xref: /linux/drivers/usb/serial/f81534.c (revision e80a48bade619ec5a92230b3d4ae84bfc2746822)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * F81532/F81534 USB to Serial Ports Bridge
4  *
5  * F81532 => 2 Serial Ports
6  * F81534 => 4 Serial Ports
7  *
8  * Copyright (C) 2016 Feature Integration Technology Inc., (Fintek)
9  * Copyright (C) 2016 Tom Tsai (Tom_Tsai@fintek.com.tw)
10  * Copyright (C) 2016 Peter Hong (Peter_Hong@fintek.com.tw)
11  *
12  * The F81532/F81534 had 1 control endpoint for setting, 1 endpoint bulk-out
13  * for all serial port TX and 1 endpoint bulk-in for all serial port read in
14  * (Read Data/MSR/LSR).
15  *
16  * Write URB is fixed with 512bytes, per serial port used 128Bytes.
17  * It can be described by f81534_prepare_write_buffer()
18  *
19  * Read URB is 512Bytes max, per serial port used 128Bytes.
20  * It can be described by f81534_process_read_urb() and maybe received with
21  * 128x1,2,3,4 bytes.
22  *
23  */
24 #include <linux/slab.h>
25 #include <linux/tty.h>
26 #include <linux/tty_flip.h>
27 #include <linux/usb.h>
28 #include <linux/usb/serial.h>
29 #include <linux/serial_reg.h>
30 #include <linux/module.h>
31 #include <linux/uaccess.h>
32 
33 /* Serial Port register Address */
34 #define F81534_UART_BASE_ADDRESS	0x1200
35 #define F81534_UART_OFFSET		0x10
36 #define F81534_DIVISOR_LSB_REG		(0x00 + F81534_UART_BASE_ADDRESS)
37 #define F81534_DIVISOR_MSB_REG		(0x01 + F81534_UART_BASE_ADDRESS)
38 #define F81534_INTERRUPT_ENABLE_REG	(0x01 + F81534_UART_BASE_ADDRESS)
39 #define F81534_FIFO_CONTROL_REG		(0x02 + F81534_UART_BASE_ADDRESS)
40 #define F81534_LINE_CONTROL_REG		(0x03 + F81534_UART_BASE_ADDRESS)
41 #define F81534_MODEM_CONTROL_REG	(0x04 + F81534_UART_BASE_ADDRESS)
42 #define F81534_LINE_STATUS_REG		(0x05 + F81534_UART_BASE_ADDRESS)
43 #define F81534_MODEM_STATUS_REG		(0x06 + F81534_UART_BASE_ADDRESS)
44 #define F81534_CLOCK_REG		(0x08 + F81534_UART_BASE_ADDRESS)
45 #define F81534_CONFIG1_REG		(0x09 + F81534_UART_BASE_ADDRESS)
46 
47 #define F81534_DEF_CONF_ADDRESS_START	0x3000
48 #define F81534_DEF_CONF_SIZE		12
49 
50 #define F81534_CUSTOM_ADDRESS_START	0x2f00
51 #define F81534_CUSTOM_DATA_SIZE		0x10
52 #define F81534_CUSTOM_NO_CUSTOM_DATA	0xff
53 #define F81534_CUSTOM_VALID_TOKEN	0xf0
54 #define F81534_CONF_OFFSET		1
55 #define F81534_CONF_INIT_GPIO_OFFSET	4
56 #define F81534_CONF_WORK_GPIO_OFFSET	8
57 #define F81534_CONF_GPIO_SHUTDOWN	7
58 #define F81534_CONF_GPIO_RS232		1
59 
60 #define F81534_MAX_DATA_BLOCK		64
61 #define F81534_MAX_BUS_RETRY		20
62 
63 /* Default URB timeout for USB operations */
64 #define F81534_USB_MAX_RETRY		10
65 #define F81534_USB_TIMEOUT		2000
66 #define F81534_SET_GET_REGISTER		0xA0
67 
68 #define F81534_NUM_PORT			4
69 #define F81534_UNUSED_PORT		0xff
70 #define F81534_WRITE_BUFFER_SIZE	512
71 
72 #define DRIVER_DESC			"Fintek F81532/F81534"
73 #define FINTEK_VENDOR_ID_1		0x1934
74 #define FINTEK_VENDOR_ID_2		0x2C42
75 #define FINTEK_DEVICE_ID		0x1202
76 #define F81534_MAX_TX_SIZE		124
77 #define F81534_MAX_RX_SIZE		124
78 #define F81534_RECEIVE_BLOCK_SIZE	128
79 #define F81534_MAX_RECEIVE_BLOCK_SIZE	512
80 
81 #define F81534_TOKEN_RECEIVE		0x01
82 #define F81534_TOKEN_WRITE		0x02
83 #define F81534_TOKEN_TX_EMPTY		0x03
84 #define F81534_TOKEN_MSR_CHANGE		0x04
85 
86 /*
87  * We used interal SPI bus to access FLASH section. We must wait the SPI bus to
88  * idle if we performed any command.
89  *
90  * SPI Bus status register: F81534_BUS_REG_STATUS
91  *	Bit 0/1	: BUSY
92  *	Bit 2	: IDLE
93  */
94 #define F81534_BUS_BUSY			(BIT(0) | BIT(1))
95 #define F81534_BUS_IDLE			BIT(2)
96 #define F81534_BUS_READ_DATA		0x1004
97 #define F81534_BUS_REG_STATUS		0x1003
98 #define F81534_BUS_REG_START		0x1002
99 #define F81534_BUS_REG_END		0x1001
100 
101 #define F81534_CMD_READ			0x03
102 
103 #define F81534_DEFAULT_BAUD_RATE	9600
104 
105 #define F81534_PORT_CONF_RS232		0
106 #define F81534_PORT_CONF_RS485		BIT(0)
107 #define F81534_PORT_CONF_RS485_INVERT	(BIT(0) | BIT(1))
108 #define F81534_PORT_CONF_MODE_MASK	GENMASK(1, 0)
109 #define F81534_PORT_CONF_DISABLE_PORT	BIT(3)
110 #define F81534_PORT_CONF_NOT_EXIST_PORT	BIT(7)
111 #define F81534_PORT_UNAVAILABLE		\
112 	(F81534_PORT_CONF_DISABLE_PORT | F81534_PORT_CONF_NOT_EXIST_PORT)
113 
114 
115 #define F81534_1X_RXTRIGGER		0xc3
116 #define F81534_8X_RXTRIGGER		0xcf
117 
118 /*
119  * F81532/534 Clock registers (offset +08h)
120  *
121  * Bit0:	UART Enable (always on)
122  * Bit2-1:	Clock source selector
123  *			00: 1.846MHz.
124  *			01: 18.46MHz.
125  *			10: 24MHz.
126  *			11: 14.77MHz.
