xref: /linux/drivers/usb/serial/f81534.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 int 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 	return status;
680 }
681 
682 static int f81534_update_mctrl(struct usb_serial_port *port, unsigned int set,
683 				unsigned int clear)
684 {
685 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
686 	int status;
687 	u8 tmp;
688 
689 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
690 		return 0;	/* no change */
691 
692 	mutex_lock(&port_priv->mcr_mutex);
693 
694 	/* 'Set' takes precedence over 'Clear' */
695 	clear &= ~set;
696 
697 	/* Always enable UART_MCR_OUT2 */
698 	tmp = UART_MCR_OUT2 | port_priv->shadow_mcr;
699 
700 	if (clear & TIOCM_DTR)
701 		tmp &= ~UART_MCR_DTR;
702 
703 	if (clear & TIOCM_RTS)
704 		tmp &= ~UART_MCR_RTS;
705 
706 	if (set & TIOCM_DTR)
707 		tmp |= UART_MCR_DTR;
708 
709 	if (set & TIOCM_RTS)
710 		tmp |= UART_MCR_RTS;
711 
712 	status = f81534_set_port_register(port, F81534_MODEM_CONTROL_REG, tmp);
713 	if (status < 0) {
714 		dev_err(&port->dev, "%s: MCR write failed\n", __func__);
715 		mutex_unlock(&port_priv->mcr_mutex);
716 		return status;
717 	}
718 
719 	port_priv->shadow_mcr = tmp;
720 	mutex_unlock(&port_priv->mcr_mutex);
721 	return 0;
722 }
723 
724 /*
725  * This function will search the data area with token F81534_CUSTOM_VALID_TOKEN
726  * for latest configuration index. If nothing found
727  * (*index = F81534_CUSTOM_NO_CUSTOM_DATA), We'll load default configure in
728  * F81534_DEF_CONF_ADDRESS_START section.
729  *
730  * Due to we only use block0 to save data, so *index should be 0 or
731  * F81534_CUSTOM_NO_CUSTOM_DATA.
732  */
733 static int f81534_find_config_idx(struct usb_serial *serial, u8 *index)
734 {
735 	u8 tmp;
736 	int status;
737 
738 	status = f81534_read_flash(serial, F81534_CUSTOM_ADDRESS_START, 1,
739 					&tmp);
740 	if (status) {
741 		dev_err(&serial->interface->dev, "%s: read failed: %d\n",
742 				__func__, status);
743 		return status;
744 	}
745 
746 	/* We'll use the custom data when the data is valid. */
747 	if (tmp == F81534_CUSTOM_VALID_TOKEN)
748 		*index = 0;
749 	else
750 		*index = F81534_CUSTOM_NO_CUSTOM_DATA;
751 
752 	return 0;
753 }
754 
755 /*
756  * The F81532/534 will not report serial port to USB serial subsystem when
757  * H/W DCD/DSR/CTS/RI/RX pin connected to ground.
758  *
759  * To detect RX pin status, we'll enable MCR interal loopback, disable it and
760  * delayed for 60ms. It connected to ground If LSR register report UART_LSR_BI.
761  */
762 static bool f81534_check_port_hw_disabled(struct usb_serial *serial, int phy)
763 {
764 	int status;
765 	u8 old_mcr;
766 	u8 msr;
767 	u8 lsr;
768 	u8 msr_mask;
769 
770 	msr_mask = UART_MSR_DCD | UART_MSR_RI | UART_MSR_DSR | UART_MSR_CTS;
771 
772 	status = f81534_get_phy_port_register(serial, phy,
773 				F81534_MODEM_STATUS_REG, &msr);
774 	if (status)
775 		return false;
776 
777 	if ((msr & msr_mask) != msr_mask)
778 		return false;
779 
780 	status = f81534_set_phy_port_register(serial, phy,
781 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
782 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
783 	if (status)
784 		return false;
785 
786 	status = f81534_get_phy_port_register(serial, phy,
787 				F81534_MODEM_CONTROL_REG, &old_mcr);
788 	if (status)
789 		return false;
790 
791 	status = f81534_set_phy_port_register(serial, phy,
792 				F81534_MODEM_CONTROL_REG, UART_MCR_LOOP);
793 	if (status)
794 		return false;
795 
796 	status = f81534_set_phy_port_register(serial, phy,
797 				F81534_MODEM_CONTROL_REG, 0x0);
798 	if (status)
799 		return false;
800 
801 	msleep(60);
802 
803 	status = f81534_get_phy_port_register(serial, phy,
804 				F81534_LINE_STATUS_REG, &lsr);
805 	if (status)
806 		return false;
807 
808 	status = f81534_set_phy_port_register(serial, phy,
809 				F81534_MODEM_CONTROL_REG, old_mcr);
810 	if (status)
811 		return false;
812 
813 	if ((lsr & UART_LSR_BI) == UART_LSR_BI)
814 		return true;
815 
816 	return false;
817 }
818 
819 /*
820  * We had 2 generation of F81532/534 IC. All has an internal storage.
