xref: /openbmc/linux/drivers/usb/serial/f81534.c (revision 1c2dd16a)
1 /*
2  * F81532/F81534 USB to Serial Ports Bridge
3  *
4  * F81532 => 2 Serial Ports
5  * F81534 => 4 Serial Ports
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * Copyright (C) 2016 Feature Integration Technology Inc., (Fintek)
13  * Copyright (C) 2016 Tom Tsai (Tom_Tsai@fintek.com.tw)
14  * Copyright (C) 2016 Peter Hong (Peter_Hong@fintek.com.tw)
15  *
16  * The F81532/F81534 had 1 control endpoint for setting, 1 endpoint bulk-out
17  * for all serial port TX and 1 endpoint bulk-in for all serial port read in
18  * (Read Data/MSR/LSR).
19  *
20  * Write URB is fixed with 512bytes, per serial port used 128Bytes.
21  * It can be described by f81534_prepare_write_buffer()
22  *
23  * Read URB is 512Bytes max, per serial port used 128Bytes.
24  * It can be described by f81534_process_read_urb() and maybe received with
25  * 128x1,2,3,4 bytes.
26  *
27  */
28 #include <linux/slab.h>
29 #include <linux/tty.h>
30 #include <linux/tty_flip.h>
31 #include <linux/usb.h>
32 #include <linux/usb/serial.h>
33 #include <linux/serial_reg.h>
34 #include <linux/module.h>
35 #include <linux/uaccess.h>
36 
37 /* Serial Port register Address */
38 #define F81534_UART_BASE_ADDRESS	0x1200
39 #define F81534_UART_OFFSET		0x10
40 #define F81534_DIVISOR_LSB_REG		(0x00 + F81534_UART_BASE_ADDRESS)
41 #define F81534_DIVISOR_MSB_REG		(0x01 + F81534_UART_BASE_ADDRESS)
42 #define F81534_FIFO_CONTROL_REG		(0x02 + F81534_UART_BASE_ADDRESS)
43 #define F81534_LINE_CONTROL_REG		(0x03 + F81534_UART_BASE_ADDRESS)
44 #define F81534_MODEM_CONTROL_REG	(0x04 + F81534_UART_BASE_ADDRESS)
45 #define F81534_MODEM_STATUS_REG		(0x06 + F81534_UART_BASE_ADDRESS)
46 #define F81534_CONFIG1_REG		(0x09 + F81534_UART_BASE_ADDRESS)
47 
48 #define F81534_DEF_CONF_ADDRESS_START	0x3000
49 #define F81534_DEF_CONF_SIZE		8
50 
51 #define F81534_CUSTOM_ADDRESS_START	0x2f00
52 #define F81534_CUSTOM_DATA_SIZE		0x10
53 #define F81534_CUSTOM_NO_CUSTOM_DATA	0xff
54 #define F81534_CUSTOM_VALID_TOKEN	0xf0
55 #define F81534_CONF_OFFSET		1
56 
57 #define F81534_MAX_DATA_BLOCK		64
58 #define F81534_MAX_BUS_RETRY		20
59 
60 /* Default URB timeout for USB operations */
61 #define F81534_USB_MAX_RETRY		10
62 #define F81534_USB_TIMEOUT		1000
63 #define F81534_SET_GET_REGISTER		0xA0
64 
65 #define F81534_NUM_PORT			4
66 #define F81534_UNUSED_PORT		0xff
67 #define F81534_WRITE_BUFFER_SIZE	512
68 
69 #define DRIVER_DESC			"Fintek F81532/F81534"
70 #define FINTEK_VENDOR_ID_1		0x1934
71 #define FINTEK_VENDOR_ID_2		0x2C42
72 #define FINTEK_DEVICE_ID		0x1202
73 #define F81534_MAX_TX_SIZE		124
74 #define F81534_MAX_RX_SIZE		124
75 #define F81534_RECEIVE_BLOCK_SIZE	128
76 #define F81534_MAX_RECEIVE_BLOCK_SIZE	512
77 
78 #define F81534_TOKEN_RECEIVE		0x01
79 #define F81534_TOKEN_WRITE		0x02
80 #define F81534_TOKEN_TX_EMPTY		0x03
81 #define F81534_TOKEN_MSR_CHANGE		0x04
82 
83 /*
84  * We used interal SPI bus to access FLASH section. We must wait the SPI bus to
85  * idle if we performed any command.
86  *
87  * SPI Bus status register: F81534_BUS_REG_STATUS
88  *	Bit 0/1	: BUSY
89  *	Bit 2	: IDLE
90  */
91 #define F81534_BUS_BUSY			(BIT(0) | BIT(1))
92 #define F81534_BUS_IDLE			BIT(2)
93 #define F81534_BUS_READ_DATA		0x1004
94 #define F81534_BUS_REG_STATUS		0x1003
95 #define F81534_BUS_REG_START		0x1002
96 #define F81534_BUS_REG_END		0x1001
97 
98 #define F81534_CMD_READ			0x03
99 
100 #define F81534_DEFAULT_BAUD_RATE	9600
101 #define F81534_MAX_BAUDRATE		115200
102 
103 #define F81534_PORT_CONF_DISABLE_PORT	BIT(3)
104 #define F81534_PORT_CONF_NOT_EXIST_PORT	BIT(7)
105 #define F81534_PORT_UNAVAILABLE		\
106 	(F81534_PORT_CONF_DISABLE_PORT | F81534_PORT_CONF_NOT_EXIST_PORT)
107 
108 #define F81534_1X_RXTRIGGER		0xc3
109 #define F81534_8X_RXTRIGGER		0xcf
110 
111 static const struct usb_device_id f81534_id_table[] = {
112 	{ USB_DEVICE(FINTEK_VENDOR_ID_1, FINTEK_DEVICE_ID) },
113 	{ USB_DEVICE(FINTEK_VENDOR_ID_2, FINTEK_DEVICE_ID) },
114 	{}			/* Terminating entry */
115 };
116 
117 #define F81534_TX_EMPTY_BIT		0
118 
119 struct f81534_serial_private {
120 	u8 conf_data[F81534_DEF_CONF_SIZE];
121 	int tty_idx[F81534_NUM_PORT];
122 	u8 setting_idx;
123 	int opened_port;
124 	struct mutex urb_mutex;
125 };
126 
127 struct f81534_port_private {
128 	struct mutex mcr_mutex;
129 	unsigned long tx_empty;
130 	spinlock_t msr_lock;
131 	u8 shadow_mcr;
132 	u8 shadow_msr;
133 	u8 phy_num;
134 };
135 
136 static int f81534_logic_to_phy_port(struct usb_serial *serial,
137 					struct usb_serial_port *port)
138 {
139 	struct f81534_serial_private *serial_priv =
140 			usb_get_serial_data(port->serial);
141 	int count = 0;
142 	int i;
143 
144 	for (i = 0; i < F81534_NUM_PORT; ++i) {
145 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
146 			continue;
147 
148 		if (port->port_number == count)
149 			return i;
150 
151 		++count;
152 	}
153 
154 	return -ENODEV;
155 }
156 
157 static int f81534_set_register(struct usb_serial *serial, u16 reg, u8 data)
158 {
159 	struct usb_interface *interface = serial->interface;
160 	struct usb_device *dev = serial->dev;
161 	size_t count = F81534_USB_MAX_RETRY;
162 	int status;
163 	u8 *tmp;
164 
165 	tmp = kmalloc(sizeof(u8), GFP_KERNEL);
166 	if (!tmp)
167 		return -ENOMEM;
168 
169 	*tmp = data;
170 
171 	/*
172 	 * Our device maybe not reply when heavily loading, We'll retry for
173 	 * F81534_USB_MAX_RETRY times.
