xref: /openbmc/linux/drivers/usb/serial/f81534.c (revision 20e2fc42)
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 > 0) {
239 			status = 0;
240 			break;
241 		} else if (status == 0) {
242 			status = -EIO;
243 		}
244 	}
245 
246 	if (status < 0) {
247 		dev_err(&interface->dev, "%s: reg: %x data: %x failed: %d\n",
248 				__func__, reg, data, status);
249 	}
250 
251 	kfree(tmp);
252 	return status;
253 }
254 
255 static int f81534_get_register(struct usb_serial *serial, u16 reg, u8 *data)
256 {
257 	struct usb_interface *interface = serial->interface;
258 	struct usb_device *dev = serial->dev;
259 	size_t count = F81534_USB_MAX_RETRY;
260 	int status;
261 	u8 *tmp;
262 
263 	tmp = kmalloc(sizeof(u8), GFP_KERNEL);
264 	if (!tmp)
265 		return -ENOMEM;
266 
267 	/*
268 	 * Our device maybe not reply when heavily loading, We'll retry for
269 	 * F81534_USB_MAX_RETRY times.
270 	 */
271 	while (count--) {
272 		status = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
273 					 F81534_SET_GET_REGISTER,
274 					 USB_TYPE_VENDOR | USB_DIR_IN,
275 					 reg, 0, tmp, sizeof(u8),
276 					 F81534_USB_TIMEOUT);
277 		if (status > 0) {
278 			status = 0;
279 			break;
280 		} else if (status == 0) {
281 			status = -EIO;
282 		}
283 	}
284 
285 	if (status < 0) {
286 		dev_err(&interface->dev, "%s: reg: %x failed: %d\n", __func__,
287 				reg, status);
288 		goto end;
289 	}
290 
291 	*data = *tmp;
292 
293 end:
294 	kfree(tmp);
295 	return status;
296 }
297 
298 static int f81534_set_mask_register(struct usb_serial *serial, u16 reg,
299 					u8 mask, u8 data)
300 {
301 	int status;
302 	u8 tmp;
303 
304 	status = f81534_get_register(serial, reg, &tmp);
305 	if (status)
306 		return status;
307 
308 	tmp &= ~mask;
309 	tmp |= (mask & data);
310 
311 	return f81534_set_register(serial, reg, tmp);
312 }
313 
314 static int f81534_set_phy_port_register(struct usb_serial *serial, int phy,
315 					u16 reg, u8 data)
316 {
317 	return f81534_set_register(serial, reg + F81534_UART_OFFSET * phy,
318 					data);
319 }
320 
321 static int f81534_get_phy_port_register(struct usb_serial *serial, int phy,
322 					u16 reg, u8 *data)
323 {
324 	return f81534_get_register(serial, reg + F81534_UART_OFFSET * phy,
325 					data);
326 }
327 
328 static int f81534_set_port_register(struct usb_serial_port *port, u16 reg,
329 					u8 data)
330 {
331 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
332 
333 	return f81534_set_register(port->serial,
334 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
335 }
336 
337 static int f81534_get_port_register(struct usb_serial_port *port, u16 reg,
338 					u8 *data)
339 {
340 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
341 
342 	return f81534_get_register(port->serial,
343 			reg + port_priv->phy_num * F81534_UART_OFFSET, data);
344 }
345 
346 /*
347  * If we try to access the internal flash via SPI bus, we should check the bus
348  * status for every command. e.g., F81534_BUS_REG_START/F81534_BUS_REG_END
349  */
350 static int f81534_wait_for_spi_idle(struct usb_serial *serial)
351 {
352 	size_t count = F81534_MAX_BUS_RETRY;
353 	u8 tmp;
354 	int status;
355 
356 	do {
