xref: /linux/drivers/usb/serial/mos7840.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Clean ups from Moschip version and a few ioctl implementations by:
4  *	Paul B Schroeder <pschroeder "at" uplogix "dot" com>
5  *
6  * Originally based on drivers/usb/serial/io_edgeport.c which is:
7  *      Copyright (C) 2000 Inside Out Networks, All rights reserved.
8  *      Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
9  *
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/tty.h>
16 #include <linux/tty_driver.h>
17 #include <linux/tty_flip.h>
18 #include <linux/module.h>
19 #include <linux/serial.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/uaccess.h>
23 
24 #define DRIVER_DESC "Moschip 7840/7820 USB Serial Driver"
25 
26 /*
27  * 16C50 UART register defines
28  */
29 
30 #define LCR_BITS_5             0x00	/* 5 bits/char */
31 #define LCR_BITS_6             0x01	/* 6 bits/char */
32 #define LCR_BITS_7             0x02	/* 7 bits/char */
33 #define LCR_BITS_8             0x03	/* 8 bits/char */
34 #define LCR_BITS_MASK          0x03	/* Mask for bits/char field */
35 
36 #define LCR_STOP_1             0x00	/* 1 stop bit */
37 #define LCR_STOP_1_5           0x04	/* 1.5 stop bits (if 5   bits/char) */
38 #define LCR_STOP_2             0x04	/* 2 stop bits   (if 6-8 bits/char) */
39 #define LCR_STOP_MASK          0x04	/* Mask for stop bits field */
40 
41 #define LCR_PAR_NONE           0x00	/* No parity */
42 #define LCR_PAR_ODD            0x08	/* Odd parity */
43 #define LCR_PAR_EVEN           0x18	/* Even parity */
44 #define LCR_PAR_MARK           0x28	/* Force parity bit to 1 */
45 #define LCR_PAR_SPACE          0x38	/* Force parity bit to 0 */
46 #define LCR_PAR_MASK           0x38	/* Mask for parity field */
47 
48 #define LCR_SET_BREAK          0x40	/* Set Break condition */
49 #define LCR_DL_ENABLE          0x80	/* Enable access to divisor latch */
50 
51 #define MCR_DTR                0x01	/* Assert DTR */
52 #define MCR_RTS                0x02	/* Assert RTS */
53 #define MCR_OUT1               0x04	/* Loopback only: Sets state of RI */
54 #define MCR_MASTER_IE          0x08	/* Enable interrupt outputs */
55 #define MCR_LOOPBACK           0x10	/* Set internal (digital) loopback mode */
56 #define MCR_XON_ANY            0x20	/* Enable any char to exit XOFF mode */
57 
58 #define MOS7840_MSR_CTS        0x10	/* Current state of CTS */
59 #define MOS7840_MSR_DSR        0x20	/* Current state of DSR */
60 #define MOS7840_MSR_RI         0x40	/* Current state of RI */
61 #define MOS7840_MSR_CD         0x80	/* Current state of CD */
62 
63 /*
64  * Defines used for sending commands to port
65  */
66 
67 #define MOS_WDR_TIMEOUT		5000	/* default urb timeout */
68 
69 #define MOS_PORT1       0x0200
70 #define MOS_PORT2       0x0300
71 #define MOS_VENREG      0x0000
72 #define MOS_MAX_PORT	0x02
73 #define MOS_WRITE       0x0E
74 #define MOS_READ        0x0D
75 
76 /* Requests */
77 #define MCS_RD_RTYPE    0xC0
78 #define MCS_WR_RTYPE    0x40
79 #define MCS_RDREQ       0x0D
80 #define MCS_WRREQ       0x0E
81 #define MCS_CTRL_TIMEOUT        500
82 #define VENDOR_READ_LENGTH      (0x01)
83 
84 #define MAX_NAME_LEN    64
85 
86 #define ZLP_REG1  0x3A		/* Zero_Flag_Reg1    58 */
87 #define ZLP_REG5  0x3E		/* Zero_Flag_Reg5    62 */
88 
89 /* For higher baud Rates use TIOCEXBAUD */
90 #define TIOCEXBAUD     0x5462
91 
92 /*
93  * Vendor id and device id defines
94  *
95  * NOTE: Do not add new defines, add entries directly to the id_table instead.
96  */
97 #define USB_VENDOR_ID_BANDB              0x0856
98 #define BANDB_DEVICE_ID_USO9ML2_2        0xAC22
99 #define BANDB_DEVICE_ID_USO9ML2_2P       0xBC00
100 #define BANDB_DEVICE_ID_USO9ML2_4        0xAC24
101 #define BANDB_DEVICE_ID_USO9ML2_4P       0xBC01
102 #define BANDB_DEVICE_ID_US9ML2_2         0xAC29
103 #define BANDB_DEVICE_ID_US9ML2_4         0xAC30
104 #define BANDB_DEVICE_ID_USPTL4_2         0xAC31
105 #define BANDB_DEVICE_ID_USPTL4_4         0xAC32
106 #define BANDB_DEVICE_ID_USOPTL4_2        0xAC42
107 #define BANDB_DEVICE_ID_USOPTL4_2P       0xBC02
108 #define BANDB_DEVICE_ID_USOPTL4_4        0xAC44
109 #define BANDB_DEVICE_ID_USOPTL4_4P       0xBC03
110 
111 /* Interrupt Routine Defines    */
112 
113 #define SERIAL_IIR_RLS      0x06
114 #define SERIAL_IIR_MS       0x00
115 
116 /*
117  *  Emulation of the bit mask on the LINE STATUS REGISTER.
118  */
119 #define SERIAL_LSR_DR       0x0001
120 #define SERIAL_LSR_OE       0x0002
121 #define SERIAL_LSR_PE       0x0004
122 #define SERIAL_LSR_FE       0x0008
123 #define SERIAL_LSR_BI       0x0010
124 
125 #define MOS_MSR_DELTA_CTS   0x10
126 #define MOS_MSR_DELTA_DSR   0x20
127 #define MOS_MSR_DELTA_RI    0x40
128 #define MOS_MSR_DELTA_CD    0x80
129 
130 /* Serial Port register Address */
131 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
132 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
133 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
134 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
135 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
136 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
137 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
138 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
139 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
140 
141 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
142 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
143 #define GPIO_REGISTER              ((__u16)(0x07))
144 
145 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
146 
147 /*
148  * URB POOL related defines
149  */
150 #define NUM_URBS                        16	/* URB Count */
151 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
152 
153 /* LED on/off milliseconds*/
154 #define LED_ON_MS	500
155 #define LED_OFF_MS	500
156 
157 enum mos7840_flag {
158 	MOS7840_FLAG_LED_BUSY,
159 };
160 
161 #define MCS_PORT_MASK	GENMASK(2, 0)
162 #define MCS_PORTS(nr)	((nr) & MCS_PORT_MASK)
163 #define MCS_LED		BIT(3)
164 
165 #define MCS_DEVICE(vid, pid, flags) \
166 		USB_DEVICE((vid), (pid)), .driver_info = (flags)
167 
168 static const struct usb_device_id id_table[] = {
169 	{ MCS_DEVICE(0x0557, 0x2011, MCS_PORTS(4)) },	/* ATEN UC2324 */
170 	{ MCS_DEVICE(0x0557, 0x7820, MCS_PORTS(2)) },	/* ATEN UC2322 */
171 	{ MCS_DEVICE(0x110a, 0x2210, MCS_PORTS(2)) },	/* Moxa UPort 2210 */
172 	{ MCS_DEVICE(0x9710, 0x7810, MCS_PORTS(1) | MCS_LED) }, /* ASIX MCS7810 */
173 	{ MCS_DEVICE(0x9710, 0x7820, MCS_PORTS(2)) },	/* MosChip MCS7820 */
174 	{ MCS_DEVICE(0x9710, 0x7840, MCS_PORTS(4)) },	/* MosChip MCS7840 */
175 	{ MCS_DEVICE(0x9710, 0x7843, MCS_PORTS(3)) },	/* ASIX MCS7840 3 port */
176 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2) },
177 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P) },
178 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4) },
179 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P) },
180 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2) },
181 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4) },
182 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2) },
183 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4) },
184 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2) },
185 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P) },
186 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4) },
187 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P) },
188 	{}			/* terminating entry */
189 };
190 MODULE_DEVICE_TABLE(usb, id_table);
191 
192 /* This structure holds all of the local port information */
193 
194 struct moschip_port {
195 	int port_num;		/*Actual port number in the device(1,2,etc) */
196 	struct urb *read_urb;	/* read URB for this port */
197 	__u8 shadowLCR;		/* last LCR value received */
198 	__u8 shadowMCR;		/* last MCR value received */
199 	struct usb_serial_port *port;	/* loop back to the owner of this object */
200 
201 	/* Offsets */
202 	__u8 SpRegOffset;
203 	__u8 ControlRegOffset;
204 	__u8 DcrRegOffset;
205 
206 	spinlock_t pool_lock;
207 	struct urb *write_urb_pool[NUM_URBS];
208 	char busy[NUM_URBS];
209 	bool read_urb_busy;
210 
211 	/* For device(s) with LED indicator */
212 	bool has_led;
213 	struct timer_list led_timer1;	/* Timer for LED on */
214 	struct timer_list led_timer2;	/* Timer for LED off */
215 	struct urb *led_urb;
216 	struct usb_ctrlrequest *led_dr;
217 
218 	unsigned long flags;
219 };
220 
221 /*
222  * mos7840_set_reg_sync
223  * 	To set the Control register by calling usb_fill_control_urb function
224  *	by passing usb_sndctrlpipe function as parameter.
