xref: /linux/drivers/tty/serial/8250/8250_exar.c (revision 021bc4b9)
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/acpi.h>
10 #include <linux/dmi.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/pci.h>
15 #include <linux/property.h>
16 #include <linux/serial_core.h>
17 #include <linux/serial_reg.h>
18 #include <linux/slab.h>
19 #include <linux/string.h>
20 #include <linux/tty.h>
21 #include <linux/delay.h>
22 
23 #include <asm/byteorder.h>
24 
25 #include "8250.h"
26 
27 #define PCI_DEVICE_ID_ACCESSIO_COM_2S		0x1052
28 #define PCI_DEVICE_ID_ACCESSIO_COM_4S		0x105d
29 #define PCI_DEVICE_ID_ACCESSIO_COM_8S		0x106c
30 #define PCI_DEVICE_ID_ACCESSIO_COM232_8		0x10a8
31 #define PCI_DEVICE_ID_ACCESSIO_COM_2SM		0x10d2
32 #define PCI_DEVICE_ID_ACCESSIO_COM_4SM		0x10db
33 #define PCI_DEVICE_ID_ACCESSIO_COM_8SM		0x10ea
34 
35 #define PCI_DEVICE_ID_COMMTECH_4224PCI335	0x0002
36 #define PCI_DEVICE_ID_COMMTECH_4222PCI335	0x0004
37 #define PCI_DEVICE_ID_COMMTECH_2324PCI335	0x000a
38 #define PCI_DEVICE_ID_COMMTECH_2328PCI335	0x000b
39 #define PCI_DEVICE_ID_COMMTECH_4224PCIE		0x0020
40 #define PCI_DEVICE_ID_COMMTECH_4228PCIE		0x0021
41 #define PCI_DEVICE_ID_COMMTECH_4222PCIE		0x0022
42 
43 #define PCI_DEVICE_ID_EXAR_XR17V4358		0x4358
44 #define PCI_DEVICE_ID_EXAR_XR17V8358		0x8358
45 
46 #define PCI_SUBDEVICE_ID_USR_2980		0x0128
47 #define PCI_SUBDEVICE_ID_USR_2981		0x0129
48 
49 #define UART_EXAR_INT0		0x80
50 #define UART_EXAR_8XMODE	0x88	/* 8X sampling rate select */
51 #define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
52 #define UART_EXAR_DVID		0x8d	/* Device identification */
53 
54 #define UART_EXAR_FCTR		0x08	/* Feature Control Register */
55 #define UART_FCTR_EXAR_IRDA	0x10	/* IrDa data encode select */
56 #define UART_FCTR_EXAR_485	0x20	/* Auto 485 half duplex dir ctl */
57 #define UART_FCTR_EXAR_TRGA	0x00	/* FIFO trigger table A */
58 #define UART_FCTR_EXAR_TRGB	0x60	/* FIFO trigger table B */
59 #define UART_FCTR_EXAR_TRGC	0x80	/* FIFO trigger table C */
60 #define UART_FCTR_EXAR_TRGD	0xc0	/* FIFO trigger table D programmable */
61 
62 #define UART_EXAR_TXTRG		0x0a	/* Tx FIFO trigger level write-only */
63 #define UART_EXAR_RXTRG		0x0b	/* Rx FIFO trigger level write-only */
64 
65 #define UART_EXAR_MPIOINT_7_0	0x8f	/* MPIOINT[7:0] */
66 #define UART_EXAR_MPIOLVL_7_0	0x90	/* MPIOLVL[7:0] */
67 #define UART_EXAR_MPIO3T_7_0	0x91	/* MPIO3T[7:0] */
68 #define UART_EXAR_MPIOINV_7_0	0x92	/* MPIOINV[7:0] */
69 #define UART_EXAR_MPIOSEL_7_0	0x93	/* MPIOSEL[7:0] */
70 #define UART_EXAR_MPIOOD_7_0	0x94	/* MPIOOD[7:0] */
71 #define UART_EXAR_MPIOINT_15_8	0x95	/* MPIOINT[15:8] */
72 #define UART_EXAR_MPIOLVL_15_8	0x96	/* MPIOLVL[15:8] */
73 #define UART_EXAR_MPIO3T_15_8	0x97	/* MPIO3T[15:8] */
74 #define UART_EXAR_MPIOINV_15_8	0x98	/* MPIOINV[15:8] */
75 #define UART_EXAR_MPIOSEL_15_8	0x99	/* MPIOSEL[15:8] */
76 #define UART_EXAR_MPIOOD_15_8	0x9a	/* MPIOOD[15:8] */
77 
78 #define UART_EXAR_RS485_DLY(x)	((x) << 4)
79 
80 #define UART_EXAR_DLD			0x02 /* Divisor Fractional */
81 #define UART_EXAR_DLD_485_POLARITY	0x80 /* RS-485 Enable Signal Polarity */
82 
83 /*
84  * IOT2040 MPIO wiring semantics:
85  *
86  * MPIO		Port	Function
87  * ----		----	--------
88  * 0		2 	Mode bit 0
89  * 1		2	Mode bit 1
90  * 2		2	Terminate bus
91  * 3		-	<reserved>
92  * 4		3	Mode bit 0
93  * 5		3	Mode bit 1