174 	 */
175 	while (count--) {
176 		status = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
177 					 F81534_SET_GET_REGISTER,
178 					 USB_TYPE_VENDOR | USB_DIR_OUT,
179 					 reg, 0, tmp, sizeof(u8),
180 					 F81534_USB_TIMEOUT);
181 		if (status > 0) {
182 			status = 0;
183 			break;
184 		} else if (status == 0) {
185 			status = -EIO;
186 		}
187 	}
188 
189 	if (status < 0) {
190 		dev_err(&interface->dev, "%s: reg: %x data: %x failed: %d\n",
191 				__func__, reg, data, status);
192 	}
193 
194 	kfree(tmp);
195 	return status;
196 }
197 
198 static int f81534_get_register(struct usb_serial *serial, u16 reg, u8 *data)
199 {
200 	struct usb_interface *interface = serial->interface;
201 	struct usb_device *dev = serial->dev;
202 	size_t count = F81534_USB_MAX_RETRY;
203 	int status;
204 	u8 *tmp;
205 
206 	tmp = kmalloc(sizeof(u8), GFP_KERNEL);
207 	if (!tmp)
208 		return -ENOMEM;
209 
210 	/*
211 	 * Our device maybe not reply when heavily loading, We'll retry for
212 	 * F81534_USB_MAX_RETRY times.
213 	 */
214 	while (count--) {
215 		status = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
216 					 F81534_SET_GET_REGISTER,
217 					 USB_TYPE_VENDOR | USB_DIR_IN,
218 					 reg, 0, tmp, sizeof(u8),
219 					 F81534_USB_TIMEOUT);
220 		if (status > 0) {
221 			status = 0;
222 			break;
223 		} else if (status == 0) {
224 			status = -EIO;
225 		}
226 	}
227 
228 	if (status < 0) {
229 		dev_err(&interface->dev, "%s: reg: %x failed: %d\n", __func__,
230 				reg, status);
231 		goto end;
232 	}
233 
234 	*data = *tmp;
235 
236 end:
237 	kfree(tmp);
238 	return status;
239 }
240 
241 static int f81534_set_port_register(struct usb_serial_port *port, u16 reg,
242 					u8 data)
243 {
244 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
245 
246 	return f81534_set_register(port->serial,
247 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
248 }
249 
250 static int f81534_get_port_register(struct usb_serial_port *port, u16 reg,
251 					u8 *data)
252 {
253 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
254 
255 	return f81534_get_register(port->serial,
256 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
257 }
258 
259 /*
260  * If we try to access the internal flash via SPI bus, we should check the bus
261  * status for every command. e.g., F81534_BUS_REG_START/F81534_BUS_REG_END
262  */
263 static int f81534_wait_for_spi_idle(struct usb_serial *serial)
264 {
265 	size_t count = F81534_MAX_BUS_RETRY;
266 	u8 tmp;
267 	int status;
268 
269 	do {
270 		status = f81534_get_register(serial, F81534_BUS_REG_STATUS,
271 						&tmp);
272 		if (status)
273 			return status;
274 
275 		if (tmp & F81534_BUS_BUSY)
276 			continue;
277 
278 		if (tmp & F81534_BUS_IDLE)
279 			break;
280 
281 	} while (--count);
282 
283 	if (!count) {
284 		dev_err(&serial->interface->dev,
285 				"%s: timed out waiting for idle SPI bus\n",
286 				__func__);
287 		return -EIO;
288 	}
289 
290 	return f81534_set_register(serial, F81534_BUS_REG_STATUS,
291 				tmp & ~F81534_BUS_IDLE);
292 }
293 
294 static int f81534_get_spi_register(struct usb_serial *serial, u16 reg,
295 					u8 *data)
296 {
297 	int status;
298 
299 	status = f81534_get_register(serial, reg, data);
300 	if (status)
301 		return status;
302 
303 	return f81534_wait_for_spi_idle(serial);
304 }
305 
306 static int f81534_set_spi_register(struct usb_serial *serial, u16 reg, u8 data)
307 {
308 	int status;
309 
310 	status = f81534_set_register(serial, reg, data);
311 	if (status)
312 		return status;
313 
314 	return f81534_wait_for_spi_idle(serial);
315 }
316 
317 static int f81534_read_flash(struct usb_serial *serial, u32 address,
318 				size_t size, u8 *buf)
319 {
320 	u8 tmp_buf[F81534_MAX_DATA_BLOCK];
321 	size_t block = 0;
322 	size_t read_size;
323 	size_t count;
324 	int status;
325 	int offset;
326 	u16 reg_tmp;
327 
328 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
329 					F81534_CMD_READ);
330 	if (status)
331 		return status;
332 
333 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
334 					(address >> 16) & 0xff);
335 	if (status)
336 		return status;
337 
338 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
339 					(address >> 8) & 0xff);
340 	if (status)
341 		return status;
342 
343 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
344 					(address >> 0) & 0xff);
345 	if (status)
346 		return status;
347 
348 	/* Continuous read mode */
349 	do {
350 		read_size = min_t(size_t, F81534_MAX_DATA_BLOCK, size);
351 
352 		for (count = 0; count < read_size; ++count) {
353 			/* To write F81534_BUS_REG_END when final byte */
354 			if (size <= F81534_MAX_DATA_BLOCK &&
355 					read_size == count + 1)
356 				reg_tmp = F81534_BUS_REG_END;
357 			else
358 				reg_tmp = F81534_BUS_REG_START;
359 
360 			/*
361 			 * Dummy code, force IC to generate a read pulse, the
362 			 * set of value 0xf1 is dont care (any value is ok)
363 			 */
364 			status = f81534_set_spi_register(serial, reg_tmp,
365 					0xf1);
366 			if (status)
367 				return status;
368 
369 			status = f81534_get_spi_register(serial,
370 						F81534_BUS_READ_DATA,
371 						&tmp_buf[count]);
372 			if (status)
373 				return status;
374 
375 			offset = count + block * F81534_MAX_DATA_BLOCK;
376 			buf[offset] = tmp_buf[count];
377 		}
378 
379 		size -= read_size;
380 		++block;
381 	} while (size);
382 
383 	return 0;
384 }
385 
386 static void f81534_prepare_write_buffer(struct usb_serial_port *port, u8 *buf)
387 {
388 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
389 	int phy_num = port_priv->phy_num;
390 	u8 tx_len;
391 	int i;
392 
393 	/*
394 	 * The block layout is fixed with 4x128 Bytes, per 128 Bytes a port.
