xref: /linux/drivers/tty/mxser.c (revision b48b89f9c189d24eb5e2b4a0ac067da5a24ee86d)
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 ((hwid = 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 int mxser_carrier_raised(struct tty_port *port)
462 {
463 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
464 	return (inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD)?1:0;
465 }
466 
467 static void mxser_dtr_rts(struct tty_port *port, int on)
468 {
469 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
470 	unsigned long flags;
471 	u8 mcr;
472 
473 	spin_lock_irqsave(&mp->slock, flags);
474 	mcr = inb(mp->ioaddr + UART_MCR);
475 	if (on)
476 		mcr |= UART_MCR_DTR | UART_MCR_RTS;
477 	else
478 		mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
479 	outb(mcr, mp->ioaddr + UART_MCR);
480 	spin_unlock_irqrestore(&mp->slock, flags);
481 }
482 
483 static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
484 {
485 	struct mxser_port *info = tty->driver_data;
486 	unsigned int quot = 0, baud;
487 	unsigned char cval;
488 	u64 timeout;
489 
490 	if (newspd > info->board->max_baud)
491 		return -1;
492 
493 	if (newspd == 134) {
494 		quot = 2 * MXSER_BAUD_BASE / 269;
495 		tty_encode_baud_rate(tty, 134, 134);
496 	} else if (newspd) {
497 		quot = MXSER_BAUD_BASE / newspd;
498 		if (quot == 0)
499 			quot = 1;
500 		baud = MXSER_BAUD_BASE / quot;
501 		tty_encode_baud_rate(tty, baud, baud);
502 	} else {
503 		quot = 0;
504 	}
505 
506 	/*
507 	 * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the
508 	 * u64 domain
509 	 */
510 	timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot;
511 	do_div(timeout, MXSER_BAUD_BASE);
512 	info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */
513 
514 	if (quot) {
515 		info->MCR |= UART_MCR_DTR;
516 		outb(info->MCR, info->ioaddr + UART_MCR);
517 	} else {
518 		info->MCR &= ~UART_MCR_DTR;
519 		outb(info->MCR, info->ioaddr + UART_MCR);
520 		return 0;
521 	}
522 
523 	cval = inb(info->ioaddr + UART_LCR);
524 
525 	outb(cval | UART_LCR_DLAB, info->ioaddr + UART_LCR);	/* set DLAB */
526 
527 	outb(quot & 0xff, info->ioaddr + UART_DLL);	/* LS of divisor */
528 	outb(quot >> 8, info->ioaddr + UART_DLM);	/* MS of divisor */
529 	outb(cval, info->ioaddr + UART_LCR);	/* reset DLAB */
530 
531 	if (C_BAUD(tty) == BOTHER) {
532 		quot = MXSER_BAUD_BASE % newspd;
533 		quot *= 8;
534 		if (quot % newspd > newspd / 2) {
535 			quot /= newspd;
536 			quot++;
537 		} else
538 			quot /= newspd;
539 
540 		mxser_set_must_enum_value(info->ioaddr, quot);
541 	} else {
542 		mxser_set_must_enum_value(info->ioaddr, 0);
543 	}
544 
545 	return 0;
546 }
547 
548 static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
549 		u8 msr)
550 {
551 	bool cts = msr & UART_MSR_CTS;
552 
553 	if (tty->hw_stopped) {
554 		if (cts) {
555 			tty->hw_stopped = 0;
556 
557 			if (!mxser_16550A_or_MUST(info))
558 				__mxser_start_tx(info);
559 			tty_wakeup(tty);
560 		}
561 		return;
562 	} else if (cts)
563 		return;
564 
565 	tty->hw_stopped = 1;
566 	if (!mxser_16550A_or_MUST(info))
567 		__mxser_stop_tx(info);
568 }
569 
570 /*
571  * This routine is called to set the UART divisor registers to match
572  * the specified baud rate for a serial port.