94  * 6		3	Terminate bus
95  * 7		-	<reserved>
96  * 8		2	Enable
97  * 9		3	Enable
98  * 10		-	Red LED
99  * 11..15	-	<unused>
100  */
101 
102 /* IOT2040 MPIOs 0..7 */
103 #define IOT2040_UART_MODE_RS232		0x01
104 #define IOT2040_UART_MODE_RS485		0x02
105 #define IOT2040_UART_MODE_RS422		0x03
106 #define IOT2040_UART_TERMINATE_BUS	0x04
107 
108 #define IOT2040_UART1_MASK		0x0f
109 #define IOT2040_UART2_SHIFT		4
110 
111 #define IOT2040_UARTS_DEFAULT_MODE	0x11	/* both RS232 */
112 #define IOT2040_UARTS_GPIO_LO_MODE	0x88	/* reserved pins as input */
113 
114 /* IOT2040 MPIOs 8..15 */
115 #define IOT2040_UARTS_ENABLE		0x03
116 #define IOT2040_UARTS_GPIO_HI_MODE	0xF8	/* enable & LED as outputs */
117 
118 struct exar8250;
119 
120 struct exar8250_platform {
121 	int (*rs485_config)(struct uart_port *port, struct ktermios *termios,
122 			    struct serial_rs485 *rs485);
123 	const struct serial_rs485 *rs485_supported;
124 	int (*register_gpio)(struct pci_dev *, struct uart_8250_port *);
125 	void (*unregister_gpio)(struct uart_8250_port *);
126 };
127 
128 /**
129  * struct exar8250_board - board information
130  * @num_ports: number of serial ports
131  * @reg_shift: describes UART register mapping in PCI memory
132  * @setup: quirk run at ->probe() stage
133  * @exit: quirk run at ->remove() stage
134  */
135 struct exar8250_board {
136 	unsigned int num_ports;
137 	unsigned int reg_shift;
138 	int	(*setup)(struct exar8250 *, struct pci_dev *,
139 			 struct uart_8250_port *, int);
140 	void	(*exit)(struct pci_dev *pcidev);
141 };
142 
143 struct exar8250 {
144 	unsigned int		nr;
145 	struct exar8250_board	*board;
146 	void __iomem		*virt;
147 	int			line[];
148 };
149 
150 static void exar_pm(struct uart_port *port, unsigned int state, unsigned int old)
151 {
152 	/*
153 	 * Exar UARTs have a SLEEP register that enables or disables each UART
154 	 * to enter sleep mode separately. On the XR17V35x the register
155 	 * is accessible to each UART at the UART_EXAR_SLEEP offset, but
156 	 * the UART channel may only write to the corresponding bit.
157 	 */
158 	serial_port_out(port, UART_EXAR_SLEEP, state ? 0xff : 0);
159 }
160 
161 /*
162  * XR17V35x UARTs have an extra fractional divisor register (DLD)
163  * Calculate divisor with extra 4-bit fractional portion
164  */
165 static unsigned int xr17v35x_get_divisor(struct uart_port *p, unsigned int baud,
166 					 unsigned int *frac)
167 {
168 	unsigned int quot_16;
169 
170 	quot_16 = DIV_ROUND_CLOSEST(p->uartclk, baud);
171 	*frac = quot_16 & 0x0f;
172 
173 	return quot_16 >> 4;
174 }
175 
176 static void xr17v35x_set_divisor(struct uart_port *p, unsigned int baud,
177 				 unsigned int quot, unsigned int quot_frac)
178 {
179 	serial8250_do_set_divisor(p, baud, quot, quot_frac);
180 
181 	/* Preserve bits not related to baudrate; DLD[7:4]. */
182 	quot_frac |= serial_port_in(p, 0x2) & 0xf0;
183 	serial_port_out(p, 0x2, quot_frac);
184 }
185 
186 static int xr17v35x_startup(struct uart_port *port)
187 {
188 	/*
189 	 * First enable access to IER [7:5], ISR [5:4], FCR [5:4],
190 	 * MCR [7:5] and MSR [7:0]
191 	 */
192 	serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);
193 
194 	/*
195 	 * Make sure all interrups are masked until initialization is
196 	 * complete and the FIFOs are cleared
197 	 *
198 	 * Synchronize UART_IER access against the console.
