xref: /linux/drivers/tty/mxser.c (revision f9bff0e31881d03badf191d3b0005839391f5f2b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *          mxser.c  -- MOXA Smartio/Industio family multiport serial driver.
4  *
5  *      Copyright (C) 1999-2006  Moxa Technologies (support@moxa.com).
6  *	Copyright (C) 2006-2008  Jiri Slaby <jirislaby@gmail.com>
7  *
8  *      This code is loosely based on the 1.8 moxa driver which is based on
9  *	Linux serial driver, written by Linus Torvalds, Theodore T'so and
10  *	others.
11  *
12  *	Fed through a cleanup, indent and remove of non 2.6 code by Alan Cox
13  *	<alan@lxorguk.ukuu.org.uk>. The original 1.8 code is available on
14  *	www.moxa.com.
15  *	- Fixed x86_64 cleanness
16  */
17 
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/signal.h>
21 #include <linux/sched.h>
22 #include <linux/timer.h>
23 #include <linux/interrupt.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/serial.h>
27 #include <linux/serial_reg.h>
28 #include <linux/major.h>
29 #include <linux/string.h>
30 #include <linux/fcntl.h>
31 #include <linux/ptrace.h>
32 #include <linux/ioport.h>
33 #include <linux/mm.h>
34 #include <linux/delay.h>
35 #include <linux/pci.h>
36 #include <linux/bitops.h>
37 #include <linux/slab.h>
38 #include <linux/ratelimit.h>
39 
40 #include <asm/io.h>
41 #include <asm/irq.h>
42 #include <linux/uaccess.h>
43 
44 /*
45  *	Semi-public control interfaces
46  */
47 
48 /*
49  *	MOXA ioctls
50  */
51 
52 #define MOXA			0x400
53 #define MOXA_SET_OP_MODE	(MOXA + 66)
54 #define MOXA_GET_OP_MODE	(MOXA + 67)
55 
56 #define RS232_MODE		0
57 #define RS485_2WIRE_MODE	1
58 #define RS422_MODE		2
59 #define RS485_4WIRE_MODE	3
60 #define OP_MODE_MASK		3
61 
62 /* --------------------------------------------------- */
63 
64 /*
65  * Follow just what Moxa Must chip defines.
66  *
67  * When LCR register (offset 0x03) is written the following value, the Must chip
68  * will enter enhanced mode. And a write to EFR (offset 0x02) bit 6,7 will
69  * change bank.
70  */
71 #define MOXA_MUST_ENTER_ENHANCED	0xBF
72 
73 /* when enhanced mode is enabled, access to general bank register */
74 #define MOXA_MUST_GDL_REGISTER		0x07
75 #define MOXA_MUST_GDL_MASK		0x7F
76 #define MOXA_MUST_GDL_HAS_BAD_DATA	0x80
77 
78 #define MOXA_MUST_LSR_RERR		0x80	/* error in receive FIFO */
79 /* enhanced register bank select and enhanced mode setting register */
80 /* This works only when LCR register equals to 0xBF */
81 #define MOXA_MUST_EFR_REGISTER		0x02
82 #define MOXA_MUST_EFR_EFRB_ENABLE	0x10 /* enhanced mode enable */
83 /* enhanced register bank set 0, 1, 2 */
84 #define MOXA_MUST_EFR_BANK0		0x00
85 #define MOXA_MUST_EFR_BANK1		0x40
86 #define MOXA_MUST_EFR_BANK2		0x80
87 #define MOXA_MUST_EFR_BANK3		0xC0
88 #define MOXA_MUST_EFR_BANK_MASK		0xC0
89 
90 /* set XON1 value register, when LCR=0xBF and change to bank0 */
91 #define MOXA_MUST_XON1_REGISTER		0x04
92 
93 /* set XON2 value register, when LCR=0xBF and change to bank0 */
94 #define MOXA_MUST_XON2_REGISTER		0x05
95 
96 /* set XOFF1 value register, when LCR=0xBF and change to bank0 */
97 #define MOXA_MUST_XOFF1_REGISTER	0x06
98 
99 /* set XOFF2 value register, when LCR=0xBF and change to bank0 */
100 #define MOXA_MUST_XOFF2_REGISTER	0x07
101 
102 #define MOXA_MUST_RBRTL_REGISTER	0x04
103 #define MOXA_MUST_RBRTH_REGISTER	0x05
104 #define MOXA_MUST_RBRTI_REGISTER	0x06
105 #define MOXA_MUST_THRTL_REGISTER	0x07
106 #define MOXA_MUST_ENUM_REGISTER		0x04
107 #define MOXA_MUST_HWID_REGISTER		0x05
108 #define MOXA_MUST_ECR_REGISTER		0x06
109 #define MOXA_MUST_CSR_REGISTER		0x07
110 
111 #define MOXA_MUST_FCR_GDA_MODE_ENABLE	0x20 /* good data mode enable */
112 #define MOXA_MUST_FCR_GDA_ONLY_ENABLE	0x10 /* only good data put into RxFIFO */
113 
114 #define MOXA_MUST_IER_ECTSI		0x80 /* enable CTS interrupt */
115 #define MOXA_MUST_IER_ERTSI		0x40 /* enable RTS interrupt */
116 #define MOXA_MUST_IER_XINT		0x20 /* enable Xon/Xoff interrupt */
117 #define MOXA_MUST_IER_EGDAI		0x10 /* enable GDA interrupt */
118 
119 #define MOXA_MUST_RECV_ISR		(UART_IER_RDI | MOXA_MUST_IER_EGDAI)
120 
121 /* GDA interrupt pending */
122 #define MOXA_MUST_IIR_GDA		0x1C
123 #define MOXA_MUST_IIR_RDA		0x04
124 #define MOXA_MUST_IIR_RTO		0x0C
125 #define MOXA_MUST_IIR_LSR		0x06
126 
127 /* received Xon/Xoff or specical interrupt pending */
128 #define MOXA_MUST_IIR_XSC		0x10
129 
130 /* RTS/CTS change state interrupt pending */
131 #define MOXA_MUST_IIR_RTSCTS		0x20
132 #define MOXA_MUST_IIR_MASK		0x3E
133 
134 #define MOXA_MUST_MCR_XON_FLAG		0x40
135 #define MOXA_MUST_MCR_XON_ANY		0x80
136 #define MOXA_MUST_MCR_TX_XON		0x08
137 
138 #define MOXA_MUST_EFR_SF_MASK		0x0F /* software flow control on chip mask value */
139 #define MOXA_MUST_EFR_SF_TX1		0x08 /* send Xon1/Xoff1 */
140 #define MOXA_MUST_EFR_SF_TX2		0x04 /* send Xon2/Xoff2 */
141 #define MOXA_MUST_EFR_SF_TX12		0x0C /* send Xon1,Xon2/Xoff1,Xoff2 */
142 #define MOXA_MUST_EFR_SF_TX_NO		0x00 /* don't send Xon/Xoff */
143 #define MOXA_MUST_EFR_SF_TX_MASK	0x0C /* Tx software flow control mask */
144 #define MOXA_MUST_EFR_SF_RX_NO		0x00 /* don't receive Xon/Xoff */
145 #define MOXA_MUST_EFR_SF_RX1		0x02 /* receive Xon1/Xoff1 */
146 #define MOXA_MUST_EFR_SF_RX2		0x01 /* receive Xon2/Xoff2 */
147 #define MOXA_MUST_EFR_SF_RX12		0x03 /* receive Xon1,Xon2/Xoff1,Xoff2 */
148 #define MOXA_MUST_EFR_SF_RX_MASK	0x03 /* Rx software flow control mask */
149 
150 #define	MXSERMAJOR	 174
151 
152 #define MXSER_BOARDS		4	/* Max. boards */
153 #define MXSER_PORTS_PER_BOARD	8	/* Max. ports per board */
154 #define MXSER_PORTS		(MXSER_BOARDS * MXSER_PORTS_PER_BOARD)
155 #define MXSER_ISR_PASS_LIMIT	100
156 
157 #define WAKEUP_CHARS		256
158 
159 #define MXSER_BAUD_BASE		921600
160 #define MXSER_CUSTOM_DIVISOR	(MXSER_BAUD_BASE * 16)
161 
162 #define PCI_DEVICE_ID_MOXA_RC7000	0x0001
163 #define PCI_DEVICE_ID_MOXA_CP102	0x1020
164 #define PCI_DEVICE_ID_MOXA_CP102UL	0x1021
165 #define PCI_DEVICE_ID_MOXA_CP102U	0x1022
166 #define PCI_DEVICE_ID_MOXA_CP102UF	0x1023
167 #define PCI_DEVICE_ID_MOXA_C104		0x1040
168 #define PCI_DEVICE_ID_MOXA_CP104U	0x1041
169 #define PCI_DEVICE_ID_MOXA_CP104JU	0x1042
170 #define PCI_DEVICE_ID_MOXA_CP104EL	0x1043
171 #define PCI_DEVICE_ID_MOXA_POS104UL	0x1044
172 #define PCI_DEVICE_ID_MOXA_CB108	0x1080
173 #define PCI_DEVICE_ID_MOXA_CP112UL	0x1120
174 #define PCI_DEVICE_ID_MOXA_CT114	0x1140
175 #define PCI_DEVICE_ID_MOXA_CP114	0x1141
176 #define PCI_DEVICE_ID_MOXA_CB114	0x1142
177 #define PCI_DEVICE_ID_MOXA_CP114UL	0x1143
178 #define PCI_DEVICE_ID_MOXA_CP118U	0x1180
179 #define PCI_DEVICE_ID_MOXA_CP118EL	0x1181
180 #define PCI_DEVICE_ID_MOXA_CP132	0x1320
181 #define PCI_DEVICE_ID_MOXA_CP132U	0x1321
182 #define PCI_DEVICE_ID_MOXA_CP134U	0x1340
183 #define PCI_DEVICE_ID_MOXA_CB134I	0x1341
184 #define PCI_DEVICE_ID_MOXA_CP138U	0x1380
185 #define PCI_DEVICE_ID_MOXA_C168		0x1680
186 #define PCI_DEVICE_ID_MOXA_CP168U	0x1681
187 #define PCI_DEVICE_ID_MOXA_CP168EL	0x1682
188 
