xref: /linux/drivers/tty/serial/8250/8250_exar.c (revision 34dc1baba215b826e454b8d19e4f24adbeb7d00d)
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/8250_pci.h>
22 #include <linux/delay.h>
23 
24 #include <asm/byteorder.h>
25 
26 #include "8250.h"
27 
28 #define PCI_DEVICE_ID_ACCESSIO_COM_2S		0x1052
29 #define PCI_DEVICE_ID_ACCESSIO_COM_4S		0x105d
30 #define PCI_DEVICE_ID_ACCESSIO_COM_8S		0x106c
31 #define PCI_DEVICE_ID_ACCESSIO_COM232_8		0x10a8
32 #define PCI_DEVICE_ID_ACCESSIO_COM_2SM		0x10d2
33 #define PCI_DEVICE_ID_ACCESSIO_COM_4SM		0x10db
34 #define PCI_DEVICE_ID_ACCESSIO_COM_8SM		0x10ea
35 
36 #define PCI_DEVICE_ID_COMMTECH_4224PCI335	0x0002
37 #define PCI_DEVICE_ID_COMMTECH_4222PCI335	0x0004
38 #define PCI_DEVICE_ID_COMMTECH_2324PCI335	0x000a
39 #define PCI_DEVICE_ID_COMMTECH_2328PCI335	0x000b
40 #define PCI_DEVICE_ID_COMMTECH_4224PCIE		0x0020
41 #define PCI_DEVICE_ID_COMMTECH_4228PCIE		0x0021
42 #define PCI_DEVICE_ID_COMMTECH_4222PCIE		0x0022
43 
44 #define PCI_DEVICE_ID_EXAR_XR17V4358		0x4358
45 #define PCI_DEVICE_ID_EXAR_XR17V8358		0x8358
46 
47 #define PCI_SUBDEVICE_ID_USR_2980		0x0128
48 #define PCI_SUBDEVICE_ID_USR_2981		0x0129
49 
50 #define PCI_DEVICE_ID_SEALEVEL_710xC		0x1001
51 #define PCI_DEVICE_ID_SEALEVEL_720xC		0x1002
52 #define PCI_DEVICE_ID_SEALEVEL_740xC		0x1004
53 #define PCI_DEVICE_ID_SEALEVEL_780xC		0x1008
54 #define PCI_DEVICE_ID_SEALEVEL_716xC		0x1010
55 
56 #define UART_EXAR_INT0		0x80
57 #define UART_EXAR_8XMODE	0x88	/* 8X sampling rate select */
58 #define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
59 #define UART_EXAR_DVID		0x8d	/* Device identification */
60 
61 #define UART_EXAR_FCTR		0x08	/* Feature Control Register */
62 #define UART_FCTR_EXAR_IRDA	0x10	/* IrDa data encode select */
63 #define UART_FCTR_EXAR_485	0x20	/* Auto 485 half duplex dir ctl */
64 #define UART_FCTR_EXAR_TRGA	0x00	/* FIFO trigger table A */
65 #define UART_FCTR_EXAR_TRGB	0x60	/* FIFO trigger table B */
66 #define UART_FCTR_EXAR_TRGC	0x80	/* FIFO trigger table C */
67 #define UART_FCTR_EXAR_TRGD	0xc0	/* FIFO trigger table D programmable */
68 
69 #define UART_EXAR_TXTRG		0x0a	/* Tx FIFO trigger level write-only */
70 #define UART_EXAR_RXTRG		0x0b	/* Rx FIFO trigger level write-only */
71 
72 #define UART_EXAR_MPIOINT_7_0	0x8f	/* MPIOINT[7:0] */
73 #define UART_EXAR_MPIOLVL_7_0	0x90	/* MPIOLVL[7:0] */
74 #define UART_EXAR_MPIO3T_7_0	0x91	/* MPIO3T[7:0] */
75 #define UART_EXAR_MPIOINV_7_0	0x92	/* MPIOINV[7:0] */
76 #define UART_EXAR_MPIOSEL_7_0	0x93	/* MPIOSEL[7:0] */
77 #define UART_EXAR_MPIOOD_7_0	0x94	/* MPIOOD[7:0] */
78 #define UART_EXAR_MPIOINT_15_8	0x95	/* MPIOINT[15:8] */
79 #define UART_EXAR_MPIOLVL_15_8	0x96	/* MPIOLVL[15:8] */
80 #define UART_EXAR_MPIO3T_15_8	0x97	/* MPIO3T[15:8] */
81 #define UART_EXAR_MPIOINV_15_8	0x98	/* MPIOINV[15:8] */
82 #define UART_EXAR_MPIOSEL_15_8	0x99	/* MPIOSEL[15:8] */
83 #define UART_EXAR_MPIOOD_15_8	0x9a	/* MPIOOD[15:8] */
84 
85 #define UART_EXAR_RS485_DLY(x)	((x) << 4)
86 
87 /*
88  * IOT2040 MPIO wiring semantics:
89  *
90  * MPIO		Port	Function
91  * ----		----	--------
92  * 0		2 	Mode bit 0
93  * 1		2	Mode bit 1
94  * 2		2	Terminate bus
95  * 3		-	<reserved>
96  * 4		3	Mode bit 0
97  * 5		3	Mode bit 1
98  * 6		3	Terminate bus
99  * 7		-	<reserved>
100  * 8		2	Enable
