xref: /linux/drivers/usb/serial/f81232.c (revision 44f57d78)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Fintek F81232 USB to serial adaptor driver
4  *
5  * Copyright (C) 2012 Greg Kroah-Hartman (gregkh@linuxfoundation.org)
6  * Copyright (C) 2012 Linux Foundation
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/errno.h>
11 #include <linux/slab.h>
12 #include <linux/tty.h>
13 #include <linux/tty_driver.h>
14 #include <linux/tty_flip.h>
15 #include <linux/serial.h>
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/mutex.h>
19 #include <linux/uaccess.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/serial_reg.h>
23 
24 static const struct usb_device_id id_table[] = {
25 	{ USB_DEVICE(0x1934, 0x0706) },
26 	{ }					/* Terminating entry */
27 };
28 MODULE_DEVICE_TABLE(usb, id_table);
29 
30 /* Maximum baudrate for F81232 */
31 #define F81232_MAX_BAUDRATE		1500000
32 #define F81232_DEF_BAUDRATE		9600
33 
34 /* USB Control EP parameter */
35 #define F81232_REGISTER_REQUEST		0xa0
36 #define F81232_GET_REGISTER		0xc0
37 #define F81232_SET_REGISTER		0x40
38 
39 #define SERIAL_BASE_ADDRESS		0x0120
40 #define RECEIVE_BUFFER_REGISTER		(0x00 + SERIAL_BASE_ADDRESS)
41 #define INTERRUPT_ENABLE_REGISTER	(0x01 + SERIAL_BASE_ADDRESS)
42 #define FIFO_CONTROL_REGISTER		(0x02 + SERIAL_BASE_ADDRESS)
43 #define LINE_CONTROL_REGISTER		(0x03 + SERIAL_BASE_ADDRESS)
44 #define MODEM_CONTROL_REGISTER		(0x04 + SERIAL_BASE_ADDRESS)
45 #define LINE_STATUS_REGISTER		(0x05 + SERIAL_BASE_ADDRESS)
46 #define MODEM_STATUS_REGISTER		(0x06 + SERIAL_BASE_ADDRESS)
47 
48 /*
49  * F81232 Clock registers (106h)
50  *
51  * Bit1-0:	Clock source selector
52  *			00: 1.846MHz.
53  *			01: 18.46MHz.
54  *			10: 24MHz.
55  *			11: 14.77MHz.
56  */
57 #define F81232_CLK_REGISTER		0x106
58 #define F81232_CLK_1_846_MHZ		0
59 #define F81232_CLK_18_46_MHZ		BIT(0)
60 #define F81232_CLK_24_MHZ		BIT(1)
61 #define F81232_CLK_14_77_MHZ		(BIT(1) | BIT(0))
62 #define F81232_CLK_MASK			GENMASK(1, 0)
63 
64 struct f81232_private {
65 	struct mutex lock;
66 	u8 modem_control;
67 	u8 modem_status;
68 	u8 shadow_lcr;
69 	speed_t baud_base;
70 	struct work_struct lsr_work;
71 	struct work_struct interrupt_work;
72 	struct usb_serial_port *port;
73 };
74 
75 static u32 const baudrate_table[] = { 115200, 921600, 1152000, 1500000 };
76 static u8 const clock_table[] = { F81232_CLK_1_846_MHZ, F81232_CLK_14_77_MHZ,
77 				F81232_CLK_18_46_MHZ, F81232_CLK_24_MHZ };
78 
79 static int calc_baud_divisor(speed_t baudrate, speed_t clockrate)
80 {
81 	if (!baudrate)
82 		return 0;
83 
84 	return DIV_ROUND_CLOSEST(clockrate, baudrate);
85 }
86 
87 static int f81232_get_register(struct usb_serial_port *port, u16 reg, u8 *val)
88 {
89 	int status;
90 	u8 *tmp;
91 	struct usb_device *dev = port->serial->dev;
92 
93 	tmp = kmalloc(sizeof(*val), GFP_KERNEL);
94 	if (!tmp)
95 		return -ENOMEM;
96 
97 	status = usb_control_msg(dev,
98 				usb_rcvctrlpipe(dev, 0),
99 				F81232_REGISTER_REQUEST,
100 				F81232_GET_REGISTER,
101 				reg,
