xref: /linux/drivers/usb/gadget/udc/udc-xilinx.c (revision d642ef71)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Xilinx USB peripheral controller driver
4  *
5  * Copyright (C) 2004 by Thomas Rathbone
6  * Copyright (C) 2005 by HP Labs
7  * Copyright (C) 2005 by David Brownell
8  * Copyright (C) 2010 - 2014 Xilinx, Inc.
9  *
10  * Some parts of this driver code is based on the driver for at91-series
11  * USB peripheral controller (at91_udc.c).
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/device.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/platform_device.h>
23 #include <linux/prefetch.h>
24 #include <linux/usb/ch9.h>
25 #include <linux/usb/gadget.h>
26 
27 /* Register offsets for the USB device.*/
28 #define XUSB_EP0_CONFIG_OFFSET		0x0000  /* EP0 Config Reg Offset */
29 #define XUSB_SETUP_PKT_ADDR_OFFSET	0x0080  /* Setup Packet Address */
30 #define XUSB_ADDRESS_OFFSET		0x0100  /* Address Register */
31 #define XUSB_CONTROL_OFFSET		0x0104  /* Control Register */
32 #define XUSB_STATUS_OFFSET		0x0108  /* Status Register */
33 #define XUSB_FRAMENUM_OFFSET		0x010C	/* Frame Number Register */
34 #define XUSB_IER_OFFSET			0x0110	/* Interrupt Enable Register */
35 #define XUSB_BUFFREADY_OFFSET		0x0114	/* Buffer Ready Register */
36 #define XUSB_TESTMODE_OFFSET		0x0118	/* Test Mode Register */
37 #define XUSB_DMA_RESET_OFFSET		0x0200  /* DMA Soft Reset Register */
38 #define XUSB_DMA_CONTROL_OFFSET		0x0204	/* DMA Control Register */
39 #define XUSB_DMA_DSAR_ADDR_OFFSET	0x0208	/* DMA source Address Reg */
40 #define XUSB_DMA_DDAR_ADDR_OFFSET	0x020C	/* DMA destination Addr Reg */
41 #define XUSB_DMA_LENGTH_OFFSET		0x0210	/* DMA Length Register */
42 #define XUSB_DMA_STATUS_OFFSET		0x0214	/* DMA Status Register */
43 
44 /* Endpoint Configuration Space offsets */
45 #define XUSB_EP_CFGSTATUS_OFFSET	0x00	/* Endpoint Config Status  */
46 #define XUSB_EP_BUF0COUNT_OFFSET	0x08	/* Buffer 0 Count */
47 #define XUSB_EP_BUF1COUNT_OFFSET	0x0C	/* Buffer 1 Count */
48 
49 #define XUSB_CONTROL_USB_READY_MASK	0x80000000 /* USB ready Mask */
50 #define XUSB_CONTROL_USB_RMTWAKE_MASK	0x40000000 /* Remote wake up mask */
51 
52 /* Interrupt register related masks.*/
53 #define XUSB_STATUS_GLOBAL_INTR_MASK	0x80000000 /* Global Intr Enable */
54 #define XUSB_STATUS_DMADONE_MASK	0x04000000 /* DMA done Mask */
55 #define XUSB_STATUS_DMAERR_MASK		0x02000000 /* DMA Error Mask */
56 #define XUSB_STATUS_DMABUSY_MASK	0x80000000 /* DMA Error Mask */
57 #define XUSB_STATUS_RESUME_MASK		0x01000000 /* USB Resume Mask */
58 #define XUSB_STATUS_RESET_MASK		0x00800000 /* USB Reset Mask */
59 #define XUSB_STATUS_SUSPEND_MASK	0x00400000 /* USB Suspend Mask */
60 #define XUSB_STATUS_DISCONNECT_MASK	0x00200000 /* USB Disconnect Mask */
61 #define XUSB_STATUS_FIFO_BUFF_RDY_MASK	0x00100000 /* FIFO Buff Ready Mask */
62 #define XUSB_STATUS_FIFO_BUFF_FREE_MASK	0x00080000 /* FIFO Buff Free Mask */
63 #define XUSB_STATUS_SETUP_PACKET_MASK	0x00040000 /* Setup packet received */
64 #define XUSB_STATUS_EP1_BUFF2_COMP_MASK	0x00000200 /* EP 1 Buff 2 Processed */
65 #define XUSB_STATUS_EP1_BUFF1_COMP_MASK	0x00000002 /* EP 1 Buff 1 Processed */
66 #define XUSB_STATUS_EP0_BUFF2_COMP_MASK	0x00000100 /* EP 0 Buff 2 Processed */
67 #define XUSB_STATUS_EP0_BUFF1_COMP_MASK	0x00000001 /* EP 0 Buff 1 Processed */
68 #define XUSB_STATUS_HIGH_SPEED_MASK	0x00010000 /* USB Speed Mask */
69 /* Suspend,Reset,Suspend and Disconnect Mask */
70 #define XUSB_STATUS_INTR_EVENT_MASK	0x01E00000
71 /* Buffers  completion Mask */
72 #define XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK	0x0000FEFF
73 /* Mask for buffer 0 and buffer 1 completion for all Endpoints */
74 #define XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK	0x00000101
75 #define XUSB_STATUS_EP_BUFF2_SHIFT	8	   /* EP buffer offset */
76 
77 /* Endpoint Configuration Status Register */
78 #define XUSB_EP_CFG_VALID_MASK		0x80000000 /* Endpoint Valid bit */
79 #define XUSB_EP_CFG_STALL_MASK		0x40000000 /* Endpoint Stall bit */
80 #define XUSB_EP_CFG_DATA_TOGGLE_MASK	0x08000000 /* Endpoint Data toggle */
81 
82 /* USB device specific global configuration constants.*/
83 #define XUSB_MAX_ENDPOINTS		8	/* Maximum End Points */
84 #define XUSB_EP_NUMBER_ZERO		0	/* End point Zero */
85 /* DPRAM is the source address for DMA transfer */
86 #define XUSB_DMA_READ_FROM_DPRAM	0x80000000
87 #define XUSB_DMA_DMASR_BUSY		0x80000000 /* DMA busy */
88 #define XUSB_DMA_DMASR_ERROR		0x40000000 /* DMA Error */
89 /*
90  * When this bit is set, the DMA buffer ready bit is set by hardware upon
91  * DMA transfer completion.
92  */
93 #define XUSB_DMA_BRR_CTRL		0x40000000 /* DMA bufready ctrl bit */
94 /* Phase States */
95 #define SETUP_PHASE			0x0000	/* Setup Phase */
96 #define DATA_PHASE			0x0001  /* Data Phase */
97 #define STATUS_PHASE			0x0002  /* Status Phase */
98 
99 #define EP0_MAX_PACKET		64 /* Endpoint 0 maximum packet length */
100 #define STATUSBUFF_SIZE		2  /* Buffer size for GET_STATUS command */
101 #define EPNAME_SIZE		4  /* Buffer size for endpoint name */
102 
103 /* container_of helper macros */
104 #define to_udc(g)	 container_of((g), struct xusb_udc, gadget)
105 #define to_xusb_ep(ep)	 container_of((ep), struct xusb_ep, ep_usb)
106 #define to_xusb_req(req) container_of((req), struct xusb_req, usb_req)
107 
108 /**
109  * struct xusb_req - Xilinx USB device request structure
110  * @usb_req: Linux usb request structure
111  * @queue: usb device request queue
112  * @ep: pointer to xusb_endpoint structure
113  */
114 struct xusb_req {
115 	struct usb_request usb_req;
116 	struct list_head queue;
117 	struct xusb_ep *ep;
118 };
119 
120 /**
121  * struct xusb_ep - USB end point structure.
122  * @ep_usb: usb endpoint instance
123  * @queue: endpoint message queue
124  * @udc: xilinx usb peripheral driver instance pointer
125  * @desc: pointer to the usb endpoint descriptor
126  * @rambase: the endpoint buffer address
127  * @offset: the endpoint register offset value
128  * @name: name of the endpoint
129  * @epnumber: endpoint number
130  * @maxpacket: maximum packet size the endpoint can store
131  * @buffer0count: the size of the packet recieved in the first buffer
132  * @buffer1count: the size of the packet received in the second buffer
133  * @curbufnum: current buffer of endpoint that will be processed next
134  * @buffer0ready: the busy state of first buffer
135  * @buffer1ready: the busy state of second buffer
136  * @is_in: endpoint direction (IN or OUT)
137  * @is_iso: endpoint type(isochronous or non isochronous)
138  */
139 struct xusb_ep {
140 	struct usb_ep ep_usb;
141 	struct list_head queue;
142 	struct xusb_udc *udc;
143 	const struct usb_endpoint_descriptor *desc;
144 	u32  rambase;
145 	u32  offset;
146 	char name[4];
147 	u16  epnumber;
148 	u16  maxpacket;
149 	u16  buffer0count;
150 	u16  buffer1count;
151 	u8   curbufnum;
152 	bool buffer0ready;
153 	bool buffer1ready;
154 	bool is_in;
155 	bool is_iso;
156 };
157 
158 /**
159  * struct xusb_udc -  USB peripheral driver structure
160  * @gadget: USB gadget driver instance
161  * @ep: an array of endpoint structures
162  * @driver: pointer to the usb gadget driver instance
163  * @setup: usb_ctrlrequest structure for control requests
164  * @req: pointer to dummy request for get status command
165  * @dev: pointer to device structure in gadget
166  * @usb_state: device in suspended state or not
167  * @remote_wkp: remote wakeup enabled by host
168  * @setupseqtx: tx status
169  * @setupseqrx: rx status
170  * @addr: the usb device base address
171  * @lock: instance of spinlock
172  * @dma_enabled: flag indicating whether the dma is included in the system
173  * @clk: pointer to struct clk
174  * @read_fn: function pointer to read device registers
175  * @write_fn: function pointer to write to device registers
176  */
177 struct xusb_udc {
178 	struct usb_gadget gadget;
179 	struct xusb_ep ep[8];
180 	struct usb_gadget_driver *driver;
181 	struct usb_ctrlrequest setup;
182 	struct xusb_req *req;
183 	struct device *dev;
184 	u32 usb_state;
185 	u32 remote_wkp;
186 	u32 setupseqtx;
187 	u32 setupseqrx;
188 	void __iomem *addr;
189 	spinlock_t lock;
190 	bool dma_enabled;
191 	struct clk *clk;
192 
193 	unsigned int (*read_fn)(void __iomem *reg);
194 	void (*write_fn)(void __iomem *, u32, u32);
195 };
196 
197 /* Endpoint buffer start addresses in the core */
198 static u32 rambase[8] = { 0x22, 0x1000, 0x1100, 0x1200, 0x1300, 0x1400, 0x1500,
199 			  0x1600 };
200 
201 static const char driver_name[] = "xilinx-udc";
202 static const char ep0name[] = "ep0";
203 
204 /* Control endpoint configuration.*/
205 static const struct usb_endpoint_descriptor config_bulk_out_desc = {
206 	.bLength		= USB_DT_ENDPOINT_SIZE,
207 	.bDescriptorType	= USB_DT_ENDPOINT,
208 	.bEndpointAddress	= USB_DIR_OUT,
209 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
210 	.wMaxPacketSize		= cpu_to_le16(EP0_MAX_PACKET),
211 };
212 
213 /**
214  * xudc_write32 - little endian write to device registers
215  * @addr: base addr of device registers
216  * @offset: register offset
217  * @val: data to be written
218  */
219 static void xudc_write32(void __iomem *addr, u32 offset, u32 val)
220 {
221 	iowrite32(val, addr + offset);
222 }
223 
224 /**
225  * xudc_read32 - little endian read from device registers
226  * @addr: addr of device register
227  * Return: value at addr
228  */
229 static unsigned int xudc_read32(void __iomem *addr)
230 {
231 	return ioread32(addr);
232 }
233 
234 /**
235  * xudc_write32_be - big endian write to device registers
236  * @addr: base addr of device registers
237  * @offset: register offset
238  * @val: data to be written
239  */
240 static void xudc_write32_be(void __iomem *addr, u32 offset, u32 val)
241 {
242 	iowrite32be(val, addr + offset);
243 }
244 
245 /**
246  * xudc_read32_be - big endian read from device registers
247  * @addr: addr of device register
248  * Return: value at addr
249  */
250 static unsigned int xudc_read32_be(void __iomem *addr)
251 {
252 	return ioread32be(addr);
253 }
254 
255 /**
256  * xudc_wrstatus - Sets up the usb device status stages.