189 #define MXSER_NPORTS(ddata)		((ddata) & 0xffU)
190 #define MXSER_HIGHBAUD			0x0100
191 
192 enum mxser_must_hwid {
193 	MOXA_OTHER_UART		= 0x00,
194 	MOXA_MUST_MU150_HWID	= 0x01,
195 	MOXA_MUST_MU860_HWID	= 0x02,
196 };
197 
198 static const struct {
199 	u8 type;
200 	u8 fifo_size;
201 	u8 rx_high_water;
202 	u8 rx_low_water;
203 	speed_t max_baud;
204 } Gpci_uart_info[] = {
205 	{ MOXA_OTHER_UART,	 16, 14,  1, 921600 },
206 	{ MOXA_MUST_MU150_HWID,	 64, 48, 16, 230400 },
207 	{ MOXA_MUST_MU860_HWID, 128, 96, 32, 921600 }
208 };
209 #define UART_INFO_NUM	ARRAY_SIZE(Gpci_uart_info)
210 
211 
212 /* driver_data correspond to the lines in the structure above
213    see also ISA probe function before you change something */
214 static const struct pci_device_id mxser_pcibrds[] = {
215 	{ PCI_DEVICE_DATA(MOXA, C168,		8) },
216 	{ PCI_DEVICE_DATA(MOXA, C104,		4) },
217 	{ PCI_DEVICE_DATA(MOXA, CP132,		2) },
218 	{ PCI_DEVICE_DATA(MOXA, CP114,		4) },
219 	{ PCI_DEVICE_DATA(MOXA, CT114,		4) },
220 	{ PCI_DEVICE_DATA(MOXA, CP102,		2 | MXSER_HIGHBAUD) },
221 	{ PCI_DEVICE_DATA(MOXA, CP104U,		4) },
222 	{ PCI_DEVICE_DATA(MOXA, CP168U,		8) },
223 	{ PCI_DEVICE_DATA(MOXA, CP132U,		2) },
224 	{ PCI_DEVICE_DATA(MOXA, CP134U,		4) },
225 	{ PCI_DEVICE_DATA(MOXA, CP104JU,	4) },
226 	{ PCI_DEVICE_DATA(MOXA, RC7000,		8) }, /* RC7000 */
227 	{ PCI_DEVICE_DATA(MOXA, CP118U,		8) },
228 	{ PCI_DEVICE_DATA(MOXA, CP102UL,	2) },
229 	{ PCI_DEVICE_DATA(MOXA, CP102U,		2) },
230 	{ PCI_DEVICE_DATA(MOXA, CP118EL,	8) },
231 	{ PCI_DEVICE_DATA(MOXA, CP168EL,	8) },
232 	{ PCI_DEVICE_DATA(MOXA, CP104EL,	4) },
233 	{ PCI_DEVICE_DATA(MOXA, CB108,		8) },
234 	{ PCI_DEVICE_DATA(MOXA, CB114,		4) },
235 	{ PCI_DEVICE_DATA(MOXA, CB134I,		4) },
236 	{ PCI_DEVICE_DATA(MOXA, CP138U,		8) },
237 	{ PCI_DEVICE_DATA(MOXA, POS104UL,	4) },
238 	{ PCI_DEVICE_DATA(MOXA, CP114UL,	4) },
239 	{ PCI_DEVICE_DATA(MOXA, CP102UF,	2) },
240 	{ PCI_DEVICE_DATA(MOXA, CP112UL,	2) },
241 	{ }
242 };
243 MODULE_DEVICE_TABLE(pci, mxser_pcibrds);
244 
245 static int ttymajor = MXSERMAJOR;
246 
247 /* Variables for insmod */
248 
249 MODULE_AUTHOR("Casper Yang");
250 MODULE_DESCRIPTION("MOXA Smartio/Industio Family Multiport Board Device Driver");
251 module_param(ttymajor, int, 0);
252 MODULE_LICENSE("GPL");
253 
254 struct mxser_board;
255 
256 struct mxser_port {
257 	struct tty_port port;
258 	struct mxser_board *board;
259 
260 	unsigned long ioaddr;
261 	unsigned long opmode_ioaddr;
262 
263 	u8 rx_high_water;
264 	u8 rx_low_water;
265 	int type;		/* UART type */
266 
267 	unsigned char x_char;	/* xon/xoff character */
268 	u8 IER;			/* Interrupt Enable Register */
269 	u8 MCR;			/* Modem control register */
270 	u8 FCR;			/* FIFO control register */
271 
272 	struct async_icount icount; /* kernel counters for 4 input interrupts */
273 	unsigned int timeout;
274 
275 	u8 read_status_mask;
276 	u8 ignore_status_mask;
277 	u8 xmit_fifo_size;
278 
279 	spinlock_t slock;
280 };
281 
282 struct mxser_board {
283 	unsigned int idx;
284 	unsigned short nports;
285 	int irq;
286 	unsigned long vector;
287 
288 	enum mxser_must_hwid must_hwid;
289 	speed_t max_baud;
290 
291 	struct mxser_port ports[];
292 };
293 
294 static DECLARE_BITMAP(mxser_boards, MXSER_BOARDS);
295 static struct tty_driver *mxvar_sdriver;
296 
297 static u8 __mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set,
298 		bool restore_LCR)
299 {
300 	u8 oldlcr, efr;
301 
302 	oldlcr = inb(baseio + UART_LCR);
303 	outb(MOXA_MUST_ENTER_ENHANCED, baseio + UART_LCR);
304 
305 	efr = inb(baseio + MOXA_MUST_EFR_REGISTER);
306 	efr &= ~clear;
307 	efr |= set;
308 
309 	outb(efr, baseio + MOXA_MUST_EFR_REGISTER);
310 
311 	if (restore_LCR)
312 		outb(oldlcr, baseio + UART_LCR);
313 
314 	return oldlcr;
315 }
316 
317 static u8 mxser_must_select_bank(unsigned long baseio, u8 bank)
318 {
319 	return __mxser_must_set_EFR(baseio, MOXA_MUST_EFR_BANK_MASK, bank,
320 			false);
321 }
322 
323 static void mxser_set_must_xon1_value(unsigned long baseio, u8 value)
324 {
325 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
326 	outb(value, baseio + MOXA_MUST_XON1_REGISTER);
327 	outb(oldlcr, baseio + UART_LCR);
328 }
329 
330 static void mxser_set_must_xoff1_value(unsigned long baseio, u8 value)
331 {
332 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
333 	outb(value, baseio + MOXA_MUST_XOFF1_REGISTER);
334 	outb(oldlcr, baseio + UART_LCR);
335 }
336 
337 static void mxser_set_must_fifo_value(struct mxser_port *info)
338 {
339 	u8 oldlcr = mxser_must_select_bank(info->ioaddr, MOXA_MUST_EFR_BANK1);
340 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTH_REGISTER);
341 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTI_REGISTER);
342 	outb(info->rx_low_water, info->ioaddr + MOXA_MUST_RBRTL_REGISTER);
343 	outb(oldlcr, info->ioaddr + UART_LCR);
344 }
345 
346 static void mxser_set_must_enum_value(unsigned long baseio, u8 value)
347 {
348 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
349 	outb(value, baseio + MOXA_MUST_ENUM_REGISTER);
350 	outb(oldlcr, baseio + UART_LCR);
351 }
352 
353 static u8 mxser_get_must_hardware_id(unsigned long baseio)
354 {
355 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
356 	u8 id = inb(baseio + MOXA_MUST_HWID_REGISTER);
357 	outb(oldlcr, baseio + UART_LCR);
358 
359 	return id;
360 }
361 
362 static void mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set)
363 {
364 	__mxser_must_set_EFR(baseio, clear, set, true);
365 }
366 
367 static void mxser_must_set_enhance_mode(unsigned long baseio, bool enable)
368 {
369 	mxser_must_set_EFR(baseio,
370 			enable ? 0 : MOXA_MUST_EFR_EFRB_ENABLE,
371 			enable ? MOXA_MUST_EFR_EFRB_ENABLE : 0);
372 }
373 
374 static void mxser_must_no_sw_flow_control(unsigned long baseio)
375 {
376 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_MASK, 0);
377 }
378 
379 static void mxser_must_set_tx_sw_flow_control(unsigned long baseio, bool enable)
380 {
381 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_TX_MASK,
382 			enable ? MOXA_MUST_EFR_SF_TX1 : 0);
383 }
384 
385 static void mxser_must_set_rx_sw_flow_control(unsigned long baseio, bool enable)
386 {
387 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_RX_MASK,
388 			enable ? MOXA_MUST_EFR_SF_RX1 : 0);
389 }
390 
391 static enum mxser_must_hwid mxser_must_get_hwid(unsigned long io)
392 {
393 	u8 oldmcr, hwid;
394 	int i;
395 
396 	outb(0, io + UART_LCR);
397 	mxser_must_set_enhance_mode(io, false);
398 	oldmcr = inb(io + UART_MCR);
399 	outb(0, io + UART_MCR);
400 	mxser_set_must_xon1_value(io, 0x11);
401 	if (inb(io + UART_MCR) != 0) {
402 		outb(oldmcr, io + UART_MCR);
403 		return MOXA_OTHER_UART;
404 	}
405 
406 	hwid = mxser_get_must_hardware_id(io);
407 	for (i = 1; i < UART_INFO_NUM; i++) /* 0 = OTHER_UART */
408 		if (hwid == Gpci_uart_info[i].type)
409 			return hwid;
410 
411 	return MOXA_OTHER_UART;
412 }
413 
414 static bool mxser_16550A_or_MUST(struct mxser_port *info)
415 {