102 				0,
103 				tmp,
104 				sizeof(*val),
105 				USB_CTRL_GET_TIMEOUT);
106 	if (status != sizeof(*val)) {
107 		dev_err(&port->dev, "%s failed status: %d\n", __func__, status);
108 
109 		if (status < 0)
110 			status = usb_translate_errors(status);
111 		else
112 			status = -EIO;
113 	} else {
114 		status = 0;
115 		*val = *tmp;
116 	}
117 
118 	kfree(tmp);
119 	return status;
120 }
121 
122 static int f81232_set_register(struct usb_serial_port *port, u16 reg, u8 val)
123 {
124 	int status;
125 	u8 *tmp;
126 	struct usb_device *dev = port->serial->dev;
127 
128 	tmp = kmalloc(sizeof(val), GFP_KERNEL);
129 	if (!tmp)
130 		return -ENOMEM;
131 
132 	*tmp = val;
133 
134 	status = usb_control_msg(dev,
135 				usb_sndctrlpipe(dev, 0),
136 				F81232_REGISTER_REQUEST,
137 				F81232_SET_REGISTER,
138 				reg,
139 				0,
140 				tmp,
141 				sizeof(val),
142 				USB_CTRL_SET_TIMEOUT);
143 	if (status != sizeof(val)) {
144 		dev_err(&port->dev, "%s failed status: %d\n", __func__, status);
145 
146 		if (status < 0)
147 			status = usb_translate_errors(status);
148 		else
149 			status = -EIO;
150 	} else {
151 		status = 0;
152 	}
153 
154 	kfree(tmp);
155 	return status;
156 }
157 
158 static int f81232_set_mask_register(struct usb_serial_port *port, u16 reg,
159 					u8 mask, u8 val)
160 {
161 	int status;
162 	u8 tmp;
163 
164 	status = f81232_get_register(port, reg, &tmp);
165 	if (status)
166 		return status;
167 
168 	tmp = (tmp & ~mask) | (val & mask);
169 
170 	return f81232_set_register(port, reg, tmp);
171 }
172 
173 static void f81232_read_msr(struct usb_serial_port *port)
174 {
175 	int status;
176 	u8 current_msr;
177 	struct tty_struct *tty;
178 	struct f81232_private *priv = usb_get_serial_port_data(port);
179 
180 	mutex_lock(&priv->lock);
181 	status = f81232_get_register(port, MODEM_STATUS_REGISTER,
182 			&current_msr);
183 	if (status) {
184 		dev_err(&port->dev, "%s fail, status: %d\n", __func__, status);
185 		mutex_unlock(&priv->lock);
186 		return;
187 	}
188 
189 	if (!(current_msr & UART_MSR_ANY_DELTA)) {
190 		mutex_unlock(&priv->lock);
191 		return;
192 	}
193 
194 	priv->modem_status = current_msr;
195 
196 	if (current_msr & UART_MSR_DCTS)
197 		port->icount.cts++;
198 	if (current_msr & UART_MSR_DDSR)
199 		port->icount.dsr++;
200 	if (current_msr & UART_MSR_TERI)
201 		port->icount.rng++;
202 	if (current_msr & UART_MSR_DDCD) {
203 		port->icount.dcd++;
204 		tty = tty_port_tty_get(&port->port);
205 		if (tty) {
206 			usb_serial_handle_dcd_change(port, tty,
207 					current_msr & UART_MSR_DCD);
208 
209 			tty_kref_put(tty);
210 		}
211 	}
212 
213 	wake_up_interruptible(&port->port.delta_msr_wait);
214 	mutex_unlock(&priv->lock);
215 }
216 
217 static int f81232_set_mctrl(struct usb_serial_port *port,
218 					   unsigned int set, unsigned int clear)
219 {
220 	u8 val;
221 	int status;
222 	struct f81232_private *priv = usb_get_serial_port_data(port);
223 
224 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
225 		return 0;	/* no change */