395 	 * index 0: port phy idx (e.g., 0,1,2,3)
396 	 * index 1: only F81534_TOKEN_WRITE
397 	 * index 2: serial TX out length
398 	 * index 3: fix to 0
399 	 * index 4~127: serial out data block
400 	 */
401 	for (i = 0; i < F81534_NUM_PORT; ++i) {
402 		buf[i * F81534_RECEIVE_BLOCK_SIZE] = i;
403 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 1] = F81534_TOKEN_WRITE;
404 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 2] = 0;
405 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 3] = 0;
406 	}
407 
408 	tx_len = kfifo_out_locked(&port->write_fifo,
409 				&buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 4],
410 				F81534_MAX_TX_SIZE, &port->lock);
411 
412 	buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 2] = tx_len;
413 }
414 
415 static int f81534_submit_writer(struct usb_serial_port *port, gfp_t mem_flags)
416 {
417 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
418 	struct urb *urb;
419 	unsigned long flags;
420 	int result;
421 
422 	/* Check is any data in write_fifo */
423 	spin_lock_irqsave(&port->lock, flags);
424 
425 	if (kfifo_is_empty(&port->write_fifo)) {
426 		spin_unlock_irqrestore(&port->lock, flags);
427 		return 0;
428 	}
429 
430 	spin_unlock_irqrestore(&port->lock, flags);
431 
432 	/* Check H/W is TXEMPTY */
433 	if (!test_and_clear_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty))
434 		return 0;
435 
436 	urb = port->write_urbs[0];
437 	f81534_prepare_write_buffer(port, port->bulk_out_buffers[0]);
438 	urb->transfer_buffer_length = F81534_WRITE_BUFFER_SIZE;
439 
440 	result = usb_submit_urb(urb, mem_flags);
441 	if (result) {
442 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
443 		dev_err(&port->dev, "%s: submit failed: %d\n", __func__,
444 				result);
445 		return result;
446 	}
447 
448 	usb_serial_port_softint(port);
449 	return 0;
450 }
451 
452 static u32 f81534_calc_baud_divisor(u32 baudrate, u32 clockrate)
453 {
454 	if (!baudrate)
455 		return 0;
456 
457 	/* Round to nearest divisor */
458 	return DIV_ROUND_CLOSEST(clockrate, baudrate);
459 }
460 
461 static int f81534_set_port_config(struct usb_serial_port *port, u32 baudrate,
462 					u8 lcr)
463 {
464 	u32 divisor;
465 	int status;
466 	u8 value;
467 
468 	if (baudrate <= 1200)
469 		value = F81534_1X_RXTRIGGER;	/* 128 FIFO & TL: 1x */
470 	else
471 		value = F81534_8X_RXTRIGGER;	/* 128 FIFO & TL: 8x */
472 
473 	status = f81534_set_port_register(port, F81534_CONFIG1_REG, value);
474 	if (status) {
475 		dev_err(&port->dev, "%s: CONFIG1 setting failed\n", __func__);
476 		return status;
477 	}
478 
479 	if (baudrate <= 1200)
480 		value = UART_FCR_TRIGGER_1 | UART_FCR_ENABLE_FIFO; /* TL: 1 */
481 	else
482 		value = UART_FCR_R_TRIG_11 | UART_FCR_ENABLE_FIFO; /* TL: 14 */
483 
484 	status = f81534_set_port_register(port, F81534_FIFO_CONTROL_REG,
485 						value);
486 	if (status) {
487 		dev_err(&port->dev, "%s: FCR setting failed\n", __func__);
488 		return status;
489 	}
490 
491 	divisor = f81534_calc_baud_divisor(baudrate, F81534_MAX_BAUDRATE);
492 	value = UART_LCR_DLAB;
493 	status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG,
494 						value);
495 	if (status) {
496 		dev_err(&port->dev, "%s: set LCR failed\n", __func__);
497 		return status;
498 	}
499 
500 	value = divisor & 0xff;
501 	status = f81534_set_port_register(port, F81534_DIVISOR_LSB_REG, value);
502 	if (status) {
503 		dev_err(&port->dev, "%s: set DLAB LSB failed\n", __func__);
504 		return status;
505 	}
506 
507 	value = (divisor >> 8) & 0xff;
508 	status = f81534_set_port_register(port, F81534_DIVISOR_MSB_REG, value);
509 	if (status) {
510 		dev_err(&port->dev, "%s: set DLAB MSB failed\n", __func__);
511 		return status;
512 	}
513 
514 	status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG, lcr);
515 	if (status) {
516 		dev_err(&port->dev, "%s: set LCR failed\n", __func__);
517 		return status;
518 	}
519 
520 	return 0;
521 }
522 
523 static int f81534_update_mctrl(struct usb_serial_port *port, unsigned int set,
524 				unsigned int clear)
525 {
526 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
527 	int status;
528 	u8 tmp;
529 
530 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
531 		return 0;	/* no change */
532 
533 	mutex_lock(&port_priv->mcr_mutex);
534 
535 	/* 'Set' takes precedence over 'Clear' */
536 	clear &= ~set;
537 
538 	/* Always enable UART_MCR_OUT2 */
539 	tmp = UART_MCR_OUT2 | port_priv->shadow_mcr;
540 
541 	if (clear & TIOCM_DTR)
542 		tmp &= ~UART_MCR_DTR;
543 
544 	if (clear & TIOCM_RTS)
545 		tmp &= ~UART_MCR_RTS;
546 
547 	if (set & TIOCM_DTR)
548 		tmp |= UART_MCR_DTR;
549 
550 	if (set & TIOCM_RTS)
551 		tmp |= UART_MCR_RTS;
552 
553 	status = f81534_set_port_register(port, F81534_MODEM_CONTROL_REG, tmp);
554 	if (status < 0) {
555 		dev_err(&port->dev, "%s: MCR write failed\n", __func__);
556 		mutex_unlock(&port_priv->mcr_mutex);
557 		return status;
558 	}
559 
560 	port_priv->shadow_mcr = tmp;
561 	mutex_unlock(&port_priv->mcr_mutex);
562 	return 0;
563 }
564 
565 /*
566  * This function will search the data area with token F81534_CUSTOM_VALID_TOKEN
567  * for latest configuration index. If nothing found
568  * (*index = F81534_CUSTOM_NO_CUSTOM_DATA), We'll load default configure in
569  * F81534_DEF_CONF_ADDRESS_START section.