416 	return info->type == PORT_16550A || info->board->must_hwid;
417 }
418 
419 static void mxser_process_txrx_fifo(struct mxser_port *info)
420 {
421 	unsigned int i;
422 
423 	if (info->type == PORT_16450 || info->type == PORT_8250) {
424 		info->rx_high_water = 1;
425 		info->rx_low_water = 1;
426 		info->xmit_fifo_size = 1;
427 		return;
428 	}
429 
430 	for (i = 0; i < UART_INFO_NUM; i++)
431 		if (info->board->must_hwid == Gpci_uart_info[i].type) {
432 			info->rx_low_water = Gpci_uart_info[i].rx_low_water;
433 			info->rx_high_water = Gpci_uart_info[i].rx_high_water;
434 			info->xmit_fifo_size = Gpci_uart_info[i].fifo_size;
435 			break;
436 		}
437 }
438 
439 static void __mxser_start_tx(struct mxser_port *info)
440 {
441 	outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);
442 	info->IER |= UART_IER_THRI;
443 	outb(info->IER, info->ioaddr + UART_IER);
444 }
445 
446 static void mxser_start_tx(struct mxser_port *info)
447 {
448 	unsigned long flags;
449 
450 	spin_lock_irqsave(&info->slock, flags);
451 	__mxser_start_tx(info);
452 	spin_unlock_irqrestore(&info->slock, flags);
453 }
454 
455 static void __mxser_stop_tx(struct mxser_port *info)
456 {
457 	info->IER &= ~UART_IER_THRI;
458 	outb(info->IER, info->ioaddr + UART_IER);
459 }
460 
461 static bool mxser_carrier_raised(struct tty_port *port)
462 {
463 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
464 
465 	return inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD;
466 }
467 
468 static void mxser_dtr_rts(struct tty_port *port, bool active)
469 {
470 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
471 	unsigned long flags;
472 	u8 mcr;
473 
474 	spin_lock_irqsave(&mp->slock, flags);
475 	mcr = inb(mp->ioaddr + UART_MCR);
476 	if (active)
477 		mcr |= UART_MCR_DTR | UART_MCR_RTS;
478 	else
479 		mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
480 	outb(mcr, mp->ioaddr + UART_MCR);
481 	spin_unlock_irqrestore(&mp->slock, flags);
482 }
483 
484 static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
485 {
486 	struct mxser_port *info = tty->driver_data;
487 	unsigned int quot = 0, baud;
488 	unsigned char cval;
489 	u64 timeout;
490 
491 	if (newspd > info->board->max_baud)
492 		return -1;
493 
494 	if (newspd == 134) {
495 		quot = 2 * MXSER_BAUD_BASE / 269;
496 		tty_encode_baud_rate(tty, 134, 134);
497 	} else if (newspd) {
498 		quot = MXSER_BAUD_BASE / newspd;
499 		if (quot == 0)
500 			quot = 1;
501 		baud = MXSER_BAUD_BASE / quot;
502 		tty_encode_baud_rate(tty, baud, baud);
503 	} else {
504 		quot = 0;
505 	}
506 
507 	/*
508 	 * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the
509 	 * u64 domain
510 	 */
511 	timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot;
512 	do_div(timeout, MXSER_BAUD_BASE);
513 	info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */
514 
515 	if (quot) {
516 		info->MCR |= UART_MCR_DTR;
517 		outb(info->MCR, info->ioaddr + UART_MCR);
518 	} else {
519 		info->MCR &= ~UART_MCR_DTR;
520 		outb(info->MCR, info->ioaddr + UART_MCR);
521 		return 0;
522 	}
523 
524 	cval = inb(info->ioaddr + UART_LCR);
525 
526 	outb(cval | UART_LCR_DLAB, info->ioaddr + UART_LCR);	/* set DLAB */
527 
528 	outb(quot & 0xff, info->ioaddr + UART_DLL);	/* LS of divisor */
529 	outb(quot >> 8, info->ioaddr + UART_DLM);	/* MS of divisor */
530 	outb(cval, info->ioaddr + UART_LCR);	/* reset DLAB */
531 
532 	if (C_BAUD(tty) == BOTHER) {
533 		quot = MXSER_BAUD_BASE % newspd;
534 		quot *= 8;
535 		if (quot % newspd > newspd / 2) {
536 			quot /= newspd;
537 			quot++;
538 		} else
539 			quot /= newspd;
540 
541 		mxser_set_must_enum_value(info->ioaddr, quot);
542 	} else {
543 		mxser_set_must_enum_value(info->ioaddr, 0);
544 	}
545 
546 	return 0;
547 }
548 
549 static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
550 		u8 msr)
551 {
552 	bool cts = msr & UART_MSR_CTS;
553 
554 	if (tty->hw_stopped) {
555 		if (cts) {
556 			tty->hw_stopped = false;
557 
558 			if (!mxser_16550A_or_MUST(info))
559 				__mxser_start_tx(info);
560 			tty_wakeup(tty);
561 		}
562 		return;
563 	} else if (cts)
564 		return;
565 
566 	tty->hw_stopped = true;
567 	if (!mxser_16550A_or_MUST(info))
568 		__mxser_stop_tx(info);
569 }
570 
571 /*
572  * This routine is called to set the UART divisor registers to match
573  * the specified baud rate for a serial port.
574  */
575 static void mxser_change_speed(struct tty_struct *tty,
576 			       const struct ktermios *old_termios)
577 {
578 	struct mxser_port *info = tty->driver_data;
579 	unsigned cflag, cval;
580 
581 	cflag = tty->termios.c_cflag;
582 
583 	if (mxser_set_baud(tty, tty_get_baud_rate(tty))) {
584 		/* Use previous rate on a failure */
585 		if (old_termios) {
586 			speed_t baud = tty_termios_baud_rate(old_termios);
587 			tty_encode_baud_rate(tty, baud, baud);
588 		}
589 	}
590 
591 	/* byte size and parity */
592 	cval = UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
593 
594 	if (cflag & CSTOPB)
595 		cval |= UART_LCR_STOP;
596 	if (cflag & PARENB)
597 		cval |= UART_LCR_PARITY;
598 	if (!(cflag & PARODD))
599 		cval |= UART_LCR_EPAR;
600 	if (cflag & CMSPAR)
601 		cval |= UART_LCR_SPAR;
602 
603 	info->FCR = 0;
604 	if (info->board->must_hwid) {
605 		info->FCR |= UART_FCR_ENABLE_FIFO |
606 			MOXA_MUST_FCR_GDA_MODE_ENABLE;
607 		mxser_set_must_fifo_value(info);
608 	} else if (info->type != PORT_8250 && info->type != PORT_16450) {
609 		info->FCR |= UART_FCR_ENABLE_FIFO;
610 		switch (info->rx_high_water) {
611 		case 1:
612 			info->FCR |= UART_FCR_TRIGGER_1;
613 			break;
614 		case 4:
615 			info->FCR |= UART_FCR_TRIGGER_4;
616 			break;
617 		case 8:
618 			info->FCR |= UART_FCR_TRIGGER_8;
619 			break;
620 		default:
621 			info->FCR |= UART_FCR_TRIGGER_14;
622 			break;
623 		}
624 	}
625 
626 	/* CTS flow control flag and modem status interrupts */
627 	info->IER &= ~UART_IER_MSI;
628 	info->MCR &= ~UART_MCR_AFE;
629 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
630 	if (cflag & CRTSCTS) {
631 		info->IER |= UART_IER_MSI;
632 		if (mxser_16550A_or_MUST(info)) {
633 			info->MCR |= UART_MCR_AFE;
634 		} else {
635 			mxser_handle_cts(tty, info,
636 					inb(info->ioaddr + UART_MSR));
637 		}
638 	}
639 	outb(info->MCR, info->ioaddr + UART_MCR);
640 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
641 	if (~cflag & CLOCAL)
642 		info->IER |= UART_IER_MSI;
643 	outb(info->IER, info->ioaddr + UART_IER);
644 
645 	/*
646 	 * Set up parity check flag
647 	 */
648 	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
649 	if (I_INPCK(tty))
650 		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
651 	if (I_BRKINT(tty) || I_PARMRK(tty))
652 		info->read_status_mask |= UART_LSR_BI;
653 
654 	info->ignore_status_mask = 0;
655 
656 	if (I_IGNBRK(tty)) {
657 		info->ignore_status_mask |= UART_LSR_BI;
658 		info->read_status_mask |= UART_LSR_BI;
659 		/*
660 		 * If we're ignore parity and break indicators, ignore
661 		 * overruns too.  (For real raw support).