573  */
574 static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_termios)
575 {
576 	struct mxser_port *info = tty->driver_data;
577 	unsigned cflag, cval;
578 
579 	cflag = tty->termios.c_cflag;
580 
581 	if (mxser_set_baud(tty, tty_get_baud_rate(tty))) {
582 		/* Use previous rate on a failure */
583 		if (old_termios) {
584 			speed_t baud = tty_termios_baud_rate(old_termios);
585 			tty_encode_baud_rate(tty, baud, baud);
586 		}
587 	}
588 
589 	/* byte size and parity */
590 	cval = UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
591 
592 	if (cflag & CSTOPB)
593 		cval |= UART_LCR_STOP;
594 	if (cflag & PARENB)
595 		cval |= UART_LCR_PARITY;
596 	if (!(cflag & PARODD))
597 		cval |= UART_LCR_EPAR;
598 	if (cflag & CMSPAR)
599 		cval |= UART_LCR_SPAR;
600 
601 	info->FCR = 0;
602 	if (info->board->must_hwid) {
603 		info->FCR |= UART_FCR_ENABLE_FIFO |
604 			MOXA_MUST_FCR_GDA_MODE_ENABLE;
605 		mxser_set_must_fifo_value(info);
606 	} else if (info->type != PORT_8250 && info->type != PORT_16450) {
607 		info->FCR |= UART_FCR_ENABLE_FIFO;
608 		switch (info->rx_high_water) {
609 		case 1:
610 			info->FCR |= UART_FCR_TRIGGER_1;
611 			break;
612 		case 4:
613 			info->FCR |= UART_FCR_TRIGGER_4;
614 			break;
615 		case 8:
616 			info->FCR |= UART_FCR_TRIGGER_8;
617 			break;
618 		default:
619 			info->FCR |= UART_FCR_TRIGGER_14;
620 			break;
621 		}
622 	}
623 
624 	/* CTS flow control flag and modem status interrupts */
625 	info->IER &= ~UART_IER_MSI;
626 	info->MCR &= ~UART_MCR_AFE;
627 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
628 	if (cflag & CRTSCTS) {
629 		info->IER |= UART_IER_MSI;
630 		if (mxser_16550A_or_MUST(info)) {
631 			info->MCR |= UART_MCR_AFE;
632 		} else {
633 			mxser_handle_cts(tty, info,
634 					inb(info->ioaddr + UART_MSR));
635 		}
636 	}
637 	outb(info->MCR, info->ioaddr + UART_MCR);
638 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
639 	if (~cflag & CLOCAL)
640 		info->IER |= UART_IER_MSI;
641 	outb(info->IER, info->ioaddr + UART_IER);
642 
643 	/*
644 	 * Set up parity check flag
645 	 */
646 	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
647 	if (I_INPCK(tty))
648 		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
649 	if (I_BRKINT(tty) || I_PARMRK(tty))
650 		info->read_status_mask |= UART_LSR_BI;
651 
652 	info->ignore_status_mask = 0;
653 
654 	if (I_IGNBRK(tty)) {
655 		info->ignore_status_mask |= UART_LSR_BI;
656 		info->read_status_mask |= UART_LSR_BI;
657 		/*
658 		 * If we're ignore parity and break indicators, ignore
659 		 * overruns too.  (For real raw support).
660 		 */
661 		if (I_IGNPAR(tty)) {
662 			info->ignore_status_mask |=
663 						UART_LSR_OE |
664 						UART_LSR_PE |
665 						UART_LSR_FE;
666 			info->read_status_mask |=
667 						UART_LSR_OE |
668 						UART_LSR_PE |
669 						UART_LSR_FE;
670 		}
671 	}
672 	if (info->board->must_hwid) {
673 		mxser_set_must_xon1_value(info->ioaddr, START_CHAR(tty));
674 		mxser_set_must_xoff1_value(info->ioaddr, STOP_CHAR(tty));
675 		mxser_must_set_rx_sw_flow_control(info->ioaddr, I_IXON(tty));
676 		mxser_must_set_tx_sw_flow_control(info->ioaddr, I_IXOFF(tty));
677 	}
678 
679 
680 	outb(info->FCR, info->ioaddr + UART_FCR);
681 	outb(cval, info->ioaddr + UART_LCR);
682 }
683 
684 static u8 mxser_check_modem_status(struct tty_struct *tty,
685 				struct mxser_port *port)
686 {
687 	u8 msr = inb(port->ioaddr + UART_MSR);
688 
689 	if (!(msr & UART_MSR_ANY_DELTA))
690 		return msr;
691 
692 	/* update input line counters */
693 	if (msr & UART_MSR_TERI)
694 		port->icount.rng++;
695 	if (msr & UART_MSR_DDSR)
696 		port->icount.dsr++;
697 	if (msr & UART_MSR_DDCD)
698 		port->icount.dcd++;
699 	if (msr & UART_MSR_DCTS)
700 		port->icount.cts++;
701 	wake_up_interruptible(&port->port.delta_msr_wait);
702 
703 	if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) {
704 		if (msr & UART_MSR_DCD)
705 			wake_up_interruptible(&port->port.open_wait);
706 	}
707 
708 	if (tty_port_cts_enabled(&port->port))
709 		mxser_handle_cts(tty, port, msr);
710 
711 	return msr;
712 }
713 
714 static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
715 {
716 	u8 fcr = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
717 
718 	if (info->board->must_hwid)
719 		fcr |= MOXA_MUST_FCR_GDA_MODE_ENABLE;
720 
721 	outb(fcr, info->ioaddr + UART_FCR);
722 }
723 
724 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
725 {
726 	struct mxser_port *info = container_of(port, struct mxser_port, port);
727 	unsigned long flags;
728 	int ret;
729 
730 	ret = tty_port_alloc_xmit_buf(port);
731 	if (ret < 0)
732 		return ret;
733 
734 	spin_lock_irqsave(&info->slock, flags);
735 
736 	if (!info->type) {
737 		set_bit(TTY_IO_ERROR, &tty->flags);
738 		spin_unlock_irqrestore(&info->slock, flags);
739 		ret = 0;
740 		goto err_free_xmit;
741 	}
742 
743 	/*
744 	 * Clear the FIFO buffers and disable them
745 	 * (they will be reenabled in mxser_change_speed())
746 	 */
747 	mxser_disable_and_clear_FIFO(info);
748 
749 	/*
750 	 * At this point there's no way the LSR could still be 0xFF;
751 	 * if it is, then bail out, because there's likely no UART
752 	 * here.