257  * @udc: pointer to the usb device controller structure.
258  */
259 static void xudc_wrstatus(struct xusb_udc *udc)
260 {
261 	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
262 	u32 epcfgreg;
263 
264 	epcfgreg = udc->read_fn(udc->addr + ep0->offset)|
265 				XUSB_EP_CFG_DATA_TOGGLE_MASK;
266 	udc->write_fn(udc->addr, ep0->offset, epcfgreg);
267 	udc->write_fn(udc->addr, ep0->offset + XUSB_EP_BUF0COUNT_OFFSET, 0);
268 	udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
269 }
270 
271 /**
272  * xudc_epconfig - Configures the given endpoint.
273  * @ep: pointer to the usb device endpoint structure.
274  * @udc: pointer to the usb peripheral controller structure.
275  *
276  * This function configures a specific endpoint with the given configuration
277  * data.
278  */
279 static void xudc_epconfig(struct xusb_ep *ep, struct xusb_udc *udc)
280 {
281 	u32 epcfgreg;
282 
283 	/*
284 	 * Configure the end point direction, type, Max Packet Size and the
285 	 * EP buffer location.
286 	 */
287 	epcfgreg = ((ep->is_in << 29) | (ep->is_iso << 28) |
288 		   (ep->ep_usb.maxpacket << 15) | (ep->rambase));
289 	udc->write_fn(udc->addr, ep->offset, epcfgreg);
290 
291 	/* Set the Buffer count and the Buffer ready bits.*/
292 	udc->write_fn(udc->addr, ep->offset + XUSB_EP_BUF0COUNT_OFFSET,
293 		      ep->buffer0count);
294 	udc->write_fn(udc->addr, ep->offset + XUSB_EP_BUF1COUNT_OFFSET,
295 		      ep->buffer1count);
296 	if (ep->buffer0ready)
297 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
298 			      1 << ep->epnumber);
299 	if (ep->buffer1ready)
300 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
301 			      1 << (ep->epnumber + XUSB_STATUS_EP_BUFF2_SHIFT));
302 }
303 
304 /**
305  * xudc_start_dma - Starts DMA transfer.
306  * @ep: pointer to the usb device endpoint structure.
307  * @src: DMA source address.
308  * @dst: DMA destination address.
309  * @length: number of bytes to transfer.
310  *
311  * Return: 0 on success, error code on failure
312  *
313  * This function starts DMA transfer by writing to DMA source,
314  * destination and lenth registers.
315  */
316 static int xudc_start_dma(struct xusb_ep *ep, dma_addr_t src,
317 			  dma_addr_t dst, u32 length)
318 {
319 	struct xusb_udc *udc = ep->udc;
320 	int rc = 0;
321 	u32 timeout = 500;
322 	u32 reg;
323 
324 	/*
325 	 * Set the addresses in the DMA source and
326 	 * destination registers and then set the length
327 	 * into the DMA length register.
328 	 */
329 	udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
330 	udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
331 	udc->write_fn(udc->addr, XUSB_DMA_LENGTH_OFFSET, length);
332 
333 	/*
334 	 * Wait till DMA transaction is complete and
335 	 * check whether the DMA transaction was
336 	 * successful.
337 	 */
338 	do {
339 		reg = udc->read_fn(udc->addr + XUSB_DMA_STATUS_OFFSET);
340 		if (!(reg &  XUSB_DMA_DMASR_BUSY))
341 			break;
342 
343 		/*
344 		 * We can't sleep here, because it's also called from
345 		 * interrupt context.
346 		 */
347 		timeout--;
348 		if (!timeout) {
349 			dev_err(udc->dev, "DMA timeout\n");
350 			return -ETIMEDOUT;
351 		}
352 		udelay(1);
353 	} while (1);
354 
355 	if ((udc->read_fn(udc->addr + XUSB_DMA_STATUS_OFFSET) &
356 			  XUSB_DMA_DMASR_ERROR) == XUSB_DMA_DMASR_ERROR){
357 		dev_err(udc->dev, "DMA Error\n");
358 		rc = -EINVAL;
359 	}
360 
361 	return rc;
362 }
363 
364 /**
365  * xudc_dma_send - Sends IN data using DMA.
366  * @ep: pointer to the usb device endpoint structure.
367  * @req: pointer to the usb request structure.
368  * @buffer: pointer to data to be sent.
369  * @length: number of bytes to send.
370  *
371  * Return: 0 on success, -EAGAIN if no buffer is free and error
372  *	   code on failure.
373  *
374  * This function sends data using DMA.
375  */
376 static int xudc_dma_send(struct xusb_ep *ep, struct xusb_req *req,
377 			 u8 *buffer, u32 length)
378 {
379 	u32 *eprambase;
380 	dma_addr_t src;
381 	dma_addr_t dst;
382 	struct xusb_udc *udc = ep->udc;
383 
384 	src = req->usb_req.dma + req->usb_req.actual;
385 	if (req->usb_req.length)
386 		dma_sync_single_for_device(udc->dev, src,
387 					   length, DMA_TO_DEVICE);
388 	if (!ep->curbufnum && !ep->buffer0ready) {
389 		/* Get the Buffer address and copy the transmit data.*/
390 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
391 		dst = virt_to_phys(eprambase);
392 		udc->write_fn(udc->addr, ep->offset +
393 			      XUSB_EP_BUF0COUNT_OFFSET, length);
394 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
395 			      XUSB_DMA_BRR_CTRL | (1 << ep->epnumber));
396 		ep->buffer0ready = 1;
397 		ep->curbufnum = 1;
398 	} else if (ep->curbufnum && !ep->buffer1ready) {
399 		/* Get the Buffer address and copy the transmit data.*/
400 		eprambase = (u32 __force *)(udc->addr + ep->rambase +
401 			     ep->ep_usb.maxpacket);
402 		dst = virt_to_phys(eprambase);
403 		udc->write_fn(udc->addr, ep->offset +
404 			      XUSB_EP_BUF1COUNT_OFFSET, length);
405 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
406 			      XUSB_DMA_BRR_CTRL | (1 << (ep->epnumber +
407 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
408 		ep->buffer1ready = 1;
409 		ep->curbufnum = 0;
410 	} else {
411 		/* None of ping pong buffers are ready currently .*/
412 		return -EAGAIN;
413 	}
414 
415 	return xudc_start_dma(ep, src, dst, length);
416 }
417 
418 /**
419  * xudc_dma_receive - Receives OUT data using DMA.
420  * @ep: pointer to the usb device endpoint structure.
421  * @req: pointer to the usb request structure.
422  * @buffer: pointer to storage buffer of received data.
423  * @length: number of bytes to receive.
424  *
425  * Return: 0 on success, -EAGAIN if no buffer is free and error
426  *	   code on failure.
427  *
428  * This function receives data using DMA.
429  */
430 static int xudc_dma_receive(struct xusb_ep *ep, struct xusb_req *req,
431 			    u8 *buffer, u32 length)
432 {
433 	u32 *eprambase;
434 	dma_addr_t src;
435 	dma_addr_t dst;
436 	struct xusb_udc *udc = ep->udc;
437 
438 	dst = req->usb_req.dma + req->usb_req.actual;
439 	if (!ep->curbufnum && !ep->buffer0ready) {
440 		/* Get the Buffer address and copy the transmit data */
441 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
442 		src = virt_to_phys(eprambase);
443 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
444 			      XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
445 			      (1 << ep->epnumber));
446 		ep->buffer0ready = 1;
447 		ep->curbufnum = 1;
448 	} else if (ep->curbufnum && !ep->buffer1ready) {
449 		/* Get the Buffer address and copy the transmit data */
450 		eprambase = (u32 __force *)(udc->addr +
451 			     ep->rambase + ep->ep_usb.maxpacket);
452 		src = virt_to_phys(eprambase);
453 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
454 			      XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
455 			      (1 << (ep->epnumber +
456 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
457 		ep->buffer1ready = 1;
458 		ep->curbufnum = 0;
459 	} else {
460 		/* None of the ping-pong buffers are ready currently */
461 		return -EAGAIN;
462 	}
463 
464 	return xudc_start_dma(ep, src, dst, length);
465 }
466 
467 /**
468  * xudc_eptxrx - Transmits or receives data to or from an endpoint.
469  * @ep: pointer to the usb endpoint configuration structure.
470  * @req: pointer to the usb request structure.
471  * @bufferptr: pointer to buffer containing the data to be sent.
472  * @bufferlen: The number of data bytes to be sent.
473  *
474  * Return: 0 on success, -EAGAIN if no buffer is free.
475  *
476  * This function copies the transmit/receive data to/from the end point buffer
477  * and enables the buffer for transmission/reception.
478  */
479 static int xudc_eptxrx(struct xusb_ep *ep, struct xusb_req *req,
480 		       u8 *bufferptr, u32 bufferlen)
481 {
482 	u32 *eprambase;
483 	u32 bytestosend;
484 	int rc = 0;
485 	struct xusb_udc *udc = ep->udc;
486 
487 	bytestosend = bufferlen;
488 	if (udc->dma_enabled) {
489 		if (ep->is_in)
490 			rc = xudc_dma_send(ep, req, bufferptr, bufferlen);
491 		else
492 			rc = xudc_dma_receive(ep, req, bufferptr, bufferlen);
493 		return rc;
494 	}
495 	/* Put the transmit buffer into the correct ping-pong buffer.*/
496 	if (!ep->curbufnum && !ep->buffer0ready) {
497 		/* Get the Buffer address and copy the transmit data.*/
498 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
499 		if (ep->is_in) {
500 			memcpy_toio((void __iomem *)eprambase, bufferptr,
501 				    bytestosend);
502 			udc->write_fn(udc->addr, ep->offset +
503 				      XUSB_EP_BUF0COUNT_OFFSET, bufferlen);
504 		} else {
505 			memcpy_toio((void __iomem *)bufferptr, eprambase,
506 				    bytestosend);
507 		}
508 		/*
509 		 * Enable the buffer for transmission.
