xref: /linux/drivers/usb/serial/mos7840.c (revision e5e95a7639ed5f7dc3e404858ad7910de5fa2057)
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 #define BANDB_DEVICE_ID_USOPTL2_4        0xAC24
111 
112 /* Interrupt Routine Defines    */
113 
114 #define SERIAL_IIR_RLS      0x06
115 #define SERIAL_IIR_MS       0x00
116 
117 /*
118  *  Emulation of the bit mask on the LINE STATUS REGISTER.
119  */
120 #define SERIAL_LSR_DR       0x0001
121 #define SERIAL_LSR_OE       0x0002
122 #define SERIAL_LSR_PE       0x0004
123 #define SERIAL_LSR_FE       0x0008
124 #define SERIAL_LSR_BI       0x0010
125 
126 #define MOS_MSR_DELTA_CTS   0x10
127 #define MOS_MSR_DELTA_DSR   0x20
128 #define MOS_MSR_DELTA_RI    0x40
129 #define MOS_MSR_DELTA_CD    0x80
130 
131 /* Serial Port register Address */
132 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
133 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
134 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
135 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
136 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
137 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
138 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
139 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
140 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
141 
142 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
143 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
144 #define GPIO_REGISTER              ((__u16)(0x07))
145 
146 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
147 
148 /*
149  * URB POOL related defines
150  */
151 #define NUM_URBS                        16	/* URB Count */
152 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
153 
154 /* LED on/off milliseconds*/
155 #define LED_ON_MS	500
156 #define LED_OFF_MS	500
157 
158 enum mos7840_flag {
159 	MOS7840_FLAG_LED_BUSY,
160 };
161 
162 #define MCS_PORT_MASK	GENMASK(2, 0)
163 #define MCS_PORTS(nr)	((nr) & MCS_PORT_MASK)
164 #define MCS_LED		BIT(3)
165 
166 #define MCS_DEVICE(vid, pid, flags) \
167 		USB_DEVICE((vid), (pid)), .driver_info = (flags)
168 
169 static const struct usb_device_id id_table[] = {
170 	{ MCS_DEVICE(0x0557, 0x2011, MCS_PORTS(4)) },	/* ATEN UC2324 */
171 	{ MCS_DEVICE(0x0557, 0x7820, MCS_PORTS(2)) },	/* ATEN UC2322 */
172 	{ MCS_DEVICE(0x110a, 0x2210, MCS_PORTS(2)) },	/* Moxa UPort 2210 */
173 	{ MCS_DEVICE(0x9710, 0x7810, MCS_PORTS(1) | MCS_LED) }, /* ASIX MCS7810 */
174 	{ MCS_DEVICE(0x9710, 0x7820, MCS_PORTS(2)) },	/* MosChip MCS7820 */
175 	{ MCS_DEVICE(0x9710, 0x7840, MCS_PORTS(4)) },	/* MosChip MCS7840 */
176 	{ MCS_DEVICE(0x9710, 0x7843, MCS_PORTS(3)) },	/* ASIX MCS7840 3 port */
177 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2) },
178 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P) },
179 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4) },
180 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P) },
181 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2) },
182 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4) },
183 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2) },
184 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4) },
185 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2) },
186 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P) },
187 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4) },
188 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P) },
189 	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL2_4) },
190 	{}			/* terminating entry */
191 };
192 MODULE_DEVICE_TABLE(usb, id_table);
193 
194 /* This structure holds all of the local port information */
195 
196 struct moschip_port {
197 	int port_num;		/*Actual port number in the device(1,2,etc) */
198 	struct urb *read_urb;	/* read URB for this port */
199 	__u8 shadowLCR;		/* last LCR value received */
200 	__u8 shadowMCR;		/* last MCR value received */
201 	struct usb_serial_port *port;	/* loop back to the owner of this object */
202 
203 	/* Offsets */
204 	__u8 SpRegOffset;
205 	__u8 ControlRegOffset;
206 	__u8 DcrRegOffset;
207 
208 	spinlock_t pool_lock;
209 	struct urb *write_urb_pool[NUM_URBS];
210 	char busy[NUM_URBS];
211 	bool read_urb_busy;
212 
213 	/* For device(s) with LED indicator */
214 	bool has_led;
215 	struct timer_list led_timer1;	/* Timer for LED on */
216 	struct timer_list led_timer2;	/* Timer for LED off */
217 	struct urb *led_urb;
218 	struct usb_ctrlrequest *led_dr;
219 
220 	unsigned long flags;
221 };
222 
223 /*
224  * mos7840_set_reg_sync
225  * 	To set the Control register by calling usb_fill_control_urb function
226  *	by passing usb_sndctrlpipe function as parameter.