753 	 */
754 	if (inb(info->ioaddr + UART_LSR) == 0xff) {
755 		spin_unlock_irqrestore(&info->slock, flags);
756 		if (capable(CAP_SYS_ADMIN)) {
757 			set_bit(TTY_IO_ERROR, &tty->flags);
758 			return 0;
759 		}
760 
761 		ret = -ENODEV;
762 		goto err_free_xmit;
763 	}
764 
765 	/*
766 	 * Clear the interrupt registers.
767 	 */
768 	(void) inb(info->ioaddr + UART_LSR);
769 	(void) inb(info->ioaddr + UART_RX);
770 	(void) inb(info->ioaddr + UART_IIR);
771 	(void) inb(info->ioaddr + UART_MSR);
772 
773 	/*
774 	 * Now, initialize the UART
775 	 */
776 	outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR);	/* reset DLAB */
777 	info->MCR = UART_MCR_DTR | UART_MCR_RTS;
778 	outb(info->MCR, info->ioaddr + UART_MCR);
779 
780 	/*
781 	 * Finally, enable interrupts
782 	 */
783 	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
784 
785 	if (info->board->must_hwid)
786 		info->IER |= MOXA_MUST_IER_EGDAI;
787 	outb(info->IER, info->ioaddr + UART_IER);	/* enable interrupts */
788 
789 	/*
790 	 * And clear the interrupt registers again for luck.
791 	 */
792 	(void) inb(info->ioaddr + UART_LSR);
793 	(void) inb(info->ioaddr + UART_RX);
794 	(void) inb(info->ioaddr + UART_IIR);
795 	(void) inb(info->ioaddr + UART_MSR);
796 
797 	clear_bit(TTY_IO_ERROR, &tty->flags);
798 	kfifo_reset(&port->xmit_fifo);
799 
800 	/*
801 	 * and set the speed of the serial port
802 	 */
803 	mxser_change_speed(tty, NULL);
804 	spin_unlock_irqrestore(&info->slock, flags);
805 
806 	return 0;
807 err_free_xmit:
808 	tty_port_free_xmit_buf(port);
809 	return ret;
810 }
811 
812 /*
813  * To stop accepting input, we disable the receive line status interrupts, and
814  * tell the interrupt driver to stop checking the data ready bit in the line
815  * status register.
816  */
817 static void mxser_stop_rx(struct mxser_port *info)
818 {
819 	info->IER &= ~UART_IER_RLSI;
820 	if (info->board->must_hwid)
821 		info->IER &= ~MOXA_MUST_RECV_ISR;
822 
823 	outb(info->IER, info->ioaddr + UART_IER);
824 }
825 
826 /*
827  * This routine will shutdown a serial port
828  */
829 static void mxser_shutdown_port(struct tty_port *port)
830 {
831 	struct mxser_port *info = container_of(port, struct mxser_port, port);
832 	unsigned long flags;
833 
834 	spin_lock_irqsave(&info->slock, flags);
835 
836 	mxser_stop_rx(info);
837 
838 	/*
839 	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
840 	 * here so the queue might never be waken up
841 	 */
842 	wake_up_interruptible(&info->port.delta_msr_wait);
843 
844 	info->IER = 0;
845 	outb(0x00, info->ioaddr + UART_IER);
846 
847 	/* clear Rx/Tx FIFO's */
848 	mxser_disable_and_clear_FIFO(info);
849 
850 	/* read data port to reset things */
851 	(void) inb(info->ioaddr + UART_RX);
852 
853 
854 	if (info->board->must_hwid)
855 		mxser_must_no_sw_flow_control(info->ioaddr);
856 
857 	spin_unlock_irqrestore(&info->slock, flags);
858 
859 	/* make sure ISR is not running while we free the buffer */
860 	synchronize_irq(info->board->irq);
861 
862 	tty_port_free_xmit_buf(port);
863 }
864 
865 /*
866  * This routine is called whenever a serial port is opened.  It
867  * enables interrupts for a serial port, linking in its async structure into
868  * the IRQ chain.   It also performs the serial-specific
869  * initialization for the tty structure.