357 		status = f81534_get_register(serial, F81534_BUS_REG_STATUS,
358 						&tmp);
359 		if (status)
360 			return status;
361 
362 		if (tmp & F81534_BUS_BUSY)
363 			continue;
364 
365 		if (tmp & F81534_BUS_IDLE)
366 			break;
367 
368 	} while (--count);
369 
370 	if (!count) {
371 		dev_err(&serial->interface->dev,
372 				"%s: timed out waiting for idle SPI bus\n",
373 				__func__);
374 		return -EIO;
375 	}
376 
377 	return f81534_set_register(serial, F81534_BUS_REG_STATUS,
378 				tmp & ~F81534_BUS_IDLE);
379 }
380 
381 static int f81534_get_spi_register(struct usb_serial *serial, u16 reg,
382 					u8 *data)
383 {
384 	int status;
385 
386 	status = f81534_get_register(serial, reg, data);
387 	if (status)
388 		return status;
389 
390 	return f81534_wait_for_spi_idle(serial);
391 }
392 
393 static int f81534_set_spi_register(struct usb_serial *serial, u16 reg, u8 data)
394 {
395 	int status;
396 
397 	status = f81534_set_register(serial, reg, data);
398 	if (status)
399 		return status;
400 
401 	return f81534_wait_for_spi_idle(serial);
402 }
403 
404 static int f81534_read_flash(struct usb_serial *serial, u32 address,
405 				size_t size, u8 *buf)
406 {
407 	u8 tmp_buf[F81534_MAX_DATA_BLOCK];
408 	size_t block = 0;
409 	size_t read_size;
410 	size_t count;
411 	int status;
412 	int offset;
413 	u16 reg_tmp;
414 
415 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
416 					F81534_CMD_READ);
417 	if (status)
418 		return status;
419 
420 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
421 					(address >> 16) & 0xff);
422 	if (status)
423 		return status;
424 
425 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
426 					(address >> 8) & 0xff);
427 	if (status)
428 		return status;
429 
430 	status = f81534_set_spi_register(serial, F81534_BUS_REG_START,
431 					(address >> 0) & 0xff);
432 	if (status)
433 		return status;
434 
435 	/* Continuous read mode */
436 	do {
437 		read_size = min_t(size_t, F81534_MAX_DATA_BLOCK, size);
438 
439 		for (count = 0; count < read_size; ++count) {
440 			/* To write F81534_BUS_REG_END when final byte */
441 			if (size <= F81534_MAX_DATA_BLOCK &&
442 					read_size == count + 1)
443 				reg_tmp = F81534_BUS_REG_END;
444 			else
445 				reg_tmp = F81534_BUS_REG_START;
446 
447 			/*
448 			 * Dummy code, force IC to generate a read pulse, the
449 			 * set of value 0xf1 is dont care (any value is ok)
450 			 */
451 			status = f81534_set_spi_register(serial, reg_tmp,
452 					0xf1);
453 			if (status)
454 				return status;
455 
456 			status = f81534_get_spi_register(serial,
457 						F81534_BUS_READ_DATA,
458 						&tmp_buf[count]);
459 			if (status)
460 				return status;
461 
462 			offset = count + block * F81534_MAX_DATA_BLOCK;
463 			buf[offset] = tmp_buf[count];
464 		}
465 
466 		size -= read_size;
467 		++block;
468 	} while (size);
469 
470 	return 0;
471 }
472 
473 static void f81534_prepare_write_buffer(struct usb_serial_port *port, u8 *buf)
474 {
475 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
476 	int phy_num = port_priv->phy_num;
477 	u8 tx_len;
478 	int i;
479 
480 	/*
481 	 * The block layout is fixed with 4x128 Bytes, per 128 Bytes a port.