227  */
228 
229 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
230 				__u16 val)
231 {
232 	struct usb_device *dev = port->serial->dev;
233 	val = val & 0x00ff;
234 	dev_dbg(&port->dev, "mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
235 
236 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
237 			       MCS_WR_RTYPE, val, reg, NULL, 0,
238 			       MOS_WDR_TIMEOUT);
239 }
240 
241 /*
242  * mos7840_get_reg_sync
243  * 	To set the Uart register by calling usb_fill_control_urb function by
244  *	passing usb_rcvctrlpipe function as parameter.
245  */
246 
247 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
248 				__u16 *val)
249 {
250 	struct usb_device *dev = port->serial->dev;
251 	int ret = 0;
252 	u8 *buf;
253 
254 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
255 	if (!buf)
256 		return -ENOMEM;
257 
258 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
259 			      MCS_RD_RTYPE, 0, reg, buf, VENDOR_READ_LENGTH,
260 			      MOS_WDR_TIMEOUT);
261 	if (ret < VENDOR_READ_LENGTH) {
262 		if (ret >= 0)
263 			ret = -EIO;
264 		goto out;
265 	}
266 
267 	*val = buf[0];
268 	dev_dbg(&port->dev, "%s offset is %x, return val %x\n", __func__, reg, *val);
269 out:
270 	kfree(buf);
271 	return ret;
272 }
273 
274 /*
275  * mos7840_set_uart_reg
276  *	To set the Uart register by calling usb_fill_control_urb function by
277  *	passing usb_sndctrlpipe function as parameter.
278  */
279 
280 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
281 				__u16 val)
282 {
283 
284 	struct usb_device *dev = port->serial->dev;
285 	val = val & 0x00ff;
286 	/* For the UART control registers, the application number need
287 	   to be Or'ed */
288 	if (port->serial->num_ports == 2 && port->port_number != 0)
289 		val |= ((__u16)port->port_number + 2) << 8;
290 	else
291 		val |= ((__u16)port->port_number + 1) << 8;
292 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, val);
293 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
294 			       MCS_WR_RTYPE, val, reg, NULL, 0,
295 			       MOS_WDR_TIMEOUT);
296 
297 }
298 
299 /*
300  * mos7840_get_uart_reg
301  *	To set the Control register by calling usb_fill_control_urb function
302  *	by passing usb_rcvctrlpipe function as parameter.