226 
227 	/* 'set' takes precedence over 'clear' */
228 	clear &= ~set;
229 
230 	/* force enable interrupt with OUT2 */
231 	mutex_lock(&priv->lock);
232 	val = UART_MCR_OUT2 | priv->modem_control;
233 
234 	if (clear & TIOCM_DTR)
235 		val &= ~UART_MCR_DTR;
236 
237 	if (clear & TIOCM_RTS)
238 		val &= ~UART_MCR_RTS;
239 
240 	if (set & TIOCM_DTR)
241 		val |= UART_MCR_DTR;
242 
243 	if (set & TIOCM_RTS)
244 		val |= UART_MCR_RTS;
245 
246 	dev_dbg(&port->dev, "%s new:%02x old:%02x\n", __func__,
247 			val, priv->modem_control);
248 
249 	status = f81232_set_register(port, MODEM_CONTROL_REGISTER, val);
250 	if (status) {
251 		dev_err(&port->dev, "%s set MCR status < 0\n", __func__);
252 		mutex_unlock(&priv->lock);
253 		return status;
254 	}
255 
256 	priv->modem_control = val;
257 	mutex_unlock(&priv->lock);
258 
259 	return 0;
260 }
261 
262 static void f81232_update_line_status(struct usb_serial_port *port,
263 				      unsigned char *data,
264 				      size_t actual_length)
265 {
266 	struct f81232_private *priv = usb_get_serial_port_data(port);
267 
268 	if (!actual_length)
269 		return;
270 
271 	switch (data[0] & 0x07) {
272 	case 0x00: /* msr change */
273 		dev_dbg(&port->dev, "IIR: MSR Change: %02x\n", data[0]);
274 		schedule_work(&priv->interrupt_work);
275 		break;
276 	case 0x02: /* tx-empty */
277 		break;
278 	case 0x04: /* rx data available */
279 		break;
280 	case 0x06: /* lsr change */
281 		/* we can forget it. the LSR will read from bulk-in */
282 		dev_dbg(&port->dev, "IIR: LSR Change: %02x\n", data[0]);
283 		break;
284 	}
285 }
286 
287 static void f81232_read_int_callback(struct urb *urb)
288 {
289 	struct usb_serial_port *port =  urb->context;
290 	unsigned char *data = urb->transfer_buffer;
291 	unsigned int actual_length = urb->actual_length;
292 	int status = urb->status;
293 	int retval;
294 
295 	switch (status) {
296 	case 0:
297 		/* success */
298 		break;
299 	case -ECONNRESET:
300 	case -ENOENT:
301 	case -ESHUTDOWN:
302 		/* this urb is terminated, clean up */
303 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
304 			__func__, status);
305 		return;
306 	default:
307 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
308 			__func__, status);
309 		goto exit;
310 	}
311 
312 	usb_serial_debug_data(&port->dev, __func__,
313 			      urb->actual_length, urb->transfer_buffer);
314 
315 	f81232_update_line_status(port, data, actual_length);
316 
317 exit:
318 	retval = usb_submit_urb(urb, GFP_ATOMIC);
319 	if (retval)
320 		dev_err(&urb->dev->dev,
321 			"%s - usb_submit_urb failed with result %d\n",
322 			__func__, retval);
323 }
324 
325 static void f81232_process_read_urb(struct urb *urb)
326 {
327 	struct usb_serial_port *port = urb->context;
328 	struct f81232_private *priv = usb_get_serial_port_data(port);
329 	unsigned char *data = urb->transfer_buffer;
330 	char tty_flag;
331 	unsigned int i;
332 	u8 lsr;
333 
334 	/*
335 	 * When opening the port we get a 1-byte packet with the current LSR,
336 	 * which we discard.