482 	 * index 0: port phy idx (e.g., 0,1,2,3)
483 	 * index 1: only F81534_TOKEN_WRITE
484 	 * index 2: serial TX out length
485 	 * index 3: fix to 0
486 	 * index 4~127: serial out data block
487 	 */
488 	for (i = 0; i < F81534_NUM_PORT; ++i) {
489 		buf[i * F81534_RECEIVE_BLOCK_SIZE] = i;
490 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 1] = F81534_TOKEN_WRITE;
491 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 2] = 0;
492 		buf[i * F81534_RECEIVE_BLOCK_SIZE + 3] = 0;
493 	}
494 
495 	tx_len = kfifo_out_locked(&port->write_fifo,
496 				&buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 4],
497 				F81534_MAX_TX_SIZE, &port->lock);
498 
499 	buf[phy_num * F81534_RECEIVE_BLOCK_SIZE + 2] = tx_len;
500 }
501 
502 static int f81534_submit_writer(struct usb_serial_port *port, gfp_t mem_flags)
503 {
504 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
505 	struct urb *urb;
506 	unsigned long flags;
507 	int result;
508 
509 	/* Check is any data in write_fifo */
510 	spin_lock_irqsave(&port->lock, flags);
511 
512 	if (kfifo_is_empty(&port->write_fifo)) {
513 		spin_unlock_irqrestore(&port->lock, flags);
514 		return 0;
515 	}
516 
517 	spin_unlock_irqrestore(&port->lock, flags);
518 
519 	/* Check H/W is TXEMPTY */
520 	if (!test_and_clear_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty))
521 		return 0;
522 
523 	urb = port->write_urbs[0];
524 	f81534_prepare_write_buffer(port, port->bulk_out_buffers[0]);
525 	urb->transfer_buffer_length = F81534_WRITE_BUFFER_SIZE;
526 
527 	result = usb_submit_urb(urb, mem_flags);
528 	if (result) {
529 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
530 		dev_err(&port->dev, "%s: submit failed: %d\n", __func__,
531 				result);
532 		return result;
533 	}
534 
535 	usb_serial_port_softint(port);
536 	return 0;
537 }
538 
539 static u32 f81534_calc_baud_divisor(u32 baudrate, u32 clockrate)
540 {
541 	if (!baudrate)
542 		return 0;
543 
544 	/* Round to nearest divisor */
545 	return DIV_ROUND_CLOSEST(clockrate, baudrate);
546 }
547 
548 static int f81534_find_clk(u32 baudrate)
549 {
550 	int idx;
551 
552 	for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) {
553 		if (baudrate <= baudrate_table[idx] &&
554 				baudrate_table[idx] % baudrate == 0)
555 			return idx;
556 	}
557 
558 	return -EINVAL;
559 }
560 
561 static int f81534_set_port_config(struct usb_serial_port *port,
562 		struct tty_struct *tty, u32 baudrate, u32 old_baudrate, u8 lcr)
563 {
564 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
565 	u32 divisor;
566 	int status;
567 	int i;
568 	int idx;
569 	u8 value;
570 	u32 baud_list[] = {baudrate, old_baudrate, F81534_DEFAULT_BAUD_RATE};
571 
572 	for (i = 0; i < ARRAY_SIZE(baud_list); ++i) {
573 		idx = f81534_find_clk(baud_list[i]);
574 		if (idx >= 0) {
575 			baudrate = baud_list[i];
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 				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 	switch (C_CSIZE(tty)) {
976 	case CS5:
977 		new_lcr |= UART_LCR_WLEN5;
978 		break;
979 	case CS6:
980 		new_lcr |= UART_LCR_WLEN6;
981 		break;
982 	case CS7:
983 		new_lcr |= UART_LCR_WLEN7;
984 		break;
985 	default:
986 	case CS8:
987 		new_lcr |= UART_LCR_WLEN8;
988 		break;
989 	}
990 
991 	baud = tty_get_baud_rate(tty);
992 	if (!baud)
993 		return;
994 
995 	if (old_termios)
996 		old_baud = tty_termios_baud_rate(old_termios);
997 	else
998 		old_baud = F81534_DEFAULT_BAUD_RATE;
999 
1000 	dev_dbg(&port->dev, "%s: baud: %d\n", __func__, baud);
1001 
1002 	status = f81534_set_port_config(port, tty, baud, old_baud, new_lcr);
1003 	if (status < 0) {
1004 		dev_err(&port->dev, "%s: set port config failed: %d\n",
1005 				__func__, status);