127  * Bit4:	Auto direction(RTS) control (RTS pin Low when TX)
128  * Bit5:	Invert direction(RTS) when Bit4 enabled (RTS pin high when TX)
129  */
130 
131 #define F81534_UART_EN			BIT(0)
132 #define F81534_CLK_1_846_MHZ		0
133 #define F81534_CLK_18_46_MHZ		BIT(1)
134 #define F81534_CLK_24_MHZ		BIT(2)
135 #define F81534_CLK_14_77_MHZ		(BIT(1) | BIT(2))
136 #define F81534_CLK_MASK			GENMASK(2, 1)
137 #define F81534_CLK_TX_DELAY_1BIT	BIT(3)
138 #define F81534_CLK_RS485_MODE		BIT(4)
139 #define F81534_CLK_RS485_INVERT		BIT(5)
140 
141 static const struct usb_device_id f81534_id_table[] = {
142 	{ USB_DEVICE(FINTEK_VENDOR_ID_1, FINTEK_DEVICE_ID) },
143 	{ USB_DEVICE(FINTEK_VENDOR_ID_2, FINTEK_DEVICE_ID) },
144 	{}			/* Terminating entry */
145 };
146 
147 #define F81534_TX_EMPTY_BIT		0
148 
149 struct f81534_serial_private {
150 	u8 conf_data[F81534_DEF_CONF_SIZE];
151 	int tty_idx[F81534_NUM_PORT];
152 	u8 setting_idx;
153 	int opened_port;
154 	struct mutex urb_mutex;
155 };
156 
157 struct f81534_port_private {
158 	struct mutex mcr_mutex;
159 	struct mutex lcr_mutex;
160 	struct work_struct lsr_work;
161 	struct usb_serial_port *port;
162 	unsigned long tx_empty;
163 	spinlock_t msr_lock;
164 	u32 baud_base;
165 	u8 shadow_mcr;
166 	u8 shadow_lcr;
167 	u8 shadow_msr;
168 	u8 shadow_clk;
169 	u8 phy_num;
170 };
171 
172 struct f81534_pin_data {
173 	const u16 reg_addr;
174 	const u8 reg_mask;
175 };
176 
177 struct f81534_port_out_pin {
178 	struct f81534_pin_data pin[3];
179 };
180 
181 /* Pin output value for M2/M1/M0(SD) */
182 static const struct f81534_port_out_pin f81534_port_out_pins[] = {
183 	 { { { 0x2ae8, BIT(7) }, { 0x2a90, BIT(5) }, { 0x2a90, BIT(4) } } },
184 	 { { { 0x2ae8, BIT(6) }, { 0x2ae8, BIT(0) }, { 0x2ae8, BIT(3) } } },
185 	 { { { 0x2a90, BIT(0) }, { 0x2ae8, BIT(2) }, { 0x2a80, BIT(6) } } },
186 	 { { { 0x2a90, BIT(3) }, { 0x2a90, BIT(2) }, { 0x2a90, BIT(1) } } },
187 };
188 
189 static u32 const baudrate_table[] = { 115200, 921600, 1152000, 1500000 };
190 static u8 const clock_table[] = { F81534_CLK_1_846_MHZ, F81534_CLK_14_77_MHZ,
191 				F81534_CLK_18_46_MHZ, F81534_CLK_24_MHZ };
192 
193 static int f81534_logic_to_phy_port(struct usb_serial *serial,
194 					struct usb_serial_port *port)
195 {
196 	struct f81534_serial_private *serial_priv =
197 			usb_get_serial_data(port->serial);
198 	int count = 0;
199 	int i;
200 
201 	for (i = 0; i < F81534_NUM_PORT; ++i) {
202 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
203 			continue;
204 
205 		if (port->port_number == count)
206 			return i;
207 
208 		++count;
209 	}
210 
211 	return -ENODEV;
212 }
213 
214 static int f81534_set_register(struct usb_serial *serial, u16 reg, u8 data)
215 {
216 	struct usb_interface *interface = serial->interface;
217 	struct usb_device *dev = serial->dev;
218 	size_t count = F81534_USB_MAX_RETRY;
219 	int status;
220 	u8 *tmp;
221 
222 	tmp = kmalloc(sizeof(u8), GFP_KERNEL);
223 	if (!tmp)
224 		return -ENOMEM;
225 
226 	*tmp = data;
227 
228 	/*
229 	 * Our device maybe not reply when heavily loading, We'll retry for
230 	 * F81534_USB_MAX_RETRY times.
231 	 */
232 	while (count--) {
233 		status = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
234 					 F81534_SET_GET_REGISTER,
235 					 USB_TYPE_VENDOR | USB_DIR_OUT,
236 					 reg, 0, tmp, sizeof(u8),
237 					 F81534_USB_TIMEOUT);
238 		if (status == sizeof(u8)) {
239 			status = 0;
240 			break;
241 		}
242 	}
243 
244 	if (status < 0) {
245 		dev_err(&interface->dev, "%s: reg: %x data: %x failed: %d\n",
246 				__func__, reg, data, status);
247 	}
248 
249 	kfree(tmp);
250 	return status;
251 }
252 
253 static int f81534_get_register(struct usb_serial *serial, u16 reg, u8 *data)
254 {
255 	struct usb_interface *interface = serial->interface;
256 	struct usb_device *dev = serial->dev;
257 	size_t count = F81534_USB_MAX_RETRY;
258 	int status;
259 	u8 *tmp;
260 
261 	tmp = kmalloc(sizeof(u8), GFP_KERNEL);
262 	if (!tmp)
263 		return -ENOMEM;
264 
265 	/*
266 	 * Our device maybe not reply when heavily loading, We'll retry for
267 	 * F81534_USB_MAX_RETRY times.