303  */
304 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
305 				__u16 *val)
306 {
307 	struct usb_device *dev = port->serial->dev;
308 	int ret = 0;
309 	__u16 Wval;
310 	u8 *buf;
311 
312 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
313 	if (!buf)
314 		return -ENOMEM;
315 
316 	/* Wval  is same as application number */
317 	if (port->serial->num_ports == 2 && port->port_number != 0)
318 		Wval = ((__u16)port->port_number + 2) << 8;
319 	else
320 		Wval = ((__u16)port->port_number + 1) << 8;
321 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, Wval);
322 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
323 			      MCS_RD_RTYPE, Wval, reg, buf, VENDOR_READ_LENGTH,
324 			      MOS_WDR_TIMEOUT);
325 	if (ret < VENDOR_READ_LENGTH) {
326 		if (ret >= 0)
327 			ret = -EIO;
328 		goto out;
329 	}
330 	*val = buf[0];
331 out:
332 	kfree(buf);
333 	return ret;
334 }
335 
336 static void mos7840_dump_serial_port(struct usb_serial_port *port,
337 				     struct moschip_port *mos7840_port)
338 {
339 
340 	dev_dbg(&port->dev, "SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
341 	dev_dbg(&port->dev, "ControlRegOffset is %2x\n", mos7840_port->ControlRegOffset);
342 	dev_dbg(&port->dev, "DCRRegOffset is %2x\n", mos7840_port->DcrRegOffset);
343 
344 }
345 
346 /************************************************************************/
347 /************************************************************************/
348 /*            U S B  C A L L B A C K   F U N C T I O N S                */
349 /*            U S B  C A L L B A C K   F U N C T I O N S                */
350 /************************************************************************/
351 /************************************************************************/
352 
353 static void mos7840_set_led_callback(struct urb *urb)
354 {
355 	switch (urb->status) {
356 	case 0:
357 		/* Success */
358 		break;
359 	case -ECONNRESET:
360 	case -ENOENT:
361 	case -ESHUTDOWN:
362 		/* This urb is terminated, clean up */
363 		dev_dbg(&urb->dev->dev, "%s - urb shutting down: %d\n",
364 			__func__, urb->status);
365 		break;
366 	default:
367 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status: %d\n",
368 			__func__, urb->status);
369 	}
370 }
371 
372 static void mos7840_set_led_async(struct moschip_port *mcs, __u16 wval,
373 				__u16 reg)
374 {
375 	struct usb_device *dev = mcs->port->serial->dev;
376 	struct usb_ctrlrequest *dr = mcs->led_dr;
377 
378 	dr->bRequestType = MCS_WR_RTYPE;
379 	dr->bRequest = MCS_WRREQ;
380 	dr->wValue = cpu_to_le16(wval);
381 	dr->wIndex = cpu_to_le16(reg);
382 	dr->wLength = cpu_to_le16(0);
383 
384 	usb_fill_control_urb(mcs->led_urb, dev, usb_sndctrlpipe(dev, 0),
385 		(unsigned char *)dr, NULL, 0, mos7840_set_led_callback, NULL);
386 
387 	usb_submit_urb(mcs->led_urb, GFP_ATOMIC);
388 }
389 
390 static void mos7840_set_led_sync(struct usb_serial_port *port, __u16 reg,
391 				__u16 val)
392 {
393 	struct usb_device *dev = port->serial->dev;
394 
395 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ, MCS_WR_RTYPE,
396 			val, reg, NULL, 0, MOS_WDR_TIMEOUT);
397 }
398 
399 static void mos7840_led_off(struct timer_list *t)
400 {
401 	struct moschip_port *mcs = from_timer(mcs, t, led_timer1);
402 
403 	/* Turn off LED */
404 	mos7840_set_led_async(mcs, 0x0300, MODEM_CONTROL_REGISTER);
405 	mod_timer(&mcs->led_timer2,
406 				jiffies + msecs_to_jiffies(LED_OFF_MS));
407 }
408 
409 static void mos7840_led_flag_off(struct timer_list *t)
410 {
411 	struct moschip_port *mcs = from_timer(mcs, t, led_timer2);
412 
413 	clear_bit_unlock(MOS7840_FLAG_LED_BUSY, &mcs->flags);
414 }
415 
416 static void mos7840_led_activity(struct usb_serial_port *port)
417 {
418 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
419 
420 	if (test_and_set_bit_lock(MOS7840_FLAG_LED_BUSY, &mos7840_port->flags))
421 		return;
422 
423 	mos7840_set_led_async(mos7840_port, 0x0301, MODEM_CONTROL_REGISTER);
424 	mod_timer(&mos7840_port->led_timer1,
425 				jiffies + msecs_to_jiffies(LED_ON_MS));
426 }
427 
428 /*****************************************************************************
429  * mos7840_bulk_in_callback
430  *	this is the callback function for when we have received data on the
431  *	bulk in endpoint.