1006 	}
1007 }
1008 
1009 static int f81534_submit_read_urb(struct usb_serial *serial, gfp_t flags)
1010 {
1011 	return usb_serial_generic_submit_read_urbs(serial->port[0], flags);
1012 }
1013 
1014 static void f81534_msr_changed(struct usb_serial_port *port, u8 msr)
1015 {
1016 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1017 	struct tty_struct *tty;
1018 	unsigned long flags;
1019 	u8 old_msr;
1020 
1021 	if (!(msr & UART_MSR_ANY_DELTA))
1022 		return;
1023 
1024 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1025 	old_msr = port_priv->shadow_msr;
1026 	port_priv->shadow_msr = msr;
1027 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1028 
1029 	dev_dbg(&port->dev, "%s: MSR from %02x to %02x\n", __func__, old_msr,
1030 			msr);
1031 
1032 	/* Update input line counters */
1033 	if (msr & UART_MSR_DCTS)
1034 		port->icount.cts++;
1035 	if (msr & UART_MSR_DDSR)
1036 		port->icount.dsr++;
1037 	if (msr & UART_MSR_DDCD)
1038 		port->icount.dcd++;
1039 	if (msr & UART_MSR_TERI)
1040 		port->icount.rng++;
1041 
1042 	wake_up_interruptible(&port->port.delta_msr_wait);
1043 
1044 	if (!(msr & UART_MSR_DDCD))
1045 		return;
1046 
1047 	dev_dbg(&port->dev, "%s: DCD Changed: phy_num: %d from %x to %x\n",
1048 			__func__, port_priv->phy_num, old_msr, msr);
1049 
1050 	tty = tty_port_tty_get(&port->port);
1051 	if (!tty)
1052 		return;
1053 
1054 	usb_serial_handle_dcd_change(port, tty, msr & UART_MSR_DCD);
1055 	tty_kref_put(tty);
1056 }
1057 
1058 static int f81534_read_msr(struct usb_serial_port *port)
1059 {
1060 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1061 	unsigned long flags;
1062 	int status;
1063 	u8 msr;
1064 
1065 	/* Get MSR initial value */
1066 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1067 	if (status)
1068 		return status;
1069 
1070 	/* Force update current state */
1071 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1072 	port_priv->shadow_msr = msr;
1073 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1074 
1075 	return 0;
1076 }
1077 
1078 static int f81534_open(struct tty_struct *tty, struct usb_serial_port *port)
1079 {
1080 	struct f81534_serial_private *serial_priv =
1081 			usb_get_serial_data(port->serial);
1082 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1083 	int status;
1084 
1085 	status = f81534_set_port_register(port,
1086 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
1087 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
1088 	if (status) {
1089 		dev_err(&port->dev, "%s: Clear FIFO failed: %d\n", __func__,
1090 				status);
1091 		return status;
1092 	}
1093 
1094 	if (tty)
1095 		f81534_set_termios(tty, port, NULL);
1096 
1097 	status = f81534_read_msr(port);
1098 	if (status)
1099 		return status;
1100 
1101 	mutex_lock(&serial_priv->urb_mutex);
1102 
1103 	/* Submit Read URBs for first port opened */
1104 	if (!serial_priv->opened_port) {
1105 		status = f81534_submit_read_urb(port->serial, GFP_KERNEL);
1106 		if (status)
1107 			goto exit;
1108 	}
1109 
1110 	serial_priv->opened_port++;
1111 
1112 exit:
1113 	mutex_unlock(&serial_priv->urb_mutex);
1114 
1115 	set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1116 	return status;
1117 }
1118 
1119 static void f81534_close(struct usb_serial_port *port)
1120 {
1121 	struct f81534_serial_private *serial_priv =
1122 			usb_get_serial_data(port->serial);
1123 	struct usb_serial_port *port0 = port->serial->port[0];
1124 	unsigned long flags;
1125 	size_t i;
1126 
1127 	usb_kill_urb(port->write_urbs[0]);
1128 
1129 	spin_lock_irqsave(&port->lock, flags);
1130 	kfifo_reset_out(&port->write_fifo);
1131 	spin_unlock_irqrestore(&port->lock, flags);
1132 
1133 	/* Kill Read URBs when final port closed */