662 		 */
663 		if (I_IGNPAR(tty)) {
664 			info->ignore_status_mask |=
665 						UART_LSR_OE |
666 						UART_LSR_PE |
667 						UART_LSR_FE;
668 			info->read_status_mask |=
669 						UART_LSR_OE |
670 						UART_LSR_PE |
671 						UART_LSR_FE;
672 		}
673 	}
674 	if (info->board->must_hwid) {
675 		mxser_set_must_xon1_value(info->ioaddr, START_CHAR(tty));
676 		mxser_set_must_xoff1_value(info->ioaddr, STOP_CHAR(tty));
677 		mxser_must_set_rx_sw_flow_control(info->ioaddr, I_IXON(tty));
678 		mxser_must_set_tx_sw_flow_control(info->ioaddr, I_IXOFF(tty));
679 	}
680 
681 
682 	outb(info->FCR, info->ioaddr + UART_FCR);
683 	outb(cval, info->ioaddr + UART_LCR);
684 }
685 
686 static u8 mxser_check_modem_status(struct tty_struct *tty,
687 				struct mxser_port *port)
688 {
689 	u8 msr = inb(port->ioaddr + UART_MSR);
690 
691 	if (!(msr & UART_MSR_ANY_DELTA))
692 		return msr;
693 
694 	/* update input line counters */
695 	if (msr & UART_MSR_TERI)
696 		port->icount.rng++;
697 	if (msr & UART_MSR_DDSR)
698 		port->icount.dsr++;
699 	if (msr & UART_MSR_DDCD)
700 		port->icount.dcd++;
701 	if (msr & UART_MSR_DCTS)
702 		port->icount.cts++;
703 	wake_up_interruptible(&port->port.delta_msr_wait);
704 
705 	if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) {
706 		if (msr & UART_MSR_DCD)
707 			wake_up_interruptible(&port->port.open_wait);
708 	}
709 
710 	if (tty_port_cts_enabled(&port->port))
711 		mxser_handle_cts(tty, port, msr);
712 
713 	return msr;
714 }
715 
716 static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
717 {
718 	u8 fcr = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
719 
720 	if (info->board->must_hwid)
721 		fcr |= MOXA_MUST_FCR_GDA_MODE_ENABLE;
722 
723 	outb(fcr, info->ioaddr + UART_FCR);
724 }
725 
726 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
727 {
728 	struct mxser_port *info = container_of(port, struct mxser_port, port);
729 	unsigned long flags;
730 	int ret;
731 
732 	ret = tty_port_alloc_xmit_buf(port);
733 	if (ret < 0)
734 		return ret;
735 
736 	spin_lock_irqsave(&info->slock, flags);
737 
738 	if (!info->type) {
739 		set_bit(TTY_IO_ERROR, &tty->flags);
740 		spin_unlock_irqrestore(&info->slock, flags);
741 		ret = 0;
742 		goto err_free_xmit;
743 	}
744 
745 	/*
746 	 * Clear the FIFO buffers and disable them
747 	 * (they will be reenabled in mxser_change_speed())
748 	 */
749 	mxser_disable_and_clear_FIFO(info);
750 
751 	/*
752 	 * At this point there's no way the LSR could still be 0xFF;
753 	 * if it is, then bail out, because there's likely no UART
754 	 * here.
755 	 */
756 	if (inb(info->ioaddr + UART_LSR) == 0xff) {
757 		spin_unlock_irqrestore(&info->slock, flags);
758 		if (capable(CAP_SYS_ADMIN)) {
759 			set_bit(TTY_IO_ERROR, &tty->flags);
760 			return 0;
761 		}
762 
763 		ret = -ENODEV;
764 		goto err_free_xmit;
765 	}
766 
767 	/*
768 	 * Clear the interrupt registers.
769 	 */
770 	(void) inb(info->ioaddr + UART_LSR);
771 	(void) inb(info->ioaddr + UART_RX);
772 	(void) inb(info->ioaddr + UART_IIR);
773 	(void) inb(info->ioaddr + UART_MSR);
774 
775 	/*
776 	 * Now, initialize the UART
777 	 */
778 	outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR);	/* reset DLAB */
779 	info->MCR = UART_MCR_DTR | UART_MCR_RTS;
780 	outb(info->MCR, info->ioaddr + UART_MCR);
781 
782 	/*
783 	 * Finally, enable interrupts
784 	 */
785 	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
786 
787 	if (info->board->must_hwid)
788 		info->IER |= MOXA_MUST_IER_EGDAI;
789 	outb(info->IER, info->ioaddr + UART_IER);	/* enable interrupts */
790 
791 	/*
792 	 * And clear the interrupt registers again for luck.
793 	 */
794 	(void) inb(info->ioaddr + UART_LSR);
795 	(void) inb(info->ioaddr + UART_RX);
796 	(void) inb(info->ioaddr + UART_IIR);
797 	(void) inb(info->ioaddr + UART_MSR);
798 
799 	clear_bit(TTY_IO_ERROR, &tty->flags);
800 	kfifo_reset(&port->xmit_fifo);
801 
802 	/*
803 	 * and set the speed of the serial port
804 	 */
805 	mxser_change_speed(tty, NULL);
806 	spin_unlock_irqrestore(&info->slock, flags);
807 
808 	return 0;
809 err_free_xmit:
810 	tty_port_free_xmit_buf(port);
811 	return ret;
812 }
813 
814 /*
815  * To stop accepting input, we disable the receive line status interrupts, and
816  * tell the interrupt driver to stop checking the data ready bit in the line
817  * status register.
818  */
819 static void mxser_stop_rx(struct mxser_port *info)
820 {
821 	info->IER &= ~UART_IER_RLSI;
822 	if (info->board->must_hwid)
823 		info->IER &= ~MOXA_MUST_RECV_ISR;
824 
825 	outb(info->IER, info->ioaddr + UART_IER);
826 }
827 
828 /*
829  * This routine will shutdown a serial port
830  */
831 static void mxser_shutdown_port(struct tty_port *port)
832 {
833 	struct mxser_port *info = container_of(port, struct mxser_port, port);
834 	unsigned long flags;
835 
836 	spin_lock_irqsave(&info->slock, flags);
837 
838 	mxser_stop_rx(info);
839 
840 	/*
841 	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
842 	 * here so the queue might never be waken up
843 	 */
844 	wake_up_interruptible(&info->port.delta_msr_wait);
845 
846 	info->IER = 0;
847 	outb(0x00, info->ioaddr + UART_IER);
848 
849 	/* clear Rx/Tx FIFO's */
850 	mxser_disable_and_clear_FIFO(info);
851 
852 	/* read data port to reset things */
853 	(void) inb(info->ioaddr + UART_RX);
854 
855 
856 	if (info->board->must_hwid)
857 		mxser_must_no_sw_flow_control(info->ioaddr);
858 
859 	spin_unlock_irqrestore(&info->slock, flags);
860 
861 	/* make sure ISR is not running while we free the buffer */
862 	synchronize_irq(info->board->irq);
863 
864 	tty_port_free_xmit_buf(port);
865 }
866 
867 /*
868  * This routine is called whenever a serial port is opened.  It
869  * enables interrupts for a serial port, linking in its async structure into
870  * the IRQ chain.   It also performs the serial-specific
871  * initialization for the tty structure.