101  * 9		3	Enable
102  * 10		-	Red LED
103  * 11..15	-	<unused>
104  */
105 
106 /* IOT2040 MPIOs 0..7 */
107 #define IOT2040_UART_MODE_RS232		0x01
108 #define IOT2040_UART_MODE_RS485		0x02
109 #define IOT2040_UART_MODE_RS422		0x03
110 #define IOT2040_UART_TERMINATE_BUS	0x04
111 
112 #define IOT2040_UART1_MASK		0x0f
113 #define IOT2040_UART2_SHIFT		4
114 
115 #define IOT2040_UARTS_DEFAULT_MODE	0x11	/* both RS232 */
116 #define IOT2040_UARTS_GPIO_LO_MODE	0x88	/* reserved pins as input */
117 
118 /* IOT2040 MPIOs 8..15 */
119 #define IOT2040_UARTS_ENABLE		0x03
120 #define IOT2040_UARTS_GPIO_HI_MODE	0xF8	/* enable & LED as outputs */
121 
122 struct exar8250;
123 
124 struct exar8250_platform {
125 	int (*rs485_config)(struct uart_port *port, struct ktermios *termios,
126 			    struct serial_rs485 *rs485);
127 	const struct serial_rs485 *rs485_supported;
128 	int (*register_gpio)(struct pci_dev *, struct uart_8250_port *);
129 	void (*unregister_gpio)(struct uart_8250_port *);
130 };
131 
132 /**
133  * struct exar8250_board - board information
134  * @num_ports: number of serial ports
135  * @reg_shift: describes UART register mapping in PCI memory
136  * @setup: quirk run at ->probe() stage
137  * @exit: quirk run at ->remove() stage
138  */
139 struct exar8250_board {
140 	unsigned int num_ports;
141 	unsigned int reg_shift;
142 	int	(*setup)(struct exar8250 *, struct pci_dev *,
143 			 struct uart_8250_port *, int);
144 	void	(*exit)(struct pci_dev *pcidev);
145 };
146 
147 struct exar8250 {
148 	unsigned int		nr;
149 	struct exar8250_board	*board;
150 	void __iomem		*virt;
151 	int			line[];
152 };
153 
154 static void exar_pm(struct uart_port *port, unsigned int state, unsigned int old)
155 {
156 	/*
157 	 * Exar UARTs have a SLEEP register that enables or disables each UART
158 	 * to enter sleep mode separately. On the XR17V35x the register
159 	 * is accessible to each UART at the UART_EXAR_SLEEP offset, but
160 	 * the UART channel may only write to the corresponding bit.
161 	 */
162 	serial_port_out(port, UART_EXAR_SLEEP, state ? 0xff : 0);
163 }
164 
165 /*
166  * XR17V35x UARTs have an extra fractional divisor register (DLD)
167  * Calculate divisor with extra 4-bit fractional portion
168  */
169 static unsigned int xr17v35x_get_divisor(struct uart_port *p, unsigned int baud,
170 					 unsigned int *frac)
171 {
172 	unsigned int quot_16;
173 
174 	quot_16 = DIV_ROUND_CLOSEST(p->uartclk, baud);
175 	*frac = quot_16 & 0x0f;
176 
177 	return quot_16 >> 4;
178 }
179 
180 static void xr17v35x_set_divisor(struct uart_port *p, unsigned int baud,
181 				 unsigned int quot, unsigned int quot_frac)
182 {
183 	serial8250_do_set_divisor(p, baud, quot, quot_frac);
184 
185 	/* Preserve bits not related to baudrate; DLD[7:4]. */
186 	quot_frac |= serial_port_in(p, 0x2) & 0xf0;
187 	serial_port_out(p, 0x2, quot_frac);
188 }
189 
190 static int xr17v35x_startup(struct uart_port *port)
191 {
192 	/*
193 	 * First enable access to IER [7:5], ISR [5:4], FCR [5:4],
194 	 * MCR [7:5] and MSR [7:0]
195 	 */
196 	serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);
197 
198 	/*
199 	 * Make sure all interrups are masked until initialization is
200 	 * complete and the FIFOs are cleared
201 	 *
202 	 * Synchronize UART_IER access against the console.