225  */
226 
227 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
228 				__u16 val)
229 {
230 	struct usb_device *dev = port->serial->dev;
231 	val = val & 0x00ff;
232 	dev_dbg(&port->dev, "mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
233 
234 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
235 			       MCS_WR_RTYPE, val, reg, NULL, 0,
236 			       MOS_WDR_TIMEOUT);
237 }
238 
239 /*
240  * mos7840_get_reg_sync
241  * 	To set the Uart register by calling usb_fill_control_urb function by
242  *	passing usb_rcvctrlpipe function as parameter.
243  */
244 
245 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
246 				__u16 *val)
247 {
248 	struct usb_device *dev = port->serial->dev;
249 	int ret = 0;
250 	u8 *buf;
251 
252 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
253 	if (!buf)
254 		return -ENOMEM;
255 
256 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
257 			      MCS_RD_RTYPE, 0, reg, buf, VENDOR_READ_LENGTH,
258 			      MOS_WDR_TIMEOUT);
259 	if (ret < VENDOR_READ_LENGTH) {
260 		if (ret >= 0)
261 			ret = -EIO;
262 		goto out;
263 	}
264 
265 	*val = buf[0];
266 	dev_dbg(&port->dev, "%s offset is %x, return val %x\n", __func__, reg, *val);
267 out:
268 	kfree(buf);
269 	return ret;
270 }
271 
272 /*
273  * mos7840_set_uart_reg
274  *	To set the Uart register by calling usb_fill_control_urb function by
275  *	passing usb_sndctrlpipe function as parameter.
276  */
277 
278 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
279 				__u16 val)
280 {
281 
282 	struct usb_device *dev = port->serial->dev;
283 	val = val & 0x00ff;
284 	/* For the UART control registers, the application number need
285 	   to be Or'ed */
286 	if (port->serial->num_ports == 2 && port->port_number != 0)
287 		val |= ((__u16)port->port_number + 2) << 8;
288 	else
289 		val |= ((__u16)port->port_number + 1) << 8;
290 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, val);
291 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
292 			       MCS_WR_RTYPE, val, reg, NULL, 0,
293 			       MOS_WDR_TIMEOUT);
294 
295 }
296 
297 /*
298  * mos7840_get_uart_reg
299  *	To set the Control register by calling usb_fill_control_urb function
300  *	by passing usb_rcvctrlpipe function as parameter.
301  */
302 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
303 				__u16 *val)
304 {
305 	struct usb_device *dev = port->serial->dev;
306 	int ret = 0;
307 	__u16 Wval;
308 	u8 *buf;
309 
310 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
311 	if (!buf)
312 		return -ENOMEM;
313 
314 	/* Wval  is same as application number */
315 	if (port->serial->num_ports == 2 && port->port_number != 0)
316 		Wval = ((__u16)port->port_number + 2) << 8;
317 	else
318 		Wval = ((__u16)port->port_number + 1) << 8;
319 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, Wval);
320 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
321 			      MCS_RD_RTYPE, Wval, reg, buf, VENDOR_READ_LENGTH,
322 			      MOS_WDR_TIMEOUT);
323 	if (ret < VENDOR_READ_LENGTH) {
324 		if (ret >= 0)
325 			ret = -EIO;
326 		goto out;
327 	}
328 	*val = buf[0];
329 out:
330 	kfree(buf);
331 	return ret;
332 }
333 
334 static void mos7840_dump_serial_port(struct usb_serial_port *port,
335 				     struct moschip_port *mos7840_port)
336 {
337 
338 	dev_dbg(&port->dev, "SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
339 	dev_dbg(&port->dev, "ControlRegOffset is %2x\n", mos7840_port->ControlRegOffset);
340 	dev_dbg(&port->dev, "DCRRegOffset is %2x\n", mos7840_port->DcrRegOffset);
341 
342 }
343 
344 /************************************************************************/
345 /************************************************************************/
346 /*            U S B  C A L L B A C K   F U N C T I O N S                */
347 /*            U S B  C A L L B A C K   F U N C T I O N S                */
348 /************************************************************************/
349 /************************************************************************/
350 
351 static void mos7840_set_led_callback(struct urb *urb)
352 {
353 	switch (urb->status) {
354 	case 0:
355 		/* Success */
356 		break;
357 	case -ECONNRESET:
358 	case -ENOENT:
359 	case -ESHUTDOWN:
360 		/* This urb is terminated, clean up */
361 		dev_dbg(&urb->dev->dev, "%s - urb shutting down: %d\n",
362 			__func__, urb->status);
363 		break;
364 	default:
365 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status: %d\n",
366 			__func__, urb->status);
367 	}
368 }
369 
370 static void mos7840_set_led_async(struct moschip_port *mcs, __u16 wval,
371 				__u16 reg)
372 {
373 	struct usb_device *dev = mcs->port->serial->dev;
374 	struct usb_ctrlrequest *dr = mcs->led_dr;
375 
376 	dr->bRequestType = MCS_WR_RTYPE;
377 	dr->bRequest = MCS_WRREQ;
378 	dr->wValue = cpu_to_le16(wval);
379 	dr->wIndex = cpu_to_le16(reg);
380 	dr->wLength = cpu_to_le16(0);
381 
382 	usb_fill_control_urb(mcs->led_urb, dev, usb_sndctrlpipe(dev, 0),
383 		(unsigned char *)dr, NULL, 0, mos7840_set_led_callback, NULL);
384 
385 	usb_submit_urb(mcs->led_urb, GFP_ATOMIC);
386 }
387 
388 static void mos7840_set_led_sync(struct usb_serial_port *port, __u16 reg,
389 				__u16 val)
390 {
391 	struct usb_device *dev = port->serial->dev;
392 
393 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ, MCS_WR_RTYPE,
394 			val, reg, NULL, 0, MOS_WDR_TIMEOUT);
395 }
396 
397 static void mos7840_led_off(struct timer_list *t)
398 {
399 	struct moschip_port *mcs = from_timer(mcs, t, led_timer1);
400 
401 	/* Turn off LED */
402 	mos7840_set_led_async(mcs, 0x0300, MODEM_CONTROL_REGISTER);
403 	mod_timer(&mcs->led_timer2,
404 				jiffies + msecs_to_jiffies(LED_OFF_MS));
405 }
406 
407 static void mos7840_led_flag_off(struct timer_list *t)
408 {
409 	struct moschip_port *mcs = from_timer(mcs, t, led_timer2);
410 
411 	clear_bit_unlock(MOS7840_FLAG_LED_BUSY, &mcs->flags);
412 }
413 
414 static void mos7840_led_activity(struct usb_serial_port *port)
415 {
416 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
417 
418 	if (test_and_set_bit_lock(MOS7840_FLAG_LED_BUSY, &mos7840_port->flags))
419 		return;
420 
421 	mos7840_set_led_async(mos7840_port, 0x0301, MODEM_CONTROL_REGISTER);
422 	mod_timer(&mos7840_port->led_timer1,
423 				jiffies + msecs_to_jiffies(LED_ON_MS));
424 }
425 
426 /*****************************************************************************
427  * mos7840_bulk_in_callback
428  *	this is the callback function for when we have received data on the
429  *	bulk in endpoint.