199 	 */
200 	uart_port_lock_irq(port);
201 	serial_port_out(port, UART_IER, 0);
202 	uart_port_unlock_irq(port);
203 
204 	return serial8250_do_startup(port);
205 }
206 
207 static void exar_shutdown(struct uart_port *port)
208 {
209 	bool tx_complete = false;
210 	struct uart_8250_port *up = up_to_u8250p(port);
211 	struct circ_buf *xmit = &port->state->xmit;
212 	int i = 0;
213 	u16 lsr;
214 
215 	do {
216 		lsr = serial_in(up, UART_LSR);
217 		if (lsr & (UART_LSR_TEMT | UART_LSR_THRE))
218 			tx_complete = true;
219 		else
220 			tx_complete = false;
221 		usleep_range(1000, 1100);
222 	} while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000);
223 
224 	serial8250_do_shutdown(port);
225 }
226 
227 static int default_setup(struct exar8250 *priv, struct pci_dev *pcidev,
228 			 int idx, unsigned int offset,
229 			 struct uart_8250_port *port)
230 {
231 	const struct exar8250_board *board = priv->board;
232 	unsigned int bar = 0;
233 	unsigned char status;
234 
235 	port->port.iotype = UPIO_MEM;
236 	port->port.mapbase = pci_resource_start(pcidev, bar) + offset;
237 	port->port.membase = priv->virt + offset;
238 	port->port.regshift = board->reg_shift;
239 
240 	/*
241 	 * XR17V35x UARTs have an extra divisor register, DLD that gets enabled
242 	 * with when DLAB is set which will cause the device to incorrectly match
243 	 * and assign port type to PORT_16650. The EFR for this UART is found
244 	 * at offset 0x09. Instead check the Deice ID (DVID) register
245 	 * for a 2, 4 or 8 port UART.
246 	 */
247 	status = readb(port->port.membase + UART_EXAR_DVID);
248 	if (status == 0x82 || status == 0x84 || status == 0x88) {
249 		port->port.type = PORT_XR17V35X;
250 
251 		port->port.get_divisor = xr17v35x_get_divisor;
252 		port->port.set_divisor = xr17v35x_set_divisor;
253 
254 		port->port.startup = xr17v35x_startup;
255 	} else {
256 		port->port.type = PORT_XR17D15X;
257 	}
258 
259 	port->port.pm = exar_pm;
260 	port->port.shutdown = exar_shutdown;
261 
262 	return 0;
263 }
264 
265 static int
266 pci_fastcom335_setup(struct exar8250 *priv, struct pci_dev *pcidev,
267 		     struct uart_8250_port *port, int idx)
268 {
269 	unsigned int offset = idx * 0x200;
270 	unsigned int baud = 1843200;
271 	u8 __iomem *p;
272 	int err;
273 
274 	port->port.uartclk = baud * 16;
275 
276 	err = default_setup(priv, pcidev, idx, offset, port);
277 	if (err)
278 		return err;
279 
280 	p = port->port.membase;
281 
282 	writeb(0x00, p + UART_EXAR_8XMODE);
283 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
284 	writeb(32, p + UART_EXAR_TXTRG);
285 	writeb(32, p + UART_EXAR_RXTRG);
286 
287 	/*
288 	 * Setup Multipurpose Input/Output pins.
289 	 */
290 	if (idx == 0) {
291 		switch (pcidev->device) {
292 		case PCI_DEVICE_ID_COMMTECH_4222PCI335:
293 		case PCI_DEVICE_ID_COMMTECH_4224PCI335:
294 			writeb(0x78, p + UART_EXAR_MPIOLVL_7_0);
295 			writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
296 			writeb(0x00, p + UART_EXAR_MPIOSEL_7_0);
297 			break;
298 		case PCI_DEVICE_ID_COMMTECH_2324PCI335:
299 		case PCI_DEVICE_ID_COMMTECH_2328PCI335:
300 			writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
301 			writeb(0xc0, p + UART_EXAR_MPIOINV_7_0);
302 			writeb(0xc0, p + UART_EXAR_MPIOSEL_7_0);
303 			break;
304 		}
305 		writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
306 		writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
307 		writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
308 	}
309 
310 	return 0;
311 }
312 
313 static int
314 pci_connect_tech_setup(struct exar8250 *priv, struct pci_dev *pcidev,
315 		       struct uart_8250_port *port, int idx)
316 {
317 	unsigned int offset = idx * 0x200;
318 	unsigned int baud = 1843200;
319 
320 	port->port.uartclk = baud * 16;
321 	return default_setup(priv, pcidev, idx, offset, port);
322 }
323 
324 static int
325 pci_xr17c154_setup(struct exar8250 *priv, struct pci_dev *pcidev,
326 		   struct uart_8250_port *port, int idx)
327 {
328 	unsigned int offset = idx * 0x200;
329 	unsigned int baud = 921600;
330 
331 	port->port.uartclk = baud * 16;
332 	return default_setup(priv, pcidev, idx, offset, port);
333 }
334 
335 static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
336 {
337 	/*
338 	 * The Commtech adapters required the MPIOs to be driven low. The Exar
339 	 * devices will export them as GPIOs, so we pre-configure them safely
340 	 * as inputs.
