xref: /linux/drivers/tty/serial/8250/8250_exar.c (revision 1e525507)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Probe module for 8250/16550-type Exar chips PCI serial ports.
4  *
5  *  Based on drivers/tty/serial/8250/8250_pci.c,
6  *
7  *  Copyright (C) 2017 Sudip Mukherjee, All Rights Reserved.
8  */
9 #include <linux/bits.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/dmi.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/math.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm.h>
20 #include <linux/property.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 
24 #include <linux/serial_8250.h>
25 #include <linux/serial_core.h>
26 #include <linux/serial_reg.h>
27 
28 #include <asm/byteorder.h>
29 
30 #include "8250.h"
31 #include "8250_pcilib.h"
32 
33 #define PCI_DEVICE_ID_ACCESSIO_COM_2S		0x1052
34 #define PCI_DEVICE_ID_ACCESSIO_COM_4S		0x105d
35 #define PCI_DEVICE_ID_ACCESSIO_COM_8S		0x106c
36 #define PCI_DEVICE_ID_ACCESSIO_COM232_8		0x10a8
37 #define PCI_DEVICE_ID_ACCESSIO_COM_2SM		0x10d2
38 #define PCI_DEVICE_ID_ACCESSIO_COM_4SM		0x10db
39 #define PCI_DEVICE_ID_ACCESSIO_COM_8SM		0x10ea
40 
41 #define PCI_DEVICE_ID_COMMTECH_4224PCI335	0x0002
42 #define PCI_DEVICE_ID_COMMTECH_4222PCI335	0x0004
43 #define PCI_DEVICE_ID_COMMTECH_2324PCI335	0x000a
44 #define PCI_DEVICE_ID_COMMTECH_2328PCI335	0x000b
45 #define PCI_DEVICE_ID_COMMTECH_4224PCIE		0x0020
46 #define PCI_DEVICE_ID_COMMTECH_4228PCIE		0x0021
47 #define PCI_DEVICE_ID_COMMTECH_4222PCIE		0x0022
48 
49 #define PCI_DEVICE_ID_EXAR_XR17V4358		0x4358
50 #define PCI_DEVICE_ID_EXAR_XR17V8358		0x8358
51 
52 #define PCI_SUBDEVICE_ID_USR_2980		0x0128
53 #define PCI_SUBDEVICE_ID_USR_2981		0x0129
54 
55 #define UART_EXAR_INT0		0x80
56 #define UART_EXAR_8XMODE	0x88	/* 8X sampling rate select */
57 #define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
58 #define UART_EXAR_DVID		0x8d	/* Device identification */
59 
60 #define UART_EXAR_FCTR		0x08	/* Feature Control Register */
61 #define UART_FCTR_EXAR_IRDA	0x10	/* IrDa data encode select */
62 #define UART_FCTR_EXAR_485	0x20	/* Auto 485 half duplex dir ctl */
63 #define UART_FCTR_EXAR_TRGA	0x00	/* FIFO trigger table A */
64 #define UART_FCTR_EXAR_TRGB	0x60	/* FIFO trigger table B */
65 #define UART_FCTR_EXAR_TRGC	0x80	/* FIFO trigger table C */
66 #define UART_FCTR_EXAR_TRGD	0xc0	/* FIFO trigger table D programmable */
67 
68 #define UART_EXAR_TXTRG		0x0a	/* Tx FIFO trigger level write-only */
69 #define UART_EXAR_RXTRG		0x0b	/* Rx FIFO trigger level write-only */
70 
71 #define UART_EXAR_MPIOINT_7_0	0x8f	/* MPIOINT[7:0] */
72 #define UART_EXAR_MPIOLVL_7_0	0x90	/* MPIOLVL[7:0] */
73 #define UART_EXAR_MPIO3T_7_0	0x91	/* MPIO3T[7:0] */
74 #define UART_EXAR_MPIOINV_7_0	0x92	/* MPIOINV[7:0] */
75 #define UART_EXAR_MPIOSEL_7_0	0x93	/* MPIOSEL[7:0] */
76 #define UART_EXAR_MPIOOD_7_0	0x94	/* MPIOOD[7:0] */
77 #define UART_EXAR_MPIOINT_15_8	0x95	/* MPIOINT[15:8] */
78 #define UART_EXAR_MPIOLVL_15_8	0x96	/* MPIOLVL[15:8] */
79 #define UART_EXAR_MPIO3T_15_8	0x97	/* MPIO3T[15:8] */
80 #define UART_EXAR_MPIOINV_15_8	0x98	/* MPIOINV[15:8] */
81 #define UART_EXAR_MPIOSEL_15_8	0x99	/* MPIOSEL[15:8] */
82 #define UART_EXAR_MPIOOD_15_8	0x9a	/* MPIOOD[15:8] */
83 
84 #define UART_EXAR_RS485_DLY(x)	((x) << 4)
85 
86 #define UART_EXAR_DLD			0x02 /* Divisor Fractional */
87 #define UART_EXAR_DLD_485_POLARITY	0x80 /* RS-485 Enable Signal Polarity */
88 
89 /*
90  * IOT2040 MPIO wiring semantics:
91  *
92  * MPIO		Port	Function
93  * ----		----	--------
