1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 #include <linux/kcov.h>
35 
36 #include <linux/phy/phy.h>
37 #include <linux/usb.h>
38 #include <linux/usb/hcd.h>
39 #include <linux/usb/otg.h>
40 
41 #include "usb.h"
42 #include "phy.h"
43 
44 
45 /*-------------------------------------------------------------------------*/
46 
47 /*
48  * USB Host Controller Driver framework
49  *
50  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
51  * HCD-specific behaviors/bugs.
52  *
53  * This does error checks, tracks devices and urbs, and delegates to a
54  * "hc_driver" only for code (and data) that really needs to know about
55  * hardware differences.  That includes root hub registers, i/o queues,
56  * and so on ... but as little else as possible.
57  *
58  * Shared code includes most of the "root hub" code (these are emulated,
59  * though each HC's hardware works differently) and PCI glue, plus request
60  * tracking overhead.  The HCD code should only block on spinlocks or on
61  * hardware handshaking; blocking on software events (such as other kernel
62  * threads releasing resources, or completing actions) is all generic.
63  *
64  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
65  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
66  * only by the hub driver ... and that neither should be seen or used by
67  * usb client device drivers.
68  *
69  * Contributors of ideas or unattributed patches include: David Brownell,
70  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
71  *
72  * HISTORY:
73  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
74  *		associated cleanup.  "usb_hcd" still != "usb_bus".
75  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
76  */
77 
78 /*-------------------------------------------------------------------------*/
79 
80 /* Keep track of which host controller drivers are loaded */
81 unsigned long usb_hcds_loaded;
82 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
83 
84 /* host controllers we manage */
85 DEFINE_IDR (usb_bus_idr);
86 EXPORT_SYMBOL_GPL (usb_bus_idr);
87 
88 /* used when allocating bus numbers */
89 #define USB_MAXBUS		64
90 
91 /* used when updating list of hcds */
92 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
93 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
94 
95 /* used for controlling access to virtual root hubs */
96 static DEFINE_SPINLOCK(hcd_root_hub_lock);
97 
98 /* used when updating an endpoint's URB list */
99 static DEFINE_SPINLOCK(hcd_urb_list_lock);
100 
101 /* used to protect against unlinking URBs after the device is gone */
102 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
103 
104 /* wait queue for synchronous unlinks */
105 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
106 
107 /*-------------------------------------------------------------------------*/
108 
109 /*
110  * Sharable chunks of root hub code.
111  */
112 
113 /*-------------------------------------------------------------------------*/
114 #define KERNEL_REL	bin2bcd(LINUX_VERSION_MAJOR)
115 #define KERNEL_VER	bin2bcd(LINUX_VERSION_PATCHLEVEL)
116 
117 /* usb 3.1 root hub device descriptor */
118 static const u8 usb31_rh_dev_descriptor[18] = {
119 	0x12,       /*  __u8  bLength; */
120 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
121 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
122 
123 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
124 	0x00,	    /*  __u8  bDeviceSubClass; */
125 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
126 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
127 
128 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
129 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
130 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
131 
132 	0x03,       /*  __u8  iManufacturer; */
133 	0x02,       /*  __u8  iProduct; */
134 	0x01,       /*  __u8  iSerialNumber; */
135 	0x01        /*  __u8  bNumConfigurations; */
136 };
137 
138 /* usb 3.0 root hub device descriptor */
139 static const u8 usb3_rh_dev_descriptor[18] = {
140 	0x12,       /*  __u8  bLength; */
141 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
142 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
143 
144 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
145 	0x00,	    /*  __u8  bDeviceSubClass; */
146 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
147 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
148 
149 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
150 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
151 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
152 
153 	0x03,       /*  __u8  iManufacturer; */
154 	0x02,       /*  __u8  iProduct; */
155 	0x01,       /*  __u8  iSerialNumber; */
156 	0x01        /*  __u8  bNumConfigurations; */
157 };
158 
159 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
160 static const u8 usb25_rh_dev_descriptor[18] = {
161 	0x12,       /*  __u8  bLength; */
162 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
163 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
164 
165 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
166 	0x00,	    /*  __u8  bDeviceSubClass; */
167 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
168 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
169 
170 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
171 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
172 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
173 
174 	0x03,       /*  __u8  iManufacturer; */
175 	0x02,       /*  __u8  iProduct; */
176 	0x01,       /*  __u8  iSerialNumber; */
177 	0x01        /*  __u8  bNumConfigurations; */
178 };
179 
180 /* usb 2.0 root hub device descriptor */
181 static const u8 usb2_rh_dev_descriptor[18] = {
182 	0x12,       /*  __u8  bLength; */
183 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
184 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
185 
186 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
187 	0x00,	    /*  __u8  bDeviceSubClass; */
188 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
189 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
190 
191 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
192 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
193 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
194 
195 	0x03,       /*  __u8  iManufacturer; */
196 	0x02,       /*  __u8  iProduct; */
197 	0x01,       /*  __u8  iSerialNumber; */
198 	0x01        /*  __u8  bNumConfigurations; */
199 };
200 
201 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
202 
203 /* usb 1.1 root hub device descriptor */
204 static const u8 usb11_rh_dev_descriptor[18] = {
205 	0x12,       /*  __u8  bLength; */
206 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
207 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
208 
209 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
210 	0x00,	    /*  __u8  bDeviceSubClass; */
211 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
212 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
213 
214 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
215 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
216 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
217 
218 	0x03,       /*  __u8  iManufacturer; */
219 	0x02,       /*  __u8  iProduct; */
220 	0x01,       /*  __u8  iSerialNumber; */
221 	0x01        /*  __u8  bNumConfigurations; */
222 };
223 
224 
225 /*-------------------------------------------------------------------------*/
226 
227 /* Configuration descriptors for our root hubs */
228 
229 static const u8 fs_rh_config_descriptor[] = {
230 
231 	/* one configuration */
232 	0x09,       /*  __u8  bLength; */
233 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
234 	0x19, 0x00, /*  __le16 wTotalLength; */
235 	0x01,       /*  __u8  bNumInterfaces; (1) */
236 	0x01,       /*  __u8  bConfigurationValue; */
237 	0x00,       /*  __u8  iConfiguration; */
238 	0xc0,       /*  __u8  bmAttributes;
239 				 Bit 7: must be set,
240 				     6: Self-powered,
241 				     5: Remote wakeup,
242 				     4..0: resvd */
243 	0x00,       /*  __u8  MaxPower; */
244 
245 	/* USB 1.1:
246 	 * USB 2.0, single TT organization (mandatory):
247 	 *	one interface, protocol 0
248 	 *
249 	 * USB 2.0, multiple TT organization (optional):
250 	 *	two interfaces, protocols 1 (like single TT)
251 	 *	and 2 (multiple TT mode) ... config is
252 	 *	sometimes settable
253 	 *	NOT IMPLEMENTED
254 	 */
255 
256 	/* one interface */
257 	0x09,       /*  __u8  if_bLength; */
258 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
259 	0x00,       /*  __u8  if_bInterfaceNumber; */
260 	0x00,       /*  __u8  if_bAlternateSetting; */
261 	0x01,       /*  __u8  if_bNumEndpoints; */
262 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
263 	0x00,       /*  __u8  if_bInterfaceSubClass; */
264 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
265 	0x00,       /*  __u8  if_iInterface; */
266 
267 	/* one endpoint (status change endpoint) */
268 	0x07,       /*  __u8  ep_bLength; */
269 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
270 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
271 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
272 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
273 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
274 };
275 
276 static const u8 hs_rh_config_descriptor[] = {
277 
278 	/* one configuration */
279 	0x09,       /*  __u8  bLength; */
280 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
281 	0x19, 0x00, /*  __le16 wTotalLength; */
282 	0x01,       /*  __u8  bNumInterfaces; (1) */
283 	0x01,       /*  __u8  bConfigurationValue; */
284 	0x00,       /*  __u8  iConfiguration; */
285 	0xc0,       /*  __u8  bmAttributes;
286 				 Bit 7: must be set,
287 				     6: Self-powered,
288 				     5: Remote wakeup,
289 				     4..0: resvd */
290 	0x00,       /*  __u8  MaxPower; */
291 
292 	/* USB 1.1:
293 	 * USB 2.0, single TT organization (mandatory):
294 	 *	one interface, protocol 0
295 	 *
296 	 * USB 2.0, multiple TT organization (optional):
297 	 *	two interfaces, protocols 1 (like single TT)
298 	 *	and 2 (multiple TT mode) ... config is
299 	 *	sometimes settable
300 	 *	NOT IMPLEMENTED
301 	 */
302 
303 	/* one interface */
304 	0x09,       /*  __u8  if_bLength; */
305 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
306 	0x00,       /*  __u8  if_bInterfaceNumber; */
307 	0x00,       /*  __u8  if_bAlternateSetting; */
308 	0x01,       /*  __u8  if_bNumEndpoints; */
309 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
310 	0x00,       /*  __u8  if_bInterfaceSubClass; */
311 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
312 	0x00,       /*  __u8  if_iInterface; */
313 
314 	/* one endpoint (status change endpoint) */
315 	0x07,       /*  __u8  ep_bLength; */
316 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
317 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
318 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
319 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
320 		     * see hub.c:hub_configure() for details. */
321 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
322 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
323 };
324 
325 static const u8 ss_rh_config_descriptor[] = {
326 	/* one configuration */
327 	0x09,       /*  __u8  bLength; */
328 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
329 	0x1f, 0x00, /*  __le16 wTotalLength; */
330 	0x01,       /*  __u8  bNumInterfaces; (1) */
331 	0x01,       /*  __u8  bConfigurationValue; */
332 	0x00,       /*  __u8  iConfiguration; */
333 	0xc0,       /*  __u8  bmAttributes;
334 				 Bit 7: must be set,
335 				     6: Self-powered,
336 				     5: Remote wakeup,
337 				     4..0: resvd */
338 	0x00,       /*  __u8  MaxPower; */
339 
340 	/* one interface */
341 	0x09,       /*  __u8  if_bLength; */
342 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
343 	0x00,       /*  __u8  if_bInterfaceNumber; */
344 	0x00,       /*  __u8  if_bAlternateSetting; */
345 	0x01,       /*  __u8  if_bNumEndpoints; */
346 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
347 	0x00,       /*  __u8  if_bInterfaceSubClass; */
348 	0x00,       /*  __u8  if_bInterfaceProtocol; */
349 	0x00,       /*  __u8  if_iInterface; */
350 
351 	/* one endpoint (status change endpoint) */
352 	0x07,       /*  __u8  ep_bLength; */
353 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
354 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
355 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
356 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
357 		     * see hub.c:hub_configure() for details. */
358 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
359 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
360 
361 	/* one SuperSpeed endpoint companion descriptor */
362 	0x06,        /* __u8 ss_bLength */
363 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
364 		     /* Companion */
365 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
366 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
367 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
368 };
369 
370 /* authorized_default behaviour:
371  * -1 is authorized for all devices except wireless (old behaviour)
372  * 0 is unauthorized for all devices
373  * 1 is authorized for all devices
374  * 2 is authorized for internal devices
375  */
376 #define USB_AUTHORIZE_WIRED	-1
377 #define USB_AUTHORIZE_NONE	0
378 #define USB_AUTHORIZE_ALL	1
379 #define USB_AUTHORIZE_INTERNAL	2
380 
381 static int authorized_default = USB_AUTHORIZE_WIRED;
382 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
383 MODULE_PARM_DESC(authorized_default,
384 		"Default USB device authorization: 0 is not authorized, 1 is "
385 		"authorized, 2 is authorized for internal devices, -1 is "
386 		"authorized except for wireless USB (default, old behaviour)");
387 /*-------------------------------------------------------------------------*/
388 
389 /**
390  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
391  * @s: Null-terminated ASCII (actually ISO-8859-1) string
392  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
393  * @len: Length (in bytes; may be odd) of descriptor buffer.
394  *
395  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
396  * whichever is less.
397  *
398  * Note:
399  * USB String descriptors can contain at most 126 characters; input
400  * strings longer than that are truncated.
401  */
402 static unsigned
ascii2desc(char const * s,u8 * buf,unsigned len)403 ascii2desc(char const *s, u8 *buf, unsigned len)
404 {
405 	unsigned n, t = 2 + 2*strlen(s);
406 
407 	if (t > 254)
408 		t = 254;	/* Longest possible UTF string descriptor */
409 	if (len > t)
410 		len = t;
411 
412 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
413 
414 	n = len;
415 	while (n--) {
416 		*buf++ = t;
417 		if (!n--)
418 			break;
419 		*buf++ = t >> 8;
420 		t = (unsigned char)*s++;
421 	}
422 	return len;
423 }
424 
425 /**
426  * rh_string() - provides string descriptors for root hub
427  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
428  * @hcd: the host controller for this root hub
429  * @data: buffer for output packet
430  * @len: length of the provided buffer
431  *
432  * Produces either a manufacturer, product or serial number string for the
433  * virtual root hub device.