430  *****************************************************************************/
431 
432 static void mos7840_bulk_in_callback(struct urb *urb)
433 {
434 	struct moschip_port *mos7840_port = urb->context;
435 	struct usb_serial_port *port = mos7840_port->port;
436 	int retval;
437 	unsigned char *data;
438 	int status = urb->status;
439 
440 	if (status) {
441 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
442 		mos7840_port->read_urb_busy = false;
443 		return;
444 	}
445 
446 	data = urb->transfer_buffer;
447 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
448 
449 	if (urb->actual_length) {
450 		struct tty_port *tport = &mos7840_port->port->port;
451 		tty_insert_flip_string(tport, data, urb->actual_length);
452 		tty_flip_buffer_push(tport);
453 		port->icount.rx += urb->actual_length;
454 		dev_dbg(&port->dev, "icount.rx is %d:\n", port->icount.rx);
455 	}
456 
457 	if (mos7840_port->has_led)
458 		mos7840_led_activity(port);
459 
460 	mos7840_port->read_urb_busy = true;
461 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
462 
463 	if (retval) {
464 		dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
465 		mos7840_port->read_urb_busy = false;
466 	}
467 }
468 
469 /*****************************************************************************
470  * mos7840_bulk_out_data_callback
471  *	this is the callback function for when we have finished sending
472  *	serial data on the bulk out endpoint.
473  *****************************************************************************/
474 
475 static void mos7840_bulk_out_data_callback(struct urb *urb)
476 {
477 	struct moschip_port *mos7840_port = urb->context;
478 	struct usb_serial_port *port = mos7840_port->port;
479 	int status = urb->status;
480 	unsigned long flags;
481 	int i;
482 
483 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
484 	for (i = 0; i < NUM_URBS; i++) {
485 		if (urb == mos7840_port->write_urb_pool[i]) {
486 			mos7840_port->busy[i] = 0;
487 			break;
488 		}
489 	}
490 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
491 
492 	if (status) {
493 		dev_dbg(&port->dev, "nonzero write bulk status received:%d\n", status);
494 		return;
495 	}
496 
497 	tty_port_tty_wakeup(&port->port);
498 
499 }
500 
501 /************************************************************************/
502 /*       D R I V E R  T T Y  I N T E R F A C E  F U N C T I O N S       */
503 /************************************************************************/
504 
505 /*****************************************************************************
506  * mos7840_open
507  *	this function is called by the tty driver when a port is opened
508  *	If successful, we return 0
509  *	Otherwise we return a negative error number.
510  *****************************************************************************/
511 
512 static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
513 {
514 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
515 	struct usb_serial *serial = port->serial;
516 	int response;
517 	int j;
518 	struct urb *urb;
519 	__u16 Data;
520 	int status;
521 
522 	usb_clear_halt(serial->dev, port->write_urb->pipe);
523 	usb_clear_halt(serial->dev, port->read_urb->pipe);
524 
525 	/* Initialising the write urb pool */
526 	for (j = 0; j < NUM_URBS; ++j) {
527 		urb = usb_alloc_urb(0, GFP_KERNEL);
528 		mos7840_port->write_urb_pool[j] = urb;
529 		if (!urb)
530 			continue;
531 
532 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
533 								GFP_KERNEL);
534 		if (!urb->transfer_buffer) {
535 			usb_free_urb(urb);
536 			mos7840_port->write_urb_pool[j] = NULL;
537 			continue;
538 		}
539 	}
540 
541 /*****************************************************************************
542  * Initialize MCS7840 -- Write Init values to corresponding Registers
543  *
544  * Register Index
545  * 1 : IER
546  * 2 : FCR
547  * 3 : LCR
548  * 4 : MCR
549  *
550  * 0x08 : SP1/2 Control Reg
551  *****************************************************************************/
552 
553 	/* NEED to check the following Block */
554 
555 	Data = 0x0;
556 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
557 	if (status < 0) {
558 		dev_dbg(&port->dev, "Reading Spreg failed\n");
559 		goto err;
560 	}
561 	Data |= 0x80;
562 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
563 	if (status < 0) {
564 		dev_dbg(&port->dev, "writing Spreg failed\n");
565 		goto err;
566 	}
567 
568 	Data &= ~0x80;
569 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
570 	if (status < 0) {
571 		dev_dbg(&port->dev, "writing Spreg failed\n");
572 		goto err;
573 	}
574 	/* End of block to be checked */
575 
576 	Data = 0x0;
577 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
578 									&Data);
579 	if (status < 0) {
580 		dev_dbg(&port->dev, "Reading Controlreg failed\n");
581 		goto err;
582 	}
583 	Data |= 0x08;		/* Driver done bit */
584 	Data |= 0x20;		/* rx_disable */
585 	status = mos7840_set_reg_sync(port,
586 				mos7840_port->ControlRegOffset, Data);
587 	if (status < 0) {
588 		dev_dbg(&port->dev, "writing Controlreg failed\n");
589 		goto err;
590 	}
591 	/* do register settings here */
592 	/* Set all regs to the device default values. */
593 	/***********************************
594 	 * First Disable all interrupts.
