xref: /linux/drivers/tty/mxser.c (revision 55d0969c451159cff86949b38c39171cab962069)
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 static const struct pci_device_id mxser_pcibrds[] = {
212 	{ PCI_DEVICE_DATA(MOXA, C168,		8) },
213 	{ PCI_DEVICE_DATA(MOXA, C104,		4) },
214 	{ PCI_DEVICE_DATA(MOXA, CP132,		2) },
215 	{ PCI_DEVICE_DATA(MOXA, CP114,		4) },
216 	{ PCI_DEVICE_DATA(MOXA, CT114,		4) },
217 	{ PCI_DEVICE_DATA(MOXA, CP102,		2 | MXSER_HIGHBAUD) },
218 	{ PCI_DEVICE_DATA(MOXA, CP104U,		4) },
219 	{ PCI_DEVICE_DATA(MOXA, CP168U,		8) },
220 	{ PCI_DEVICE_DATA(MOXA, CP132U,		2) },
221 	{ PCI_DEVICE_DATA(MOXA, CP134U,		4) },
222 	{ PCI_DEVICE_DATA(MOXA, CP104JU,	4) },
223 	{ PCI_DEVICE_DATA(MOXA, RC7000,		8) }, /* RC7000 */
224 	{ PCI_DEVICE_DATA(MOXA, CP118U,		8) },
225 	{ PCI_DEVICE_DATA(MOXA, CP102UL,	2) },
226 	{ PCI_DEVICE_DATA(MOXA, CP102U,		2) },
227 	{ PCI_DEVICE_DATA(MOXA, CP118EL,	8) },
228 	{ PCI_DEVICE_DATA(MOXA, CP168EL,	8) },
229 	{ PCI_DEVICE_DATA(MOXA, CP104EL,	4) },
230 	{ PCI_DEVICE_DATA(MOXA, CB108,		8) },
231 	{ PCI_DEVICE_DATA(MOXA, CB114,		4) },
232 	{ PCI_DEVICE_DATA(MOXA, CB134I,		4) },
233 	{ PCI_DEVICE_DATA(MOXA, CP138U,		8) },
234 	{ PCI_DEVICE_DATA(MOXA, POS104UL,	4) },
235 	{ PCI_DEVICE_DATA(MOXA, CP114UL,	4) },
236 	{ PCI_DEVICE_DATA(MOXA, CP102UF,	2) },
237 	{ PCI_DEVICE_DATA(MOXA, CP112UL,	2) },
238 	{ }
239 };
240 MODULE_DEVICE_TABLE(pci, mxser_pcibrds);
241 
242 static int ttymajor = MXSERMAJOR;
243 
244 /* Variables for insmod */
245 
246 MODULE_AUTHOR("Casper Yang");
247 MODULE_DESCRIPTION("MOXA Smartio/Industio Family Multiport Board Device Driver");
248 module_param(ttymajor, int, 0);
249 MODULE_LICENSE("GPL");
250 
251 struct mxser_board;
252 
253 struct mxser_port {
254 	struct tty_port port;
255 	struct mxser_board *board;
256 
257 	unsigned long ioaddr;
258 	unsigned long opmode_ioaddr;
259 
260 	u8 rx_high_water;
261 	u8 rx_low_water;
262 	int type;		/* UART type */
263 
264 	u8 x_char;		/* xon/xoff character */
265 	u8 IER;			/* Interrupt Enable Register */
266 	u8 MCR;			/* Modem control register */
267 	u8 FCR;			/* FIFO control register */
268 
269 	struct async_icount icount; /* kernel counters for 4 input interrupts */
270 	unsigned int timeout;
271 
272 	u8 read_status_mask;
273 	u8 ignore_status_mask;
274 	u8 xmit_fifo_size;
275 
276 	spinlock_t slock;
277 };
278 
279 struct mxser_board {
280 	unsigned int idx;
281 	unsigned short nports;
282 	int irq;
283 	unsigned long vector;
284 
285 	enum mxser_must_hwid must_hwid;
286 	speed_t max_baud;
287 
288 	struct mxser_port ports[] /* __counted_by(nports) */;
289 };
290 
291 static DECLARE_BITMAP(mxser_boards, MXSER_BOARDS);
292 static struct tty_driver *mxvar_sdriver;
293 
294 static u8 __mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set,
295 		bool restore_LCR)
296 {
297 	u8 oldlcr, efr;
298 
299 	oldlcr = inb(baseio + UART_LCR);
300 	outb(MOXA_MUST_ENTER_ENHANCED, baseio + UART_LCR);
301 
302 	efr = inb(baseio + MOXA_MUST_EFR_REGISTER);
303 	efr &= ~clear;
304 	efr |= set;
305 
306 	outb(efr, baseio + MOXA_MUST_EFR_REGISTER);
307 
308 	if (restore_LCR)
309 		outb(oldlcr, baseio + UART_LCR);
310 
311 	return oldlcr;
312 }
313 
314 static u8 mxser_must_select_bank(unsigned long baseio, u8 bank)
315 {
316 	return __mxser_must_set_EFR(baseio, MOXA_MUST_EFR_BANK_MASK, bank,
317 			false);
318 }
319 
320 static void mxser_set_must_xon1_value(unsigned long baseio, u8 value)
321 {
322 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
323 	outb(value, baseio + MOXA_MUST_XON1_REGISTER);
324 	outb(oldlcr, baseio + UART_LCR);
325 }
326 
327 static void mxser_set_must_xoff1_value(unsigned long baseio, u8 value)
328 {
329 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
330 	outb(value, baseio + MOXA_MUST_XOFF1_REGISTER);
331 	outb(oldlcr, baseio + UART_LCR);
332 }
333 
334 static void mxser_set_must_fifo_value(struct mxser_port *info)
335 {
336 	u8 oldlcr = mxser_must_select_bank(info->ioaddr, MOXA_MUST_EFR_BANK1);
337 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTH_REGISTER);
338 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTI_REGISTER);
339 	outb(info->rx_low_water, info->ioaddr + MOXA_MUST_RBRTL_REGISTER);
340 	outb(oldlcr, info->ioaddr + UART_LCR);
341 }
342 
343 static void mxser_set_must_enum_value(unsigned long baseio, u8 value)
344 {
345 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
346 	outb(value, baseio + MOXA_MUST_ENUM_REGISTER);
347 	outb(oldlcr, baseio + UART_LCR);
348 }
349 
350 static u8 mxser_get_must_hardware_id(unsigned long baseio)
351 {
352 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
353 	u8 id = inb(baseio + MOXA_MUST_HWID_REGISTER);
354 	outb(oldlcr, baseio + UART_LCR);
355 
356 	return id;
357 }
358 
359 static void mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set)
360 {
361 	__mxser_must_set_EFR(baseio, clear, set, true);
362 }
363 
364 static void mxser_must_set_enhance_mode(unsigned long baseio, bool enable)
365 {
366 	mxser_must_set_EFR(baseio,
367 			enable ? 0 : MOXA_MUST_EFR_EFRB_ENABLE,
368 			enable ? MOXA_MUST_EFR_EFRB_ENABLE : 0);
369 }
370 
371 static void mxser_must_no_sw_flow_control(unsigned long baseio)
372 {
373 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_MASK, 0);
374 }
375 
376 static void mxser_must_set_tx_sw_flow_control(unsigned long baseio, bool enable)
377 {
378 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_TX_MASK,
379 			enable ? MOXA_MUST_EFR_SF_TX1 : 0);
380 }
381 
382 static void mxser_must_set_rx_sw_flow_control(unsigned long baseio, bool enable)
383 {
384 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_RX_MASK,
385 			enable ? MOXA_MUST_EFR_SF_RX1 : 0);
386 }
387 
388 static enum mxser_must_hwid mxser_must_get_hwid(unsigned long io)
389 {
390 	u8 oldmcr, hwid;
391 	int i;
392 
393 	outb(0, io + UART_LCR);
394 	mxser_must_set_enhance_mode(io, false);
395 	oldmcr = inb(io + UART_MCR);
396 	outb(0, io + UART_MCR);
397 	mxser_set_must_xon1_value(io, 0x11);
398 	if (inb(io + UART_MCR) != 0) {
399 		outb(oldmcr, io + UART_MCR);
400 		return MOXA_OTHER_UART;
401 	}
402 
403 	hwid = mxser_get_must_hardware_id(io);
404 	for (i = 1; i < UART_INFO_NUM; i++) /* 0 = OTHER_UART */
405 		if (hwid == Gpci_uart_info[i].type)
406 			return hwid;
407 
408 	return MOXA_OTHER_UART;
409 }
410 
411 static bool mxser_16550A_or_MUST(struct mxser_port *info)
412 {
413 	return info->type == PORT_16550A || info->board->must_hwid;
414 }
415 
416 static void mxser_process_txrx_fifo(struct mxser_port *info)
417 {
418 	unsigned int i;
419 
420 	if (info->type == PORT_16450 || info->type == PORT_8250) {
421 		info->rx_high_water = 1;
422 		info->rx_low_water = 1;