268 	 */
269 	while (count--) {
270 		status = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
271 					 F81534_SET_GET_REGISTER,
272 					 USB_TYPE_VENDOR | USB_DIR_IN,
273 					 reg, 0, tmp, sizeof(u8),
274 					 F81534_USB_TIMEOUT);
275 		if (status > 0) {
276 			status = 0;
277 			break;
278 		} else if (status == 0) {
279 			status = -EIO;
280 		}
281 	}
282 
283 	if (status < 0) {
284 		dev_err(&interface->dev, "%s: reg: %x failed: %d\n", __func__,
285 				reg, status);
286 		goto end;
287 	}
288 
289 	*data = *tmp;
290 
291 end:
292 	kfree(tmp);
293 	return status;
294 }
295 
296 static int f81534_set_mask_register(struct usb_serial *serial, u16 reg,
297 					u8 mask, u8 data)
298 {
299 	int status;
300 	u8 tmp;
301 
302 	status = f81534_get_register(serial, reg, &tmp);
303 	if (status)
304 		return status;
305 
306 	tmp &= ~mask;
307 	tmp |= (mask & data);
308 
309 	return f81534_set_register(serial, reg, tmp);
310 }
311 
312 static int f81534_set_phy_port_register(struct usb_serial *serial, int phy,
313 					u16 reg, u8 data)
314 {
315 	return f81534_set_register(serial, reg + F81534_UART_OFFSET * phy,
316 					data);
317 }
318 
319 static int f81534_get_phy_port_register(struct usb_serial *serial, int phy,
320 					u16 reg, u8 *data)
321 {
322 	return f81534_get_register(serial, reg + F81534_UART_OFFSET * phy,
323 					data);
324 }
325 
326 static int f81534_set_port_register(struct usb_serial_port *port, u16 reg,
327 					u8 data)
328 {
329 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
330 
331 	return f81534_set_register(port->serial,
332 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
333 }
334 
335 static int f81534_get_port_register(struct usb_serial_port *port, u16 reg,
336 					u8 *data)
337 {
338 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
339 
340 	return f81534_get_register(port->serial,
341 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
342 }
343 
344 /*
345  * If we try to access the internal flash via SPI bus, we should check the bus
346  * status for every command. e.g., F81534_BUS_REG_START/F81534_BUS_REG_END
347  */
348 static int f81534_wait_for_spi_idle(struct usb_serial *serial)
349 {
350 	size_t count = F81534_MAX_BUS_RETRY;
351 	u8 tmp;
352 	int status;
353 
354 	do {
355 		status = f81534_get_register(serial, F81534_BUS_REG_STATUS,
356 						&tmp);
357 		if (status)
358 			return status;
359 
360 		if (tmp & F81534_BUS_BUSY)
361 			continue;
362 
363 		if (tmp & F81534_BUS_IDLE)
364 			break;
365 
366 	} while (--count);
367 
368 	if (!count) {
369 		dev_err(&serial->interface->dev,
370 				"%s: timed out waiting for idle SPI bus\n",
371 				__func__);
372 		return -EIO;
373 	}
374 
375 	return f81534_set_register(serial, F81534_BUS_REG_STATUS,
376 				tmp & ~F81534_BUS_IDLE);
377 }
378 
379 static int f81534_get_spi_register(struct usb_serial *serial, u16 reg,
380 					u8 *data)
381 {
382 	int status;
383 
384 	status = f81534_get_register(serial, reg, data);
385 	if (status)
386 		return status;
387 
388 	return f81534_wait_for_spi_idle(serial);
389 }
390 
391 static int f81534_set_spi_register(struct usb_serial *serial, u16 reg, u8 data)
392 {
393 	int status;
394 
395 	status = f81534_set_register(serial, reg, data);
396 	if (status)
397 		return status;
398 
399 	return f81534_wait_for_spi_idle(serial);
400 }
401 
402 static int f81534_read_flash(struct usb_serial *serial, u32 address,
403 				size_t size, u8 *buf)
404 {
405 	u8 tmp_buf[F81534_MAX_DATA_BLOCK];
406 	size_t block = 0;
407 	size_t read_size;
408 	size_t count;
409 	int status;
410 	int offset;
411 	u16 reg_tmp;
412 
413 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
414 					F81534_CMD_READ);
415 	if (status)
416 		return status;
417 
418 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
419 					(address >> 16) & 0xff);
420 	if (status)
421 		return status;
422 
423 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
424 					(address >> 8) & 0xff);
425 	if (status)
426 		return status;
427 
428 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
429 					(address >> 0) & 0xff);
430 	if (status)
431 		return status;
432 
433 	/* Continuous read mode */
434 	do {
435 		read_size = min_t(size_t, F81534_MAX_DATA_BLOCK, size);
436 
437 		for (count = 0; count < read_size; ++count) {
438 			/* To write F81534_BUS_REG_END when final byte */
439 			if (size <= F81534_MAX_DATA_BLOCK &&
440 					read_size == count + 1)
441 				reg_tmp = F81534_BUS_REG_END;
442 			else
443 				reg_tmp = F81534_BUS_REG_START;
444 
445 			/*
446 			 * Dummy code, force IC to generate a read pulse, the
447 			 * set of value 0xf1 is dont care (any value is ok)
448 			 */
449 			status = f81534_set_spi_register(serial, reg_tmp,
450 					0xf1);
451 			if (status)
452 				return status;
453 
454 			status = f81534_get_spi_register(serial,
455 						F81534_BUS_READ_DATA,
456 						&tmp_buf[count]);
457 			if (status)
458 				return status;
459 
460 			offset = count + block * F81534_MAX_DATA_BLOCK;
461 			buf[offset] = tmp_buf[count];
462 		}
463 
464 		size -= read_size;
465 		++block;
466 	} while (size);
467 
468 	return 0;
469 }
470 
471 static void f81534_prepare_write_buffer(struct usb_serial_port *port, u8 *buf)
472 {
473 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
474 	int phy_num = port_priv->phy_num;
475 	u8 tx_len;
476 	int i;
477 
478 	/*
479 	 * The block layout is fixed with 4x128 Bytes, per 128 Bytes a port.
480 	 * index 0: port phy idx (e.g., 0,1,2,3)
481 	 * index 1: only F81534_TOKEN_WRITE
482 	 * index 2: serial TX out length
483 	 * index 3: fix to 0
484 	 * index 4~127: serial out data block
485 	 */
486 	for (i = 0; i < F81534_NUM_PORT; ++i) {
487 		buf[i * F81534_RECEIVE_BLOCK_SIZE] = i;
488 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 1] = F81534_TOKEN_WRITE;
489 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 2] = 0;
490 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 3] = 0;
491 	}
492 
493 	tx_len = kfifo_out_locked(&port->write_fifo,
494 				&buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 4],
495 				F81534_MAX_TX_SIZE, &port->lock);
496 
497 	buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 2] = tx_len;
498 }
499 
500 static int f81534_submit_writer(struct usb_serial_port *port, gfp_t mem_flags)
501 {
502 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
503 	struct urb *urb;
504 	unsigned long flags;
505 	int result;
506 
507 	/* Check is any data in write_fifo */
508 	spin_lock_irqsave(&port->lock, flags);
509 
510 	if (kfifo_is_empty(&port->write_fifo)) {
511 		spin_unlock_irqrestore(&port->lock, flags);
512 		return 0;
513 	}
514 
515 	spin_unlock_irqrestore(&port->lock, flags);
516 
517 	/* Check H/W is TXEMPTY */
518 	if (!test_and_clear_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty))
519 		return 0;
520 
521 	urb = port->write_urbs[0];