510 		 */
511 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
512 			      1 << ep->epnumber);
513 		ep->buffer0ready = 1;
514 		ep->curbufnum = 1;
515 	} else if (ep->curbufnum && !ep->buffer1ready) {
516 		/* Get the Buffer address and copy the transmit data.*/
517 		eprambase = (u32 __force *)(udc->addr + ep->rambase +
518 			     ep->ep_usb.maxpacket);
519 		if (ep->is_in) {
520 			memcpy_toio((void __iomem *)eprambase, bufferptr,
521 				    bytestosend);
522 			udc->write_fn(udc->addr, ep->offset +
523 				      XUSB_EP_BUF1COUNT_OFFSET, bufferlen);
524 		} else {
525 			memcpy_toio((void __iomem *)bufferptr, eprambase,
526 				    bytestosend);
527 		}
528 		/*
529 		 * Enable the buffer for transmission.
530 		 */
531 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
532 			      1 << (ep->epnumber + XUSB_STATUS_EP_BUFF2_SHIFT));
533 		ep->buffer1ready = 1;
534 		ep->curbufnum = 0;
535 	} else {
536 		/* None of the ping-pong buffers are ready currently */
537 		return -EAGAIN;
538 	}
539 	return rc;
540 }
541 
542 /**
543  * xudc_done - Exeutes the endpoint data transfer completion tasks.
544  * @ep: pointer to the usb device endpoint structure.
545  * @req: pointer to the usb request structure.
546  * @status: Status of the data transfer.
547  *
548  * Deletes the message from the queue and updates data transfer completion
549  * status.
550  */
551 static void xudc_done(struct xusb_ep *ep, struct xusb_req *req, int status)
552 {
553 	struct xusb_udc *udc = ep->udc;
554 
555 	list_del_init(&req->queue);
556 
557 	if (req->usb_req.status == -EINPROGRESS)
558 		req->usb_req.status = status;
559 	else
560 		status = req->usb_req.status;
561 
562 	if (status && status != -ESHUTDOWN)
563 		dev_dbg(udc->dev, "%s done %p, status %d\n",
564 			ep->ep_usb.name, req, status);
565 	/* unmap request if DMA is present*/
566 	if (udc->dma_enabled && ep->epnumber && req->usb_req.length)
567 		usb_gadget_unmap_request(&udc->gadget, &req->usb_req,
568 					 ep->is_in);
569 
570 	if (req->usb_req.complete) {
571 		spin_unlock(&udc->lock);
572 		req->usb_req.complete(&ep->ep_usb, &req->usb_req);
573 		spin_lock(&udc->lock);
574 	}
575 }
576 
577 /**
578  * xudc_read_fifo - Reads the data from the given endpoint buffer.
579  * @ep: pointer to the usb device endpoint structure.
580  * @req: pointer to the usb request structure.
581  *
582  * Return: 0 if request is completed and -EAGAIN if not completed.
583  *
584  * Pulls OUT packet data from the endpoint buffer.
585  */
586 static int xudc_read_fifo(struct xusb_ep *ep, struct xusb_req *req)
587 {
588 	u8 *buf;
589 	u32 is_short, count, bufferspace;
590 	u8 bufoffset;
591 	u8 two_pkts = 0;
592 	int ret;
593 	int retval = -EAGAIN;
594 	struct xusb_udc *udc = ep->udc;
595 
596 	if (ep->buffer0ready && ep->buffer1ready) {
597 		dev_dbg(udc->dev, "Packet NOT ready!\n");
598 		return retval;
599 	}
600 top:
601 	if (ep->curbufnum)
602 		bufoffset = XUSB_EP_BUF1COUNT_OFFSET;
603 	else
604 		bufoffset = XUSB_EP_BUF0COUNT_OFFSET;
605 
606 	count = udc->read_fn(udc->addr + ep->offset + bufoffset);
607 
608 	if (!ep->buffer0ready && !ep->buffer1ready)
609 		two_pkts = 1;
610 
611 	buf = req->usb_req.buf + req->usb_req.actual;
612 	prefetchw(buf);
613 	bufferspace = req->usb_req.length - req->usb_req.actual;
614 	is_short = count < ep->ep_usb.maxpacket;
615 
616 	if (unlikely(!bufferspace)) {
617 		/*
618 		 * This happens when the driver's buffer
619 		 * is smaller than what the host sent.
620 		 * discard the extra data.
621 		 */
622 		if (req->usb_req.status != -EOVERFLOW)
623 			dev_dbg(udc->dev, "%s overflow %d\n",
624 				ep->ep_usb.name, count);
625 		req->usb_req.status = -EOVERFLOW;
626 		xudc_done(ep, req, -EOVERFLOW);
627 		return 0;
628 	}
629 
630 	ret = xudc_eptxrx(ep, req, buf, count);
631 	switch (ret) {
632 	case 0:
633 		req->usb_req.actual += min(count, bufferspace);
634 		dev_dbg(udc->dev, "read %s, %d bytes%s req %p %d/%d\n",
635 			ep->ep_usb.name, count, is_short ? "/S" : "", req,
636 			req->usb_req.actual, req->usb_req.length);
637 
638 		/* Completion */
639 		if ((req->usb_req.actual == req->usb_req.length) || is_short) {
640 			if (udc->dma_enabled && req->usb_req.length)
641 				dma_sync_single_for_cpu(udc->dev,
642 							req->usb_req.dma,
643 							req->usb_req.actual,
644 							DMA_FROM_DEVICE);
645 			xudc_done(ep, req, 0);
646 			return 0;
647 		}
648 		if (two_pkts) {
649 			two_pkts = 0;
650 			goto top;
651 		}
652 		break;
653 	case -EAGAIN:
654 		dev_dbg(udc->dev, "receive busy\n");
655 		break;
656 	case -EINVAL:
657 	case -ETIMEDOUT:
658 		/* DMA error, dequeue the request */
659 		xudc_done(ep, req, -ECONNRESET);
660 		retval = 0;
661 		break;
662 	}
663 
664 	return retval;
665 }
666 
667 /**
668  * xudc_write_fifo - Writes data into the given endpoint buffer.
669  * @ep: pointer to the usb device endpoint structure.
670  * @req: pointer to the usb request structure.
671  *
672  * Return: 0 if request is completed and -EAGAIN if not completed.
673  *
674  * Loads endpoint buffer for an IN packet.
675  */
676 static int xudc_write_fifo(struct xusb_ep *ep, struct xusb_req *req)
677 {
678 	u32 max;
679 	u32 length;
680 	int ret;
681 	int retval = -EAGAIN;
682 	struct xusb_udc *udc = ep->udc;
683 	int is_last, is_short = 0;
684 	u8 *buf;
685 
686 	max = le16_to_cpu(ep->desc->wMaxPacketSize);
687 	buf = req->usb_req.buf + req->usb_req.actual;
688 	prefetch(buf);
689 	length = req->usb_req.length - req->usb_req.actual;
690 	length = min(length, max);
691 
692 	ret = xudc_eptxrx(ep, req, buf, length);
693 	switch (ret) {
694 	case 0:
695 		req->usb_req.actual += length;
696 		if (unlikely(length != max)) {
697 			is_last = is_short = 1;
698 		} else {
699 			if (likely(req->usb_req.length !=
700 				   req->usb_req.actual) || req->usb_req.zero)
701 				is_last = 0;
702 			else
703 				is_last = 1;
704 		}
705 		dev_dbg(udc->dev, "%s: wrote %s %d bytes%s%s %d left %p\n",
706 			__func__, ep->ep_usb.name, length, is_last ? "/L" : "",
707 			is_short ? "/S" : "",
708 			req->usb_req.length - req->usb_req.actual, req);
709 		/* completion */
710 		if (is_last) {
711 			xudc_done(ep, req, 0);
712 			retval = 0;
713 		}
714 		break;
715 	case -EAGAIN:
716 		dev_dbg(udc->dev, "Send busy\n");
717 		break;
718 	case -EINVAL:
719 	case -ETIMEDOUT:
720 		/* DMA error, dequeue the request */
721 		xudc_done(ep, req, -ECONNRESET);
722 		retval = 0;
723 		break;
724 	}
725 
726 	return retval;
727 }
728 
729 /**
730  * xudc_nuke - Cleans up the data transfer message list.
731  * @ep: pointer to the usb device endpoint structure.
732  * @status: Status of the data transfer.
733  */
734 static void xudc_nuke(struct xusb_ep *ep, int status)
735 {
736 	struct xusb_req *req;
737 
738 	while (!list_empty(&ep->queue)) {
739 		req = list_first_entry(&ep->queue, struct xusb_req, queue);
740 		xudc_done(ep, req, status);
741 	}
742 }
743 
744 /**
745  * xudc_ep_set_halt - Stalls/unstalls the given endpoint.
746  * @_ep: pointer to the usb device endpoint structure.
747  * @value: value to indicate stall/unstall.
748  *
749  * Return: 0 for success and error value on failure
750  */
751 static int xudc_ep_set_halt(struct usb_ep *_ep, int value)
752 {
753 	struct xusb_ep *ep = to_xusb_ep(_ep);
754 	struct xusb_udc *udc;
755 	unsigned long flags;
756 	u32 epcfgreg;
757 
758 	if (!_ep || (!ep->desc && ep->epnumber)) {
759 		pr_debug("%s: bad ep or descriptor\n", __func__);
760 		return -EINVAL;
761 	}
762 	udc = ep->udc;
763 
764 	if (ep->is_in && (!list_empty(&ep->queue)) && value) {
765 		dev_dbg(udc->dev, "requests pending can't halt\n");
766 		return -EAGAIN;
767 	}
768 
769 	if (ep->buffer0ready || ep->buffer1ready) {
770 		dev_dbg(udc->dev, "HW buffers busy can't halt\n");
771 		return -EAGAIN;
772 	}
773 
774 	spin_lock_irqsave(&udc->lock, flags);
775 
776 	if (value) {
777 		/* Stall the device.*/
778 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
779 		epcfgreg |= XUSB_EP_CFG_STALL_MASK;
780 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
781 	} else {
782 		/* Unstall the device.*/
783 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
784 		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
785 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
786 		if (ep->epnumber) {
787 			/* Reset the toggle bit.*/
788 			epcfgreg = udc->read_fn(ep->udc->addr + ep->offset);
789 			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
790 			udc->write_fn(udc->addr, ep->offset, epcfgreg);
791 		}
792 	}
793 
794 	spin_unlock_irqrestore(&udc->lock, flags);
795 	return 0;
796 }
797 
798 /**
799  * __xudc_ep_enable - Enables the given endpoint.
