xref: /openbmc/linux/drivers/usb/serial/mos7840.c (revision a2cab953)
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 void 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 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
805 			     mos7840_port->shadowLCR);
806 }
807 
808 /*****************************************************************************
809  * mos7840_write_room
810  *	this function is called by the tty driver when it wants to know how many
811  *	bytes of data we can accept for a specific port.
812  *****************************************************************************/
813 
814 static unsigned int mos7840_write_room(struct tty_struct *tty)
815 {
816 	struct usb_serial_port *port = tty->driver_data;
817 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
818 	int i;
819 	unsigned int room = 0;
820 	unsigned long flags;
821 
822 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
823 	for (i = 0; i < NUM_URBS; ++i) {
824 		if (!mos7840_port->busy[i])
825 			room += URB_TRANSFER_BUFFER_SIZE;
826 	}
827 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
828 
829 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
830 	dev_dbg(&mos7840_port->port->dev, "%s - returns %u\n", __func__, room);
831 	return room;
832 
833 }
834 
835 /*****************************************************************************
836  * mos7840_write
837  *	this function is called by the tty driver when data should be written to
838  *	the port.
839  *	If successful, we return the number of bytes written, otherwise we
840  *      return a negative error number.
841  *****************************************************************************/
842 
843 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
844 			 const unsigned char *data, int count)
845 {
846 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
847 	struct usb_serial *serial = port->serial;
848 	int status;
849 	int i;
850 	int bytes_sent = 0;
851 	int transfer_size;
852 	unsigned long flags;
853 	struct urb *urb;
854 	/* __u16 Data; */
855 	const unsigned char *current_position = data;
856 
857 	/* try to find a free urb in the list */
858 	urb = NULL;
859 
860 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
861 	for (i = 0; i < NUM_URBS; ++i) {
862 		if (!mos7840_port->busy[i]) {
863 			mos7840_port->busy[i] = 1;
864 			urb = mos7840_port->write_urb_pool[i];
865 			dev_dbg(&port->dev, "URB:%d\n", i);
866 			break;
867 		}
868 	}
869 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
870 
871 	if (urb == NULL) {
872 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
873 		goto exit;
874 	}
875 
876 	if (urb->transfer_buffer == NULL) {
877 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
878 					       GFP_ATOMIC);
879 		if (!urb->transfer_buffer) {
880 			bytes_sent = -ENOMEM;
881 			goto exit;
882 		}
883 	}
884 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
885 
886 	memcpy(urb->transfer_buffer, current_position, transfer_size);
887 
888 	/* fill urb with data and submit  */
889 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
890 		usb_fill_bulk_urb(urb,
891 			serial->dev,
892 			usb_sndbulkpipe(serial->dev,
893 				(port->bulk_out_endpointAddress) + 2),
894 			urb->transfer_buffer,
895 			transfer_size,
896 			mos7840_bulk_out_data_callback, mos7840_port);
897 	} else {
898 		usb_fill_bulk_urb(urb,
899 			serial->dev,
900 			usb_sndbulkpipe(serial->dev,
901 				port->bulk_out_endpointAddress),
902 			urb->transfer_buffer,
903 			transfer_size,
904 			mos7840_bulk_out_data_callback, mos7840_port);
905 	}
906 
907 	dev_dbg(&port->dev, "bulkout endpoint is %d\n", port->bulk_out_endpointAddress);
908 
909 	if (mos7840_port->has_led)
910 		mos7840_led_activity(port);
911 
912 	/* send it down the pipe */
913 	status = usb_submit_urb(urb, GFP_ATOMIC);
914 
915 	if (status) {
916 		mos7840_port->busy[i] = 0;
917 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
918 			"with status = %d\n", __func__, status);
919 		bytes_sent = status;
920 		goto exit;
921 	}
922 	bytes_sent = transfer_size;
923 	port->icount.tx += transfer_size;
924 	dev_dbg(&port->dev, "icount.tx is %d:\n", port->icount.tx);
925 exit:
926 	return bytes_sent;
927 
928 }
929 
930 /*****************************************************************************
931  * mos7840_throttle
932  *	this function is called by the tty driver when it wants to stop the data
933  *	being read from the port.