522 	f81534_prepare_write_buffer(port, port->bulk_out_buffers[0]);
523 	urb->transfer_buffer_length = F81534_WRITE_BUFFER_SIZE;
524 
525 	result = usb_submit_urb(urb, mem_flags);
526 	if (result) {
527 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
528 		dev_err(&port->dev, "%s: submit failed: %d\n", __func__,
529 				result);
530 		return result;
531 	}
532 
533 	usb_serial_port_softint(port);
534 	return 0;
535 }
536 
537 static u32 f81534_calc_baud_divisor(u32 baudrate, u32 clockrate)
538 {
539 	/* Round to nearest divisor */
540 	return DIV_ROUND_CLOSEST(clockrate, baudrate);
541 }
542 
543 static int f81534_find_clk(u32 baudrate)
544 {
545 	int idx;
546 
547 	for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) {
548 		if (baudrate <= baudrate_table[idx] &&
549 				baudrate_table[idx] % baudrate == 0)
550 			return idx;
551 	}
552 
553 	return -EINVAL;
554 }
555 
556 static int f81534_set_port_config(struct usb_serial_port *port,
557 		struct tty_struct *tty, u32 baudrate, u32 old_baudrate, u8 lcr)
558 {
559 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
560 	u32 divisor;
561 	int status;
562 	int i;
563 	int idx;
564 	u8 value;
565 	u32 baud_list[] = {baudrate, old_baudrate, F81534_DEFAULT_BAUD_RATE};
566 
567 	for (i = 0; i < ARRAY_SIZE(baud_list); ++i) {
568 		baudrate = baud_list[i];
569 		if (baudrate == 0) {
570 			tty_encode_baud_rate(tty, 0, 0);
571 			return 0;
572 		}
573 
574 		idx = f81534_find_clk(baudrate);
575 		if (idx >= 0) {
576 			tty_encode_baud_rate(tty, baudrate, baudrate);
577 			break;
578 		}
579 	}
580 
581 	if (idx < 0)
582 		return -EINVAL;
583 
584 	port_priv->baud_base = baudrate_table[idx];
585 	port_priv->shadow_clk &= ~F81534_CLK_MASK;
586 	port_priv->shadow_clk |= clock_table[idx];
587 
588 	status = f81534_set_port_register(port, F81534_CLOCK_REG,
589 			port_priv->shadow_clk);
590 	if (status) {
591 		dev_err(&port->dev, "CLOCK_REG setting failed\n");
592 		return status;
593 	}
594 
595 	if (baudrate <= 1200)
596 		value = F81534_1X_RXTRIGGER;	/* 128 FIFO & TL: 1x */
597 	else
598 		value = F81534_8X_RXTRIGGER;	/* 128 FIFO & TL: 8x */
599 
600 	status = f81534_set_port_register(port, F81534_CONFIG1_REG, value);
601 	if (status) {
602 		dev_err(&port->dev, "%s: CONFIG1 setting failed\n", __func__);
603 		return status;
604 	}
605 
606 	if (baudrate <= 1200)
607 		value = UART_FCR_TRIGGER_1 | UART_FCR_ENABLE_FIFO; /* TL: 1 */
608 	else
609 		value = UART_FCR_TRIGGER_8 | UART_FCR_ENABLE_FIFO; /* TL: 8 */
610 
611 	status = f81534_set_port_register(port, F81534_FIFO_CONTROL_REG,
612 						value);
613 	if (status) {
614 		dev_err(&port->dev, "%s: FCR setting failed\n", __func__);
615 		return status;
616 	}
617 
618 	divisor = f81534_calc_baud_divisor(baudrate, port_priv->baud_base);
619 
620 	mutex_lock(&port_priv->lcr_mutex);
621 
622 	value = UART_LCR_DLAB;
623 	status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG,
624 						value);
625 	if (status) {
626 		dev_err(&port->dev, "%s: set LCR failed\n", __func__);
627 		goto out_unlock;
628 	}
629 
630 	value = divisor & 0xff;
631 	status = f81534_set_port_register(port, F81534_DIVISOR_LSB_REG, value);
632 	if (status) {
633 		dev_err(&port->dev, "%s: set DLAB LSB failed\n", __func__);
634 		goto out_unlock;
635 	}
636 
637 	value = (divisor >> 8) & 0xff;
638 	status = f81534_set_port_register(port, F81534_DIVISOR_MSB_REG, value);
639 	if (status) {
640 		dev_err(&port->dev, "%s: set DLAB MSB failed\n", __func__);
641 		goto out_unlock;
642 	}
643 
644 	value = lcr | (port_priv->shadow_lcr & UART_LCR_SBC);
645 	status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG,
646 						value);
647 	if (status) {
648 		dev_err(&port->dev, "%s: set LCR failed\n", __func__);
649 		goto out_unlock;
650 	}
651 
652 	port_priv->shadow_lcr = value;
653 out_unlock:
654 	mutex_unlock(&port_priv->lcr_mutex);
655 
656 	return status;
657 }
658 
659 static void f81534_break_ctl(struct tty_struct *tty, int break_state)
660 {
661 	struct usb_serial_port *port = tty->driver_data;
662 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
663 	int status;
664 
665 	mutex_lock(&port_priv->lcr_mutex);
666 
667 	if (break_state)
668 		port_priv->shadow_lcr |= UART_LCR_SBC;
669 	else
670 		port_priv->shadow_lcr &= ~UART_LCR_SBC;
671 
672 	status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG,
673 					port_priv->shadow_lcr);
674 	if (status)
675 		dev_err(&port->dev, "set break failed: %d\n", status);
676 
677 	mutex_unlock(&port_priv->lcr_mutex);
678 }
679 
680 static int f81534_update_mctrl(struct usb_serial_port *port, unsigned int set,
681 				unsigned int clear)
682 {
683 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
684 	int status;
685 	u8 tmp;
686 
687 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
688 		return 0;	/* no change */
689 
690 	mutex_lock(&port_priv->mcr_mutex);
691 
692 	/* 'Set' takes precedence over 'Clear' */
693 	clear &= ~set;
694 
695 	/* Always enable UART_MCR_OUT2 */
696 	tmp = UART_MCR_OUT2 | port_priv->shadow_mcr;
697 
698 	if (clear & TIOCM_DTR)
699 		tmp &= ~UART_MCR_DTR;
700 
701 	if (clear & TIOCM_RTS)
702 		tmp &= ~UART_MCR_RTS;
703 
704 	if (set & TIOCM_DTR)
705 		tmp |= UART_MCR_DTR;
706 
707 	if (set & TIOCM_RTS)
708 		tmp |= UART_MCR_RTS;
709 
710 	status = f81534_set_port_register(port, F81534_MODEM_CONTROL_REG, tmp);
711 	if (status < 0) {
712 		dev_err(&port->dev, "%s: MCR write failed\n", __func__);
713 		mutex_unlock(&port_priv->mcr_mutex);
714 		return status;
715 	}
716 
717 	port_priv->shadow_mcr = tmp;
718 	mutex_unlock(&port_priv->mcr_mutex);
719 	return 0;
720 }
721 
722 /*
723  * This function will search the data area with token F81534_CUSTOM_VALID_TOKEN
724  * for latest configuration index. If nothing found
725  * (*index = F81534_CUSTOM_NO_CUSTOM_DATA), We'll load default configure in
726  * F81534_DEF_CONF_ADDRESS_START section.
727  *
728  * Due to we only use block0 to save data, so *index should be 0 or
729  * F81534_CUSTOM_NO_CUSTOM_DATA.
730  */
731 static int f81534_find_config_idx(struct usb_serial *serial, u8 *index)
732 {
733 	u8 tmp;
734 	int status;
735 
736 	status = f81534_read_flash(serial, F81534_CUSTOM_ADDRESS_START, 1,
737 					&tmp);
738 	if (status) {
739 		dev_err(&serial->interface->dev, "%s: read failed: %d\n",
740 				__func__, status);
741 		return status;
742 	}
743 
744 	/* We'll use the custom data when the data is valid. */
745 	if (tmp == F81534_CUSTOM_VALID_TOKEN)
746 		*index = 0;
747 	else
748 		*index = F81534_CUSTOM_NO_CUSTOM_DATA;
749 
750 	return 0;
751 }
752 
753 /*
754  * The F81532/534 will not report serial port to USB serial subsystem when
755  * H/W DCD/DSR/CTS/RI/RX pin connected to ground.
756  *
757  * To detect RX pin status, we'll enable MCR interal loopback, disable it and
758  * delayed for 60ms. It connected to ground If LSR register report UART_LSR_BI.