872  */
873 static int mxser_open(struct tty_struct *tty, struct file *filp)
874 {
875 	struct tty_port *tport = tty->port;
876 	struct mxser_port *port = container_of(tport, struct mxser_port, port);
877 
878 	tty->driver_data = port;
879 
880 	return tty_port_open(tport, tty, filp);
881 }
882 
883 static void mxser_flush_buffer(struct tty_struct *tty)
884 {
885 	struct mxser_port *info = tty->driver_data;
886 	unsigned long flags;
887 
888 	spin_lock_irqsave(&info->slock, flags);
889 	kfifo_reset(&info->port.xmit_fifo);
890 
891 	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
892 		info->ioaddr + UART_FCR);
893 
894 	spin_unlock_irqrestore(&info->slock, flags);
895 
896 	tty_wakeup(tty);
897 }
898 
899 static void mxser_close(struct tty_struct *tty, struct file *filp)
900 {
901 	tty_port_close(tty->port, tty, filp);
902 }
903 
904 static int mxser_write(struct tty_struct *tty, const unsigned char *buf, int count)
905 {
906 	struct mxser_port *info = tty->driver_data;
907 	unsigned long flags;
908 	int written;
909 	bool is_empty;
910 
911 	spin_lock_irqsave(&info->slock, flags);
912 	written = kfifo_in(&info->port.xmit_fifo, buf, count);
913 	is_empty = kfifo_is_empty(&info->port.xmit_fifo);
914 	spin_unlock_irqrestore(&info->slock, flags);
915 
916 	if (!is_empty && !tty->flow.stopped)
917 		if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
918 			mxser_start_tx(info);
919 
920 	return written;
921 }
922 
923 static int mxser_put_char(struct tty_struct *tty, unsigned char ch)
924 {
925 	struct mxser_port *info = tty->driver_data;
926 	unsigned long flags;
927 	int ret;
928 
929 	spin_lock_irqsave(&info->slock, flags);
930 	ret = kfifo_put(&info->port.xmit_fifo, ch);
931 	spin_unlock_irqrestore(&info->slock, flags);
932 
933 	return ret;
934 }
935 
936 
937 static void mxser_flush_chars(struct tty_struct *tty)
938 {
939 	struct mxser_port *info = tty->driver_data;
940 
941 	if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped ||
942 			(tty->hw_stopped && !mxser_16550A_or_MUST(info)))
943 		return;
944 
945 	mxser_start_tx(info);
946 }
947 
948 static unsigned int mxser_write_room(struct tty_struct *tty)
949 {
950 	struct mxser_port *info = tty->driver_data;
951 
952 	return kfifo_avail(&info->port.xmit_fifo);
953 }
954 
955 static unsigned int mxser_chars_in_buffer(struct tty_struct *tty)
956 {
957 	struct mxser_port *info = tty->driver_data;
958 
959 	return kfifo_len(&info->port.xmit_fifo);
960 }
961 
962 /*
963  * ------------------------------------------------------------
964  * friends of mxser_ioctl()
965  * ------------------------------------------------------------
966  */
967 static int mxser_get_serial_info(struct tty_struct *tty,
968 		struct serial_struct *ss)
969 {
970 	struct mxser_port *info = tty->driver_data;
971 	struct tty_port *port = &info->port;
972 	unsigned int closing_wait, close_delay;
973 
974 	mutex_lock(&port->mutex);
975 
976 	close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
977 	closing_wait = info->port.closing_wait;
978 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
979 		closing_wait = jiffies_to_msecs(closing_wait) / 10;
980 
981 	ss->type = info->type;
982 	ss->line = tty->index;
983 	ss->port = info->ioaddr;
984 	ss->irq = info->board->irq;
985 	ss->flags = info->port.flags;
986 	ss->baud_base = MXSER_BAUD_BASE;
987 	ss->close_delay = close_delay;
988 	ss->closing_wait = closing_wait;
989 	ss->custom_divisor = MXSER_CUSTOM_DIVISOR,
990 	mutex_unlock(&port->mutex);
991 	return 0;
992 }
993 
994 static int mxser_set_serial_info(struct tty_struct *tty,
995 		struct serial_struct *ss)
996 {
997 	struct mxser_port *info = tty->driver_data;
998 	struct tty_port *port = &info->port;
999 	speed_t baud;
1000 	unsigned long sl_flags;
1001 	unsigned int old_speed, close_delay, closing_wait;
1002 	int retval = 0;
1003 
1004 	if (tty_io_error(tty))
1005 		return -EIO;
1006 
1007 	mutex_lock(&port->mutex);
1008 
1009 	if (ss->irq != info->board->irq ||
1010 			ss->port != info->ioaddr) {
1011 		mutex_unlock(&port->mutex);
1012 		return -EINVAL;
1013 	}
1014 
1015 	old_speed = port->flags & ASYNC_SPD_MASK;
1016 
1017 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
1018 	closing_wait = ss->closing_wait;
1019 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
1020 		closing_wait = msecs_to_jiffies(closing_wait * 10);
1021 
1022 	if (!capable(CAP_SYS_ADMIN)) {
1023 		if ((ss->baud_base != MXSER_BAUD_BASE) ||
1024 				(close_delay != port->close_delay) ||
1025 				(closing_wait != port->closing_wait) ||
1026 				((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) {
1027 			mutex_unlock(&port->mutex);
1028 			return -EPERM;
1029 		}
1030 		port->flags = (port->flags & ~ASYNC_USR_MASK) |
1031 				(ss->flags & ASYNC_USR_MASK);
1032 	} else {
1033 		/*
1034 		 * OK, past this point, all the error checking has been done.
1035 		 * At this point, we start making changes.....
1036 		 */
1037 		port->flags = ((port->flags & ~ASYNC_FLAGS) |
1038 				(ss->flags & ASYNC_FLAGS));
1039 		port->close_delay = close_delay;
1040 		port->closing_wait = closing_wait;
1041 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
1042 				(ss->baud_base != MXSER_BAUD_BASE ||
1043 				ss->custom_divisor !=
1044 				MXSER_CUSTOM_DIVISOR)) {
1045 			if (ss->custom_divisor == 0) {
1046 				mutex_unlock(&port->mutex);
1047 				return -EINVAL;
1048 			}
1049 			baud = ss->baud_base / ss->custom_divisor;
1050 			tty_encode_baud_rate(tty, baud, baud);
1051 		}
1052 
1053 		info->type = ss->type;
1054 
1055 		mxser_process_txrx_fifo(info);
1056 	}
1057 
1058 	if (tty_port_initialized(port)) {
1059 		if (old_speed != (port->flags & ASYNC_SPD_MASK)) {
1060 			spin_lock_irqsave(&info->slock, sl_flags);
1061 			mxser_change_speed(tty, NULL);
1062 			spin_unlock_irqrestore(&info->slock, sl_flags);
1063 		}
1064 	} else {
1065 		retval = mxser_activate(port, tty);
1066 		if (retval == 0)
1067 			tty_port_set_initialized(port, true);
1068 	}
1069 	mutex_unlock(&port->mutex);
1070 	return retval;
1071 }
1072 
1073 /*
1074  * mxser_get_lsr_info - get line status register info
1075  *
1076  * Purpose: Let user call ioctl() to get info when the UART physically
1077  *	    is emptied.  On bus types like RS485, the transmitter must
1078  *	    release the bus after transmitting. This must be done when
1079  *	    the transmit shift register is empty, not be done when the
1080  *	    transmit holding register is empty.  This functionality
1081  *	    allows an RS485 driver to be written in user space.
1082  */
1083 static int mxser_get_lsr_info(struct mxser_port *info,
1084 		unsigned int __user *value)
1085 {
1086 	unsigned char status;
1087 	unsigned int result;
1088 	unsigned long flags;
1089 
1090 	spin_lock_irqsave(&info->slock, flags);
1091 	status = inb(info->ioaddr + UART_LSR);
1092 	spin_unlock_irqrestore(&info->slock, flags);
1093 	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1094 	return put_user(result, value);
1095 }
1096 
1097 static int mxser_tiocmget(struct tty_struct *tty)
1098 {
1099 	struct mxser_port *info = tty->driver_data;
1100 	unsigned char control;
1101 	unsigned long flags;
1102 	u8 msr;
1103 
1104 	if (tty_io_error(tty))
1105 		return -EIO;
1106 
1107 	spin_lock_irqsave(&info->slock, flags);
1108 	control = info->MCR;
1109 	msr = mxser_check_modem_status(tty, info);
1110 	spin_unlock_irqrestore(&info->slock, flags);
1111 
1112 	return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
1113 		    ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
1114 		    ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |
1115 		    ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) |
1116 		    ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) |
1117 		    ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0);
1118 }
1119 
1120 static int mxser_tiocmset(struct tty_struct *tty,
1121 		unsigned int set, unsigned int clear)
1122 {
1123 	struct mxser_port *info = tty->driver_data;
1124 	unsigned long flags;
1125 
1126 	if (tty_io_error(tty))
1127 		return -EIO;
1128 
1129 	spin_lock_irqsave(&info->slock, flags);
1130 
1131 	if (set & TIOCM_RTS)
1132 		info->MCR |= UART_MCR_RTS;
1133 	if (set & TIOCM_DTR)
1134 		info->MCR |= UART_MCR_DTR;
1135 
1136 	if (clear & TIOCM_RTS)
1137 		info->MCR &= ~UART_MCR_RTS;
1138 	if (clear & TIOCM_DTR)
1139 		info->MCR &= ~UART_MCR_DTR;
1140 
1141 	outb(info->MCR, info->ioaddr + UART_MCR);
1142 	spin_unlock_irqrestore(&info->slock, flags);
1143 	return 0;
1144 }
1145 
1146 static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg,
1147 		struct async_icount *cprev)
1148 {
1149 	struct async_icount cnow;
1150 	unsigned long flags;
1151 	int ret;
1152 
1153 	spin_lock_irqsave(&info->slock, flags);
1154 	cnow = info->icount;	/* atomic copy */
1155 	spin_unlock_irqrestore(&info->slock, flags);
1156 
1157 	ret =	((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
1158 		((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
1159 		((arg & TIOCM_CD)  && (cnow.dcd != cprev->dcd)) ||
1160 		((arg & TIOCM_CTS) && (cnow.cts != cprev->cts));
1161 
1162 	*cprev = cnow;
1163 
1164 	return ret;
1165 }
1166 
1167 /* We should likely switch to TIOCGRS485/TIOCSRS485. */
1168 static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set,
1169 		int __user *u_opmode)
1170 {
1171 	int opmode, p = index % 4;
1172 	int shiftbit = p * 2;
1173 	u8 val;
1174 
1175 	if (port->board->must_hwid != MOXA_MUST_MU860_HWID)
1176 		return -EFAULT;
1177 
1178 	if (set) {
1179 		if (get_user(opmode, u_opmode))
1180 			return -EFAULT;
1181 
1182 		if (opmode & ~OP_MODE_MASK)
1183 			return -EINVAL;
1184 
1185 		spin_lock_irq(&port->slock);
1186 		val = inb(port->opmode_ioaddr);
1187 		val &= ~(OP_MODE_MASK << shiftbit);
1188 		val |= (opmode << shiftbit);
1189 		outb(val, port->opmode_ioaddr);
1190 		spin_unlock_irq(&port->slock);
1191 
1192 		return 0;
1193 	}
1194 
1195 	spin_lock_irq(&port->slock);
1196 	opmode = inb(port->opmode_ioaddr) >> shiftbit;
1197 	spin_unlock_irq(&port->slock);
1198 
1199 	return put_user(opmode & OP_MODE_MASK, u_opmode);
1200 }
1201 
1202 static int mxser_ioctl(struct tty_struct *tty,
1203 		unsigned int cmd, unsigned long arg)
1204 {
1205 	struct mxser_port *info = tty->driver_data;
1206 	struct async_icount cnow;
1207 	unsigned long flags;
1208 	void __user *argp = (void __user *)arg;
1209 
1210 	if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE)
1211 		return mxser_ioctl_op_mode(info, tty->index,
1212 				cmd == MOXA_SET_OP_MODE, argp);
1213 
1214 	if (cmd != TIOCMIWAIT && tty_io_error(tty))
1215 		return -EIO;
1216 
1217 	switch (cmd) {
1218 	case TIOCSERGETLSR:	/* Get line status register */
1219 		return  mxser_get_lsr_info(info, argp);
1220 		/*
1221 		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1222 		 * - mask passed in arg for lines of interest
1223 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1224 		 * Caller should use TIOCGICOUNT to see which one it was
1225 		 */
1226 	case TIOCMIWAIT:
1227 		spin_lock_irqsave(&info->slock, flags);
1228 		cnow = info->icount;	/* note the counters on entry */
1229 		spin_unlock_irqrestore(&info->slock, flags);
1230 
1231 		return wait_event_interruptible(info->port.delta_msr_wait,
1232 				mxser_cflags_changed(info, arg, &cnow));
1233 	default:
1234 		return -ENOIOCTLCMD;
1235 	}
1236 	return 0;
1237 }
1238 
1239 	/*
1240 	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1241 	 * Return: write counters to the user passed counter struct
1242 	 * NB: both 1->0 and 0->1 transitions are counted except for
1243 	 *     RI where only 0->1 is counted.