94  * 0		2 	Mode bit 0
95  * 1		2	Mode bit 1
96  * 2		2	Terminate bus
97  * 3		-	<reserved>
98  * 4		3	Mode bit 0
99  * 5		3	Mode bit 1
100  * 6		3	Terminate bus
101  * 7		-	<reserved>
102  * 8		2	Enable
103  * 9		3	Enable
104  * 10		-	Red LED
105  * 11..15	-	<unused>
106  */
107 
108 /* IOT2040 MPIOs 0..7 */
109 #define IOT2040_UART_MODE_RS232		0x01
110 #define IOT2040_UART_MODE_RS485		0x02
111 #define IOT2040_UART_MODE_RS422		0x03
112 #define IOT2040_UART_TERMINATE_BUS	0x04
113 
114 #define IOT2040_UART1_MASK		0x0f
115 #define IOT2040_UART2_SHIFT		4
116 
117 #define IOT2040_UARTS_DEFAULT_MODE	0x11	/* both RS232 */
118 #define IOT2040_UARTS_GPIO_LO_MODE	0x88	/* reserved pins as input */
119 
120 /* IOT2040 MPIOs 8..15 */
121 #define IOT2040_UARTS_ENABLE		0x03
122 #define IOT2040_UARTS_GPIO_HI_MODE	0xF8	/* enable & LED as outputs */
123 
124 struct exar8250;
125 
126 struct exar8250_platform {
127 	int (*rs485_config)(struct uart_port *port, struct ktermios *termios,
128 			    struct serial_rs485 *rs485);
129 	const struct serial_rs485 *rs485_supported;
130 	int (*register_gpio)(struct pci_dev *, struct uart_8250_port *);
131 	void (*unregister_gpio)(struct uart_8250_port *);
132 };
133 
134 /**
135  * struct exar8250_board - board information
136  * @num_ports: number of serial ports
137  * @reg_shift: describes UART register mapping in PCI memory
138  * @setup: quirk run at ->probe() stage
139  * @exit: quirk run at ->remove() stage
140  */
141 struct exar8250_board {
142 	unsigned int num_ports;
143 	unsigned int reg_shift;
144 	int	(*setup)(struct exar8250 *, struct pci_dev *,
145 			 struct uart_8250_port *, int);
146 	void	(*exit)(struct pci_dev *pcidev);
147 };
148 
149 struct exar8250 {
150 	unsigned int		nr;
151 	struct exar8250_board	*board;
152 	void __iomem		*virt;
153 	int			line[];
154 };
155 
156 static void exar_pm(struct uart_port *port, unsigned int state, unsigned int old)
157 {
158 	/*
159 	 * Exar UARTs have a SLEEP register that enables or disables each UART
160 	 * to enter sleep mode separately. On the XR17V35x the register
161 	 * is accessible to each UART at the UART_EXAR_SLEEP offset, but
162 	 * the UART channel may only write to the corresponding bit.
163 	 */
164 	serial_port_out(port, UART_EXAR_SLEEP, state ? 0xff : 0);
165 }
166 
167 /*
168  * XR17V35x UARTs have an extra fractional divisor register (DLD)
169  * Calculate divisor with extra 4-bit fractional portion
170  */
171 static unsigned int xr17v35x_get_divisor(struct uart_port *p, unsigned int baud,
172 					 unsigned int *frac)
173 {
174 	unsigned int quot_16;
175 
176 	quot_16 = DIV_ROUND_CLOSEST(p->uartclk, baud);
177 	*frac = quot_16 & 0x0f;
178 
179 	return quot_16 >> 4;
180 }
181 
182 static void xr17v35x_set_divisor(struct uart_port *p, unsigned int baud,
183 				 unsigned int quot, unsigned int quot_frac)
184 {
185 	serial8250_do_set_divisor(p, baud, quot, quot_frac);
186 
187 	/* Preserve bits not related to baudrate; DLD[7:4]. */
188 	quot_frac |= serial_port_in(p, 0x2) & 0xf0;
189 	serial_port_out(p, 0x2, quot_frac);
190 }
191 
192 static int xr17v35x_startup(struct uart_port *port)
193 {
194 	/*
195 	 * First enable access to IER [7:5], ISR [5:4], FCR [5:4],
196 	 * MCR [7:5] and MSR [7:0]
197 	 */
198 	serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);
199 
200 	/*
201 	 * Make sure all interrups are masked until initialization is
202 	 * complete and the FIFOs are cleared
203 	 *
204 	 * Synchronize UART_IER access against the console.