423 		info->xmit_fifo_size = 1;
424 		return;
425 	}
426 
427 	for (i = 0; i < UART_INFO_NUM; i++)
428 		if (info->board->must_hwid == Gpci_uart_info[i].type) {
429 			info->rx_low_water = Gpci_uart_info[i].rx_low_water;
430 			info->rx_high_water = Gpci_uart_info[i].rx_high_water;
431 			info->xmit_fifo_size = Gpci_uart_info[i].fifo_size;
432 			break;
433 		}
434 }
435 
436 static void __mxser_start_tx(struct mxser_port *info)
437 {
438 	outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);
439 	info->IER |= UART_IER_THRI;
440 	outb(info->IER, info->ioaddr + UART_IER);
441 }
442 
443 static void mxser_start_tx(struct mxser_port *info)
444 {
445 	unsigned long flags;
446 
447 	spin_lock_irqsave(&info->slock, flags);
448 	__mxser_start_tx(info);
449 	spin_unlock_irqrestore(&info->slock, flags);
450 }
451 
452 static void __mxser_stop_tx(struct mxser_port *info)
453 {
454 	info->IER &= ~UART_IER_THRI;
455 	outb(info->IER, info->ioaddr + UART_IER);
456 }
457 
458 static bool mxser_carrier_raised(struct tty_port *port)
459 {
460 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
461 
462 	return inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD;
463 }
464 
465 static void mxser_dtr_rts(struct tty_port *port, bool active)
466 {
467 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
468 	unsigned long flags;
469 	u8 mcr;
470 
471 	spin_lock_irqsave(&mp->slock, flags);
472 	mcr = inb(mp->ioaddr + UART_MCR);
473 	if (active)
474 		mcr |= UART_MCR_DTR | UART_MCR_RTS;
475 	else
476 		mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
477 	outb(mcr, mp->ioaddr + UART_MCR);
478 	spin_unlock_irqrestore(&mp->slock, flags);
479 }
480 
481 static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
482 {
483 	struct mxser_port *info = tty->driver_data;
484 	unsigned int quot = 0, baud;
485 	unsigned char cval;
486 	u64 timeout;
487 
488 	if (newspd > info->board->max_baud)
489 		return -1;
490 
491 	if (newspd == 134) {
492 		quot = 2 * MXSER_BAUD_BASE / 269;
493 		tty_encode_baud_rate(tty, 134, 134);
494 	} else if (newspd) {
495 		quot = MXSER_BAUD_BASE / newspd;
496 		if (quot == 0)
497 			quot = 1;
498 		baud = MXSER_BAUD_BASE / quot;
499 		tty_encode_baud_rate(tty, baud, baud);
500 	} else {
501 		quot = 0;
502 	}
503 
504 	/*
505 	 * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the
506 	 * u64 domain
507 	 */
508 	timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot;
509 	do_div(timeout, MXSER_BAUD_BASE);
510 	info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */
511 
512 	if (quot) {
513 		info->MCR |= UART_MCR_DTR;
514 		outb(info->MCR, info->ioaddr + UART_MCR);
515 	} else {
516 		info->MCR &= ~UART_MCR_DTR;
517 		outb(info->MCR, info->ioaddr + UART_MCR);
518 		return 0;
519 	}
520 
521 	cval = inb(info->ioaddr + UART_LCR);
522 
523 	outb(cval | UART_LCR_DLAB, info->ioaddr + UART_LCR);	/* set DLAB */
524 
525 	outb(quot & 0xff, info->ioaddr + UART_DLL);	/* LS of divisor */
526 	outb(quot >> 8, info->ioaddr + UART_DLM);	/* MS of divisor */
527 	outb(cval, info->ioaddr + UART_LCR);	/* reset DLAB */
528 
529 	if (C_BAUD(tty) == BOTHER) {
530 		quot = MXSER_BAUD_BASE % newspd;
531 		quot *= 8;
532 		if (quot % newspd > newspd / 2) {
533 			quot /= newspd;
534 			quot++;
535 		} else
536 			quot /= newspd;
537 
538 		mxser_set_must_enum_value(info->ioaddr, quot);
539 	} else {
540 		mxser_set_must_enum_value(info->ioaddr, 0);
541 	}
542 
543 	return 0;
544 }
545 
546 static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
547 		u8 msr)
548 {
549 	bool cts = msr & UART_MSR_CTS;
550 
551 	if (tty->hw_stopped) {
552 		if (cts) {
553 			tty->hw_stopped = false;
554 
555 			if (!mxser_16550A_or_MUST(info))
556 				__mxser_start_tx(info);
557 			tty_wakeup(tty);
558 		}
559 		return;
560 	} else if (cts)
561 		return;
562 
563 	tty->hw_stopped = true;
564 	if (!mxser_16550A_or_MUST(info))
565 		__mxser_stop_tx(info);
566 }
567 
568 /*
569  * This routine is called to set the UART divisor registers to match
570  * the specified baud rate for a serial port.
571  */
572 static void mxser_change_speed(struct tty_struct *tty,
573 			       const struct ktermios *old_termios)
574 {
575 	struct mxser_port *info = tty->driver_data;
576 	unsigned cflag, cval;
577 
578 	cflag = tty->termios.c_cflag;
579 
580 	if (mxser_set_baud(tty, tty_get_baud_rate(tty))) {
581 		/* Use previous rate on a failure */
582 		if (old_termios) {
583 			speed_t baud = tty_termios_baud_rate(old_termios);
584 			tty_encode_baud_rate(tty, baud, baud);
585 		}
586 	}
587 
588 	/* byte size and parity */
589 	cval = UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
590 
591 	if (cflag & CSTOPB)
592 		cval |= UART_LCR_STOP;
593 	if (cflag & PARENB)
594 		cval |= UART_LCR_PARITY;
595 	if (!(cflag & PARODD))
596 		cval |= UART_LCR_EPAR;
597 	if (cflag & CMSPAR)
598 		cval |= UART_LCR_SPAR;
599 
600 	info->FCR = 0;
601 	if (info->board->must_hwid) {
602 		info->FCR |= UART_FCR_ENABLE_FIFO |
603 			MOXA_MUST_FCR_GDA_MODE_ENABLE;
604 		mxser_set_must_fifo_value(info);
605 	} else if (info->type != PORT_8250 && info->type != PORT_16450) {
606 		info->FCR |= UART_FCR_ENABLE_FIFO;
607 		switch (info->rx_high_water) {
608 		case 1:
609 			info->FCR |= UART_FCR_TRIGGER_1;
610 			break;
611 		case 4:
612 			info->FCR |= UART_FCR_TRIGGER_4;
613 			break;
614 		case 8:
615 			info->FCR |= UART_FCR_TRIGGER_8;
616 			break;
617 		default:
618 			info->FCR |= UART_FCR_TRIGGER_14;
619 			break;
620 		}
621 	}
622 
623 	/* CTS flow control flag and modem status interrupts */
624 	info->IER &= ~UART_IER_MSI;
625 	info->MCR &= ~UART_MCR_AFE;
626 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
627 	if (cflag & CRTSCTS) {
628 		info->IER |= UART_IER_MSI;
629 		if (mxser_16550A_or_MUST(info)) {
630 			info->MCR |= UART_MCR_AFE;
631 		} else {
632 			mxser_handle_cts(tty, info,
633 					inb(info->ioaddr + UART_MSR));
634 		}
635 	}
636 	outb(info->MCR, info->ioaddr + UART_MCR);
637 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
638 	if (~cflag & CLOCAL)
639 		info->IER |= UART_IER_MSI;
640 	outb(info->IER, info->ioaddr + UART_IER);
641 
642 	/*
643 	 * Set up parity check flag
644 	 */
645 	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
646 	if (I_INPCK(tty))
647 		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
648 	if (I_BRKINT(tty) || I_PARMRK(tty))
649 		info->read_status_mask |= UART_LSR_BI;
650 
651 	info->ignore_status_mask = 0;
652 
653 	if (I_IGNBRK(tty)) {
654 		info->ignore_status_mask |= UART_LSR_BI;
655 		info->read_status_mask |= UART_LSR_BI;
656 		/*
657 		 * If we're ignore parity and break indicators, ignore
658 		 * overruns too.  (For real raw support).