595 	 ***********************************/
596 	Data = 0x00;
597 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
598 	if (status < 0) {
599 		dev_dbg(&port->dev, "disabling interrupts failed\n");
600 		goto err;
601 	}
602 	/* Set FIFO_CONTROL_REGISTER to the default value */
603 	Data = 0x00;
604 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
605 	if (status < 0) {
606 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
607 		goto err;
608 	}
609 
610 	Data = 0xcf;
611 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
612 	if (status < 0) {
613 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
614 		goto err;
615 	}
616 
617 	Data = 0x03;
618 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
619 	mos7840_port->shadowLCR = Data;
620 
621 	Data = 0x0b;
622 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
623 	mos7840_port->shadowMCR = Data;
624 
625 	Data = 0x00;
626 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
627 	mos7840_port->shadowLCR = Data;
628 
629 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
630 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
631 
632 	Data = 0x0c;
633 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
634 
635 	Data = 0x0;
636 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
637 
638 	Data = 0x00;
639 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
640 
641 	Data = Data & ~SERIAL_LCR_DLAB;
642 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
643 	mos7840_port->shadowLCR = Data;
644 
645 	/* clearing Bulkin and Bulkout Fifo */
646 	Data = 0x0;
647 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
648 
649 	Data = Data | 0x0c;
650 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
651 
652 	Data = Data & ~0x0c;
653 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
654 	/* Finally enable all interrupts */
655 	Data = 0x0c;
656 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
657 
658 	/* clearing rx_disable */
659 	Data = 0x0;
660 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
661 									&Data);
662 	Data = Data & ~0x20;
663 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
664 									Data);
665 
666 	/* rx_negate */
667 	Data = 0x0;
668 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
669 									&Data);
670 	Data = Data | 0x10;
671 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
672 									Data);
673 
674 	dev_dbg(&port->dev, "port number is %d\n", port->port_number);
675 	dev_dbg(&port->dev, "minor number is %d\n", port->minor);
676 	dev_dbg(&port->dev, "Bulkin endpoint is %d\n", port->bulk_in_endpointAddress);
677 	dev_dbg(&port->dev, "BulkOut endpoint is %d\n", port->bulk_out_endpointAddress);
678 	dev_dbg(&port->dev, "Interrupt endpoint is %d\n", port->interrupt_in_endpointAddress);
679 	dev_dbg(&port->dev, "port's number in the device is %d\n", mos7840_port->port_num);
680 	mos7840_port->read_urb = port->read_urb;
681 
682 	/* set up our bulk in urb */
683 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
684 		usb_fill_bulk_urb(mos7840_port->read_urb,
685 			serial->dev,
686 			usb_rcvbulkpipe(serial->dev,
687 				(port->bulk_in_endpointAddress) + 2),
688 			port->bulk_in_buffer,
689 			mos7840_port->read_urb->transfer_buffer_length,
690 			mos7840_bulk_in_callback, mos7840_port);
691 	} else {
692 		usb_fill_bulk_urb(mos7840_port->read_urb,
693 			serial->dev,
694 			usb_rcvbulkpipe(serial->dev,
695 				port->bulk_in_endpointAddress),
696 			port->bulk_in_buffer,
697 			mos7840_port->read_urb->transfer_buffer_length,
698 			mos7840_bulk_in_callback, mos7840_port);
699 	}
700 
701 	dev_dbg(&port->dev, "%s: bulkin endpoint is %d\n", __func__, port->bulk_in_endpointAddress);
702 	mos7840_port->read_urb_busy = true;
703 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
704 	if (response) {
705 		dev_err(&port->dev, "%s - Error %d submitting control urb\n",
706 			__func__, response);
707 		mos7840_port->read_urb_busy = false;
708 	}
709 
710 	/* initialize our port settings */
711 	/* Must set to enable ints! */
712 	mos7840_port->shadowMCR = MCR_MASTER_IE;
713 
714 	return 0;
715 err:
716 	for (j = 0; j < NUM_URBS; ++j) {
717 		urb = mos7840_port->write_urb_pool[j];
718 		if (!urb)
719 			continue;
720 		kfree(urb->transfer_buffer);
721 		usb_free_urb(urb);
722 	}
723 	return status;
724 }
725 
726 /*****************************************************************************
727  * mos7840_chars_in_buffer
728  *	this function is called by the tty driver when it wants to know how many
729  *	bytes of data we currently have outstanding in the port (data that has
730  *	been written, but hasn't made it out the port yet)
731  *****************************************************************************/
732 
733 static unsigned int mos7840_chars_in_buffer(struct tty_struct *tty)
734 {
735 	struct usb_serial_port *port = tty->driver_data;
736 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
737 	int i;
738 	unsigned int chars = 0;
739 	unsigned long flags;
740 
741 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
742 	for (i = 0; i < NUM_URBS; ++i) {
743 		if (mos7840_port->busy[i]) {
744 			struct urb *urb = mos7840_port->write_urb_pool[i];
745 			chars += urb->transfer_buffer_length;
746 		}
747 	}
748 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
749 	dev_dbg(&port->dev, "%s - returns %u\n", __func__, chars);
750 	return chars;
751 
752 }
753 
754 /*****************************************************************************
755  * mos7840_close
756  *	this function is called by the tty driver when a port is closed
757  *****************************************************************************/
758 
759 static void mos7840_close(struct usb_serial_port *port)
760 {
761 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
762 	int j;
763 	__u16 Data;
764 
765 	for (j = 0; j < NUM_URBS; ++j)
766 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
767 
768 	/* Freeing Write URBs */
769 	for (j = 0; j < NUM_URBS; ++j) {
770 		if (mos7840_port->write_urb_pool[j]) {
771 			kfree(mos7840_port->write_urb_pool[j]->transfer_buffer);
772 			usb_free_urb(mos7840_port->write_urb_pool[j]);
773 		}
774 	}
775 
776 	usb_kill_urb(mos7840_port->read_urb);
777 	mos7840_port->read_urb_busy = false;
778 
779 	Data = 0x0;
780 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
781 
782 	Data = 0x00;
783 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
784 }
785 
786 /*****************************************************************************
787  * mos7840_break
788  *	this function sends a break to the port
789  *****************************************************************************/
790 static int mos7840_break(struct tty_struct *tty, int break_state)
791 {
792 	struct usb_serial_port *port = tty->driver_data;
793 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
794 	unsigned char data;
795 
796 	if (break_state == -1)
797 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
798 	else
799 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
800 
801 	/* FIXME: no locking on shadowLCR anywhere in driver */
802 	mos7840_port->shadowLCR = data;
803 	dev_dbg(&port->dev, "%s mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
804 
805 	return mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
806 				    mos7840_port->shadowLCR);
807 }
808 
809 /*****************************************************************************
810  * mos7840_write_room
811  *	this function is called by the tty driver when it wants to know how many
812  *	bytes of data we can accept for a specific port.
813  *****************************************************************************/
814 
815 static unsigned int mos7840_write_room(struct tty_struct *tty)
816 {
817 	struct usb_serial_port *port = tty->driver_data;
818 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
819 	int i;
820 	unsigned int room = 0;
821 	unsigned long flags;
822 
823 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
824 	for (i = 0; i < NUM_URBS; ++i) {
825 		if (!mos7840_port->busy[i])
826 			room += URB_TRANSFER_BUFFER_SIZE;
827 	}
828 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
829 
830 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
831 	dev_dbg(&mos7840_port->port->dev, "%s - returns %u\n", __func__, room);
832 	return room;
833 
834 }
835 
836 /*****************************************************************************
837  * mos7840_write
838  *	this function is called by the tty driver when data should be written to
839  *	the port.
840  *	If successful, we return the number of bytes written, otherwise we
841  *      return a negative error number.