205 	 */
206 	uart_port_lock_irq(port);
207 	serial_port_out(port, UART_IER, 0);
208 	uart_port_unlock_irq(port);
209 
210 	return serial8250_do_startup(port);
211 }
212 
213 static void exar_shutdown(struct uart_port *port)
214 {
215 	bool tx_complete = false;
216 	struct uart_8250_port *up = up_to_u8250p(port);
217 	struct circ_buf *xmit = &port->state->xmit;
218 	int i = 0;
219 	u16 lsr;
220 
221 	do {
222 		lsr = serial_in(up, UART_LSR);
223 		if (lsr & (UART_LSR_TEMT | UART_LSR_THRE))
224 			tx_complete = true;
225 		else
226 			tx_complete = false;
227 		usleep_range(1000, 1100);
228 	} while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000);
229 
230 	serial8250_do_shutdown(port);
231 }
232 
233 static int default_setup(struct exar8250 *priv, struct pci_dev *pcidev,
234 			 int idx, unsigned int offset,
235 			 struct uart_8250_port *port)
236 {
237 	const struct exar8250_board *board = priv->board;
238 	unsigned char status;
239 	int err;
240 
241 	err = serial8250_pci_setup_port(pcidev, port, 0, offset, board->reg_shift);
242 	if (err)
243 		return err;
244 
245 	/*
246 	 * XR17V35x UARTs have an extra divisor register, DLD that gets enabled
247 	 * with when DLAB is set which will cause the device to incorrectly match
248 	 * and assign port type to PORT_16650. The EFR for this UART is found
249 	 * at offset 0x09. Instead check the Deice ID (DVID) register
250 	 * for a 2, 4 or 8 port UART.
251 	 */
252 	status = readb(port->port.membase + UART_EXAR_DVID);
253 	if (status == 0x82 || status == 0x84 || status == 0x88) {
254 		port->port.type = PORT_XR17V35X;
255 
256 		port->port.get_divisor = xr17v35x_get_divisor;
257 		port->port.set_divisor = xr17v35x_set_divisor;
258 
259 		port->port.startup = xr17v35x_startup;
260 	} else {
261 		port->port.type = PORT_XR17D15X;
262 	}
263 
264 	port->port.pm = exar_pm;
265 	port->port.shutdown = exar_shutdown;
266 
267 	return 0;
268 }
269 
270 static int
271 pci_fastcom335_setup(struct exar8250 *priv, struct pci_dev *pcidev,
272 		     struct uart_8250_port *port, int idx)
273 {
274 	unsigned int offset = idx * 0x200;
275 	unsigned int baud = 1843200;
276 	u8 __iomem *p;
277 	int err;
278 
279 	port->port.uartclk = baud * 16;
280 
281 	err = default_setup(priv, pcidev, idx, offset, port);
282 	if (err)
283 		return err;
284 
285 	p = port->port.membase;
286 
287 	writeb(0x00, p + UART_EXAR_8XMODE);
288 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
289 	writeb(32, p + UART_EXAR_TXTRG);
290 	writeb(32, p + UART_EXAR_RXTRG);
291 
292 	/*
293 	 * Setup Multipurpose Input/Output pins.
294 	 */
295 	if (idx == 0) {
296 		switch (pcidev->device) {
297 		case PCI_DEVICE_ID_COMMTECH_4222PCI335:
298 		case PCI_DEVICE_ID_COMMTECH_4224PCI335:
299 			writeb(0x78, p + UART_EXAR_MPIOLVL_7_0);
300 			writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
301 			writeb(0x00, p + UART_EXAR_MPIOSEL_7_0);
302 			break;
303 		case PCI_DEVICE_ID_COMMTECH_2324PCI335:
304 		case PCI_DEVICE_ID_COMMTECH_2328PCI335:
305 			writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
306 			writeb(0xc0, p + UART_EXAR_MPIOINV_7_0);
307 			writeb(0xc0, p + UART_EXAR_MPIOSEL_7_0);
308 			break;
309 		}
310 		writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
311 		writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
312 		writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
313 	}
314 
315 	return 0;
316 }
317 
318 static int
319 pci_connect_tech_setup(struct exar8250 *priv, struct pci_dev *pcidev,
320 		       struct uart_8250_port *port, int idx)
321 {
322 	unsigned int offset = idx * 0x200;
323 	unsigned int baud = 1843200;
324 
325 	port->port.uartclk = baud * 16;
326 	return default_setup(priv, pcidev, idx, offset, port);
327 }
328 
329 static int
330 pci_xr17c154_setup(struct exar8250 *priv, struct pci_dev *pcidev,
331 		   struct uart_8250_port *port, int idx)
332 {
333 	unsigned int offset = idx * 0x200;
334 	unsigned int baud = 921600;
335 
336 	port->port.uartclk = baud * 16;
337 	return default_setup(priv, pcidev, idx, offset, port);
338 }
339 
340 static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
341 {
342 	/*
343 	 * The Commtech adapters required the MPIOs to be driven low. The Exar
344 	 * devices will export them as GPIOs, so we pre-configure them safely
345 	 * as inputs.