434  *
435  * Return: The number of bytes filled in: the length of the descriptor or
436  * of the provided buffer, whichever is less.
437  */
438 static unsigned
rh_string(int id,struct usb_hcd const * hcd,u8 * data,unsigned len)439 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
440 {
441 	char buf[100];
442 	char const *s;
443 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
444 
445 	/* language ids */
446 	switch (id) {
447 	case 0:
448 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
449 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
450 		if (len > 4)
451 			len = 4;
452 		memcpy(data, langids, len);
453 		return len;
454 	case 1:
455 		/* Serial number */
456 		s = hcd->self.bus_name;
457 		break;
458 	case 2:
459 		/* Product name */
460 		s = hcd->product_desc;
461 		break;
462 	case 3:
463 		/* Manufacturer */
464 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
465 			init_utsname()->release, hcd->driver->description);
466 		s = buf;
467 		break;
468 	default:
469 		/* Can't happen; caller guarantees it */
470 		return 0;
471 	}
472 
473 	return ascii2desc(s, data, len);
474 }
475 
476 
477 /* Root hub control transfers execute synchronously */
rh_call_control(struct usb_hcd * hcd,struct urb * urb)478 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
479 {
480 	struct usb_ctrlrequest *cmd;
481 	u16		typeReq, wValue, wIndex, wLength;
482 	u8		*ubuf = urb->transfer_buffer;
483 	unsigned	len = 0;
484 	int		status;
485 	u8		patch_wakeup = 0;
486 	u8		patch_protocol = 0;
487 	u16		tbuf_size;
488 	u8		*tbuf = NULL;
489 	const u8	*bufp;
490 
491 	might_sleep();
492 
493 	spin_lock_irq(&hcd_root_hub_lock);
494 	status = usb_hcd_link_urb_to_ep(hcd, urb);
495 	spin_unlock_irq(&hcd_root_hub_lock);
496 	if (status)
497 		return status;
498 	urb->hcpriv = hcd;	/* Indicate it's queued */
499 
500 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
501 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
502 	wValue   = le16_to_cpu (cmd->wValue);
503 	wIndex   = le16_to_cpu (cmd->wIndex);
504 	wLength  = le16_to_cpu (cmd->wLength);
505 
506 	if (wLength > urb->transfer_buffer_length)
507 		goto error;
508 
509 	/*
510 	 * tbuf should be at least as big as the
511 	 * USB hub descriptor.
512 	 */
513 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
514 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
515 	if (!tbuf) {
516 		status = -ENOMEM;
517 		goto err_alloc;
518 	}
519 
520 	bufp = tbuf;
521 
522 
523 	urb->actual_length = 0;
524 	switch (typeReq) {
525 
526 	/* DEVICE REQUESTS */
527 
528 	/* The root hub's remote wakeup enable bit is implemented using
529 	 * driver model wakeup flags.  If this system supports wakeup
530 	 * through USB, userspace may change the default "allow wakeup"
531 	 * policy through sysfs or these calls.
532 	 *
533 	 * Most root hubs support wakeup from downstream devices, for
534 	 * runtime power management (disabling USB clocks and reducing
535 	 * VBUS power usage).  However, not all of them do so; silicon,
536 	 * board, and BIOS bugs here are not uncommon, so these can't
537 	 * be treated quite like external hubs.
538 	 *
539 	 * Likewise, not all root hubs will pass wakeup events upstream,
540 	 * to wake up the whole system.  So don't assume root hub and
541 	 * controller capabilities are identical.
542 	 */
543 
544 	case DeviceRequest | USB_REQ_GET_STATUS:
545 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
546 					<< USB_DEVICE_REMOTE_WAKEUP)
547 				| (1 << USB_DEVICE_SELF_POWERED);
548 		tbuf[1] = 0;
549 		len = 2;
550 		break;
551 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
552 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
553 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
554 		else
555 			goto error;
556 		break;
557 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
558 		if (device_can_wakeup(&hcd->self.root_hub->dev)
559 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
560 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
561 		else
562 			goto error;
563 		break;
564 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
565 		tbuf[0] = 1;
566 		len = 1;
567 		fallthrough;
568 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
569 		break;
570 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
571 		switch (wValue & 0xff00) {
572 		case USB_DT_DEVICE << 8:
573 			switch (hcd->speed) {
574 			case HCD_USB32:
575 			case HCD_USB31:
576 				bufp = usb31_rh_dev_descriptor;
577 				break;
578 			case HCD_USB3:
579 				bufp = usb3_rh_dev_descriptor;
580 				break;
581 			case HCD_USB25:
582 				bufp = usb25_rh_dev_descriptor;
583 				break;
584 			case HCD_USB2:
585 				bufp = usb2_rh_dev_descriptor;
586 				break;
587 			case HCD_USB11:
588 				bufp = usb11_rh_dev_descriptor;
589 				break;
590 			default:
591 				goto error;
592 			}
593 			len = 18;
594 			if (hcd->has_tt)
595 				patch_protocol = 1;
596 			break;
597 		case USB_DT_CONFIG << 8:
598 			switch (hcd->speed) {
599 			case HCD_USB32:
600 			case HCD_USB31:
601 			case HCD_USB3:
602 				bufp = ss_rh_config_descriptor;
603 				len = sizeof ss_rh_config_descriptor;
604 				break;
605 			case HCD_USB25:
606 			case HCD_USB2:
607 				bufp = hs_rh_config_descriptor;
608 				len = sizeof hs_rh_config_descriptor;
609 				break;
610 			case HCD_USB11:
611 				bufp = fs_rh_config_descriptor;
612 				len = sizeof fs_rh_config_descriptor;
613 				break;
614 			default:
615 				goto error;
616 			}
617 			if (device_can_wakeup(&hcd->self.root_hub->dev))
618 				patch_wakeup = 1;
619 			break;
620 		case USB_DT_STRING << 8:
621 			if ((wValue & 0xff) < 4)
622 				urb->actual_length = rh_string(wValue & 0xff,
623 						hcd, ubuf, wLength);
624 			else /* unsupported IDs --> "protocol stall" */
625 				goto error;
626 			break;
627 		case USB_DT_BOS << 8:
628 			goto nongeneric;
629 		default:
630 			goto error;
631 		}
632 		break;
633 	case DeviceRequest | USB_REQ_GET_INTERFACE:
634 		tbuf[0] = 0;
635 		len = 1;
636 		fallthrough;
637 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
638 		break;
639 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
640 		/* wValue == urb->dev->devaddr */
641 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
642 			wValue);
643 		break;
644 
645 	/* INTERFACE REQUESTS (no defined feature/status flags) */
646 
647 	/* ENDPOINT REQUESTS */
648 
649 	case EndpointRequest | USB_REQ_GET_STATUS:
650 		/* ENDPOINT_HALT flag */
651 		tbuf[0] = 0;
652 		tbuf[1] = 0;
653 		len = 2;
654 		fallthrough;
655 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
656 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
657 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
658 		break;
659 
660 	/* CLASS REQUESTS (and errors) */
661 
662 	default:
663 nongeneric:
664 		/* non-generic request */
665 		switch (typeReq) {
666 		case GetHubStatus:
667 			len = 4;
668 			break;
669 		case GetPortStatus:
670 			if (wValue == HUB_PORT_STATUS)
671 				len = 4;
672 			else
673 				/* other port status types return 8 bytes */
674 				len = 8;
675 			break;
676 		case GetHubDescriptor:
677 			len = sizeof (struct usb_hub_descriptor);
678 			break;
679 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
680 			/* len is returned by hub_control */
681 			break;
682 		}
683 		status = hcd->driver->hub_control (hcd,
684 			typeReq, wValue, wIndex,
685 			tbuf, wLength);
686 
687 		if (typeReq == GetHubDescriptor)
688 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
689 				(struct usb_hub_descriptor *)tbuf);
690 		break;
691 error:
692 		/* "protocol stall" on error */
693 		status = -EPIPE;
694 	}
695 
696 	if (status < 0) {
697 		len = 0;
698 		if (status != -EPIPE) {
699 			dev_dbg (hcd->self.controller,
700 				"CTRL: TypeReq=0x%x val=0x%x "
701 				"idx=0x%x len=%d ==> %d\n",
702 				typeReq, wValue, wIndex,
703 				wLength, status);
704 		}
705 	} else if (status > 0) {
706 		/* hub_control may return the length of data copied. */
707 		len = status;
708 		status = 0;
709 	}
710 	if (len) {
711 		if (urb->transfer_buffer_length < len)
712 			len = urb->transfer_buffer_length;
713 		urb->actual_length = len;
714 		/* always USB_DIR_IN, toward host */
715 		memcpy (ubuf, bufp, len);
716 
717 		/* report whether RH hardware supports remote wakeup */
718 		if (patch_wakeup &&
719 				len > offsetof (struct usb_config_descriptor,
720 						bmAttributes))
721 			((struct usb_config_descriptor *)ubuf)->bmAttributes
722 				|= USB_CONFIG_ATT_WAKEUP;
723 
724 		/* report whether RH hardware has an integrated TT */
725 		if (patch_protocol &&
726 				len > offsetof(struct usb_device_descriptor,
727 						bDeviceProtocol))
728 			((struct usb_device_descriptor *) ubuf)->
729 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
730 	}
731 
732 	kfree(tbuf);
733  err_alloc:
734 
735 	/* any errors get returned through the urb completion */
736 	spin_lock_irq(&hcd_root_hub_lock);
737 	usb_hcd_unlink_urb_from_ep(hcd, urb);
738 	usb_hcd_giveback_urb(hcd, urb, status);
739 	spin_unlock_irq(&hcd_root_hub_lock);
740 	return 0;
741 }
742 
743 /*-------------------------------------------------------------------------*/
744 
745 /*
746  * Root Hub interrupt transfers are polled using a timer if the
747  * driver requests it; otherwise the driver is responsible for
748  * calling usb_hcd_poll_rh_status() when an event occurs.
749  *
750  * Completion handler may not sleep. See usb_hcd_giveback_urb() for details.
751  */
usb_hcd_poll_rh_status(struct usb_hcd * hcd)752 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
753 {
754 	struct urb	*urb;
755 	int		length;
756 	unsigned long	flags;
757 	char		buffer[6];	/* Any root hubs with > 31 ports? */
758 
759 	if (unlikely(!hcd->rh_pollable))
760 		return;
761 	if (!hcd->uses_new_polling && !hcd->status_urb)
762 		return;
763 
764 	length = hcd->driver->hub_status_data(hcd, buffer);
765 	if (length > 0) {
766 
767 		/* try to complete the status urb */
768 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
769 		urb = hcd->status_urb;
770 		if (urb) {
771 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
772 			hcd->status_urb = NULL;
773 			urb->actual_length = length;
774 			memcpy(urb->transfer_buffer, buffer, length);
775 
776 			usb_hcd_unlink_urb_from_ep(hcd, urb);
777 			usb_hcd_giveback_urb(hcd, urb, 0);
778 		} else {
779 			length = 0;
780 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
781 		}
782 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
783 	}
784 
785 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
786 	 * exceed that limit if HZ is 100. The math is more clunky than
787 	 * maybe expected, this is to make sure that all timers for USB devices
788 	 * fire at the same time to give the CPU a break in between */
789 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
790 			(length == 0 && hcd->status_urb != NULL))
791 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
792 }
793 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
794 
795 /* timer callback */
rh_timer_func(struct timer_list * t)796 static void rh_timer_func (struct timer_list *t)
797 {
798 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
799 
800 	usb_hcd_poll_rh_status(_hcd);
801 }
802 
803 /*-------------------------------------------------------------------------*/
804 
rh_queue_status(struct usb_hcd * hcd,struct urb * urb)805 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
806 {
807 	int		retval;
808 	unsigned long	flags;
809 	unsigned	len = 1 + (urb->dev->maxchild / 8);
810 
811 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
812 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
813 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
814 		retval = -EINVAL;
815 		goto done;
816 	}
817 
818 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
819 	if (retval)
820 		goto done;
821 
822 	hcd->status_urb = urb;
823 	urb->hcpriv = hcd;	/* indicate it's queued */
824 	if (!hcd->uses_new_polling)
825 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
826 
827 	/* If a status change has already occurred, report it ASAP */
828 	else if (HCD_POLL_PENDING(hcd))
829 		mod_timer(&hcd->rh_timer, jiffies);
830 	retval = 0;
831  done:
832 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
833 	return retval;
834 }
835 
rh_urb_enqueue(struct usb_hcd * hcd,struct urb * urb)836 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
837 {
838 	if (usb_endpoint_xfer_int(&urb->ep->desc))
839 		return rh_queue_status (hcd, urb);
840 	if (usb_endpoint_xfer_control(&urb->ep->desc))
841 		return rh_call_control (hcd, urb);
842 	return -EINVAL;
843 }
844 
845 /*-------------------------------------------------------------------------*/
846 
847 /* Unlinks of root-hub control URBs are legal, but they don't do anything
848  * since these URBs always execute synchronously.