341 	 */
342 
343 	u8 dir = 0x00;
344 
345 	if  ((pcidev->vendor == PCI_VENDOR_ID_EXAR) &&
346 		(pcidev->subsystem_vendor != PCI_VENDOR_ID_SEALEVEL)) {
347 		// Configure GPIO as inputs for Commtech adapters
348 		dir = 0xff;
349 	} else {
350 		// Configure GPIO as outputs for SeaLevel adapters
351 		dir = 0x00;
352 	}
353 
354 	writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
355 	writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
356 	writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
357 	writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
358 	writeb(dir,  p + UART_EXAR_MPIOSEL_7_0);
359 	writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
360 	writeb(0x00, p + UART_EXAR_MPIOINT_15_8);
361 	writeb(0x00, p + UART_EXAR_MPIOLVL_15_8);
362 	writeb(0x00, p + UART_EXAR_MPIO3T_15_8);
363 	writeb(0x00, p + UART_EXAR_MPIOINV_15_8);
364 	writeb(dir,  p + UART_EXAR_MPIOSEL_15_8);
365 	writeb(0x00, p + UART_EXAR_MPIOOD_15_8);
366 }
367 
368 static struct platform_device *__xr17v35x_register_gpio(struct pci_dev *pcidev,
369 							const struct software_node *node)
370 {
371 	struct platform_device *pdev;
372 
373 	pdev = platform_device_alloc("gpio_exar", PLATFORM_DEVID_AUTO);
374 	if (!pdev)
375 		return NULL;
376 
377 	pdev->dev.parent = &pcidev->dev;
378 	ACPI_COMPANION_SET(&pdev->dev, ACPI_COMPANION(&pcidev->dev));
379 
380 	if (device_add_software_node(&pdev->dev, node) < 0 ||
381 	    platform_device_add(pdev) < 0) {
382 		platform_device_put(pdev);
383 		return NULL;
384 	}
385 
386 	return pdev;
387 }
388 
389 static void __xr17v35x_unregister_gpio(struct platform_device *pdev)
390 {
391 	device_remove_software_node(&pdev->dev);
392 	platform_device_unregister(pdev);
393 }
394 
395 static const struct property_entry exar_gpio_properties[] = {
396 	PROPERTY_ENTRY_U32("exar,first-pin", 0),
397 	PROPERTY_ENTRY_U32("ngpios", 16),
398 	{ }
399 };
400 
401 static const struct software_node exar_gpio_node = {
402 	.properties = exar_gpio_properties,
403 };
404 
405 static int xr17v35x_register_gpio(struct pci_dev *pcidev, struct uart_8250_port *port)
406 {
407 	if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
408 		port->port.private_data =
409 			__xr17v35x_register_gpio(pcidev, &exar_gpio_node);
410 
411 	return 0;
412 }
413 
414 static void xr17v35x_unregister_gpio(struct uart_8250_port *port)
415 {
416 	if (!port->port.private_data)
417 		return;
418 
419 	__xr17v35x_unregister_gpio(port->port.private_data);
420 	port->port.private_data = NULL;
421 }
422 
423 static int generic_rs485_config(struct uart_port *port, struct ktermios *termios,
424 				struct serial_rs485 *rs485)
425 {
426 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
427 	u8 __iomem *p = port->membase;
428 	u8 value;
429 
430 	value = readb(p + UART_EXAR_FCTR);
431 	if (is_rs485)
432 		value |= UART_FCTR_EXAR_485;
433 	else
434 		value &= ~UART_FCTR_EXAR_485;
435 
436 	writeb(value, p + UART_EXAR_FCTR);
437 
438 	if (is_rs485)
439 		writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR);
440 
441 	return 0;
442 }
443 
444 static int sealevel_rs485_config(struct uart_port *port, struct ktermios *termios,
445 				  struct serial_rs485 *rs485)
446 {
447 	u8 __iomem *p = port->membase;
448 	u8 old_lcr;
449 	u8 efr;
450 	u8 dld;
451 	int ret;
452 
453 	ret = generic_rs485_config(port, termios, rs485);
454 	if (ret)
455 		return ret;
456 
457 	if (rs485->flags & SER_RS485_ENABLED) {
458 		old_lcr = readb(p + UART_LCR);
459 
460 		/* Set EFR[4]=1 to enable enhanced feature registers */
461 		efr = readb(p + UART_XR_EFR);
462 		efr |= UART_EFR_ECB;
463 		writeb(efr, p + UART_XR_EFR);
464 
465 		/* Set MCR to use DTR as Auto-RS485 Enable signal */
466 		writeb(UART_MCR_OUT1, p + UART_MCR);
467 