203 	 */
204 	spin_lock_irq(&port->lock);
205 	serial_port_out(port, UART_IER, 0);
206 	spin_unlock_irq(&port->lock);
207 
208 	return serial8250_do_startup(port);
209 }
210 
211 static void exar_shutdown(struct uart_port *port)
212 {
213 	bool tx_complete = false;
214 	struct uart_8250_port *up = up_to_u8250p(port);
215 	struct circ_buf *xmit = &port->state->xmit;
216 	int i = 0;
217 	u16 lsr;
218 
219 	do {
220 		lsr = serial_in(up, UART_LSR);
221 		if (lsr & (UART_LSR_TEMT | UART_LSR_THRE))
222 			tx_complete = true;
223 		else
224 			tx_complete = false;
225 		usleep_range(1000, 1100);
226 	} while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000);
227 
228 	serial8250_do_shutdown(port);
229 }
230 
231 static int default_setup(struct exar8250 *priv, struct pci_dev *pcidev,
232 			 int idx, unsigned int offset,
233 			 struct uart_8250_port *port)
234 {
235 	const struct exar8250_board *board = priv->board;
236 	unsigned int bar = 0;
237 	unsigned char status;
238 
239 	port->port.iotype = UPIO_MEM;
240 	port->port.mapbase = pci_resource_start(pcidev, bar) + offset;
241 	port->port.membase = priv->virt + offset;
242 	port->port.regshift = board->reg_shift;
243 
244 	/*
245 	 * XR17V35x UARTs have an extra divisor register, DLD that gets enabled
246 	 * with when DLAB is set which will cause the device to incorrectly match
247 	 * and assign port type to PORT_16650. The EFR for this UART is found
248 	 * at offset 0x09. Instead check the Deice ID (DVID) register
249 	 * for a 2, 4 or 8 port UART.
250 	 */
251 	status = readb(port->port.membase + UART_EXAR_DVID);
252 	if (status == 0x82 || status == 0x84 || status == 0x88) {
253 		port->port.type = PORT_XR17V35X;
254 
255 		port->port.get_divisor = xr17v35x_get_divisor;
256 		port->port.set_divisor = xr17v35x_set_divisor;
257 
258 		port->port.startup = xr17v35x_startup;
259 	} else {
260 		port->port.type = PORT_XR17D15X;
261 	}
262 
263 	port->port.pm = exar_pm;
264 	port->port.shutdown = exar_shutdown;
265 
266 	return 0;
267 }
268 
269 static int
270 pci_fastcom335_setup(struct exar8250 *priv, struct pci_dev *pcidev,
271 		     struct uart_8250_port *port, int idx)
272 {
273 	unsigned int offset = idx * 0x200;
274 	unsigned int baud = 1843200;
275 	u8 __iomem *p;
276 	int err;
277 
278 	port->port.uartclk = baud * 16;
279 
280 	err = default_setup(priv, pcidev, idx, offset, port);
281 	if (err)
282 		return err;
283 
284 	p = port->port.membase;
285 
286 	writeb(0x00, p + UART_EXAR_8XMODE);
287 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
288 	writeb(32, p + UART_EXAR_TXTRG);
289 	writeb(32, p + UART_EXAR_RXTRG);
290 
291 	/*
292 	 * Setup Multipurpose Input/Output pins.
293 	 */
294 	if (idx == 0) {
295 		switch (pcidev->device) {
296 		case PCI_DEVICE_ID_COMMTECH_4222PCI335:
297 		case PCI_DEVICE_ID_COMMTECH_4224PCI335:
298 			writeb(0x78, p + UART_EXAR_MPIOLVL_7_0);
299 			writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
300 			writeb(0x00, p + UART_EXAR_MPIOSEL_7_0);
301 			break;
302 		case PCI_DEVICE_ID_COMMTECH_2324PCI335:
303 		case PCI_DEVICE_ID_COMMTECH_2328PCI335:
304 			writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
305 			writeb(0xc0, p + UART_EXAR_MPIOINV_7_0);
306 			writeb(0xc0, p + UART_EXAR_MPIOSEL_7_0);
307 			break;
308 		}
309 		writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
310 		writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
311 		writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
312 	}
313 
314 	return 0;
315 }
316 
317 static int
318 pci_connect_tech_setup(struct exar8250 *priv, struct pci_dev *pcidev,
319 		       struct uart_8250_port *port, int idx)
320 {
321 	unsigned int offset = idx * 0x200;
322 	unsigned int baud = 1843200;
323 
324 	port->port.uartclk = baud * 16;
325 	return default_setup(priv, pcidev, idx, offset, port);
326 }
327 
328 static int
329 pci_xr17c154_setup(struct exar8250 *priv, struct pci_dev *pcidev,
330 		   struct uart_8250_port *port, int idx)
331 {
332 	unsigned int offset = idx * 0x200;
333 	unsigned int baud = 921600;
334 
335 	port->port.uartclk = baud * 16;
336 	return default_setup(priv, pcidev, idx, offset, port);
337 }
338 
339 static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
340 {
341 	/*
342 	 * The Commtech adapters required the MPIOs to be driven low. The Exar
343 	 * devices will export them as GPIOs, so we pre-configure them safely
344 	 * as inputs.