800  * @ep: pointer to the xusb endpoint structure.
801  * @desc: pointer to usb endpoint descriptor.
802  *
803  * Return: 0 for success and error value on failure
804  */
805 static int __xudc_ep_enable(struct xusb_ep *ep,
806 			    const struct usb_endpoint_descriptor *desc)
807 {
808 	struct xusb_udc *udc = ep->udc;
809 	u32 tmp;
810 	u32 epcfg;
811 	u32 ier;
812 	u16 maxpacket;
813 
814 	ep->is_in = ((desc->bEndpointAddress & USB_DIR_IN) != 0);
815 	/* Bit 3...0:endpoint number */
816 	ep->epnumber = (desc->bEndpointAddress & 0x0f);
817 	ep->desc = desc;
818 	ep->ep_usb.desc = desc;
819 	tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
820 	ep->ep_usb.maxpacket = maxpacket = le16_to_cpu(desc->wMaxPacketSize);
821 
822 	switch (tmp) {
823 	case USB_ENDPOINT_XFER_CONTROL:
824 		dev_dbg(udc->dev, "only one control endpoint\n");
825 		/* NON- ISO */
826 		ep->is_iso = 0;
827 		return -EINVAL;
828 	case USB_ENDPOINT_XFER_INT:
829 		/* NON- ISO */
830 		ep->is_iso = 0;
831 		if (maxpacket > 64) {
832 			dev_dbg(udc->dev, "bogus maxpacket %d\n", maxpacket);
833 			return -EINVAL;
834 		}
835 		break;
836 	case USB_ENDPOINT_XFER_BULK:
837 		/* NON- ISO */
838 		ep->is_iso = 0;
839 		if (!(is_power_of_2(maxpacket) && maxpacket >= 8 &&
840 				maxpacket <= 512)) {
841 			dev_dbg(udc->dev, "bogus maxpacket %d\n", maxpacket);
842 			return -EINVAL;
843 		}
844 		break;
845 	case USB_ENDPOINT_XFER_ISOC:
846 		/* ISO */
847 		ep->is_iso = 1;
848 		break;
849 	}
850 
851 	ep->buffer0ready = false;
852 	ep->buffer1ready = false;
853 	ep->curbufnum = 0;
854 	ep->rambase = rambase[ep->epnumber];
855 	xudc_epconfig(ep, udc);
856 
857 	dev_dbg(udc->dev, "Enable Endpoint %d max pkt is %d\n",
858 		ep->epnumber, maxpacket);
859 
860 	/* Enable the End point.*/
861 	epcfg = udc->read_fn(udc->addr + ep->offset);
862 	epcfg |= XUSB_EP_CFG_VALID_MASK;
863 	udc->write_fn(udc->addr, ep->offset, epcfg);
864 	if (ep->epnumber)
865 		ep->rambase <<= 2;
866 
867 	/* Enable buffer completion interrupts for endpoint */
868 	ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
869 	ier |= (XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK << ep->epnumber);
870 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
871 
872 	/* for OUT endpoint set buffers ready to receive */
873 	if (ep->epnumber && !ep->is_in) {
874 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
875 			      1 << ep->epnumber);
876 		ep->buffer0ready = true;
877 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
878 			     (1 << (ep->epnumber +
879 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
880 		ep->buffer1ready = true;
881 	}
882 
883 	return 0;
884 }
885 
886 /**
887  * xudc_ep_enable - Enables the given endpoint.
888  * @_ep: pointer to the usb endpoint structure.
889  * @desc: pointer to usb endpoint descriptor.
890  *
891  * Return: 0 for success and error value on failure
892  */
893 static int xudc_ep_enable(struct usb_ep *_ep,
894 			  const struct usb_endpoint_descriptor *desc)
895 {
896 	struct xusb_ep *ep;
897 	struct xusb_udc *udc;
898 	unsigned long flags;
899 	int ret;
900 
901 	if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
902 		pr_debug("%s: bad ep or descriptor\n", __func__);
903 		return -EINVAL;
904 	}
905 
906 	ep = to_xusb_ep(_ep);
907 	udc = ep->udc;
908 
909 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
910 		dev_dbg(udc->dev, "bogus device state\n");
911 		return -ESHUTDOWN;
912 	}
913 
914 	spin_lock_irqsave(&udc->lock, flags);
915 	ret = __xudc_ep_enable(ep, desc);
916 	spin_unlock_irqrestore(&udc->lock, flags);
917 
918 	return ret;
919 }
920 
921 /**
922  * xudc_ep_disable - Disables the given endpoint.
923  * @_ep: pointer to the usb endpoint structure.
924  *
925  * Return: 0 for success and error value on failure
926  */
927 static int xudc_ep_disable(struct usb_ep *_ep)
928 {
929 	struct xusb_ep *ep;
930 	unsigned long flags;
931 	u32 epcfg;
932 	struct xusb_udc *udc;
933 
934 	if (!_ep) {
935 		pr_debug("%s: invalid ep\n", __func__);
936 		return -EINVAL;
937 	}
938 
939 	ep = to_xusb_ep(_ep);
940 	udc = ep->udc;
941 
942 	spin_lock_irqsave(&udc->lock, flags);
943 
944 	xudc_nuke(ep, -ESHUTDOWN);
945 
946 	/* Restore the endpoint's pristine config */
947 	ep->desc = NULL;
948 	ep->ep_usb.desc = NULL;
949 
950 	dev_dbg(udc->dev, "USB Ep %d disable\n ", ep->epnumber);
951 	/* Disable the endpoint.*/
952 	epcfg = udc->read_fn(udc->addr + ep->offset);
953 	epcfg &= ~XUSB_EP_CFG_VALID_MASK;
954 	udc->write_fn(udc->addr, ep->offset, epcfg);
955 
956 	spin_unlock_irqrestore(&udc->lock, flags);
957 	return 0;
958 }
959 
960 /**
961  * xudc_ep_alloc_request - Initializes the request queue.
962  * @_ep: pointer to the usb endpoint structure.
963  * @gfp_flags: Flags related to the request call.
964  *
965  * Return: pointer to request structure on success and a NULL on failure.
966  */
967 static struct usb_request *xudc_ep_alloc_request(struct usb_ep *_ep,
968 						 gfp_t gfp_flags)
969 {
970 	struct xusb_ep *ep = to_xusb_ep(_ep);
971 	struct xusb_req *req;
972 
973 	req = kzalloc(sizeof(*req), gfp_flags);
974 	if (!req)
975 		return NULL;
976 
977 	req->ep = ep;
978 	INIT_LIST_HEAD(&req->queue);
979 	return &req->usb_req;
980 }
981 
982 /**
983  * xudc_free_request - Releases the request from queue.
984  * @_ep: pointer to the usb device endpoint structure.
985  * @_req: pointer to the usb request structure.
986  */
987 static void xudc_free_request(struct usb_ep *_ep, struct usb_request *_req)
988 {
989 	struct xusb_req *req = to_xusb_req(_req);
990 
991 	kfree(req);
992 }
993 
994 /**
995  * __xudc_ep0_queue - Adds the request to endpoint 0 queue.
996  * @ep0: pointer to the xusb endpoint 0 structure.
997  * @req: pointer to the xusb request structure.
998  *
999  * Return: 0 for success and error value on failure
1000  */
1001 static int __xudc_ep0_queue(struct xusb_ep *ep0, struct xusb_req *req)
1002 {
1003 	struct xusb_udc *udc = ep0->udc;
1004 	u32 length;
1005 	u8 *corebuf;
1006 
1007 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1008 		dev_dbg(udc->dev, "%s, bogus device state\n", __func__);
1009 		return -EINVAL;
1010 	}
1011 	if (!list_empty(&ep0->queue)) {
1012 		dev_dbg(udc->dev, "%s:ep0 busy\n", __func__);
1013 		return -EBUSY;
1014 	}
1015 
1016 	req->usb_req.status = -EINPROGRESS;
1017 	req->usb_req.actual = 0;
1018 
1019 	list_add_tail(&req->queue, &ep0->queue);
1020 
1021 	if (udc->setup.bRequestType & USB_DIR_IN) {
1022 		prefetch(req->usb_req.buf);
1023 		length = req->usb_req.length;
1024 		corebuf = (void __force *) ((ep0->rambase << 2) +
1025 			   udc->addr);
1026 		length = req->usb_req.actual = min_t(u32, length,
1027 						     EP0_MAX_PACKET);
1028 		memcpy_toio((void __iomem *)corebuf, req->usb_req.buf, length);
1029 		udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, length);
1030 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1031 	} else {
1032 		if (udc->setup.wLength) {
1033 			/* Enable EP0 buffer to receive data */
1034 			udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, 0);
1035 			udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1036 		} else {
1037 			xudc_wrstatus(udc);
1038 		}
1039 	}
1040 
1041 	return 0;
1042 }
1043 
1044 /**
1045  * xudc_ep0_queue - Adds the request to endpoint 0 queue.
1046  * @_ep: pointer to the usb endpoint 0 structure.
1047  * @_req: pointer to the usb request structure.
1048  * @gfp_flags: Flags related to the request call.
1049  *
1050  * Return: 0 for success and error value on failure
1051  */
1052 static int xudc_ep0_queue(struct usb_ep *_ep, struct usb_request *_req,
1053 			  gfp_t gfp_flags)
1054 {
1055 	struct xusb_req *req	= to_xusb_req(_req);
1056 	struct xusb_ep	*ep0	= to_xusb_ep(_ep);
1057 	struct xusb_udc *udc	= ep0->udc;
1058 	unsigned long flags;
1059 	int ret;
1060 
1061 	spin_lock_irqsave(&udc->lock, flags);
1062 	ret = __xudc_ep0_queue(ep0, req);
1063 	spin_unlock_irqrestore(&udc->lock, flags);
1064 
1065 	return ret;
1066 }
1067 
1068 /**
1069  * xudc_ep_queue - Adds the request to endpoint queue.
1070  * @_ep: pointer to the usb endpoint structure.
1071  * @_req: pointer to the usb request structure.
1072  * @gfp_flags: Flags related to the request call.