346 	 */
347 
348 	u8 dir = 0x00;
349 
350 	if  ((pcidev->vendor == PCI_VENDOR_ID_EXAR) &&
351 		(pcidev->subsystem_vendor != PCI_VENDOR_ID_SEALEVEL)) {
352 		// Configure GPIO as inputs for Commtech adapters
353 		dir = 0xff;
354 	} else {
355 		// Configure GPIO as outputs for SeaLevel adapters
356 		dir = 0x00;
357 	}
358 
359 	writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
360 	writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
361 	writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
362 	writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
363 	writeb(dir,  p + UART_EXAR_MPIOSEL_7_0);
364 	writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
365 	writeb(0x00, p + UART_EXAR_MPIOINT_15_8);
366 	writeb(0x00, p + UART_EXAR_MPIOLVL_15_8);
367 	writeb(0x00, p + UART_EXAR_MPIO3T_15_8);
368 	writeb(0x00, p + UART_EXAR_MPIOINV_15_8);
369 	writeb(dir,  p + UART_EXAR_MPIOSEL_15_8);
370 	writeb(0x00, p + UART_EXAR_MPIOOD_15_8);
371 }
372 
373 static struct platform_device *__xr17v35x_register_gpio(struct pci_dev *pcidev,
374 							const struct software_node *node)
375 {
376 	struct platform_device *pdev;
377 
378 	pdev = platform_device_alloc("gpio_exar", PLATFORM_DEVID_AUTO);
379 	if (!pdev)
380 		return NULL;
381 
382 	pdev->dev.parent = &pcidev->dev;
383 	device_set_node(&pdev->dev, dev_fwnode(&pcidev->dev));
384 
385 	if (device_add_software_node(&pdev->dev, node) < 0 ||
386 	    platform_device_add(pdev) < 0) {
387 		platform_device_put(pdev);
388 		return NULL;
389 	}
390 
391 	return pdev;
392 }
393 
394 static void __xr17v35x_unregister_gpio(struct platform_device *pdev)
395 {
396 	device_remove_software_node(&pdev->dev);
397 	platform_device_unregister(pdev);
398 }
399 
400 static const struct property_entry exar_gpio_properties[] = {
401 	PROPERTY_ENTRY_U32("exar,first-pin", 0),
402 	PROPERTY_ENTRY_U32("ngpios", 16),
403 	{ }
404 };
405 
406 static const struct software_node exar_gpio_node = {
407 	.properties = exar_gpio_properties,
408 };
409 
410 static int xr17v35x_register_gpio(struct pci_dev *pcidev, struct uart_8250_port *port)
411 {
412 	if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
413 		port->port.private_data =
414 			__xr17v35x_register_gpio(pcidev, &exar_gpio_node);
415 
416 	return 0;
417 }
418 
419 static void xr17v35x_unregister_gpio(struct uart_8250_port *port)
420 {
421 	if (!port->port.private_data)
422 		return;
423 
424 	__xr17v35x_unregister_gpio(port->port.private_data);
425 	port->port.private_data = NULL;
426 }
427 
428 static int generic_rs485_config(struct uart_port *port, struct ktermios *termios,
429 				struct serial_rs485 *rs485)
430 {
431 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
432 	u8 __iomem *p = port->membase;
433 	u8 value;
434 
435 	value = readb(p + UART_EXAR_FCTR);
436 	if (is_rs485)
437 		value |= UART_FCTR_EXAR_485;
438 	else
439 		value &= ~UART_FCTR_EXAR_485;
440 
441 	writeb(value, p + UART_EXAR_FCTR);
442 
443 	if (is_rs485)
444 		writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR);
445 
446 	return 0;
447 }
448 
449 static int sealevel_rs485_config(struct uart_port *port, struct ktermios *termios,
450 				  struct serial_rs485 *rs485)
451 {
452 	u8 __iomem *p = port->membase;
453 	u8 old_lcr;
454 	u8 efr;
455 	u8 dld;
456 	int ret;
457 
458 	ret = generic_rs485_config(port, termios, rs485);
459 	if (ret)
460 		return ret;
461 
462 	if (rs485->flags & SER_RS485_ENABLED) {
463 		old_lcr = readb(p + UART_LCR);
464 
465 		/* Set EFR[4]=1 to enable enhanced feature registers */
466 		efr = readb(p + UART_XR_EFR);
467 		efr |= UART_EFR_ECB;
468 		writeb(efr, p + UART_XR_EFR);
469 
470 		/* Set MCR to use DTR as Auto-RS485 Enable signal */
471 		writeb(UART_MCR_OUT1, p + UART_MCR);
472 