759  */
760 static bool f81534_check_port_hw_disabled(struct usb_serial *serial, int phy)
761 {
762 	int status;
763 	u8 old_mcr;
764 	u8 msr;
765 	u8 lsr;
766 	u8 msr_mask;
767 
768 	msr_mask = UART_MSR_DCD | UART_MSR_RI | UART_MSR_DSR | UART_MSR_CTS;
769 
770 	status = f81534_get_phy_port_register(serial, phy,
771 				F81534_MODEM_STATUS_REG, &msr);
772 	if (status)
773 		return false;
774 
775 	if ((msr & msr_mask) != msr_mask)
776 		return false;
777 
778 	status = f81534_set_phy_port_register(serial, phy,
779 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
780 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
781 	if (status)
782 		return false;
783 
784 	status = f81534_get_phy_port_register(serial, phy,
785 				F81534_MODEM_CONTROL_REG, &old_mcr);
786 	if (status)
787 		return false;
788 
789 	status = f81534_set_phy_port_register(serial, phy,
790 				F81534_MODEM_CONTROL_REG, UART_MCR_LOOP);
791 	if (status)
792 		return false;
793 
794 	status = f81534_set_phy_port_register(serial, phy,
795 				F81534_MODEM_CONTROL_REG, 0x0);
796 	if (status)
797 		return false;
798 
799 	msleep(60);
800 
801 	status = f81534_get_phy_port_register(serial, phy,
802 				F81534_LINE_STATUS_REG, &lsr);
803 	if (status)
804 		return false;
805 
806 	status = f81534_set_phy_port_register(serial, phy,
807 				F81534_MODEM_CONTROL_REG, old_mcr);
808 	if (status)
809 		return false;
810 
811 	if ((lsr & UART_LSR_BI) == UART_LSR_BI)
812 		return true;
813 
814 	return false;
815 }
816 
817 /*
818  * We had 2 generation of F81532/534 IC. All has an internal storage.
819  *
820  * 1st is pure USB-to-TTL RS232 IC and designed for 4 ports only, no any
821  * internal data will used. All mode and gpio control should manually set
822  * by AP or Driver and all storage space value are 0xff. The
823  * f81534_calc_num_ports() will run to final we marked as "oldest version"
824  * for this IC.
825  *
826  * 2rd is designed to more generic to use any transceiver and this is our
827  * mass production type. We'll save data in F81534_CUSTOM_ADDRESS_START
828  * (0x2f00) with 9bytes. The 1st byte is a indicater. If the token is
829  * F81534_CUSTOM_VALID_TOKEN(0xf0), the IC is 2nd gen type, the following
830  * 4bytes save port mode (0:RS232/1:RS485 Invert/2:RS485), and the last
831  * 4bytes save GPIO state(value from 0~7 to represent 3 GPIO output pin).
832  * The f81534_calc_num_ports() will run to "new style" with checking
833  * F81534_PORT_UNAVAILABLE section.
834  */
835 static int f81534_calc_num_ports(struct usb_serial *serial,
836 					struct usb_serial_endpoints *epds)
837 {
838 	struct f81534_serial_private *serial_priv;
839 	struct device *dev = &serial->interface->dev;
840 	int size_bulk_in = usb_endpoint_maxp(epds->bulk_in[0]);
841 	int size_bulk_out = usb_endpoint_maxp(epds->bulk_out[0]);
842 	u8 num_port = 0;
843 	int index = 0;
844 	int status;
845 	int i;
846 
847 	if (size_bulk_out != F81534_WRITE_BUFFER_SIZE ||
848 			size_bulk_in != F81534_MAX_RECEIVE_BLOCK_SIZE) {
849 		dev_err(dev, "unsupported endpoint max packet size\n");
850 		return -ENODEV;
851 	}
852 
853 	serial_priv = devm_kzalloc(&serial->interface->dev,
854 					sizeof(*serial_priv), GFP_KERNEL);
855 	if (!serial_priv)
856 		return -ENOMEM;
857 
858 	usb_set_serial_data(serial, serial_priv);
859 	mutex_init(&serial_priv->urb_mutex);
860 
861 	/* Check had custom setting */
862 	status = f81534_find_config_idx(serial, &serial_priv->setting_idx);
863 	if (status) {
864 		dev_err(&serial->interface->dev, "%s: find idx failed: %d\n",
865 				__func__, status);
866 		return status;
867 	}
868 
869 	/*
870 	 * We'll read custom data only when data available, otherwise we'll
871 	 * read default value instead.
872 	 */
873 	if (serial_priv->setting_idx != F81534_CUSTOM_NO_CUSTOM_DATA) {
874 		status = f81534_read_flash(serial,
875 						F81534_CUSTOM_ADDRESS_START +
876 						F81534_CONF_OFFSET,
877 						sizeof(serial_priv->conf_data),
878 						serial_priv->conf_data);
879 		if (status) {
880 			dev_err(&serial->interface->dev,
881 					"%s: get custom data failed: %d\n",
882 					__func__, status);
883 			return status;
884 		}
885 
886 		dev_dbg(&serial->interface->dev,
887 				"%s: read config from block: %d\n", __func__,
888 				serial_priv->setting_idx);
889 	} else {
890 		/* Read default board setting */
891 		status = f81534_read_flash(serial,
892 				F81534_DEF_CONF_ADDRESS_START,
893 				sizeof(serial_priv->conf_data),
894 				serial_priv->conf_data);
895 		if (status) {
896 			dev_err(&serial->interface->dev,
897 					"%s: read failed: %d\n", __func__,
898 					status);
899 			return status;
900 		}
901 
902 		dev_dbg(&serial->interface->dev, "%s: read default config\n",
903 				__func__);
904 	}
905 
906 	/* New style, find all possible ports */
907 	for (i = 0; i < F81534_NUM_PORT; ++i) {
908 		if (f81534_check_port_hw_disabled(serial, i))
909 			serial_priv->conf_data[i] |= F81534_PORT_UNAVAILABLE;
910 
911 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
912 			continue;
913 
914 		++num_port;
915 	}
916 
917 	if (!num_port) {
918 		dev_warn(&serial->interface->dev,
919 			"no config found, assuming 4 ports\n");
920 		num_port = 4;		/* Nothing found, oldest version IC */
921 	}
922 
923 	/* Assign phy-to-logic mapping */
924 	for (i = 0; i < F81534_NUM_PORT; ++i) {
925 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
926 			continue;
927 
928 		serial_priv->tty_idx[i] = index++;
929 		dev_dbg(&serial->interface->dev,
930 				"%s: phy_num: %d, tty_idx: %d\n", __func__, i,
931 				serial_priv->tty_idx[i]);
932 	}
933 
934 	/*
935 	 * Setup bulk-out endpoint multiplexing. All ports share the same
936 	 * bulk-out endpoint.