821  *
822  * 1st is pure USB-to-TTL RS232 IC and designed for 4 ports only, no any
823  * internal data will used. All mode and gpio control should manually set
824  * by AP or Driver and all storage space value are 0xff. The
825  * f81534_calc_num_ports() will run to final we marked as "oldest version"
826  * for this IC.
827  *
828  * 2rd is designed to more generic to use any transceiver and this is our
829  * mass production type. We'll save data in F81534_CUSTOM_ADDRESS_START
830  * (0x2f00) with 9bytes. The 1st byte is a indicater. If the token is
831  * F81534_CUSTOM_VALID_TOKEN(0xf0), the IC is 2nd gen type, the following
832  * 4bytes save port mode (0:RS232/1:RS485 Invert/2:RS485), and the last
833  * 4bytes save GPIO state(value from 0~7 to represent 3 GPIO output pin).
834  * The f81534_calc_num_ports() will run to "new style" with checking
835  * F81534_PORT_UNAVAILABLE section.
836  */
837 static int f81534_calc_num_ports(struct usb_serial *serial,
838 					struct usb_serial_endpoints *epds)
839 {
840 	struct f81534_serial_private *serial_priv;
841 	struct device *dev = &serial->interface->dev;
842 	int size_bulk_in = usb_endpoint_maxp(epds->bulk_in[0]);
843 	int size_bulk_out = usb_endpoint_maxp(epds->bulk_out[0]);
844 	u8 num_port = 0;
845 	int index = 0;
846 	int status;
847 	int i;
848 
849 	if (size_bulk_out != F81534_WRITE_BUFFER_SIZE ||
850 			size_bulk_in != F81534_MAX_RECEIVE_BLOCK_SIZE) {
851 		dev_err(dev, "unsupported endpoint max packet size\n");
852 		return -ENODEV;
853 	}
854 
855 	serial_priv = devm_kzalloc(&serial->interface->dev,
856 					sizeof(*serial_priv), GFP_KERNEL);
857 	if (!serial_priv)
858 		return -ENOMEM;
859 
860 	usb_set_serial_data(serial, serial_priv);
861 	mutex_init(&serial_priv->urb_mutex);
862 
863 	/* Check had custom setting */
864 	status = f81534_find_config_idx(serial, &serial_priv->setting_idx);
865 	if (status) {
866 		dev_err(&serial->interface->dev, "%s: find idx failed: %d\n",
867 				__func__, status);
868 		return status;
869 	}
870 
871 	/*
872 	 * We'll read custom data only when data available, otherwise we'll
873 	 * read default value instead.