570  *
571  * Due to we only use block0 to save data, so *index should be 0 or
572  * F81534_CUSTOM_NO_CUSTOM_DATA.
573  */
574 static int f81534_find_config_idx(struct usb_serial *serial, u8 *index)
575 {
576 	u8 tmp;
577 	int status;
578 
579 	status = f81534_read_flash(serial, F81534_CUSTOM_ADDRESS_START, 1,
580 					&tmp);
581 	if (status) {
582 		dev_err(&serial->interface->dev, "%s: read failed: %d\n",
583 				__func__, status);
584 		return status;
585 	}
586 
587 	/* We'll use the custom data when the data is valid. */
588 	if (tmp == F81534_CUSTOM_VALID_TOKEN)
589 		*index = 0;
590 	else
591 		*index = F81534_CUSTOM_NO_CUSTOM_DATA;
592 
593 	return 0;
594 }
595 
596 /*
597  * We had 2 generation of F81532/534 IC. All has an internal storage.
598  *
599  * 1st is pure USB-to-TTL RS232 IC and designed for 4 ports only, no any
600  * internal data will used. All mode and gpio control should manually set
601  * by AP or Driver and all storage space value are 0xff. The
602  * f81534_calc_num_ports() will run to final we marked as "oldest version"
603  * for this IC.
604  *
605  * 2rd is designed to more generic to use any transceiver and this is our
606  * mass production type. We'll save data in F81534_CUSTOM_ADDRESS_START
607  * (0x2f00) with 9bytes. The 1st byte is a indicater. If the token is
608  * F81534_CUSTOM_VALID_TOKEN(0xf0), the IC is 2nd gen type, the following
609  * 4bytes save port mode (0:RS232/1:RS485 Invert/2:RS485), and the last
610  * 4bytes save GPIO state(value from 0~7 to represent 3 GPIO output pin).
611  * The f81534_calc_num_ports() will run to "new style" with checking
612  * F81534_PORT_UNAVAILABLE section.
613  */
614 static int f81534_calc_num_ports(struct usb_serial *serial)
615 {
616 	u8 setting[F81534_CUSTOM_DATA_SIZE];
617 	u8 setting_idx;
618 	u8 num_port = 0;
619 	int status;
620 	size_t i;
621 
622 	/* Check had custom setting */
623 	status = f81534_find_config_idx(serial, &setting_idx);
624 	if (status) {
625 		dev_err(&serial->interface->dev, "%s: find idx failed: %d\n",
626 				__func__, status);
627 		return 0;
628 	}
629 
630 	/*
631 	 * We'll read custom data only when data available, otherwise we'll
632 	 * read default value instead.
633 	 */
634 	if (setting_idx != F81534_CUSTOM_NO_CUSTOM_DATA) {
635 		status = f81534_read_flash(serial,
636 						F81534_CUSTOM_ADDRESS_START +
637 						F81534_CONF_OFFSET,
638 						sizeof(setting), setting);
639 		if (status) {
640 			dev_err(&serial->interface->dev,
641 					"%s: get custom data failed: %d\n",
642 					__func__, status);
643 			return 0;
644 		}
645 
646 		dev_dbg(&serial->interface->dev,
647 				"%s: read config from block: %d\n", __func__,
648 				setting_idx);
649 	} else {
650 		/* Read default board setting */
651 		status = f81534_read_flash(serial,
652 				F81534_DEF_CONF_ADDRESS_START, F81534_NUM_PORT,
653 				setting);
654 
655 		if (status) {
656 			dev_err(&serial->interface->dev,
657 					"%s: read failed: %d\n", __func__,
658 					status);
659 			return 0;
660 		}
661 
662 		dev_dbg(&serial->interface->dev, "%s: read default config\n",
663 				__func__);
664 	}
665 
666 	/* New style, find all possible ports */
667 	for (i = 0; i < F81534_NUM_PORT; ++i) {
668 		if (setting[i] & F81534_PORT_UNAVAILABLE)
669 			continue;
670 
671 		++num_port;
672 	}
673 
674 	if (num_port)
675 		return num_port;
676 
677 	dev_warn(&serial->interface->dev, "%s: Read Failed. default 4 ports\n",
678 			__func__);
679 	return 4;		/* Nothing found, oldest version IC */
680 }
681 
682 static void f81534_set_termios(struct tty_struct *tty,
683 				struct usb_serial_port *port,
684 				struct ktermios *old_termios)
685 {
686 	u8 new_lcr = 0;
687 	int status;
688 	u32 baud;
689 
690 	if (C_BAUD(tty) == B0)
691 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
692 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
693 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
694 
695 	if (C_PARENB(tty)) {
696 		new_lcr |= UART_LCR_PARITY;
697 
698 		if (!C_PARODD(tty))
699 			new_lcr |= UART_LCR_EPAR;
700 
701 		if (C_CMSPAR(tty))
702 			new_lcr |= UART_LCR_SPAR;
703 	}
704 
705 	if (C_CSTOPB(tty))
706 		new_lcr |= UART_LCR_STOP;
707 
708 	switch (C_CSIZE(tty)) {
709 	case CS5:
710 		new_lcr |= UART_LCR_WLEN5;
711 		break;
712 	case CS6:
713 		new_lcr |= UART_LCR_WLEN6;
714 		break;
715 	case CS7:
716 		new_lcr |= UART_LCR_WLEN7;
717 		break;
718 	default:
719 	case CS8:
720 		new_lcr |= UART_LCR_WLEN8;
721 		break;
722 	}
723 
724 	baud = tty_get_baud_rate(tty);
725 	if (!baud)
726 		return;
727 
728 	if (baud > F81534_MAX_BAUDRATE) {
729 		if (old_termios)
730 			baud = tty_termios_baud_rate(old_termios);
731 		else
732 			baud = F81534_DEFAULT_BAUD_RATE;
733 
734 		tty_encode_baud_rate(tty, baud, baud);