659 		 */
660 		if (I_IGNPAR(tty)) {
661 			info->ignore_status_mask |=
662 						UART_LSR_OE |
663 						UART_LSR_PE |
664 						UART_LSR_FE;
665 			info->read_status_mask |=
666 						UART_LSR_OE |
667 						UART_LSR_PE |
668 						UART_LSR_FE;
669 		}
670 	}
671 	if (info->board->must_hwid) {
672 		mxser_set_must_xon1_value(info->ioaddr, START_CHAR(tty));
673 		mxser_set_must_xoff1_value(info->ioaddr, STOP_CHAR(tty));
674 		mxser_must_set_rx_sw_flow_control(info->ioaddr, I_IXON(tty));
675 		mxser_must_set_tx_sw_flow_control(info->ioaddr, I_IXOFF(tty));
676 	}
677 
678 
679 	outb(info->FCR, info->ioaddr + UART_FCR);
680 	outb(cval, info->ioaddr + UART_LCR);
681 }
682 
683 static u8 mxser_check_modem_status(struct tty_struct *tty,
684 				struct mxser_port *port)
685 {
686 	u8 msr = inb(port->ioaddr + UART_MSR);
687 
688 	if (!(msr & UART_MSR_ANY_DELTA))
689 		return msr;
690 
691 	/* update input line counters */
692 	if (msr & UART_MSR_TERI)
693 		port->icount.rng++;
694 	if (msr & UART_MSR_DDSR)
695 		port->icount.dsr++;
696 	if (msr & UART_MSR_DDCD)
697 		port->icount.dcd++;
698 	if (msr & UART_MSR_DCTS)
699 		port->icount.cts++;
700 	wake_up_interruptible(&port->port.delta_msr_wait);
701 
702 	if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) {
703 		if (msr & UART_MSR_DCD)
704 			wake_up_interruptible(&port->port.open_wait);
705 	}
706 
707 	if (tty_port_cts_enabled(&port->port))
708 		mxser_handle_cts(tty, port, msr);
709 
710 	return msr;
711 }
712 
713 static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
714 {
715 	u8 fcr = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
716 
717 	if (info->board->must_hwid)
718 		fcr |= MOXA_MUST_FCR_GDA_MODE_ENABLE;
719 
720 	outb(fcr, info->ioaddr + UART_FCR);
721 }
722 
723 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
724 {
725 	struct mxser_port *info = container_of(port, struct mxser_port, port);
726 	unsigned long flags;
727 	int ret;
728 
729 	ret = tty_port_alloc_xmit_buf(port);
730 	if (ret < 0)
731 		return ret;
732 
733 	spin_lock_irqsave(&info->slock, flags);
734 
735 	if (!info->type) {
736 		set_bit(TTY_IO_ERROR, &tty->flags);
737 		spin_unlock_irqrestore(&info->slock, flags);
738 		ret = 0;
739 		goto err_free_xmit;
740 	}
741 
742 	/*
743 	 * Clear the FIFO buffers and disable them
744 	 * (they will be reenabled in mxser_change_speed())
745 	 */
746 	mxser_disable_and_clear_FIFO(info);
747 
748 	/*
749 	 * At this point there's no way the LSR could still be 0xFF;
750 	 * if it is, then bail out, because there's likely no UART
751 	 * here.
752 	 */
753 	if (inb(info->ioaddr + UART_LSR) == 0xff) {
754 		spin_unlock_irqrestore(&info->slock, flags);
755 		if (capable(CAP_SYS_ADMIN)) {
756 			set_bit(TTY_IO_ERROR, &tty->flags);
757 			return 0;
758 		}
759 
760 		ret = -ENODEV;
761 		goto err_free_xmit;
762 	}
763 
764 	/*
765 	 * Clear the interrupt registers.
766 	 */
767 	(void) inb(info->ioaddr + UART_LSR);
768 	(void) inb(info->ioaddr + UART_RX);
769 	(void) inb(info->ioaddr + UART_IIR);
770 	(void) inb(info->ioaddr + UART_MSR);
771 
772 	/*
773 	 * Now, initialize the UART
774 	 */
775 	outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR);	/* reset DLAB */
776 	info->MCR = UART_MCR_DTR | UART_MCR_RTS;
777 	outb(info->MCR, info->ioaddr + UART_MCR);
778 
779 	/*
780 	 * Finally, enable interrupts
781 	 */
782 	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
783 
784 	if (info->board->must_hwid)
785 		info->IER |= MOXA_MUST_IER_EGDAI;
786 	outb(info->IER, info->ioaddr + UART_IER);	/* enable interrupts */
787 
788 	/*
789 	 * And clear the interrupt registers again for luck.
790 	 */
791 	(void) inb(info->ioaddr + UART_LSR);
792 	(void) inb(info->ioaddr + UART_RX);
793 	(void) inb(info->ioaddr + UART_IIR);
794 	(void) inb(info->ioaddr + UART_MSR);
795 
796 	clear_bit(TTY_IO_ERROR, &tty->flags);
797 	kfifo_reset(&port->xmit_fifo);
798 
799 	/*
800 	 * and set the speed of the serial port
801 	 */
802 	mxser_change_speed(tty, NULL);
803 	spin_unlock_irqrestore(&info->slock, flags);
804 
805 	return 0;
806 err_free_xmit:
807 	tty_port_free_xmit_buf(port);
808 	return ret;
809 }
810 
811 /*
812  * To stop accepting input, we disable the receive line status interrupts, and
813  * tell the interrupt driver to stop checking the data ready bit in the line
814  * status register.
815  */
816 static void mxser_stop_rx(struct mxser_port *info)
817 {
818 	info->IER &= ~UART_IER_RLSI;
819 	if (info->board->must_hwid)
820 		info->IER &= ~MOXA_MUST_RECV_ISR;
821 
822 	outb(info->IER, info->ioaddr + UART_IER);
823 }
824 
825 /*
826  * This routine will shutdown a serial port
827  */
828 static void mxser_shutdown_port(struct tty_port *port)
829 {
830 	struct mxser_port *info = container_of(port, struct mxser_port, port);
831 	unsigned long flags;
832 
833 	spin_lock_irqsave(&info->slock, flags);
834 
835 	mxser_stop_rx(info);
836 
837 	/*
838 	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
839 	 * here so the queue might never be waken up
840 	 */
841 	wake_up_interruptible(&info->port.delta_msr_wait);
842 
843 	info->IER = 0;
844 	outb(0x00, info->ioaddr + UART_IER);
845 
846 	/* clear Rx/Tx FIFO's */
847 	mxser_disable_and_clear_FIFO(info);
848 
849 	/* read data port to reset things */
850 	(void) inb(info->ioaddr + UART_RX);
851 
852 
853 	if (info->board->must_hwid)
854 		mxser_must_no_sw_flow_control(info->ioaddr);
855 
856 	spin_unlock_irqrestore(&info->slock, flags);
857 
858 	/* make sure ISR is not running while we free the buffer */
859 	synchronize_irq(info->board->irq);
860 
861 	tty_port_free_xmit_buf(port);
862 }
863 
864 /*
865  * This routine is called whenever a serial port is opened.  It
866  * enables interrupts for a serial port, linking in its async structure into
867  * the IRQ chain.   It also performs the serial-specific
868  * initialization for the tty structure.