345 	 */
346 
347 	u8 dir = 0x00;
348 
349 	if  ((pcidev->vendor == PCI_VENDOR_ID_EXAR) &&
350 		(pcidev->subsystem_vendor != PCI_VENDOR_ID_SEALEVEL)) {
351 		// Configure GPIO as inputs for Commtech adapters
352 		dir = 0xff;
353 	} else {
354 		// Configure GPIO as outputs for SeaLevel adapters
355 		dir = 0x00;
356 	}
357 
358 	writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
359 	writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
360 	writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
361 	writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
362 	writeb(dir,  p + UART_EXAR_MPIOSEL_7_0);
363 	writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
364 	writeb(0x00, p + UART_EXAR_MPIOINT_15_8);
365 	writeb(0x00, p + UART_EXAR_MPIOLVL_15_8);
366 	writeb(0x00, p + UART_EXAR_MPIO3T_15_8);
367 	writeb(0x00, p + UART_EXAR_MPIOINV_15_8);
368 	writeb(dir,  p + UART_EXAR_MPIOSEL_15_8);
369 	writeb(0x00, p + UART_EXAR_MPIOOD_15_8);
370 }
371 
372 static struct platform_device *__xr17v35x_register_gpio(struct pci_dev *pcidev,
373 							const struct software_node *node)
374 {
375 	struct platform_device *pdev;
376 
377 	pdev = platform_device_alloc("gpio_exar", PLATFORM_DEVID_AUTO);
378 	if (!pdev)
379 		return NULL;
380 
381 	pdev->dev.parent = &pcidev->dev;
382 	ACPI_COMPANION_SET(&pdev->dev, ACPI_COMPANION(&pcidev->dev));
383 
384 	if (device_add_software_node(&pdev->dev, node) < 0 ||
385 	    platform_device_add(pdev) < 0) {
386 		platform_device_put(pdev);
387 		return NULL;
388 	}
389 
390 	return pdev;
391 }
392 
393 static void __xr17v35x_unregister_gpio(struct platform_device *pdev)
394 {
395 	device_remove_software_node(&pdev->dev);
396 	platform_device_unregister(pdev);
397 }
398 
399 static const struct property_entry exar_gpio_properties[] = {
400 	PROPERTY_ENTRY_U32("exar,first-pin", 0),
401 	PROPERTY_ENTRY_U32("ngpios", 16),
402 	{ }
403 };
404 
405 static const struct software_node exar_gpio_node = {
406 	.properties = exar_gpio_properties,
407 };
408 
409 static int xr17v35x_register_gpio(struct pci_dev *pcidev, struct uart_8250_port *port)
410 {
411 	if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
412 		port->port.private_data =
413 			__xr17v35x_register_gpio(pcidev, &exar_gpio_node);
414 
415 	return 0;
416 }
417 
418 static void xr17v35x_unregister_gpio(struct uart_8250_port *port)
419 {
420 	if (!port->port.private_data)
421 		return;
422 
423 	__xr17v35x_unregister_gpio(port->port.private_data);
424 	port->port.private_data = NULL;
425 }
426 
427 static int generic_rs485_config(struct uart_port *port, struct ktermios *termios,
428 				struct serial_rs485 *rs485)
429 {
430 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
431 	u8 __iomem *p = port->membase;
432 	u8 value;
433 
434 	value = readb(p + UART_EXAR_FCTR);
435 	if (is_rs485)
436 		value |= UART_FCTR_EXAR_485;
437 	else
438 		value &= ~UART_FCTR_EXAR_485;
439 
440 	writeb(value, p + UART_EXAR_FCTR);
441 
442 	if (is_rs485)
443 		writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR);
444 
445 	return 0;
446 }
447 
448 static const struct serial_rs485 generic_rs485_supported = {
449 	.flags = SER_RS485_ENABLED,
450 };
451 
452 static const struct exar8250_platform exar8250_default_platform = {
453 	.register_gpio = xr17v35x_register_gpio,
454 	.unregister_gpio = xr17v35x_unregister_gpio,
455 	.rs485_config = generic_rs485_config,
456 	.rs485_supported = &generic_rs485_supported,
457 };
458 
459 static int iot2040_rs485_config(struct uart_port *port, struct ktermios *termios,
460 				struct serial_rs485 *rs485)
461 {
462 	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
463 	u8 __iomem *p = port->membase;
464 	u8 mask = IOT2040_UART1_MASK;
465 	u8 mode, value;
466 
467 	if (is_rs485) {
468 		if (rs485->flags & SER_RS485_RX_DURING_TX)
469 			mode = IOT2040_UART_MODE_RS422;
470 		else
471 			mode = IOT2040_UART_MODE_RS485;
472 
473 		if (rs485->flags & SER_RS485_TERMINATE_BUS)
474 			mode |= IOT2040_UART_TERMINATE_BUS;
475 	} else {
476 		mode = IOT2040_UART_MODE_RS232;
477 	}
478 
479 	if (port->line == 3) {
480 		mask <<= IOT2040_UART2_SHIFT;
481 		mode <<= IOT2040_UART2_SHIFT;
482 	}
483 
484 	value = readb(p + UART_EXAR_MPIOLVL_7_0);
485 	value &= ~mask;
486 	value |= mode;
487 	writeb(value, p + UART_EXAR_MPIOLVL_7_0);
488 
489 	return generic_rs485_config(port, termios, rs485);
490 }