849  */
usb_rh_urb_dequeue(struct usb_hcd * hcd,struct urb * urb,int status)850 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
851 {
852 	unsigned long	flags;
853 	int		rc;
854 
855 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
856 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
857 	if (rc)
858 		goto done;
859 
860 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
861 		;	/* Do nothing */
862 
863 	} else {				/* Status URB */
864 		if (!hcd->uses_new_polling)
865 			del_timer (&hcd->rh_timer);
866 		if (urb == hcd->status_urb) {
867 			hcd->status_urb = NULL;
868 			usb_hcd_unlink_urb_from_ep(hcd, urb);
869 			usb_hcd_giveback_urb(hcd, urb, status);
870 		}
871 	}
872  done:
873 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
874 	return rc;
875 }
876 
877 
878 /*-------------------------------------------------------------------------*/
879 
880 /**
881  * usb_bus_init - shared initialization code
882  * @bus: the bus structure being initialized
883  *
884  * This code is used to initialize a usb_bus structure, memory for which is
885  * separately managed.
886  */
usb_bus_init(struct usb_bus * bus)887 static void usb_bus_init (struct usb_bus *bus)
888 {
889 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
890 
891 	bus->devnum_next = 1;
892 
893 	bus->root_hub = NULL;
894 	bus->busnum = -1;
895 	bus->bandwidth_allocated = 0;
896 	bus->bandwidth_int_reqs  = 0;
897 	bus->bandwidth_isoc_reqs = 0;
898 	mutex_init(&bus->devnum_next_mutex);
899 }
900 
901 /*-------------------------------------------------------------------------*/
902 
903 /**
904  * usb_register_bus - registers the USB host controller with the usb core
905  * @bus: pointer to the bus to register
906  *
907  * Context: task context, might sleep.
908  *
909  * Assigns a bus number, and links the controller into usbcore data
910  * structures so that it can be seen by scanning the bus list.
911  *
912  * Return: 0 if successful. A negative error code otherwise.
913  */
usb_register_bus(struct usb_bus * bus)914 static int usb_register_bus(struct usb_bus *bus)
915 {
916 	int result = -E2BIG;
917 	int busnum;
918 
919 	mutex_lock(&usb_bus_idr_lock);
920 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
921 	if (busnum < 0) {
922 		pr_err("%s: failed to get bus number\n", usbcore_name);
923 		goto error_find_busnum;
924 	}
925 	bus->busnum = busnum;
926 	mutex_unlock(&usb_bus_idr_lock);
927 
928 	usb_notify_add_bus(bus);
929 
930 	dev_info (bus->controller, "new USB bus registered, assigned bus "
931 		  "number %d\n", bus->busnum);
932 	return 0;
933 
934 error_find_busnum:
935 	mutex_unlock(&usb_bus_idr_lock);
936 	return result;
937 }
938 
939 /**
940  * usb_deregister_bus - deregisters the USB host controller
941  * @bus: pointer to the bus to deregister
942  *
943  * Context: task context, might sleep.
944  *
945  * Recycles the bus number, and unlinks the controller from usbcore data
946  * structures so that it won't be seen by scanning the bus list.
947  */
usb_deregister_bus(struct usb_bus * bus)948 static void usb_deregister_bus (struct usb_bus *bus)
949 {
950 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
951 
952 	/*
953 	 * NOTE: make sure that all the devices are removed by the
954 	 * controller code, as well as having it call this when cleaning
955 	 * itself up
956 	 */
957 	mutex_lock(&usb_bus_idr_lock);
958 	idr_remove(&usb_bus_idr, bus->busnum);
959 	mutex_unlock(&usb_bus_idr_lock);
960 
961 	usb_notify_remove_bus(bus);
962 }
963 
964 /**
965  * register_root_hub - called by usb_add_hcd() to register a root hub
966  * @hcd: host controller for this root hub
967  *
968  * This function registers the root hub with the USB subsystem.  It sets up
969  * the device properly in the device tree and then calls usb_new_device()
970  * to register the usb device.  It also assigns the root hub's USB address
971  * (always 1).
972  *
973  * Return: 0 if successful. A negative error code otherwise.
974  */
register_root_hub(struct usb_hcd * hcd)975 static int register_root_hub(struct usb_hcd *hcd)
976 {
977 	struct device *parent_dev = hcd->self.controller;
978 	struct usb_device *usb_dev = hcd->self.root_hub;
979 	const int devnum = 1;
980 	int retval;
981 
982 	usb_dev->devnum = devnum;
983 	usb_dev->bus->devnum_next = devnum + 1;
984 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
985 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
986 
987 	mutex_lock(&usb_bus_idr_lock);
988 
989 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
990 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
991 	if (retval != sizeof usb_dev->descriptor) {
992 		mutex_unlock(&usb_bus_idr_lock);
993 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
994 				dev_name(&usb_dev->dev), retval);
995 		return (retval < 0) ? retval : -EMSGSIZE;
996 	}
997 
998 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
999 		retval = usb_get_bos_descriptor(usb_dev);
1000 		if (!retval) {
1001 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1002 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1003 			mutex_unlock(&usb_bus_idr_lock);
1004 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1005 					dev_name(&usb_dev->dev), retval);
1006 			return retval;
1007 		}
1008 	}
1009 
1010 	retval = usb_new_device (usb_dev);
1011 	if (retval) {
1012 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1013 				dev_name(&usb_dev->dev), retval);
1014 	} else {
1015 		spin_lock_irq (&hcd_root_hub_lock);
1016 		hcd->rh_registered = 1;
1017 		spin_unlock_irq (&hcd_root_hub_lock);
1018 
1019 		/* Did the HC die before the root hub was registered? */
1020 		if (HCD_DEAD(hcd))
1021 			usb_hc_died (hcd);	/* This time clean up */
1022 	}
1023 	mutex_unlock(&usb_bus_idr_lock);
1024 
1025 	return retval;
1026 }
1027 
1028 /*
1029  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1030  * @bus: the bus which the root hub belongs to
1031  * @portnum: the port which is being resumed
1032  *
1033  * HCDs should call this function when they know that a resume signal is
1034  * being sent to a root-hub port.  The root hub will be prevented from
1035  * going into autosuspend until usb_hcd_end_port_resume() is called.
1036  *
1037  * The bus's private lock must be held by the caller.
1038  */
usb_hcd_start_port_resume(struct usb_bus * bus,int portnum)1039 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1040 {
1041 	unsigned bit = 1 << portnum;
1042 
1043 	if (!(bus->resuming_ports & bit)) {
1044 		bus->resuming_ports |= bit;
1045 		pm_runtime_get_noresume(&bus->root_hub->dev);
1046 	}
1047 }
1048 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1049 
1050 /*
1051  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1052  * @bus: the bus which the root hub belongs to
1053  * @portnum: the port which is being resumed
1054  *
1055  * HCDs should call this function when they know that a resume signal has
1056  * stopped being sent to a root-hub port.  The root hub will be allowed to
1057  * autosuspend again.
1058  *
1059  * The bus's private lock must be held by the caller.
1060  */
usb_hcd_end_port_resume(struct usb_bus * bus,int portnum)1061 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1062 {
1063 	unsigned bit = 1 << portnum;
1064 
1065 	if (bus->resuming_ports & bit) {
1066 		bus->resuming_ports &= ~bit;
1067 		pm_runtime_put_noidle(&bus->root_hub->dev);
1068 	}
1069 }
1070 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1071 
1072 /*-------------------------------------------------------------------------*/
1073 
1074 /**
1075  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1076  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1077  * @is_input: true iff the transaction sends data to the host
1078  * @isoc: true for isochronous transactions, false for interrupt ones
1079  * @bytecount: how many bytes in the transaction.
1080  *
1081  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1082  *
1083  * Note:
1084  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1085  * scheduled in software, this function is only used for such scheduling.
1086  */
usb_calc_bus_time(int speed,int is_input,int isoc,int bytecount)1087 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1088 {
1089 	unsigned long	tmp;
1090 
1091 	switch (speed) {
1092 	case USB_SPEED_LOW: 	/* INTR only */
1093 		if (is_input) {
1094 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1095 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1096 		} else {
1097 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1098 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1099 		}
1100 	case USB_SPEED_FULL:	/* ISOC or INTR */
1101 		if (isoc) {
1102 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1103 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1104 		} else {
1105 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1106 			return 9107L + BW_HOST_DELAY + tmp;
1107 		}
1108 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1109 		/* FIXME adjust for input vs output */
1110 		if (isoc)
1111 			tmp = HS_NSECS_ISO (bytecount);
1112 		else
1113 			tmp = HS_NSECS (bytecount);
1114 		return tmp;
1115 	default:
1116 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1117 		return -1;
1118 	}
1119 }
1120 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1121 
1122 
1123 /*-------------------------------------------------------------------------*/
1124 
1125 /*
1126  * Generic HC operations.
1127  */
1128 
1129 /*-------------------------------------------------------------------------*/
1130 
1131 /**
1132  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1133  * @hcd: host controller to which @urb was submitted
1134  * @urb: URB being submitted
1135  *
1136  * Host controller drivers should call this routine in their enqueue()
1137  * method.  The HCD's private spinlock must be held and interrupts must
1138  * be disabled.  The actions carried out here are required for URB
1139  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1140  *
1141  * Return: 0 for no error, otherwise a negative error code (in which case
1142  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1143  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1144  * the private spinlock and returning.
1145  */
usb_hcd_link_urb_to_ep(struct usb_hcd * hcd,struct urb * urb)1146 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1147 {
1148 	int		rc = 0;
1149 
1150 	spin_lock(&hcd_urb_list_lock);
1151 
1152 	/* Check that the URB isn't being killed */
1153 	if (unlikely(atomic_read(&urb->reject))) {
1154 		rc = -EPERM;
1155 		goto done;
1156 	}
1157 
1158 	if (unlikely(!urb->ep->enabled)) {
1159 		rc = -ENOENT;
1160 		goto done;
1161 	}
1162 
1163 	if (unlikely(!urb->dev->can_submit)) {
1164 		rc = -EHOSTUNREACH;
1165 		goto done;
1166 	}
1167 
1168 	/*
1169 	 * Check the host controller's state and add the URB to the
1170 	 * endpoint's queue.
1171 	 */
1172 	if (HCD_RH_RUNNING(hcd)) {
1173 		urb->unlinked = 0;
1174 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1175 	} else {
1176 		rc = -ESHUTDOWN;
1177 		goto done;
1178 	}
1179  done:
1180 	spin_unlock(&hcd_urb_list_lock);
1181 	return rc;
1182 }
1183 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1184 
1185 /**
1186  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1187  * @hcd: host controller to which @urb was submitted
1188  * @urb: URB being checked for unlinkability
1189  * @status: error code to store in @urb if the unlink succeeds
1190  *
1191  * Host controller drivers should call this routine in their dequeue()
1192  * method.  The HCD's private spinlock must be held and interrupts must
1193  * be disabled.  The actions carried out here are required for making
1194  * sure than an unlink is valid.
1195  *
1196  * Return: 0 for no error, otherwise a negative error code (in which case
1197  * the dequeue() method must fail).  The possible error codes are:
1198  *
1199  *	-EIDRM: @urb was not submitted or has already completed.
1200  *		The completion function may not have been called yet.
1201  *
1202  *	-EBUSY: @urb has already been unlinked.
1203  */
usb_hcd_check_unlink_urb(struct usb_hcd * hcd,struct urb * urb,int status)1204 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1205 		int status)
1206 {
1207 	struct list_head	*tmp;
1208 
1209 	/* insist the urb is still queued */
1210 	list_for_each(tmp, &urb->ep->urb_list) {
1211 		if (tmp == &urb->urb_list)
1212 			break;
1213 	}
1214 	if (tmp != &urb->urb_list)
1215 		return -EIDRM;
1216 
1217 	/* Any status except -EINPROGRESS means something already started to
1218 	 * unlink this URB from the hardware.  So there's no more work to do.