468 		/* Set LCR[7]=1 to enable access to DLD register */
469 		writeb(old_lcr | UART_LCR_DLAB, p + UART_LCR);
470 
471 		/* Set DLD[7]=1 for inverted RS485 Enable logic */
472 		dld = readb(p + UART_EXAR_DLD);
473 		dld |= UART_EXAR_DLD_485_POLARITY;
474 		writeb(dld, p + UART_EXAR_DLD);
475 
476 		writeb(old_lcr, p + UART_LCR);
477 	}
478 
479 	return 0;
480 }
481 
482 static const struct serial_rs485 generic_rs485_supported = {
483 	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND,
484 };
485 
486 static const struct exar8250_platform exar8250_default_platform = {
487 	.register_gpio = xr17v35x_register_gpio,
488 	.unregister_gpio = xr17v35x_unregister_gpio,
489 	.rs485_config = generic_rs485_config,
490 	.rs485_supported = &generic_rs485_supported,
491 };
492 
493 static int iot2040_rs485_config(struct uart_port *port, struct ktermios *termios,
494 				struct serial_rs485 *rs485)
495 {
496 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
497 	u8 __iomem *p = port->membase;
498 	u8 mask = IOT2040_UART1_MASK;
499 	u8 mode, value;
500 
501 	if (is_rs485) {
502 		if (rs485->flags & SER_RS485_RX_DURING_TX)
503 			mode = IOT2040_UART_MODE_RS422;
504 		else
505 			mode = IOT2040_UART_MODE_RS485;
506 
507 		if (rs485->flags & SER_RS485_TERMINATE_BUS)
508 			mode |= IOT2040_UART_TERMINATE_BUS;
509 	} else {
510 		mode = IOT2040_UART_MODE_RS232;
511 	}
512 
513 	if (port->line == 3) {
514 		mask <<= IOT2040_UART2_SHIFT;
515 		mode <<= IOT2040_UART2_SHIFT;
516 	}
517 
518 	value = readb(p + UART_EXAR_MPIOLVL_7_0);
519 	value &= ~mask;
520 	value |= mode;
521 	writeb(value, p + UART_EXAR_MPIOLVL_7_0);
522 
523 	return generic_rs485_config(port, termios, rs485);
524 }
525 
526 static const struct serial_rs485 iot2040_rs485_supported = {
527 	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
528 		 SER_RS485_RX_DURING_TX | SER_RS485_TERMINATE_BUS,
529 };
530 
531 static const struct property_entry iot2040_gpio_properties[] = {
532 	PROPERTY_ENTRY_U32("exar,first-pin", 10),
533 	PROPERTY_ENTRY_U32("ngpios", 1),
534 	{ }
535 };
536 
537 static const struct software_node iot2040_gpio_node = {
538 	.properties = iot2040_gpio_properties,
539 };
540 
541 static int iot2040_register_gpio(struct pci_dev *pcidev,
542 			      struct uart_8250_port *port)
543 {
544 	u8 __iomem *p = port->port.membase;
545 
546 	writeb(IOT2040_UARTS_DEFAULT_MODE, p + UART_EXAR_MPIOLVL_7_0);
547 	writeb(IOT2040_UARTS_GPIO_LO_MODE, p + UART_EXAR_MPIOSEL_7_0);
548 	writeb(IOT2040_UARTS_ENABLE, p + UART_EXAR_MPIOLVL_15_8);
549 	writeb(IOT2040_UARTS_GPIO_HI_MODE, p + UART_EXAR_MPIOSEL_15_8);
550 
551 	port->port.private_data =
552 		__xr17v35x_register_gpio(pcidev, &iot2040_gpio_node);
553 
554 	return 0;
555 }
556 
557 static const struct exar8250_platform iot2040_platform = {
558 	.rs485_config = iot2040_rs485_config,
559 	.rs485_supported = &iot2040_rs485_supported,
560 	.register_gpio = iot2040_register_gpio,
561 	.unregister_gpio = xr17v35x_unregister_gpio,
562 };
563 
564 /*
565  * For SIMATIC IOT2000, only IOT2040 and its variants have the Exar device,
566  * IOT2020 doesn't have. Therefore it is sufficient to match on the common
567  * board name after the device was found.
568  */
569 static const struct dmi_system_id exar_platforms[] = {
570 	{
571 		.matches = {
572 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
573 		},
574 		.driver_data = (void *)&iot2040_platform,
575 	},
576 	{}
577 };
578 
579 static const struct exar8250_platform *exar_get_platform(void)
580 {
581 	const struct dmi_system_id *dmi_match;
582 
583 	dmi_match = dmi_first_match(exar_platforms);
584 	if (dmi_match)
585 		return dmi_match->driver_data;
586 
587 	return &exar8250_default_platform;
588 }
589 
590 static int
591 pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