337 	 */
338 	if ((urb->actual_length < 2) || (urb->actual_length % 2))
339 		return;
340 
341 	/* bulk-in data: [LSR(1Byte)+DATA(1Byte)][LSR(1Byte)+DATA(1Byte)]... */
342 
343 	for (i = 0; i < urb->actual_length; i += 2) {
344 		tty_flag = TTY_NORMAL;
345 		lsr = data[i];
346 
347 		if (lsr & UART_LSR_BRK_ERROR_BITS) {
348 			if (lsr & UART_LSR_BI) {
349 				tty_flag = TTY_BREAK;
350 				port->icount.brk++;
351 				usb_serial_handle_break(port);
352 			} else if (lsr & UART_LSR_PE) {
353 				tty_flag = TTY_PARITY;
354 				port->icount.parity++;
355 			} else if (lsr & UART_LSR_FE) {
356 				tty_flag = TTY_FRAME;
357 				port->icount.frame++;
358 			}
359 
360 			if (lsr & UART_LSR_OE) {
361 				port->icount.overrun++;
362 				schedule_work(&priv->lsr_work);
363 				tty_insert_flip_char(&port->port, 0,
364 						TTY_OVERRUN);
365 			}
366 		}
367 
368 		if (port->port.console && port->sysrq) {
369 			if (usb_serial_handle_sysrq_char(port, data[i + 1]))
370 				continue;
371 		}
372 
373 		tty_insert_flip_char(&port->port, data[i + 1], tty_flag);
374 	}
375 
376 	tty_flip_buffer_push(&port->port);
377 }
378 
379 static void f81232_break_ctl(struct tty_struct *tty, int break_state)
380 {
381 	struct usb_serial_port *port = tty->driver_data;
382 	struct f81232_private *priv = usb_get_serial_port_data(port);
383 	int status;
384 
385 	mutex_lock(&priv->lock);
386 
387 	if (break_state)
388 		priv->shadow_lcr |= UART_LCR_SBC;
389 	else
390 		priv->shadow_lcr &= ~UART_LCR_SBC;
391 
392 	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
393 					priv->shadow_lcr);
394 	if (status)
395 		dev_err(&port->dev, "set break failed: %d\n", status);
396 
397 	mutex_unlock(&priv->lock);
398 }
399 
400 static int f81232_find_clk(speed_t baudrate)
401 {
402 	int idx;
403 
404 	for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) {
405 		if (baudrate <= baudrate_table[idx] &&
406 				baudrate_table[idx] % baudrate == 0)
407 			return idx;
408 	}
409 
410 	return -EINVAL;
411 }
412 
413 static void f81232_set_baudrate(struct tty_struct *tty,
414 				struct usb_serial_port *port, speed_t baudrate,
415 				speed_t old_baudrate)
416 {
417 	struct f81232_private *priv = usb_get_serial_port_data(port);
418 	u8 lcr;
419 	int divisor;
420 	int status = 0;
421 	int i;
422 	int idx;
423 	speed_t baud_list[] = { baudrate, old_baudrate, F81232_DEF_BAUDRATE };
424 
425 	for (i = 0; i < ARRAY_SIZE(baud_list); ++i) {
426 		idx = f81232_find_clk(baud_list[i]);
427 		if (idx >= 0) {
428 			baudrate = baud_list[i];
429 			tty_encode_baud_rate(tty, baudrate, baudrate);
430 			break;
431 		}
432 	}
433 
434 	if (idx < 0)
435 		return;
436 
437 	priv->baud_base = baudrate_table[idx];
438 	divisor = calc_baud_divisor(baudrate, priv->baud_base);
439 
440 	status = f81232_set_mask_register(port, F81232_CLK_REGISTER,
441 			F81232_CLK_MASK, clock_table[idx]);
442 	if (status) {
443 		dev_err(&port->dev, "%s failed to set CLK_REG: %d\n",
444 			__func__, status);
445 		return;
446 	}
447 
448 	status = f81232_get_register(port, LINE_CONTROL_REGISTER,
449 			 &lcr); /* get LCR */
450 	if (status) {
451 		dev_err(&port->dev, "%s failed to get LCR: %d\n",
452 			__func__, status);
453 		return;
454 	}
455 
456 	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
457 			 lcr | UART_LCR_DLAB); /* Enable DLAB */
458 	if (status) {
459 		dev_err(&port->dev, "%s failed to set DLAB: %d\n",