473 		/* Set LCR[7]=1 to enable access to DLD register */
474 		writeb(old_lcr | UART_LCR_DLAB, p + UART_LCR);
475 
476 		/* Set DLD[7]=1 for inverted RS485 Enable logic */
477 		dld = readb(p + UART_EXAR_DLD);
478 		dld |= UART_EXAR_DLD_485_POLARITY;
479 		writeb(dld, p + UART_EXAR_DLD);
480 
481 		writeb(old_lcr, p + UART_LCR);
482 	}
483 
484 	return 0;
485 }
486 
487 static const struct serial_rs485 generic_rs485_supported = {
488 	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND,
489 };
490 
491 static const struct exar8250_platform exar8250_default_platform = {
492 	.register_gpio = xr17v35x_register_gpio,
493 	.unregister_gpio = xr17v35x_unregister_gpio,
494 	.rs485_config = generic_rs485_config,
495 	.rs485_supported = &generic_rs485_supported,
496 };
497 
498 static int iot2040_rs485_config(struct uart_port *port, struct ktermios *termios,
499 				struct serial_rs485 *rs485)
500 {
501 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
502 	u8 __iomem *p = port->membase;
503 	u8 mask = IOT2040_UART1_MASK;
504 	u8 mode, value;
505 
506 	if (is_rs485) {
507 		if (rs485->flags & SER_RS485_RX_DURING_TX)
508 			mode = IOT2040_UART_MODE_RS422;
509 		else
510 			mode = IOT2040_UART_MODE_RS485;
511 
512 		if (rs485->flags & SER_RS485_TERMINATE_BUS)
513 			mode |= IOT2040_UART_TERMINATE_BUS;
514 	} else {
515 		mode = IOT2040_UART_MODE_RS232;
516 	}
517 
518 	if (port->line == 3) {
519 		mask <<= IOT2040_UART2_SHIFT;
520 		mode <<= IOT2040_UART2_SHIFT;
521 	}
522 
523 	value = readb(p + UART_EXAR_MPIOLVL_7_0);
524 	value &= ~mask;
525 	value |= mode;
526 	writeb(value, p + UART_EXAR_MPIOLVL_7_0);
527 
528 	return generic_rs485_config(port, termios, rs485);
529 }
530 
531 static const struct serial_rs485 iot2040_rs485_supported = {
532 	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
533 		 SER_RS485_RX_DURING_TX | SER_RS485_TERMINATE_BUS,
534 };
535 
536 static const struct property_entry iot2040_gpio_properties[] = {
537 	PROPERTY_ENTRY_U32("exar,first-pin", 10),
538 	PROPERTY_ENTRY_U32("ngpios", 1),
539 	{ }
540 };
541 
542 static const struct software_node iot2040_gpio_node = {
543 	.properties = iot2040_gpio_properties,
544 };
545 
546 static int iot2040_register_gpio(struct pci_dev *pcidev,
547 			      struct uart_8250_port *port)
548 {
549 	u8 __iomem *p = port->port.membase;
550 
551 	writeb(IOT2040_UARTS_DEFAULT_MODE, p + UART_EXAR_MPIOLVL_7_0);
552 	writeb(IOT2040_UARTS_GPIO_LO_MODE, p + UART_EXAR_MPIOSEL_7_0);
553 	writeb(IOT2040_UARTS_ENABLE, p + UART_EXAR_MPIOLVL_15_8);
554 	writeb(IOT2040_UARTS_GPIO_HI_MODE, p + UART_EXAR_MPIOSEL_15_8);
555 
556 	port->port.private_data =
557 		__xr17v35x_register_gpio(pcidev, &iot2040_gpio_node);
558 
559 	return 0;
560 }
561 
562 static const struct exar8250_platform iot2040_platform = {
563 	.rs485_config = iot2040_rs485_config,
564 	.rs485_supported = &iot2040_rs485_supported,
565 	.register_gpio = iot2040_register_gpio,
566 	.unregister_gpio = xr17v35x_unregister_gpio,
567 };
568 
569 /*
570  * For SIMATIC IOT2000, only IOT2040 and its variants have the Exar device,
571  * IOT2020 doesn't have. Therefore it is sufficient to match on the common
572  * board name after the device was found.
573  */
574 static const struct dmi_system_id exar_platforms[] = {
575 	{
576 		.matches = {
577 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
578 		},
579 		.driver_data = (void *)&iot2040_platform,
580 	},
581 	{}
582 };
583 
584 static const struct exar8250_platform *exar_get_platform(void)
585 {
586 	const struct dmi_system_id *dmi_match;
587 
588 	dmi_match = dmi_first_match(exar_platforms);
589 	if (dmi_match)
590 		return dmi_match->driver_data;
591 
592 	return &exar8250_default_platform;
593 }
594 
595 static int
596 pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