1244 	 */
1245 
1246 static int mxser_get_icount(struct tty_struct *tty,
1247 		struct serial_icounter_struct *icount)
1248 
1249 {
1250 	struct mxser_port *info = tty->driver_data;
1251 	struct async_icount cnow;
1252 	unsigned long flags;
1253 
1254 	spin_lock_irqsave(&info->slock, flags);
1255 	cnow = info->icount;
1256 	spin_unlock_irqrestore(&info->slock, flags);
1257 
1258 	icount->frame = cnow.frame;
1259 	icount->brk = cnow.brk;
1260 	icount->overrun = cnow.overrun;
1261 	icount->buf_overrun = cnow.buf_overrun;
1262 	icount->parity = cnow.parity;
1263 	icount->rx = cnow.rx;
1264 	icount->tx = cnow.tx;
1265 	icount->cts = cnow.cts;
1266 	icount->dsr = cnow.dsr;
1267 	icount->rng = cnow.rng;
1268 	icount->dcd = cnow.dcd;
1269 	return 0;
1270 }
1271 
1272 /*
1273  * This routine is called by the upper-layer tty layer to signal that
1274  * incoming characters should be throttled.
1275  */
1276 static void mxser_throttle(struct tty_struct *tty)
1277 {
1278 	struct mxser_port *info = tty->driver_data;
1279 
1280 	if (I_IXOFF(tty)) {
1281 		if (info->board->must_hwid) {
1282 			info->IER &= ~MOXA_MUST_RECV_ISR;
1283 			outb(info->IER, info->ioaddr + UART_IER);
1284 		} else {
1285 			info->x_char = STOP_CHAR(tty);
1286 			outb(0, info->ioaddr + UART_IER);
1287 			info->IER |= UART_IER_THRI;
1288 			outb(info->IER, info->ioaddr + UART_IER);
1289 		}
1290 	}
1291 
1292 	if (C_CRTSCTS(tty)) {
1293 		info->MCR &= ~UART_MCR_RTS;
1294 		outb(info->MCR, info->ioaddr + UART_MCR);
1295 	}
1296 }
1297 
1298 static void mxser_unthrottle(struct tty_struct *tty)
1299 {
1300 	struct mxser_port *info = tty->driver_data;
1301 
1302 	/* startrx */
1303 	if (I_IXOFF(tty)) {
1304 		if (info->x_char)
1305 			info->x_char = 0;
1306 		else {
1307 			if (info->board->must_hwid) {
1308 				info->IER |= MOXA_MUST_RECV_ISR;
1309 				outb(info->IER, info->ioaddr + UART_IER);
1310 			} else {
1311 				info->x_char = START_CHAR(tty);
1312 				outb(0, info->ioaddr + UART_IER);
1313 				info->IER |= UART_IER_THRI;
1314 				outb(info->IER, info->ioaddr + UART_IER);
1315 			}
1316 		}
1317 	}
1318 
1319 	if (C_CRTSCTS(tty)) {
1320 		info->MCR |= UART_MCR_RTS;
1321 		outb(info->MCR, info->ioaddr + UART_MCR);
1322 	}
1323 }
1324 
1325 /*
1326  * mxser_stop() and mxser_start()
1327  *
1328  * This routines are called before setting or resetting tty->flow.stopped.
1329  * They enable or disable transmitter interrupts, as necessary.
1330  */
1331 static void mxser_stop(struct tty_struct *tty)
1332 {
1333 	struct mxser_port *info = tty->driver_data;
1334 	unsigned long flags;
1335 
1336 	spin_lock_irqsave(&info->slock, flags);
1337 	if (info->IER & UART_IER_THRI)
1338 		__mxser_stop_tx(info);
1339 	spin_unlock_irqrestore(&info->slock, flags);
1340 }
1341 
1342 static void mxser_start(struct tty_struct *tty)
1343 {
1344 	struct mxser_port *info = tty->driver_data;
1345 	unsigned long flags;
1346 
1347 	spin_lock_irqsave(&info->slock, flags);
1348 	if (!kfifo_is_empty(&info->port.xmit_fifo))
1349 		__mxser_start_tx(info);
1350 	spin_unlock_irqrestore(&info->slock, flags);
1351 }
1352 
1353 static void mxser_set_termios(struct tty_struct *tty,
1354 			      const struct ktermios *old_termios)
1355 {
1356 	struct mxser_port *info = tty->driver_data;
1357 	unsigned long flags;
1358 
1359 	spin_lock_irqsave(&info->slock, flags);
1360 	mxser_change_speed(tty, old_termios);
1361 	spin_unlock_irqrestore(&info->slock, flags);
1362 
1363 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
1364 		tty->hw_stopped = false;
1365 		mxser_start(tty);
1366 	}
1367 
1368 	/* Handle sw stopped */
1369 	if ((old_termios->c_iflag & IXON) && !I_IXON(tty)) {
1370 		tty->flow.stopped = 0;
1371 
1372 		if (info->board->must_hwid) {
1373 			spin_lock_irqsave(&info->slock, flags);
1374 			mxser_must_set_rx_sw_flow_control(info->ioaddr, false);
1375 			spin_unlock_irqrestore(&info->slock, flags);
1376 		}
1377 
1378 		mxser_start(tty);
1379 	}
1380 }
1381 
1382 static bool mxser_tx_empty(struct mxser_port *info)
1383 {
1384 	unsigned long flags;
1385 	u8 lsr;
1386 
1387 	spin_lock_irqsave(&info->slock, flags);
1388 	lsr = inb(info->ioaddr + UART_LSR);
1389 	spin_unlock_irqrestore(&info->slock, flags);
1390 
1391 	return !(lsr & UART_LSR_TEMT);
1392 }
1393 
1394 /*
1395  * mxser_wait_until_sent() --- wait until the transmitter is empty
1396  */
1397 static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
1398 {
1399 	struct mxser_port *info = tty->driver_data;
1400 	unsigned long expire, char_time;
1401 
1402 	if (info->type == PORT_UNKNOWN)
1403 		return;
1404 
1405 	if (info->xmit_fifo_size == 0)
1406 		return;		/* Just in case.... */
1407 
1408 	/*
1409 	 * Set the check interval to be 1/5 of the estimated time to
1410 	 * send a single character, and make it at least 1.  The check
1411 	 * interval should also be less than the timeout.
1412 	 *
1413 	 * Note: we have to use pretty tight timings here to satisfy
1414 	 * the NIST-PCTS.
1415 	 */
1416 	char_time = (info->timeout - HZ / 50) / info->xmit_fifo_size;
1417 	char_time = char_time / 5;
1418 	if (char_time == 0)
1419 		char_time = 1;
1420 	if (timeout && timeout < char_time)
1421 		char_time = timeout;
1422 
1423 	char_time = jiffies_to_msecs(char_time);
1424 
1425 	/*
1426 	 * If the transmitter hasn't cleared in twice the approximate
1427 	 * amount of time to send the entire FIFO, it probably won't
1428 	 * ever clear.  This assumes the UART isn't doing flow
1429 	 * control, which is currently the case.  Hence, if it ever
1430 	 * takes longer than info->timeout, this is probably due to a
1431 	 * UART bug of some kind.  So, we clamp the timeout parameter at
1432 	 * 2*info->timeout.
1433 	 */
1434 	if (!timeout || timeout > 2 * info->timeout)
1435 		timeout = 2 * info->timeout;
1436 
1437 	expire = jiffies + timeout;
1438 
1439 	while (mxser_tx_empty(info)) {
1440 		msleep_interruptible(char_time);
1441 		if (signal_pending(current))
1442 			break;
1443 		if (time_after(jiffies, expire))
1444 			break;
1445 	}
1446 }
1447 
1448 /*
1449  * This routine is called by tty_hangup() when a hangup is signaled.