491 
492 static const struct serial_rs485 iot2040_rs485_supported = {
493 	.flags = SER_RS485_ENABLED | SER_RS485_RX_DURING_TX | SER_RS485_TERMINATE_BUS,
494 };
495 
496 static const struct property_entry iot2040_gpio_properties[] = {
497 	PROPERTY_ENTRY_U32("exar,first-pin", 10),
498 	PROPERTY_ENTRY_U32("ngpios", 1),
499 	{ }
500 };
501 
502 static const struct software_node iot2040_gpio_node = {
503 	.properties = iot2040_gpio_properties,
504 };
505 
506 static int iot2040_register_gpio(struct pci_dev *pcidev,
507 			      struct uart_8250_port *port)
508 {
509 	u8 __iomem *p = port->port.membase;
510 
511 	writeb(IOT2040_UARTS_DEFAULT_MODE, p + UART_EXAR_MPIOLVL_7_0);
512 	writeb(IOT2040_UARTS_GPIO_LO_MODE, p + UART_EXAR_MPIOSEL_7_0);
513 	writeb(IOT2040_UARTS_ENABLE, p + UART_EXAR_MPIOLVL_15_8);
514 	writeb(IOT2040_UARTS_GPIO_HI_MODE, p + UART_EXAR_MPIOSEL_15_8);
515 
516 	port->port.private_data =
517 		__xr17v35x_register_gpio(pcidev, &iot2040_gpio_node);
518 
519 	return 0;
520 }
521 
522 static const struct exar8250_platform iot2040_platform = {
523 	.rs485_config = iot2040_rs485_config,
524 	.rs485_supported = &iot2040_rs485_supported,
525 	.register_gpio = iot2040_register_gpio,
526 	.unregister_gpio = xr17v35x_unregister_gpio,
527 };
528 
529 /*
530  * For SIMATIC IOT2000, only IOT2040 and its variants have the Exar device,
531  * IOT2020 doesn't have. Therefore it is sufficient to match on the common
532  * board name after the device was found.
533  */
534 static const struct dmi_system_id exar_platforms[] = {
535 	{
536 		.matches = {
537 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
538 		},
539 		.driver_data = (void *)&iot2040_platform,
540 	},
541 	{}
542 };
543 
544 static const struct exar8250_platform *exar_get_platform(void)
545 {
546 	const struct dmi_system_id *dmi_match;
547 
548 	dmi_match = dmi_first_match(exar_platforms);
549 	if (dmi_match)
550 		return dmi_match->driver_data;
551 
552 	return &exar8250_default_platform;
553 }
554 
555 static int
556 pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
557 		   struct uart_8250_port *port, int idx)
558 {
559 	const struct exar8250_platform *platform = exar_get_platform();
560 	unsigned int offset = idx * 0x400;
561 	unsigned int baud = 7812500;
562 	u8 __iomem *p;
563 	int ret;
564 
565 	port->port.uartclk = baud * 16;
566 	port->port.rs485_config = platform->rs485_config;
567 	port->port.rs485_supported = *(platform->rs485_supported);
568 
569 	/*
570 	 * Setup the UART clock for the devices on expansion slot to
571 	 * half the clock speed of the main chip (which is 125MHz)
572 	 */
573 	if (idx >= 8)
574 		port->port.uartclk /= 2;
575 
576 	ret = default_setup(priv, pcidev, idx, offset, port);
577 	if (ret)
578 		return ret;
579 
580 	p = port->port.membase;
581 
582 	writeb(0x00, p + UART_EXAR_8XMODE);
583 	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
584 	writeb(128, p + UART_EXAR_TXTRG);
585 	writeb(128, p + UART_EXAR_RXTRG);
586 
587 	if (idx == 0) {
588 		/* Setup Multipurpose Input/Output pins. */
589 		setup_gpio(pcidev, p);
590 
591 		ret = platform->register_gpio(pcidev, port);
592 	}
593 
594 	return ret;
595 }
596 
597 static void pci_xr17v35x_exit(struct pci_dev *pcidev)
598 {
599 	const struct exar8250_platform *platform = exar_get_platform();
600 	struct exar8250 *priv = pci_get_drvdata(pcidev);
601 	struct uart_8250_port *port = serial8250_get_port(priv->line[0]);
602 
603 	platform->unregister_gpio(port);
604 }
605 
606 static inline void exar_misc_clear(struct exar8250 *priv)
607 {
608 	/* Clear all PCI interrupts by reading INT0. No effect on IIR */
609 	readb(priv->virt + UART_EXAR_INT0);
610 
611 	/* Clear INT0 for Expansion Interface slave ports, too */
612 	if (priv->board->num_ports > 8)
613 		readb(priv->virt + 0x2000 + UART_EXAR_INT0);
614 }
615 
616 /*
617  * These Exar UARTs have an extra interrupt indicator that could fire for a
618  * few interrupts that are not presented/cleared through IIR.  One of which is
619  * a wakeup interrupt when coming out of sleep.  These interrupts are only
620  * cleared by reading global INT0 or INT1 registers as interrupts are
621  * associated with channel 0. The INT[3:0] registers _are_ accessible from each
622  * channel's address space, but for the sake of bus efficiency we register a
623  * dedicated handler at the PCI device level to handle them.