869  */
870 static int mxser_open(struct tty_struct *tty, struct file *filp)
871 {
872 	struct tty_port *tport = tty->port;
873 	struct mxser_port *port = container_of(tport, struct mxser_port, port);
874 
875 	tty->driver_data = port;
876 
877 	return tty_port_open(tport, tty, filp);
878 }
879 
880 static void mxser_flush_buffer(struct tty_struct *tty)
881 {
882 	struct mxser_port *info = tty->driver_data;
883 	unsigned long flags;
884 
885 	spin_lock_irqsave(&info->slock, flags);
886 	kfifo_reset(&info->port.xmit_fifo);
887 
888 	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
889 		info->ioaddr + UART_FCR);
890 
891 	spin_unlock_irqrestore(&info->slock, flags);
892 
893 	tty_wakeup(tty);
894 }
895 
896 static void mxser_close(struct tty_struct *tty, struct file *filp)
897 {
898 	tty_port_close(tty->port, tty, filp);
899 }
900 
901 static ssize_t mxser_write(struct tty_struct *tty, const u8 *buf, size_t count)
902 {
903 	struct mxser_port *info = tty->driver_data;
904 	unsigned long flags;
905 	size_t written;
906 	bool is_empty;
907 
908 	spin_lock_irqsave(&info->slock, flags);
909 	written = kfifo_in(&info->port.xmit_fifo, buf, count);
910 	is_empty = kfifo_is_empty(&info->port.xmit_fifo);
911 	spin_unlock_irqrestore(&info->slock, flags);
912 
913 	if (!is_empty && !tty->flow.stopped)
914 		if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
915 			mxser_start_tx(info);
916 
917 	return written;
918 }
919 
920 static int mxser_put_char(struct tty_struct *tty, u8 ch)
921 {
922 	struct mxser_port *info = tty->driver_data;
923 	unsigned long flags;
924 	int ret;
925 
926 	spin_lock_irqsave(&info->slock, flags);
927 	ret = kfifo_put(&info->port.xmit_fifo, ch);
928 	spin_unlock_irqrestore(&info->slock, flags);
929 
930 	return ret;
931 }
932 
933 
934 static void mxser_flush_chars(struct tty_struct *tty)
935 {
936 	struct mxser_port *info = tty->driver_data;
937 
938 	if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped ||
939 			(tty->hw_stopped && !mxser_16550A_or_MUST(info)))
940 		return;
941 
942 	mxser_start_tx(info);
943 }
944 
945 static unsigned int mxser_write_room(struct tty_struct *tty)
946 {
947 	struct mxser_port *info = tty->driver_data;
948 
949 	return kfifo_avail(&info->port.xmit_fifo);
950 }
951 
952 static unsigned int mxser_chars_in_buffer(struct tty_struct *tty)
953 {
954 	struct mxser_port *info = tty->driver_data;
955 
956 	return kfifo_len(&info->port.xmit_fifo);
957 }
958 
959 /*
960  * ------------------------------------------------------------
961  * friends of mxser_ioctl()
962  * ------------------------------------------------------------
963  */
964 static int mxser_get_serial_info(struct tty_struct *tty,
965 		struct serial_struct *ss)
966 {
967 	struct mxser_port *info = tty->driver_data;
968 	struct tty_port *port = &info->port;
969 	unsigned int closing_wait, close_delay;
970 
971 	mutex_lock(&port->mutex);
972 
973 	close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
974 	closing_wait = info->port.closing_wait;
975 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
976 		closing_wait = jiffies_to_msecs(closing_wait) / 10;
977 
978 	ss->type = info->type;
979 	ss->line = tty->index;
980 	ss->port = info->ioaddr;
981 	ss->irq = info->board->irq;
982 	ss->flags = info->port.flags;
983 	ss->baud_base = MXSER_BAUD_BASE;
984 	ss->close_delay = close_delay;
985 	ss->closing_wait = closing_wait;
986 	ss->custom_divisor = MXSER_CUSTOM_DIVISOR;
987 	mutex_unlock(&port->mutex);
988 	return 0;
989 }
990 
991 static int mxser_set_serial_info(struct tty_struct *tty,
992 		struct serial_struct *ss)
993 {
994 	struct mxser_port *info = tty->driver_data;
995 	struct tty_port *port = &info->port;
996 	speed_t baud;
997 	unsigned long sl_flags;
998 	unsigned int old_speed, close_delay, closing_wait;
999 	int retval = 0;
1000 
1001 	if (tty_io_error(tty))
1002 		return -EIO;
1003 
1004 	mutex_lock(&port->mutex);
1005 
1006 	if (ss->irq != info->board->irq ||
1007 			ss->port != info->ioaddr) {
1008 		mutex_unlock(&port->mutex);
1009 		return -EINVAL;
1010 	}
1011 
1012 	old_speed = port->flags & ASYNC_SPD_MASK;
1013 
1014 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
1015 	closing_wait = ss->closing_wait;
1016 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
1017 		closing_wait = msecs_to_jiffies(closing_wait * 10);
1018 
1019 	if (!capable(CAP_SYS_ADMIN)) {
1020 		if ((ss->baud_base != MXSER_BAUD_BASE) ||
1021 				(close_delay != port->close_delay) ||
1022 				(closing_wait != port->closing_wait) ||
1023 				((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) {
1024 			mutex_unlock(&port->mutex);
1025 			return -EPERM;
1026 		}
1027 		port->flags = (port->flags & ~ASYNC_USR_MASK) |
1028 				(ss->flags & ASYNC_USR_MASK);
1029 	} else {
1030 		/*
1031 		 * OK, past this point, all the error checking has been done.
1032 		 * At this point, we start making changes.....
1033 		 */
1034 		port->flags = ((port->flags & ~ASYNC_FLAGS) |
1035 				(ss->flags & ASYNC_FLAGS));
1036 		port->close_delay = close_delay;
1037 		port->closing_wait = closing_wait;
1038 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
1039 				(ss->baud_base != MXSER_BAUD_BASE ||
1040 				ss->custom_divisor !=
1041 				MXSER_CUSTOM_DIVISOR)) {
1042 			if (ss->custom_divisor == 0) {
1043 				mutex_unlock(&port->mutex);
1044 				return -EINVAL;
1045 			}
1046 			baud = ss->baud_base / ss->custom_divisor;
1047 			tty_encode_baud_rate(tty, baud, baud);
1048 		}
1049 
1050 		info->type = ss->type;
1051 
1052 		mxser_process_txrx_fifo(info);
1053 	}
1054 
1055 	if (tty_port_initialized(port)) {
1056 		if (old_speed != (port->flags & ASYNC_SPD_MASK)) {
1057 			spin_lock_irqsave(&info->slock, sl_flags);
1058 			mxser_change_speed(tty, NULL);
1059 			spin_unlock_irqrestore(&info->slock, sl_flags);
1060 		}
1061 	} else {
1062 		retval = mxser_activate(port, tty);
1063 		if (retval == 0)
1064 			tty_port_set_initialized(port, true);
1065 	}
1066 	mutex_unlock(&port->mutex);
1067 	return retval;
1068 }
1069 
1070 /*
1071  * mxser_get_lsr_info - get line status register info
1072  *
1073  * Purpose: Let user call ioctl() to get info when the UART physically
1074  *	    is emptied.  On bus types like RS485, the transmitter must
1075  *	    release the bus after transmitting. This must be done when
1076  *	    the transmit shift register is empty, not be done when the
1077  *	    transmit holding register is empty.  This functionality
1078  *	    allows an RS485 driver to be written in user space.