460 			__func__, status);
461 		return;
462 	}
463 
464 	status = f81232_set_register(port, RECEIVE_BUFFER_REGISTER,
465 			 divisor & 0x00ff); /* low */
466 	if (status) {
467 		dev_err(&port->dev, "%s failed to set baudrate MSB: %d\n",
468 			__func__, status);
469 		goto reapply_lcr;
470 	}
471 
472 	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,
473 			 (divisor & 0xff00) >> 8); /* high */
474 	if (status) {
475 		dev_err(&port->dev, "%s failed to set baudrate LSB: %d\n",
476 			__func__, status);
477 	}
478 
479 reapply_lcr:
480 	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
481 			lcr & ~UART_LCR_DLAB);
482 	if (status) {
483 		dev_err(&port->dev, "%s failed to set DLAB: %d\n",
484 			__func__, status);
485 	}
486 }
487 
488 static int f81232_port_enable(struct usb_serial_port *port)
489 {
490 	u8 val;
491 	int status;
492 
493 	/* fifo on, trigger8, clear TX/RX*/
494 	val = UART_FCR_TRIGGER_8 | UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR |
495 			UART_FCR_CLEAR_XMIT;
496 
497 	status = f81232_set_register(port, FIFO_CONTROL_REGISTER, val);
498 	if (status) {
499 		dev_err(&port->dev, "%s failed to set FCR: %d\n",
500 			__func__, status);
501 		return status;
502 	}
503 
504 	/* MSR Interrupt only, LSR will read from Bulk-in odd byte */
505 	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,
506 			UART_IER_MSI);
507 	if (status) {
508 		dev_err(&port->dev, "%s failed to set IER: %d\n",
509 			__func__, status);
510 		return status;
511 	}
512 
513 	return 0;
514 }
515 
516 static int f81232_port_disable(struct usb_serial_port *port)
517 {
518 	int status;
519 
520 	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER, 0);
521 	if (status) {
522 		dev_err(&port->dev, "%s failed to set IER: %d\n",
523 			__func__, status);
524 		return status;
525 	}
526 
527 	return 0;
528 }
529 
530 static void f81232_set_termios(struct tty_struct *tty,
531 		struct usb_serial_port *port, struct ktermios *old_termios)
532 {
533 	struct f81232_private *priv = usb_get_serial_port_data(port);
534 	u8 new_lcr = 0;
535 	int status = 0;
536 	speed_t baudrate;
537 	speed_t old_baud;
538 
539 	/* Don't change anything if nothing has changed */
540 	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
541 		return;
542 
543 	if (C_BAUD(tty) == B0)
544 		f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
545 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
546 		f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
547 
548 	baudrate = tty_get_baud_rate(tty);
549 	if (baudrate > 0) {
550 		if (old_termios)
551 			old_baud = tty_termios_baud_rate(old_termios);
552 		else
553 			old_baud = F81232_DEF_BAUDRATE;
554 
555 		f81232_set_baudrate(tty, port, baudrate, old_baud);
556 	}
557 
558 	if (C_PARENB(tty)) {
559 		new_lcr |= UART_LCR_PARITY;
560 
561 		if (!C_PARODD(tty))
562 			new_lcr |= UART_LCR_EPAR;
563 
564 		if (C_CMSPAR(tty))
565 			new_lcr |= UART_LCR_SPAR;
566 	}
567 
568 	if (C_CSTOPB(tty))
569 		new_lcr |= UART_LCR_STOP;
570 
571 	switch (C_CSIZE(tty)) {
572 	case CS5:
573 		new_lcr |= UART_LCR_WLEN5;
574 		break;
575 	case CS6:
576 		new_lcr |= UART_LCR_WLEN6;
577 		break;
578 	case CS7:
579 		new_lcr |= UART_LCR_WLEN7;
580 		break;
581 	default:
582 	case CS8:
583 		new_lcr |= UART_LCR_WLEN8;
584 		break;
585 	}
586 
587 	mutex_lock(&priv->lock);
588 
589 	new_lcr |= (priv->shadow_lcr & UART_LCR_SBC);