592 		   struct uart_8250_port *port, int idx)
593 {
594 	const struct exar8250_platform *platform = exar_get_platform();
595 	unsigned int offset = idx * 0x400;
596 	unsigned int baud = 7812500;
597 	u8 __iomem *p;
598 	int ret;
599 
600 	port->port.uartclk = baud * 16;
601 	port->port.rs485_config = platform->rs485_config;
602 	port->port.rs485_supported = *(platform->rs485_supported);
603 
604 	if (pcidev->subsystem_vendor == PCI_VENDOR_ID_SEALEVEL)
605 		port->port.rs485_config = sealevel_rs485_config;
606 
607 	/*
608 	 * Setup the UART clock for the devices on expansion slot to
609 	 * half the clock speed of the main chip (which is 125MHz)
610 	 */
611 	if (idx >= 8)
612 		port->port.uartclk /= 2;
613 
614 	ret = default_setup(priv, pcidev, idx, offset, port);
615 	if (ret)
616 		return ret;
617 
618 	p = port->port.membase;
619 
620 	writeb(0x00, p + UART_EXAR_8XMODE);
621 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
622 	writeb(128, p + UART_EXAR_TXTRG);
623 	writeb(128, p + UART_EXAR_RXTRG);
624 
625 	if (idx == 0) {
626 		/* Setup Multipurpose Input/Output pins. */
627 		setup_gpio(pcidev, p);
628 
629 		ret = platform->register_gpio(pcidev, port);
630 	}
631 
632 	return ret;
633 }
634 
635 static void pci_xr17v35x_exit(struct pci_dev *pcidev)
636 {
637 	const struct exar8250_platform *platform = exar_get_platform();
638 	struct exar8250 *priv = pci_get_drvdata(pcidev);
639 	struct uart_8250_port *port = serial8250_get_port(priv->line[0]);
640 
641 	platform->unregister_gpio(port);
642 }
643 
644 static inline void exar_misc_clear(struct exar8250 *priv)
645 {
646 	/* Clear all PCI interrupts by reading INT0. No effect on IIR */
647 	readb(priv->virt + UART_EXAR_INT0);
648 
649 	/* Clear INT0 for Expansion Interface slave ports, too */
650 	if (priv->board->num_ports > 8)
651 		readb(priv->virt + 0x2000 + UART_EXAR_INT0);
652 }
653 
654 /*
655  * These Exar UARTs have an extra interrupt indicator that could fire for a
656  * few interrupts that are not presented/cleared through IIR.  One of which is
657  * a wakeup interrupt when coming out of sleep.  These interrupts are only
658  * cleared by reading global INT0 or INT1 registers as interrupts are
659  * associated with channel 0. The INT[3:0] registers _are_ accessible from each
660  * channel's address space, but for the sake of bus efficiency we register a
661  * dedicated handler at the PCI device level to handle them.
662  */
663 static irqreturn_t exar_misc_handler(int irq, void *data)
664 {
665 	exar_misc_clear(data);
666 
667 	return IRQ_HANDLED;
668 }
669 
670 static int
671 exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent)
672 {
673 	unsigned int nr_ports, i, bar = 0, maxnr;
674 	struct exar8250_board *board;
675 	struct uart_8250_port uart;
676 	struct exar8250 *priv;
677 	int rc;
678 
679 	board = (struct exar8250_board *)ent->driver_data;
680 	if (!board)
681 		return -EINVAL;
682 
683 	rc = pcim_enable_device(pcidev);
684 	if (rc)
685 		return rc;
686 
687 	maxnr = pci_resource_len(pcidev, bar) >> (board->reg_shift + 3);
688 
689 	if (pcidev->vendor == PCI_VENDOR_ID_ACCESSIO)
690 		nr_ports = BIT(((pcidev->device & 0x38) >> 3) - 1);
691 	else if (board->num_ports)
692 		nr_ports = board->num_ports;
693 	else
694 		nr_ports = pcidev->device & 0x0f;
695 
696 	priv = devm_kzalloc(&pcidev->dev, struct_size(priv, line, nr_ports), GFP_KERNEL);
697 	if (!priv)
698 		return -ENOMEM;
699 
700 	priv->board = board;
701 	priv->virt = pcim_iomap(pcidev, bar, 0);
702 	if (!priv->virt)
703 		return -ENOMEM;
704 
705 	pci_set_master(pcidev);
706 
707 	rc = pci_alloc_irq_vectors(pcidev, 1, 1, PCI_IRQ_ALL_TYPES);
708 	if (rc < 0)
709 		return rc;
710 
711 	memset(&uart, 0, sizeof(uart));
712 	uart.port.flags = UPF_SHARE_IRQ | UPF_EXAR_EFR | UPF_FIXED_TYPE | UPF_FIXED_PORT;