1079  */
1080 static int mxser_get_lsr_info(struct mxser_port *info,
1081 		unsigned int __user *value)
1082 {
1083 	unsigned char status;
1084 	unsigned int result;
1085 	unsigned long flags;
1086 
1087 	spin_lock_irqsave(&info->slock, flags);
1088 	status = inb(info->ioaddr + UART_LSR);
1089 	spin_unlock_irqrestore(&info->slock, flags);
1090 	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1091 	return put_user(result, value);
1092 }
1093 
1094 static int mxser_tiocmget(struct tty_struct *tty)
1095 {
1096 	struct mxser_port *info = tty->driver_data;
1097 	unsigned char control;
1098 	unsigned long flags;
1099 	u8 msr;
1100 
1101 	if (tty_io_error(tty))
1102 		return -EIO;
1103 
1104 	spin_lock_irqsave(&info->slock, flags);
1105 	control = info->MCR;
1106 	msr = mxser_check_modem_status(tty, info);
1107 	spin_unlock_irqrestore(&info->slock, flags);
1108 
1109 	return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
1110 		    ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
1111 		    ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |
1112 		    ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) |
1113 		    ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) |
1114 		    ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0);
1115 }
1116 
1117 static int mxser_tiocmset(struct tty_struct *tty,
1118 		unsigned int set, unsigned int clear)
1119 {
1120 	struct mxser_port *info = tty->driver_data;
1121 	unsigned long flags;
1122 
1123 	if (tty_io_error(tty))
1124 		return -EIO;
1125 
1126 	spin_lock_irqsave(&info->slock, flags);
1127 
1128 	if (set & TIOCM_RTS)
1129 		info->MCR |= UART_MCR_RTS;
1130 	if (set & TIOCM_DTR)
1131 		info->MCR |= UART_MCR_DTR;
1132 
1133 	if (clear & TIOCM_RTS)
1134 		info->MCR &= ~UART_MCR_RTS;
1135 	if (clear & TIOCM_DTR)
1136 		info->MCR &= ~UART_MCR_DTR;
1137 
1138 	outb(info->MCR, info->ioaddr + UART_MCR);
1139 	spin_unlock_irqrestore(&info->slock, flags);
1140 	return 0;
1141 }
1142 
1143 static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg,
1144 		struct async_icount *cprev)
1145 {
1146 	struct async_icount cnow;
1147 	unsigned long flags;
1148 	int ret;
1149 
1150 	spin_lock_irqsave(&info->slock, flags);
1151 	cnow = info->icount;	/* atomic copy */
1152 	spin_unlock_irqrestore(&info->slock, flags);
1153 
1154 	ret =	((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
1155 		((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
1156 		((arg & TIOCM_CD)  && (cnow.dcd != cprev->dcd)) ||
1157 		((arg & TIOCM_CTS) && (cnow.cts != cprev->cts));
1158 
1159 	*cprev = cnow;
1160 
1161 	return ret;
1162 }
1163 
1164 /* We should likely switch to TIOCGRS485/TIOCSRS485. */
1165 static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set,
1166 		int __user *u_opmode)
1167 {
1168 	int opmode, p = index % 4;
1169 	int shiftbit = p * 2;
1170 	u8 val;
1171 
1172 	if (port->board->must_hwid != MOXA_MUST_MU860_HWID)
1173 		return -EFAULT;
1174 
1175 	if (set) {
1176 		if (get_user(opmode, u_opmode))
1177 			return -EFAULT;
1178 
1179 		if (opmode & ~OP_MODE_MASK)
1180 			return -EINVAL;
1181 
1182 		spin_lock_irq(&port->slock);
1183 		val = inb(port->opmode_ioaddr);
1184 		val &= ~(OP_MODE_MASK << shiftbit);
1185 		val |= (opmode << shiftbit);
1186 		outb(val, port->opmode_ioaddr);
1187 		spin_unlock_irq(&port->slock);
1188 
1189 		return 0;
1190 	}
1191 
1192 	spin_lock_irq(&port->slock);
1193 	opmode = inb(port->opmode_ioaddr) >> shiftbit;
1194 	spin_unlock_irq(&port->slock);
1195 
1196 	return put_user(opmode & OP_MODE_MASK, u_opmode);
1197 }
1198 
1199 static int mxser_ioctl(struct tty_struct *tty,
1200 		unsigned int cmd, unsigned long arg)
1201 {
1202 	struct mxser_port *info = tty->driver_data;
1203 	struct async_icount cnow;
1204 	unsigned long flags;
1205 	void __user *argp = (void __user *)arg;
1206 
1207 	if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE)
1208 		return mxser_ioctl_op_mode(info, tty->index,
1209 				cmd == MOXA_SET_OP_MODE, argp);
1210 
1211 	if (cmd != TIOCMIWAIT && tty_io_error(tty))
1212 		return -EIO;
1213 
1214 	switch (cmd) {
1215 	case TIOCSERGETLSR:	/* Get line status register */
1216 		return  mxser_get_lsr_info(info, argp);
1217 		/*
1218 		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1219 		 * - mask passed in arg for lines of interest
1220 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1221 		 * Caller should use TIOCGICOUNT to see which one it was
1222 		 */
1223 	case TIOCMIWAIT:
1224 		spin_lock_irqsave(&info->slock, flags);
1225 		cnow = info->icount;	/* note the counters on entry */
1226 		spin_unlock_irqrestore(&info->slock, flags);
1227 
1228 		return wait_event_interruptible(info->port.delta_msr_wait,
1229 				mxser_cflags_changed(info, arg, &cnow));
1230 	default:
1231 		return -ENOIOCTLCMD;
1232 	}
1233 	return 0;
1234 }
1235 
1236 	/*
1237 	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1238 	 * Return: write counters to the user passed counter struct
1239 	 * NB: both 1->0 and 0->1 transitions are counted except for
1240 	 *     RI where only 0->1 is counted.
1241 	 */
1242 
1243 static int mxser_get_icount(struct tty_struct *tty,
1244 		struct serial_icounter_struct *icount)
1245 
1246 {
1247 	struct mxser_port *info = tty->driver_data;
1248 	struct async_icount cnow;
1249 	unsigned long flags;
1250 
1251 	spin_lock_irqsave(&info->slock, flags);
1252 	cnow = info->icount;
1253 	spin_unlock_irqrestore(&info->slock, flags);
1254 
1255 	icount->frame = cnow.frame;
1256 	icount->brk = cnow.brk;
1257 	icount->overrun = cnow.overrun;
1258 	icount->buf_overrun = cnow.buf_overrun;
1259 	icount->parity = cnow.parity;
1260 	icount->rx = cnow.rx;
1261 	icount->tx = cnow.tx;
1262 	icount->cts = cnow.cts;
1263 	icount->dsr = cnow.dsr;
1264 	icount->rng = cnow.rng;
1265 	icount->dcd = cnow.dcd;
1266 	return 0;
1267 }
1268 
1269 /*
1270  * This routine is called by the upper-layer tty layer to signal that
1271  * incoming characters should be throttled.
1272  */
1273 static void mxser_throttle(struct tty_struct *tty)
1274 {
1275 	struct mxser_port *info = tty->driver_data;
1276 
1277 	if (I_IXOFF(tty)) {
1278 		if (info->board->must_hwid) {
1279 			info->IER &= ~MOXA_MUST_RECV_ISR;
1280 			outb(info->IER, info->ioaddr + UART_IER);
1281 		} else {
1282 			info->x_char = STOP_CHAR(tty);
1283 			outb(0, info->ioaddr + UART_IER);
1284 			info->IER |= UART_IER_THRI;
1285 			outb(info->IER, info->ioaddr + UART_IER);
1286 		}
1287 	}
1288 
1289 	if (C_CRTSCTS(tty)) {
1290 		info->MCR &= ~UART_MCR_RTS;
1291 		outb(info->MCR, info->ioaddr + UART_MCR);
1292 	}
1293 }
1294 
1295 static void mxser_unthrottle(struct tty_struct *tty)
1296 {
1297 	struct mxser_port *info = tty->driver_data;
1298 
1299 	/* startrx */
1300 	if (I_IXOFF(tty)) {
1301 		if (info->x_char)
1302 			info->x_char = 0;
1303 		else {
1304 			if (info->board->must_hwid) {
1305 				info->IER |= MOXA_MUST_RECV_ISR;
1306 				outb(info->IER, info->ioaddr + UART_IER);
1307 			} else {
1308 				info->x_char = START_CHAR(tty);
1309 				outb(0, info->ioaddr + UART_IER);
1310 				info->IER |= UART_IER_THRI;
1311 				outb(info->IER, info->ioaddr + UART_IER);
1312 			}
1313 		}
1314 	}
1315 
1316 	if (C_CRTSCTS(tty)) {
1317 		info->MCR |= UART_MCR_RTS;
1318 		outb(info->MCR, info->ioaddr + UART_MCR);
1319 	}
1320 }
1321 
1322 /*
1323  * mxser_stop() and mxser_start()
1324  *
1325  * This routines are called before setting or resetting tty->flow.stopped.