842  *****************************************************************************/
843 
844 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
845 			 const unsigned char *data, int count)
846 {
847 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
848 	struct usb_serial *serial = port->serial;
849 	int status;
850 	int i;
851 	int bytes_sent = 0;
852 	int transfer_size;
853 	unsigned long flags;
854 	struct urb *urb;
855 	/* __u16 Data; */
856 	const unsigned char *current_position = data;
857 
858 	/* try to find a free urb in the list */
859 	urb = NULL;
860 
861 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
862 	for (i = 0; i < NUM_URBS; ++i) {
863 		if (!mos7840_port->busy[i]) {
864 			mos7840_port->busy[i] = 1;
865 			urb = mos7840_port->write_urb_pool[i];
866 			dev_dbg(&port->dev, "URB:%d\n", i);
867 			break;
868 		}
869 	}
870 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
871 
872 	if (urb == NULL) {
873 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
874 		goto exit;
875 	}
876 
877 	if (urb->transfer_buffer == NULL) {
878 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
879 					       GFP_ATOMIC);
880 		if (!urb->transfer_buffer) {
881 			bytes_sent = -ENOMEM;
882 			goto exit;
883 		}
884 	}
885 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
886 
887 	memcpy(urb->transfer_buffer, current_position, transfer_size);
888 
889 	/* fill urb with data and submit  */
890 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
891 		usb_fill_bulk_urb(urb,
892 			serial->dev,
893 			usb_sndbulkpipe(serial->dev,
894 				(port->bulk_out_endpointAddress) + 2),
895 			urb->transfer_buffer,
896 			transfer_size,
897 			mos7840_bulk_out_data_callback, mos7840_port);
898 	} else {
899 		usb_fill_bulk_urb(urb,
900 			serial->dev,
901 			usb_sndbulkpipe(serial->dev,
902 				port->bulk_out_endpointAddress),
903 			urb->transfer_buffer,
904 			transfer_size,
905 			mos7840_bulk_out_data_callback, mos7840_port);
906 	}
907 
908 	dev_dbg(&port->dev, "bulkout endpoint is %d\n", port->bulk_out_endpointAddress);
909 
910 	if (mos7840_port->has_led)
911 		mos7840_led_activity(port);
912 
913 	/* send it down the pipe */
914 	status = usb_submit_urb(urb, GFP_ATOMIC);
915 
916 	if (status) {
917 		mos7840_port->busy[i] = 0;
918 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
919 			"with status = %d\n", __func__, status);
920 		bytes_sent = status;
921 		goto exit;
922 	}
923 	bytes_sent = transfer_size;
924 	port->icount.tx += transfer_size;
925 	dev_dbg(&port->dev, "icount.tx is %d:\n", port->icount.tx);
926 exit:
927 	return bytes_sent;
928 
929 }
930 
931 /*****************************************************************************
932  * mos7840_throttle
933  *	this function is called by the tty driver when it wants to stop the data
934  *	being read from the port.
935  *****************************************************************************/
936 
937 static void mos7840_throttle(struct tty_struct *tty)
938 {
939 	struct usb_serial_port *port = tty->driver_data;
940 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
941 	int status;
942 
943 	/* if we are implementing XON/XOFF, send the stop character */
944 	if (I_IXOFF(tty)) {
945 		unsigned char stop_char = STOP_CHAR(tty);
946 		status = mos7840_write(tty, port, &stop_char, 1);
947 		if (status <= 0)
948 			return;
949 	}
950 	/* if we are implementing RTS/CTS, toggle that line */
951 	if (C_CRTSCTS(tty)) {
952 		mos7840_port->shadowMCR &= ~MCR_RTS;
953 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
954 					 mos7840_port->shadowMCR);
955 		if (status < 0)
956 			return;
957 	}
958 }
959 
960 /*****************************************************************************
961  * mos7840_unthrottle
962  *	this function is called by the tty driver when it wants to resume
963  *	the data being read from the port (called after mos7840_throttle is
964  *	called)
965  *****************************************************************************/
966 static void mos7840_unthrottle(struct tty_struct *tty)
967 {
968 	struct usb_serial_port *port = tty->driver_data;
969 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
970 	int status;
971 
972 	/* if we are implementing XON/XOFF, send the start character */
973 	if (I_IXOFF(tty)) {
974 		unsigned char start_char = START_CHAR(tty);
975 		status = mos7840_write(tty, port, &start_char, 1);
976 		if (status <= 0)
977 			return;
978 	}
979 
980 	/* if we are implementing RTS/CTS, toggle that line */
981 	if (C_CRTSCTS(tty)) {
982 		mos7840_port->shadowMCR |= MCR_RTS;
983 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
984 					 mos7840_port->shadowMCR);
985 		if (status < 0)
986 			return;
987 	}
988 }
989 
990 static int mos7840_tiocmget(struct tty_struct *tty)
991 {
992 	struct usb_serial_port *port = tty->driver_data;
993 	unsigned int result;
994 	__u16 msr;
995 	__u16 mcr;
996 	int status;
997 
998 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
999 	if (status < 0)
1000 		return -EIO;
1001 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1002 	if (status < 0)
1003 		return -EIO;
1004 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1005 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1006 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1007 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1008 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1009 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1010 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1011 
1012 	dev_dbg(&port->dev, "%s - 0x%04X\n", __func__, result);
1013 
1014 	return result;
1015 }
1016 
1017 static int mos7840_tiocmset(struct tty_struct *tty,
1018 			    unsigned int set, unsigned int clear)
1019 {
1020 	struct usb_serial_port *port = tty->driver_data;
1021 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1022 	unsigned int mcr;
1023 	int status;
1024 
1025 	/* FIXME: What locks the port registers ? */
1026 	mcr = mos7840_port->shadowMCR;
1027 	if (clear & TIOCM_RTS)
1028 		mcr &= ~MCR_RTS;
1029 	if (clear & TIOCM_DTR)
1030 		mcr &= ~MCR_DTR;
1031 	if (clear & TIOCM_LOOP)
1032 		mcr &= ~MCR_LOOPBACK;
1033 
1034 	if (set & TIOCM_RTS)
1035 		mcr |= MCR_RTS;
1036 	if (set & TIOCM_DTR)
1037 		mcr |= MCR_DTR;
1038 	if (set & TIOCM_LOOP)
1039 		mcr |= MCR_LOOPBACK;
1040 
1041 	mos7840_port->shadowMCR = mcr;
1042 
1043 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1044 	if (status < 0) {
1045 		dev_dbg(&port->dev, "setting MODEM_CONTROL_REGISTER Failed\n");
1046 		return status;
1047 	}
1048 
1049 	return 0;
1050 }
1051 
1052 /*****************************************************************************
1053  * mos7840_calc_baud_rate_divisor
1054  *	this function calculates the proper baud rate divisor for the specified
1055  *	baud rate.
1056  *****************************************************************************/
1057 static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
1058 					  int baudRate, int *divisor,
1059 					  __u16 *clk_sel_val)
1060 {
1061 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudRate);
1062 
1063 	if (baudRate <= 115200) {
1064 		*divisor = 115200 / baudRate;
1065 		*clk_sel_val = 0x0;
1066 	}
1067 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1068 		*divisor = 230400 / baudRate;
1069 		*clk_sel_val = 0x10;
1070 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1071 		*divisor = 403200 / baudRate;
1072 		*clk_sel_val = 0x20;
1073 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1074 		*divisor = 460800 / baudRate;
1075 		*clk_sel_val = 0x30;
1076 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1077 		*divisor = 806400 / baudRate;
1078 		*clk_sel_val = 0x40;
1079 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1080 		*divisor = 921600 / baudRate;
1081 		*clk_sel_val = 0x50;
1082 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1083 		*divisor = 1572864 / baudRate;
1084 		*clk_sel_val = 0x60;
1085 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1086 		*divisor = 3145728 / baudRate;
1087 		*clk_sel_val = 0x70;
1088 	}
1089 	return 0;
1090 }
1091 
1092 /*****************************************************************************
1093  * mos7840_send_cmd_write_baud_rate
1094  *	this function sends the proper command to change the baud rate of the
1095  *	specified port.