1134 	mutex_lock(&serial_priv->urb_mutex);
1135 	serial_priv->opened_port--;
1136 
1137 	if (!serial_priv->opened_port) {
1138 		for (i = 0; i < ARRAY_SIZE(port0->read_urbs); ++i)
1139 			usb_kill_urb(port0->read_urbs[i]);
1140 	}
1141 
1142 	mutex_unlock(&serial_priv->urb_mutex);
1143 }
1144 
1145 static int f81534_get_serial_info(struct tty_struct *tty,
1146 				  struct serial_struct *ss)
1147 {
1148 	struct usb_serial_port *port = tty->driver_data;
1149 	struct f81534_port_private *port_priv;
1150 
1151 	port_priv = usb_get_serial_port_data(port);
1152 
1153 	ss->type = PORT_16550A;
1154 	ss->port = port->port_number;
1155 	ss->line = port->minor;
1156 	ss->baud_base = port_priv->baud_base;
1157 	return 0;
1158 }
1159 
1160 static void f81534_process_per_serial_block(struct usb_serial_port *port,
1161 		u8 *data)
1162 {
1163 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1164 	int phy_num = data[0];
1165 	size_t read_size = 0;
1166 	size_t i;
1167 	char tty_flag;
1168 	int status;
1169 	u8 lsr;
1170 
1171 	/*
1172 	 * The block layout is 128 Bytes
1173 	 * index 0: port phy idx (e.g., 0,1,2,3),
1174 	 * index 1: It's could be
1175 	 *			F81534_TOKEN_RECEIVE
1176 	 *			F81534_TOKEN_TX_EMPTY
1177 	 *			F81534_TOKEN_MSR_CHANGE
1178 	 * index 2: serial in size (data+lsr, must be even)
1179 	 *			meaningful for F81534_TOKEN_RECEIVE only
1180 	 * index 3: current MSR with this device
1181 	 * index 4~127: serial in data block (data+lsr, must be even)
1182 	 */
1183 	switch (data[1]) {
1184 	case F81534_TOKEN_TX_EMPTY:
1185 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1186 
1187 		/* Try to submit writer */
1188 		status = f81534_submit_writer(port, GFP_ATOMIC);
1189 		if (status)
1190 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1191 		return;
1192 
1193 	case F81534_TOKEN_MSR_CHANGE:
1194 		f81534_msr_changed(port, data[3]);
1195 		return;
1196 
1197 	case F81534_TOKEN_RECEIVE:
1198 		read_size = data[2];
1199 		if (read_size > F81534_MAX_RX_SIZE) {
1200 			dev_err(&port->dev,
1201 				"%s: phy: %d read_size: %zu larger than: %d\n",
1202 				__func__, phy_num, read_size,
1203 				F81534_MAX_RX_SIZE);
1204 			return;
1205 		}
1206 
1207 		break;
1208 
1209 	default:
1210 		dev_warn(&port->dev, "%s: unknown token: %02x\n", __func__,
1211 				data[1]);
1212 		return;
1213 	}
1214 
1215 	for (i = 4; i < 4 + read_size; i += 2) {
1216 		tty_flag = TTY_NORMAL;
1217 		lsr = data[i + 1];
1218 
1219 		if (lsr & UART_LSR_BRK_ERROR_BITS) {
1220 			if (lsr & UART_LSR_BI) {
1221 				tty_flag = TTY_BREAK;
1222 				port->icount.brk++;
1223 				usb_serial_handle_break(port);
1224 			} else if (lsr & UART_LSR_PE) {
1225 				tty_flag = TTY_PARITY;
1226 				port->icount.parity++;
1227 			} else if (lsr & UART_LSR_FE) {
1228 				tty_flag = TTY_FRAME;
1229 				port->icount.frame++;
1230 			}
1231 
1232 			if (lsr & UART_LSR_OE) {
1233 				port->icount.overrun++;
1234 				tty_insert_flip_char(&port->port, 0,
1235 						TTY_OVERRUN);
1236 			}
1237 
1238 			schedule_work(&port_priv->lsr_work);
1239 		}
1240 
1241 		if (port->port.console && port->sysrq) {
1242 			if (usb_serial_handle_sysrq_char(port, data[i]))
1243 				continue;
1244 		}
1245 
1246 		tty_insert_flip_char(&port->port, data[i], tty_flag);
1247 	}
1248 
1249 	tty_flip_buffer_push(&port->port);
1250 }
1251 
1252 static void f81534_process_read_urb(struct urb *urb)
1253 {
1254 	struct f81534_serial_private *serial_priv;
1255 	struct usb_serial_port *port;
1256 	struct usb_serial *serial;
1257 	u8 *buf;
1258 	int phy_port_num;
1259 	int tty_port_num;
1260 	size_t i;
1261 
1262 	if (!urb->actual_length ||
1263 			urb->actual_length % F81534_RECEIVE_BLOCK_SIZE) {