735 	}
736 
737 	dev_dbg(&port->dev, "%s: baud: %d\n", __func__, baud);
738 
739 	status = f81534_set_port_config(port, baud, new_lcr);
740 	if (status < 0) {
741 		dev_err(&port->dev, "%s: set port config failed: %d\n",
742 				__func__, status);
743 	}
744 }
745 
746 static int f81534_submit_read_urb(struct usb_serial *serial, gfp_t flags)
747 {
748 	return usb_serial_generic_submit_read_urbs(serial->port[0], flags);
749 }
750 
751 static void f81534_msr_changed(struct usb_serial_port *port, u8 msr)
752 {
753 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
754 	struct tty_struct *tty;
755 	unsigned long flags;
756 	u8 old_msr;
757 
758 	if (!(msr & UART_MSR_ANY_DELTA))
759 		return;
760 
761 	spin_lock_irqsave(&port_priv->msr_lock, flags);
762 	old_msr = port_priv->shadow_msr;
763 	port_priv->shadow_msr = msr;
764 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
765 
766 	dev_dbg(&port->dev, "%s: MSR from %02x to %02x\n", __func__, old_msr,
767 			msr);
768 
769 	/* Update input line counters */
770 	if (msr & UART_MSR_DCTS)
771 		port->icount.cts++;
772 	if (msr & UART_MSR_DDSR)
773 		port->icount.dsr++;
774 	if (msr & UART_MSR_DDCD)
775 		port->icount.dcd++;
776 	if (msr & UART_MSR_TERI)
777 		port->icount.rng++;
778 
779 	wake_up_interruptible(&port->port.delta_msr_wait);
780 
781 	if (!(msr & UART_MSR_DDCD))
782 		return;
783 
784 	dev_dbg(&port->dev, "%s: DCD Changed: phy_num: %d from %x to %x\n",
785 			__func__, port_priv->phy_num, old_msr, msr);
786 
787 	tty = tty_port_tty_get(&port->port);
788 	if (!tty)
789 		return;
790 
791 	usb_serial_handle_dcd_change(port, tty, msr & UART_MSR_DCD);
792 	tty_kref_put(tty);
793 }
794 
795 static int f81534_read_msr(struct usb_serial_port *port)
796 {
797 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
798 	unsigned long flags;
799 	int status;
800 	u8 msr;
801 
802 	/* Get MSR initial value */
803 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
804 	if (status)
805 		return status;
806 
807 	/* Force update current state */
808 	spin_lock_irqsave(&port_priv->msr_lock, flags);
809 	port_priv->shadow_msr = msr;
810 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
811 
812 	return 0;
813 }
814 
815 static int f81534_open(struct tty_struct *tty, struct usb_serial_port *port)
816 {
817 	struct f81534_serial_private *serial_priv =
818 			usb_get_serial_data(port->serial);
819 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
820 	int status;
821 
822 	status = f81534_set_port_register(port,
823 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
824 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
825 	if (status) {
826 		dev_err(&port->dev, "%s: Clear FIFO failed: %d\n", __func__,
827 				status);
828 		return status;
829 	}
830 
831 	if (tty)
832 		f81534_set_termios(tty, port, NULL);
833 
834 	status = f81534_read_msr(port);
835 	if (status)
836 		return status;
837 
838 	mutex_lock(&serial_priv->urb_mutex);
839 
840 	/* Submit Read URBs for first port opened */
841 	if (!serial_priv->opened_port) {
842 		status = f81534_submit_read_urb(port->serial, GFP_KERNEL);
843 		if (status)
844 			goto exit;
845 	}
846 
847 	serial_priv->opened_port++;
848 
849 exit:
850 	mutex_unlock(&serial_priv->urb_mutex);
851 
852 	set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
853 	return status;
854 }
855 
856 static void f81534_close(struct usb_serial_port *port)
857 {
858 	struct f81534_serial_private *serial_priv =
859 			usb_get_serial_data(port->serial);
860 	struct usb_serial_port *port0 = port->serial->port[0];
861 	unsigned long flags;
862 	size_t i;
863 
864 	usb_kill_urb(port->write_urbs[0]);
865 
866 	spin_lock_irqsave(&port->lock, flags);
867 	kfifo_reset_out(&port->write_fifo);
868 	spin_unlock_irqrestore(&port->lock, flags);
869 
870 	/* Kill Read URBs when final port closed */
871 	mutex_lock(&serial_priv->urb_mutex);
872 	serial_priv->opened_port--;
873 
874 	if (!serial_priv->opened_port) {
875 		for (i = 0; i < ARRAY_SIZE(port0->read_urbs); ++i)
876 			usb_kill_urb(port0->read_urbs[i]);
877 	}
878 
879 	mutex_unlock(&serial_priv->urb_mutex);
880 }
881 
882 static int f81534_get_serial_info(struct usb_serial_port *port,
883 				  struct serial_struct __user *retinfo)
884 {
885 	struct f81534_port_private *port_priv;
886 	struct serial_struct tmp;
887 
888 	port_priv = usb_get_serial_port_data(port);
889 
890 	memset(&tmp, 0, sizeof(tmp));
891 
892 	tmp.type = PORT_16550A;
893 	tmp.port = port->port_number;
894 	tmp.line = port->minor;
895 	tmp.baud_base = F81534_MAX_BAUDRATE;
896 
897 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
898 		return -EFAULT;
899 
900 	return 0;
901 }
902 
903 static int f81534_ioctl(struct tty_struct *tty, unsigned int cmd,
904 			unsigned long arg)