713 	uart.port.irq = pci_irq_vector(pcidev, 0);
714 	uart.port.dev = &pcidev->dev;
715 
716 	rc = devm_request_irq(&pcidev->dev, uart.port.irq, exar_misc_handler,
717 			 IRQF_SHARED, "exar_uart", priv);
718 	if (rc)
719 		return rc;
720 
721 	/* Clear interrupts */
722 	exar_misc_clear(priv);
723 
724 	for (i = 0; i < nr_ports && i < maxnr; i++) {
725 		rc = board->setup(priv, pcidev, &uart, i);
726 		if (rc) {
727 			dev_err(&pcidev->dev, "Failed to setup port %u\n", i);
728 			break;
729 		}
730 
731 		dev_dbg(&pcidev->dev, "Setup PCI port: port %lx, irq %d, type %d\n",
732 			uart.port.iobase, uart.port.irq, uart.port.iotype);
733 
734 		priv->line[i] = serial8250_register_8250_port(&uart);
735 		if (priv->line[i] < 0) {
736 			dev_err(&pcidev->dev,
737 				"Couldn't register serial port %lx, irq %d, type %d, error %d\n",
738 				uart.port.iobase, uart.port.irq,
739 				uart.port.iotype, priv->line[i]);
740 			break;
741 		}
742 	}
743 	priv->nr = i;
744 	pci_set_drvdata(pcidev, priv);
745 	return 0;
746 }
747 
748 static void exar_pci_remove(struct pci_dev *pcidev)
749 {
750 	struct exar8250 *priv = pci_get_drvdata(pcidev);
751 	unsigned int i;
752 
753 	for (i = 0; i < priv->nr; i++)
754 		serial8250_unregister_port(priv->line[i]);
755 
756 	if (priv->board->exit)
757 		priv->board->exit(pcidev);
758 }
759 
760 static int __maybe_unused exar_suspend(struct device *dev)
761 {
762 	struct pci_dev *pcidev = to_pci_dev(dev);
763 	struct exar8250 *priv = pci_get_drvdata(pcidev);
764 	unsigned int i;
765 
766 	for (i = 0; i < priv->nr; i++)
767 		if (priv->line[i] >= 0)
768 			serial8250_suspend_port(priv->line[i]);
769 
770 	/* Ensure that every init quirk is properly torn down */
771 	if (priv->board->exit)
772 		priv->board->exit(pcidev);
773 
774 	return 0;
775 }
776 
777 static int __maybe_unused exar_resume(struct device *dev)
778 {
779 	struct exar8250 *priv = dev_get_drvdata(dev);
780 	unsigned int i;
781 
782 	exar_misc_clear(priv);
783 
784 	for (i = 0; i < priv->nr; i++)
785 		if (priv->line[i] >= 0)
786 			serial8250_resume_port(priv->line[i]);
787 
788 	return 0;
789 }
790 
791 static SIMPLE_DEV_PM_OPS(exar_pci_pm, exar_suspend, exar_resume);
792 
793 static const struct exar8250_board pbn_fastcom335_2 = {
794 	.num_ports	= 2,
795 	.setup		= pci_fastcom335_setup,
796 };
797 
798 static const struct exar8250_board pbn_fastcom335_4 = {
799 	.num_ports	= 4,
800 	.setup		= pci_fastcom335_setup,
801 };
802 
803 static const struct exar8250_board pbn_fastcom335_8 = {
804 	.num_ports	= 8,
805 	.setup		= pci_fastcom335_setup,
806 };
807 
808 static const struct exar8250_board pbn_connect = {
809 	.setup		= pci_connect_tech_setup,
810 };
811 
812 static const struct exar8250_board pbn_exar_ibm_saturn = {
813 	.num_ports	= 1,
814 	.setup		= pci_xr17c154_setup,
815 };
816 
817 static const struct exar8250_board pbn_exar_XR17C15x = {
818 	.setup		= pci_xr17c154_setup,
819 };
820 
821 static const struct exar8250_board pbn_exar_XR17V35x = {
822 	.setup		= pci_xr17v35x_setup,
823 	.exit		= pci_xr17v35x_exit,
824 };
825 
826 static const struct exar8250_board pbn_fastcom35x_2 = {
827 	.num_ports	= 2,
828 	.setup		= pci_xr17v35x_setup,
829 	.exit		= pci_xr17v35x_exit,
830 };
831 
832 static const struct exar8250_board pbn_fastcom35x_4 = {
833 	.num_ports	= 4,
834 	.setup		= pci_xr17v35x_setup,
835 	.exit		= pci_xr17v35x_exit,
836 };
837 
838 static const struct exar8250_board pbn_fastcom35x_8 = {
839 	.num_ports	= 8,
840 	.setup		= pci_xr17v35x_setup,
841 	.exit		= pci_xr17v35x_exit,
842 };
843 
844 static const struct exar8250_board pbn_exar_XR17V4358 = {
845 	.num_ports	= 12,
846 	.setup		= pci_xr17v35x_setup,
847 	.exit		= pci_xr17v35x_exit,
848 };
849 
850 static const struct exar8250_board pbn_exar_XR17V8358 = {