874 	 */
875 	if (serial_priv->setting_idx != F81534_CUSTOM_NO_CUSTOM_DATA) {
876 		status = f81534_read_flash(serial,
877 						F81534_CUSTOM_ADDRESS_START +
878 						F81534_CONF_OFFSET,
879 						sizeof(serial_priv->conf_data),
880 						serial_priv->conf_data);
881 		if (status) {
882 			dev_err(&serial->interface->dev,
883 					"%s: get custom data failed: %d\n",
884 					__func__, status);
885 			return status;
886 		}
887 
888 		dev_dbg(&serial->interface->dev,
889 				"%s: read config from block: %d\n", __func__,
890 				serial_priv->setting_idx);
891 	} else {
892 		/* Read default board setting */
893 		status = f81534_read_flash(serial,
894 				F81534_DEF_CONF_ADDRESS_START,
895 				sizeof(serial_priv->conf_data),
896 				serial_priv->conf_data);
897 		if (status) {
898 			dev_err(&serial->interface->dev,
899 					"%s: read failed: %d\n", __func__,
900 					status);
901 			return status;
902 		}
903 
904 		dev_dbg(&serial->interface->dev, "%s: read default config\n",
905 				__func__);
906 	}
907 
908 	/* New style, find all possible ports */
909 	for (i = 0; i < F81534_NUM_PORT; ++i) {
910 		if (f81534_check_port_hw_disabled(serial, i))
911 			serial_priv->conf_data[i] |= F81534_PORT_UNAVAILABLE;
912 
913 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
914 			continue;
915 
916 		++num_port;
917 	}
918 
919 	if (!num_port) {
920 		dev_warn(&serial->interface->dev,
921 			"no config found, assuming 4 ports\n");
922 		num_port = 4;		/* Nothing found, oldest version IC */
923 	}
924 
925 	/* Assign phy-to-logic mapping */
926 	for (i = 0; i < F81534_NUM_PORT; ++i) {
927 		if (serial_priv->conf_data[i] & F81534_PORT_UNAVAILABLE)
928 			continue;
929 
930 		serial_priv->tty_idx[i] = index++;
931 		dev_dbg(&serial->interface->dev,
932 				"%s: phy_num: %d, tty_idx: %d\n", __func__, i,
933 				serial_priv->tty_idx[i]);
934 	}
935 
936 	/*
937 	 * Setup bulk-out endpoint multiplexing. All ports share the same
938 	 * bulk-out endpoint.
939 	 */
940 	BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < F81534_NUM_PORT);
941 
942 	for (i = 1; i < num_port; ++i)
943 		epds->bulk_out[i] = epds->bulk_out[0];
944 
945 	epds->num_bulk_out = num_port;
946 
947 	return num_port;
948 }
949 
950 static void f81534_set_termios(struct tty_struct *tty,
951 			       struct usb_serial_port *port,
952 			       const struct ktermios *old_termios)
953 {
954 	u8 new_lcr = 0;
955 	int status;
956 	u32 baud;
957 	u32 old_baud;
958 
959 	if (C_BAUD(tty) == B0)
960 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
961 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
962 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
963 
964 	if (C_PARENB(tty)) {
965 		new_lcr |= UART_LCR_PARITY;
966 
967 		if (!C_PARODD(tty))
968 			new_lcr |= UART_LCR_EPAR;
969 
970 		if (C_CMSPAR(tty))
971 			new_lcr |= UART_LCR_SPAR;
972 	}
973 
974 	if (C_CSTOPB(tty))
975 		new_lcr |= UART_LCR_STOP;
976 
977 	new_lcr |= UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
978 
979 	baud = tty_get_baud_rate(tty);
980 	if (!baud)
981 		return;
982 
983 	if (old_termios)
984 		old_baud = tty_termios_baud_rate(old_termios);
985 	else
986 		old_baud = F81534_DEFAULT_BAUD_RATE;
987 
988 	dev_dbg(&port->dev, "%s: baud: %d\n", __func__, baud);
989 
990 	status = f81534_set_port_config(port, tty, baud, old_baud, new_lcr);
991 	if (status < 0) {
992 		dev_err(&port->dev, "%s: set port config failed: %d\n",
993 				__func__, status);
994 	}
995 }
996 
997 static int f81534_submit_read_urb(struct usb_serial *serial, gfp_t flags)
998 {
999 	return usb_serial_generic_submit_read_urbs(serial->port[0], flags);