905 {
906 	struct usb_serial_port *port = tty->driver_data;
907 	struct serial_struct __user *buf = (struct serial_struct __user *)arg;
908 
909 	switch (cmd) {
910 	case TIOCGSERIAL:
911 		return f81534_get_serial_info(port, buf);
912 	default:
913 		break;
914 	}
915 
916 	return -ENOIOCTLCMD;
917 }
918 
919 static void f81534_process_per_serial_block(struct usb_serial_port *port,
920 		u8 *data)
921 {
922 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
923 	int phy_num = data[0];
924 	size_t read_size = 0;
925 	size_t i;
926 	char tty_flag;
927 	int status;
928 	u8 lsr;
929 
930 	/*
931 	 * The block layout is 128 Bytes
932 	 * index 0: port phy idx (e.g., 0,1,2,3),
933 	 * index 1: It's could be
934 	 *			F81534_TOKEN_RECEIVE
935 	 *			F81534_TOKEN_TX_EMPTY
936 	 *			F81534_TOKEN_MSR_CHANGE
937 	 * index 2: serial in size (data+lsr, must be even)
938 	 *			meaningful for F81534_TOKEN_RECEIVE only
939 	 * index 3: current MSR with this device
940 	 * index 4~127: serial in data block (data+lsr, must be even)
941 	 */
942 	switch (data[1]) {
943 	case F81534_TOKEN_TX_EMPTY:
944 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
945 
946 		/* Try to submit writer */
947 		status = f81534_submit_writer(port, GFP_ATOMIC);
948 		if (status)
949 			dev_err(&port->dev, "%s: submit failed\n", __func__);
950 		return;
951 
952 	case F81534_TOKEN_MSR_CHANGE:
953 		f81534_msr_changed(port, data[3]);
954 		return;
955 
956 	case F81534_TOKEN_RECEIVE:
957 		read_size = data[2];
958 		if (read_size > F81534_MAX_RX_SIZE) {
959 			dev_err(&port->dev,
960 				"%s: phy: %d read_size: %zu larger than: %d\n",
961 				__func__, phy_num, read_size,
962 				F81534_MAX_RX_SIZE);
963 			return;
964 		}
965 
966 		break;
967 
968 	default:
969 		dev_warn(&port->dev, "%s: unknown token: %02x\n", __func__,
970 				data[1]);
971 		return;
972 	}
973 
974 	for (i = 4; i < 4 + read_size; i += 2) {
975 		tty_flag = TTY_NORMAL;
976 		lsr = data[i + 1];
977 
978 		if (lsr & UART_LSR_BRK_ERROR_BITS) {
979 			if (lsr & UART_LSR_BI) {
980 				tty_flag = TTY_BREAK;
981 				port->icount.brk++;
982 				usb_serial_handle_break(port);
983 			} else if (lsr & UART_LSR_PE) {
984 				tty_flag = TTY_PARITY;
985 				port->icount.parity++;
986 			} else if (lsr & UART_LSR_FE) {
987 				tty_flag = TTY_FRAME;
988 				port->icount.frame++;
989 			}
990 
991 			if (lsr & UART_LSR_OE) {
992 				port->icount.overrun++;
993 				tty_insert_flip_char(&port->port, 0,
994 						TTY_OVERRUN);
995 			}
996 		}
997 
998 		if (port->port.console && port->sysrq) {
999 			if (usb_serial_handle_sysrq_char(port, data[i]))
1000 				continue;
1001 		}
1002 
1003 		tty_insert_flip_char(&port->port, data[i], tty_flag);
1004 	}
1005 
1006 	tty_flip_buffer_push(&port->port);
1007 }
1008 
1009 static void f81534_process_read_urb(struct urb *urb)
1010 {
1011 	struct f81534_serial_private *serial_priv;
1012 	struct usb_serial_port *port;
1013 	struct usb_serial *serial;
1014 	u8 *buf;
1015 	int phy_port_num;
1016 	int tty_port_num;
1017 	size_t i;
1018 
1019 	if (!urb->actual_length ||
1020 			urb->actual_length % F81534_RECEIVE_BLOCK_SIZE) {
1021 		return;
1022 	}
1023 
1024 	port = urb->context;
1025 	serial = port->serial;
1026 	buf = urb->transfer_buffer;
1027 	serial_priv = usb_get_serial_data(serial);
1028 
1029 	for (i = 0; i < urb->actual_length; i += F81534_RECEIVE_BLOCK_SIZE) {
1030 		phy_port_num = buf[i];
1031 		if (phy_port_num >= F81534_NUM_PORT) {
1032 			dev_err(&port->dev,
1033 				"%s: phy_port_num: %d larger than: %d\n",
1034 				__func__, phy_port_num, F81534_NUM_PORT);
1035 			continue;
1036 		}
1037 
1038 		tty_port_num = serial_priv->tty_idx[phy_port_num];
1039 		port = serial->port[tty_port_num];
1040 
1041 		if (tty_port_initialized(&port->port))
1042 			f81534_process_per_serial_block(port, &buf[i]);
1043 	}
1044 }
1045 
1046 static void f81534_write_usb_callback(struct urb *urb)
1047 {
1048 	struct usb_serial_port *port = urb->context;
1049 
1050 	switch (urb->status) {
1051 	case 0:
1052 		break;
1053 	case -ENOENT:
1054 	case -ECONNRESET:
1055 	case -ESHUTDOWN:
1056 		dev_dbg(&port->dev, "%s - urb stopped: %d\n",
1057 				__func__, urb->status);
1058 		return;
1059 	case -EPIPE:
1060 		dev_err(&port->dev, "%s - urb stopped: %d\n",
1061 				__func__, urb->status);
1062 		return;
1063 	default:
1064 		dev_dbg(&port->dev, "%s - nonzero urb status: %d\n",
1065 				__func__, urb->status);
1066 		break;
1067 	}
1068 }
1069 
1070 static int f81534_setup_ports(struct usb_serial *serial)
1071 {
1072 	struct usb_serial_port *port;
1073 	u8 port0_out_address;
1074 	int buffer_size;
1075 	size_t i;
1076 
1077 	/*
1078 	 * In our system architecture, we had 2 or 4 serial ports,
1079 	 * but only get 1 set of bulk in/out endpoints.