1219 	 */
1220 	if (urb->unlinked)
1221 		return -EBUSY;
1222 	urb->unlinked = status;
1223 	return 0;
1224 }
1225 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1226 
1227 /**
1228  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1229  * @hcd: host controller to which @urb was submitted
1230  * @urb: URB being unlinked
1231  *
1232  * Host controller drivers should call this routine before calling
1233  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1234  * interrupts must be disabled.  The actions carried out here are required
1235  * for URB completion.
1236  */
usb_hcd_unlink_urb_from_ep(struct usb_hcd * hcd,struct urb * urb)1237 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1238 {
1239 	/* clear all state linking urb to this dev (and hcd) */
1240 	spin_lock(&hcd_urb_list_lock);
1241 	list_del_init(&urb->urb_list);
1242 	spin_unlock(&hcd_urb_list_lock);
1243 }
1244 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1245 
1246 /*
1247  * Some usb host controllers can only perform dma using a small SRAM area.
1248  * The usb core itself is however optimized for host controllers that can dma
1249  * using regular system memory - like pci devices doing bus mastering.
1250  *
1251  * To support host controllers with limited dma capabilities we provide dma
1252  * bounce buffers. This feature can be enabled by initializing
1253  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1254  *
1255  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1256  * data for dma using the genalloc API.
1257  *
1258  * So, to summarize...
1259  *
1260  * - We need "local" memory, canonical example being
1261  *   a small SRAM on a discrete controller being the
1262  *   only memory that the controller can read ...
1263  *   (a) "normal" kernel memory is no good, and
1264  *   (b) there's not enough to share
1265  *
1266  * - So we use that, even though the primary requirement
1267  *   is that the memory be "local" (hence addressable
1268  *   by that device), not "coherent".
1269  *
1270  */
1271 
hcd_alloc_coherent(struct usb_bus * bus,gfp_t mem_flags,dma_addr_t * dma_handle,void ** vaddr_handle,size_t size,enum dma_data_direction dir)1272 static int hcd_alloc_coherent(struct usb_bus *bus,
1273 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1274 			      void **vaddr_handle, size_t size,
1275 			      enum dma_data_direction dir)
1276 {
1277 	unsigned char *vaddr;
1278 
1279 	if (*vaddr_handle == NULL) {
1280 		WARN_ON_ONCE(1);
1281 		return -EFAULT;
1282 	}
1283 
1284 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1285 				 mem_flags, dma_handle);
1286 	if (!vaddr)
1287 		return -ENOMEM;
1288 
1289 	/*
1290 	 * Store the virtual address of the buffer at the end
1291 	 * of the allocated dma buffer. The size of the buffer
1292 	 * may be uneven so use unaligned functions instead
1293 	 * of just rounding up. It makes sense to optimize for
1294 	 * memory footprint over access speed since the amount
1295 	 * of memory available for dma may be limited.
1296 	 */
1297 	put_unaligned((unsigned long)*vaddr_handle,
1298 		      (unsigned long *)(vaddr + size));
1299 
1300 	if (dir == DMA_TO_DEVICE)
1301 		memcpy(vaddr, *vaddr_handle, size);
1302 
1303 	*vaddr_handle = vaddr;
1304 	return 0;
1305 }
1306 
hcd_free_coherent(struct usb_bus * bus,dma_addr_t * dma_handle,void ** vaddr_handle,size_t size,enum dma_data_direction dir)1307 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1308 			      void **vaddr_handle, size_t size,
1309 			      enum dma_data_direction dir)
1310 {
1311 	unsigned char *vaddr = *vaddr_handle;
1312 
1313 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1314 
1315 	if (dir == DMA_FROM_DEVICE)
1316 		memcpy(vaddr, *vaddr_handle, size);
1317 
1318 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1319 
1320 	*vaddr_handle = vaddr;
1321 	*dma_handle = 0;
1322 }
1323 
usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd * hcd,struct urb * urb)1324 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1325 {
1326 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1327 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1328 		dma_unmap_single(hcd->self.sysdev,
1329 				urb->setup_dma,
1330 				sizeof(struct usb_ctrlrequest),
1331 				DMA_TO_DEVICE);
1332 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1333 		hcd_free_coherent(urb->dev->bus,
1334 				&urb->setup_dma,
1335 				(void **) &urb->setup_packet,
1336 				sizeof(struct usb_ctrlrequest),
1337 				DMA_TO_DEVICE);
1338 
1339 	/* Make it safe to call this routine more than once */
1340 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1341 }
1342 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1343 
unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)1344 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1345 {
1346 	if (hcd->driver->unmap_urb_for_dma)
1347 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1348 	else
1349 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1350 }
1351 
usb_hcd_unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)1352 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1353 {
1354 	enum dma_data_direction dir;
1355 
1356 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1357 
1358 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1359 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1360 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1361 		dma_unmap_sg(hcd->self.sysdev,
1362 				urb->sg,
1363 				urb->num_sgs,
1364 				dir);
1365 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1366 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1367 		dma_unmap_page(hcd->self.sysdev,
1368 				urb->transfer_dma,
1369 				urb->transfer_buffer_length,
1370 				dir);
1371 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1372 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1373 		dma_unmap_single(hcd->self.sysdev,
1374 				urb->transfer_dma,
1375 				urb->transfer_buffer_length,
1376 				dir);
1377 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1378 		hcd_free_coherent(urb->dev->bus,
1379 				&urb->transfer_dma,
1380 				&urb->transfer_buffer,
1381 				urb->transfer_buffer_length,
1382 				dir);
1383 
1384 	/* Make it safe to call this routine more than once */
1385 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1386 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1387 }
1388 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1389 
map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)1390 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1391 			   gfp_t mem_flags)
1392 {
1393 	if (hcd->driver->map_urb_for_dma)
1394 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1395 	else
1396 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1397 }
1398 
usb_hcd_map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)1399 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1400 			    gfp_t mem_flags)
1401 {
1402 	enum dma_data_direction dir;
1403 	int ret = 0;
1404 
1405 	/* Map the URB's buffers for DMA access.
1406 	 * Lower level HCD code should use *_dma exclusively,
1407 	 * unless it uses pio or talks to another transport,
1408 	 * or uses the provided scatter gather list for bulk.
1409 	 */
1410 
1411 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1412 		if (hcd->self.uses_pio_for_control)
1413 			return ret;
1414 		if (hcd->localmem_pool) {
1415 			ret = hcd_alloc_coherent(
1416 					urb->dev->bus, mem_flags,
1417 					&urb->setup_dma,
1418 					(void **)&urb->setup_packet,
1419 					sizeof(struct usb_ctrlrequest),
1420 					DMA_TO_DEVICE);
1421 			if (ret)
1422 				return ret;
1423 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1424 		} else if (hcd_uses_dma(hcd)) {
1425 			if (object_is_on_stack(urb->setup_packet)) {
1426 				WARN_ONCE(1, "setup packet is on stack\n");
1427 				return -EAGAIN;
1428 			}
1429 
1430 			urb->setup_dma = dma_map_single(
1431 					hcd->self.sysdev,
1432 					urb->setup_packet,
1433 					sizeof(struct usb_ctrlrequest),
1434 					DMA_TO_DEVICE);
1435 			if (dma_mapping_error(hcd->self.sysdev,
1436 						urb->setup_dma))
1437 				return -EAGAIN;
1438 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1439 		}
1440 	}
1441 
1442 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1443 	if (urb->transfer_buffer_length != 0
1444 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1445 		if (hcd->localmem_pool) {
1446 			ret = hcd_alloc_coherent(
1447 					urb->dev->bus, mem_flags,
1448 					&urb->transfer_dma,
1449 					&urb->transfer_buffer,
1450 					urb->transfer_buffer_length,
1451 					dir);
1452 			if (ret == 0)
1453 				urb->transfer_flags |= URB_MAP_LOCAL;
1454 		} else if (hcd_uses_dma(hcd)) {
1455 			if (urb->num_sgs) {
1456 				int n;
1457 
1458 				/* We don't support sg for isoc transfers ! */
1459 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1460 					WARN_ON(1);
1461 					return -EINVAL;
1462 				}
1463 
1464 				n = dma_map_sg(
1465 						hcd->self.sysdev,
1466 						urb->sg,
1467 						urb->num_sgs,
1468 						dir);
1469 				if (n <= 0)
1470 					ret = -EAGAIN;
1471 				else
1472 					urb->transfer_flags |= URB_DMA_MAP_SG;
1473 				urb->num_mapped_sgs = n;
1474 				if (n != urb->num_sgs)
1475 					urb->transfer_flags |=
1476 							URB_DMA_SG_COMBINED;
1477 			} else if (urb->sg) {
1478 				struct scatterlist *sg = urb->sg;
1479 				urb->transfer_dma = dma_map_page(
1480 						hcd->self.sysdev,
1481 						sg_page(sg),
1482 						sg->offset,
1483 						urb->transfer_buffer_length,
1484 						dir);
1485 				if (dma_mapping_error(hcd->self.sysdev,
1486 						urb->transfer_dma))
1487 					ret = -EAGAIN;
1488 				else
1489 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1490 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1491 				WARN_ONCE(1, "transfer buffer is on stack\n");
1492 				ret = -EAGAIN;
1493 			} else {
1494 				urb->transfer_dma = dma_map_single(
1495 						hcd->self.sysdev,
1496 						urb->transfer_buffer,
1497 						urb->transfer_buffer_length,
1498 						dir);
1499 				if (dma_mapping_error(hcd->self.sysdev,
1500 						urb->transfer_dma))
1501 					ret = -EAGAIN;
1502 				else
1503 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1504 			}
1505 		}
1506 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1507 				URB_SETUP_MAP_LOCAL)))
1508 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1509 	}
1510 	return ret;
1511 }
1512 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1513 
1514 /*-------------------------------------------------------------------------*/
1515 
1516 /* may be called in any context with a valid urb->dev usecount
1517  * caller surrenders "ownership" of urb
1518  * expects usb_submit_urb() to have sanity checked and conditioned all
1519  * inputs in the urb
1520  */
usb_hcd_submit_urb(struct urb * urb,gfp_t mem_flags)1521 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1522 {
1523 	int			status;
1524 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1525 
1526 	/* increment urb's reference count as part of giving it to the HCD
1527 	 * (which will control it).  HCD guarantees that it either returns
1528 	 * an error or calls giveback(), but not both.
1529 	 */
1530 	usb_get_urb(urb);
1531 	atomic_inc(&urb->use_count);
1532 	atomic_inc(&urb->dev->urbnum);
1533 	usbmon_urb_submit(&hcd->self, urb);
1534 
1535 	/* NOTE requirements on root-hub callers (usbfs and the hub
1536 	 * driver, for now):  URBs' urb->transfer_buffer must be
1537 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1538 	 * they could clobber root hub response data.  Also, control
1539 	 * URBs must be submitted in process context with interrupts
1540 	 * enabled.
1541 	 */
1542 
1543 	if (is_root_hub(urb->dev)) {
1544 		status = rh_urb_enqueue(hcd, urb);
1545 	} else {
1546 		status = map_urb_for_dma(hcd, urb, mem_flags);
1547 		if (likely(status == 0)) {
1548 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1549 			if (unlikely(status))
1550 				unmap_urb_for_dma(hcd, urb);
1551 		}
1552 	}
1553 
1554 	if (unlikely(status)) {
1555 		usbmon_urb_submit_error(&hcd->self, urb, status);
1556 		urb->hcpriv = NULL;
1557 		INIT_LIST_HEAD(&urb->urb_list);
1558 		atomic_dec(&urb->use_count);
1559 		atomic_dec(&urb->dev->urbnum);
1560 		if (atomic_read(&urb->reject))
1561 			wake_up(&usb_kill_urb_queue);
1562 		usb_put_urb(urb);
1563 	}
1564 	return status;
1565 }
1566 
1567 /*-------------------------------------------------------------------------*/
1568 
1569 /* this makes the hcd giveback() the urb more quickly, by kicking it
1570  * off hardware queues (which may take a while) and returning it as
1571  * soon as practical.  we've already set up the urb's return status,
1572  * but we can't know if the callback completed already.