1096  *****************************************************************************/
1097 
1098 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1099 					    int baudRate)
1100 {
1101 	struct usb_serial_port *port = mos7840_port->port;
1102 	int divisor = 0;
1103 	int status;
1104 	__u16 Data;
1105 	__u16 clk_sel_val;
1106 
1107 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudRate);
1108 	/* reset clk_uart_sel in spregOffset */
1109 	if (baudRate > 115200) {
1110 #ifdef HW_flow_control
1111 		/* NOTE: need to see the pther register to modify */
1112 		/* setting h/w flow control bit to 1 */
1113 		Data = 0x2b;
1114 		mos7840_port->shadowMCR = Data;
1115 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1116 									Data);
1117 		if (status < 0) {
1118 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1119 			return -1;
1120 		}
1121 #endif
1122 
1123 	} else {
1124 #ifdef HW_flow_control
1125 		/* setting h/w flow control bit to 0 */
1126 		Data = 0xb;
1127 		mos7840_port->shadowMCR = Data;
1128 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1129 									Data);
1130 		if (status < 0) {
1131 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1132 			return -1;
1133 		}
1134 #endif
1135 
1136 	}
1137 
1138 	if (1) {		/* baudRate <= 115200) */
1139 		clk_sel_val = 0x0;
1140 		Data = 0x0;
1141 		status = mos7840_calc_baud_rate_divisor(port, baudRate, &divisor,
1142 						   &clk_sel_val);
1143 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1144 								 &Data);
1145 		if (status < 0) {
1146 			dev_dbg(&port->dev, "reading spreg failed in set_serial_baud\n");
1147 			return -1;
1148 		}
1149 		Data = (Data & 0x8f) | clk_sel_val;
1150 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1151 								Data);
1152 		if (status < 0) {
1153 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1154 			return -1;
1155 		}
1156 		/* Calculate the Divisor */
1157 
1158 		if (status) {
1159 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1160 			return status;
1161 		}
1162 		/* Enable access to divisor latch */
1163 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1164 		mos7840_port->shadowLCR = Data;
1165 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1166 
1167 		/* Write the divisor */
1168 		Data = (unsigned char)(divisor & 0xff);
1169 		dev_dbg(&port->dev, "set_serial_baud Value to write DLL is %x\n", Data);
1170 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1171 
1172 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1173 		dev_dbg(&port->dev, "set_serial_baud Value to write DLM is %x\n", Data);
1174 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1175 
1176 		/* Disable access to divisor latch */
1177 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1178 		mos7840_port->shadowLCR = Data;
1179 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1180 
1181 	}
1182 	return status;
1183 }
1184 
1185 /*****************************************************************************
1186  * mos7840_change_port_settings
1187  *	This routine is called to set the UART on the device to match
1188  *      the specified new settings.
1189  *****************************************************************************/
1190 
1191 static void mos7840_change_port_settings(struct tty_struct *tty,
1192 					 struct moschip_port *mos7840_port,
1193 					 const struct ktermios *old_termios)
1194 {
1195 	struct usb_serial_port *port = mos7840_port->port;
1196 	int baud;
1197 	unsigned cflag;
1198 	__u8 lData;
1199 	__u8 lParity;
1200 	__u8 lStop;
1201 	int status;
1202 	__u16 Data;
1203 
1204 	lData = LCR_BITS_8;
1205 	lStop = LCR_STOP_1;
1206 	lParity = LCR_PAR_NONE;
1207 
1208 	cflag = tty->termios.c_cflag;
1209 
1210 	/* Change the number of bits */
1211 	switch (cflag & CSIZE) {
1212 	case CS5:
1213 		lData = LCR_BITS_5;
1214 		break;
1215 
1216 	case CS6:
1217 		lData = LCR_BITS_6;
1218 		break;
1219 
1220 	case CS7:
1221 		lData = LCR_BITS_7;
1222 		break;
1223 
1224 	default:
1225 	case CS8:
1226 		lData = LCR_BITS_8;
1227 		break;
1228 	}
1229 
1230 	/* Change the Parity bit */
1231 	if (cflag & PARENB) {
1232 		if (cflag & PARODD) {
1233 			lParity = LCR_PAR_ODD;
1234 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1235 		} else {
1236 			lParity = LCR_PAR_EVEN;
1237 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1238 		}
1239 
1240 	} else {
1241 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1242 	}
1243 
1244 	if (cflag & CMSPAR)
1245 		lParity = lParity | 0x20;
1246 
1247 	/* Change the Stop bit */
1248 	if (cflag & CSTOPB) {
1249 		lStop = LCR_STOP_2;
1250 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1251 	} else {
1252 		lStop = LCR_STOP_1;
1253 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1254 	}
1255 
1256 	/* Update the LCR with the correct value */
1257 	mos7840_port->shadowLCR &=
1258 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1259 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1260 
1261 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is %x\n", __func__,
1262 		mos7840_port->shadowLCR);
1263 	/* Disable Interrupts */
1264 	Data = 0x00;
1265 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1266 
1267 	Data = 0x00;
1268 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1269 
1270 	Data = 0xcf;
1271 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1272 
1273 	/* Send the updated LCR value to the mos7840 */
1274 	Data = mos7840_port->shadowLCR;
1275 
1276 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1277 
1278 	Data = 0x00b;
1279 	mos7840_port->shadowMCR = Data;
1280 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1281 	Data = 0x00b;
1282 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1283 
1284 	/* set up the MCR register and send it to the mos7840 */
1285 
1286 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1287 	if (cflag & CBAUD)
1288 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
1289 
1290 	if (cflag & CRTSCTS)
1291 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
1292 	else
1293 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
1294 
1295 	Data = mos7840_port->shadowMCR;
1296 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1297 
1298 	/* Determine divisor based on baud rate */
1299 	baud = tty_get_baud_rate(tty);
1300 
1301 	if (!baud) {
1302 		/* pick a default, any default... */
1303 		dev_dbg(&port->dev, "%s", "Picked default baud...\n");
1304 		baud = 9600;
1305 	}
1306 
1307 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1308 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
1309 
1310 	/* Enable Interrupts */
1311 	Data = 0x0c;
1312 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1313 
1314 	if (!mos7840_port->read_urb_busy) {
1315 		mos7840_port->read_urb_busy = true;
1316 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1317 		if (status) {
1318 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1319 			    status);
1320 			mos7840_port->read_urb_busy = false;
1321 		}
1322 	}
1323 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
1324 		mos7840_port->shadowLCR);
1325 }
1326 
1327 /*****************************************************************************
1328  * mos7840_set_termios
1329  *	this function is called by the tty driver when it wants to change
1330  *	the termios structure
1331  *****************************************************************************/
1332 
1333 static void mos7840_set_termios(struct tty_struct *tty,
1334 				struct usb_serial_port *port,
1335 				const struct ktermios *old_termios)
1336 {
1337 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1338 	int status;
1339 
1340 	/* change the port settings to the new ones specified */
1341 
1342 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
1343 
1344 	if (!mos7840_port->read_urb_busy) {
1345 		mos7840_port->read_urb_busy = true;
1346 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1347 		if (status) {
1348 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1349 			    status);
1350 			mos7840_port->read_urb_busy = false;
1351 		}
1352 	}
1353 }
1354 
1355 /*****************************************************************************
1356  * mos7840_get_lsr_info - get line status register info
1357  *
1358  * Purpose: Let user call ioctl() to get info when the UART physically
1359  * 	    is emptied.  On bus types like RS485, the transmitter must
1360  * 	    release the bus after transmitting. This must be done when
1361  * 	    the transmit shift register is empty, not be done when the
1362  * 	    transmit holding register is empty.  This functionality
1363  * 	    allows an RS485 driver to be written in user space.