1080 	 *
1081 	 * The usb-serial subsystem will generate port 0 data,
1082 	 * but port 1/2/3 will not. It's will generate write URB and buffer
1083 	 * by following code and use the port0 read URB for read operation.
1084 	 */
1085 	for (i = 1; i < serial->num_ports; ++i) {
1086 		port0_out_address = serial->port[0]->bulk_out_endpointAddress;
1087 		buffer_size = serial->port[0]->bulk_out_size;
1088 		port = serial->port[i];
1089 
1090 		if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
1091 			return -ENOMEM;
1092 
1093 		port->bulk_out_size = buffer_size;
1094 		port->bulk_out_endpointAddress = port0_out_address;
1095 
1096 		port->write_urbs[0] = usb_alloc_urb(0, GFP_KERNEL);
1097 		if (!port->write_urbs[0])
1098 			return -ENOMEM;
1099 
1100 		port->bulk_out_buffers[0] = kzalloc(buffer_size, GFP_KERNEL);
1101 		if (!port->bulk_out_buffers[0])
1102 			return -ENOMEM;
1103 
1104 		usb_fill_bulk_urb(port->write_urbs[0], serial->dev,
1105 				usb_sndbulkpipe(serial->dev,
1106 					port0_out_address),
1107 				port->bulk_out_buffers[0], buffer_size,
1108 				serial->type->write_bulk_callback, port);
1109 
1110 		port->write_urb = port->write_urbs[0];
1111 		port->bulk_out_buffer = port->bulk_out_buffers[0];
1112 	}
1113 
1114 	return 0;
1115 }
1116 
1117 static int f81534_probe(struct usb_serial *serial,
1118 					const struct usb_device_id *id)
1119 {
1120 	struct usb_endpoint_descriptor *endpoint;
1121 	struct usb_host_interface *iface_desc;
1122 	struct device *dev;
1123 	int num_bulk_in = 0;
1124 	int num_bulk_out = 0;
1125 	int size_bulk_in = 0;
1126 	int size_bulk_out = 0;
1127 	int i;
1128 
1129 	dev = &serial->interface->dev;
1130 	iface_desc = serial->interface->cur_altsetting;
1131 
1132 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1133 		endpoint = &iface_desc->endpoint[i].desc;
1134 
1135 		if (usb_endpoint_is_bulk_in(endpoint)) {
1136 			++num_bulk_in;
1137 			size_bulk_in = usb_endpoint_maxp(endpoint);
1138 		}
1139 
1140 		if (usb_endpoint_is_bulk_out(endpoint)) {
1141 			++num_bulk_out;
1142 			size_bulk_out = usb_endpoint_maxp(endpoint);
1143 		}
1144 	}
1145 
1146 	if (num_bulk_in != 1 || num_bulk_out != 1) {
1147 		dev_err(dev, "expected endpoints not found\n");
1148 		return -ENODEV;
1149 	}
1150 
1151 	if (size_bulk_out != F81534_WRITE_BUFFER_SIZE ||
1152 			size_bulk_in != F81534_MAX_RECEIVE_BLOCK_SIZE) {
1153 		dev_err(dev, "unsupported endpoint max packet size\n");
1154 		return -ENODEV;
1155 	}
1156 
1157 	return 0;
1158 }
1159 
1160 static int f81534_attach(struct usb_serial *serial)
1161 {
1162 	struct f81534_serial_private *serial_priv;
1163 	int index = 0;
1164 	int status;
1165 	int i;
1166 
1167 	serial_priv = devm_kzalloc(&serial->interface->dev,
1168 					sizeof(*serial_priv), GFP_KERNEL);
1169 	if (!serial_priv)
1170 		return -ENOMEM;
1171 
1172 	usb_set_serial_data(serial, serial_priv);
1173 
1174 	mutex_init(&serial_priv->urb_mutex);
1175 
1176 	status = f81534_setup_ports(serial);
1177 	if (status)
1178 		return status;
1179 
1180 	/* Check had custom setting */
1181 	status = f81534_find_config_idx(serial, &serial_priv->setting_idx);
1182 	if (status) {
1183 		dev_err(&serial->interface->dev, "%s: find idx failed: %d\n",
1184 				__func__, status);
1185 		return status;
1186 	}
1187 
1188 	/*
1189 	 * We'll read custom data only when data available, otherwise we'll
1190 	 * read default value instead.