870  */
871 static int mxser_open(struct tty_struct *tty, struct file *filp)
872 {
873 	struct tty_port *tport = tty->port;
874 	struct mxser_port *port = container_of(tport, struct mxser_port, port);
875 
876 	tty->driver_data = port;
877 
878 	return tty_port_open(tport, tty, filp);
879 }
880 
881 static void mxser_flush_buffer(struct tty_struct *tty)
882 {
883 	struct mxser_port *info = tty->driver_data;
884 	unsigned long flags;
885 
886 	spin_lock_irqsave(&info->slock, flags);
887 	kfifo_reset(&info->port.xmit_fifo);
888 
889 	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
890 		info->ioaddr + UART_FCR);
891 
892 	spin_unlock_irqrestore(&info->slock, flags);
893 
894 	tty_wakeup(tty);
895 }
896 
897 static void mxser_close(struct tty_struct *tty, struct file *filp)
898 {
899 	tty_port_close(tty->port, tty, filp);
900 }
901 
902 static int mxser_write(struct tty_struct *tty, const unsigned char *buf, int count)
903 {
904 	struct mxser_port *info = tty->driver_data;
905 	unsigned long flags;
906 	int written;
907 	bool is_empty;
908 
909 	spin_lock_irqsave(&info->slock, flags);
910 	written = kfifo_in(&info->port.xmit_fifo, buf, count);
911 	is_empty = kfifo_is_empty(&info->port.xmit_fifo);
912 	spin_unlock_irqrestore(&info->slock, flags);
913 
914 	if (!is_empty && !tty->flow.stopped)
915 		if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
916 			mxser_start_tx(info);
917 
918 	return written;
919 }
920 
921 static int mxser_put_char(struct tty_struct *tty, unsigned char ch)
922 {
923 	struct mxser_port *info = tty->driver_data;
924 	unsigned long flags;
925 	int ret;
926 
927 	spin_lock_irqsave(&info->slock, flags);
928 	ret = kfifo_put(&info->port.xmit_fifo, ch);
929 	spin_unlock_irqrestore(&info->slock, flags);
930 
931 	return ret;
932 }
933 
934 
935 static void mxser_flush_chars(struct tty_struct *tty)
936 {
937 	struct mxser_port *info = tty->driver_data;
938 
939 	if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped ||
940 			(tty->hw_stopped && !mxser_16550A_or_MUST(info)))
941 		return;
942 
943 	mxser_start_tx(info);
944 }
945 
946 static unsigned int mxser_write_room(struct tty_struct *tty)
947 {
948 	struct mxser_port *info = tty->driver_data;
949 
950 	return kfifo_avail(&info->port.xmit_fifo);
951 }
952 
953 static unsigned int mxser_chars_in_buffer(struct tty_struct *tty)
954 {
955 	struct mxser_port *info = tty->driver_data;
956 
957 	return kfifo_len(&info->port.xmit_fifo);
958 }
959 
960 /*
961  * ------------------------------------------------------------
962  * friends of mxser_ioctl()
963  * ------------------------------------------------------------
964  */
965 static int mxser_get_serial_info(struct tty_struct *tty,
966 		struct serial_struct *ss)
967 {
968 	struct mxser_port *info = tty->driver_data;
969 	struct tty_port *port = &info->port;
970 	unsigned int closing_wait, close_delay;
971 
972 	mutex_lock(&port->mutex);
973 
974 	close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
975 	closing_wait = info->port.closing_wait;
976 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
977 		closing_wait = jiffies_to_msecs(closing_wait) / 10;
978 
979 	ss->type = info->type;
980 	ss->line = tty->index;
981 	ss->port = info->ioaddr;
982 	ss->irq = info->board->irq;
983 	ss->flags = info->port.flags;
984 	ss->baud_base = MXSER_BAUD_BASE;
985 	ss->close_delay = close_delay;
986 	ss->closing_wait = closing_wait;
987 	ss->custom_divisor = MXSER_CUSTOM_DIVISOR,
988 	mutex_unlock(&port->mutex);
989 	return 0;
990 }
991 
992 static int mxser_set_serial_info(struct tty_struct *tty,
993 		struct serial_struct *ss)
994 {
995 	struct mxser_port *info = tty->driver_data;
996 	struct tty_port *port = &info->port;
997 	speed_t baud;
998 	unsigned long sl_flags;
999 	unsigned int old_speed, close_delay, closing_wait;
1000 	int retval = 0;
1001 
1002 	if (tty_io_error(tty))
1003 		return -EIO;
1004 
1005 	mutex_lock(&port->mutex);
1006 
1007 	if (ss->irq != info->board->irq ||
1008 			ss->port != info->ioaddr) {
1009 		mutex_unlock(&port->mutex);
1010 		return -EINVAL;
1011 	}
1012 
1013 	old_speed = port->flags & ASYNC_SPD_MASK;
1014 
1015 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
1016 	closing_wait = ss->closing_wait;
1017 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
1018 		closing_wait = msecs_to_jiffies(closing_wait * 10);
1019 
1020 	if (!capable(CAP_SYS_ADMIN)) {
1021 		if ((ss->baud_base != MXSER_BAUD_BASE) ||
1022 				(close_delay != port->close_delay) ||
1023 				(closing_wait != port->closing_wait) ||
1024 				((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) {
1025 			mutex_unlock(&port->mutex);
1026 			return -EPERM;
1027 		}
1028 		port->flags = (port->flags & ~ASYNC_USR_MASK) |
1029 				(ss->flags & ASYNC_USR_MASK);
1030 	} else {
1031 		/*
1032 		 * OK, past this point, all the error checking has been done.