1000 }
1001 
1002 static void f81534_msr_changed(struct usb_serial_port *port, u8 msr)
1003 {
1004 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1005 	struct tty_struct *tty;
1006 	unsigned long flags;
1007 	u8 old_msr;
1008 
1009 	if (!(msr & UART_MSR_ANY_DELTA))
1010 		return;
1011 
1012 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1013 	old_msr = port_priv->shadow_msr;
1014 	port_priv->shadow_msr = msr;
1015 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1016 
1017 	dev_dbg(&port->dev, "%s: MSR from %02x to %02x\n", __func__, old_msr,
1018 			msr);
1019 
1020 	/* Update input line counters */
1021 	if (msr & UART_MSR_DCTS)
1022 		port->icount.cts++;
1023 	if (msr & UART_MSR_DDSR)
1024 		port->icount.dsr++;
1025 	if (msr & UART_MSR_DDCD)
1026 		port->icount.dcd++;
1027 	if (msr & UART_MSR_TERI)
1028 		port->icount.rng++;
1029 
1030 	wake_up_interruptible(&port->port.delta_msr_wait);
1031 
1032 	if (!(msr & UART_MSR_DDCD))
1033 		return;
1034 
1035 	dev_dbg(&port->dev, "%s: DCD Changed: phy_num: %d from %x to %x\n",
1036 			__func__, port_priv->phy_num, old_msr, msr);
1037 
1038 	tty = tty_port_tty_get(&port->port);
1039 	if (!tty)
1040 		return;
1041 
1042 	usb_serial_handle_dcd_change(port, tty, msr & UART_MSR_DCD);
1043 	tty_kref_put(tty);
1044 }
1045 
1046 static int f81534_read_msr(struct usb_serial_port *port)
1047 {
1048 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1049 	unsigned long flags;
1050 	int status;
1051 	u8 msr;
1052 
1053 	/* Get MSR initial value */
1054 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1055 	if (status)
1056 		return status;
1057 
1058 	/* Force update current state */
1059 	spin_lock_irqsave(&port_priv->msr_lock, flags);
1060 	port_priv->shadow_msr = msr;
1061 	spin_unlock_irqrestore(&port_priv->msr_lock, flags);
1062 
1063 	return 0;
1064 }
1065 
1066 static int f81534_open(struct tty_struct *tty, struct usb_serial_port *port)
1067 {
1068 	struct f81534_serial_private *serial_priv =
1069 			usb_get_serial_data(port->serial);
1070 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1071 	int status;
1072 
1073 	status = f81534_set_port_register(port,
1074 				F81534_FIFO_CONTROL_REG, UART_FCR_ENABLE_FIFO |
1075 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
1076 	if (status) {
1077 		dev_err(&port->dev, "%s: Clear FIFO failed: %d\n", __func__,
1078 				status);
1079 		return status;
1080 	}
1081 
1082 	if (tty)
1083 		f81534_set_termios(tty, port, NULL);
1084 
1085 	status = f81534_read_msr(port);
1086 	if (status)
1087 		return status;
1088 
1089 	mutex_lock(&serial_priv->urb_mutex);
1090 
1091 	/* Submit Read URBs for first port opened */
1092 	if (!serial_priv->opened_port) {
1093 		status = f81534_submit_read_urb(port->serial, GFP_KERNEL);
1094 		if (status)
1095 			goto exit;
1096 	}
1097 
1098 	serial_priv->opened_port++;
1099 
1100 exit:
1101 	mutex_unlock(&serial_priv->urb_mutex);
1102 
1103 	set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1104 	return status;
1105 }
1106 
1107 static void f81534_close(struct usb_serial_port *port)
1108 {
1109 	struct f81534_serial_private *serial_priv =
1110 			usb_get_serial_data(port->serial);
1111 	struct usb_serial_port *port0 = port->serial->port[0];
1112 	unsigned long flags;
1113 	size_t i;
1114 
1115 	usb_kill_urb(port->write_urbs[0]);
1116 
1117 	spin_lock_irqsave(&port->lock, flags);
1118 	kfifo_reset_out(&port->write_fifo);
1119 	spin_unlock_irqrestore(&port->lock, flags);
1120 
1121 	/* Kill Read URBs when final port closed */
1122 	mutex_lock(&serial_priv->urb_mutex);