1450  */
1451 static void mxser_hangup(struct tty_struct *tty)
1452 {
1453 	struct mxser_port *info = tty->driver_data;
1454 
1455 	mxser_flush_buffer(tty);
1456 	tty_port_hangup(&info->port);
1457 }
1458 
1459 /*
1460  * mxser_rs_break() --- routine which turns the break handling on or off
1461  */
1462 static int mxser_rs_break(struct tty_struct *tty, int break_state)
1463 {
1464 	struct mxser_port *info = tty->driver_data;
1465 	unsigned long flags;
1466 	u8 lcr;
1467 
1468 	spin_lock_irqsave(&info->slock, flags);
1469 	lcr = inb(info->ioaddr + UART_LCR);
1470 	if (break_state == -1)
1471 		lcr |= UART_LCR_SBC;
1472 	else
1473 		lcr &= ~UART_LCR_SBC;
1474 	outb(lcr, info->ioaddr + UART_LCR);
1475 	spin_unlock_irqrestore(&info->slock, flags);
1476 
1477 	return 0;
1478 }
1479 
1480 static bool mxser_receive_chars_new(struct mxser_port *port, u8 status)
1481 {
1482 	enum mxser_must_hwid hwid = port->board->must_hwid;
1483 	u8 gdl;
1484 
1485 	if (hwid == MOXA_OTHER_UART)
1486 		return false;
1487 	if (status & (UART_LSR_BRK_ERROR_BITS | MOXA_MUST_LSR_RERR))
1488 		return false;
1489 
1490 	gdl = inb(port->ioaddr + MOXA_MUST_GDL_REGISTER);
1491 	if (hwid == MOXA_MUST_MU150_HWID)
1492 		gdl &= MOXA_MUST_GDL_MASK;
1493 
1494 	while (gdl--) {
1495 		u8 ch = inb(port->ioaddr + UART_RX);
1496 		if (!tty_insert_flip_char(&port->port, ch, 0))
1497 			port->icount.buf_overrun++;
1498 	}
1499 
1500 	return true;
1501 }
1502 
1503 static u8 mxser_receive_chars_old(struct tty_struct *tty,
1504 		                struct mxser_port *port, u8 status)
1505 {
1506 	enum mxser_must_hwid hwid = port->board->must_hwid;
1507 	int ignored = 0;
1508 	int max = 256;
1509 	u8 ch;
1510 
1511 	do {
1512 		if (max-- < 0)
1513 			break;
1514 
1515 		ch = inb(port->ioaddr + UART_RX);
1516 		if (hwid && (status & UART_LSR_OE))
1517 			outb(port->FCR | UART_FCR_CLEAR_RCVR,
1518 					port->ioaddr + UART_FCR);
1519 		status &= port->read_status_mask;
1520 		if (status & port->ignore_status_mask) {
1521 			if (++ignored > 100)
1522 				break;
1523 		} else {
1524 			char flag = 0;
1525 			if (status & UART_LSR_BRK_ERROR_BITS) {
1526 				if (status & UART_LSR_BI) {
1527 					flag = TTY_BREAK;
1528 					port->icount.brk++;
1529 
1530 					if (port->port.flags & ASYNC_SAK)
1531 						do_SAK(tty);
1532 				} else if (status & UART_LSR_PE) {
1533 					flag = TTY_PARITY;
1534 					port->icount.parity++;
1535 				} else if (status & UART_LSR_FE) {
1536 					flag = TTY_FRAME;
1537 					port->icount.frame++;
1538 				} else if (status & UART_LSR_OE) {
1539 					flag = TTY_OVERRUN;
1540 					port->icount.overrun++;
1541 				}
1542 			}
1543 			if (!tty_insert_flip_char(&port->port, ch, flag)) {
1544 				port->icount.buf_overrun++;
1545 				break;
1546 			}
1547 		}
1548 
1549 		if (hwid)
1550 			break;
1551 
1552 		status = inb(port->ioaddr + UART_LSR);
1553 	} while (status & UART_LSR_DR);
1554 
1555 	return status;
1556 }
1557 
1558 static u8 mxser_receive_chars(struct tty_struct *tty,
1559 		struct mxser_port *port, u8 status)
1560 {
1561 	if (!mxser_receive_chars_new(port, status))
1562 		status = mxser_receive_chars_old(tty, port, status);
1563 
1564 	tty_flip_buffer_push(&port->port);
1565 
1566 	return status;
1567 }
1568 
1569 static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port)
1570 {
1571 	int count;
1572 
1573 	if (port->x_char) {
1574 		outb(port->x_char, port->ioaddr + UART_TX);
1575 		port->x_char = 0;
1576 		port->icount.tx++;
1577 		return;
1578 	}
1579 
1580 	if (kfifo_is_empty(&port->port.xmit_fifo) || tty->flow.stopped ||
1581 			(tty->hw_stopped && !mxser_16550A_or_MUST(port))) {
1582 		__mxser_stop_tx(port);
1583 		return;
1584 	}
1585 
1586 	count = port->xmit_fifo_size;
1587 	do {
1588 		unsigned char c;
1589 
1590 		if (!kfifo_get(&port->port.xmit_fifo, &c))
1591 			break;
1592 
1593 		outb(c, port->ioaddr + UART_TX);
1594 		port->icount.tx++;
1595 	} while (--count > 0);
1596 
1597 	if (kfifo_len(&port->port.xmit_fifo) < WAKEUP_CHARS)
1598 		tty_wakeup(tty);
1599 
1600 	if (kfifo_is_empty(&port->port.xmit_fifo))
1601 		__mxser_stop_tx(port);
1602 }
1603 
1604 static bool mxser_port_isr(struct mxser_port *port)
1605 {
1606 	struct tty_struct *tty;
1607 	u8 iir, status;
1608 	bool error = false;
1609 
1610 	iir = inb(port->ioaddr + UART_IIR);
1611 	if (iir & UART_IIR_NO_INT)
1612 		return true;
1613 
1614 	iir &= MOXA_MUST_IIR_MASK;
1615 	tty = tty_port_tty_get(&port->port);
1616 	if (!tty) {
1617 		status = inb(port->ioaddr + UART_LSR);
1618 		outb(port->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
1619 				port->ioaddr + UART_FCR);
1620 		inb(port->ioaddr + UART_MSR);
1621 
1622 		error = true;
1623 		goto put_tty;
1624 	}
1625 
1626 	status = inb(port->ioaddr + UART_LSR);
1627 
1628 	if (port->board->must_hwid) {
1629 		if (iir == MOXA_MUST_IIR_GDA ||
1630 		    iir == MOXA_MUST_IIR_RDA ||
1631 		    iir == MOXA_MUST_IIR_RTO ||
1632 		    iir == MOXA_MUST_IIR_LSR)
1633 			status = mxser_receive_chars(tty, port, status);
1634 	} else {
1635 		status &= port->read_status_mask;
1636 		if (status & UART_LSR_DR)
1637 			status = mxser_receive_chars(tty, port, status);
1638 	}
1639 
1640 	mxser_check_modem_status(tty, port);
1641 
1642 	if (port->board->must_hwid) {
1643 		if (iir == 0x02 && (status & UART_LSR_THRE))
1644 			mxser_transmit_chars(tty, port);
1645 	} else {
1646 		if (status & UART_LSR_THRE)
1647 			mxser_transmit_chars(tty, port);
1648 	}
1649 
1650 put_tty:
1651 	tty_kref_put(tty);
1652 
1653 	return error;
1654 }
1655 
1656 /*
1657  * This is the serial driver's generic interrupt routine
1658  */
1659 static irqreturn_t mxser_interrupt(int irq, void *dev_id)
1660 {
1661 	struct mxser_board *brd = dev_id;
1662 	struct mxser_port *port;
1663 	unsigned int int_cnt, pass_counter = 0;
1664 	unsigned int i, max = brd->nports;
1665 	int handled = IRQ_NONE;
1666 	u8 irqbits, bits, mask = BIT(max) - 1;
1667 
1668 	while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
1669 		irqbits = inb(brd->vector) & mask;
1670 		if (irqbits == mask)
1671 			break;
1672 
1673 		handled = IRQ_HANDLED;
1674 		for (i = 0, bits = 1; i < max; i++, irqbits |= bits, bits <<= 1) {
1675 			if (irqbits == mask)
1676 				break;
1677 			if (bits & irqbits)
1678 				continue;
1679 			port = &brd->ports[i];
1680 
1681 			int_cnt = 0;
1682 			spin_lock(&port->slock);
1683 			do {
1684 				if (mxser_port_isr(port))
1685 					break;
1686 			} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
1687 			spin_unlock(&port->slock);
1688 		}
1689 	}
1690 
1691 	return handled;
1692 }
1693 
1694 static const struct tty_operations mxser_ops = {
1695 	.open = mxser_open,
1696 	.close = mxser_close,
1697 	.write = mxser_write,
1698 	.put_char = mxser_put_char,
1699 	.flush_chars = mxser_flush_chars,
1700 	.write_room = mxser_write_room,
1701 	.chars_in_buffer = mxser_chars_in_buffer,
1702 	.flush_buffer = mxser_flush_buffer,
1703 	.ioctl = mxser_ioctl,
1704 	.throttle = mxser_throttle,
1705 	.unthrottle = mxser_unthrottle,
1706 	.set_termios = mxser_set_termios,
1707 	.stop = mxser_stop,
1708 	.start = mxser_start,
1709 	.hangup = mxser_hangup,
1710 	.break_ctl = mxser_rs_break,
1711 	.wait_until_sent = mxser_wait_until_sent,
1712 	.tiocmget = mxser_tiocmget,
1713 	.tiocmset = mxser_tiocmset,
1714 	.set_serial = mxser_set_serial_info,
1715 	.get_serial = mxser_get_serial_info,
1716 	.get_icount = mxser_get_icount,
1717 };
1718 
1719 static const struct tty_port_operations mxser_port_ops = {
1720 	.carrier_raised = mxser_carrier_raised,
1721 	.dtr_rts = mxser_dtr_rts,
1722 	.activate = mxser_activate,
1723 	.shutdown = mxser_shutdown_port,
1724 };
1725 
1726 /*
1727  * The MOXA Smartio/Industio serial driver boot-time initialization code!