1191 	 */
1192 	if (serial_priv->setting_idx == F81534_CUSTOM_NO_CUSTOM_DATA) {
1193 		/*
1194 		 * The default configuration layout:
1195 		 *	byte 0/1/2/3: uart setting
1196 		 */
1197 		status = f81534_read_flash(serial,
1198 					F81534_DEF_CONF_ADDRESS_START,
1199 					F81534_DEF_CONF_SIZE,
1200 					serial_priv->conf_data);
1201 		if (status) {
1202 			dev_err(&serial->interface->dev,
1203 					"%s: read reserve data failed: %d\n",
1204 					__func__, status);
1205 			return status;
1206 		}
1207 	} else {
1208 		/* Only read 8 bytes for mode & GPIO */
1209 		status = f81534_read_flash(serial,
1210 						F81534_CUSTOM_ADDRESS_START +
1211 						F81534_CONF_OFFSET,
1212 						sizeof(serial_priv->conf_data),
1213 						serial_priv->conf_data);
1214 		if (status) {
1215 			dev_err(&serial->interface->dev,
1216 					"%s: idx: %d get data failed: %d\n",
1217 					__func__, serial_priv->setting_idx,
1218 					status);
1219 			return status;
1220 		}
1221 	}
1222 
1223 	/* Assign phy-to-logic mapping */
1224 	for (i = 0; i < F81534_NUM_PORT; ++i) {
1225 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
1226 			continue;
1227 
1228 		serial_priv->tty_idx[i] = index++;
1229 		dev_dbg(&serial->interface->dev,
1230 				"%s: phy_num: %d, tty_idx: %d\n", __func__, i,
1231 				serial_priv->tty_idx[i]);
1232 	}
1233 
1234 	return 0;
1235 }
1236 
1237 static int f81534_port_probe(struct usb_serial_port *port)
1238 {
1239 	struct f81534_port_private *port_priv;
1240 	int ret;
1241 
1242 	port_priv = devm_kzalloc(&port->dev, sizeof(*port_priv), GFP_KERNEL);
1243 	if (!port_priv)
1244 		return -ENOMEM;
1245 
1246 	spin_lock_init(&port_priv->msr_lock);
1247 	mutex_init(&port_priv->mcr_mutex);
1248 
1249 	/* Assign logic-to-phy mapping */
1250 	ret = f81534_logic_to_phy_port(port->serial, port);
1251 	if (ret < 0)
1252 		return ret;
1253 
1254 	port_priv->phy_num = ret;
1255 	usb_set_serial_port_data(port, port_priv);
1256 	dev_dbg(&port->dev, "%s: port_number: %d, phy_num: %d\n", __func__,
1257 			port->port_number, port_priv->phy_num);
1258 
1259 	return 0;
1260 }
1261 
1262 static int f81534_tiocmget(struct tty_struct *tty)
1263 {
1264 	struct usb_serial_port *port = tty->driver_data;
1265 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1266 	int status;
1267 	int r;
1268 	u8 msr;
1269 	u8 mcr;
1270 
1271 	/* Read current MSR from device */
1272 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1273 	if (status)
1274 		return status;
1275 
1276 	mutex_lock(&port_priv->mcr_mutex);
1277 	mcr = port_priv->shadow_mcr;
1278 	mutex_unlock(&port_priv->mcr_mutex);
1279 
1280 	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
1281 	    (mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
1282 	    (msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
1283 	    (msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
1284 	    (msr & UART_MSR_RI ? TIOCM_RI : 0) |
1285 	    (msr & UART_MSR_DSR ? TIOCM_DSR : 0);
1286 
1287 	return r;
1288 }
1289 
1290 static int f81534_tiocmset(struct tty_struct *tty, unsigned int set,
1291 				unsigned int clear)
1292 {
1293 	struct usb_serial_port *port = tty->driver_data;
1294 
1295 	return f81534_update_mctrl(port, set, clear);
1296 }
1297 
1298 static void f81534_dtr_rts(struct usb_serial_port *port, int on)
1299 {
1300 	if (on)
1301 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
1302 	else
1303 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
1304 }
1305 
1306 static int f81534_write(struct tty_struct *tty, struct usb_serial_port *port,
1307 			const u8 *buf, int count)
1308 {
1309 	int bytes_out, status;
1310 
1311 	if (!count)
1312 		return 0;
1313 
1314 	bytes_out = kfifo_in_locked(&port->write_fifo, buf, count,
1315 					&port->lock);
1316 
1317 	status = f81534_submit_writer(port, GFP_ATOMIC);
1318 	if (status) {
1319 		dev_err(&port->dev, "%s: submit failed\n", __func__);
1320 		return status;
1321 	}
1322 
1323 	return bytes_out;
1324 }
1325 
1326 static bool f81534_tx_empty(struct usb_serial_port *port)
1327 {
1328 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1329 
1330 	return test_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1331 }
1332 
1333 static int f81534_resume(struct usb_serial *serial)
1334 {
1335 	struct f81534_serial_private *serial_priv =
1336 			usb_get_serial_data(serial);
1337 	struct usb_serial_port *port;
1338 	int error = 0;
1339 	int status;
1340 	size_t i;
1341 
1342 	/*
1343 	 * We'll register port 0 bulkin when port had opened, It'll take all
1344 	 * port received data, MSR register change and TX_EMPTY information.
1345 	 */
1346 	mutex_lock(&serial_priv->urb_mutex);
1347 
1348 	if (serial_priv->opened_port) {
1349 		status = f81534_submit_read_urb(serial, GFP_NOIO);
1350 		if (status) {
1351 			mutex_unlock(&serial_priv->urb_mutex);
1352 			return status;
1353 		}
1354 	}
1355 
1356 	mutex_unlock(&serial_priv->urb_mutex);
1357 
1358 	for (i = 0; i < serial->num_ports; i++) {
1359 		port = serial->port[i];
1360 		if (!tty_port_initialized(&port->port))
1361 			continue;
1362 
1363 		status = f81534_submit_writer(port, GFP_NOIO);
1364 		if (status) {
1365 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1366 			++error;
1367 		}
1368 	}
1369 
1370 	if (error)
1371 		return -EIO;
1372 
1373 	return 0;
1374 }
1375 
1376 static struct usb_serial_driver f81534_device = {
1377 	.driver = {
1378 		   .owner = THIS_MODULE,
1379 		   .name = "f81534",
1380 	},
1381 	.description =		DRIVER_DESC,
1382 	.id_table =		f81534_id_table,
1383 	.open =			f81534_open,
1384 	.close =		f81534_close,
1385 	.write =		f81534_write,
1386 	.tx_empty =		f81534_tx_empty,
1387 	.calc_num_ports =	f81534_calc_num_ports,
1388 	.probe =		f81534_probe,
1389 	.attach =		f81534_attach,
1390 	.port_probe =		f81534_port_probe,
1391 	.dtr_rts =		f81534_dtr_rts,
1392 	.process_read_urb =	f81534_process_read_urb,
1393 	.ioctl =		f81534_ioctl,
1394 	.tiocmget =		f81534_tiocmget,
1395 	.tiocmset =		f81534_tiocmset,
1396 	.write_bulk_callback =	f81534_write_usb_callback,
1397 	.set_termios =		f81534_set_termios,
1398 	.resume =		f81534_resume,
1399 };
1400 
1401 static struct usb_serial_driver *const serial_drivers[] = {
1402 	&f81534_device, NULL
1403 };
1404 
1405 module_usb_serial_driver(serial_drivers, f81534_id_table);
1406 
1407 MODULE_DEVICE_TABLE(usb, f81534_id_table);
1408 MODULE_DESCRIPTION(DRIVER_DESC);
1409 MODULE_AUTHOR("Peter Hong <Peter_Hong@fintek.com.tw>");
1410 MODULE_AUTHOR("Tom Tsai <Tom_Tsai@fintek.com.tw>");
1411 MODULE_LICENSE("GPL");
1412