934  *****************************************************************************/
935 
936 static void mos7840_throttle(struct tty_struct *tty)
937 {
938 	struct usb_serial_port *port = tty->driver_data;
939 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
940 	int status;
941 
942 	/* if we are implementing XON/XOFF, send the stop character */
943 	if (I_IXOFF(tty)) {
944 		unsigned char stop_char = STOP_CHAR(tty);
945 		status = mos7840_write(tty, port, &stop_char, 1);
946 		if (status <= 0)
947 			return;
948 	}
949 	/* if we are implementing RTS/CTS, toggle that line */
950 	if (C_CRTSCTS(tty)) {
951 		mos7840_port->shadowMCR &= ~MCR_RTS;
952 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
953 					 mos7840_port->shadowMCR);
954 		if (status < 0)
955 			return;
956 	}
957 }
958 
959 /*****************************************************************************
960  * mos7840_unthrottle
961  *	this function is called by the tty driver when it wants to resume
962  *	the data being read from the port (called after mos7840_throttle is
963  *	called)
964  *****************************************************************************/
965 static void mos7840_unthrottle(struct tty_struct *tty)
966 {
967 	struct usb_serial_port *port = tty->driver_data;
968 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
969 	int status;
970 
971 	/* if we are implementing XON/XOFF, send the start character */
972 	if (I_IXOFF(tty)) {
973 		unsigned char start_char = START_CHAR(tty);
974 		status = mos7840_write(tty, port, &start_char, 1);
975 		if (status <= 0)
976 			return;
977 	}
978 
979 	/* if we are implementing RTS/CTS, toggle that line */
980 	if (C_CRTSCTS(tty)) {
981 		mos7840_port->shadowMCR |= MCR_RTS;
982 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
983 					 mos7840_port->shadowMCR);
984 		if (status < 0)
985 			return;
986 	}
987 }
988 
989 static int mos7840_tiocmget(struct tty_struct *tty)
990 {
991 	struct usb_serial_port *port = tty->driver_data;
992 	unsigned int result;
993 	__u16 msr;
994 	__u16 mcr;
995 	int status;
996 
997 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
998 	if (status < 0)
999 		return -EIO;
1000 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1001 	if (status < 0)
1002 		return -EIO;
1003 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1004 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1005 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1006 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1007 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1008 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1009 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1010 
1011 	dev_dbg(&port->dev, "%s - 0x%04X\n", __func__, result);
1012 
1013 	return result;
1014 }
1015 
1016 static int mos7840_tiocmset(struct tty_struct *tty,
1017 			    unsigned int set, unsigned int clear)
1018 {
1019 	struct usb_serial_port *port = tty->driver_data;
1020 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1021 	unsigned int mcr;
1022 	int status;
1023 
1024 	/* FIXME: What locks the port registers ? */
1025 	mcr = mos7840_port->shadowMCR;
1026 	if (clear & TIOCM_RTS)
1027 		mcr &= ~MCR_RTS;
1028 	if (clear & TIOCM_DTR)
1029 		mcr &= ~MCR_DTR;
1030 	if (clear & TIOCM_LOOP)
1031 		mcr &= ~MCR_LOOPBACK;
1032 
1033 	if (set & TIOCM_RTS)
1034 		mcr |= MCR_RTS;
1035 	if (set & TIOCM_DTR)
1036 		mcr |= MCR_DTR;
1037 	if (set & TIOCM_LOOP)
1038 		mcr |= MCR_LOOPBACK;
1039 
1040 	mos7840_port->shadowMCR = mcr;
1041 
1042 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1043 	if (status < 0) {
1044 		dev_dbg(&port->dev, "setting MODEM_CONTROL_REGISTER Failed\n");
1045 		return status;
1046 	}
1047 
1048 	return 0;
1049 }
1050 
1051 /*****************************************************************************
1052  * mos7840_calc_baud_rate_divisor
1053  *	this function calculates the proper baud rate divisor for the specified
1054  *	baud rate.