937 	 */
938 	BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < F81534_NUM_PORT);
939 
940 	for (i = 1; i < num_port; ++i)
941 		epds->bulk_out[i] = epds->bulk_out[0];
942 
943 	epds->num_bulk_out = num_port;
944 
945 	return num_port;
946 }
947 
948 static void f81534_set_termios(struct tty_struct *tty,
949 			       struct usb_serial_port *port,
950 			       const struct ktermios *old_termios)
951 {
952 	u8 new_lcr = 0;
953 	int status;
954 	u32 baud;
955 	u32 old_baud;
956 
957 	if (C_BAUD(tty) == B0)
958 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
959 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
960 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
961 
962 	if (C_PARENB(tty)) {
963 		new_lcr |= UART_LCR_PARITY;
964 
965 		if (!C_PARODD(tty))
966 			new_lcr |= UART_LCR_EPAR;
967 
968 		if (C_CMSPAR(tty))
969 			new_lcr |= UART_LCR_SPAR;
970 	}
971 
972 	if (C_CSTOPB(tty))
973 		new_lcr |= UART_LCR_STOP;
974 
975 	new_lcr |= UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
976 
977 	baud = tty_get_baud_rate(tty);
978 	if (!baud)
979 		return;
980 
981 	if (old_termios)
982 		old_baud = tty_termios_baud_rate(old_termios);
983 	else
984 		old_baud = F81534_DEFAULT_BAUD_RATE;
985 
986 	dev_dbg(&port->dev, "%s: baud: %d\n", __func__, baud);
987 
988 	status = f81534_set_port_config(port, tty, baud, old_baud, new_lcr);
989 	if (status < 0) {
990 		dev_err(&port->dev, "%s: set port config failed: %d\n",
991 				__func__, status);
992 	}
993 }
994 
995 static int f81534_submit_read_urb(struct usb_serial *serial, gfp_t flags)
996 {
997 	return usb_serial_generic_submit_read_urbs(serial->port[0], flags);
998 }
999 
1000 static void f81534_msr_changed(struct usb_serial_port *port, u8 msr)
1001 {
1002 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1003 	struct tty_struct *tty;
1004 	unsigned long flags;
1005 	u8 old_msr;
1006 
1007 	if (!(msr & UART_MSR_ANY_DELTA))
1008 		return;
1009 
1010 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1011 	old_msr = port_priv->shadow_msr;
1012 	port_priv->shadow_msr = msr;
1013 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1014 
1015 	dev_dbg(&port->dev, "%s: MSR from %02x to %02x\n", __func__, old_msr,
1016 			msr);
1017 
1018 	/* Update input line counters */
1019 	if (msr & UART_MSR_DCTS)
1020 		port->icount.cts++;
1021 	if (msr & UART_MSR_DDSR)
1022 		port->icount.dsr++;
1023 	if (msr & UART_MSR_DDCD)
1024 		port->icount.dcd++;
1025 	if (msr & UART_MSR_TERI)
1026 		port->icount.rng++;
1027 
1028 	wake_up_interruptible(&port->port.delta_msr_wait);
1029 
1030 	if (!(msr & UART_MSR_DDCD))
1031 		return;
1032 
1033 	dev_dbg(&port->dev, "%s: DCD Changed: phy_num: %d from %x to %x\n",
1034 			__func__, port_priv->phy_num, old_msr, msr);
1035 
1036 	tty = tty_port_tty_get(&port->port);
1037 	if (!tty)
1038 		return;
1039 
1040 	usb_serial_handle_dcd_change(port, tty, msr & UART_MSR_DCD);
1041 	tty_kref_put(tty);
1042 }
1043 
1044 static int f81534_read_msr(struct usb_serial_port *port)
1045 {
1046 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1047 	unsigned long flags;
1048 	int status;
1049 	u8 msr;
1050 
1051 	/* Get MSR initial value */
1052 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1053 	if (status)
1054 		return status;
1055 
1056 	/* Force update current state */
1057 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1058 	port_priv->shadow_msr = msr;
1059 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1060 
1061 	return 0;
1062 }
1063 
1064 static int f81534_open(struct tty_struct *tty, struct usb_serial_port *port)
1065 {
1066 	struct f81534_serial_private *serial_priv =
1067 			usb_get_serial_data(port->serial);
1068 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1069 	int status;
1070 
1071 	status = f81534_set_port_register(port,
1072 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
1073 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
1074 	if (status) {
1075 		dev_err(&port->dev, "%s: Clear FIFO failed: %d\n", __func__,
1076 				status);
1077 		return status;
1078 	}
1079 
1080 	if (tty)
1081 		f81534_set_termios(tty, port, NULL);
1082 
1083 	status = f81534_read_msr(port);
1084 	if (status)
1085 		return status;
1086 
1087 	mutex_lock(&serial_priv->urb_mutex);
1088 
1089 	/* Submit Read URBs for first port opened */
1090 	if (!serial_priv->opened_port) {
1091 		status = f81534_submit_read_urb(port->serial, GFP_KERNEL);
1092 		if (status)
1093 			goto exit;
1094 	}
1095 
1096 	serial_priv->opened_port++;
1097 
1098 exit:
1099 	mutex_unlock(&serial_priv->urb_mutex);
1100 
1101 	set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1102 	return status;
1103 }
1104 
1105 static void f81534_close(struct usb_serial_port *port)
1106 {
1107 	struct f81534_serial_private *serial_priv =
1108 			usb_get_serial_data(port->serial);
1109 	struct usb_serial_port *port0 = port->serial->port[0];
1110 	unsigned long flags;
1111 	size_t i;
1112 
1113 	usb_kill_urb(port->write_urbs[0]);
1114 
1115 	spin_lock_irqsave(&port->lock, flags);
1116 	kfifo_reset_out(&port->write_fifo);
1117 	spin_unlock_irqrestore(&port->lock, flags);
1118 
1119 	/* Kill Read URBs when final port closed */
1120 	mutex_lock(&serial_priv->urb_mutex);
1121 	serial_priv->opened_port--;
1122 
1123 	if (!serial_priv->opened_port) {
1124 		for (i = 0; i < ARRAY_SIZE(port0->read_urbs); ++i)
1125 			usb_kill_urb(port0->read_urbs[i]);
1126 	}
1127 
1128 	mutex_unlock(&serial_priv->urb_mutex);
1129 }
1130 
1131 static void f81534_get_serial_info(struct tty_struct *tty, struct serial_struct *ss)
1132 {
1133 	struct usb_serial_port *port = tty->driver_data;
1134 	struct f81534_port_private *port_priv;
1135 
1136 	port_priv = usb_get_serial_port_data(port);
1137 
1138 	ss->baud_base = port_priv->baud_base;
1139 }
1140 
1141 static void f81534_process_per_serial_block(struct usb_serial_port *port,
1142 		u8 *data)
1143 {
1144 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1145 	int phy_num = data[0];
1146 	size_t read_size = 0;
1147 	size_t i;
1148 	char tty_flag;
1149 	int status;
1150 	u8 lsr;
1151 
1152 	/*
1153 	 * The block layout is 128 Bytes
1154 	 * index 0: port phy idx (e.g., 0,1,2,3),
1155 	 * index 1: It's could be