1123 	serial_priv->opened_port--;
1124 
1125 	if (!serial_priv->opened_port) {
1126 		for (i = 0; i < ARRAY_SIZE(port0->read_urbs); ++i)
1127 			usb_kill_urb(port0->read_urbs[i]);
1128 	}
1129 
1130 	mutex_unlock(&serial_priv->urb_mutex);
1131 }
1132 
1133 static void f81534_get_serial_info(struct tty_struct *tty, struct serial_struct *ss)
1134 {
1135 	struct usb_serial_port *port = tty->driver_data;
1136 	struct f81534_port_private *port_priv;
1137 
1138 	port_priv = usb_get_serial_port_data(port);
1139 
1140 	ss->baud_base = port_priv->baud_base;
1141 }
1142 
1143 static void f81534_process_per_serial_block(struct usb_serial_port *port,
1144 		u8 *data)
1145 {
1146 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1147 	int phy_num = data[0];
1148 	size_t read_size = 0;
1149 	size_t i;
1150 	char tty_flag;
1151 	int status;
1152 	u8 lsr;
1153 
1154 	/*
1155 	 * The block layout is 128 Bytes
1156 	 * index 0: port phy idx (e.g., 0,1,2,3),
1157 	 * index 1: It's could be
1158 	 *			F81534_TOKEN_RECEIVE
1159 	 *			F81534_TOKEN_TX_EMPTY
1160 	 *			F81534_TOKEN_MSR_CHANGE
1161 	 * index 2: serial in size (data+lsr, must be even)
1162 	 *			meaningful for F81534_TOKEN_RECEIVE only
1163 	 * index 3: current MSR with this device
1164 	 * index 4~127: serial in data block (data+lsr, must be even)
1165 	 */
1166 	switch (data[1]) {
1167 	case F81534_TOKEN_TX_EMPTY:
1168 		set_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1169 
1170 		/* Try to submit writer */
1171 		status = f81534_submit_writer(port, GFP_ATOMIC);
1172 		if (status)
1173 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1174 		return;
1175 
1176 	case F81534_TOKEN_MSR_CHANGE:
1177 		f81534_msr_changed(port, data[3]);
1178 		return;
1179 
1180 	case F81534_TOKEN_RECEIVE:
1181 		read_size = data[2];
1182 		if (read_size > F81534_MAX_RX_SIZE) {
1183 			dev_err(&port->dev,
1184 				"%s: phy: %d read_size: %zu larger than: %d\n",
1185 				__func__, phy_num, read_size,
1186 				F81534_MAX_RX_SIZE);
1187 			return;
1188 		}
1189 
1190 		break;
1191 
1192 	default:
1193 		dev_warn(&port->dev, "%s: unknown token: %02x\n", __func__,
1194 				data[1]);
1195 		return;
1196 	}
1197 
1198 	for (i = 4; i < 4 + read_size; i += 2) {
1199 		tty_flag = TTY_NORMAL;
1200 		lsr = data[i + 1];
1201 
1202 		if (lsr & UART_LSR_BRK_ERROR_BITS) {
1203 			if (lsr & UART_LSR_BI) {
1204 				tty_flag = TTY_BREAK;
1205 				port->icount.brk++;
1206 				usb_serial_handle_break(port);
1207 			} else if (lsr & UART_LSR_PE) {
1208 				tty_flag = TTY_PARITY;
1209 				port->icount.parity++;
1210 			} else if (lsr & UART_LSR_FE) {
1211 				tty_flag = TTY_FRAME;
1212 				port->icount.frame++;
1213 			}
1214 
1215 			if (lsr & UART_LSR_OE) {
1216 				port->icount.overrun++;
1217 				tty_insert_flip_char(&port->port, 0,
1218 						TTY_OVERRUN);
1219 			}
1220 
1221 			schedule_work(&port_priv->lsr_work);
1222 		}
1223 
1224 		if (port->sysrq) {
1225 			if (usb_serial_handle_sysrq_char(port, data[i]))
1226 				continue;
1227 		}
1228 
1229 		tty_insert_flip_char(&port->port, data[i], tty_flag);
1230 	}
1231 
1232 	tty_flip_buffer_push(&port->port);
1233 }
1234 
1235 static void f81534_process_read_urb(struct urb *urb)
1236 {
1237 	struct f81534_serial_private *serial_priv;
1238 	struct usb_serial_port *port;
1239 	struct usb_serial *serial;
1240 	u8 *buf;
1241 	int phy_port_num;
1242 	int tty_port_num;
1243 	size_t i;
1244 
1245 	if (!urb->actual_length ||
1246 			urb->actual_length % F81534_RECEIVE_BLOCK_SIZE) {
1247 		return;
1248 	}
1249 
1250 	port = urb->context;
1251 	serial = port->serial;