1573  */
unlink1(struct usb_hcd * hcd,struct urb * urb,int status)1574 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1575 {
1576 	int		value;
1577 
1578 	if (is_root_hub(urb->dev))
1579 		value = usb_rh_urb_dequeue(hcd, urb, status);
1580 	else {
1581 
1582 		/* The only reason an HCD might fail this call is if
1583 		 * it has not yet fully queued the urb to begin with.
1584 		 * Such failures should be harmless. */
1585 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1586 	}
1587 	return value;
1588 }
1589 
1590 /*
1591  * called in any context
1592  *
1593  * caller guarantees urb won't be recycled till both unlink()
1594  * and the urb's completion function return
1595  */
usb_hcd_unlink_urb(struct urb * urb,int status)1596 int usb_hcd_unlink_urb (struct urb *urb, int status)
1597 {
1598 	struct usb_hcd		*hcd;
1599 	struct usb_device	*udev = urb->dev;
1600 	int			retval = -EIDRM;
1601 	unsigned long		flags;
1602 
1603 	/* Prevent the device and bus from going away while
1604 	 * the unlink is carried out.  If they are already gone
1605 	 * then urb->use_count must be 0, since disconnected
1606 	 * devices can't have any active URBs.
1607 	 */
1608 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1609 	if (atomic_read(&urb->use_count) > 0) {
1610 		retval = 0;
1611 		usb_get_dev(udev);
1612 	}
1613 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1614 	if (retval == 0) {
1615 		hcd = bus_to_hcd(urb->dev->bus);
1616 		retval = unlink1(hcd, urb, status);
1617 		if (retval == 0)
1618 			retval = -EINPROGRESS;
1619 		else if (retval != -EIDRM && retval != -EBUSY)
1620 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1621 					urb, retval);
1622 		usb_put_dev(udev);
1623 	}
1624 	return retval;
1625 }
1626 
1627 /*-------------------------------------------------------------------------*/
1628 
__usb_hcd_giveback_urb(struct urb * urb)1629 static void __usb_hcd_giveback_urb(struct urb *urb)
1630 {
1631 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1632 	struct usb_anchor *anchor = urb->anchor;
1633 	int status = urb->unlinked;
1634 
1635 	urb->hcpriv = NULL;
1636 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1637 	    urb->actual_length < urb->transfer_buffer_length &&
1638 	    !status))
1639 		status = -EREMOTEIO;
1640 
1641 	unmap_urb_for_dma(hcd, urb);
1642 	usbmon_urb_complete(&hcd->self, urb, status);
1643 	usb_anchor_suspend_wakeups(anchor);
1644 	usb_unanchor_urb(urb);
1645 	if (likely(status == 0))
1646 		usb_led_activity(USB_LED_EVENT_HOST);
1647 
1648 	/* pass ownership to the completion handler */
1649 	urb->status = status;
1650 	/*
1651 	 * This function can be called in task context inside another remote
1652 	 * coverage collection section, but kcov doesn't support that kind of
1653 	 * recursion yet. Only collect coverage in softirq context for now.
1654 	 */
1655 	kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
1656 	urb->complete(urb);
1657 	kcov_remote_stop_softirq();
1658 
1659 	usb_anchor_resume_wakeups(anchor);
1660 	atomic_dec(&urb->use_count);
1661 	if (unlikely(atomic_read(&urb->reject)))
1662 		wake_up(&usb_kill_urb_queue);
1663 	usb_put_urb(urb);
1664 }
1665 
usb_giveback_urb_bh(struct tasklet_struct * t)1666 static void usb_giveback_urb_bh(struct tasklet_struct *t)
1667 {
1668 	struct giveback_urb_bh *bh = from_tasklet(bh, t, bh);
1669 	struct list_head local_list;
1670 
1671 	spin_lock_irq(&bh->lock);
1672 	bh->running = true;
1673  restart:
1674 	list_replace_init(&bh->head, &local_list);
1675 	spin_unlock_irq(&bh->lock);
1676 
1677 	while (!list_empty(&local_list)) {
1678 		struct urb *urb;
1679 
1680 		urb = list_entry(local_list.next, struct urb, urb_list);
1681 		list_del_init(&urb->urb_list);
1682 		bh->completing_ep = urb->ep;
1683 		__usb_hcd_giveback_urb(urb);
1684 		bh->completing_ep = NULL;
1685 	}
1686 
1687 	/* check if there are new URBs to giveback */
1688 	spin_lock_irq(&bh->lock);
1689 	if (!list_empty(&bh->head))
1690 		goto restart;
1691 	bh->running = false;
1692 	spin_unlock_irq(&bh->lock);
1693 }
1694 
1695 /**
1696  * usb_hcd_giveback_urb - return URB from HCD to device driver
1697  * @hcd: host controller returning the URB
1698  * @urb: urb being returned to the USB device driver.
1699  * @status: completion status code for the URB.
1700  *
1701  * Context: atomic. The completion callback is invoked in caller's context.
1702  * For HCDs with HCD_BH flag set, the completion callback is invoked in tasklet
1703  * context (except for URBs submitted to the root hub which always complete in
1704  * caller's context).
1705  *
1706  * This hands the URB from HCD to its USB device driver, using its
1707  * completion function.  The HCD has freed all per-urb resources
1708  * (and is done using urb->hcpriv).  It also released all HCD locks;
1709  * the device driver won't cause problems if it frees, modifies,
1710  * or resubmits this URB.
1711  *
1712  * If @urb was unlinked, the value of @status will be overridden by
1713  * @urb->unlinked.  Erroneous short transfers are detected in case
1714  * the HCD hasn't checked for them.
1715  */
usb_hcd_giveback_urb(struct usb_hcd * hcd,struct urb * urb,int status)1716 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1717 {
1718 	struct giveback_urb_bh *bh;
1719 	bool running, high_prio_bh;
1720 
1721 	/* pass status to tasklet via unlinked */
1722 	if (likely(!urb->unlinked))
1723 		urb->unlinked = status;
1724 
1725 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1726 		__usb_hcd_giveback_urb(urb);
1727 		return;
1728 	}
1729 
1730 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1731 		bh = &hcd->high_prio_bh;
1732 		high_prio_bh = true;
1733 	} else {
1734 		bh = &hcd->low_prio_bh;
1735 		high_prio_bh = false;
1736 	}
1737 
1738 	spin_lock(&bh->lock);
1739 	list_add_tail(&urb->urb_list, &bh->head);
1740 	running = bh->running;
1741 	spin_unlock(&bh->lock);
1742 
1743 	if (running)
1744 		;
1745 	else if (high_prio_bh)
1746 		tasklet_hi_schedule(&bh->bh);
1747 	else
1748 		tasklet_schedule(&bh->bh);
1749 }
1750 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1751 
1752 /*-------------------------------------------------------------------------*/
1753 
1754 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1755  * queue to drain completely.  The caller must first insure that no more
1756  * URBs can be submitted for this endpoint.
1757  */
usb_hcd_flush_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)1758 void usb_hcd_flush_endpoint(struct usb_device *udev,
1759 		struct usb_host_endpoint *ep)
1760 {
1761 	struct usb_hcd		*hcd;
1762 	struct urb		*urb;
1763 
1764 	if (!ep)
1765 		return;
1766 	might_sleep();
1767 	hcd = bus_to_hcd(udev->bus);
1768 
1769 	/* No more submits can occur */
1770 	spin_lock_irq(&hcd_urb_list_lock);
1771 rescan:
1772 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1773 		int	is_in;
1774 
1775 		if (urb->unlinked)
1776 			continue;
1777 		usb_get_urb (urb);
1778 		is_in = usb_urb_dir_in(urb);
1779 		spin_unlock(&hcd_urb_list_lock);
1780 
1781 		/* kick hcd */
1782 		unlink1(hcd, urb, -ESHUTDOWN);
1783 		dev_dbg (hcd->self.controller,
1784 			"shutdown urb %pK ep%d%s-%s\n",
1785 			urb, usb_endpoint_num(&ep->desc),
1786 			is_in ? "in" : "out",
1787 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1788 		usb_put_urb (urb);
1789 
1790 		/* list contents may have changed */
1791 		spin_lock(&hcd_urb_list_lock);
1792 		goto rescan;
1793 	}
1794 	spin_unlock_irq(&hcd_urb_list_lock);
1795 
1796 	/* Wait until the endpoint queue is completely empty */
1797 	while (!list_empty (&ep->urb_list)) {
1798 		spin_lock_irq(&hcd_urb_list_lock);
1799 
1800 		/* The list may have changed while we acquired the spinlock */
1801 		urb = NULL;
1802 		if (!list_empty (&ep->urb_list)) {
1803 			urb = list_entry (ep->urb_list.prev, struct urb,
1804 					urb_list);
1805 			usb_get_urb (urb);
1806 		}
1807 		spin_unlock_irq(&hcd_urb_list_lock);
1808 
1809 		if (urb) {
1810 			usb_kill_urb (urb);
1811 			usb_put_urb (urb);
1812 		}
1813 	}
1814 }
1815 
1816 /**
1817  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1818  *				the bus bandwidth
1819  * @udev: target &usb_device
1820  * @new_config: new configuration to install
1821  * @cur_alt: the current alternate interface setting
1822  * @new_alt: alternate interface setting that is being installed
1823  *
1824  * To change configurations, pass in the new configuration in new_config,
1825  * and pass NULL for cur_alt and new_alt.
1826  *
1827  * To reset a device's configuration (put the device in the ADDRESSED state),
1828  * pass in NULL for new_config, cur_alt, and new_alt.
1829  *
1830  * To change alternate interface settings, pass in NULL for new_config,
1831  * pass in the current alternate interface setting in cur_alt,
1832  * and pass in the new alternate interface setting in new_alt.
1833  *
1834  * Return: An error if the requested bandwidth change exceeds the
1835  * bus bandwidth or host controller internal resources.
1836  */
usb_hcd_alloc_bandwidth(struct usb_device * udev,struct usb_host_config * new_config,struct usb_host_interface * cur_alt,struct usb_host_interface * new_alt)1837 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1838 		struct usb_host_config *new_config,
1839 		struct usb_host_interface *cur_alt,
1840 		struct usb_host_interface *new_alt)
1841 {
1842 	int num_intfs, i, j;
1843 	struct usb_host_interface *alt = NULL;
1844 	int ret = 0;
1845 	struct usb_hcd *hcd;
1846 	struct usb_host_endpoint *ep;
1847 
1848 	hcd = bus_to_hcd(udev->bus);
1849 	if (!hcd->driver->check_bandwidth)
1850 		return 0;
1851 
1852 	/* Configuration is being removed - set configuration 0 */
1853 	if (!new_config && !cur_alt) {
1854 		for (i = 1; i < 16; ++i) {
1855 			ep = udev->ep_out[i];
1856 			if (ep)
1857 				hcd->driver->drop_endpoint(hcd, udev, ep);
1858 			ep = udev->ep_in[i];
1859 			if (ep)
1860 				hcd->driver->drop_endpoint(hcd, udev, ep);
1861 		}
1862 		hcd->driver->check_bandwidth(hcd, udev);
1863 		return 0;
1864 	}
1865 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1866 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1867 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1868 	 * ok to exclude it.
1869 	 */
1870 	if (new_config) {
1871 		num_intfs = new_config->desc.bNumInterfaces;
1872 		/* Remove endpoints (except endpoint 0, which is always on the
1873 		 * schedule) from the old config from the schedule
1874 		 */
1875 		for (i = 1; i < 16; ++i) {
1876 			ep = udev->ep_out[i];
1877 			if (ep) {
1878 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1879 				if (ret < 0)
1880 					goto reset;
1881 			}
1882 			ep = udev->ep_in[i];
1883 			if (ep) {
1884 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1885 				if (ret < 0)
1886 					goto reset;
1887 			}
1888 		}
1889 		for (i = 0; i < num_intfs; ++i) {
1890 			struct usb_host_interface *first_alt;
1891 			int iface_num;
1892 
1893 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1894 			iface_num = first_alt->desc.bInterfaceNumber;
1895 			/* Set up endpoints for alternate interface setting 0 */
1896 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1897 			if (!alt)
1898 				/* No alt setting 0? Pick the first setting. */
1899 				alt = first_alt;
1900 
1901 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1902 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1903 				if (ret < 0)
1904 					goto reset;
1905 			}
1906 		}
1907 	}
1908 	if (cur_alt && new_alt) {
1909 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1910 				cur_alt->desc.bInterfaceNumber);
1911 
1912 		if (!iface)
1913 			return -EINVAL;
1914 		if (iface->resetting_device) {
1915 			/*
1916 			 * The USB core just reset the device, so the xHCI host
1917 			 * and the device will think alt setting 0 is installed.