1728  */
1729 
1730 static void mxser_initbrd(struct mxser_board *brd, bool high_baud)
1731 {
1732 	struct mxser_port *info;
1733 	unsigned int i;
1734 	bool is_mu860;
1735 
1736 	brd->must_hwid = mxser_must_get_hwid(brd->ports[0].ioaddr);
1737 	is_mu860 = brd->must_hwid == MOXA_MUST_MU860_HWID;
1738 
1739 	for (i = 0; i < UART_INFO_NUM; i++) {
1740 		if (Gpci_uart_info[i].type == brd->must_hwid) {
1741 			brd->max_baud = Gpci_uart_info[i].max_baud;
1742 
1743 			/* exception....CP-102 */
1744 			if (high_baud)
1745 				brd->max_baud = 921600;
1746 			break;
1747 		}
1748 	}
1749 
1750 	if (is_mu860) {
1751 		/* set to RS232 mode by default */
1752 		outb(0, brd->vector + 4);
1753 		outb(0, brd->vector + 0x0c);
1754 	}
1755 
1756 	for (i = 0; i < brd->nports; i++) {
1757 		info = &brd->ports[i];
1758 		if (is_mu860) {
1759 			if (i < 4)
1760 				info->opmode_ioaddr = brd->vector + 4;
1761 			else
1762 				info->opmode_ioaddr = brd->vector + 0x0c;
1763 		}
1764 		tty_port_init(&info->port);
1765 		info->port.ops = &mxser_port_ops;
1766 		info->board = brd;
1767 
1768 		/* Enhance mode enabled here */
1769 		if (brd->must_hwid != MOXA_OTHER_UART)
1770 			mxser_must_set_enhance_mode(info->ioaddr, true);
1771 
1772 		info->type = PORT_16550A;
1773 
1774 		mxser_process_txrx_fifo(info);
1775 
1776 		info->port.close_delay = 5 * HZ / 10;
1777 		info->port.closing_wait = 30 * HZ;
1778 		spin_lock_init(&info->slock);
1779 
1780 		/* before set INT ISR, disable all int */
1781 		outb(inb(info->ioaddr + UART_IER) & 0xf0,
1782 			info->ioaddr + UART_IER);
1783 	}
1784 }
1785 
1786 static int mxser_probe(struct pci_dev *pdev,
1787 		const struct pci_device_id *ent)
1788 {
1789 	struct mxser_board *brd;
1790 	unsigned int i, base;
1791 	unsigned long ioaddress;
1792 	unsigned short nports = MXSER_NPORTS(ent->driver_data);
1793 	struct device *tty_dev;
1794 	int retval = -EINVAL;
1795 
1796 	i = find_first_zero_bit(mxser_boards, MXSER_BOARDS);
1797 	if (i >= MXSER_BOARDS) {
1798 		dev_err(&pdev->dev, "too many boards found (maximum %d), board "
1799 				"not configured\n", MXSER_BOARDS);
1800 		goto err;
1801 	}
1802 
1803 	brd = devm_kzalloc(&pdev->dev, struct_size(brd, ports, nports),
1804 			GFP_KERNEL);
1805 	if (!brd)
1806 		goto err;
1807 
1808 	brd->idx = i;
1809 	__set_bit(brd->idx, mxser_boards);
1810 	base = i * MXSER_PORTS_PER_BOARD;
1811 
1812 	retval = pcim_enable_device(pdev);
1813 	if (retval) {
1814 		dev_err(&pdev->dev, "PCI enable failed\n");
1815 		goto err_zero;
1816 	}
1817 
1818 	/* io address */
1819 	ioaddress = pci_resource_start(pdev, 2);
1820 	retval = pci_request_region(pdev, 2, "mxser(IO)");
1821 	if (retval)
1822 		goto err_zero;
1823 
1824 	brd->nports = nports;
1825 	for (i = 0; i < nports; i++)
1826 		brd->ports[i].ioaddr = ioaddress + 8 * i;
1827 
1828 	/* vector */
1829 	ioaddress = pci_resource_start(pdev, 3);
1830 	retval = pci_request_region(pdev, 3, "mxser(vector)");
1831 	if (retval)
1832 		goto err_zero;
1833 	brd->vector = ioaddress;
1834 
1835 	/* irq */
1836 	brd->irq = pdev->irq;
1837 
1838 	mxser_initbrd(brd, ent->driver_data & MXSER_HIGHBAUD);
1839 
1840 	retval = devm_request_irq(&pdev->dev, brd->irq, mxser_interrupt,
1841 			IRQF_SHARED, "mxser", brd);
1842 	if (retval) {
1843 		dev_err(&pdev->dev, "request irq failed");
1844 		goto err_relbrd;
1845 	}
1846 
1847 	for (i = 0; i < nports; i++) {
1848 		tty_dev = tty_port_register_device(&brd->ports[i].port,
1849 				mxvar_sdriver, base + i, &pdev->dev);
1850 		if (IS_ERR(tty_dev)) {
1851 			retval = PTR_ERR(tty_dev);
1852 			for (; i > 0; i--)
1853 				tty_unregister_device(mxvar_sdriver,
1854 					base + i - 1);
1855 			goto err_relbrd;
1856 		}
1857 	}
1858 
1859 	pci_set_drvdata(pdev, brd);
1860 
1861 	return 0;
1862 err_relbrd:
1863 	for (i = 0; i < nports; i++)
1864 		tty_port_destroy(&brd->ports[i].port);
1865 err_zero:
1866 	__clear_bit(brd->idx, mxser_boards);
1867 err:
1868 	return retval;
1869 }
1870 
1871 static void mxser_remove(struct pci_dev *pdev)
1872 {
1873 	struct mxser_board *brd = pci_get_drvdata(pdev);
1874 	unsigned int i, base = brd->idx * MXSER_PORTS_PER_BOARD;
1875 
1876 	for (i = 0; i < brd->nports; i++) {
1877 		tty_unregister_device(mxvar_sdriver, base + i);
1878 		tty_port_destroy(&brd->ports[i].port);
1879 	}
1880 
1881 	__clear_bit(brd->idx, mxser_boards);
1882 }
1883 
1884 static struct pci_driver mxser_driver = {
1885 	.name = "mxser",
1886 	.id_table = mxser_pcibrds,
1887 	.probe = mxser_probe,
1888 	.remove = mxser_remove
1889 };
1890 
1891 static int __init mxser_module_init(void)
1892 {
1893 	int retval;
1894 
1895 	mxvar_sdriver = tty_alloc_driver(MXSER_PORTS, TTY_DRIVER_REAL_RAW |
1896 			TTY_DRIVER_DYNAMIC_DEV);
1897 	if (IS_ERR(mxvar_sdriver))
1898 		return PTR_ERR(mxvar_sdriver);
1899 
1900 	/* Initialize the tty_driver structure */
1901 	mxvar_sdriver->name = "ttyMI";
1902 	mxvar_sdriver->major = ttymajor;
1903 	mxvar_sdriver->minor_start = 0;
1904 	mxvar_sdriver->type = TTY_DRIVER_TYPE_SERIAL;
1905 	mxvar_sdriver->subtype = SERIAL_TYPE_NORMAL;
1906 	mxvar_sdriver->init_termios = tty_std_termios;
1907 	mxvar_sdriver->init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
1908 	tty_set_operations(mxvar_sdriver, &mxser_ops);
1909 
1910 	retval = tty_register_driver(mxvar_sdriver);
1911 	if (retval) {
1912 		printk(KERN_ERR "Couldn't install MOXA Smartio/Industio family "
1913 				"tty driver !\n");
1914 		goto err_put;
1915 	}
1916 
1917 	retval = pci_register_driver(&mxser_driver);
1918 	if (retval) {
1919 		printk(KERN_ERR "mxser: can't register pci driver\n");
1920 		goto err_unr;
1921 	}
1922 
1923 	return 0;
1924 err_unr:
1925 	tty_unregister_driver(mxvar_sdriver);
1926 err_put:
1927 	tty_driver_kref_put(mxvar_sdriver);
1928 	return retval;
1929 }
1930 
1931 static void __exit mxser_module_exit(void)
1932 {
1933 	pci_unregister_driver(&mxser_driver);
1934 	tty_unregister_driver(mxvar_sdriver);
1935 	tty_driver_kref_put(mxvar_sdriver);
1936 }
1937 
1938 module_init(mxser_module_init);
1939 module_exit(mxser_module_exit);
1940