1252 	buf = urb->transfer_buffer;
1253 	serial_priv = usb_get_serial_data(serial);
1254 
1255 	for (i = 0; i < urb->actual_length; i += F81534_RECEIVE_BLOCK_SIZE) {
1256 		phy_port_num = buf[i];
1257 		if (phy_port_num >= F81534_NUM_PORT) {
1258 			dev_err(&port->dev,
1259 				"%s: phy_port_num: %d larger than: %d\n",
1260 				__func__, phy_port_num, F81534_NUM_PORT);
1261 			continue;
1262 		}
1263 
1264 		tty_port_num = serial_priv->tty_idx[phy_port_num];
1265 		port = serial->port[tty_port_num];
1266 
1267 		if (tty_port_initialized(&port->port))
1268 			f81534_process_per_serial_block(port, &buf[i]);
1269 	}
1270 }
1271 
1272 static void f81534_write_usb_callback(struct urb *urb)
1273 {
1274 	struct usb_serial_port *port = urb->context;
1275 
1276 	switch (urb->status) {
1277 	case 0:
1278 		break;
1279 	case -ENOENT:
1280 	case -ECONNRESET:
1281 	case -ESHUTDOWN:
1282 		dev_dbg(&port->dev, "%s - urb stopped: %d\n",
1283 				__func__, urb->status);
1284 		return;
1285 	case -EPIPE:
1286 		dev_err(&port->dev, "%s - urb stopped: %d\n",
1287 				__func__, urb->status);
1288 		return;
1289 	default:
1290 		dev_dbg(&port->dev, "%s - nonzero urb status: %d\n",
1291 				__func__, urb->status);
1292 		break;
1293 	}
1294 }
1295 
1296 static void f81534_lsr_worker(struct work_struct *work)
1297 {
1298 	struct f81534_port_private *port_priv;
1299 	struct usb_serial_port *port;
1300 	int status;
1301 	u8 tmp;
1302 
1303 	port_priv = container_of(work, struct f81534_port_private, lsr_work);
1304 	port = port_priv->port;
1305 
1306 	status = f81534_get_port_register(port, F81534_LINE_STATUS_REG, &tmp);
1307 	if (status)
1308 		dev_warn(&port->dev, "read LSR failed: %d\n", status);
1309 }
1310 
1311 static int f81534_set_port_output_pin(struct usb_serial_port *port)
1312 {
1313 	struct f81534_serial_private *serial_priv;
1314 	struct f81534_port_private *port_priv;
1315 	struct usb_serial *serial;
1316 	const struct f81534_port_out_pin *pins;
1317 	int status;
1318 	int i;
1319 	u8 value;
1320 	u8 idx;
1321 
1322 	serial = port->serial;
1323 	serial_priv = usb_get_serial_data(serial);
1324 	port_priv = usb_get_serial_port_data(port);
1325 
1326 	idx = F81534_CONF_INIT_GPIO_OFFSET + port_priv->phy_num;
1327 	value = serial_priv->conf_data[idx];
1328 	if (value >= F81534_CONF_GPIO_SHUTDOWN) {
1329 		/*
1330 		 * Newer IC configure will make transceiver in shutdown mode on
1331 		 * initial power on. We need enable it before using UARTs.
1332 		 */
1333 		idx = F81534_CONF_WORK_GPIO_OFFSET + port_priv->phy_num;
1334 		value = serial_priv->conf_data[idx];
1335 		if (value >= F81534_CONF_GPIO_SHUTDOWN)
1336 			value = F81534_CONF_GPIO_RS232;
1337 	}
1338 
1339 	pins = &f81534_port_out_pins[port_priv->phy_num];
1340 
1341 	for (i = 0; i < ARRAY_SIZE(pins->pin); ++i) {
1342 		status = f81534_set_mask_register(serial,
1343 				pins->pin[i].reg_addr, pins->pin[i].reg_mask,
1344 				value & BIT(i) ? pins->pin[i].reg_mask : 0);
1345 		if (status)
1346 			return status;
1347 	}
1348 
1349 	dev_dbg(&port->dev, "Output pin (M0/M1/M2): %d\n", value);
1350 	return 0;
1351 }
1352 
1353 static int f81534_port_probe(struct usb_serial_port *port)
1354 {
1355 	struct f81534_serial_private *serial_priv;
1356 	struct f81534_port_private *port_priv;
1357 	int ret;
1358 	u8 value;
1359 
1360 	serial_priv = usb_get_serial_data(port->serial);
1361 	port_priv = devm_kzalloc(&port->dev, sizeof(*port_priv), GFP_KERNEL);
1362 	if (!port_priv)
1363 		return -ENOMEM;
1364 
1365 	/*
1366 	 * We'll make tx frame error when baud rate from 384~500kps. So we'll
1367 	 * delay all tx data frame with 1bit.