1364  *****************************************************************************/
1365 
1366 static int mos7840_get_lsr_info(struct tty_struct *tty,
1367 				unsigned int __user *value)
1368 {
1369 	int count;
1370 	unsigned int result = 0;
1371 
1372 	count = mos7840_chars_in_buffer(tty);
1373 	if (count == 0)
1374 		result = TIOCSER_TEMT;
1375 
1376 	if (copy_to_user(value, &result, sizeof(int)))
1377 		return -EFAULT;
1378 	return 0;
1379 }
1380 
1381 /*****************************************************************************
1382  * SerialIoctl
1383  *	this function handles any ioctl calls to the driver
1384  *****************************************************************************/
1385 
1386 static int mos7840_ioctl(struct tty_struct *tty,
1387 			 unsigned int cmd, unsigned long arg)
1388 {
1389 	struct usb_serial_port *port = tty->driver_data;
1390 	void __user *argp = (void __user *)arg;
1391 
1392 	switch (cmd) {
1393 		/* return number of bytes available */
1394 
1395 	case TIOCSERGETLSR:
1396 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1397 		return mos7840_get_lsr_info(tty, argp);
1398 
1399 	default:
1400 		break;
1401 	}
1402 	return -ENOIOCTLCMD;
1403 }
1404 
1405 /*
1406  * Check if GPO (pin 42) is connected to GPI (pin 33) as recommended by ASIX
1407  * for MCS7810 by bit-banging a 16-bit word.
1408  *
1409  * Note that GPO is really RTS of the third port so this will toggle RTS of
1410  * port two or three on two- and four-port devices.
1411  */
1412 static int mos7810_check(struct usb_serial *serial)
1413 {
1414 	int i, pass_count = 0;
1415 	u8 *buf;
1416 	__u16 data = 0, mcr_data = 0;
1417 	__u16 test_pattern = 0x55AA;
1418 	int res;
1419 
1420 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1421 	if (!buf)
1422 		return 0;	/* failed to identify 7810 */
1423 
1424 	/* Store MCR setting */
1425 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1426 		MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
1427 		buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1428 	if (res == VENDOR_READ_LENGTH)
1429 		mcr_data = *buf;
1430 
1431 	for (i = 0; i < 16; i++) {
1432 		/* Send the 1-bit test pattern out to MCS7810 test pin */
1433 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1434 			MCS_WRREQ, MCS_WR_RTYPE,
1435 			(0x0300 | (((test_pattern >> i) & 0x0001) << 1)),
1436 			MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
1437 
1438 		/* Read the test pattern back */
1439 		res = usb_control_msg(serial->dev,
1440 				usb_rcvctrlpipe(serial->dev, 0), MCS_RDREQ,
1441 				MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1442 				VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1443 		if (res == VENDOR_READ_LENGTH)
1444 			data = *buf;
1445 
1446 		/* If this is a MCS7810 device, both test patterns must match */
1447 		if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
1448 			break;
1449 
1450 		pass_count++;
1451 	}
1452 
1453 	/* Restore MCR setting */
1454 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), MCS_WRREQ,
1455 		MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
1456 		0, MOS_WDR_TIMEOUT);
1457 
1458 	kfree(buf);
1459 
1460 	if (pass_count == 16)
1461 		return 1;
1462 
1463 	return 0;
1464 }
1465 
1466 static int mos7840_probe(struct usb_serial *serial,
1467 				const struct usb_device_id *id)
1468 {
1469 	unsigned long device_flags = id->driver_info;
1470 	u8 *buf;
1471 
1472 	/* Skip device-type detection if we already have device flags. */
1473 	if (device_flags)
1474 		goto out;
1475 
1476 	buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1477 	if (!buf)
1478 		return -ENOMEM;
1479 
1480 	usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1481 			MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1482 			VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1483 
1484 	/* For a MCS7840 device GPIO0 must be set to 1 */
1485 	if (buf[0] & 0x01)
1486 		device_flags = MCS_PORTS(4);
1487 	else if (mos7810_check(serial))
1488 		device_flags = MCS_PORTS(1) | MCS_LED;
1489 	else
1490 		device_flags = MCS_PORTS(2);
1491 
1492 	kfree(buf);
1493 out:
1494 	usb_set_serial_data(serial, (void *)device_flags);
1495 
1496 	return 0;
1497 }
1498 
1499 static int mos7840_calc_num_ports(struct usb_serial *serial,
1500 					struct usb_serial_endpoints *epds)
1501 {
1502 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1503 	int num_ports = MCS_PORTS(device_flags);
1504 
1505 	if (num_ports == 0 || num_ports > 4)
1506 		return -ENODEV;
1507 
1508 	if (epds->num_bulk_in < num_ports || epds->num_bulk_out < num_ports) {
1509 		dev_err(&serial->interface->dev, "missing endpoints\n");
1510 		return -ENODEV;
1511 	}
1512 
1513 	return num_ports;
1514 }
1515 
1516 static int mos7840_attach(struct usb_serial *serial)
1517 {
1518 	struct device *dev = &serial->interface->dev;
1519 	int status;
1520 	u16 val;
1521 
1522 	/* Zero Length flag enable */
1523 	val = 0x0f;
1524 	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, val);
1525 	if (status < 0)
1526 		dev_dbg(dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
1527 	else
1528 		dev_dbg(dev, "ZLP_REG5 Writing success status%d\n", status);
1529 
1530 	return status;
1531 }
1532 
1533 static int mos7840_port_probe(struct usb_serial_port *port)
1534 {
1535 	struct usb_serial *serial = port->serial;
1536 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1537 	struct moschip_port *mos7840_port;
1538 	int status;
1539 	int pnum;
1540 	__u16 Data;
1541 
1542 	/* we set up the pointers to the endpoints in the mos7840_open *
1543 	 * function, as the structures aren't created yet.             */
1544 
1545 	pnum = port->port_number;
1546 
1547 	dev_dbg(&port->dev, "mos7840_startup: configuring port %d\n", pnum);
1548 	mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
1549 	if (!mos7840_port)
1550 		return -ENOMEM;
1551 
1552 	/* Initialize all port interrupt end point to port 0 int
1553 	 * endpoint. Our device has only one interrupt end point
1554 	 * common to all port */
1555 
1556 	mos7840_port->port = port;
1557 	spin_lock_init(&mos7840_port->pool_lock);
1558 
1559 	/* minor is not initialised until later by
1560 	 * usb-serial.c:get_free_serial() and cannot therefore be used
1561 	 * to index device instances */
1562 	mos7840_port->port_num = pnum + 1;
1563 	dev_dbg(&port->dev, "port->minor = %d\n", port->minor);
1564 	dev_dbg(&port->dev, "mos7840_port->port_num = %d\n", mos7840_port->port_num);
1565 
1566 	if (mos7840_port->port_num == 1) {
1567 		mos7840_port->SpRegOffset = 0x0;
1568 		mos7840_port->ControlRegOffset = 0x1;
1569 		mos7840_port->DcrRegOffset = 0x4;
1570 	} else {
1571 		u8 phy_num = mos7840_port->port_num;
1572 
1573 		/* Port 2 in the 2-port case uses registers of port 3 */
1574 		if (serial->num_ports == 2)
1575 			phy_num = 3;
1576 
1577 		mos7840_port->SpRegOffset = 0x8 + 2 * (phy_num - 2);
1578 		mos7840_port->ControlRegOffset = 0x9 + 2 * (phy_num - 2);
1579 		mos7840_port->DcrRegOffset = 0x16 + 3 * (phy_num - 2);
1580 	}
1581 	mos7840_dump_serial_port(port, mos7840_port);
1582 	usb_set_serial_port_data(port, mos7840_port);
1583 
1584 	/* enable rx_disable bit in control register */
1585 	status = mos7840_get_reg_sync(port,
1586 			mos7840_port->ControlRegOffset, &Data);
1587 	if (status < 0) {
1588 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
1589 		goto error;
1590 	} else