1918 			 * However, the USB core will pass in the alternate
1919 			 * setting installed before the reset as cur_alt.  Dig
1920 			 * out the alternate setting 0 structure, or the first
1921 			 * alternate setting if a broken device doesn't have alt
1922 			 * setting 0.
1923 			 */
1924 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1925 			if (!cur_alt)
1926 				cur_alt = &iface->altsetting[0];
1927 		}
1928 
1929 		/* Drop all the endpoints in the current alt setting */
1930 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1931 			ret = hcd->driver->drop_endpoint(hcd, udev,
1932 					&cur_alt->endpoint[i]);
1933 			if (ret < 0)
1934 				goto reset;
1935 		}
1936 		/* Add all the endpoints in the new alt setting */
1937 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1938 			ret = hcd->driver->add_endpoint(hcd, udev,
1939 					&new_alt->endpoint[i]);
1940 			if (ret < 0)
1941 				goto reset;
1942 		}
1943 	}
1944 	ret = hcd->driver->check_bandwidth(hcd, udev);
1945 reset:
1946 	if (ret < 0)
1947 		hcd->driver->reset_bandwidth(hcd, udev);
1948 	return ret;
1949 }
1950 
1951 /* Disables the endpoint: synchronizes with the hcd to make sure all
1952  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1953  * have been called previously.  Use for set_configuration, set_interface,
1954  * driver removal, physical disconnect.
1955  *
1956  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1957  * type, maxpacket size, toggle, halt status, and scheduling.
1958  */
usb_hcd_disable_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)1959 void usb_hcd_disable_endpoint(struct usb_device *udev,
1960 		struct usb_host_endpoint *ep)
1961 {
1962 	struct usb_hcd		*hcd;
1963 
1964 	might_sleep();
1965 	hcd = bus_to_hcd(udev->bus);
1966 	if (hcd->driver->endpoint_disable)
1967 		hcd->driver->endpoint_disable(hcd, ep);
1968 }
1969 
1970 /**
1971  * usb_hcd_reset_endpoint - reset host endpoint state
1972  * @udev: USB device.
1973  * @ep:   the endpoint to reset.
1974  *
1975  * Resets any host endpoint state such as the toggle bit, sequence
1976  * number and current window.
1977  */
usb_hcd_reset_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)1978 void usb_hcd_reset_endpoint(struct usb_device *udev,
1979 			    struct usb_host_endpoint *ep)
1980 {
1981 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1982 
1983 	if (hcd->driver->endpoint_reset)
1984 		hcd->driver->endpoint_reset(hcd, ep);
1985 	else {
1986 		int epnum = usb_endpoint_num(&ep->desc);
1987 		int is_out = usb_endpoint_dir_out(&ep->desc);
1988 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1989 
1990 		usb_settoggle(udev, epnum, is_out, 0);
1991 		if (is_control)
1992 			usb_settoggle(udev, epnum, !is_out, 0);
1993 	}
1994 }
1995 
1996 /**
1997  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1998  * @interface:		alternate setting that includes all endpoints.
1999  * @eps:		array of endpoints that need streams.
2000  * @num_eps:		number of endpoints in the array.
2001  * @num_streams:	number of streams to allocate.
2002  * @mem_flags:		flags hcd should use to allocate memory.
2003  *
2004  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2005  * Drivers may queue multiple transfers to different stream IDs, which may
2006  * complete in a different order than they were queued.
2007  *
2008  * Return: On success, the number of allocated streams. On failure, a negative
2009  * error code.
2010  */
usb_alloc_streams(struct usb_interface * interface,struct usb_host_endpoint ** eps,unsigned int num_eps,unsigned int num_streams,gfp_t mem_flags)2011 int usb_alloc_streams(struct usb_interface *interface,
2012 		struct usb_host_endpoint **eps, unsigned int num_eps,
2013 		unsigned int num_streams, gfp_t mem_flags)
2014 {
2015 	struct usb_hcd *hcd;
2016 	struct usb_device *dev;
2017 	int i, ret;
2018 
2019 	dev = interface_to_usbdev(interface);
2020 	hcd = bus_to_hcd(dev->bus);
2021 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2022 		return -EINVAL;
2023 	if (dev->speed < USB_SPEED_SUPER)
2024 		return -EINVAL;
2025 	if (dev->state < USB_STATE_CONFIGURED)
2026 		return -ENODEV;
2027 
2028 	for (i = 0; i < num_eps; i++) {
2029 		/* Streams only apply to bulk endpoints. */
2030 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2031 			return -EINVAL;
2032 		/* Re-alloc is not allowed */
2033 		if (eps[i]->streams)
2034 			return -EINVAL;
2035 	}
2036 
2037 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2038 			num_streams, mem_flags);
2039 	if (ret < 0)
2040 		return ret;
2041 
2042 	for (i = 0; i < num_eps; i++)
2043 		eps[i]->streams = ret;
2044 
2045 	return ret;
2046 }
2047 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2048 
2049 /**
2050  * usb_free_streams - free bulk endpoint stream IDs.
2051  * @interface:	alternate setting that includes all endpoints.
2052  * @eps:	array of endpoints to remove streams from.
2053  * @num_eps:	number of endpoints in the array.
2054  * @mem_flags:	flags hcd should use to allocate memory.
2055  *
2056  * Reverts a group of bulk endpoints back to not using stream IDs.
2057  * Can fail if we are given bad arguments, or HCD is broken.
2058  *
2059  * Return: 0 on success. On failure, a negative error code.
2060  */
usb_free_streams(struct usb_interface * interface,struct usb_host_endpoint ** eps,unsigned int num_eps,gfp_t mem_flags)2061 int usb_free_streams(struct usb_interface *interface,
2062 		struct usb_host_endpoint **eps, unsigned int num_eps,
2063 		gfp_t mem_flags)
2064 {
2065 	struct usb_hcd *hcd;
2066 	struct usb_device *dev;
2067 	int i, ret;
2068 
2069 	dev = interface_to_usbdev(interface);
2070 	hcd = bus_to_hcd(dev->bus);
2071 	if (dev->speed < USB_SPEED_SUPER)
2072 		return -EINVAL;
2073 
2074 	/* Double-free is not allowed */
2075 	for (i = 0; i < num_eps; i++)
2076 		if (!eps[i] || !eps[i]->streams)
2077 			return -EINVAL;
2078 
2079 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2080 	if (ret < 0)
2081 		return ret;
2082 
2083 	for (i = 0; i < num_eps; i++)
2084 		eps[i]->streams = 0;
2085 
2086 	return ret;
2087 }
2088 EXPORT_SYMBOL_GPL(usb_free_streams);
2089 
2090 /* Protect against drivers that try to unlink URBs after the device
2091  * is gone, by waiting until all unlinks for @udev are finished.
2092  * Since we don't currently track URBs by device, simply wait until
2093  * nothing is running in the locked region of usb_hcd_unlink_urb().
2094  */
usb_hcd_synchronize_unlinks(struct usb_device * udev)2095 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2096 {
2097 	spin_lock_irq(&hcd_urb_unlink_lock);
2098 	spin_unlock_irq(&hcd_urb_unlink_lock);
2099 }
2100 
2101 /*-------------------------------------------------------------------------*/
2102 
2103 /* called in any context */
usb_hcd_get_frame_number(struct usb_device * udev)2104 int usb_hcd_get_frame_number (struct usb_device *udev)
2105 {
2106 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2107 
2108 	if (!HCD_RH_RUNNING(hcd))
2109 		return -ESHUTDOWN;
2110 	return hcd->driver->get_frame_number (hcd);
2111 }
2112 
2113 /*-------------------------------------------------------------------------*/
2114 
2115 #ifdef	CONFIG_PM
2116 
hcd_bus_suspend(struct usb_device * rhdev,pm_message_t msg)2117 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2118 {
2119 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2120 	int		status;
2121 	int		old_state = hcd->state;
2122 
2123 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2124 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2125 			rhdev->do_remote_wakeup);
2126 	if (HCD_DEAD(hcd)) {
2127 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2128 		return 0;
2129 	}
2130 
2131 	if (!hcd->driver->bus_suspend) {
2132 		status = -ENOENT;
2133 	} else {
2134 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2135 		hcd->state = HC_STATE_QUIESCING;
2136 		status = hcd->driver->bus_suspend(hcd);
2137 	}
2138 	if (status == 0) {
2139 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2140 		hcd->state = HC_STATE_SUSPENDED;
2141 
2142 		if (!PMSG_IS_AUTO(msg))
2143 			usb_phy_roothub_suspend(hcd->self.sysdev,
2144 						hcd->phy_roothub);
2145 
2146 		/* Did we race with a root-hub wakeup event? */
2147 		if (rhdev->do_remote_wakeup) {
2148 			char	buffer[6];
2149 
2150 			status = hcd->driver->hub_status_data(hcd, buffer);
2151 			if (status != 0) {
2152 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2153 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2154 				status = -EBUSY;
2155 			}
2156 		}
2157 	} else {
2158 		spin_lock_irq(&hcd_root_hub_lock);
2159 		if (!HCD_DEAD(hcd)) {
2160 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2161 			hcd->state = old_state;
2162 		}
2163 		spin_unlock_irq(&hcd_root_hub_lock);
2164 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2165 				"suspend", status);
2166 	}
2167 	return status;
2168 }
2169 
hcd_bus_resume(struct usb_device * rhdev,pm_message_t msg)2170 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2171 {
2172 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2173 	int		status;
2174 	int		old_state = hcd->state;
2175 
2176 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2177 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2178 	if (HCD_DEAD(hcd)) {
2179 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2180 		return 0;
2181 	}
2182 
2183 	if (!PMSG_IS_AUTO(msg)) {
2184 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2185 						hcd->phy_roothub);
2186 		if (status)
2187 			return status;
2188 	}
2189 
2190 	if (!hcd->driver->bus_resume)
2191 		return -ENOENT;
2192 	if (HCD_RH_RUNNING(hcd))
2193 		return 0;
2194 
2195 	hcd->state = HC_STATE_RESUMING;
2196 	status = hcd->driver->bus_resume(hcd);
2197 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2198 	if (status == 0)
2199 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2200 
2201 	if (status == 0) {
2202 		struct usb_device *udev;
2203 		int port1;
2204 
2205 		spin_lock_irq(&hcd_root_hub_lock);
2206 		if (!HCD_DEAD(hcd)) {
2207 			usb_set_device_state(rhdev, rhdev->actconfig
2208 					? USB_STATE_CONFIGURED
2209 					: USB_STATE_ADDRESS);
2210 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2211 			hcd->state = HC_STATE_RUNNING;
2212 		}
2213 		spin_unlock_irq(&hcd_root_hub_lock);
2214 
2215 		/*
2216 		 * Check whether any of the enabled ports on the root hub are
2217 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2218 		 * (this is what the USB-2 spec calls a "global resume").
2219 		 * Otherwise we can skip the delay.
2220 		 */
2221 		usb_hub_for_each_child(rhdev, port1, udev) {
2222 			if (udev->state != USB_STATE_NOTATTACHED &&
2223 					!udev->port_is_suspended) {
2224 				usleep_range(10000, 11000);	/* TRSMRCY */
2225 				break;
2226 			}
2227 		}
2228 	} else {
2229 		hcd->state = old_state;
2230 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2231 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2232 				"resume", status);
2233 		if (status != -ESHUTDOWN)
2234 			usb_hc_died(hcd);
2235 	}
2236 	return status;
2237 }
2238 
2239 /* Workqueue routine for root-hub remote wakeup */
hcd_resume_work(struct work_struct * work)2240 static void hcd_resume_work(struct work_struct *work)
2241 {
2242 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2243 	struct usb_device *udev = hcd->self.root_hub;
2244 
2245 	usb_remote_wakeup(udev);
2246 }
2247 
2248 /**
2249  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2250  * @hcd: host controller for this root hub
2251  *
2252  * The USB host controller calls this function when its root hub is
2253  * suspended (with the remote wakeup feature enabled) and a remote
2254  * wakeup request is received.  The routine submits a workqueue request
2255  * to resume the root hub (that is, manage its downstream ports again).
2256  */
usb_hcd_resume_root_hub(struct usb_hcd * hcd)2257 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2258 {
2259 	unsigned long flags;
2260 
2261 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2262 	if (hcd->rh_registered) {
2263 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2264 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2265 		queue_work(pm_wq, &hcd->wakeup_work);
2266 	}
2267 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2268 }
2269 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2270 
2271 #endif	/* CONFIG_PM */
2272 
2273 /*-------------------------------------------------------------------------*/
2274 
2275 #ifdef	CONFIG_USB_OTG
2276 
2277 /**
2278  * usb_bus_start_enum - start immediate enumeration (for OTG)
2279  * @bus: the bus (must use hcd framework)
2280  * @port_num: 1-based number of port; usually bus->otg_port
2281  * Context: atomic
2282  *
2283  * Starts enumeration, with an immediate reset followed later by
2284  * hub_wq identifying and possibly configuring the device.