597 		   struct uart_8250_port *port, int idx)
598 {
599 	const struct exar8250_platform *platform = exar_get_platform();
600 	unsigned int offset = idx * 0x400;
601 	unsigned int baud = 7812500;
602 	u8 __iomem *p;
603 	int ret;
604 
605 	port->port.uartclk = baud * 16;
606 	port->port.rs485_config = platform->rs485_config;
607 	port->port.rs485_supported = *(platform->rs485_supported);
608 
609 	if (pcidev->subsystem_vendor == PCI_VENDOR_ID_SEALEVEL)
610 		port->port.rs485_config = sealevel_rs485_config;
611 
612 	/*
613 	 * Setup the UART clock for the devices on expansion slot to
614 	 * half the clock speed of the main chip (which is 125MHz)
615 	 */
616 	if (idx >= 8)
617 		port->port.uartclk /= 2;
618 
619 	ret = default_setup(priv, pcidev, idx, offset, port);
620 	if (ret)
621 		return ret;
622 
623 	p = port->port.membase;
624 
625 	writeb(0x00, p + UART_EXAR_8XMODE);
626 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
627 	writeb(128, p + UART_EXAR_TXTRG);
628 	writeb(128, p + UART_EXAR_RXTRG);
629 
630 	if (idx == 0) {
631 		/* Setup Multipurpose Input/Output pins. */
632 		setup_gpio(pcidev, p);
633 
634 		ret = platform->register_gpio(pcidev, port);
635 	}
636 
637 	return ret;
638 }
639 
640 static void pci_xr17v35x_exit(struct pci_dev *pcidev)
641 {
642 	const struct exar8250_platform *platform = exar_get_platform();
643 	struct exar8250 *priv = pci_get_drvdata(pcidev);
644 	struct uart_8250_port *port = serial8250_get_port(priv->line[0]);
645 
646 	platform->unregister_gpio(port);
647 }
648 
649 static inline void exar_misc_clear(struct exar8250 *priv)
650 {
651 	/* Clear all PCI interrupts by reading INT0. No effect on IIR */
652 	readb(priv->virt + UART_EXAR_INT0);
653 
654 	/* Clear INT0 for Expansion Interface slave ports, too */
655 	if (priv->board->num_ports > 8)
656 		readb(priv->virt + 0x2000 + UART_EXAR_INT0);
657 }
658 
659 /*
660  * These Exar UARTs have an extra interrupt indicator that could fire for a
661  * few interrupts that are not presented/cleared through IIR.  One of which is
662  * a wakeup interrupt when coming out of sleep.  These interrupts are only
663  * cleared by reading global INT0 or INT1 registers as interrupts are
664  * associated with channel 0. The INT[3:0] registers _are_ accessible from each
665  * channel's address space, but for the sake of bus efficiency we register a
666  * dedicated handler at the PCI device level to handle them.
667  */
668 static irqreturn_t exar_misc_handler(int irq, void *data)
669 {
670 	exar_misc_clear(data);
671 
672 	return IRQ_HANDLED;
673 }
674 
675 static int
676 exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent)
677 {
678 	unsigned int nr_ports, i, bar = 0, maxnr;
679 	struct exar8250_board *board;
680 	struct uart_8250_port uart;
681 	struct exar8250 *priv;
682 	int rc;
683 
684 	board = (struct exar8250_board *)ent->driver_data;
685 	if (!board)
686 		return -EINVAL;
687 
688 	rc = pcim_enable_device(pcidev);
689 	if (rc)
690 		return rc;
691 
692 	maxnr = pci_resource_len(pcidev, bar) >> (board->reg_shift + 3);
693 
694 	if (pcidev->vendor == PCI_VENDOR_ID_ACCESSIO)
695 		nr_ports = BIT(((pcidev->device & 0x38) >> 3) - 1);
696 	else if (board->num_ports)
697 		nr_ports = board->num_ports;
698 	else
699 		nr_ports = pcidev->device & 0x0f;
700 
701 	priv = devm_kzalloc(&pcidev->dev, struct_size(priv, line, nr_ports), GFP_KERNEL);
702 	if (!priv)
703 		return -ENOMEM;
704 
705 	priv->board = board;
706 	priv->virt = pcim_iomap(pcidev, bar, 0);
707 	if (!priv->virt)
708 		return -ENOMEM;
709 
710 	pci_set_master(pcidev);
711 
712 	rc = pci_alloc_irq_vectors(pcidev, 1, 1, PCI_IRQ_ALL_TYPES);
713 	if (rc < 0)
714 		return rc;
715 
716 	memset(&uart, 0, sizeof(uart));