1033 		 * At this point, we start making changes.....
1034 		 */
1035 		port->flags = ((port->flags & ~ASYNC_FLAGS) |
1036 				(ss->flags & ASYNC_FLAGS));
1037 		port->close_delay = close_delay;
1038 		port->closing_wait = closing_wait;
1039 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
1040 				(ss->baud_base != MXSER_BAUD_BASE ||
1041 				ss->custom_divisor !=
1042 				MXSER_CUSTOM_DIVISOR)) {
1043 			if (ss->custom_divisor == 0) {
1044 				mutex_unlock(&port->mutex);
1045 				return -EINVAL;
1046 			}
1047 			baud = ss->baud_base / ss->custom_divisor;
1048 			tty_encode_baud_rate(tty, baud, baud);
1049 		}
1050 
1051 		info->type = ss->type;
1052 
1053 		mxser_process_txrx_fifo(info);
1054 	}
1055 
1056 	if (tty_port_initialized(port)) {
1057 		if (old_speed != (port->flags & ASYNC_SPD_MASK)) {
1058 			spin_lock_irqsave(&info->slock, sl_flags);
1059 			mxser_change_speed(tty, NULL);
1060 			spin_unlock_irqrestore(&info->slock, sl_flags);
1061 		}
1062 	} else {
1063 		retval = mxser_activate(port, tty);
1064 		if (retval == 0)
1065 			tty_port_set_initialized(port, 1);
1066 	}
1067 	mutex_unlock(&port->mutex);
1068 	return retval;
1069 }
1070 
1071 /*
1072  * mxser_get_lsr_info - get line status register info
1073  *
1074  * Purpose: Let user call ioctl() to get info when the UART physically
1075  *	    is emptied.  On bus types like RS485, the transmitter must
1076  *	    release the bus after transmitting. This must be done when
1077  *	    the transmit shift register is empty, not be done when the
1078  *	    transmit holding register is empty.  This functionality
1079  *	    allows an RS485 driver to be written in user space.
1080  */
1081 static int mxser_get_lsr_info(struct mxser_port *info,
1082 		unsigned int __user *value)
1083 {
1084 	unsigned char status;
1085 	unsigned int result;
1086 	unsigned long flags;
1087 
1088 	spin_lock_irqsave(&info->slock, flags);
1089 	status = inb(info->ioaddr + UART_LSR);
1090 	spin_unlock_irqrestore(&info->slock, flags);
1091 	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1092 	return put_user(result, value);
1093 }
1094 
1095 static int mxser_tiocmget(struct tty_struct *tty)
1096 {
1097 	struct mxser_port *info = tty->driver_data;
1098 	unsigned char control;
1099 	unsigned long flags;
1100 	u8 msr;
1101 
1102 	if (tty_io_error(tty))
1103 		return -EIO;
1104 
1105 	spin_lock_irqsave(&info->slock, flags);
1106 	control = info->MCR;
1107 	msr = mxser_check_modem_status(tty, info);
1108 	spin_unlock_irqrestore(&info->slock, flags);
1109 
1110 	return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
1111 		    ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
1112 		    ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |
1113 		    ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) |
1114 		    ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) |
1115 		    ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0);
1116 }
1117 
1118 static int mxser_tiocmset(struct tty_struct *tty,
1119 		unsigned int set, unsigned int clear)
1120 {
1121 	struct mxser_port *info = tty->driver_data;
1122 	unsigned long flags;
1123 
1124 	if (tty_io_error(tty))
1125 		return -EIO;
1126 
1127 	spin_lock_irqsave(&info->slock, flags);
1128 
1129 	if (set & TIOCM_RTS)
1130 		info->MCR |= UART_MCR_RTS;
1131 	if (set & TIOCM_DTR)
1132 		info->MCR |= UART_MCR_DTR;
1133 
1134 	if (clear & TIOCM_RTS)
1135 		info->MCR &= ~UART_MCR_RTS;
1136 	if (clear & TIOCM_DTR)
1137 		info->MCR &= ~UART_MCR_DTR;
1138 
1139 	outb(info->MCR, info->ioaddr + UART_MCR);
1140 	spin_unlock_irqrestore(&info->slock, flags);
1141 	return 0;
1142 }
1143 
1144 static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg,
1145 		struct async_icount *cprev)
1146 {
1147 	struct async_icount cnow;
1148 	unsigned long flags;
1149 	int ret;