2285  * This is needed by OTG controller drivers, where it helps meet
2286  * HNP protocol timing requirements for starting a port reset.
2287  *
2288  * Return: 0 if successful.
2289  */
usb_bus_start_enum(struct usb_bus * bus,unsigned port_num)2290 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2291 {
2292 	struct usb_hcd		*hcd;
2293 	int			status = -EOPNOTSUPP;
2294 
2295 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2296 	 * boards with root hubs hooked up to internal devices (instead of
2297 	 * just the OTG port) may need more attention to resetting...
2298 	 */
2299 	hcd = bus_to_hcd(bus);
2300 	if (port_num && hcd->driver->start_port_reset)
2301 		status = hcd->driver->start_port_reset(hcd, port_num);
2302 
2303 	/* allocate hub_wq shortly after (first) root port reset finishes;
2304 	 * it may issue others, until at least 50 msecs have passed.
2305 	 */
2306 	if (status == 0)
2307 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2308 	return status;
2309 }
2310 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2311 
2312 #endif
2313 
2314 /*-------------------------------------------------------------------------*/
2315 
2316 /**
2317  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2318  * @irq: the IRQ being raised
2319  * @__hcd: pointer to the HCD whose IRQ is being signaled
2320  *
2321  * If the controller isn't HALTed, calls the driver's irq handler.
2322  * Checks whether the controller is now dead.
2323  *
2324  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2325  */
usb_hcd_irq(int irq,void * __hcd)2326 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2327 {
2328 	struct usb_hcd		*hcd = __hcd;
2329 	irqreturn_t		rc;
2330 
2331 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2332 		rc = IRQ_NONE;
2333 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2334 		rc = IRQ_NONE;
2335 	else
2336 		rc = IRQ_HANDLED;
2337 
2338 	return rc;
2339 }
2340 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2341 
2342 /*-------------------------------------------------------------------------*/
2343 
2344 /* Workqueue routine for when the root-hub has died. */
hcd_died_work(struct work_struct * work)2345 static void hcd_died_work(struct work_struct *work)
2346 {
2347 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2348 	static char *env[] = {
2349 		"ERROR=DEAD",
2350 		NULL
2351 	};
2352 
2353 	/* Notify user space that the host controller has died */
2354 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2355 }
2356 
2357 /**
2358  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2359  * @hcd: pointer to the HCD representing the controller
2360  *
2361  * This is called by bus glue to report a USB host controller that died
2362  * while operations may still have been pending.  It's called automatically
2363  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2364  *
2365  * Only call this function with the primary HCD.
2366  */
usb_hc_died(struct usb_hcd * hcd)2367 void usb_hc_died (struct usb_hcd *hcd)
2368 {
2369 	unsigned long flags;
2370 
2371 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2372 
2373 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2374 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2375 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2376 	if (hcd->rh_registered) {
2377 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2378 
2379 		/* make hub_wq clean up old urbs and devices */
2380 		usb_set_device_state (hcd->self.root_hub,
2381 				USB_STATE_NOTATTACHED);
2382 		usb_kick_hub_wq(hcd->self.root_hub);
2383 	}
2384 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2385 		hcd = hcd->shared_hcd;
2386 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2387 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2388 		if (hcd->rh_registered) {
2389 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2390 
2391 			/* make hub_wq clean up old urbs and devices */
2392 			usb_set_device_state(hcd->self.root_hub,
2393 					USB_STATE_NOTATTACHED);
2394 			usb_kick_hub_wq(hcd->self.root_hub);
2395 		}
2396 	}
2397 
2398 	/* Handle the case where this function gets called with a shared HCD */
2399 	if (usb_hcd_is_primary_hcd(hcd))
2400 		schedule_work(&hcd->died_work);
2401 	else
2402 		schedule_work(&hcd->primary_hcd->died_work);
2403 
2404 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2405 	/* Make sure that the other roothub is also deallocated. */
2406 }
2407 EXPORT_SYMBOL_GPL (usb_hc_died);
2408 
2409 /*-------------------------------------------------------------------------*/
2410 
init_giveback_urb_bh(struct giveback_urb_bh * bh)2411 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2412 {
2413 
2414 	spin_lock_init(&bh->lock);
2415 	INIT_LIST_HEAD(&bh->head);
2416 	tasklet_setup(&bh->bh, usb_giveback_urb_bh);
2417 }
2418 
__usb_create_hcd(const struct hc_driver * driver,struct device * sysdev,struct device * dev,const char * bus_name,struct usb_hcd * primary_hcd)2419 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2420 		struct device *sysdev, struct device *dev, const char *bus_name,
2421 		struct usb_hcd *primary_hcd)
2422 {
2423 	struct usb_hcd *hcd;
2424 
2425 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2426 	if (!hcd)
2427 		return NULL;
2428 	if (primary_hcd == NULL) {
2429 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2430 				GFP_KERNEL);
2431 		if (!hcd->address0_mutex) {
2432 			kfree(hcd);
2433 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2434 			return NULL;
2435 		}
2436 		mutex_init(hcd->address0_mutex);
2437 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2438 				GFP_KERNEL);
2439 		if (!hcd->bandwidth_mutex) {
2440 			kfree(hcd->address0_mutex);
2441 			kfree(hcd);
2442 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2443 			return NULL;
2444 		}
2445 		mutex_init(hcd->bandwidth_mutex);
2446 		dev_set_drvdata(dev, hcd);
2447 	} else {
2448 		mutex_lock(&usb_port_peer_mutex);
2449 		hcd->address0_mutex = primary_hcd->address0_mutex;
2450 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2451 		hcd->primary_hcd = primary_hcd;
2452 		primary_hcd->primary_hcd = primary_hcd;
2453 		hcd->shared_hcd = primary_hcd;
2454 		primary_hcd->shared_hcd = hcd;
2455 		mutex_unlock(&usb_port_peer_mutex);
2456 	}
2457 
2458 	kref_init(&hcd->kref);
2459 
2460 	usb_bus_init(&hcd->self);
2461 	hcd->self.controller = dev;
2462 	hcd->self.sysdev = sysdev;
2463 	hcd->self.bus_name = bus_name;
2464 
2465 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2466 #ifdef CONFIG_PM
2467 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2468 #endif
2469 
2470 	INIT_WORK(&hcd->died_work, hcd_died_work);
2471 
2472 	hcd->driver = driver;
2473 	hcd->speed = driver->flags & HCD_MASK;
2474 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2475 			"USB Host Controller";
2476 	return hcd;
2477 }
2478 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2479 
2480 /**
2481  * usb_create_shared_hcd - create and initialize an HCD structure
2482  * @driver: HC driver that will use this hcd
2483  * @dev: device for this HC, stored in hcd->self.controller
2484  * @bus_name: value to store in hcd->self.bus_name
2485  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2486  *              PCI device.  Only allocate certain resources for the primary HCD
2487  *
2488  * Context: task context, might sleep.
2489  *
2490  * Allocate a struct usb_hcd, with extra space at the end for the
2491  * HC driver's private data.  Initialize the generic members of the
2492  * hcd structure.
2493  *
2494  * Return: On success, a pointer to the created and initialized HCD structure.
2495  * On failure (e.g. if memory is unavailable), %NULL.
2496  */
usb_create_shared_hcd(const struct hc_driver * driver,struct device * dev,const char * bus_name,struct usb_hcd * primary_hcd)2497 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2498 		struct device *dev, const char *bus_name,
2499 		struct usb_hcd *primary_hcd)
2500 {
2501 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2502 }
2503 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2504 
2505 /**
2506  * usb_create_hcd - create and initialize an HCD structure
2507  * @driver: HC driver that will use this hcd
2508  * @dev: device for this HC, stored in hcd->self.controller
2509  * @bus_name: value to store in hcd->self.bus_name
2510  *
2511  * Context: task context, might sleep.
2512  *
2513  * Allocate a struct usb_hcd, with extra space at the end for the
2514  * HC driver's private data.  Initialize the generic members of the
2515  * hcd structure.
2516  *
2517  * Return: On success, a pointer to the created and initialized HCD
2518  * structure. On failure (e.g. if memory is unavailable), %NULL.
2519  */
usb_create_hcd(const struct hc_driver * driver,struct device * dev,const char * bus_name)2520 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2521 		struct device *dev, const char *bus_name)
2522 {
2523 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2524 }
2525 EXPORT_SYMBOL_GPL(usb_create_hcd);
2526 
2527 /*
2528  * Roothubs that share one PCI device must also share the bandwidth mutex.
2529  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2530  * deallocated.
2531  *
2532  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2533  * freed.  When hcd_release() is called for either hcd in a peer set,
2534  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2535  */
hcd_release(struct kref * kref)2536 static void hcd_release(struct kref *kref)
2537 {
2538 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2539 
2540 	mutex_lock(&usb_port_peer_mutex);
2541 	if (hcd->shared_hcd) {
2542 		struct usb_hcd *peer = hcd->shared_hcd;
2543 
2544 		peer->shared_hcd = NULL;
2545 		peer->primary_hcd = NULL;
2546 	} else {
2547 		kfree(hcd->address0_mutex);
2548 		kfree(hcd->bandwidth_mutex);
2549 	}
2550 	mutex_unlock(&usb_port_peer_mutex);
2551 	kfree(hcd);
2552 }
2553 
usb_get_hcd(struct usb_hcd * hcd)2554 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2555 {
2556 	if (hcd)
2557 		kref_get (&hcd->kref);
2558 	return hcd;
2559 }
2560 EXPORT_SYMBOL_GPL(usb_get_hcd);
2561 
usb_put_hcd(struct usb_hcd * hcd)2562 void usb_put_hcd (struct usb_hcd *hcd)
2563 {
2564 	if (hcd)
2565 		kref_put (&hcd->kref, hcd_release);
2566 }
2567 EXPORT_SYMBOL_GPL(usb_put_hcd);
2568 
usb_hcd_is_primary_hcd(struct usb_hcd * hcd)2569 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2570 {
2571 	if (!hcd->primary_hcd)
2572 		return 1;
2573 	return hcd == hcd->primary_hcd;
2574 }
2575 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2576 
usb_hcd_find_raw_port_number(struct usb_hcd * hcd,int port1)2577 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2578 {
2579 	if (!hcd->driver->find_raw_port_number)
2580 		return port1;
2581 
2582 	return hcd->driver->find_raw_port_number(hcd, port1);
2583 }
2584 
usb_hcd_request_irqs(struct usb_hcd * hcd,unsigned int irqnum,unsigned long irqflags)2585 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2586 		unsigned int irqnum, unsigned long irqflags)
2587 {
2588 	int retval;
2589 
2590 	if (hcd->driver->irq) {
2591 
2592 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2593 				hcd->driver->description, hcd->self.busnum);
2594 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2595 				hcd->irq_descr, hcd);
2596 		if (retval != 0) {
2597 			dev_err(hcd->self.controller,
2598 					"request interrupt %d failed\n",
2599 					irqnum);
2600 			return retval;
2601 		}
2602 		hcd->irq = irqnum;
2603 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2604 				(hcd->driver->flags & HCD_MEMORY) ?
2605 					"io mem" : "io base",
2606 					(unsigned long long)hcd->rsrc_start);
2607 	} else {
2608 		hcd->irq = 0;
2609 		if (hcd->rsrc_start)
2610 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2611 					(hcd->driver->flags & HCD_MEMORY) ?
2612 					"io mem" : "io base",
2613 					(unsigned long long)hcd->rsrc_start);
2614 	}
2615 	return 0;
2616 }
2617 
2618 /*
2619  * Before we free this root hub, flush in-flight peering attempts
2620  * and disable peer lookups
2621  */
usb_put_invalidate_rhdev(struct usb_hcd * hcd)2622 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2623 {
2624 	struct usb_device *rhdev;
2625 
2626 	mutex_lock(&usb_port_peer_mutex);
2627 	rhdev = hcd->self.root_hub;
2628 	hcd->self.root_hub = NULL;
2629 	mutex_unlock(&usb_port_peer_mutex);
2630 	usb_put_dev(rhdev);
2631 }
2632 
2633 /**
2634  * usb_add_hcd - finish generic HCD structure initialization and register
2635  * @hcd: the usb_hcd structure to initialize
2636  * @irqnum: Interrupt line to allocate
2637  * @irqflags: Interrupt type flags
2638  *
2639  * Finish the remaining parts of generic HCD initialization: allocate the
2640  * buffers of consistent memory, register the bus, request the IRQ line,
2641  * and call the driver's reset() and start() routines.