851 	.num_ports	= 16,
852 	.setup		= pci_xr17v35x_setup,
853 	.exit		= pci_xr17v35x_exit,
854 };
855 
856 #define CONNECT_DEVICE(devid, sdevid, bd) {				\
857 	PCI_DEVICE_SUB(							\
858 		PCI_VENDOR_ID_EXAR,					\
859 		PCI_DEVICE_ID_EXAR_##devid,				\
860 		PCI_SUBVENDOR_ID_CONNECT_TECH,				\
861 		PCI_SUBDEVICE_ID_CONNECT_TECH_PCI_##sdevid), 0, 0,	\
862 		(kernel_ulong_t)&bd					\
863 	}
864 
865 #define EXAR_DEVICE(vend, devid, bd) { PCI_DEVICE_DATA(vend, devid, &bd) }
866 
867 #define IBM_DEVICE(devid, sdevid, bd) {			\
868 	PCI_DEVICE_SUB(					\
869 		PCI_VENDOR_ID_EXAR,			\
870 		PCI_DEVICE_ID_EXAR_##devid,		\
871 		PCI_VENDOR_ID_IBM,			\
872 		PCI_SUBDEVICE_ID_IBM_##sdevid), 0, 0,	\
873 		(kernel_ulong_t)&bd			\
874 	}
875 
876 #define USR_DEVICE(devid, sdevid, bd) {			\
877 	PCI_DEVICE_SUB(					\
878 		PCI_VENDOR_ID_USR,			\
879 		PCI_DEVICE_ID_EXAR_##devid,		\
880 		PCI_VENDOR_ID_EXAR,			\
881 		PCI_SUBDEVICE_ID_USR_##sdevid), 0, 0,	\
882 		(kernel_ulong_t)&bd			\
883 	}
884 
885 static const struct pci_device_id exar_pci_tbl[] = {
886 	EXAR_DEVICE(ACCESSIO, COM_2S, pbn_exar_XR17C15x),
887 	EXAR_DEVICE(ACCESSIO, COM_4S, pbn_exar_XR17C15x),
888 	EXAR_DEVICE(ACCESSIO, COM_8S, pbn_exar_XR17C15x),
889 	EXAR_DEVICE(ACCESSIO, COM232_8, pbn_exar_XR17C15x),
890 	EXAR_DEVICE(ACCESSIO, COM_2SM, pbn_exar_XR17C15x),
891 	EXAR_DEVICE(ACCESSIO, COM_4SM, pbn_exar_XR17C15x),
892 	EXAR_DEVICE(ACCESSIO, COM_8SM, pbn_exar_XR17C15x),
893 
894 	CONNECT_DEVICE(XR17C152, UART_2_232, pbn_connect),
895 	CONNECT_DEVICE(XR17C154, UART_4_232, pbn_connect),
896 	CONNECT_DEVICE(XR17C158, UART_8_232, pbn_connect),
897 	CONNECT_DEVICE(XR17C152, UART_1_1, pbn_connect),
898 	CONNECT_DEVICE(XR17C154, UART_2_2, pbn_connect),
899 	CONNECT_DEVICE(XR17C158, UART_4_4, pbn_connect),
900 	CONNECT_DEVICE(XR17C152, UART_2, pbn_connect),
901 	CONNECT_DEVICE(XR17C154, UART_4, pbn_connect),
902 	CONNECT_DEVICE(XR17C158, UART_8, pbn_connect),
903 	CONNECT_DEVICE(XR17C152, UART_2_485, pbn_connect),
904 	CONNECT_DEVICE(XR17C154, UART_4_485, pbn_connect),
905 	CONNECT_DEVICE(XR17C158, UART_8_485, pbn_connect),
906 
907 	IBM_DEVICE(XR17C152, SATURN_SERIAL_ONE_PORT, pbn_exar_ibm_saturn),
908 
909 	/* USRobotics USR298x-OEM PCI Modems */
910 	USR_DEVICE(XR17C152, 2980, pbn_exar_XR17C15x),
911 	USR_DEVICE(XR17C152, 2981, pbn_exar_XR17C15x),
912 
913 	/* Exar Corp. XR17C15[248] Dual/Quad/Octal UART */
914 	EXAR_DEVICE(EXAR, XR17C152, pbn_exar_XR17C15x),
915 	EXAR_DEVICE(EXAR, XR17C154, pbn_exar_XR17C15x),
916 	EXAR_DEVICE(EXAR, XR17C158, pbn_exar_XR17C15x),
917 
918 	/* Exar Corp. XR17V[48]35[248] Dual/Quad/Octal/Hexa PCIe UARTs */
919 	EXAR_DEVICE(EXAR, XR17V352, pbn_exar_XR17V35x),
920 	EXAR_DEVICE(EXAR, XR17V354, pbn_exar_XR17V35x),
921 	EXAR_DEVICE(EXAR, XR17V358, pbn_exar_XR17V35x),
922 	EXAR_DEVICE(EXAR, XR17V4358, pbn_exar_XR17V4358),
923 	EXAR_DEVICE(EXAR, XR17V8358, pbn_exar_XR17V8358),
924 	EXAR_DEVICE(COMMTECH, 4222PCIE, pbn_fastcom35x_2),
925 	EXAR_DEVICE(COMMTECH, 4224PCIE, pbn_fastcom35x_4),
926 	EXAR_DEVICE(COMMTECH, 4228PCIE, pbn_fastcom35x_8),
927 
928 	EXAR_DEVICE(COMMTECH, 4222PCI335, pbn_fastcom335_2),
929 	EXAR_DEVICE(COMMTECH, 4224PCI335, pbn_fastcom335_4),
930 	EXAR_DEVICE(COMMTECH, 2324PCI335, pbn_fastcom335_4),
931 	EXAR_DEVICE(COMMTECH, 2328PCI335, pbn_fastcom335_8),
932 	{ 0, }
933 };
934 MODULE_DEVICE_TABLE(pci, exar_pci_tbl);
935 
936 static struct pci_driver exar_pci_driver = {
937 	.name		= "exar_serial",
938 	.probe		= exar_pci_probe,
939 	.remove		= exar_pci_remove,
940 	.driver         = {
941 		.pm     = &exar_pci_pm,
942 	},
943 	.id_table	= exar_pci_tbl,
944 };
945 module_pci_driver(exar_pci_driver);
946 
947 MODULE_LICENSE("GPL");
948 MODULE_DESCRIPTION("Exar Serial Driver");
949 MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");
950