1055  *****************************************************************************/
1056 static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
1057 					  int baudRate, int *divisor,
1058 					  __u16 *clk_sel_val)
1059 {
1060 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudRate);
1061 
1062 	if (baudRate <= 115200) {
1063 		*divisor = 115200 / baudRate;
1064 		*clk_sel_val = 0x0;
1065 	}
1066 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1067 		*divisor = 230400 / baudRate;
1068 		*clk_sel_val = 0x10;
1069 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1070 		*divisor = 403200 / baudRate;
1071 		*clk_sel_val = 0x20;
1072 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1073 		*divisor = 460800 / baudRate;
1074 		*clk_sel_val = 0x30;
1075 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1076 		*divisor = 806400 / baudRate;
1077 		*clk_sel_val = 0x40;
1078 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1079 		*divisor = 921600 / baudRate;
1080 		*clk_sel_val = 0x50;
1081 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1082 		*divisor = 1572864 / baudRate;
1083 		*clk_sel_val = 0x60;
1084 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1085 		*divisor = 3145728 / baudRate;
1086 		*clk_sel_val = 0x70;
1087 	}
1088 	return 0;
1089 }
1090 
1091 /*****************************************************************************
1092  * mos7840_send_cmd_write_baud_rate
1093  *	this function sends the proper command to change the baud rate of the
1094  *	specified port.
1095  *****************************************************************************/
1096 
1097 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1098 					    int baudRate)
1099 {
1100 	struct usb_serial_port *port = mos7840_port->port;
1101 	int divisor = 0;
1102 	int status;
1103 	__u16 Data;
1104 	__u16 clk_sel_val;
1105 
1106 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudRate);
1107 	/* reset clk_uart_sel in spregOffset */
1108 	if (baudRate > 115200) {
1109 #ifdef HW_flow_control
1110 		/* NOTE: need to see the pther register to modify */
1111 		/* setting h/w flow control bit to 1 */
1112 		Data = 0x2b;
1113 		mos7840_port->shadowMCR = Data;
1114 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1115 									Data);
1116 		if (status < 0) {
1117 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1118 			return -1;
1119 		}
1120 #endif
1121 
1122 	} else {
1123 #ifdef HW_flow_control
1124 		/* setting h/w flow control bit to 0 */
1125 		Data = 0xb;
1126 		mos7840_port->shadowMCR = Data;
1127 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1128 									Data);
1129 		if (status < 0) {
1130 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1131 			return -1;
1132 		}
1133 #endif
1134 
1135 	}
1136 
1137 	if (1) {		/* baudRate <= 115200) */
1138 		clk_sel_val = 0x0;
1139 		Data = 0x0;
1140 		status = mos7840_calc_baud_rate_divisor(port, baudRate, &divisor,
1141 						   &clk_sel_val);
1142 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1143 								 &Data);
1144 		if (status < 0) {
1145 			dev_dbg(&port->dev, "reading spreg failed in set_serial_baud\n");
1146 			return -1;
1147 		}
1148 		Data = (Data & 0x8f) | clk_sel_val;
1149 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1150 								Data);
1151 		if (status < 0) {
1152 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1153 			return -1;
1154 		}
1155 		/* Calculate the Divisor */
1156 
1157 		if (status) {
1158 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1159 			return status;
1160 		}
1161 		/* Enable access to divisor latch */
1162 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1163 		mos7840_port->shadowLCR = Data;
1164 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1165 
1166 		/* Write the divisor */
1167 		Data = (unsigned char)(divisor & 0xff);
1168 		dev_dbg(&port->dev, "set_serial_baud Value to write DLL is %x\n", Data);
1169 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1170 
1171 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1172 		dev_dbg(&port->dev, "set_serial_baud Value to write DLM is %x\n", Data);
1173 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1174 
1175 		/* Disable access to divisor latch */
1176 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1177 		mos7840_port->shadowLCR = Data;
1178 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1179 
1180 	}
1181 	return status;
1182 }
1183 
1184 /*****************************************************************************
1185  * mos7840_change_port_settings
1186  *	This routine is called to set the UART on the device to match
1187  *      the specified new settings.