1264 		return;
1265 	}
1266 
1267 	port = urb->context;
1268 	serial = port->serial;
1269 	buf = urb->transfer_buffer;
1270 	serial_priv = usb_get_serial_data(serial);
1271 
1272 	for (i = 0; i < urb->actual_length; i += F81534_RECEIVE_BLOCK_SIZE) {
1273 		phy_port_num = buf[i];
1274 		if (phy_port_num >= F81534_NUM_PORT) {
1275 			dev_err(&port->dev,
1276 				"%s: phy_port_num: %d larger than: %d\n",
1277 				__func__, phy_port_num, F81534_NUM_PORT);
1278 			continue;
1279 		}
1280 
1281 		tty_port_num = serial_priv->tty_idx[phy_port_num];
1282 		port = serial->port[tty_port_num];
1283 
1284 		if (tty_port_initialized(&port->port))
1285 			f81534_process_per_serial_block(port, &buf[i]);
1286 	}
1287 }
1288 
1289 static void f81534_write_usb_callback(struct urb *urb)
1290 {
1291 	struct usb_serial_port *port = urb->context;
1292 
1293 	switch (urb->status) {
1294 	case 0:
1295 		break;
1296 	case -ENOENT:
1297 	case -ECONNRESET:
1298 	case -ESHUTDOWN:
1299 		dev_dbg(&port->dev, "%s - urb stopped: %d\n",
1300 				__func__, urb->status);
1301 		return;
1302 	case -EPIPE:
1303 		dev_err(&port->dev, "%s - urb stopped: %d\n",
1304 				__func__, urb->status);
1305 		return;
1306 	default:
1307 		dev_dbg(&port->dev, "%s - nonzero urb status: %d\n",
1308 				__func__, urb->status);
1309 		break;
1310 	}
1311 }
1312 
1313 static void f81534_lsr_worker(struct work_struct *work)
1314 {
1315 	struct f81534_port_private *port_priv;
1316 	struct usb_serial_port *port;
1317 	int status;
1318 	u8 tmp;
1319 
1320 	port_priv = container_of(work, struct f81534_port_private, lsr_work);
1321 	port = port_priv->port;
1322 
1323 	status = f81534_get_port_register(port, F81534_LINE_STATUS_REG, &tmp);
1324 	if (status)
1325 		dev_warn(&port->dev, "read LSR failed: %d\n", status);
1326 }
1327 
1328 static int f81534_set_port_output_pin(struct usb_serial_port *port)
1329 {
1330 	struct f81534_serial_private *serial_priv;
1331 	struct f81534_port_private *port_priv;
1332 	struct usb_serial *serial;
1333 	const struct f81534_port_out_pin *pins;
1334 	int status;
1335 	int i;
1336 	u8 value;
1337 	u8 idx;
1338 
1339 	serial = port->serial;
1340 	serial_priv = usb_get_serial_data(serial);
1341 	port_priv = usb_get_serial_port_data(port);
1342 
1343 	idx = F81534_CONF_INIT_GPIO_OFFSET + port_priv->phy_num;
1344 	value = serial_priv->conf_data[idx];
1345 	if (value >= F81534_CONF_GPIO_SHUTDOWN) {
1346 		/*
1347 		 * Newer IC configure will make transceiver in shutdown mode on
1348 		 * initial power on. We need enable it before using UARTs.
1349 		 */
1350 		idx = F81534_CONF_WORK_GPIO_OFFSET + port_priv->phy_num;
1351 		value = serial_priv->conf_data[idx];
1352 		if (value >= F81534_CONF_GPIO_SHUTDOWN)
1353 			value = F81534_CONF_GPIO_RS232;
1354 	}
1355 
1356 	pins = &f81534_port_out_pins[port_priv->phy_num];
1357 
1358 	for (i = 0; i < ARRAY_SIZE(pins->pin); ++i) {
1359 		status = f81534_set_mask_register(serial,
1360 				pins->pin[i].reg_addr, pins->pin[i].reg_mask,
1361 				value & BIT(i) ? pins->pin[i].reg_mask : 0);
1362 		if (status)
1363 			return status;
1364 	}
1365 
1366 	dev_dbg(&port->dev, "Output pin (M0/M1/M2): %d\n", value);
1367 	return 0;
1368 }
1369 
1370 static int f81534_port_probe(struct usb_serial_port *port)
1371 {
1372 	struct f81534_serial_private *serial_priv;
1373 	struct f81534_port_private *port_priv;
1374 	int ret;
1375 	u8 value;
1376 
1377 	serial_priv = usb_get_serial_data(port->serial);
1378 	port_priv = devm_kzalloc(&port->dev, sizeof(*port_priv), GFP_KERNEL);
1379 	if (!port_priv)
1380 		return -ENOMEM;
1381 
1382 	/*
1383 	 * We'll make tx frame error when baud rate from 384~500kps. So we'll
1384 	 * delay all tx data frame with 1bit.