1073  *
1074  * Return: 0 for success and error value on failure
1075  */
1076 static int xudc_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
1077 			 gfp_t gfp_flags)
1078 {
1079 	struct xusb_req *req = to_xusb_req(_req);
1080 	struct xusb_ep	*ep  = to_xusb_ep(_ep);
1081 	struct xusb_udc *udc = ep->udc;
1082 	int  ret;
1083 	unsigned long flags;
1084 
1085 	if (!ep->desc) {
1086 		dev_dbg(udc->dev, "%s: queuing request to disabled %s\n",
1087 			__func__, ep->name);
1088 		return -ESHUTDOWN;
1089 	}
1090 
1091 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1092 		dev_dbg(udc->dev, "%s, bogus device state\n", __func__);
1093 		return -EINVAL;
1094 	}
1095 
1096 	spin_lock_irqsave(&udc->lock, flags);
1097 
1098 	_req->status = -EINPROGRESS;
1099 	_req->actual = 0;
1100 
1101 	if (udc->dma_enabled) {
1102 		ret = usb_gadget_map_request(&udc->gadget, &req->usb_req,
1103 					     ep->is_in);
1104 		if (ret) {
1105 			dev_dbg(udc->dev, "gadget_map failed ep%d\n",
1106 				ep->epnumber);
1107 			spin_unlock_irqrestore(&udc->lock, flags);
1108 			return -EAGAIN;
1109 		}
1110 	}
1111 
1112 	if (list_empty(&ep->queue)) {
1113 		if (ep->is_in) {
1114 			dev_dbg(udc->dev, "xudc_write_fifo from ep_queue\n");
1115 			if (!xudc_write_fifo(ep, req))
1116 				req = NULL;
1117 		} else {
1118 			dev_dbg(udc->dev, "xudc_read_fifo from ep_queue\n");
1119 			if (!xudc_read_fifo(ep, req))
1120 				req = NULL;
1121 		}
1122 	}
1123 
1124 	if (req != NULL)
1125 		list_add_tail(&req->queue, &ep->queue);
1126 
1127 	spin_unlock_irqrestore(&udc->lock, flags);
1128 	return 0;
1129 }
1130 
1131 /**
1132  * xudc_ep_dequeue - Removes the request from the queue.
1133  * @_ep: pointer to the usb device endpoint structure.
1134  * @_req: pointer to the usb request structure.
1135  *
1136  * Return: 0 for success and error value on failure
1137  */
1138 static int xudc_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1139 {
1140 	struct xusb_ep *ep	= to_xusb_ep(_ep);
1141 	struct xusb_req *req	= NULL;
1142 	struct xusb_req *iter;
1143 	struct xusb_udc *udc	= ep->udc;
1144 	unsigned long flags;
1145 
1146 	spin_lock_irqsave(&udc->lock, flags);
1147 	/* Make sure it's actually queued on this endpoint */
1148 	list_for_each_entry(iter, &ep->queue, queue) {
1149 		if (&iter->usb_req != _req)
1150 			continue;
1151 		req = iter;
1152 		break;
1153 	}
1154 	if (!req) {
1155 		spin_unlock_irqrestore(&udc->lock, flags);
1156 		return -EINVAL;
1157 	}
1158 	xudc_done(ep, req, -ECONNRESET);
1159 	spin_unlock_irqrestore(&udc->lock, flags);
1160 
1161 	return 0;
1162 }
1163 
1164 /**
1165  * xudc_ep0_enable - Enables the given endpoint.
1166  * @ep: pointer to the usb endpoint structure.
1167  * @desc: pointer to usb endpoint descriptor.
1168  *
1169  * Return: error always.
1170  *
1171  * endpoint 0 enable should not be called by gadget layer.
1172  */
1173 static int xudc_ep0_enable(struct usb_ep *ep,
1174 			   const struct usb_endpoint_descriptor *desc)
1175 {
1176 	return -EINVAL;
1177 }
1178 
1179 /**
1180  * xudc_ep0_disable - Disables the given endpoint.
1181  * @ep: pointer to the usb endpoint structure.
1182  *
1183  * Return: error always.
1184  *
1185  * endpoint 0 disable should not be called by gadget layer.
1186  */
1187 static int xudc_ep0_disable(struct usb_ep *ep)
1188 {
1189 	return -EINVAL;
1190 }
1191 
1192 static const struct usb_ep_ops xusb_ep0_ops = {
1193 	.enable		= xudc_ep0_enable,
1194 	.disable	= xudc_ep0_disable,
1195 	.alloc_request	= xudc_ep_alloc_request,
1196 	.free_request	= xudc_free_request,
1197 	.queue		= xudc_ep0_queue,
1198 	.dequeue	= xudc_ep_dequeue,
1199 	.set_halt	= xudc_ep_set_halt,
1200 };
1201 
1202 static const struct usb_ep_ops xusb_ep_ops = {
1203 	.enable		= xudc_ep_enable,
1204 	.disable	= xudc_ep_disable,
1205 	.alloc_request	= xudc_ep_alloc_request,
1206 	.free_request	= xudc_free_request,
1207 	.queue		= xudc_ep_queue,
1208 	.dequeue	= xudc_ep_dequeue,
1209 	.set_halt	= xudc_ep_set_halt,
1210 };
1211 
1212 /**
1213  * xudc_get_frame - Reads the current usb frame number.
1214  * @gadget: pointer to the usb gadget structure.
1215  *
1216  * Return: current frame number for success and error value on failure.
1217  */
1218 static int xudc_get_frame(struct usb_gadget *gadget)
1219 {
1220 	struct xusb_udc *udc;
1221 	int frame;
1222 
1223 	if (!gadget)
1224 		return -ENODEV;
1225 
1226 	udc = to_udc(gadget);
1227 	frame = udc->read_fn(udc->addr + XUSB_FRAMENUM_OFFSET);
1228 	return frame;
1229 }
1230 
1231 /**
1232  * xudc_wakeup - Send remote wakeup signal to host
1233  * @gadget: pointer to the usb gadget structure.
1234  *
1235  * Return: 0 on success and error on failure
1236  */
1237 static int xudc_wakeup(struct usb_gadget *gadget)
1238 {
1239 	struct xusb_udc *udc = to_udc(gadget);
1240 	u32 crtlreg;
1241 	int status = -EINVAL;
1242 	unsigned long flags;
1243 
1244 	spin_lock_irqsave(&udc->lock, flags);
1245 
1246 	/* Remote wake up not enabled by host */
1247 	if (!udc->remote_wkp)
1248 		goto done;
1249 
1250 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
1251 	crtlreg |= XUSB_CONTROL_USB_RMTWAKE_MASK;
1252 	/* set remote wake up bit */
1253 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1254 	/*
1255 	 * wait for a while and reset remote wake up bit since this bit
1256 	 * is not cleared by HW after sending remote wakeup to host.
1257 	 */
1258 	mdelay(2);
1259 
1260 	crtlreg &= ~XUSB_CONTROL_USB_RMTWAKE_MASK;
1261 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1262 	status = 0;
1263 done:
1264 	spin_unlock_irqrestore(&udc->lock, flags);
1265 	return status;
1266 }
1267 
1268 /**
1269  * xudc_pullup - start/stop USB traffic
1270  * @gadget: pointer to the usb gadget structure.
1271  * @is_on: flag to start or stop
1272  *
1273  * Return: 0 always
1274  *
1275  * This function starts/stops SIE engine of IP based on is_on.
1276  */
1277 static int xudc_pullup(struct usb_gadget *gadget, int is_on)
1278 {
1279 	struct xusb_udc *udc = to_udc(gadget);
1280 	unsigned long flags;
1281 	u32 crtlreg;
1282 
1283 	spin_lock_irqsave(&udc->lock, flags);
1284 
1285 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
1286 	if (is_on)
1287 		crtlreg |= XUSB_CONTROL_USB_READY_MASK;
1288 	else
1289 		crtlreg &= ~XUSB_CONTROL_USB_READY_MASK;
1290 
1291 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1292 
1293 	spin_unlock_irqrestore(&udc->lock, flags);
1294 
1295 	return 0;
1296 }
1297 
1298 /**
1299  * xudc_eps_init - initialize endpoints.
1300  * @udc: pointer to the usb device controller structure.
1301  */
1302 static void xudc_eps_init(struct xusb_udc *udc)
1303 {
1304 	u32 ep_number;
1305 
1306 	INIT_LIST_HEAD(&udc->gadget.ep_list);
1307 
1308 	for (ep_number = 0; ep_number < XUSB_MAX_ENDPOINTS; ep_number++) {
1309 		struct xusb_ep *ep = &udc->ep[ep_number];
1310 
1311 		if (ep_number) {
1312 			list_add_tail(&ep->ep_usb.ep_list,
1313 				      &udc->gadget.ep_list);
1314 			usb_ep_set_maxpacket_limit(&ep->ep_usb,
1315 						  (unsigned short) ~0);
1316 			snprintf(ep->name, EPNAME_SIZE, "ep%d", ep_number);
1317 			ep->ep_usb.name = ep->name;
1318 			ep->ep_usb.ops = &xusb_ep_ops;
1319 
1320 			ep->ep_usb.caps.type_iso = true;
1321 			ep->ep_usb.caps.type_bulk = true;
1322 			ep->ep_usb.caps.type_int = true;
1323 		} else {
1324 			ep->ep_usb.name = ep0name;
1325 			usb_ep_set_maxpacket_limit(&ep->ep_usb, EP0_MAX_PACKET);
1326 			ep->ep_usb.ops = &xusb_ep0_ops;
1327 
1328 			ep->ep_usb.caps.type_control = true;
1329 		}
1330 
1331 		ep->ep_usb.caps.dir_in = true;
1332 		ep->ep_usb.caps.dir_out = true;
1333 
1334 		ep->udc = udc;
1335 		ep->epnumber = ep_number;
1336 		ep->desc = NULL;
1337 		/*
1338 		 * The configuration register address offset between
1339 		 * each endpoint is 0x10.
1340 		 */
1341 		ep->offset = XUSB_EP0_CONFIG_OFFSET + (ep_number * 0x10);
1342 		ep->is_in = 0;
1343 		ep->is_iso = 0;
1344 		ep->maxpacket = 0;
1345 		xudc_epconfig(ep, udc);
1346 
1347 		/* Initialize one queue per endpoint */
1348 		INIT_LIST_HEAD(&ep->queue);
1349 	}
1350 }
1351 
1352 /**
1353  * xudc_stop_activity - Stops any further activity on the device.
1354  * @udc: pointer to the usb device controller structure.
1355  */
1356 static void xudc_stop_activity(struct xusb_udc *udc)
1357 {
1358 	int i;
1359 	struct xusb_ep *ep;
1360 
1361 	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
1362 		ep = &udc->ep[i];
1363 		xudc_nuke(ep, -ESHUTDOWN);
1364 	}
1365 }
1366 
1367 /**
1368  * xudc_start - Starts the device.
1369  * @gadget: pointer to the usb gadget structure
1370  * @driver: pointer to gadget driver structure
1371  *
1372  * Return: zero on success and error on failure
1373  */
1374 static int xudc_start(struct usb_gadget *gadget,
1375 		      struct usb_gadget_driver *driver)
1376 {
1377 	struct xusb_udc *udc	= to_udc(gadget);
1378 	struct xusb_ep *ep0	= &udc->ep[XUSB_EP_NUMBER_ZERO];
1379 	const struct usb_endpoint_descriptor *desc = &config_bulk_out_desc;
1380 	unsigned long flags;
1381 	int ret = 0;
1382 
1383 	spin_lock_irqsave(&udc->lock, flags);
1384 
1385 	if (udc->driver) {
1386 		dev_err(udc->dev, "%s is already bound to %s\n",
1387 			udc->gadget.name, udc->driver->driver.name);
1388 		ret = -EBUSY;
1389 		goto err;
1390 	}
1391 
1392 	/* hook up the driver */
1393 	udc->driver = driver;
1394 	udc->gadget.speed = driver->max_speed;
1395 
1396 	/* Enable the control endpoint. */
1397 	ret = __xudc_ep_enable(ep0, desc);
1398 
1399 	/* Set device address and remote wakeup to 0 */
1400 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1401 	udc->remote_wkp = 0;
1402 err:
1403 	spin_unlock_irqrestore(&udc->lock, flags);
1404 	return ret;
1405 }
1406 
1407 /**
1408  * xudc_stop - stops the device.