1188  *****************************************************************************/
1189 
1190 static void mos7840_change_port_settings(struct tty_struct *tty,
1191 					 struct moschip_port *mos7840_port,
1192 					 const struct ktermios *old_termios)
1193 {
1194 	struct usb_serial_port *port = mos7840_port->port;
1195 	int baud;
1196 	unsigned cflag;
1197 	__u8 lData;
1198 	__u8 lParity;
1199 	__u8 lStop;
1200 	int status;
1201 	__u16 Data;
1202 
1203 	lData = LCR_BITS_8;
1204 	lStop = LCR_STOP_1;
1205 	lParity = LCR_PAR_NONE;
1206 
1207 	cflag = tty->termios.c_cflag;
1208 
1209 	/* Change the number of bits */
1210 	switch (cflag & CSIZE) {
1211 	case CS5:
1212 		lData = LCR_BITS_5;
1213 		break;
1214 
1215 	case CS6:
1216 		lData = LCR_BITS_6;
1217 		break;
1218 
1219 	case CS7:
1220 		lData = LCR_BITS_7;
1221 		break;
1222 
1223 	default:
1224 	case CS8:
1225 		lData = LCR_BITS_8;
1226 		break;
1227 	}
1228 
1229 	/* Change the Parity bit */
1230 	if (cflag & PARENB) {
1231 		if (cflag & PARODD) {
1232 			lParity = LCR_PAR_ODD;
1233 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1234 		} else {
1235 			lParity = LCR_PAR_EVEN;
1236 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1237 		}
1238 
1239 	} else {
1240 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1241 	}
1242 
1243 	if (cflag & CMSPAR)
1244 		lParity = lParity | 0x20;
1245 
1246 	/* Change the Stop bit */
1247 	if (cflag & CSTOPB) {
1248 		lStop = LCR_STOP_2;
1249 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1250 	} else {
1251 		lStop = LCR_STOP_1;
1252 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1253 	}
1254 
1255 	/* Update the LCR with the correct value */
1256 	mos7840_port->shadowLCR &=
1257 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1258 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1259 
1260 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is %x\n", __func__,
1261 		mos7840_port->shadowLCR);
1262 	/* Disable Interrupts */
1263 	Data = 0x00;
1264 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1265 
1266 	Data = 0x00;
1267 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1268 
1269 	Data = 0xcf;
1270 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1271 
1272 	/* Send the updated LCR value to the mos7840 */
1273 	Data = mos7840_port->shadowLCR;
1274 
1275 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1276 
1277 	Data = 0x00b;
1278 	mos7840_port->shadowMCR = Data;
1279 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1280 	Data = 0x00b;
1281 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1282 
1283 	/* set up the MCR register and send it to the mos7840 */
1284 
1285 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1286 	if (cflag & CBAUD)
1287 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
1288 
1289 	if (cflag & CRTSCTS)
1290 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
1291 	else
1292 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
1293 
1294 	Data = mos7840_port->shadowMCR;
1295 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1296 
1297 	/* Determine divisor based on baud rate */
1298 	baud = tty_get_baud_rate(tty);
1299 
1300 	if (!baud) {
1301 		/* pick a default, any default... */
1302 		dev_dbg(&port->dev, "%s", "Picked default baud...\n");
1303 		baud = 9600;
1304 	}
1305 
1306 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1307 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
1308 
1309 	/* Enable Interrupts */
1310 	Data = 0x0c;