432  *****************************************************************************/
433 
434 static void mos7840_bulk_in_callback(struct urb *urb)
435 {
436 	struct moschip_port *mos7840_port = urb->context;
437 	struct usb_serial_port *port = mos7840_port->port;
438 	int retval;
439 	unsigned char *data;
440 	int status = urb->status;
441 
442 	if (status) {
443 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
444 		mos7840_port->read_urb_busy = false;
445 		return;
446 	}
447 
448 	data = urb->transfer_buffer;
449 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
450 
451 	if (urb->actual_length) {
452 		struct tty_port *tport = &mos7840_port->port->port;
453 		tty_insert_flip_string(tport, data, urb->actual_length);
454 		tty_flip_buffer_push(tport);
455 		port->icount.rx += urb->actual_length;
456 		dev_dbg(&port->dev, "icount.rx is %d:\n", port->icount.rx);
457 	}
458 
459 	if (mos7840_port->has_led)
460 		mos7840_led_activity(port);
461 
462 	mos7840_port->read_urb_busy = true;
463 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
464 
465 	if (retval) {
466 		dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
467 		mos7840_port->read_urb_busy = false;
468 	}
469 }
470 
471 /*****************************************************************************
472  * mos7840_bulk_out_data_callback
473  *	this is the callback function for when we have finished sending
474  *	serial data on the bulk out endpoint.
475  *****************************************************************************/
476 
477 static void mos7840_bulk_out_data_callback(struct urb *urb)
478 {
479 	struct moschip_port *mos7840_port = urb->context;
480 	struct usb_serial_port *port = mos7840_port->port;
481 	int status = urb->status;
482 	unsigned long flags;
483 	int i;
484 
485 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
486 	for (i = 0; i < NUM_URBS; i++) {
487 		if (urb == mos7840_port->write_urb_pool[i]) {
488 			mos7840_port->busy[i] = 0;
489 			break;
490 		}
491 	}
492 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
493 
494 	if (status) {
495 		dev_dbg(&port->dev, "nonzero write bulk status received:%d\n", status);
496 		return;
497 	}
498 
499 	tty_port_tty_wakeup(&port->port);
500 
501 }
502 
503 /************************************************************************/
504 /*       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       */
505 /************************************************************************/
506 
507 /*****************************************************************************
508  * mos7840_open
509  *	this function is called by the tty driver when a port is opened
510  *	If successful, we return 0
511  *	Otherwise we return a negative error number.
512  *****************************************************************************/
513 
514 static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
515 {
516 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
517 	struct usb_serial *serial = port->serial;
518 	int response;
519 	int j;
520 	struct urb *urb;
521 	__u16 Data;
522 	int status;
523 
524 	usb_clear_halt(serial->dev, port->write_urb->pipe);
525 	usb_clear_halt(serial->dev, port->read_urb->pipe);
526 
527 	/* Initialising the write urb pool */
528 	for (j = 0; j < NUM_URBS; ++j) {
529 		urb = usb_alloc_urb(0, GFP_KERNEL);
530 		mos7840_port->write_urb_pool[j] = urb;
531 		if (!urb)
532 			continue;
533 
534 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
535 								GFP_KERNEL);
536 		if (!urb->transfer_buffer) {
537 			usb_free_urb(urb);
538 			mos7840_port->write_urb_pool[j] = NULL;
539 			continue;
540 		}
541 	}
542 
543 /*****************************************************************************
544  * Initialize MCS7840 -- Write Init values to corresponding Registers
545  *
546  * Register Index
547  * 1 : IER
548  * 2 : FCR
549  * 3 : LCR
550  * 4 : MCR
551  *
552  * 0x08 : SP1/2 Control Reg
553  *****************************************************************************/
554 
555 	/* NEED to check the following Block */
556 
557 	Data = 0x0;
558 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
559 	if (status < 0) {
560 		dev_dbg(&port->dev, "Reading Spreg failed\n");
561 		goto err;
562 	}
563 	Data |= 0x80;
564 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