1326  * They enable or disable transmitter interrupts, as necessary.
1327  */
1328 static void mxser_stop(struct tty_struct *tty)
1329 {
1330 	struct mxser_port *info = tty->driver_data;
1331 	unsigned long flags;
1332 
1333 	spin_lock_irqsave(&info->slock, flags);
1334 	if (info->IER & UART_IER_THRI)
1335 		__mxser_stop_tx(info);
1336 	spin_unlock_irqrestore(&info->slock, flags);
1337 }
1338 
1339 static void mxser_start(struct tty_struct *tty)
1340 {
1341 	struct mxser_port *info = tty->driver_data;
1342 	unsigned long flags;
1343 
1344 	spin_lock_irqsave(&info->slock, flags);
1345 	if (!kfifo_is_empty(&info->port.xmit_fifo))
1346 		__mxser_start_tx(info);
1347 	spin_unlock_irqrestore(&info->slock, flags);
1348 }
1349 
1350 static void mxser_set_termios(struct tty_struct *tty,
1351 			      const struct ktermios *old_termios)
1352 {
1353 	struct mxser_port *info = tty->driver_data;
1354 	unsigned long flags;
1355 
1356 	spin_lock_irqsave(&info->slock, flags);
1357 	mxser_change_speed(tty, old_termios);
1358 	spin_unlock_irqrestore(&info->slock, flags);
1359 
1360 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
1361 		tty->hw_stopped = false;
1362 		mxser_start(tty);
1363 	}
1364 
1365 	/* Handle sw stopped */
1366 	if ((old_termios->c_iflag & IXON) && !I_IXON(tty)) {
1367 		tty->flow.stopped = 0;
1368 
1369 		if (info->board->must_hwid) {
1370 			spin_lock_irqsave(&info->slock, flags);
1371 			mxser_must_set_rx_sw_flow_control(info->ioaddr, false);
1372 			spin_unlock_irqrestore(&info->slock, flags);
1373 		}
1374 
1375 		mxser_start(tty);
1376 	}
1377 }
1378 
1379 static bool mxser_tx_empty(struct mxser_port *info)
1380 {
1381 	unsigned long flags;
1382 	u8 lsr;
1383 
1384 	spin_lock_irqsave(&info->slock, flags);
1385 	lsr = inb(info->ioaddr + UART_LSR);
1386 	spin_unlock_irqrestore(&info->slock, flags);
1387 
1388 	return !(lsr & UART_LSR_TEMT);
1389 }
1390 
1391 /*
1392  * mxser_wait_until_sent() --- wait until the transmitter is empty
1393  */
1394 static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
1395 {
1396 	struct mxser_port *info = tty->driver_data;
1397 	unsigned long expire, char_time;
1398 
1399 	if (info->type == PORT_UNKNOWN)
1400 		return;
1401 
1402 	if (info->xmit_fifo_size == 0)
1403 		return;		/* Just in case.... */
1404 
1405 	/*
1406 	 * Set the check interval to be 1/5 of the estimated time to
1407 	 * send a single character, and make it at least 1.  The check
1408 	 * interval should also be less than the timeout.
1409 	 *
1410 	 * Note: we have to use pretty tight timings here to satisfy
1411 	 * the NIST-PCTS.
1412 	 */
1413 	char_time = (info->timeout - HZ / 50) / info->xmit_fifo_size;
1414 	char_time = char_time / 5;
1415 	if (char_time == 0)
1416 		char_time = 1;
1417 	if (timeout && timeout < char_time)
1418 		char_time = timeout;
1419 
1420 	char_time = jiffies_to_msecs(char_time);
1421 
1422 	/*
1423 	 * If the transmitter hasn't cleared in twice the approximate
1424 	 * amount of time to send the entire FIFO, it probably won't
1425 	 * ever clear.  This assumes the UART isn't doing flow
1426 	 * control, which is currently the case.  Hence, if it ever
1427 	 * takes longer than info->timeout, this is probably due to a
1428 	 * UART bug of some kind.  So, we clamp the timeout parameter at
1429 	 * 2*info->timeout.
1430 	 */
1431 	if (!timeout || timeout > 2 * info->timeout)
1432 		timeout = 2 * info->timeout;
1433 
1434 	expire = jiffies + timeout;
1435 
1436 	while (mxser_tx_empty(info)) {
1437 		msleep_interruptible(char_time);
1438 		if (signal_pending(current))
1439 			break;
1440 		if (time_after(jiffies, expire))
1441 			break;
1442 	}
1443 }
1444 
1445 /*
1446  * This routine is called by tty_hangup() when a hangup is signaled.
1447  */
1448 static void mxser_hangup(struct tty_struct *tty)
1449 {
1450 	struct mxser_port *info = tty->driver_data;
1451 
1452 	mxser_flush_buffer(tty);
1453 	tty_port_hangup(&info->port);
1454 }
1455 
1456 /*
1457  * mxser_rs_break() --- routine which turns the break handling on or off
1458  */
1459 static int mxser_rs_break(struct tty_struct *tty, int break_state)
1460 {
1461 	struct mxser_port *info = tty->driver_data;
1462 	unsigned long flags;
1463 	u8 lcr;
1464 
1465 	spin_lock_irqsave(&info->slock, flags);
1466 	lcr = inb(info->ioaddr + UART_LCR);
1467 	if (break_state == -1)
1468 		lcr |= UART_LCR_SBC;
1469 	else
1470 		lcr &= ~UART_LCR_SBC;
1471 	outb(lcr, info->ioaddr + UART_LCR);
1472 	spin_unlock_irqrestore(&info->slock, flags);
1473 
1474 	return 0;
1475 }
1476 
1477 static bool mxser_receive_chars_new(struct mxser_port *port, u8 status)
1478 {
1479 	enum mxser_must_hwid hwid = port->board->must_hwid;
1480 	u8 gdl;
1481 
1482 	if (hwid == MOXA_OTHER_UART)
1483 		return false;
1484 	if (status & (UART_LSR_BRK_ERROR_BITS | MOXA_MUST_LSR_RERR))
1485 		return false;
1486 
1487 	gdl = inb(port->ioaddr + MOXA_MUST_GDL_REGISTER);
1488 	if (hwid == MOXA_MUST_MU150_HWID)
1489 		gdl &= MOXA_MUST_GDL_MASK;
1490 
1491 	while (gdl--) {
1492 		u8 ch = inb(port->ioaddr + UART_RX);
1493 		if (!tty_insert_flip_char(&port->port, ch, 0))
1494 			port->icount.buf_overrun++;
1495 	}
1496 
1497 	return true;
1498 }
1499 
1500 static u8 mxser_receive_chars_old(struct tty_struct *tty,
1501 		                struct mxser_port *port, u8 status)
1502 {
1503 	enum mxser_must_hwid hwid = port->board->must_hwid;
1504 	int ignored = 0;
1505 	int max = 256;
1506 	u8 ch;
1507 
1508 	do {
1509 		if (max-- < 0)
1510 			break;
1511 
1512 		ch = inb(port->ioaddr + UART_RX);
1513 		if (hwid && (status & UART_LSR_OE))
1514 			outb(port->FCR | UART_FCR_CLEAR_RCVR,
1515 					port->ioaddr + UART_FCR);
1516 		status &= port->read_status_mask;
1517 		if (status & port->ignore_status_mask) {