1311 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1312 
1313 	if (!mos7840_port->read_urb_busy) {
1314 		mos7840_port->read_urb_busy = true;
1315 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1316 		if (status) {
1317 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1318 			    status);
1319 			mos7840_port->read_urb_busy = false;
1320 		}
1321 	}
1322 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
1323 		mos7840_port->shadowLCR);
1324 }
1325 
1326 /*****************************************************************************
1327  * mos7840_set_termios
1328  *	this function is called by the tty driver when it wants to change
1329  *	the termios structure
1330  *****************************************************************************/
1331 
1332 static void mos7840_set_termios(struct tty_struct *tty,
1333 				struct usb_serial_port *port,
1334 				const struct ktermios *old_termios)
1335 {
1336 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1337 	int status;
1338 
1339 	/* change the port settings to the new ones specified */
1340 
1341 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
1342 
1343 	if (!mos7840_port->read_urb_busy) {
1344 		mos7840_port->read_urb_busy = true;
1345 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1346 		if (status) {
1347 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1348 			    status);
1349 			mos7840_port->read_urb_busy = false;
1350 		}
1351 	}
1352 }
1353 
1354 /*****************************************************************************
1355  * mos7840_get_lsr_info - get line status register info
1356  *
1357  * Purpose: Let user call ioctl() to get info when the UART physically
1358  * 	    is emptied.  On bus types like RS485, the transmitter must
1359  * 	    release the bus after transmitting. This must be done when
1360  * 	    the transmit shift register is empty, not be done when the
1361  * 	    transmit holding register is empty.  This functionality
1362  * 	    allows an RS485 driver to be written in user space.
1363  *****************************************************************************/
1364 
1365 static int mos7840_get_lsr_info(struct tty_struct *tty,
1366 				unsigned int __user *value)
1367 {
1368 	int count;
1369 	unsigned int result = 0;
1370 
1371 	count = mos7840_chars_in_buffer(tty);
1372 	if (count == 0)
1373 		result = TIOCSER_TEMT;
1374 
1375 	if (copy_to_user(value, &result, sizeof(int)))
1376 		return -EFAULT;
1377 	return 0;
1378 }
1379 
1380 /*****************************************************************************
1381  * SerialIoctl
1382  *	this function handles any ioctl calls to the driver
1383  *****************************************************************************/
1384 
1385 static int mos7840_ioctl(struct tty_struct *tty,
1386 			 unsigned int cmd, unsigned long arg)
1387 {
1388 	struct usb_serial_port *port = tty->driver_data;
1389 	void __user *argp = (void __user *)arg;
1390 
1391 	switch (cmd) {
1392 		/* return number of bytes available */
1393 
1394 	case TIOCSERGETLSR:
1395 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1396 		return mos7840_get_lsr_info(tty, argp);
1397 
1398 	default:
1399 		break;
1400 	}
1401 	return -ENOIOCTLCMD;
1402 }
1403 
1404 /*
1405  * Check if GPO (pin 42) is connected to GPI (pin 33) as recommended by ASIX
1406  * for MCS7810 by bit-banging a 16-bit word.
1407  *
1408  * Note that GPO is really RTS of the third port so this will toggle RTS of
1409  * port two or three on two- and four-port devices.