1409  * @gadget: pointer to the usb gadget structure
1410  *
1411  * Return: zero always
1412  */
1413 static int xudc_stop(struct usb_gadget *gadget)
1414 {
1415 	struct xusb_udc *udc = to_udc(gadget);
1416 	unsigned long flags;
1417 
1418 	spin_lock_irqsave(&udc->lock, flags);
1419 
1420 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1421 	udc->driver = NULL;
1422 
1423 	/* Set device address and remote wakeup to 0 */
1424 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1425 	udc->remote_wkp = 0;
1426 
1427 	xudc_stop_activity(udc);
1428 
1429 	spin_unlock_irqrestore(&udc->lock, flags);
1430 
1431 	return 0;
1432 }
1433 
1434 static const struct usb_gadget_ops xusb_udc_ops = {
1435 	.get_frame	= xudc_get_frame,
1436 	.wakeup		= xudc_wakeup,
1437 	.pullup		= xudc_pullup,
1438 	.udc_start	= xudc_start,
1439 	.udc_stop	= xudc_stop,
1440 };
1441 
1442 /**
1443  * xudc_clear_stall_all_ep - clears stall of every endpoint.
1444  * @udc: pointer to the udc structure.
1445  */
1446 static void xudc_clear_stall_all_ep(struct xusb_udc *udc)
1447 {
1448 	struct xusb_ep *ep;
1449 	u32 epcfgreg;
1450 	int i;
1451 
1452 	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
1453 		ep = &udc->ep[i];
1454 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
1455 		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
1456 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
1457 		if (ep->epnumber) {
1458 			/* Reset the toggle bit.*/
1459 			epcfgreg = udc->read_fn(udc->addr + ep->offset);
1460 			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
1461 			udc->write_fn(udc->addr, ep->offset, epcfgreg);
1462 		}
1463 	}
1464 }
1465 
1466 /**
1467  * xudc_startup_handler - The usb device controller interrupt handler.
1468  * @udc: pointer to the udc structure.
1469  * @intrstatus: The mask value containing the interrupt sources.
1470  *
1471  * This function handles the RESET,SUSPEND,RESUME and DISCONNECT interrupts.
1472  */
1473 static void xudc_startup_handler(struct xusb_udc *udc, u32 intrstatus)
1474 {
1475 	u32 intrreg;
1476 
1477 	if (intrstatus & XUSB_STATUS_RESET_MASK) {
1478 
1479 		dev_dbg(udc->dev, "Reset\n");
1480 
1481 		if (intrstatus & XUSB_STATUS_HIGH_SPEED_MASK)
1482 			udc->gadget.speed = USB_SPEED_HIGH;
1483 		else
1484 			udc->gadget.speed = USB_SPEED_FULL;
1485 
1486 		xudc_stop_activity(udc);
1487 		xudc_clear_stall_all_ep(udc);
1488 		udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, 0);
1489 
1490 		/* Set device address and remote wakeup to 0 */
1491 		udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1492 		udc->remote_wkp = 0;
1493 
1494 		/* Enable the suspend, resume and disconnect */
1495 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1496 		intrreg |= XUSB_STATUS_SUSPEND_MASK | XUSB_STATUS_RESUME_MASK |
1497 			   XUSB_STATUS_DISCONNECT_MASK;
1498 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1499 	}
1500 	if (intrstatus & XUSB_STATUS_SUSPEND_MASK) {
1501 
1502 		dev_dbg(udc->dev, "Suspend\n");
1503 
1504 		/* Enable the reset, resume and disconnect */
1505 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1506 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
1507 			   XUSB_STATUS_DISCONNECT_MASK;
1508 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1509 
1510 		udc->usb_state = USB_STATE_SUSPENDED;
1511 
1512 		if (udc->driver->suspend) {
1513 			spin_unlock(&udc->lock);
1514 			udc->driver->suspend(&udc->gadget);
1515 			spin_lock(&udc->lock);
1516 		}
1517 	}
1518 	if (intrstatus & XUSB_STATUS_RESUME_MASK) {
1519 		bool condition = (udc->usb_state != USB_STATE_SUSPENDED);
1520 
1521 		dev_WARN_ONCE(udc->dev, condition,
1522 				"Resume IRQ while not suspended\n");
1523 
1524 		dev_dbg(udc->dev, "Resume\n");
1525 
1526 		/* Enable the reset, suspend and disconnect */
1527 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1528 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_SUSPEND_MASK |
1529 			   XUSB_STATUS_DISCONNECT_MASK;
1530 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1531 
1532 		udc->usb_state = 0;
1533 
1534 		if (udc->driver->resume) {
1535 			spin_unlock(&udc->lock);
1536 			udc->driver->resume(&udc->gadget);
1537 			spin_lock(&udc->lock);
1538 		}
1539 	}
1540 	if (intrstatus & XUSB_STATUS_DISCONNECT_MASK) {
1541 
1542 		dev_dbg(udc->dev, "Disconnect\n");
1543 
1544 		/* Enable the reset, resume and suspend */
1545 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1546 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
1547 			   XUSB_STATUS_SUSPEND_MASK;
1548 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1549 
1550 		if (udc->driver && udc->driver->disconnect) {
1551 			spin_unlock(&udc->lock);
1552 			udc->driver->disconnect(&udc->gadget);
1553 			spin_lock(&udc->lock);
1554 		}
1555 	}
1556 }
1557 
1558 /**
1559  * xudc_ep0_stall - Stall endpoint zero.
1560  * @udc: pointer to the udc structure.
1561  *
1562  * This function stalls endpoint zero.
1563  */
1564 static void xudc_ep0_stall(struct xusb_udc *udc)
1565 {
1566 	u32 epcfgreg;
1567 	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
1568 
1569 	epcfgreg = udc->read_fn(udc->addr + ep0->offset);
1570 	epcfgreg |= XUSB_EP_CFG_STALL_MASK;
1571 	udc->write_fn(udc->addr, ep0->offset, epcfgreg);
1572 }
1573 
1574 /**
1575  * xudc_setaddress - executes SET_ADDRESS command
1576  * @udc: pointer to the udc structure.
1577  *
1578  * This function executes USB SET_ADDRESS command
1579  */
1580 static void xudc_setaddress(struct xusb_udc *udc)
1581 {
1582 	struct xusb_ep *ep0	= &udc->ep[0];
1583 	struct xusb_req *req	= udc->req;
1584 	int ret;
1585 
1586 	req->usb_req.length = 0;
1587 	ret = __xudc_ep0_queue(ep0, req);
1588 	if (ret == 0)
1589 		return;
1590 
1591 	dev_err(udc->dev, "Can't respond to SET ADDRESS request\n");
1592 	xudc_ep0_stall(udc);
1593 }
1594 
1595 /**
1596  * xudc_getstatus - executes GET_STATUS command
1597  * @udc: pointer to the udc structure.
1598  *
1599  * This function executes USB GET_STATUS command
1600  */
1601 static void xudc_getstatus(struct xusb_udc *udc)
1602 {
1603 	struct xusb_ep *ep0	= &udc->ep[0];
1604 	struct xusb_req *req	= udc->req;
1605 	struct xusb_ep *target_ep;
1606 	u16 status = 0;
1607 	u32 epcfgreg;
1608 	int epnum;
1609 	u32 halt;
1610 	int ret;
1611 
1612 	switch (udc->setup.bRequestType & USB_RECIP_MASK) {
1613 	case USB_RECIP_DEVICE:
1614 		/* Get device status */
1615 		status = 1 << USB_DEVICE_SELF_POWERED;
1616 		if (udc->remote_wkp)
1617 			status |= (1 << USB_DEVICE_REMOTE_WAKEUP);
1618 		break;
1619 	case USB_RECIP_INTERFACE:
1620 		break;
1621 	case USB_RECIP_ENDPOINT:
1622 		epnum = le16_to_cpu(udc->setup.wIndex) & USB_ENDPOINT_NUMBER_MASK;
1623 		if (epnum >= XUSB_MAX_ENDPOINTS)
1624 			goto stall;
1625 		target_ep = &udc->ep[epnum];
1626 		epcfgreg = udc->read_fn(udc->addr + target_ep->offset);
1627 		halt = epcfgreg & XUSB_EP_CFG_STALL_MASK;
1628 		if (le16_to_cpu(udc->setup.wIndex) & USB_DIR_IN) {
1629 			if (!target_ep->is_in)
1630 				goto stall;
1631 		} else {
1632 			if (target_ep->is_in)
1633 				goto stall;
1634 		}
1635 		if (halt)
1636 			status = 1 << USB_ENDPOINT_HALT;
1637 		break;
1638 	default:
1639 		goto stall;
1640 	}
1641 
1642 	req->usb_req.length = 2;
1643 	*(__le16 *)req->usb_req.buf = cpu_to_le16(status);
1644 	ret = __xudc_ep0_queue(ep0, req);
1645 	if (ret == 0)
1646 		return;
1647 stall:
1648 	dev_err(udc->dev, "Can't respond to getstatus request\n");
1649 	xudc_ep0_stall(udc);
1650 }
1651 
1652 /**
1653  * xudc_set_clear_feature - Executes the set feature and clear feature commands.
1654  * @udc: pointer to the usb device controller structure.
1655  *
1656  * Processes the SET_FEATURE and CLEAR_FEATURE commands.
1657  */
1658 static void xudc_set_clear_feature(struct xusb_udc *udc)
1659 {
1660 	struct xusb_ep *ep0	= &udc->ep[0];
1661 	struct xusb_req *req	= udc->req;
1662 	struct xusb_ep *target_ep;
1663 	u8 endpoint;
1664 	u8 outinbit;
1665 	u32 epcfgreg;
1666 	int flag = (udc->setup.bRequest == USB_REQ_SET_FEATURE ? 1 : 0);
1667 	int ret;
1668 
1669 	switch (udc->setup.bRequestType) {
1670 	case USB_RECIP_DEVICE:
1671 		switch (le16_to_cpu(udc->setup.wValue)) {
1672 		case USB_DEVICE_TEST_MODE:
1673 			/*
1674 			 * The Test Mode will be executed
1675 			 * after the status phase.