624  */
625 static irqreturn_t exar_misc_handler(int irq, void *data)
626 {
627 	exar_misc_clear(data);
628 
629 	return IRQ_HANDLED;
630 }
631 
632 static int
633 exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent)
634 {
635 	unsigned int nr_ports, i, bar = 0, maxnr;
636 	struct exar8250_board *board;
637 	struct uart_8250_port uart;
638 	struct exar8250 *priv;
639 	int rc;
640 
641 	board = (struct exar8250_board *)ent->driver_data;
642 	if (!board)
643 		return -EINVAL;
644 
645 	rc = pcim_enable_device(pcidev);
646 	if (rc)
647 		return rc;
648 
649 	maxnr = pci_resource_len(pcidev, bar) >> (board->reg_shift + 3);
650 
651 	if (pcidev->vendor == PCI_VENDOR_ID_ACCESSIO)
652 		nr_ports = BIT(((pcidev->device & 0x38) >> 3) - 1);
653 	else if (board->num_ports)
654 		nr_ports = board->num_ports;
655 	else if (pcidev->vendor == PCI_VENDOR_ID_SEALEVEL)
656 		nr_ports = pcidev->device & 0xff;
657 	else
658 		nr_ports = pcidev->device & 0x0f;
659 
660 	priv = devm_kzalloc(&pcidev->dev, struct_size(priv, line, nr_ports), GFP_KERNEL);
661 	if (!priv)
662 		return -ENOMEM;
663 
664 	priv->board = board;
665 	priv->virt = pcim_iomap(pcidev, bar, 0);
666 	if (!priv->virt)
667 		return -ENOMEM;
668 
669 	pci_set_master(pcidev);
670 
671 	rc = pci_alloc_irq_vectors(pcidev, 1, 1, PCI_IRQ_ALL_TYPES);
672 	if (rc < 0)
673 		return rc;
674 
675 	memset(&uart, 0, sizeof(uart));
676 	uart.port.flags = UPF_SHARE_IRQ | UPF_EXAR_EFR | UPF_FIXED_TYPE | UPF_FIXED_PORT;
677 	uart.port.irq = pci_irq_vector(pcidev, 0);
678 	uart.port.dev = &pcidev->dev;
679 
680 	rc = devm_request_irq(&pcidev->dev, uart.port.irq, exar_misc_handler,
681 			 IRQF_SHARED, "exar_uart", priv);
682 	if (rc)
683 		return rc;
684 
685 	/* Clear interrupts */
686 	exar_misc_clear(priv);
687 
688 	for (i = 0; i < nr_ports && i < maxnr; i++) {
689 		rc = board->setup(priv, pcidev, &uart, i);
690 		if (rc) {
691 			dev_err(&pcidev->dev, "Failed to setup port %u\n", i);
692 			break;
693 		}
694 
695 		dev_dbg(&pcidev->dev, "Setup PCI port: port %lx, irq %d, type %d\n",
696 			uart.port.iobase, uart.port.irq, uart.port.iotype);
697 
698 		priv->line[i] = serial8250_register_8250_port(&uart);
699 		if (priv->line[i] < 0) {
700 			dev_err(&pcidev->dev,
701 				"Couldn't register serial port %lx, irq %d, type %d, error %d\n",
702 				uart.port.iobase, uart.port.irq,
703 				uart.port.iotype, priv->line[i]);
704 			break;
705 		}
706 	}
707 	priv->nr = i;
708 	pci_set_drvdata(pcidev, priv);
709 	return 0;
710 }
711 
712 static void exar_pci_remove(struct pci_dev *pcidev)
713 {
714 	struct exar8250 *priv = pci_get_drvdata(pcidev);
715 	unsigned int i;
716 
717 	for (i = 0; i < priv->nr; i++)
718 		serial8250_unregister_port(priv->line[i]);
719 
720 	if (priv->board->exit)
721 		priv->board->exit(pcidev);
722 }
723 
724 static int __maybe_unused exar_suspend(struct device *dev)
725 {
726 	struct pci_dev *pcidev = to_pci_dev(dev);
727 	struct exar8250 *priv = pci_get_drvdata(pcidev);
728 	unsigned int i;
729 
730 	for (i = 0; i < priv->nr; i++)
731 		if (priv->line[i] >= 0)
732 			serial8250_suspend_port(priv->line[i]);