717 	uart.port.flags = UPF_SHARE_IRQ | UPF_EXAR_EFR | UPF_FIXED_TYPE | UPF_FIXED_PORT;
718 	uart.port.irq = pci_irq_vector(pcidev, 0);
719 	uart.port.dev = &pcidev->dev;
720 
721 	/* Clear interrupts */
722 	exar_misc_clear(priv);
723 
724 	rc = devm_request_irq(&pcidev->dev, uart.port.irq, exar_misc_handler,
725 			 IRQF_SHARED, "exar_uart", priv);
726 	if (rc)
727 		return rc;
728 
729 	for (i = 0; i < nr_ports && i < maxnr; i++) {
730 		rc = board->setup(priv, pcidev, &uart, i);
731 		if (rc) {
732 			dev_err(&pcidev->dev, "Failed to setup port %u\n", i);
733 			break;
734 		}
735 
736 		dev_dbg(&pcidev->dev, "Setup PCI port: port %lx, irq %d, type %d\n",
737 			uart.port.iobase, uart.port.irq, uart.port.iotype);
738 
739 		priv->line[i] = serial8250_register_8250_port(&uart);
740 		if (priv->line[i] < 0) {
741 			dev_err(&pcidev->dev,
742 				"Couldn't register serial port %lx, irq %d, type %d, error %d\n",
743 				uart.port.iobase, uart.port.irq,
744 				uart.port.iotype, priv->line[i]);
745 			break;
746 		}
747 	}
748 	priv->nr = i;
749 	pci_set_drvdata(pcidev, priv);
750 	return 0;
751 }
752 
753 static void exar_pci_remove(struct pci_dev *pcidev)
754 {
755 	struct exar8250 *priv = pci_get_drvdata(pcidev);
756 	unsigned int i;
757 
758 	for (i = 0; i < priv->nr; i++)
759 		serial8250_unregister_port(priv->line[i]);
760 
761 	/* Ensure that every init quirk is properly torn down */
762 	if (priv->board->exit)
763 		priv->board->exit(pcidev);
764 }
765 
766 static int exar_suspend(struct device *dev)
767 {
768 	struct exar8250 *priv = dev_get_drvdata(dev);
769 	unsigned int i;
770 
771 	for (i = 0; i < priv->nr; i++)
772 		if (priv->line[i] >= 0)
773 			serial8250_suspend_port(priv->line[i]);
774 
775 	return 0;
776 }
777 
778 static int exar_resume(struct device *dev)
779 {
780 	struct exar8250 *priv = dev_get_drvdata(dev);
781 	unsigned int i;
782 
783 	exar_misc_clear(priv);
784 
785 	for (i = 0; i < priv->nr; i++)
786 		if (priv->line[i] >= 0)
787 			serial8250_resume_port(priv->line[i]);
788 
789 	return 0;
790 }
791 
792 static DEFINE_SIMPLE_DEV_PM_OPS(exar_pci_pm, exar_suspend, exar_resume);
793 
794 static const struct exar8250_board pbn_fastcom335_2 = {
795 	.num_ports	= 2,
796 	.setup		= pci_fastcom335_setup,
797 };
798 
799 static const struct exar8250_board pbn_fastcom335_4 = {
800 	.num_ports	= 4,
801 	.setup		= pci_fastcom335_setup,
802 };
803 
804 static const struct exar8250_board pbn_fastcom335_8 = {
805 	.num_ports	= 8,
806 	.setup		= pci_fastcom335_setup,
807 };
808 
809 static const struct exar8250_board pbn_connect = {
810 	.setup		= pci_connect_tech_setup,
811 };
812 
813 static const struct exar8250_board pbn_exar_ibm_saturn = {
814 	.num_ports	= 1,
815 	.setup		= pci_xr17c154_setup,
816 };
817 
818 static const struct exar8250_board pbn_exar_XR17C15x = {
819 	.setup		= pci_xr17c154_setup,
820 };
821 
822 static const struct exar8250_board pbn_exar_XR17V35x = {
823 	.setup		= pci_xr17v35x_setup,
824 	.exit		= pci_xr17v35x_exit,
825 };
826 
827 static const struct exar8250_board pbn_fastcom35x_2 = {
828 	.num_ports	= 2,
829 	.setup		= pci_xr17v35x_setup,
830 	.exit		= pci_xr17v35x_exit,
831 };
832 
833 static const struct exar8250_board pbn_fastcom35x_4 = {
834 	.num_ports	= 4,
835 	.setup		= pci_xr17v35x_setup,
836 	.exit		= pci_xr17v35x_exit,
837 };
838 
839 static const struct exar8250_board pbn_fastcom35x_8 = {
840 	.num_ports	= 8,
841 	.setup		= pci_xr17v35x_setup,
842 	.exit		= pci_xr17v35x_exit,
843 };
844 
845 static const struct exar8250_board pbn_exar_XR17V4358 = {
846 	.num_ports	= 12,
847 	.setup		= pci_xr17v35x_setup,
848 	.exit		= pci_xr17v35x_exit,
849 };
850 
851 static const struct exar8250_board pbn_exar_XR17V8358 = {
852 	.num_ports	= 16,
853 	.setup		= pci_xr17v35x_setup,
854 	.exit		= pci_xr17v35x_exit,