1385 	 */
1386 	port_priv->shadow_clk = F81534_UART_EN | F81534_CLK_TX_DELAY_1BIT;
1387 	spin_lock_init(&port_priv->msr_lock);
1388 	mutex_init(&port_priv->mcr_mutex);
1389 	mutex_init(&port_priv->lcr_mutex);
1390 	INIT_WORK(&port_priv->lsr_work, f81534_lsr_worker);
1391 
1392 	/* Assign logic-to-phy mapping */
1393 	ret = f81534_logic_to_phy_port(port->serial, port);
1394 	if (ret < 0)
1395 		return ret;
1396 
1397 	port_priv->phy_num = ret;
1398 	port_priv->port = port;
1399 	usb_set_serial_port_data(port, port_priv);
1400 	dev_dbg(&port->dev, "%s: port_number: %d, phy_num: %d\n", __func__,
1401 			port->port_number, port_priv->phy_num);
1402 
1403 	/*
1404 	 * The F81532/534 will hang-up when enable LSR interrupt in IER and
1405 	 * occur data overrun. So we'll disable the LSR interrupt in probe()
1406 	 * and submit the LSR worker to clear LSR state when reported LSR error
1407 	 * bit with bulk-in data in f81534_process_per_serial_block().
1408 	 */
1409 	ret = f81534_set_port_register(port, F81534_INTERRUPT_ENABLE_REG,
1410 			UART_IER_RDI | UART_IER_THRI | UART_IER_MSI);
1411 	if (ret)
1412 		return ret;
1413 
1414 	value = serial_priv->conf_data[port_priv->phy_num];
1415 	switch (value & F81534_PORT_CONF_MODE_MASK) {
1416 	case F81534_PORT_CONF_RS485_INVERT:
1417 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE |
1418 					F81534_CLK_RS485_INVERT;
1419 		dev_dbg(&port->dev, "RS485 invert mode\n");
1420 		break;
1421 	case F81534_PORT_CONF_RS485:
1422 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE;
1423 		dev_dbg(&port->dev, "RS485 mode\n");
1424 		break;
1425 
1426 	default:
1427 	case F81534_PORT_CONF_RS232:
1428 		dev_dbg(&port->dev, "RS232 mode\n");
1429 		break;
1430 	}
1431 
1432 	return f81534_set_port_output_pin(port);
1433 }
1434 
1435 static int f81534_port_remove(struct usb_serial_port *port)
1436 {
1437 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1438 
1439 	flush_work(&port_priv->lsr_work);
1440 	return 0;
1441 }
1442 
1443 static int f81534_tiocmget(struct tty_struct *tty)
1444 {
1445 	struct usb_serial_port *port = tty->driver_data;
1446 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1447 	int status;
1448 	int r;
1449 	u8 msr;
1450 	u8 mcr;
1451 
1452 	/* Read current MSR from device */
1453 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1454 	if (status)
1455 		return status;
1456 
1457 	mutex_lock(&port_priv->mcr_mutex);
1458 	mcr = port_priv->shadow_mcr;
1459 	mutex_unlock(&port_priv->mcr_mutex);
1460 
1461 	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
1462 	    (mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
1463 	    (msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
1464 	    (msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
1465 	    (msr & UART_MSR_RI ? TIOCM_RI : 0) |
1466 	    (msr & UART_MSR_DSR ? TIOCM_DSR : 0);
1467 
1468 	return r;
1469 }
1470 
1471 static int f81534_tiocmset(struct tty_struct *tty, unsigned int set,
1472 				unsigned int clear)
1473 {
1474 	struct usb_serial_port *port = tty->driver_data;
1475 
1476 	return f81534_update_mctrl(port, set, clear);
1477 }
1478 
1479 static void f81534_dtr_rts(struct usb_serial_port *port, int on)
1480 {
1481 	if (on)
1482 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