733 
734 	/* Ensure that every init quirk is properly torn down */
735 	if (priv->board->exit)
736 		priv->board->exit(pcidev);
737 
738 	return 0;
739 }
740 
741 static int __maybe_unused exar_resume(struct device *dev)
742 {
743 	struct exar8250 *priv = dev_get_drvdata(dev);
744 	unsigned int i;
745 
746 	exar_misc_clear(priv);
747 
748 	for (i = 0; i < priv->nr; i++)
749 		if (priv->line[i] >= 0)
750 			serial8250_resume_port(priv->line[i]);
751 
752 	return 0;
753 }
754 
755 static SIMPLE_DEV_PM_OPS(exar_pci_pm, exar_suspend, exar_resume);
756 
757 static const struct exar8250_board pbn_fastcom335_2 = {
758 	.num_ports	= 2,
759 	.setup		= pci_fastcom335_setup,
760 };
761 
762 static const struct exar8250_board pbn_fastcom335_4 = {
763 	.num_ports	= 4,
764 	.setup		= pci_fastcom335_setup,
765 };
766 
767 static const struct exar8250_board pbn_fastcom335_8 = {
768 	.num_ports	= 8,
769 	.setup		= pci_fastcom335_setup,
770 };
771 
772 static const struct exar8250_board pbn_connect = {
773 	.setup		= pci_connect_tech_setup,
774 };
775 
776 static const struct exar8250_board pbn_exar_ibm_saturn = {
777 	.num_ports	= 1,
778 	.setup		= pci_xr17c154_setup,
779 };
780 
781 static const struct exar8250_board pbn_exar_XR17C15x = {
782 	.setup		= pci_xr17c154_setup,
783 };
784 
785 static const struct exar8250_board pbn_exar_XR17V35x = {
786 	.setup		= pci_xr17v35x_setup,
787 	.exit		= pci_xr17v35x_exit,
788 };
789 
790 static const struct exar8250_board pbn_fastcom35x_2 = {
791 	.num_ports	= 2,
792 	.setup		= pci_xr17v35x_setup,
793 	.exit		= pci_xr17v35x_exit,
794 };
795 
796 static const struct exar8250_board pbn_fastcom35x_4 = {
797 	.num_ports	= 4,
798 	.setup		= pci_xr17v35x_setup,
799 	.exit		= pci_xr17v35x_exit,
800 };
801 
802 static const struct exar8250_board pbn_fastcom35x_8 = {
803 	.num_ports	= 8,
804 	.setup		= pci_xr17v35x_setup,
805 	.exit		= pci_xr17v35x_exit,
806 };
807 
808 static const struct exar8250_board pbn_exar_XR17V4358 = {
809 	.num_ports	= 12,
810 	.setup		= pci_xr17v35x_setup,
811 	.exit		= pci_xr17v35x_exit,
812 };
813 
814 static const struct exar8250_board pbn_exar_XR17V8358 = {
815 	.num_ports	= 16,
816 	.setup		= pci_xr17v35x_setup,
817 	.exit		= pci_xr17v35x_exit,
818 };
819 
820 #define CONNECT_DEVICE(devid, sdevid, bd) {				\
821 	PCI_DEVICE_SUB(							\
822 		PCI_VENDOR_ID_EXAR,					\
823 		PCI_DEVICE_ID_EXAR_##devid,				\
824 		PCI_SUBVENDOR_ID_CONNECT_TECH,				\
825 		PCI_SUBDEVICE_ID_CONNECT_TECH_PCI_##sdevid), 0, 0,	\
826 		(kernel_ulong_t)&bd					\
827 	}
828 
829 #define EXAR_DEVICE(vend, devid, bd) { PCI_DEVICE_DATA(vend, devid, &bd) }
830 
831 #define IBM_DEVICE(devid, sdevid, bd) {			\
832 	PCI_DEVICE_SUB(					\
833 		PCI_VENDOR_ID_EXAR,			\
834 		PCI_DEVICE_ID_EXAR_##devid,		\
835 		PCI_VENDOR_ID_IBM,			\
836 		PCI_SUBDEVICE_ID_IBM_##sdevid), 0, 0,	\
837 		(kernel_ulong_t)&bd			\
838 	}
839 
840 #define USR_DEVICE(devid, sdevid, bd) {			\
841 	PCI_DEVICE_SUB(					\
842 		PCI_VENDOR_ID_USR,			\
843 		PCI_DEVICE_ID_EXAR_##devid,		\
844 		PCI_VENDOR_ID_EXAR,			\
845 		PCI_SUBDEVICE_ID_USR_##sdevid), 0, 0,	\