1518 			if (++ignored > 100)
1519 				break;
1520 		} else {
1521 			u8 flag = 0;
1522 			if (status & UART_LSR_BRK_ERROR_BITS) {
1523 				if (status & UART_LSR_BI) {
1524 					flag = TTY_BREAK;
1525 					port->icount.brk++;
1526 
1527 					if (port->port.flags & ASYNC_SAK)
1528 						do_SAK(tty);
1529 				} else if (status & UART_LSR_PE) {
1530 					flag = TTY_PARITY;
1531 					port->icount.parity++;
1532 				} else if (status & UART_LSR_FE) {
1533 					flag = TTY_FRAME;
1534 					port->icount.frame++;
1535 				} else if (status & UART_LSR_OE) {
1536 					flag = TTY_OVERRUN;
1537 					port->icount.overrun++;
1538 				}
1539 			}
1540 			if (!tty_insert_flip_char(&port->port, ch, flag)) {
1541 				port->icount.buf_overrun++;
1542 				break;
1543 			}
1544 		}
1545 
1546 		if (hwid)
1547 			break;
1548 
1549 		status = inb(port->ioaddr + UART_LSR);
1550 	} while (status & UART_LSR_DR);
1551 
1552 	return status;
1553 }
1554 
1555 static u8 mxser_receive_chars(struct tty_struct *tty,
1556 		struct mxser_port *port, u8 status)
1557 {
1558 	if (!mxser_receive_chars_new(port, status))
1559 		status = mxser_receive_chars_old(tty, port, status);
1560 
1561 	tty_flip_buffer_push(&port->port);
1562 
1563 	return status;
1564 }
1565 
1566 static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port)
1567 {
1568 	int count;
1569 
1570 	if (port->x_char) {
1571 		outb(port->x_char, port->ioaddr + UART_TX);
1572 		port->x_char = 0;
1573 		port->icount.tx++;
1574 		return;
1575 	}
1576 
1577 	if (kfifo_is_empty(&port->port.xmit_fifo) || tty->flow.stopped ||
1578 			(tty->hw_stopped && !mxser_16550A_or_MUST(port))) {
1579 		__mxser_stop_tx(port);
1580 		return;
1581 	}
1582 
1583 	count = port->xmit_fifo_size;
1584 	do {
1585 		u8 c;
1586 
1587 		if (!kfifo_get(&port->port.xmit_fifo, &c))
1588 			break;
1589 
1590 		outb(c, port->ioaddr + UART_TX);
1591 		port->icount.tx++;
1592 	} while (--count > 0);
1593 
1594 	if (kfifo_len(&port->port.xmit_fifo) < WAKEUP_CHARS)
1595 		tty_wakeup(tty);
1596 
1597 	if (kfifo_is_empty(&port->port.xmit_fifo))
1598 		__mxser_stop_tx(port);
1599 }
1600 
1601 static bool mxser_port_isr(struct mxser_port *port)
1602 {
1603 	struct tty_struct *tty;
1604 	u8 iir, status;
1605 	bool error = false;
1606 
1607 	iir = inb(port->ioaddr + UART_IIR);
1608 	if (iir & UART_IIR_NO_INT)
1609 		return true;
1610 
1611 	iir &= MOXA_MUST_IIR_MASK;
1612 	tty = tty_port_tty_get(&port->port);
1613 	if (!tty) {
1614 		status = inb(port->ioaddr + UART_LSR);
1615 		outb(port->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
1616 				port->ioaddr + UART_FCR);
1617 		inb(port->ioaddr + UART_MSR);
1618 
1619 		error = true;
1620 		goto put_tty;
1621 	}
1622 
1623 	status = inb(port->ioaddr + UART_LSR);
1624 
1625 	if (port->board->must_hwid) {
1626 		if (iir == MOXA_MUST_IIR_GDA ||
1627 		    iir == MOXA_MUST_IIR_RDA ||
1628 		    iir == MOXA_MUST_IIR_RTO ||
1629 		    iir == MOXA_MUST_IIR_LSR)
1630 			status = mxser_receive_chars(tty, port, status);
1631 	} else {
1632 		status &= port->read_status_mask;
1633 		if (status & UART_LSR_DR)
1634 			status = mxser_receive_chars(tty, port, status);
1635 	}
1636 
1637 	mxser_check_modem_status(tty, port);
1638 
1639 	if (port->board->must_hwid) {
1640 		if (iir == 0x02 && (status & UART_LSR_THRE))
1641 			mxser_transmit_chars(tty, port);
1642 	} else {
1643 		if (status & UART_LSR_THRE)
1644 			mxser_transmit_chars(tty, port);
1645 	}
1646 
1647 put_tty:
1648 	tty_kref_put(tty);
1649 
1650 	return error;
1651 }
1652 
1653 /*
1654  * This is the serial driver's generic interrupt routine
1655  */
1656 static irqreturn_t mxser_interrupt(int irq, void *dev_id)
1657 {
1658 	struct mxser_board *brd = dev_id;
1659 	struct mxser_port *port;
1660 	unsigned int int_cnt, pass_counter = 0;
1661 	unsigned int i, max = brd->nports;
1662 	int handled = IRQ_NONE;
1663 	u8 irqbits, bits, mask = BIT(max) - 1;
1664 
1665 	while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
1666 		irqbits = inb(brd->vector) & mask;
1667 		if (irqbits == mask)
1668 			break;
1669 
1670 		handled = IRQ_HANDLED;
1671 		for (i = 0, bits = 1; i < max; i++, irqbits |= bits, bits <<= 1) {
1672 			if (irqbits == mask)
1673 				break;
1674 			if (bits & irqbits)
1675 				continue;
1676 			port = &brd->ports[i];
1677 
1678 			int_cnt = 0;
1679 			spin_lock(&port->slock);
1680 			do {
1681 				if (mxser_port_isr(port))
1682 					break;
1683 			} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
1684 			spin_unlock(&port->slock);
1685 		}
1686 	}
1687 
1688 	return handled;
1689 }
1690 
1691 static const struct tty_operations mxser_ops = {
1692 	.open = mxser_open,
1693 	.close = mxser_close,
1694 	.write = mxser_write,
1695 	.put_char = mxser_put_char,
1696 	.flush_chars = mxser_flush_chars,
1697 	.write_room = mxser_write_room,
1698 	.chars_in_buffer = mxser_chars_in_buffer,
1699 	.flush_buffer = mxser_flush_buffer,
1700 	.ioctl = mxser_ioctl,
1701 	.throttle = mxser_throttle,
1702 	.unthrottle = mxser_unthrottle,
1703 	.set_termios = mxser_set_termios,
1704 	.stop = mxser_stop,
1705 	.start = mxser_start,
1706 	.hangup = mxser_hangup,
1707 	.break_ctl = mxser_rs_break,
1708 	.wait_until_sent = mxser_wait_until_sent,
1709 	.tiocmget = mxser_tiocmget,
1710 	.tiocmset = mxser_tiocmset,
1711 	.set_serial = mxser_set_serial_info,
1712 	.get_serial = mxser_get_serial_info,
1713 	.get_icount = mxser_get_icount,
1714 };
1715 
1716 static const struct tty_port_operations mxser_port_ops = {
1717 	.carrier_raised = mxser_carrier_raised,
1718 	.dtr_rts = mxser_dtr_rts,
1719 	.activate = mxser_activate,
1720 	.shutdown = mxser_shutdown_port,
1721 };
1722 
1723 /*
1724  * The MOXA Smartio/Industio serial driver boot-time initialization code!