1156 	 *			F81534_TOKEN_RECEIVE
1157 	 *			F81534_TOKEN_TX_EMPTY
1158 	 *			F81534_TOKEN_MSR_CHANGE
1159 	 * index 2: serial in size (data+lsr, must be even)
1160 	 *			meaningful for F81534_TOKEN_RECEIVE only
1161 	 * index 3: current MSR with this device
1162 	 * index 4~127: serial in data block (data+lsr, must be even)
1163 	 */
1164 	switch (data[1]) {
1165 	case F81534_TOKEN_TX_EMPTY:
1166 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1167 
1168 		/* Try to submit writer */
1169 		status = f81534_submit_writer(port, GFP_ATOMIC);
1170 		if (status)
1171 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1172 		return;
1173 
1174 	case F81534_TOKEN_MSR_CHANGE:
1175 		f81534_msr_changed(port, data[3]);
1176 		return;
1177 
1178 	case F81534_TOKEN_RECEIVE:
1179 		read_size = data[2];
1180 		if (read_size > F81534_MAX_RX_SIZE) {
1181 			dev_err(&port->dev,
1182 				"%s: phy: %d read_size: %zu larger than: %d\n",
1183 				__func__, phy_num, read_size,
1184 				F81534_MAX_RX_SIZE);
1185 			return;
1186 		}
1187 
1188 		break;
1189 
1190 	default:
1191 		dev_warn(&port->dev, "%s: unknown token: %02x\n", __func__,
1192 				data[1]);
1193 		return;
1194 	}
1195 
1196 	for (i = 4; i < 4 + read_size; i += 2) {
1197 		tty_flag = TTY_NORMAL;
1198 		lsr = data[i + 1];
1199 
1200 		if (lsr & UART_LSR_BRK_ERROR_BITS) {
1201 			if (lsr & UART_LSR_BI) {
1202 				tty_flag = TTY_BREAK;
1203 				port->icount.brk++;
1204 				usb_serial_handle_break(port);
1205 			} else if (lsr & UART_LSR_PE) {
1206 				tty_flag = TTY_PARITY;
1207 				port->icount.parity++;
1208 			} else if (lsr & UART_LSR_FE) {
1209 				tty_flag = TTY_FRAME;
1210 				port->icount.frame++;
1211 			}
1212 
1213 			if (lsr & UART_LSR_OE) {
1214 				port->icount.overrun++;
1215 				tty_insert_flip_char(&port->port, 0,
1216 						TTY_OVERRUN);
1217 			}
1218 
1219 			schedule_work(&port_priv->lsr_work);
1220 		}
1221 
1222 		if (port->sysrq) {
1223 			if (usb_serial_handle_sysrq_char(port, data[i]))
1224 				continue;
1225 		}
1226 
1227 		tty_insert_flip_char(&port->port, data[i], tty_flag);
1228 	}
1229 
1230 	tty_flip_buffer_push(&port->port);
1231 }
1232 
1233 static void f81534_process_read_urb(struct urb *urb)
1234 {
1235 	struct f81534_serial_private *serial_priv;
1236 	struct usb_serial_port *port;
1237 	struct usb_serial *serial;
1238 	u8 *buf;
1239 	int phy_port_num;
1240 	int tty_port_num;
1241 	size_t i;
1242 
1243 	if (!urb->actual_length ||
1244 			urb->actual_length % F81534_RECEIVE_BLOCK_SIZE) {
1245 		return;
1246 	}
1247 
1248 	port = urb->context;
1249 	serial = port->serial;
1250 	buf = urb->transfer_buffer;
1251 	serial_priv = usb_get_serial_data(serial);
1252 
1253 	for (i = 0; i < urb->actual_length; i += F81534_RECEIVE_BLOCK_SIZE) {
1254 		phy_port_num = buf[i];
1255 		if (phy_port_num >= F81534_NUM_PORT) {
1256 			dev_err(&port->dev,
1257 				"%s: phy_port_num: %d larger than: %d\n",
1258 				__func__, phy_port_num, F81534_NUM_PORT);
1259 			continue;
1260 		}
1261 
1262 		tty_port_num = serial_priv->tty_idx[phy_port_num];
1263 		port = serial->port[tty_port_num];
1264 
1265 		if (tty_port_initialized(&port->port))
1266 			f81534_process_per_serial_block(port, &buf[i]);
1267 	}
1268 }
1269 
1270 static void f81534_write_usb_callback(struct urb *urb)
1271 {
1272 	struct usb_serial_port *port = urb->context;
1273 
1274 	switch (urb->status) {
1275 	case 0:
1276 		break;
1277 	case -ENOENT:
1278 	case -ECONNRESET:
1279 	case -ESHUTDOWN:
1280 		dev_dbg(&port->dev, "%s - urb stopped: %d\n",
1281 				__func__, urb->status);
1282 		return;
1283 	case -EPIPE:
1284 		dev_err(&port->dev, "%s - urb stopped: %d\n",
1285 				__func__, urb->status);
1286 		return;
1287 	default:
1288 		dev_dbg(&port->dev, "%s - nonzero urb status: %d\n",
1289 				__func__, urb->status);
1290 		break;
1291 	}
1292 }
1293 
1294 static void f81534_lsr_worker(struct work_struct *work)
1295 {
1296 	struct f81534_port_private *port_priv;
1297 	struct usb_serial_port *port;
1298 	int status;
1299 	u8 tmp;
1300 
1301 	port_priv = container_of(work, struct f81534_port_private, lsr_work);
1302 	port = port_priv->port;
1303 
1304 	status = f81534_get_port_register(port, F81534_LINE_STATUS_REG, &tmp);
1305 	if (status)
1306 		dev_warn(&port->dev, "read LSR failed: %d\n", status);
1307 }
1308 
1309 static int f81534_set_port_output_pin(struct usb_serial_port *port)
1310 {
1311 	struct f81534_serial_private *serial_priv;
1312 	struct f81534_port_private *port_priv;
1313 	struct usb_serial *serial;
1314 	const struct f81534_port_out_pin *pins;
1315 	int status;
1316 	int i;
1317 	u8 value;
1318 	u8 idx;
1319 
1320 	serial = port->serial;
1321 	serial_priv = usb_get_serial_data(serial);
1322 	port_priv = usb_get_serial_port_data(port);
1323 
1324 	idx = F81534_CONF_INIT_GPIO_OFFSET + port_priv->phy_num;
1325 	value = serial_priv->conf_data[idx];
1326 	if (value >= F81534_CONF_GPIO_SHUTDOWN) {
1327 		/*
1328 		 * Newer IC configure will make transceiver in shutdown mode on
1329 		 * initial power on. We need enable it before using UARTs.
1330 		 */
1331 		idx = F81534_CONF_WORK_GPIO_OFFSET + port_priv->phy_num;
1332 		value = serial_priv->conf_data[idx];
1333 		if (value >= F81534_CONF_GPIO_SHUTDOWN)
1334 			value = F81534_CONF_GPIO_RS232;
1335 	}
1336 
1337 	pins = &f81534_port_out_pins[port_priv->phy_num];
1338 
1339 	for (i = 0; i < ARRAY_SIZE(pins->pin); ++i) {
1340 		status = f81534_set_mask_register(serial,
1341 				pins->pin[i].reg_addr, pins->pin[i].reg_mask,
1342 				value & BIT(i) ? pins->pin[i].reg_mask : 0);
1343 		if (status)
1344 			return status;
1345 	}
1346 
1347 	dev_dbg(&port->dev, "Output pin (M0/M1/M2): %d\n", value);
1348 	return 0;
1349 }
1350 
1351 static int f81534_port_probe(struct usb_serial_port *port)
1352 {
1353 	struct f81534_serial_private *serial_priv;
1354 	struct f81534_port_private *port_priv;
1355 	int ret;
1356 	u8 value;
1357 
1358 	serial_priv = usb_get_serial_data(port->serial);
1359 	port_priv = devm_kzalloc(&port->dev, sizeof(*port_priv), GFP_KERNEL);
1360 	if (!port_priv)
1361 		return -ENOMEM;
1362 
1363 	/*
1364 	 * We'll make tx frame error when baud rate from 384~500kps. So we'll
1365 	 * delay all tx data frame with 1bit.