565 	if (status < 0) {
566 		dev_dbg(&port->dev, "writing Spreg failed\n");
567 		goto err;
568 	}
569 
570 	Data &= ~0x80;
571 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
572 	if (status < 0) {
573 		dev_dbg(&port->dev, "writing Spreg failed\n");
574 		goto err;
575 	}
576 	/* End of block to be checked */
577 
578 	Data = 0x0;
579 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
580 									&Data);
581 	if (status < 0) {
582 		dev_dbg(&port->dev, "Reading Controlreg failed\n");
583 		goto err;
584 	}
585 	Data |= 0x08;		/* Driver done bit */
586 	Data |= 0x20;		/* rx_disable */
587 	status = mos7840_set_reg_sync(port,
588 				mos7840_port->ControlRegOffset, Data);
589 	if (status < 0) {
590 		dev_dbg(&port->dev, "writing Controlreg failed\n");
591 		goto err;
592 	}
593 	/* do register settings here */
594 	/* Set all regs to the device default values. */
595 	/***********************************
596 	 * First Disable all interrupts.
597 	 ***********************************/
598 	Data = 0x00;
599 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
600 	if (status < 0) {
601 		dev_dbg(&port->dev, "disabling interrupts failed\n");
602 		goto err;
603 	}
604 	/* Set FIFO_CONTROL_REGISTER to the default value */
605 	Data = 0x00;
606 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
607 	if (status < 0) {
608 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
609 		goto err;
610 	}
611 
612 	Data = 0xcf;
613 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
614 	if (status < 0) {
615 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
616 		goto err;
617 	}
618 
619 	Data = 0x03;
620 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
621 	mos7840_port->shadowLCR = Data;
622 
623 	Data = 0x0b;
624 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
625 	mos7840_port->shadowMCR = Data;
626 
627 	Data = 0x00;
628 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
629 	mos7840_port->shadowLCR = Data;
630 
631 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
632 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
633 
634 	Data = 0x0c;
635 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
636 
637 	Data = 0x0;
638 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
639 
640 	Data = 0x00;
641 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
642 
643 	Data = Data & ~SERIAL_LCR_DLAB;
644 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
645 	mos7840_port->shadowLCR = Data;
646 
647 	/* clearing Bulkin and Bulkout Fifo */
648 	Data = 0x0;
649 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
650 
651 	Data = Data | 0x0c;
652 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
653 
654 	Data = Data & ~0x0c;
655 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
656 	/* Finally enable all interrupts */
657 	Data = 0x0c;
658 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
659 
660 	/* clearing rx_disable */
661 	Data = 0x0;
662 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
663 									&Data);
664 	Data = Data & ~0x20;
665 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
666 									Data);
667 
668 	/* rx_negate */
669 	Data = 0x0;
670 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
671 									&Data);
672 	Data = Data | 0x10;
673 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
674 									Data);
675 
676 	dev_dbg(&port->dev, "port number is %d\n", port->port_number);
677 	dev_dbg(&port->dev, "minor number is %d\n", port->minor);
678 	dev_dbg(&port->dev, "Bulkin endpoint is %d\n", port->bulk_in_endpointAddress);
679 	dev_dbg(&port->dev, "BulkOut endpoint is %d\n", port->bulk_out_endpointAddress);
680 	dev_dbg(&port->dev, "Interrupt endpoint is %d\n", port->interrupt_in_endpointAddress);
681 	dev_dbg(&port->dev, "port's number in the device is %d\n", mos7840_port->port_num);
682 	mos7840_port->read_urb = port->read_urb;
683 
684 	/* set up our bulk in urb */
685 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
686 		usb_fill_bulk_urb(mos7840_port->read_urb,
687 			serial->dev,
688 			usb_rcvbulkpipe(serial->dev,
689 				(port->bulk_in_endpointAddress) + 2),
690 			port->bulk_in_buffer,
691 			mos7840_port->read_urb->transfer_buffer_length,
692 			mos7840_bulk_in_callback, mos7840_port);
693 	} else {
694 		usb_fill_bulk_urb(mos7840_port->read_urb,