590 	status = f81232_set_register(port, LINE_CONTROL_REGISTER, new_lcr);
591 	if (status) {
592 		dev_err(&port->dev, "%s failed to set LCR: %d\n",
593 			__func__, status);
594 	}
595 
596 	priv->shadow_lcr = new_lcr;
597 
598 	mutex_unlock(&priv->lock);
599 }
600 
601 static int f81232_tiocmget(struct tty_struct *tty)
602 {
603 	int r;
604 	struct usb_serial_port *port = tty->driver_data;
605 	struct f81232_private *port_priv = usb_get_serial_port_data(port);
606 	u8 mcr, msr;
607 
608 	/* force get current MSR changed state */
609 	f81232_read_msr(port);
610 
611 	mutex_lock(&port_priv->lock);
612 	mcr = port_priv->modem_control;
613 	msr = port_priv->modem_status;
614 	mutex_unlock(&port_priv->lock);
615 
616 	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
617 		(mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
618 		(msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
619 		(msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
620 		(msr & UART_MSR_RI ? TIOCM_RI : 0) |
621 		(msr & UART_MSR_DSR ? TIOCM_DSR : 0);
622 
623 	return r;
624 }
625 
626 static int f81232_tiocmset(struct tty_struct *tty,
627 			unsigned int set, unsigned int clear)
628 {
629 	struct usb_serial_port *port = tty->driver_data;
630 
631 	return f81232_set_mctrl(port, set, clear);
632 }
633 
634 static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
635 {
636 	int result;
637 
638 	result = f81232_port_enable(port);
639 	if (result)
640 		return result;
641 
642 	/* Setup termios */
643 	if (tty)
644 		f81232_set_termios(tty, port, NULL);
645 
646 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
647 	if (result) {
648 		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
649 			" error %d\n", __func__, result);
650 		return result;
651 	}
652 
653 	result = usb_serial_generic_open(tty, port);
654 	if (result) {
655 		usb_kill_urb(port->interrupt_in_urb);
656 		return result;
657 	}
658 
659 	return 0;
660 }
661 
662 static void f81232_close(struct usb_serial_port *port)
663 {
664 	struct f81232_private *port_priv = usb_get_serial_port_data(port);
665 
666 	f81232_port_disable(port);
667 	usb_serial_generic_close(port);
668 	usb_kill_urb(port->interrupt_in_urb);
669 	flush_work(&port_priv->interrupt_work);
670 	flush_work(&port_priv->lsr_work);
671 }
672 
673 static void f81232_dtr_rts(struct usb_serial_port *port, int on)
674 {
675 	if (on)
676 		f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
677 	else
678 		f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
679 }
680 
681 static int f81232_carrier_raised(struct usb_serial_port *port)
682 {
683 	u8 msr;
684 	struct f81232_private *priv = usb_get_serial_port_data(port);
685 
686 	mutex_lock(&priv->lock);
687 	msr = priv->modem_status;
688 	mutex_unlock(&priv->lock);
689 
690 	if (msr & UART_MSR_DCD)
691 		return 1;
692 	return 0;
693 }
694 
695 static int f81232_get_serial_info(struct tty_struct *tty,
696 		struct serial_struct *ss)
697 {
698 	struct usb_serial_port *port = tty->driver_data;
699 	struct f81232_private *priv = usb_get_serial_port_data(port);
700 
701 	ss->type = PORT_16550A;
702 	ss->line = port->minor;
703 	ss->port = port->port_number;
704 	ss->baud_base = priv->baud_base;
705 	return 0;
706 }
707 
708 static void  f81232_interrupt_work(struct work_struct *work)
709 {
710 	struct f81232_private *priv =
711 		container_of(work, struct f81232_private, interrupt_work);
712 