1676 			 */
1677 			break;
1678 		case USB_DEVICE_REMOTE_WAKEUP:
1679 			if (flag)
1680 				udc->remote_wkp = 1;
1681 			else
1682 				udc->remote_wkp = 0;
1683 			break;
1684 		default:
1685 			xudc_ep0_stall(udc);
1686 			break;
1687 		}
1688 		break;
1689 	case USB_RECIP_ENDPOINT:
1690 		if (!udc->setup.wValue) {
1691 			endpoint = le16_to_cpu(udc->setup.wIndex) &
1692 					       USB_ENDPOINT_NUMBER_MASK;
1693 			if (endpoint >= XUSB_MAX_ENDPOINTS) {
1694 				xudc_ep0_stall(udc);
1695 				return;
1696 			}
1697 			target_ep = &udc->ep[endpoint];
1698 			outinbit = le16_to_cpu(udc->setup.wIndex) &
1699 					       USB_ENDPOINT_DIR_MASK;
1700 			outinbit = outinbit >> 7;
1701 
1702 			/* Make sure direction matches.*/
1703 			if (outinbit != target_ep->is_in) {
1704 				xudc_ep0_stall(udc);
1705 				return;
1706 			}
1707 			epcfgreg = udc->read_fn(udc->addr + target_ep->offset);
1708 			if (!endpoint) {
1709 				/* Clear the stall.*/
1710 				epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
1711 				udc->write_fn(udc->addr,
1712 					      target_ep->offset, epcfgreg);
1713 			} else {
1714 				if (flag) {
1715 					epcfgreg |= XUSB_EP_CFG_STALL_MASK;
1716 					udc->write_fn(udc->addr,
1717 						      target_ep->offset,
1718 						      epcfgreg);
1719 				} else {
1720 					/* Unstall the endpoint.*/
1721 					epcfgreg &= ~(XUSB_EP_CFG_STALL_MASK |
1722 						XUSB_EP_CFG_DATA_TOGGLE_MASK);
1723 					udc->write_fn(udc->addr,
1724 						      target_ep->offset,
1725 						      epcfgreg);
1726 				}
1727 			}
1728 		}
1729 		break;
1730 	default:
1731 		xudc_ep0_stall(udc);
1732 		return;
1733 	}
1734 
1735 	req->usb_req.length = 0;
1736 	ret = __xudc_ep0_queue(ep0, req);
1737 	if (ret == 0)
1738 		return;
1739 
1740 	dev_err(udc->dev, "Can't respond to SET/CLEAR FEATURE\n");
1741 	xudc_ep0_stall(udc);
1742 }
1743 
1744 /**
1745  * xudc_handle_setup - Processes the setup packet.
1746  * @udc: pointer to the usb device controller structure.
1747  *
1748  * Process setup packet and delegate to gadget layer.
1749  */
1750 static void xudc_handle_setup(struct xusb_udc *udc)
1751 	__must_hold(&udc->lock)
1752 {
1753 	struct xusb_ep *ep0 = &udc->ep[0];
1754 	struct usb_ctrlrequest setup;
1755 	u32 *ep0rambase;
1756 
1757 	/* Load up the chapter 9 command buffer.*/
1758 	ep0rambase = (u32 __force *) (udc->addr + XUSB_SETUP_PKT_ADDR_OFFSET);
1759 	memcpy_toio((void __iomem *)&setup, ep0rambase, 8);
1760 
1761 	udc->setup = setup;
1762 	udc->setup.wValue = cpu_to_le16((u16 __force)setup.wValue);
1763 	udc->setup.wIndex = cpu_to_le16((u16 __force)setup.wIndex);
1764 	udc->setup.wLength = cpu_to_le16((u16 __force)setup.wLength);
1765 
1766 	/* Clear previous requests */
1767 	xudc_nuke(ep0, -ECONNRESET);
1768 
1769 	if (udc->setup.bRequestType & USB_DIR_IN) {
1770 		/* Execute the get command.*/
1771 		udc->setupseqrx = STATUS_PHASE;
1772 		udc->setupseqtx = DATA_PHASE;
1773 	} else {
1774 		/* Execute the put command.*/
1775 		udc->setupseqrx = DATA_PHASE;
1776 		udc->setupseqtx = STATUS_PHASE;
1777 	}
1778 
1779 	switch (udc->setup.bRequest) {
1780 	case USB_REQ_GET_STATUS:
1781 		/* Data+Status phase form udc */
1782 		if ((udc->setup.bRequestType &
1783 				(USB_DIR_IN | USB_TYPE_MASK)) !=
1784 				(USB_DIR_IN | USB_TYPE_STANDARD))
1785 			break;
1786 		xudc_getstatus(udc);
1787 		return;
1788 	case USB_REQ_SET_ADDRESS:
1789 		/* Status phase from udc */
1790 		if (udc->setup.bRequestType != (USB_DIR_OUT |
1791 				USB_TYPE_STANDARD | USB_RECIP_DEVICE))
1792 			break;
1793 		xudc_setaddress(udc);
1794 		return;
1795 	case USB_REQ_CLEAR_FEATURE:
1796 	case USB_REQ_SET_FEATURE:
1797 		/* Requests with no data phase, status phase from udc */
1798 		if ((udc->setup.bRequestType & USB_TYPE_MASK)
1799 				!= USB_TYPE_STANDARD)
1800 			break;
1801 		xudc_set_clear_feature(udc);
1802 		return;
1803 	default:
1804 		break;
1805 	}
1806 
1807 	spin_unlock(&udc->lock);
1808 	if (udc->driver->setup(&udc->gadget, &setup) < 0)
1809 		xudc_ep0_stall(udc);
1810 	spin_lock(&udc->lock);
1811 }
1812 
1813 /**
1814  * xudc_ep0_out - Processes the endpoint 0 OUT token.
1815  * @udc: pointer to the usb device controller structure.
1816  */
1817 static void xudc_ep0_out(struct xusb_udc *udc)
1818 {
1819 	struct xusb_ep *ep0 = &udc->ep[0];
1820 	struct xusb_req *req;
1821 	u8 *ep0rambase;
1822 	unsigned int bytes_to_rx;
1823 	void *buffer;
1824 
1825 	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
1826 
1827 	switch (udc->setupseqrx) {
1828 	case STATUS_PHASE:
1829 		/*
1830 		 * This resets both state machines for the next
1831 		 * Setup packet.
1832 		 */
1833 		udc->setupseqrx = SETUP_PHASE;
1834 		udc->setupseqtx = SETUP_PHASE;
1835 		req->usb_req.actual = req->usb_req.length;
1836 		xudc_done(ep0, req, 0);
1837 		break;
1838 	case DATA_PHASE:
1839 		bytes_to_rx = udc->read_fn(udc->addr +
1840 					   XUSB_EP_BUF0COUNT_OFFSET);
1841 		/* Copy the data to be received from the DPRAM. */
1842 		ep0rambase = (u8 __force *) (udc->addr +
1843 			     (ep0->rambase << 2));
1844 		buffer = req->usb_req.buf + req->usb_req.actual;
1845 		req->usb_req.actual = req->usb_req.actual + bytes_to_rx;
1846 		memcpy_toio((void __iomem *)buffer, ep0rambase, bytes_to_rx);
1847 
1848 		if (req->usb_req.length == req->usb_req.actual) {
1849 			/* Data transfer completed get ready for Status stage */
1850 			xudc_wrstatus(udc);
1851 		} else {
1852 			/* Enable EP0 buffer to receive data */
1853 			udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, 0);
1854 			udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1855 		}
1856 		break;
1857 	default:
1858 		break;
1859 	}
1860 }
1861 
1862 /**
1863  * xudc_ep0_in - Processes the endpoint 0 IN token.
1864  * @udc: pointer to the usb device controller structure.
1865  */
1866 static void xudc_ep0_in(struct xusb_udc *udc)
1867 {
1868 	struct xusb_ep *ep0 = &udc->ep[0];
1869 	struct xusb_req *req;
1870 	unsigned int bytes_to_tx;
1871 	void *buffer;
1872 	u32 epcfgreg;
1873 	u16 count = 0;
1874 	u16 length;
1875 	u8 *ep0rambase;
1876 	u8 test_mode = le16_to_cpu(udc->setup.wIndex) >> 8;
1877 
1878 	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
1879 	bytes_to_tx = req->usb_req.length - req->usb_req.actual;
1880 
1881 	switch (udc->setupseqtx) {
1882 	case STATUS_PHASE:
1883 		switch (udc->setup.bRequest) {
1884 		case USB_REQ_SET_ADDRESS:
1885 			/* Set the address of the device.*/
1886 			udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET,
1887 				      le16_to_cpu(udc->setup.wValue));
1888 			break;
1889 		case USB_REQ_SET_FEATURE:
1890 			if (udc->setup.bRequestType ==
1891 					USB_RECIP_DEVICE) {
1892 				if (le16_to_cpu(udc->setup.wValue) ==
1893 						USB_DEVICE_TEST_MODE)
1894 					udc->write_fn(udc->addr,
1895 						      XUSB_TESTMODE_OFFSET,
1896 						      test_mode);
1897 			}
1898 			break;
1899 		}
1900 		req->usb_req.actual = req->usb_req.length;
1901 		xudc_done(ep0, req, 0);
1902 		break;
1903 	case DATA_PHASE:
1904 		if (!bytes_to_tx) {
1905 			/*
1906 			 * We're done with data transfer, next
1907 			 * will be zero length OUT with data toggle of
1908 			 * 1. Setup data_toggle.
1909 			 */
1910 			epcfgreg = udc->read_fn(udc->addr + ep0->offset);
1911 			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
1912 			udc->write_fn(udc->addr, ep0->offset, epcfgreg);
1913 			udc->setupseqtx = STATUS_PHASE;
1914 		} else {
1915 			length = count = min_t(u32, bytes_to_tx,
1916 					       EP0_MAX_PACKET);
1917 			/* Copy the data to be transmitted into the DPRAM. */
1918 			ep0rambase = (u8 __force *) (udc->addr +
1919 				     (ep0->rambase << 2));
1920 			buffer = req->usb_req.buf + req->usb_req.actual;
1921 			req->usb_req.actual = req->usb_req.actual + length;
1922 			memcpy_toio((void __iomem *)ep0rambase, buffer, length);
1923 		}
1924 		udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, count);
1925 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1926 		break;
1927 	default:
1928 		break;
1929 	}
1930 }
1931 
1932 /**
1933  * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
1934  * @udc: pointer to the udc structure.
1935  * @intrstatus:	It's the mask value for the interrupt sources on endpoint 0.
1936  *
1937  * Processes the commands received during enumeration phase.
1938  */
1939 static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
1940 {
1941 
1942 	if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
1943 		xudc_handle_setup(udc);
1944 	} else {
1945 		if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
1946 			xudc_ep0_out(udc);
1947 		else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
1948 			xudc_ep0_in(udc);
1949 	}
1950 }
1951 
1952 /**
1953  * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
1954  * @udc: pointer to the udc structure.
1955  * @epnum: End point number for which the interrupt is to be processed
1956  * @intrstatus:	mask value for interrupt sources of endpoints other
1957  *		than endpoint 0.
1958  *
1959  * Processes the buffer completion interrupts.