1368 	 */
1369 	port_priv->shadow_clk = F81534_UART_EN | F81534_CLK_TX_DELAY_1BIT;
1370 	spin_lock_init(&port_priv->msr_lock);
1371 	mutex_init(&port_priv->mcr_mutex);
1372 	mutex_init(&port_priv->lcr_mutex);
1373 	INIT_WORK(&port_priv->lsr_work, f81534_lsr_worker);
1374 
1375 	/* Assign logic-to-phy mapping */
1376 	ret = f81534_logic_to_phy_port(port->serial, port);
1377 	if (ret < 0)
1378 		return ret;
1379 
1380 	port_priv->phy_num = ret;
1381 	port_priv->port = port;
1382 	usb_set_serial_port_data(port, port_priv);
1383 	dev_dbg(&port->dev, "%s: port_number: %d, phy_num: %d\n", __func__,
1384 			port->port_number, port_priv->phy_num);
1385 
1386 	/*
1387 	 * The F81532/534 will hang-up when enable LSR interrupt in IER and
1388 	 * occur data overrun. So we'll disable the LSR interrupt in probe()
1389 	 * and submit the LSR worker to clear LSR state when reported LSR error
1390 	 * bit with bulk-in data in f81534_process_per_serial_block().
1391 	 */
1392 	ret = f81534_set_port_register(port, F81534_INTERRUPT_ENABLE_REG,
1393 			UART_IER_RDI | UART_IER_THRI | UART_IER_MSI);
1394 	if (ret)
1395 		return ret;
1396 
1397 	value = serial_priv->conf_data[port_priv->phy_num];
1398 	switch (value & F81534_PORT_CONF_MODE_MASK) {
1399 	case F81534_PORT_CONF_RS485_INVERT:
1400 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE |
1401 					F81534_CLK_RS485_INVERT;
1402 		dev_dbg(&port->dev, "RS485 invert mode\n");
1403 		break;
1404 	case F81534_PORT_CONF_RS485:
1405 		port_priv->shadow_clk |= F81534_CLK_RS485_MODE;
1406 		dev_dbg(&port->dev, "RS485 mode\n");
1407 		break;
1408 
1409 	default:
1410 	case F81534_PORT_CONF_RS232:
1411 		dev_dbg(&port->dev, "RS232 mode\n");
1412 		break;
1413 	}
1414 
1415 	return f81534_set_port_output_pin(port);
1416 }
1417 
1418 static void f81534_port_remove(struct usb_serial_port *port)
1419 {
1420 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1421 
1422 	flush_work(&port_priv->lsr_work);
1423 }
1424 
1425 static int f81534_tiocmget(struct tty_struct *tty)
1426 {
1427 	struct usb_serial_port *port = tty->driver_data;
1428 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1429 	int status;
1430 	int r;
1431 	u8 msr;
1432 	u8 mcr;
1433 
1434 	/* Read current MSR from device */
1435 	status = f81534_get_port_register(port, F81534_MODEM_STATUS_REG, &msr);
1436 	if (status)
1437 		return status;
1438 
1439 	mutex_lock(&port_priv->mcr_mutex);
1440 	mcr = port_priv->shadow_mcr;
1441 	mutex_unlock(&port_priv->mcr_mutex);
1442 
1443 	r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
1444 	    (mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
1445 	    (msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
1446 	    (msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
1447 	    (msr & UART_MSR_RI ? TIOCM_RI : 0) |
1448 	    (msr & UART_MSR_DSR ? TIOCM_DSR : 0);
1449 
1450 	return r;
1451 }
1452 
1453 static int f81534_tiocmset(struct tty_struct *tty, unsigned int set,
1454 				unsigned int clear)
1455 {
1456 	struct usb_serial_port *port = tty->driver_data;
1457 
1458 	return f81534_update_mctrl(port, set, clear);
1459 }
1460 
1461 static void f81534_dtr_rts(struct usb_serial_port *port, int on)
1462 {
1463 	if (on)
1464 		f81534_update_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