695 			serial->dev,
696 			usb_rcvbulkpipe(serial->dev,
697 				port->bulk_in_endpointAddress),
698 			port->bulk_in_buffer,
699 			mos7840_port->read_urb->transfer_buffer_length,
700 			mos7840_bulk_in_callback, mos7840_port);
701 	}
702 
703 	dev_dbg(&port->dev, "%s: bulkin endpoint is %d\n", __func__, port->bulk_in_endpointAddress);
704 	mos7840_port->read_urb_busy = true;
705 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
706 	if (response) {
707 		dev_err(&port->dev, "%s - Error %d submitting control urb\n",
708 			__func__, response);
709 		mos7840_port->read_urb_busy = false;
710 	}
711 
712 	/* initialize our port settings */
713 	/* Must set to enable ints! */
714 	mos7840_port->shadowMCR = MCR_MASTER_IE;
715 
716 	return 0;
717 err:
718 	for (j = 0; j < NUM_URBS; ++j) {
719 		urb = mos7840_port->write_urb_pool[j];
720 		if (!urb)
721 			continue;
722 		kfree(urb->transfer_buffer);
723 		usb_free_urb(urb);
724 	}
725 	return status;
726 }
727 
728 /*****************************************************************************
729  * mos7840_chars_in_buffer
730  *	this function is called by the tty driver when it wants to know how many
731  *	bytes of data we currently have outstanding in the port (data that has
732  *	been written, but hasn't made it out the port yet)
733  *	If successful, we return the number of bytes left to be written in the
734  *	system,
735  *	Otherwise we return zero.
736  *****************************************************************************/
737 
738 static int mos7840_chars_in_buffer(struct tty_struct *tty)
739 {
740 	struct usb_serial_port *port = tty->driver_data;
741 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
742 	int i;
743 	int chars = 0;
744 	unsigned long flags;
745 
746 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
747 	for (i = 0; i < NUM_URBS; ++i) {
748 		if (mos7840_port->busy[i]) {
749 			struct urb *urb = mos7840_port->write_urb_pool[i];
750 			chars += urb->transfer_buffer_length;
751 		}
752 	}
753 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
754 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
755 	return chars;
756 
757 }
758 
759 /*****************************************************************************
760  * mos7840_close
761  *	this function is called by the tty driver when a port is closed
762  *****************************************************************************/
763 
764 static void mos7840_close(struct usb_serial_port *port)
765 {
766 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
767 	int j;
768 	__u16 Data;
769 
770 	for (j = 0; j < NUM_URBS; ++j)
771 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
772 
773 	/* Freeing Write URBs */
774 	for (j = 0; j < NUM_URBS; ++j) {
775 		if (mos7840_port->write_urb_pool[j]) {
776 			kfree(mos7840_port->write_urb_pool[j]->transfer_buffer);
777 			usb_free_urb(mos7840_port->write_urb_pool[j]);
778 		}
779 	}
780 
781 	usb_kill_urb(mos7840_port->read_urb);
782 	mos7840_port->read_urb_busy = false;
783 
784 	Data = 0x0;
785 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
786 
787 	Data = 0x00;
788 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
789 }
790 
791 /*****************************************************************************
792  * mos7840_break
793  *	this function sends a break to the port
794  *****************************************************************************/
795 static void mos7840_break(struct tty_struct *tty, int break_state)
796 {
797 	struct usb_serial_port *port = tty->driver_data;
798 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
799 	unsigned char data;
800 
801 	if (break_state == -1)
802 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
803 	else
804 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
805 
806 	/* FIXME: no locking on shadowLCR anywhere in driver */
807 	mos7840_port->shadowLCR = data;
808 	dev_dbg(&port->dev, "%s mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
809 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
810 			     mos7840_port->shadowLCR);
811 }
812 
813 /*****************************************************************************
814  * mos7840_write_room
815  *	this function is called by the tty driver when it wants to know how many
816  *	bytes of data we can accept for a specific port.