1150 
1151 	spin_lock_irqsave(&info->slock, flags);
1152 	cnow = info->icount;	/* atomic copy */
1153 	spin_unlock_irqrestore(&info->slock, flags);
1154 
1155 	ret =	((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
1156 		((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
1157 		((arg & TIOCM_CD)  && (cnow.dcd != cprev->dcd)) ||
1158 		((arg & TIOCM_CTS) && (cnow.cts != cprev->cts));
1159 
1160 	*cprev = cnow;
1161 
1162 	return ret;
1163 }
1164 
1165 /* We should likely switch to TIOCGRS485/TIOCSRS485. */
1166 static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set,
1167 		int __user *u_opmode)
1168 {
1169 	int opmode, p = index % 4;
1170 	int shiftbit = p * 2;
1171 	u8 val;
1172 
1173 	if (port->board->must_hwid != MOXA_MUST_MU860_HWID)
1174 		return -EFAULT;
1175 
1176 	if (set) {
1177 		if (get_user(opmode, u_opmode))
1178 			return -EFAULT;
1179 
1180 		if (opmode & ~OP_MODE_MASK)
1181 			return -EINVAL;
1182 
1183 		spin_lock_irq(&port->slock);
1184 		val = inb(port->opmode_ioaddr);
1185 		val &= ~(OP_MODE_MASK << shiftbit);
1186 		val |= (opmode << shiftbit);
1187 		outb(val, port->opmode_ioaddr);
1188 		spin_unlock_irq(&port->slock);
1189 
1190 		return 0;
1191 	}
1192 
1193 	spin_lock_irq(&port->slock);
1194 	opmode = inb(port->opmode_ioaddr) >> shiftbit;
1195 	spin_unlock_irq(&port->slock);
1196 
1197 	return put_user(opmode & OP_MODE_MASK, u_opmode);
1198 }
1199 
1200 static int mxser_ioctl(struct tty_struct *tty,
1201 		unsigned int cmd, unsigned long arg)
1202 {
1203 	struct mxser_port *info = tty->driver_data;
1204 	struct async_icount cnow;
1205 	unsigned long flags;
1206 	void __user *argp = (void __user *)arg;
1207 
1208 	if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE)
1209 		return mxser_ioctl_op_mode(info, tty->index,
1210 				cmd == MOXA_SET_OP_MODE, argp);
1211 
1212 	if (cmd != TIOCMIWAIT && tty_io_error(tty))
1213 		return -EIO;
1214 
1215 	switch (cmd) {
1216 	case TIOCSERGETLSR:	/* Get line status register */
1217 		return  mxser_get_lsr_info(info, argp);
1218 		/*
1219 		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1220 		 * - mask passed in arg for lines of interest
1221 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1222 		 * Caller should use TIOCGICOUNT to see which one it was
1223 		 */
1224 	case TIOCMIWAIT:
1225 		spin_lock_irqsave(&info->slock, flags);
1226 		cnow = info->icount;	/* note the counters on entry */
1227 		spin_unlock_irqrestore(&info->slock, flags);
1228 
1229 		return wait_event_interruptible(info->port.delta_msr_wait,
1230 				mxser_cflags_changed(info, arg, &cnow));
1231 	default:
1232 		return -ENOIOCTLCMD;
1233 	}
1234 	return 0;
1235 }
1236 
1237 	/*
1238 	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1239 	 * Return: write counters to the user passed counter struct
1240 	 * NB: both 1->0 and 0->1 transitions are counted except for
1241 	 *     RI where only 0->1 is counted.
1242 	 */
1243 
1244 static int mxser_get_icount(struct tty_struct *tty,
1245 		struct serial_icounter_struct *icount)
1246 
1247 {
1248 	struct mxser_port *info = tty->driver_data;
1249 	struct async_icount cnow;
1250 	unsigned long flags;
1251 
1252 	spin_lock_irqsave(&info->slock, flags);
1253 	cnow = info->icount;
1254 	spin_unlock_irqrestore(&info->slock, flags);
1255 
1256 	icount->frame = cnow.frame;
1257 	icount->brk = cnow.brk;
1258 	icount->overrun = cnow.overrun;
1259 	icount->buf_overrun = cnow.buf_overrun;
1260 	icount->parity = cnow.parity;
1261 	icount->rx = cnow.rx;
1262 	icount->tx = cnow.tx;
1263 	icount->cts = cnow.cts;
1264 	icount->dsr = cnow.dsr;
1265 	icount->rng = cnow.rng;
1266 	icount->dcd = cnow.dcd;
1267 	return 0;
1268 }
1269 
1270 /*
1271  * This routine is called by the upper-layer tty layer to signal that
1272  * incoming characters should be throttled.