1410  */
1411 static int mos7810_check(struct usb_serial *serial)
1412 {
1413 	int i, pass_count = 0;
1414 	u8 *buf;
1415 	__u16 data = 0, mcr_data = 0;
1416 	__u16 test_pattern = 0x55AA;
1417 	int res;
1418 
1419 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1420 	if (!buf)
1421 		return 0;	/* failed to identify 7810 */
1422 
1423 	/* Store MCR setting */
1424 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1425 		MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
1426 		buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1427 	if (res == VENDOR_READ_LENGTH)
1428 		mcr_data = *buf;
1429 
1430 	for (i = 0; i < 16; i++) {
1431 		/* Send the 1-bit test pattern out to MCS7810 test pin */
1432 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1433 			MCS_WRREQ, MCS_WR_RTYPE,
1434 			(0x0300 | (((test_pattern >> i) & 0x0001) << 1)),
1435 			MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
1436 
1437 		/* Read the test pattern back */
1438 		res = usb_control_msg(serial->dev,
1439 				usb_rcvctrlpipe(serial->dev, 0), MCS_RDREQ,
1440 				MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1441 				VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1442 		if (res == VENDOR_READ_LENGTH)
1443 			data = *buf;
1444 
1445 		/* If this is a MCS7810 device, both test patterns must match */
1446 		if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
1447 			break;
1448 
1449 		pass_count++;
1450 	}
1451 
1452 	/* Restore MCR setting */
1453 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), MCS_WRREQ,
1454 		MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
1455 		0, MOS_WDR_TIMEOUT);
1456 
1457 	kfree(buf);
1458 
1459 	if (pass_count == 16)
1460 		return 1;
1461 
1462 	return 0;
1463 }
1464 
1465 static int mos7840_probe(struct usb_serial *serial,
1466 				const struct usb_device_id *id)
1467 {
1468 	unsigned long device_flags = id->driver_info;
1469 	u8 *buf;
1470 
1471 	/* Skip device-type detection if we already have device flags. */
1472 	if (device_flags)
1473 		goto out;
1474 
1475 	buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1476 	if (!buf)
1477 		return -ENOMEM;
1478 
1479 	usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1480 			MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1481 			VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1482 
1483 	/* For a MCS7840 device GPIO0 must be set to 1 */
1484 	if (buf[0] & 0x01)
1485 		device_flags = MCS_PORTS(4);
1486 	else if (mos7810_check(serial))
1487 		device_flags = MCS_PORTS(1) | MCS_LED;
1488 	else
1489 		device_flags = MCS_PORTS(2);
1490 
1491 	kfree(buf);
1492 out:
1493 	usb_set_serial_data(serial, (void *)device_flags);
1494 
1495 	return 0;
1496 }
1497 
1498 static int mos7840_calc_num_ports(struct usb_serial *serial,
1499 					struct usb_serial_endpoints *epds)
1500 {
1501 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1502 	int num_ports = MCS_PORTS(device_flags);
1503 
1504 	if (num_ports == 0 || num_ports > 4)
1505 		return -ENODEV;
1506 
1507 	if (epds->num_bulk_in < num_ports || epds->num_bulk_out < num_ports) {
1508 		dev_err(&serial->interface->dev, "missing endpoints\n");
1509 		return -ENODEV;
1510 	}
1511 
1512 	return num_ports;
1513 }
1514 
1515 static int mos7840_attach(struct usb_serial *serial)
1516 {
1517 	struct device *dev = &serial->interface->dev;
1518 	int status;
1519 	u16 val;
1520 
1521 	/* Zero Length flag enable */
1522 	val = 0x0f;
1523 	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, val);
1524 	if (status < 0)
1525 		dev_dbg(dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
1526 	else
1527 		dev_dbg(dev, "ZLP_REG5 Writing success status%d\n", status);
1528 
1529 	return status;
1530 }
1531 
1532 static int mos7840_port_probe(struct usb_serial_port *port)
1533 {
1534 	struct usb_serial *serial = port->serial;
1535 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1536 	struct moschip_port *mos7840_port;
1537 	int status;
1538 	int pnum;
1539 	__u16 Data;
1540 
1541 	/* we set up the pointers to the endpoints in the mos7840_open *