855 };
856 
857 #define CONNECT_DEVICE(devid, sdevid, bd) {				\
858 	PCI_DEVICE_SUB(							\
859 		PCI_VENDOR_ID_EXAR,					\
860 		PCI_DEVICE_ID_EXAR_##devid,				\
861 		PCI_SUBVENDOR_ID_CONNECT_TECH,				\
862 		PCI_SUBDEVICE_ID_CONNECT_TECH_PCI_##sdevid), 0, 0,	\
863 		(kernel_ulong_t)&bd					\
864 	}
865 
866 #define EXAR_DEVICE(vend, devid, bd) { PCI_DEVICE_DATA(vend, devid, &bd) }
867 
868 #define IBM_DEVICE(devid, sdevid, bd) {			\
869 	PCI_DEVICE_SUB(					\
870 		PCI_VENDOR_ID_EXAR,			\
871 		PCI_DEVICE_ID_EXAR_##devid,		\
872 		PCI_VENDOR_ID_IBM,			\
873 		PCI_SUBDEVICE_ID_IBM_##sdevid), 0, 0,	\
874 		(kernel_ulong_t)&bd			\
875 	}
876 
877 #define USR_DEVICE(devid, sdevid, bd) {			\
878 	PCI_DEVICE_SUB(					\
879 		PCI_VENDOR_ID_USR,			\
880 		PCI_DEVICE_ID_EXAR_##devid,		\
881 		PCI_VENDOR_ID_EXAR,			\
882 		PCI_SUBDEVICE_ID_USR_##sdevid), 0, 0,	\
883 		(kernel_ulong_t)&bd			\
884 	}
885 
886 static const struct pci_device_id exar_pci_tbl[] = {
887 	EXAR_DEVICE(ACCESSIO, COM_2S, pbn_exar_XR17C15x),
888 	EXAR_DEVICE(ACCESSIO, COM_4S, pbn_exar_XR17C15x),
889 	EXAR_DEVICE(ACCESSIO, COM_8S, pbn_exar_XR17C15x),
890 	EXAR_DEVICE(ACCESSIO, COM232_8, pbn_exar_XR17C15x),
891 	EXAR_DEVICE(ACCESSIO, COM_2SM, pbn_exar_XR17C15x),
892 	EXAR_DEVICE(ACCESSIO, COM_4SM, pbn_exar_XR17C15x),
893 	EXAR_DEVICE(ACCESSIO, COM_8SM, pbn_exar_XR17C15x),
894 
895 	CONNECT_DEVICE(XR17C152, UART_2_232, pbn_connect),
896 	CONNECT_DEVICE(XR17C154, UART_4_232, pbn_connect),
897 	CONNECT_DEVICE(XR17C158, UART_8_232, pbn_connect),
898 	CONNECT_DEVICE(XR17C152, UART_1_1, pbn_connect),
899 	CONNECT_DEVICE(XR17C154, UART_2_2, pbn_connect),
900 	CONNECT_DEVICE(XR17C158, UART_4_4, pbn_connect),
901 	CONNECT_DEVICE(XR17C152, UART_2, pbn_connect),
902 	CONNECT_DEVICE(XR17C154, UART_4, pbn_connect),
903 	CONNECT_DEVICE(XR17C158, UART_8, pbn_connect),
904 	CONNECT_DEVICE(XR17C152, UART_2_485, pbn_connect),
905 	CONNECT_DEVICE(XR17C154, UART_4_485, pbn_connect),
906 	CONNECT_DEVICE(XR17C158, UART_8_485, pbn_connect),
907 
908 	IBM_DEVICE(XR17C152, SATURN_SERIAL_ONE_PORT, pbn_exar_ibm_saturn),
909 
910 	/* USRobotics USR298x-OEM PCI Modems */
911 	USR_DEVICE(XR17C152, 2980, pbn_exar_XR17C15x),
912 	USR_DEVICE(XR17C152, 2981, pbn_exar_XR17C15x),
913 
914 	/* Exar Corp. XR17C15[248] Dual/Quad/Octal UART */
915 	EXAR_DEVICE(EXAR, XR17C152, pbn_exar_XR17C15x),
916 	EXAR_DEVICE(EXAR, XR17C154, pbn_exar_XR17C15x),
917 	EXAR_DEVICE(EXAR, XR17C158, pbn_exar_XR17C15x),
918 
919 	/* Exar Corp. XR17V[48]35[248] Dual/Quad/Octal/Hexa PCIe UARTs */
920 	EXAR_DEVICE(EXAR, XR17V352, pbn_exar_XR17V35x),
921 	EXAR_DEVICE(EXAR, XR17V354, pbn_exar_XR17V35x),
922 	EXAR_DEVICE(EXAR, XR17V358, pbn_exar_XR17V35x),
923 	EXAR_DEVICE(EXAR, XR17V4358, pbn_exar_XR17V4358),
924 	EXAR_DEVICE(EXAR, XR17V8358, pbn_exar_XR17V8358),
925 	EXAR_DEVICE(COMMTECH, 4222PCIE, pbn_fastcom35x_2),
926 	EXAR_DEVICE(COMMTECH, 4224PCIE, pbn_fastcom35x_4),
927 	EXAR_DEVICE(COMMTECH, 4228PCIE, pbn_fastcom35x_8),
928 
929 	EXAR_DEVICE(COMMTECH, 4222PCI335, pbn_fastcom335_2),
930 	EXAR_DEVICE(COMMTECH, 4224PCI335, pbn_fastcom335_4),
931 	EXAR_DEVICE(COMMTECH, 2324PCI335, pbn_fastcom335_4),
932 	EXAR_DEVICE(COMMTECH, 2328PCI335, pbn_fastcom335_8),
933 	{ 0, }
934 };
935 MODULE_DEVICE_TABLE(pci, exar_pci_tbl);
936 
937 static struct pci_driver exar_pci_driver = {
938 	.name		= "exar_serial",
939 	.probe		= exar_pci_probe,
940 	.remove		= exar_pci_remove,
941 	.driver         = {
942 		.pm     = pm_sleep_ptr(&exar_pci_pm),
943 	},
944 	.id_table	= exar_pci_tbl,
945 };
946 module_pci_driver(exar_pci_driver);
947 
948 MODULE_IMPORT_NS(SERIAL_8250_PCI);
949 MODULE_LICENSE("GPL");
950 MODULE_DESCRIPTION("Exar Serial Driver");
951 MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");
952