1273  */
1274 static void mxser_throttle(struct tty_struct *tty)
1275 {
1276 	struct mxser_port *info = tty->driver_data;
1277 
1278 	if (I_IXOFF(tty)) {
1279 		if (info->board->must_hwid) {
1280 			info->IER &= ~MOXA_MUST_RECV_ISR;
1281 			outb(info->IER, info->ioaddr + UART_IER);
1282 		} else {
1283 			info->x_char = STOP_CHAR(tty);
1284 			outb(0, info->ioaddr + UART_IER);
1285 			info->IER |= UART_IER_THRI;
1286 			outb(info->IER, info->ioaddr + UART_IER);
1287 		}
1288 	}
1289 
1290 	if (C_CRTSCTS(tty)) {
1291 		info->MCR &= ~UART_MCR_RTS;
1292 		outb(info->MCR, info->ioaddr + UART_MCR);
1293 	}
1294 }
1295 
1296 static void mxser_unthrottle(struct tty_struct *tty)
1297 {
1298 	struct mxser_port *info = tty->driver_data;
1299 
1300 	/* startrx */
1301 	if (I_IXOFF(tty)) {
1302 		if (info->x_char)
1303 			info->x_char = 0;
1304 		else {
1305 			if (info->board->must_hwid) {
1306 				info->IER |= MOXA_MUST_RECV_ISR;
1307 				outb(info->IER, info->ioaddr + UART_IER);
1308 			} else {
1309 				info->x_char = START_CHAR(tty);
1310 				outb(0, info->ioaddr + UART_IER);
1311 				info->IER |= UART_IER_THRI;
1312 				outb(info->IER, info->ioaddr + UART_IER);
1313 			}
1314 		}
1315 	}
1316 
1317 	if (C_CRTSCTS(tty)) {
1318 		info->MCR |= UART_MCR_RTS;
1319 		outb(info->MCR, info->ioaddr + UART_MCR);
1320 	}
1321 }
1322 
1323 /*
1324  * mxser_stop() and mxser_start()
1325  *
1326  * This routines are called before setting or resetting tty->flow.stopped.
1327  * They enable or disable transmitter interrupts, as necessary.
1328  */
1329 static void mxser_stop(struct tty_struct *tty)
1330 {
1331 	struct mxser_port *info = tty->driver_data;
1332 	unsigned long flags;
1333 
1334 	spin_lock_irqsave(&info->slock, flags);
1335 	if (info->IER & UART_IER_THRI)
1336 		__mxser_stop_tx(info);
1337 	spin_unlock_irqrestore(&info->slock, flags);
1338 }
1339 
1340 static void mxser_start(struct tty_struct *tty)
1341 {
1342 	struct mxser_port *info = tty->driver_data;
1343 	unsigned long flags;
1344 
1345 	spin_lock_irqsave(&info->slock, flags);
1346 	if (!kfifo_is_empty(&info->port.xmit_fifo))
1347 		__mxser_start_tx(info);
1348 	spin_unlock_irqrestore(&info->slock, flags);
1349 }
1350 
1351 static void mxser_set_termios(struct tty_struct *tty, 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 = 0;
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 			char 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 		unsigned char 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 		info->port.close_delay = 5 * HZ / 10;
1774 		info->port.closing_wait = 30 * HZ;
1775 		spin_lock_init(&info->slock);
1776 
1777 		/* before set INT ISR, disable all int */
1778 		outb(inb(info->ioaddr + UART_IER) & 0xf0,
1779 			info->ioaddr + UART_IER);
1780 	}
1781 }
1782 
1783 static int mxser_probe(struct pci_dev *pdev,
1784 		const struct pci_device_id *ent)
1785 {
1786 	struct mxser_board *brd;
1787 	unsigned int i, base;
1788 	unsigned long ioaddress;
1789 	unsigned short nports = MXSER_NPORTS(ent->driver_data);
1790 	struct device *tty_dev;
1791 	int retval = -EINVAL;
1792 
1793 	i = find_first_zero_bit(mxser_boards, MXSER_BOARDS);
1794 	if (i >= MXSER_BOARDS) {
1795 		dev_err(&pdev->dev, "too many boards found (maximum %d), board "
1796 				"not configured\n", MXSER_BOARDS);
1797 		goto err;
1798 	}
1799 
1800 	brd = devm_kzalloc(&pdev->dev, struct_size(brd, ports, nports),
1801 			GFP_KERNEL);
1802 	if (!brd)
1803 		goto err;
1804 
1805 	brd->idx = i;
1806 	__set_bit(brd->idx, mxser_boards);
1807 	base = i * MXSER_PORTS_PER_BOARD;
1808 
1809 	retval = pcim_enable_device(pdev);
1810 	if (retval) {