1542 	 * function, as the structures aren't created yet.             */
1543 
1544 	pnum = port->port_number;
1545 
1546 	dev_dbg(&port->dev, "mos7840_startup: configuring port %d\n", pnum);
1547 	mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
1548 	if (!mos7840_port)
1549 		return -ENOMEM;
1550 
1551 	/* Initialize all port interrupt end point to port 0 int
1552 	 * endpoint. Our device has only one interrupt end point
1553 	 * common to all port */
1554 
1555 	mos7840_port->port = port;
1556 	spin_lock_init(&mos7840_port->pool_lock);
1557 
1558 	/* minor is not initialised until later by
1559 	 * usb-serial.c:get_free_serial() and cannot therefore be used
1560 	 * to index device instances */
1561 	mos7840_port->port_num = pnum + 1;
1562 	dev_dbg(&port->dev, "port->minor = %d\n", port->minor);
1563 	dev_dbg(&port->dev, "mos7840_port->port_num = %d\n", mos7840_port->port_num);
1564 
1565 	if (mos7840_port->port_num == 1) {
1566 		mos7840_port->SpRegOffset = 0x0;
1567 		mos7840_port->ControlRegOffset = 0x1;
1568 		mos7840_port->DcrRegOffset = 0x4;
1569 	} else {
1570 		u8 phy_num = mos7840_port->port_num;
1571 
1572 		/* Port 2 in the 2-port case uses registers of port 3 */
1573 		if (serial->num_ports == 2)
1574 			phy_num = 3;
1575 
1576 		mos7840_port->SpRegOffset = 0x8 + 2 * (phy_num - 2);
1577 		mos7840_port->ControlRegOffset = 0x9 + 2 * (phy_num - 2);
1578 		mos7840_port->DcrRegOffset = 0x16 + 3 * (phy_num - 2);
1579 	}
1580 	mos7840_dump_serial_port(port, mos7840_port);
1581 	usb_set_serial_port_data(port, mos7840_port);
1582 
1583 	/* enable rx_disable bit in control register */
1584 	status = mos7840_get_reg_sync(port,
1585 			mos7840_port->ControlRegOffset, &Data);
1586 	if (status < 0) {
1587 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
1588 		goto error;
1589 	} else
1590 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
1591 	Data |= 0x08;	/* setting driver done bit */
1592 	Data |= 0x04;	/* sp1_bit to have cts change reflect in
1593 			   modem status reg */
1594 
1595 	/* Data |= 0x20; //rx_disable bit */
1596 	status = mos7840_set_reg_sync(port,
1597 			mos7840_port->ControlRegOffset, Data);
1598 	if (status < 0) {
1599 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
1600 		goto error;
1601 	} else
1602 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
1603 
1604 	/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
1605 	   and 0x24 in DCR3 */
1606 	Data = 0x01;
1607 	status = mos7840_set_reg_sync(port,
1608 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
1609 	if (status < 0) {
1610 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
1611 		goto error;
1612 	} else
1613 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
1614 
1615 	Data = 0x05;
1616 	status = mos7840_set_reg_sync(port,
1617 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
1618 	if (status < 0) {
1619 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
1620 		goto error;
1621 	} else
1622 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
1623 
1624 	Data = 0x24;
1625 	status = mos7840_set_reg_sync(port,
1626 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
1627 	if (status < 0) {
1628 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
1629 		goto error;
1630 	} else
1631 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
1632 
1633 	/* write values in clkstart0x0 and clkmulti 0x20 */
1634 	Data = 0x0;
1635 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
1636 	if (status < 0) {
1637 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
1638 		goto error;
1639 	} else
1640 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
1641 
1642 	Data = 0x20;
1643 	status = mos7840_set_reg_sync(port, CLK_MULTI_REGISTER, Data);
1644 	if (status < 0) {
1645 		dev_dbg(&port->dev, "Writing CLK_MULTI_REGISTER failed status-0x%x\n", status);
1646 		goto error;
1647 	} else
1648 		dev_dbg(&port->dev, "CLK_MULTI_REGISTER Writing success status%d\n", status);
1649 
1650 	/* write value 0x0 to scratchpad register */
1651 	Data = 0x00;