1366 	 */
1367 	port_priv->shadow_clk = F81534_UART_EN | F81534_CLK_TX_DELAY_1BIT;
1368 	spin_lock_init(&port_priv->msr_lock);
1369 	mutex_init(&port_priv->mcr_mutex);
1370 	mutex_init(&port_priv->lcr_mutex);
1371 	INIT_WORK(&port_priv->lsr_work, f81534_lsr_worker);
1372 
1373 	/* Assign logic-to-phy mapping */
1374 	ret = f81534_logic_to_phy_port(port->serial, port);
1375 	if (ret < 0)
1376 		return ret;
1377 
1378 	port_priv->phy_num = ret;
1379 	port_priv->port = port;
1380 	usb_set_serial_port_data(port, port_priv);
1381 	dev_dbg(&port->dev, "%s: port_number: %d, phy_num: %d\n", __func__,
1382 			port->port_number, port_priv->phy_num);
1383 
1384 	/*
1385 	 * The F81532/534 will hang-up when enable LSR interrupt in IER and
1386 	 * occur data overrun. So we'll disable the LSR interrupt in probe()
1387 	 * and submit the LSR worker to clear LSR state when reported LSR error
1388 	 * bit with bulk-in data in f81534_process_per_serial_block().
1389 	 */
1390 	ret = f81534_set_port_register(port, F81534_INTERRUPT_ENABLE_REG,
1391 			UART_IER_RDI | UART_IER_THRI | UART_IER_MSI);
1392 	if (ret)
1393 		return ret;
1394 
1395 	value = serial_priv->conf_data[port_priv->phy_num];
1396 	switch (value & F81534_PORT_CONF_MODE_MASK) {
1397 	case F81534_PORT_CONF_RS485_INVERT:
1398 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE |
1399 					F81534_CLK_RS485_INVERT;
1400 		dev_dbg(&port->dev, "RS485 invert mode\n");
1401 		break;
1402 	case F81534_PORT_CONF_RS485:
1403 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE;
1404 		dev_dbg(&port->dev, "RS485 mode\n");
1405 		break;
1406 
1407 	default:
1408 	case F81534_PORT_CONF_RS232:
1409 		dev_dbg(&port->dev, "RS232 mode\n");
1410 		break;
1411 	}
1412 
1413 	return f81534_set_port_output_pin(port);
1414 }
1415 
1416 static void f81534_port_remove(struct usb_serial_port *port)
1417 {
1418 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1419 
1420 	flush_work(&port_priv->lsr_work);
1421 }
1422 
1423 static int f81534_tiocmget(struct tty_struct *tty)
1424 {
1425 	struct usb_serial_port *port = tty->driver_data;
1426 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1427 	int status;
1428 	int r;
1429 	u8 msr;
1430 	u8 mcr;
1431 
1432 	/* Read current MSR from device */
1433 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1434 	if (status)
1435 		return status;
1436 
1437 	mutex_lock(&port_priv->mcr_mutex);
1438 	mcr = port_priv->shadow_mcr;
1439 	mutex_unlock(&port_priv->mcr_mutex);
1440 
1441 	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
1442 	    (mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
1443 	    (msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
1444 	    (msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
1445 	    (msr & UART_MSR_RI ? TIOCM_RI : 0) |
1446 	    (msr & UART_MSR_DSR ? TIOCM_DSR : 0);
1447 
1448 	return r;
1449 }
1450 
1451 static int f81534_tiocmset(struct tty_struct *tty, unsigned int set,
1452 				unsigned int clear)
1453 {
1454 	struct usb_serial_port *port = tty->driver_data;
1455 
1456 	return f81534_update_mctrl(port, set, clear);
1457 }
1458 
1459 static void f81534_dtr_rts(struct usb_serial_port *port, int on)
1460 {
1461 	if (on)
1462 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
1463 	else
1464 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
1465 }
1466 
1467 static int f81534_write(struct tty_struct *tty, struct usb_serial_port *port,
1468 			const u8 *buf, int count)
1469 {
1470 	int bytes_out, status;
1471 
1472 	if (!count)
1473 		return 0;
1474 
1475 	bytes_out = kfifo_in_locked(&port->write_fifo, buf, count,
1476 					&port->lock);
1477 
1478 	status = f81534_submit_writer(port, GFP_ATOMIC);
1479 	if (status) {
1480 		dev_err(&port->dev, "%s: submit failed\n", __func__);
1481 		return status;
1482 	}
1483 
1484 	return bytes_out;
1485 }
1486 
1487 static bool f81534_tx_empty(struct usb_serial_port *port)
1488 {
1489 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1490 
1491 	return test_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1492 }
1493 
1494 static int f81534_resume(struct usb_serial *serial)
1495 {
1496 	struct f81534_serial_private *serial_priv =
1497 			usb_get_serial_data(serial);
1498 	struct usb_serial_port *port;
1499 	int error = 0;
1500 	int status;
1501 	size_t i;
1502 
1503 	/*
1504 	 * We'll register port 0 bulkin when port had opened, It'll take all
1505 	 * port received data, MSR register change and TX_EMPTY information.
1506 	 */
1507 	mutex_lock(&serial_priv->urb_mutex);
1508 
1509 	if (serial_priv->opened_port) {
1510 		status = f81534_submit_read_urb(serial, GFP_NOIO);
1511 		if (status) {
1512 			mutex_unlock(&serial_priv->urb_mutex);
1513 			return status;
1514 		}
1515 	}
1516 
1517 	mutex_unlock(&serial_priv->urb_mutex);
1518 
1519 	for (i = 0; i < serial->num_ports; i++) {
1520 		port = serial->port[i];
1521 		if (!tty_port_initialized(&port->port))
1522 			continue;
1523 
1524 		status = f81534_submit_writer(port, GFP_NOIO);
1525 		if (status) {
1526 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1527 			++error;
1528 		}
1529 	}
1530 
1531 	if (error)
1532 		return -EIO;
1533 
1534 	return 0;
1535 }
1536 
1537 static struct usb_serial_driver f81534_device = {
1538 	.driver = {
1539 		   .owner = THIS_MODULE,
1540 		   .name = "f81534",
1541 	},
1542 	.description =		DRIVER_DESC,
1543 	.id_table =		f81534_id_table,
1544 	.num_bulk_in =		1,
1545 	.num_bulk_out =		1,
1546 	.open =			f81534_open,
1547 	.close =		f81534_close,
1548 	.write =		f81534_write,
1549 	.tx_empty =		f81534_tx_empty,
1550 	.calc_num_ports =	f81534_calc_num_ports,
1551 	.port_probe =		f81534_port_probe,
1552 	.port_remove =		f81534_port_remove,
1553 	.break_ctl =		f81534_break_ctl,
1554 	.dtr_rts =		f81534_dtr_rts,
1555 	.process_read_urb =	f81534_process_read_urb,
1556 	.get_serial =		f81534_get_serial_info,
1557 	.tiocmget =		f81534_tiocmget,
1558 	.tiocmset =		f81534_tiocmset,
1559 	.write_bulk_callback =	f81534_write_usb_callback,
1560 	.set_termios =		f81534_set_termios,
1561 	.resume =		f81534_resume,
1562 };
1563 
1564 static struct usb_serial_driver *const serial_drivers[] = {
1565 	&f81534_device, NULL
1566 };
1567 
1568 module_usb_serial_driver(serial_drivers, f81534_id_table);
1569 
1570 MODULE_DEVICE_TABLE(usb, f81534_id_table);
1571 MODULE_DESCRIPTION(DRIVER_DESC);
1572 MODULE_AUTHOR("Peter Hong <Peter_Hong@fintek.com.tw>");
1573 MODULE_AUTHOR("Tom Tsai <Tom_Tsai@fintek.com.tw>");
1574 MODULE_LICENSE("GPL");
1575