1591 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
1592 	Data |= 0x08;	/* setting driver done bit */
1593 	Data |= 0x04;	/* sp1_bit to have cts change reflect in
1594 			   modem status reg */
1595 
1596 	/* Data |= 0x20; //rx_disable bit */
1597 	status = mos7840_set_reg_sync(port,
1598 			mos7840_port->ControlRegOffset, Data);
1599 	if (status < 0) {
1600 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
1601 		goto error;
1602 	} else
1603 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
1604 
1605 	/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
1606 	   and 0x24 in DCR3 */
1607 	Data = 0x01;
1608 	status = mos7840_set_reg_sync(port,
1609 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
1610 	if (status < 0) {
1611 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
1612 		goto error;
1613 	} else
1614 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
1615 
1616 	Data = 0x05;
1617 	status = mos7840_set_reg_sync(port,
1618 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
1619 	if (status < 0) {
1620 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
1621 		goto error;
1622 	} else
1623 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
1624 
1625 	Data = 0x24;
1626 	status = mos7840_set_reg_sync(port,
1627 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
1628 	if (status < 0) {
1629 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
1630 		goto error;
1631 	} else
1632 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
1633 
1634 	/* write values in clkstart0x0 and clkmulti 0x20 */
1635 	Data = 0x0;
1636 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
1637 	if (status < 0) {
1638 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
1639 		goto error;
1640 	} else
1641 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
1642 
1643 	Data = 0x20;
1644 	status = mos7840_set_reg_sync(port, CLK_MULTI_REGISTER, Data);
1645 	if (status < 0) {
1646 		dev_dbg(&port->dev, "Writing CLK_MULTI_REGISTER failed status-0x%x\n", status);
1647 		goto error;
1648 	} else
1649 		dev_dbg(&port->dev, "CLK_MULTI_REGISTER Writing success status%d\n", status);
1650 
1651 	/* write value 0x0 to scratchpad register */
1652 	Data = 0x00;
1653 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
1654 	if (status < 0) {
1655 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
1656 		goto error;
1657 	} else
1658 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
1659 
1660 	/* Zero Length flag register */
1661 	if ((mos7840_port->port_num != 1) && (serial->num_ports == 2)) {
1662 		Data = 0xff;
1663 		status = mos7840_set_reg_sync(port,
1664 				(__u16) (ZLP_REG1 +
1665 					((__u16)mos7840_port->port_num)), Data);
1666 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1667 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
1668 		if (status < 0) {
1669 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
1670 			goto error;
1671 		} else
1672 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
1673 	} else {
1674 		Data = 0xff;
1675 		status = mos7840_set_reg_sync(port,
1676 				(__u16) (ZLP_REG1 +
1677 					((__u16)mos7840_port->port_num) - 0x1), Data);
1678 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1679 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
1680 		if (status < 0) {
1681 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
1682 			goto error;
1683 		} else
1684 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
1685 
1686 	}
1687 
1688 	mos7840_port->has_led = device_flags & MCS_LED;
1689 
1690 	/* Initialize LED timers */
1691 	if (mos7840_port->has_led) {
1692 		mos7840_port->led_urb = usb_alloc_urb(0, GFP_KERNEL);
1693 		mos7840_port->led_dr = kmalloc(sizeof(*mos7840_port->led_dr),
1694 								GFP_KERNEL);
1695 		if (!mos7840_port->led_urb || !mos7840_port->led_dr) {
1696 			status = -ENOMEM;
1697 			goto error;
1698 		}
1699 
1700 		timer_setup(&mos7840_port->led_timer1, mos7840_led_off, 0);
1701 		mos7840_port->led_timer1.expires =
1702 			jiffies + msecs_to_jiffies(LED_ON_MS);
1703 		timer_setup(&mos7840_port->led_timer2, mos7840_led_flag_off,
1704 			    0);
1705 		mos7840_port->led_timer2.expires =
1706 			jiffies + msecs_to_jiffies(LED_OFF_MS);
1707 
1708 		/* Turn off LED */
1709 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1710 	}
1711 
1712 	return 0;
1713 error:
1714 	kfree(mos7840_port->led_dr);
1715 	usb_free_urb(mos7840_port->led_urb);
1716 	kfree(mos7840_port);
1717 
1718 	return status;
1719 }
1720 
1721 static void mos7840_port_remove(struct usb_serial_port *port)
1722 {
1723 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1724 
1725 	if (mos7840_port->has_led) {
1726 		/* Turn off LED */
1727 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1728 
1729 		timer_shutdown_sync(&mos7840_port->led_timer1);
1730 		timer_shutdown_sync(&mos7840_port->led_timer2);
1731 
1732 		usb_kill_urb(mos7840_port->led_urb);
1733 		usb_free_urb(mos7840_port->led_urb);
1734 		kfree(mos7840_port->led_dr);
1735 	}
1736 
1737 	kfree(mos7840_port);
1738 }
1739 
1740 static int mos7840_suspend(struct usb_serial *serial, pm_message_t message)
1741 {
1742 	struct moschip_port *mos7840_port;
1743 	struct usb_serial_port *port;
1744 	int i;
1745 
1746 	for (i = 0; i < serial->num_ports; ++i) {
1747 		port = serial->port[i];
1748 		if (!tty_port_initialized(&port->port))
1749 			continue;
1750 
1751 		mos7840_port = usb_get_serial_port_data(port);
1752 
1753 		usb_kill_urb(mos7840_port->read_urb);
1754 		mos7840_port->read_urb_busy = false;
1755 	}
1756 
1757 	return 0;
1758 }
1759 
1760 static int mos7840_resume(struct usb_serial *serial)
1761 {
1762 	struct moschip_port *mos7840_port;
1763 	struct usb_serial_port *port;
1764 	int res;
1765 	int i;
1766 
1767 	for (i = 0; i < serial->num_ports; ++i) {
1768 		port = serial->port[i];
1769 		if (!tty_port_initialized(&port->port))
1770 			continue;
1771 
1772 		mos7840_port = usb_get_serial_port_data(port);
1773 
1774 		mos7840_port->read_urb_busy = true;
1775 		res = usb_submit_urb(mos7840_port->read_urb, GFP_NOIO);
1776 		if (res)
1777 			mos7840_port->read_urb_busy = false;
1778 	}
1779 
1780 	return 0;
1781 }
1782 
1783 static struct usb_serial_driver moschip7840_4port_device = {
1784 	.driver = {
1785 		   .name = "mos7840",
1786 		   },
1787 	.description = DRIVER_DESC,
1788 	.id_table = id_table,
1789 	.num_interrupt_in = 1,
1790 	.open = mos7840_open,
1791 	.close = mos7840_close,
1792 	.write = mos7840_write,
1793 	.write_room = mos7840_write_room,
1794 	.chars_in_buffer = mos7840_chars_in_buffer,
1795 	.throttle = mos7840_throttle,
1796 	.unthrottle = mos7840_unthrottle,
1797 	.calc_num_ports = mos7840_calc_num_ports,
1798 	.probe = mos7840_probe,
1799 	.attach = mos7840_attach,
1800 	.ioctl = mos7840_ioctl,
1801 	.set_termios = mos7840_set_termios,
1802 	.break_ctl = mos7840_break,
1803 	.tiocmget = mos7840_tiocmget,
1804 	.tiocmset = mos7840_tiocmset,
1805 	.get_icount = usb_serial_generic_get_icount,
1806 	.port_probe = mos7840_port_probe,
1807 	.port_remove = mos7840_port_remove,
1808 	.read_bulk_callback = mos7840_bulk_in_callback,
1809 	.suspend = mos7840_suspend,
1810 	.resume = mos7840_resume,
1811 };
1812 
1813 static struct usb_serial_driver * const serial_drivers[] = {
1814 	&moschip7840_4port_device, NULL
1815 };
1816 
1817 module_usb_serial_driver(serial_drivers, id_table);
1818 
1819 MODULE_DESCRIPTION(DRIVER_DESC);
1820 MODULE_LICENSE("GPL");
1821