1652 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
1653 	if (status < 0) {
1654 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
1655 		goto error;
1656 	} else
1657 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
1658 
1659 	/* Zero Length flag register */
1660 	if ((mos7840_port->port_num != 1) && (serial->num_ports == 2)) {
1661 		Data = 0xff;
1662 		status = mos7840_set_reg_sync(port,
1663 				(__u16) (ZLP_REG1 +
1664 					((__u16)mos7840_port->port_num)), Data);
1665 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1666 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
1667 		if (status < 0) {
1668 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
1669 			goto error;
1670 		} else
1671 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
1672 	} else {
1673 		Data = 0xff;
1674 		status = mos7840_set_reg_sync(port,
1675 				(__u16) (ZLP_REG1 +
1676 					((__u16)mos7840_port->port_num) - 0x1), Data);
1677 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1678 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
1679 		if (status < 0) {
1680 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
1681 			goto error;
1682 		} else
1683 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
1684 
1685 	}
1686 
1687 	mos7840_port->has_led = device_flags & MCS_LED;
1688 
1689 	/* Initialize LED timers */
1690 	if (mos7840_port->has_led) {
1691 		mos7840_port->led_urb = usb_alloc_urb(0, GFP_KERNEL);
1692 		mos7840_port->led_dr = kmalloc(sizeof(*mos7840_port->led_dr),
1693 								GFP_KERNEL);
1694 		if (!mos7840_port->led_urb || !mos7840_port->led_dr) {
1695 			status = -ENOMEM;
1696 			goto error;
1697 		}
1698 
1699 		timer_setup(&mos7840_port->led_timer1, mos7840_led_off, 0);
1700 		mos7840_port->led_timer1.expires =
1701 			jiffies + msecs_to_jiffies(LED_ON_MS);
1702 		timer_setup(&mos7840_port->led_timer2, mos7840_led_flag_off,
1703 			    0);
1704 		mos7840_port->led_timer2.expires =
1705 			jiffies + msecs_to_jiffies(LED_OFF_MS);
1706 
1707 		/* Turn off LED */
1708 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1709 	}
1710 
1711 	return 0;
1712 error:
1713 	kfree(mos7840_port->led_dr);
1714 	usb_free_urb(mos7840_port->led_urb);
1715 	kfree(mos7840_port);
1716 
1717 	return status;
1718 }
1719 
1720 static void mos7840_port_remove(struct usb_serial_port *port)
1721 {
1722 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1723 
1724 	if (mos7840_port->has_led) {
1725 		/* Turn off LED */
1726 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1727 
1728 		del_timer_sync(&mos7840_port->led_timer1);
1729 		del_timer_sync(&mos7840_port->led_timer2);
1730 
1731 		usb_kill_urb(mos7840_port->led_urb);
1732 		usb_free_urb(mos7840_port->led_urb);
1733 		kfree(mos7840_port->led_dr);
1734 	}
1735 
1736 	kfree(mos7840_port);
1737 }
1738 
1739 static struct usb_serial_driver moschip7840_4port_device = {
1740 	.driver = {
1741 		   .owner = THIS_MODULE,
1742 		   .name = "mos7840",
1743 		   },
1744 	.description = DRIVER_DESC,
1745 	.id_table = id_table,
1746 	.num_interrupt_in = 1,
1747 	.open = mos7840_open,
1748 	.close = mos7840_close,
1749 	.write = mos7840_write,
1750 	.write_room = mos7840_write_room,
1751 	.chars_in_buffer = mos7840_chars_in_buffer,
1752 	.throttle = mos7840_throttle,
1753 	.unthrottle = mos7840_unthrottle,
1754 	.calc_num_ports = mos7840_calc_num_ports,
1755 	.probe = mos7840_probe,
1756 	.attach = mos7840_attach,
1757 	.ioctl = mos7840_ioctl,
1758 	.set_termios = mos7840_set_termios,
1759 	.break_ctl = mos7840_break,
1760 	.tiocmget = mos7840_tiocmget,
1761 	.tiocmset = mos7840_tiocmset,
1762 	.get_icount = usb_serial_generic_get_icount,
1763 	.port_probe = mos7840_port_probe,
1764 	.port_remove = mos7840_port_remove,
1765 	.read_bulk_callback = mos7840_bulk_in_callback,
1766 };
1767 
1768 static struct usb_serial_driver * const serial_drivers[] = {
1769 	&moschip7840_4port_device, NULL
1770 };
1771 
1772 module_usb_serial_driver(serial_drivers, id_table);
1773 
1774 MODULE_DESCRIPTION(DRIVER_DESC);
1775 MODULE_LICENSE("GPL");
1776