2642  */
usb_add_hcd(struct usb_hcd * hcd,unsigned int irqnum,unsigned long irqflags)2643 int usb_add_hcd(struct usb_hcd *hcd,
2644 		unsigned int irqnum, unsigned long irqflags)
2645 {
2646 	int retval;
2647 	struct usb_device *rhdev;
2648 
2649 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2650 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2651 		if (IS_ERR(hcd->phy_roothub))
2652 			return PTR_ERR(hcd->phy_roothub);
2653 
2654 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2655 		if (retval)
2656 			return retval;
2657 
2658 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2659 						  PHY_MODE_USB_HOST_SS);
2660 		if (retval)
2661 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2662 							  PHY_MODE_USB_HOST);
2663 		if (retval)
2664 			goto err_usb_phy_roothub_power_on;
2665 
2666 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2667 		if (retval)
2668 			goto err_usb_phy_roothub_power_on;
2669 	}
2670 
2671 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2672 
2673 	switch (authorized_default) {
2674 	case USB_AUTHORIZE_NONE:
2675 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2676 		break;
2677 
2678 	case USB_AUTHORIZE_ALL:
2679 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2680 		break;
2681 
2682 	case USB_AUTHORIZE_INTERNAL:
2683 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2684 		break;
2685 
2686 	case USB_AUTHORIZE_WIRED:
2687 	default:
2688 		hcd->dev_policy = hcd->wireless ?
2689 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2690 		break;
2691 	}
2692 
2693 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2694 
2695 	/* per default all interfaces are authorized */
2696 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2697 
2698 	/* HC is in reset state, but accessible.  Now do the one-time init,
2699 	 * bottom up so that hcds can customize the root hubs before hub_wq
2700 	 * starts talking to them.  (Note, bus id is assigned early too.)
2701 	 */
2702 	retval = hcd_buffer_create(hcd);
2703 	if (retval != 0) {
2704 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2705 		goto err_create_buf;
2706 	}
2707 
2708 	retval = usb_register_bus(&hcd->self);
2709 	if (retval < 0)
2710 		goto err_register_bus;
2711 
2712 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2713 	if (rhdev == NULL) {
2714 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2715 		retval = -ENOMEM;
2716 		goto err_allocate_root_hub;
2717 	}
2718 	mutex_lock(&usb_port_peer_mutex);
2719 	hcd->self.root_hub = rhdev;
2720 	mutex_unlock(&usb_port_peer_mutex);
2721 
2722 	rhdev->rx_lanes = 1;
2723 	rhdev->tx_lanes = 1;
2724 	rhdev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2725 
2726 	switch (hcd->speed) {
2727 	case HCD_USB11:
2728 		rhdev->speed = USB_SPEED_FULL;
2729 		break;
2730 	case HCD_USB2:
2731 		rhdev->speed = USB_SPEED_HIGH;
2732 		break;
2733 	case HCD_USB25:
2734 		rhdev->speed = USB_SPEED_WIRELESS;
2735 		break;
2736 	case HCD_USB3:
2737 		rhdev->speed = USB_SPEED_SUPER;
2738 		break;
2739 	case HCD_USB32:
2740 		rhdev->rx_lanes = 2;
2741 		rhdev->tx_lanes = 2;
2742 		rhdev->ssp_rate = USB_SSP_GEN_2x2;
2743 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2744 		break;
2745 	case HCD_USB31:
2746 		rhdev->ssp_rate = USB_SSP_GEN_2x1;
2747 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2748 		break;
2749 	default:
2750 		retval = -EINVAL;
2751 		goto err_set_rh_speed;
2752 	}
2753 
2754 	/* wakeup flag init defaults to "everything works" for root hubs,
2755 	 * but drivers can override it in reset() if needed, along with
2756 	 * recording the overall controller's system wakeup capability.
2757 	 */
2758 	device_set_wakeup_capable(&rhdev->dev, 1);
2759 
2760 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2761 	 * registered.  But since the controller can die at any time,
2762 	 * let's initialize the flag before touching the hardware.
2763 	 */
2764 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2765 
2766 	/* "reset" is misnamed; its role is now one-time init. the controller
2767 	 * should already have been reset (and boot firmware kicked off etc).
2768 	 */
2769 	if (hcd->driver->reset) {
2770 		retval = hcd->driver->reset(hcd);
2771 		if (retval < 0) {
2772 			dev_err(hcd->self.controller, "can't setup: %d\n",
2773 					retval);
2774 			goto err_hcd_driver_setup;
2775 		}
2776 	}
2777 	hcd->rh_pollable = 1;
2778 
2779 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2780 	if (retval)
2781 		goto err_hcd_driver_setup;
2782 
2783 	/* NOTE: root hub and controller capabilities may not be the same */
2784 	if (device_can_wakeup(hcd->self.controller)
2785 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2786 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2787 
2788 	/* initialize tasklets */
2789 	init_giveback_urb_bh(&hcd->high_prio_bh);
2790 	init_giveback_urb_bh(&hcd->low_prio_bh);
2791 
2792 	/* enable irqs just before we start the controller,
2793 	 * if the BIOS provides legacy PCI irqs.
2794 	 */
2795 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2796 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2797 		if (retval)
2798 			goto err_request_irq;
2799 	}
2800 
2801 	hcd->state = HC_STATE_RUNNING;
2802 	retval = hcd->driver->start(hcd);
2803 	if (retval < 0) {
2804 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2805 		goto err_hcd_driver_start;
2806 	}
2807 
2808 	/* starting here, usbcore will pay attention to this root hub */
2809 	retval = register_root_hub(hcd);
2810 	if (retval != 0)
2811 		goto err_register_root_hub;
2812 
2813 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2814 		usb_hcd_poll_rh_status(hcd);
2815 
2816 	return retval;
2817 
2818 err_register_root_hub:
2819 	hcd->rh_pollable = 0;
2820 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2821 	del_timer_sync(&hcd->rh_timer);
2822 	hcd->driver->stop(hcd);
2823 	hcd->state = HC_STATE_HALT;
2824 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2825 	del_timer_sync(&hcd->rh_timer);
2826 err_hcd_driver_start:
2827 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2828 		free_irq(irqnum, hcd);
2829 err_request_irq:
2830 err_hcd_driver_setup:
2831 err_set_rh_speed:
2832 	usb_put_invalidate_rhdev(hcd);
2833 err_allocate_root_hub:
2834 	usb_deregister_bus(&hcd->self);
2835 err_register_bus:
2836 	hcd_buffer_destroy(hcd);
2837 err_create_buf:
2838 	usb_phy_roothub_power_off(hcd->phy_roothub);
2839 err_usb_phy_roothub_power_on:
2840 	usb_phy_roothub_exit(hcd->phy_roothub);
2841 
2842 	return retval;
2843 }
2844 EXPORT_SYMBOL_GPL(usb_add_hcd);
2845 
2846 /**
2847  * usb_remove_hcd - shutdown processing for generic HCDs
2848  * @hcd: the usb_hcd structure to remove
2849  *
2850  * Context: task context, might sleep.
2851  *
2852  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2853  * invoking the HCD's stop() method.
2854  */
usb_remove_hcd(struct usb_hcd * hcd)2855 void usb_remove_hcd(struct usb_hcd *hcd)
2856 {
2857 	struct usb_device *rhdev = hcd->self.root_hub;
2858 
2859 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2860 
2861 	usb_get_dev(rhdev);
2862 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2863 	if (HC_IS_RUNNING (hcd->state))
2864 		hcd->state = HC_STATE_QUIESCING;
2865 
2866 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2867 	spin_lock_irq (&hcd_root_hub_lock);
2868 	hcd->rh_registered = 0;
2869 	spin_unlock_irq (&hcd_root_hub_lock);
2870 
2871 #ifdef CONFIG_PM
2872 	cancel_work_sync(&hcd->wakeup_work);
2873 #endif
2874 	cancel_work_sync(&hcd->died_work);
2875 
2876 	mutex_lock(&usb_bus_idr_lock);
2877 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2878 	mutex_unlock(&usb_bus_idr_lock);
2879 
2880 	/*
2881 	 * tasklet_kill() isn't needed here because:
2882 	 * - driver's disconnect() called from usb_disconnect() should
2883 	 *   make sure its URBs are completed during the disconnect()
2884 	 *   callback
2885 	 *
2886 	 * - it is too late to run complete() here since driver may have
2887 	 *   been removed already now
2888 	 */
2889 
2890 	/* Prevent any more root-hub status calls from the timer.
2891 	 * The HCD might still restart the timer (if a port status change
2892 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2893 	 * the hub_status_data() callback.
2894 	 */
2895 	hcd->rh_pollable = 0;
2896 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2897 	del_timer_sync(&hcd->rh_timer);
2898 
2899 	hcd->driver->stop(hcd);
2900 	hcd->state = HC_STATE_HALT;
2901 
2902 	/* In case the HCD restarted the timer, stop it again. */
2903 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2904 	del_timer_sync(&hcd->rh_timer);
2905 
2906 	if (usb_hcd_is_primary_hcd(hcd)) {
2907 		if (hcd->irq > 0)
2908 			free_irq(hcd->irq, hcd);
2909 	}
2910 
2911 	usb_deregister_bus(&hcd->self);
2912 	hcd_buffer_destroy(hcd);
2913 
2914 	usb_phy_roothub_power_off(hcd->phy_roothub);
2915 	usb_phy_roothub_exit(hcd->phy_roothub);
2916 
2917 	usb_put_invalidate_rhdev(hcd);
2918 	hcd->flags = 0;
2919 }
2920 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2921 
2922 void
usb_hcd_platform_shutdown(struct platform_device * dev)2923 usb_hcd_platform_shutdown(struct platform_device *dev)
2924 {
2925 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2926 
2927 	/* No need for pm_runtime_put(), we're shutting down */
2928 	pm_runtime_get_sync(&dev->dev);
2929 
2930 	if (hcd->driver->shutdown)
2931 		hcd->driver->shutdown(hcd);
2932 }
2933 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2934 
usb_hcd_setup_local_mem(struct usb_hcd * hcd,phys_addr_t phys_addr,dma_addr_t dma,size_t size)2935 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2936 			    dma_addr_t dma, size_t size)
2937 {
2938 	int err;
2939 	void *local_mem;
2940 
2941 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2942 						  dev_to_node(hcd->self.sysdev),
2943 						  dev_name(hcd->self.sysdev));
2944 	if (IS_ERR(hcd->localmem_pool))
2945 		return PTR_ERR(hcd->localmem_pool);
2946 
2947 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2948 				  size, MEMREMAP_WC);
2949 	if (IS_ERR(local_mem))
2950 		return PTR_ERR(local_mem);
2951 
2952 	/*
2953 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2954 	 * It's not backed by system memory and thus there's no kernel mapping
2955 	 * for it.
2956 	 */
2957 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2958 				dma, size, dev_to_node(hcd->self.sysdev));
2959 	if (err < 0) {
2960 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2961 			err);
2962 		return err;
2963 	}
2964 
2965 	return 0;
2966 }
2967 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2968 
2969 /*-------------------------------------------------------------------------*/
2970 
2971 #if IS_ENABLED(CONFIG_USB_MON)
2972 
2973 const struct usb_mon_operations *mon_ops;
2974 
2975 /*
2976  * The registration is unlocked.
2977  * We do it this way because we do not want to lock in hot paths.
2978  *
2979  * Notice that the code is minimally error-proof. Because usbmon needs
2980  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2981  */
2982 
usb_mon_register(const struct usb_mon_operations * ops)2983 int usb_mon_register(const struct usb_mon_operations *ops)
2984 {
2985 
2986 	if (mon_ops)
2987 		return -EBUSY;
2988 
2989 	mon_ops = ops;
2990 	mb();
2991 	return 0;
2992 }
2993 EXPORT_SYMBOL_GPL (usb_mon_register);
2994 
usb_mon_deregister(void)2995 void usb_mon_deregister (void)
2996 {
2997 
2998 	if (mon_ops == NULL) {
2999 		printk(KERN_ERR "USB: monitor was not registered\n");
3000 		return;
3001 	}
3002 	mon_ops = NULL;
3003 	mb();
3004 }
3005 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3006 
3007 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3008