1811 		dev_err(&pdev->dev, "PCI enable failed\n");
1812 		goto err_zero;
1813 	}
1814 
1815 	/* io address */
1816 	ioaddress = pci_resource_start(pdev, 2);
1817 	retval = pci_request_region(pdev, 2, "mxser(IO)");
1818 	if (retval)
1819 		goto err_zero;
1820 
1821 	brd->nports = nports;
1822 	for (i = 0; i < nports; i++)
1823 		brd->ports[i].ioaddr = ioaddress + 8 * i;
1824 
1825 	/* vector */
1826 	ioaddress = pci_resource_start(pdev, 3);
1827 	retval = pci_request_region(pdev, 3, "mxser(vector)");
1828 	if (retval)
1829 		goto err_zero;
1830 	brd->vector = ioaddress;
1831 
1832 	/* irq */
1833 	brd->irq = pdev->irq;
1834 
1835 	mxser_initbrd(brd, ent->driver_data & MXSER_HIGHBAUD);
1836 
1837 	retval = devm_request_irq(&pdev->dev, brd->irq, mxser_interrupt,
1838 			IRQF_SHARED, "mxser", brd);
1839 	if (retval) {
1840 		dev_err(&pdev->dev, "request irq failed");
1841 		goto err_relbrd;
1842 	}
1843 
1844 	for (i = 0; i < nports; i++) {
1845 		tty_dev = tty_port_register_device(&brd->ports[i].port,
1846 				mxvar_sdriver, base + i, &pdev->dev);
1847 		if (IS_ERR(tty_dev)) {
1848 			retval = PTR_ERR(tty_dev);
1849 			for (; i > 0; i--)
1850 				tty_unregister_device(mxvar_sdriver,
1851 					base + i - 1);
1852 			goto err_relbrd;
1853 		}
1854 	}
1855 
1856 	pci_set_drvdata(pdev, brd);
1857 
1858 	return 0;
1859 err_relbrd:
1860 	for (i = 0; i < nports; i++)
1861 		tty_port_destroy(&brd->ports[i].port);
1862 err_zero:
1863 	__clear_bit(brd->idx, mxser_boards);
1864 err:
1865 	return retval;
1866 }
1867 
1868 static void mxser_remove(struct pci_dev *pdev)
1869 {
1870 	struct mxser_board *brd = pci_get_drvdata(pdev);
1871 	unsigned int i, base = brd->idx * MXSER_PORTS_PER_BOARD;
1872 
1873 	for (i = 0; i < brd->nports; i++) {
1874 		tty_unregister_device(mxvar_sdriver, base + i);
1875 		tty_port_destroy(&brd->ports[i].port);
1876 	}
1877 
1878 	__clear_bit(brd->idx, mxser_boards);
1879 }
1880 
1881 static struct pci_driver mxser_driver = {
1882 	.name = "mxser",
1883 	.id_table = mxser_pcibrds,
1884 	.probe = mxser_probe,
1885 	.remove = mxser_remove
1886 };
1887 
1888 static int __init mxser_module_init(void)
1889 {
1890 	int retval;
1891 
1892 	mxvar_sdriver = tty_alloc_driver(MXSER_PORTS, TTY_DRIVER_REAL_RAW |
1893 			TTY_DRIVER_DYNAMIC_DEV);
1894 	if (IS_ERR(mxvar_sdriver))
1895 		return PTR_ERR(mxvar_sdriver);
1896 
1897 	/* Initialize the tty_driver structure */
1898 	mxvar_sdriver->name = "ttyMI";
1899 	mxvar_sdriver->major = ttymajor;
1900 	mxvar_sdriver->minor_start = 0;
1901 	mxvar_sdriver->type = TTY_DRIVER_TYPE_SERIAL;
1902 	mxvar_sdriver->subtype = SERIAL_TYPE_NORMAL;
1903 	mxvar_sdriver->init_termios = tty_std_termios;
1904 	mxvar_sdriver->init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
1905 	tty_set_operations(mxvar_sdriver, &mxser_ops);
1906 
1907 	retval = tty_register_driver(mxvar_sdriver);
1908 	if (retval) {
1909 		printk(KERN_ERR "Couldn't install MOXA Smartio/Industio family "
1910 				"tty driver !\n");
1911 		goto err_put;
1912 	}
1913 
1914 	retval = pci_register_driver(&mxser_driver);
1915 	if (retval) {
1916 		printk(KERN_ERR "mxser: can't register pci driver\n");
1917 		goto err_unr;
1918 	}
1919 
1920 	return 0;
1921 err_unr:
1922 	tty_unregister_driver(mxvar_sdriver);
1923 err_put:
1924 	tty_driver_kref_put(mxvar_sdriver);
1925 	return retval;
1926 }
1927 
1928 static void __exit mxser_module_exit(void)
1929 {
1930 	pci_unregister_driver(&mxser_driver);
1931 	tty_unregister_driver(mxvar_sdriver);
1932 	tty_driver_kref_put(mxvar_sdriver);
1933 }
1934 
1935 module_init(mxser_module_init);
1936 module_exit(mxser_module_exit);
1937