1483 	else
1484 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
1485 }
1486 
1487 static int f81534_write(struct tty_struct *tty, struct usb_serial_port *port,
1488 			const u8 *buf, int count)
1489 {
1490 	int bytes_out, status;
1491 
1492 	if (!count)
1493 		return 0;
1494 
1495 	bytes_out = kfifo_in_locked(&port->write_fifo, buf, count,
1496 					&port->lock);
1497 
1498 	status = f81534_submit_writer(port, GFP_ATOMIC);
1499 	if (status) {
1500 		dev_err(&port->dev, "%s: submit failed\n", __func__);
1501 		return status;
1502 	}
1503 
1504 	return bytes_out;
1505 }
1506 
1507 static bool f81534_tx_empty(struct usb_serial_port *port)
1508 {
1509 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1510 
1511 	return test_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1512 }
1513 
1514 static int f81534_resume(struct usb_serial *serial)
1515 {
1516 	struct f81534_serial_private *serial_priv =
1517 			usb_get_serial_data(serial);
1518 	struct usb_serial_port *port;
1519 	int error = 0;
1520 	int status;
1521 	size_t i;
1522 
1523 	/*
1524 	 * We'll register port 0 bulkin when port had opened, It'll take all
1525 	 * port received data, MSR register change and TX_EMPTY information.
1526 	 */
1527 	mutex_lock(&serial_priv->urb_mutex);
1528 
1529 	if (serial_priv->opened_port) {
1530 		status = f81534_submit_read_urb(serial, GFP_NOIO);
1531 		if (status) {
1532 			mutex_unlock(&serial_priv->urb_mutex);
1533 			return status;
1534 		}
1535 	}
1536 
1537 	mutex_unlock(&serial_priv->urb_mutex);
1538 
1539 	for (i = 0; i < serial->num_ports; i++) {
1540 		port = serial->port[i];
1541 		if (!tty_port_initialized(&port->port))
1542 			continue;
1543 
1544 		status = f81534_submit_writer(port, GFP_NOIO);
1545 		if (status) {
1546 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1547 			++error;
1548 		}
1549 	}
1550 
1551 	if (error)
1552 		return -EIO;
1553 
1554 	return 0;
1555 }
1556 
1557 static struct usb_serial_driver f81534_device = {
1558 	.driver = {
1559 		   .owner = THIS_MODULE,
1560 		   .name = "f81534",
1561 	},
1562 	.description =		DRIVER_DESC,
1563 	.id_table =		f81534_id_table,
1564 	.num_bulk_in =		1,
1565 	.num_bulk_out =		1,
1566 	.open =			f81534_open,
1567 	.close =		f81534_close,
1568 	.write =		f81534_write,
1569 	.tx_empty =		f81534_tx_empty,
1570 	.calc_num_ports =	f81534_calc_num_ports,
1571 	.port_probe =		f81534_port_probe,
1572 	.port_remove =		f81534_port_remove,
1573 	.break_ctl =		f81534_break_ctl,
1574 	.dtr_rts =		f81534_dtr_rts,
1575 	.process_read_urb =	f81534_process_read_urb,
1576 	.get_serial =		f81534_get_serial_info,
1577 	.tiocmget =		f81534_tiocmget,
1578 	.tiocmset =		f81534_tiocmset,
1579 	.write_bulk_callback =	f81534_write_usb_callback,
1580 	.set_termios =		f81534_set_termios,
1581 	.resume =		f81534_resume,
1582 };
1583 
1584 static struct usb_serial_driver *const serial_drivers[] = {
1585 	&f81534_device, NULL
1586 };
1587 
1588 module_usb_serial_driver(serial_drivers, f81534_id_table);
1589 
1590 MODULE_DEVICE_TABLE(usb, f81534_id_table);
1591 MODULE_DESCRIPTION(DRIVER_DESC);
1592 MODULE_AUTHOR("Peter Hong <Peter_Hong@fintek.com.tw>");
1593 MODULE_AUTHOR("Tom Tsai <Tom_Tsai@fintek.com.tw>");
1594 MODULE_LICENSE("GPL");
1595