846 		(kernel_ulong_t)&bd			\
847 	}
848 
849 static const struct pci_device_id exar_pci_tbl[] = {
850 	EXAR_DEVICE(ACCESSIO, COM_2S, pbn_exar_XR17C15x),
851 	EXAR_DEVICE(ACCESSIO, COM_4S, pbn_exar_XR17C15x),
852 	EXAR_DEVICE(ACCESSIO, COM_8S, pbn_exar_XR17C15x),
853 	EXAR_DEVICE(ACCESSIO, COM232_8, pbn_exar_XR17C15x),
854 	EXAR_DEVICE(ACCESSIO, COM_2SM, pbn_exar_XR17C15x),
855 	EXAR_DEVICE(ACCESSIO, COM_4SM, pbn_exar_XR17C15x),
856 	EXAR_DEVICE(ACCESSIO, COM_8SM, pbn_exar_XR17C15x),
857 
858 	CONNECT_DEVICE(XR17C152, UART_2_232, pbn_connect),
859 	CONNECT_DEVICE(XR17C154, UART_4_232, pbn_connect),
860 	CONNECT_DEVICE(XR17C158, UART_8_232, pbn_connect),
861 	CONNECT_DEVICE(XR17C152, UART_1_1, pbn_connect),
862 	CONNECT_DEVICE(XR17C154, UART_2_2, pbn_connect),
863 	CONNECT_DEVICE(XR17C158, UART_4_4, pbn_connect),
864 	CONNECT_DEVICE(XR17C152, UART_2, pbn_connect),
865 	CONNECT_DEVICE(XR17C154, UART_4, pbn_connect),
866 	CONNECT_DEVICE(XR17C158, UART_8, pbn_connect),
867 	CONNECT_DEVICE(XR17C152, UART_2_485, pbn_connect),
868 	CONNECT_DEVICE(XR17C154, UART_4_485, pbn_connect),
869 	CONNECT_DEVICE(XR17C158, UART_8_485, pbn_connect),
870 
871 	IBM_DEVICE(XR17C152, SATURN_SERIAL_ONE_PORT, pbn_exar_ibm_saturn),
872 
873 	/* USRobotics USR298x-OEM PCI Modems */
874 	USR_DEVICE(XR17C152, 2980, pbn_exar_XR17C15x),
875 	USR_DEVICE(XR17C152, 2981, pbn_exar_XR17C15x),
876 
877 	/* Exar Corp. XR17C15[248] Dual/Quad/Octal UART */
878 	EXAR_DEVICE(EXAR, XR17C152, pbn_exar_XR17C15x),
879 	EXAR_DEVICE(EXAR, XR17C154, pbn_exar_XR17C15x),
880 	EXAR_DEVICE(EXAR, XR17C158, pbn_exar_XR17C15x),
881 
882 	/* Exar Corp. XR17V[48]35[248] Dual/Quad/Octal/Hexa PCIe UARTs */
883 	EXAR_DEVICE(EXAR, XR17V352, pbn_exar_XR17V35x),
884 	EXAR_DEVICE(EXAR, XR17V354, pbn_exar_XR17V35x),
885 	EXAR_DEVICE(EXAR, XR17V358, pbn_exar_XR17V35x),
886 	EXAR_DEVICE(EXAR, XR17V4358, pbn_exar_XR17V4358),
887 	EXAR_DEVICE(EXAR, XR17V8358, pbn_exar_XR17V8358),
888 	EXAR_DEVICE(COMMTECH, 4222PCIE, pbn_fastcom35x_2),
889 	EXAR_DEVICE(COMMTECH, 4224PCIE, pbn_fastcom35x_4),
890 	EXAR_DEVICE(COMMTECH, 4228PCIE, pbn_fastcom35x_8),
891 
892 	EXAR_DEVICE(COMMTECH, 4222PCI335, pbn_fastcom335_2),
893 	EXAR_DEVICE(COMMTECH, 4224PCI335, pbn_fastcom335_4),
894 	EXAR_DEVICE(COMMTECH, 2324PCI335, pbn_fastcom335_4),
895 	EXAR_DEVICE(COMMTECH, 2328PCI335, pbn_fastcom335_8),
896 
897 	EXAR_DEVICE(SEALEVEL, 710xC, pbn_exar_XR17V35x),
898 	EXAR_DEVICE(SEALEVEL, 720xC, pbn_exar_XR17V35x),
899 	EXAR_DEVICE(SEALEVEL, 740xC, pbn_exar_XR17V35x),
900 	EXAR_DEVICE(SEALEVEL, 780xC, pbn_exar_XR17V35x),
901 	EXAR_DEVICE(SEALEVEL, 716xC, pbn_exar_XR17V35x),
902 	{ 0, }
903 };
904 MODULE_DEVICE_TABLE(pci, exar_pci_tbl);
905 
906 static struct pci_driver exar_pci_driver = {
907 	.name		= "exar_serial",
908 	.probe		= exar_pci_probe,
909 	.remove		= exar_pci_remove,
910 	.driver         = {
911 		.pm     = &exar_pci_pm,
912 	},
913 	.id_table	= exar_pci_tbl,
914 };
915 module_pci_driver(exar_pci_driver);
916 
917 MODULE_LICENSE("GPL");
918 MODULE_DESCRIPTION("Exar Serial Driver");
919 MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");
920