713 	f81232_read_msr(priv->port);
714 }
715 
716 static void f81232_lsr_worker(struct work_struct *work)
717 {
718 	struct f81232_private *priv;
719 	struct usb_serial_port *port;
720 	int status;
721 	u8 tmp;
722 
723 	priv = container_of(work, struct f81232_private, lsr_work);
724 	port = priv->port;
725 
726 	status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
727 	if (status)
728 		dev_warn(&port->dev, "read LSR failed: %d\n", status);
729 }
730 
731 static int f81232_port_probe(struct usb_serial_port *port)
732 {
733 	struct f81232_private *priv;
734 
735 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
736 	if (!priv)
737 		return -ENOMEM;
738 
739 	mutex_init(&priv->lock);
740 	INIT_WORK(&priv->interrupt_work,  f81232_interrupt_work);
741 	INIT_WORK(&priv->lsr_work, f81232_lsr_worker);
742 
743 	usb_set_serial_port_data(port, priv);
744 
745 	port->port.drain_delay = 256;
746 	priv->port = port;
747 
748 	return 0;
749 }
750 
751 static int f81232_port_remove(struct usb_serial_port *port)
752 {
753 	struct f81232_private *priv;
754 
755 	priv = usb_get_serial_port_data(port);
756 	kfree(priv);
757 
758 	return 0;
759 }
760 
761 static int f81232_suspend(struct usb_serial *serial, pm_message_t message)
762 {
763 	struct usb_serial_port *port = serial->port[0];
764 	struct f81232_private *port_priv = usb_get_serial_port_data(port);
765 	int i;
766 
767 	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
768 		usb_kill_urb(port->read_urbs[i]);
769 
770 	usb_kill_urb(port->interrupt_in_urb);
771 
772 	if (port_priv) {
773 		flush_work(&port_priv->interrupt_work);
774 		flush_work(&port_priv->lsr_work);
775 	}
776 
777 	return 0;
778 }
779 
780 static int f81232_resume(struct usb_serial *serial)
781 {
782 	struct usb_serial_port *port = serial->port[0];
783 	int result;
784 
785 	if (tty_port_initialized(&port->port)) {
786 		result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
787 		if (result) {
788 			dev_err(&port->dev, "submit interrupt urb failed: %d\n",
789 					result);
790 			return result;
791 		}
792 	}
793 
794 	return usb_serial_generic_resume(serial);
795 }
796 
797 static struct usb_serial_driver f81232_device = {
798 	.driver = {
799 		.owner =	THIS_MODULE,
800 		.name =		"f81232",
801 	},
802 	.id_table =		id_table,
803 	.num_ports =		1,
804 	.bulk_in_size =		256,
805 	.bulk_out_size =	256,
806 	.open =			f81232_open,
807 	.close =		f81232_close,
808 	.dtr_rts =		f81232_dtr_rts,
809 	.carrier_raised =	f81232_carrier_raised,
810 	.get_serial =		f81232_get_serial_info,
811 	.break_ctl =		f81232_break_ctl,
812 	.set_termios =		f81232_set_termios,
813 	.tiocmget =		f81232_tiocmget,
814 	.tiocmset =		f81232_tiocmset,
815 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
816 	.process_read_urb =	f81232_process_read_urb,
817 	.read_int_callback =	f81232_read_int_callback,
818 	.port_probe =		f81232_port_probe,
819 	.port_remove =		f81232_port_remove,
820 	.suspend =		f81232_suspend,
821 	.resume =		f81232_resume,
822 };
823 
824 static struct usb_serial_driver * const serial_drivers[] = {
825 	&f81232_device,
826 	NULL,
827 };
828 
829 module_usb_serial_driver(serial_drivers, id_table);
830 
831 MODULE_DESCRIPTION("Fintek F81232 USB to serial adaptor driver");
832 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");
833 MODULE_AUTHOR("Peter Hong <peter_hong@fintek.com.tw>");
834 MODULE_LICENSE("GPL v2");
835