1725  */
1726 
1727 static void mxser_initbrd(struct mxser_board *brd, bool high_baud)
1728 {
1729 	struct mxser_port *info;
1730 	unsigned int i;
1731 	bool is_mu860;
1732 
1733 	brd->must_hwid = mxser_must_get_hwid(brd->ports[0].ioaddr);
1734 	is_mu860 = brd->must_hwid == MOXA_MUST_MU860_HWID;
1735 
1736 	for (i = 0; i < UART_INFO_NUM; i++) {
1737 		if (Gpci_uart_info[i].type == brd->must_hwid) {
1738 			brd->max_baud = Gpci_uart_info[i].max_baud;
1739 
1740 			/* exception....CP-102 */
1741 			if (high_baud)
1742 				brd->max_baud = 921600;
1743 			break;
1744 		}
1745 	}
1746 
1747 	if (is_mu860) {
1748 		/* set to RS232 mode by default */
1749 		outb(0, brd->vector + 4);
1750 		outb(0, brd->vector + 0x0c);
1751 	}
1752 
1753 	for (i = 0; i < brd->nports; i++) {
1754 		info = &brd->ports[i];
1755 		if (is_mu860) {
1756 			if (i < 4)
1757 				info->opmode_ioaddr = brd->vector + 4;
1758 			else
1759 				info->opmode_ioaddr = brd->vector + 0x0c;
1760 		}
1761 		tty_port_init(&info->port);
1762 		info->port.ops = &mxser_port_ops;
1763 		info->board = brd;
1764 
1765 		/* Enhance mode enabled here */
1766 		if (brd->must_hwid != MOXA_OTHER_UART)
1767 			mxser_must_set_enhance_mode(info->ioaddr, true);
1768 
1769 		info->type = PORT_16550A;
1770 
1771 		mxser_process_txrx_fifo(info);
1772 
1773 		spin_lock_init(&info->slock);
1774 
1775 		/* before set INT ISR, disable all int */
1776 		outb(inb(info->ioaddr + UART_IER) & 0xf0,
1777 			info->ioaddr + UART_IER);
1778 	}
1779 }
1780 
1781 static int mxser_probe(struct pci_dev *pdev,
1782 		const struct pci_device_id *ent)
1783 {
1784 	struct mxser_board *brd;
1785 	unsigned int i, base;
1786 	unsigned long ioaddress;
1787 	unsigned short nports = MXSER_NPORTS(ent->driver_data);
1788 	struct device *tty_dev;
1789 	int retval = -EINVAL;
1790 
1791 	i = find_first_zero_bit(mxser_boards, MXSER_BOARDS);
1792 	if (i >= MXSER_BOARDS) {
1793 		dev_err(&pdev->dev, "too many boards found (maximum %d), board "
1794 				"not configured\n", MXSER_BOARDS);
1795 		goto err;
1796 	}
1797 
1798 	brd = devm_kzalloc(&pdev->dev, struct_size(brd, ports, nports),
1799 			GFP_KERNEL);
1800 	if (!brd)
1801 		goto err;
1802 
1803 	brd->idx = i;
1804 	__set_bit(brd->idx, mxser_boards);
1805 	base = i * MXSER_PORTS_PER_BOARD;
1806 
1807 	retval = pcim_enable_device(pdev);
1808 	if (retval) {
1809 		dev_err(&pdev->dev, "PCI enable failed\n");
1810 		goto err_zero;
1811 	}
1812 
1813 	/* io address */
1814 	ioaddress = pci_resource_start(pdev, 2);
1815 	retval = pci_request_region(pdev, 2, "mxser(IO)");
1816 	if (retval)
1817 		goto err_zero;
1818 
1819 	brd->nports = nports;
1820 	for (i = 0; i < nports; i++)
1821 		brd->ports[i].ioaddr = ioaddress + 8 * i;
1822 
1823 	/* vector */
1824 	ioaddress = pci_resource_start(pdev, 3);
1825 	retval = pci_request_region(pdev, 3, "mxser(vector)");
1826 	if (retval)
1827 		goto err_zero;
1828 	brd->vector = ioaddress;
1829 
1830 	/* irq */
1831 	brd->irq = pdev->irq;
1832 
1833 	mxser_initbrd(brd, ent->driver_data & MXSER_HIGHBAUD);
1834 
1835 	retval = devm_request_irq(&pdev->dev, brd->irq, mxser_interrupt,
1836 			IRQF_SHARED, "mxser", brd);
1837 	if (retval) {
1838 		dev_err(&pdev->dev, "request irq failed");
1839 		goto err_relbrd;
1840 	}
1841 
1842 	for (i = 0; i < nports; i++) {
1843 		tty_dev = tty_port_register_device(&brd->ports[i].port,
1844 				mxvar_sdriver, base + i, &pdev->dev);
1845 		if (IS_ERR(tty_dev)) {
1846 			retval = PTR_ERR(tty_dev);
1847 			for (; i > 0; i--)
1848 				tty_unregister_device(mxvar_sdriver,
1849 					base + i - 1);
1850 			goto err_relbrd;
1851 		}
1852 	}
1853 
1854 	pci_set_drvdata(pdev, brd);
1855 
1856 	return 0;
1857 err_relbrd:
1858 	for (i = 0; i < nports; i++)
1859 		tty_port_destroy(&brd->ports[i].port);
1860 err_zero:
1861 	__clear_bit(brd->idx, mxser_boards);
1862 err:
1863 	return retval;
1864 }
1865 
1866 static void mxser_remove(struct pci_dev *pdev)
1867 {
1868 	struct mxser_board *brd = pci_get_drvdata(pdev);
1869 	unsigned int i, base = brd->idx * MXSER_PORTS_PER_BOARD;
1870 
1871 	for (i = 0; i < brd->nports; i++) {
1872 		tty_unregister_device(mxvar_sdriver, base + i);
1873 		tty_port_destroy(&brd->ports[i].port);
1874 	}
1875 
1876 	__clear_bit(brd->idx, mxser_boards);
1877 }
1878 
1879 static struct pci_driver mxser_driver = {
1880 	.name = "mxser",
1881 	.id_table = mxser_pcibrds,
1882 	.probe = mxser_probe,
1883 	.remove = mxser_remove
1884 };
1885 
1886 static int __init mxser_module_init(void)
1887 {
1888 	int retval;
1889 
1890 	mxvar_sdriver = tty_alloc_driver(MXSER_PORTS, TTY_DRIVER_REAL_RAW |
1891 			TTY_DRIVER_DYNAMIC_DEV);
1892 	if (IS_ERR(mxvar_sdriver))
1893 		return PTR_ERR(mxvar_sdriver);
1894 
1895 	/* Initialize the tty_driver structure */
1896 	mxvar_sdriver->name = "ttyMI";
1897 	mxvar_sdriver->major = ttymajor;
1898 	mxvar_sdriver->minor_start = 0;
1899 	mxvar_sdriver->type = TTY_DRIVER_TYPE_SERIAL;
1900 	mxvar_sdriver->subtype = SERIAL_TYPE_NORMAL;
1901 	mxvar_sdriver->init_termios = tty_std_termios;
1902 	mxvar_sdriver->init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
1903 	tty_set_operations(mxvar_sdriver, &mxser_ops);
1904 
1905 	retval = tty_register_driver(mxvar_sdriver);
1906 	if (retval) {
1907 		printk(KERN_ERR "Couldn't install MOXA Smartio/Industio family "
1908 				"tty driver !\n");
1909 		goto err_put;
1910 	}
1911 
1912 	retval = pci_register_driver(&mxser_driver);
1913 	if (retval) {
1914 		printk(KERN_ERR "mxser: can't register pci driver\n");
1915 		goto err_unr;
1916 	}
1917 
1918 	return 0;
1919 err_unr:
1920 	tty_unregister_driver(mxvar_sdriver);
1921 err_put:
1922 	tty_driver_kref_put(mxvar_sdriver);
1923 	return retval;
1924 }
1925 
1926 static void __exit mxser_module_exit(void)
1927 {
1928 	pci_unregister_driver(&mxser_driver);
1929 	tty_unregister_driver(mxvar_sdriver);
1930 	tty_driver_kref_put(mxvar_sdriver);
1931 }
1932 
1933 module_init(mxser_module_init);
1934 module_exit(mxser_module_exit);
1935