1465 	else
1466 		f81534_update_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
1467 }
1468 
1469 static int f81534_write(struct tty_struct *tty, struct usb_serial_port *port,
1470 			const u8 *buf, int count)
1471 {
1472 	int bytes_out, status;
1473 
1474 	if (!count)
1475 		return 0;
1476 
1477 	bytes_out = kfifo_in_locked(&port->write_fifo, buf, count,
1478 					&port->lock);
1479 
1480 	status = f81534_submit_writer(port, GFP_ATOMIC);
1481 	if (status) {
1482 		dev_err(&port->dev, "%s: submit failed\n", __func__);
1483 		return status;
1484 	}
1485 
1486 	return bytes_out;
1487 }
1488 
1489 static bool f81534_tx_empty(struct usb_serial_port *port)
1490 {
1491 	struct f81534_port_private *port_priv = usb_get_serial_port_data(port);
1492 
1493 	return test_bit(F81534_TX_EMPTY_BIT, &port_priv->tx_empty);
1494 }
1495 
1496 static int f81534_resume(struct usb_serial *serial)
1497 {
1498 	struct f81534_serial_private *serial_priv =
1499 			usb_get_serial_data(serial);
1500 	struct usb_serial_port *port;
1501 	int error = 0;
1502 	int status;
1503 	size_t i;
1504 
1505 	/*
1506 	 * We'll register port 0 bulkin when port had opened, It'll take all
1507 	 * port received data, MSR register change and TX_EMPTY information.
1508 	 */
1509 	mutex_lock(&serial_priv->urb_mutex);
1510 
1511 	if (serial_priv->opened_port) {
1512 		status = f81534_submit_read_urb(serial, GFP_NOIO);
1513 		if (status) {
1514 			mutex_unlock(&serial_priv->urb_mutex);
1515 			return status;
1516 		}
1517 	}
1518 
1519 	mutex_unlock(&serial_priv->urb_mutex);
1520 
1521 	for (i = 0; i < serial->num_ports; i++) {
1522 		port = serial->port[i];
1523 		if (!tty_port_initialized(&port->port))
1524 			continue;
1525 
1526 		status = f81534_submit_writer(port, GFP_NOIO);
1527 		if (status) {
1528 			dev_err(&port->dev, "%s: submit failed\n", __func__);
1529 			++error;
1530 		}
1531 	}
1532 
1533 	if (error)
1534 		return -EIO;
1535 
1536 	return 0;
1537 }
1538 
1539 static struct usb_serial_driver f81534_device = {
1540 	.driver = {
1541 		   .name = "f81534",
1542 	},
1543 	.description =		DRIVER_DESC,
1544 	.id_table =		f81534_id_table,
1545 	.num_bulk_in =		1,
1546 	.num_bulk_out =		1,
1547 	.open =			f81534_open,
1548 	.close =		f81534_close,
1549 	.write =		f81534_write,
1550 	.tx_empty =		f81534_tx_empty,
1551 	.calc_num_ports =	f81534_calc_num_ports,
1552 	.port_probe =		f81534_port_probe,
1553 	.port_remove =		f81534_port_remove,
1554 	.break_ctl =		f81534_break_ctl,
1555 	.dtr_rts =		f81534_dtr_rts,
1556 	.process_read_urb =	f81534_process_read_urb,
1557 	.get_serial =		f81534_get_serial_info,
1558 	.tiocmget =		f81534_tiocmget,
1559 	.tiocmset =		f81534_tiocmset,
1560 	.write_bulk_callback =	f81534_write_usb_callback,
1561 	.set_termios =		f81534_set_termios,
1562 	.resume =		f81534_resume,
1563 };
1564 
1565 static struct usb_serial_driver *const serial_drivers[] = {
1566 	&f81534_device, NULL
1567 };
1568 
1569 module_usb_serial_driver(serial_drivers, f81534_id_table);
1570 
1571 MODULE_DEVICE_TABLE(usb, f81534_id_table);
1572 MODULE_DESCRIPTION(DRIVER_DESC);
1573 MODULE_AUTHOR("Peter Hong <Peter_Hong@fintek.com.tw>");
1574 MODULE_AUTHOR("Tom Tsai <Tom_Tsai@fintek.com.tw>");
1575 MODULE_LICENSE("GPL");
1576