1960  */
1961 static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
1962 				    u32 intrstatus)
1963 {
1964 
1965 	struct xusb_req *req;
1966 	struct xusb_ep *ep;
1967 
1968 	ep = &udc->ep[epnum];
1969 	/* Process the End point interrupts.*/
1970 	if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
1971 		ep->buffer0ready = 0;
1972 	if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
1973 		ep->buffer1ready = false;
1974 
1975 	if (list_empty(&ep->queue))
1976 		return;
1977 
1978 	req = list_first_entry(&ep->queue, struct xusb_req, queue);
1979 
1980 	if (ep->is_in)
1981 		xudc_write_fifo(ep, req);
1982 	else
1983 		xudc_read_fifo(ep, req);
1984 }
1985 
1986 /**
1987  * xudc_irq - The main interrupt handler.
1988  * @irq: The interrupt number.
1989  * @_udc: pointer to the usb device controller structure.
1990  *
1991  * Return: IRQ_HANDLED after the interrupt is handled.
1992  */
1993 static irqreturn_t xudc_irq(int irq, void *_udc)
1994 {
1995 	struct xusb_udc *udc = _udc;
1996 	u32 intrstatus;
1997 	u32 ier;
1998 	u8 index;
1999 	u32 bufintr;
2000 	unsigned long flags;
2001 
2002 	spin_lock_irqsave(&udc->lock, flags);
2003 
2004 	/*
2005 	 * Event interrupts are level sensitive hence first disable
2006 	 * IER, read ISR and figure out active interrupts.
2007 	 */
2008 	ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
2009 	ier &= ~XUSB_STATUS_INTR_EVENT_MASK;
2010 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
2011 
2012 	/* Read the Interrupt Status Register.*/
2013 	intrstatus = udc->read_fn(udc->addr + XUSB_STATUS_OFFSET);
2014 
2015 	/* Call the handler for the event interrupt.*/
2016 	if (intrstatus & XUSB_STATUS_INTR_EVENT_MASK) {
2017 		/*
2018 		 * Check if there is any action to be done for :
2019 		 * - USB Reset received {XUSB_STATUS_RESET_MASK}
2020 		 * - USB Suspend received {XUSB_STATUS_SUSPEND_MASK}
2021 		 * - USB Resume received {XUSB_STATUS_RESUME_MASK}
2022 		 * - USB Disconnect received {XUSB_STATUS_DISCONNECT_MASK}
2023 		 */
2024 		xudc_startup_handler(udc, intrstatus);
2025 	}
2026 
2027 	/* Check the buffer completion interrupts */
2028 	if (intrstatus & XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK) {
2029 		/* Enable Reset, Suspend, Resume and Disconnect  */
2030 		ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
2031 		ier |= XUSB_STATUS_INTR_EVENT_MASK;
2032 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
2033 
2034 		if (intrstatus & XUSB_STATUS_EP0_BUFF1_COMP_MASK)
2035 			xudc_ctrl_ep_handler(udc, intrstatus);
2036 
2037 		for (index = 1; index < 8; index++) {
2038 			bufintr = ((intrstatus &
2039 				  (XUSB_STATUS_EP1_BUFF1_COMP_MASK <<
2040 				  (index - 1))) || (intrstatus &
2041 				  (XUSB_STATUS_EP1_BUFF2_COMP_MASK <<
2042 				  (index - 1))));
2043 			if (bufintr) {
2044 				xudc_nonctrl_ep_handler(udc, index,
2045 							intrstatus);
2046 			}
2047 		}
2048 	}
2049 
2050 	spin_unlock_irqrestore(&udc->lock, flags);
2051 	return IRQ_HANDLED;
2052 }
2053 
2054 /**
2055  * xudc_probe - The device probe function for driver initialization.
2056  * @pdev: pointer to the platform device structure.
2057  *
2058  * Return: 0 for success and error value on failure
2059  */
2060 static int xudc_probe(struct platform_device *pdev)
2061 {
2062 	struct device_node *np = pdev->dev.of_node;
2063 	struct resource *res;
2064 	struct xusb_udc *udc;
2065 	int irq;
2066 	int ret;
2067 	u32 ier;
2068 	u8 *buff;
2069 
2070 	udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
2071 	if (!udc)
2072 		return -ENOMEM;
2073 
2074 	/* Create a dummy request for GET_STATUS, SET_ADDRESS */
2075 	udc->req = devm_kzalloc(&pdev->dev, sizeof(struct xusb_req),
2076 				GFP_KERNEL);
2077 	if (!udc->req)
2078 		return -ENOMEM;
2079 
2080 	buff = devm_kzalloc(&pdev->dev, STATUSBUFF_SIZE, GFP_KERNEL);
2081 	if (!buff)
2082 		return -ENOMEM;
2083 
2084 	udc->req->usb_req.buf = buff;
2085 
2086 	/* Map the registers */
2087 	udc->addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
2088 	if (IS_ERR(udc->addr))
2089 		return PTR_ERR(udc->addr);
2090 
2091 	irq = platform_get_irq(pdev, 0);
2092 	if (irq < 0)
2093 		return irq;
2094 	ret = devm_request_irq(&pdev->dev, irq, xudc_irq, 0,
2095 			       dev_name(&pdev->dev), udc);
2096 	if (ret < 0) {
2097 		dev_dbg(&pdev->dev, "unable to request irq %d", irq);
2098 		goto fail;
2099 	}
2100 
2101 	udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");
2102 
2103 	/* Setup gadget structure */
2104 	udc->gadget.ops = &xusb_udc_ops;
2105 	udc->gadget.max_speed = USB_SPEED_HIGH;
2106 	udc->gadget.speed = USB_SPEED_UNKNOWN;
2107 	udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
2108 	udc->gadget.name = driver_name;
2109 
2110 	udc->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
2111 	if (IS_ERR(udc->clk)) {
2112 		if (PTR_ERR(udc->clk) != -ENOENT) {
2113 			ret = PTR_ERR(udc->clk);
2114 			goto fail;
2115 		}
2116 
2117 		/*
2118 		 * Clock framework support is optional, continue on,
2119 		 * anyways if we don't find a matching clock
2120 		 */
2121 		dev_warn(&pdev->dev, "s_axi_aclk clock property is not found\n");
2122 		udc->clk = NULL;
2123 	}
2124 
2125 	ret = clk_prepare_enable(udc->clk);
2126 	if (ret) {
2127 		dev_err(&pdev->dev, "Unable to enable clock.\n");
2128 		return ret;
2129 	}
2130 
2131 	spin_lock_init(&udc->lock);
2132 
2133 	/* Check for IP endianness */
2134 	udc->write_fn = xudc_write32_be;
2135 	udc->read_fn = xudc_read32_be;
2136 	udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, USB_TEST_J);
2137 	if ((udc->read_fn(udc->addr + XUSB_TESTMODE_OFFSET))
2138 			!= USB_TEST_J) {
2139 		udc->write_fn = xudc_write32;
2140 		udc->read_fn = xudc_read32;
2141 	}
2142 	udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, 0);
2143 
2144 	xudc_eps_init(udc);
2145 
2146 	/* Set device address to 0.*/
2147 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
2148 
2149 	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
2150 	if (ret)
2151 		goto err_disable_unprepare_clk;
2152 
2153 	udc->dev = &udc->gadget.dev;
2154 
2155 	/* Enable the interrupts.*/
2156 	ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
2157 	      XUSB_STATUS_FIFO_BUFF_RDY_MASK | XUSB_STATUS_FIFO_BUFF_FREE_MASK |
2158 	      XUSB_STATUS_SETUP_PACKET_MASK |
2159 	      XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
2160 
2161 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
2162 
2163 	platform_set_drvdata(pdev, udc);
2164 
2165 	dev_vdbg(&pdev->dev, "%s at 0x%08X mapped to %p %s\n",
2166 		 driver_name, (u32)res->start, udc->addr,
2167 		 udc->dma_enabled ? "with DMA" : "without DMA");
2168 
2169 	return 0;
2170 
2171 err_disable_unprepare_clk:
2172 	clk_disable_unprepare(udc->clk);
2173 fail:
2174 	dev_err(&pdev->dev, "probe failed, %d\n", ret);
2175 	return ret;
2176 }
2177 
2178 /**
2179  * xudc_remove - Releases the resources allocated during the initialization.
2180  * @pdev: pointer to the platform device structure.
2181  *
2182  * Return: 0 always
2183  */
2184 static void xudc_remove(struct platform_device *pdev)
2185 {
2186 	struct xusb_udc *udc = platform_get_drvdata(pdev);
2187 
2188 	usb_del_gadget_udc(&udc->gadget);
2189 	clk_disable_unprepare(udc->clk);
2190 }
2191 
2192 #ifdef CONFIG_PM_SLEEP
2193 static int xudc_suspend(struct device *dev)
2194 {
2195 	struct xusb_udc *udc;
2196 	u32 crtlreg;
2197 	unsigned long flags;
2198 
2199 	udc = dev_get_drvdata(dev);
2200 
2201 	spin_lock_irqsave(&udc->lock, flags);
2202 
2203 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
2204 	crtlreg &= ~XUSB_CONTROL_USB_READY_MASK;
2205 
2206 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
2207 
2208 	spin_unlock_irqrestore(&udc->lock, flags);
2209 	if (udc->driver && udc->driver->suspend)
2210 		udc->driver->suspend(&udc->gadget);
2211 
2212 	clk_disable(udc->clk);
2213 
2214 	return 0;
2215 }
2216 
2217 static int xudc_resume(struct device *dev)
2218 {
2219 	struct xusb_udc *udc;
2220 	u32 crtlreg;
2221 	unsigned long flags;
2222 	int ret;
2223 
2224 	udc = dev_get_drvdata(dev);
2225 
2226 	ret = clk_enable(udc->clk);
2227 	if (ret < 0)
2228 		return ret;
2229 
2230 	spin_lock_irqsave(&udc->lock, flags);
2231 
2232 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
2233 	crtlreg |= XUSB_CONTROL_USB_READY_MASK;
2234 
2235 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
2236 
2237 	spin_unlock_irqrestore(&udc->lock, flags);
2238 
2239 	return 0;
2240 }
2241 #endif /* CONFIG_PM_SLEEP */
2242 
2243 static const struct dev_pm_ops xudc_pm_ops = {
2244 	SET_SYSTEM_SLEEP_PM_OPS(xudc_suspend, xudc_resume)
2245 };
2246 
2247 /* Match table for of_platform binding */
2248 static const struct of_device_id usb_of_match[] = {
2249 	{ .compatible = "xlnx,usb2-device-4.00.a", },
2250 	{ /* end of list */ },
2251 };
2252 MODULE_DEVICE_TABLE(of, usb_of_match);
2253 
2254 static struct platform_driver xudc_driver = {
2255 	.driver = {
2256 		.name = driver_name,
2257 		.of_match_table = usb_of_match,
2258 		.pm	= &xudc_pm_ops,
2259 	},
2260 	.probe = xudc_probe,
2261 	.remove_new = xudc_remove,
2262 };
2263 
2264 module_platform_driver(xudc_driver);
2265 
2266 MODULE_DESCRIPTION("Xilinx udc driver");
2267 MODULE_AUTHOR("Xilinx, Inc");
2268 MODULE_LICENSE("GPL");
2269