817  *	If successful, we return the amount of room that we have for this port
818  *	Otherwise we return a negative error number.
819  *****************************************************************************/
820 
821 static int mos7840_write_room(struct tty_struct *tty)
822 {
823 	struct usb_serial_port *port = tty->driver_data;
824 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
825 	int i;
826 	int room = 0;
827 	unsigned long flags;
828 
829 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
830 	for (i = 0; i < NUM_URBS; ++i) {
831 		if (!mos7840_port->busy[i])
832 			room += URB_TRANSFER_BUFFER_SIZE;
833 	}
834 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
835 
836 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
837 	dev_dbg(&mos7840_port->port->dev, "%s - returns %d\n", __func__, room);
838 	return room;
839 
840 }
841 
842 /*****************************************************************************
843  * mos7840_write
844  *	this function is called by the tty driver when data should be written to
845  *	the port.
846  *	If successful, we return the number of bytes written, otherwise we
847  *      return a negative error number.
848  *****************************************************************************/
849 
850 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
851 			 const unsigned char *data, int count)
852 {
853 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
854 	struct usb_serial *serial = port->serial;
855 	int status;
856 	int i;
857 	int bytes_sent = 0;
858 	int transfer_size;
859 	unsigned long flags;
860 	struct urb *urb;
861 	/* __u16 Data; */
862 	const unsigned char *current_position = data;
863 
864 	/* try to find a free urb in the list */
865 	urb = NULL;
866 
867 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
868 	for (i = 0; i < NUM_URBS; ++i) {
869 		if (!mos7840_port->busy[i]) {
870 			mos7840_port->busy[i] = 1;
871 			urb = mos7840_port->write_urb_pool[i];
872 			dev_dbg(&port->dev, "URB:%d\n", i);
873 			break;
874 		}
875 	}
876 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
877 
878 	if (urb == NULL) {
879 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
880 		goto exit;
881 	}
882 
883 	if (urb->transfer_buffer == NULL) {
884 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
885 					       GFP_ATOMIC);
886 		if (!urb->transfer_buffer)
887 			goto exit;
888 	}
889 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
890 
891 	memcpy(urb->transfer_buffer, current_position, transfer_size);
892 
893 	/* fill urb with data and submit  */
894 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
895 		usb_fill_bulk_urb(urb,
896 			serial->dev,
897 			usb_sndbulkpipe(serial->dev,
898 				(port->bulk_out_endpointAddress) + 2),
899 			urb->transfer_buffer,
900 			transfer_size,
901 			mos7840_bulk_out_data_callback, mos7840_port);
902 	} else {
903 		usb_fill_bulk_urb(urb,
904 			serial->dev,
905 			usb_sndbulkpipe(serial->dev,
906 				port->bulk_out_endpointAddress),
907 			urb->transfer_buffer,
908 			transfer_size,
909 			mos7840_bulk_out_data_callback, mos7840_port);
910 	}
911 
912 	dev_dbg(&port->dev, "bulkout endpoint is %d\n", port->bulk_out_endpointAddress);
913 
914 	if (mos7840_port->has_led)
915 		mos7840_led_activity(port);
916 
917 	/* send it down the pipe */
918 	status = usb_submit_urb(urb, GFP_ATOMIC);
919 
920 	if (status) {
921 		mos7840_port->busy[i] = 0;
922 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
923 			"with status = %d\n", __func__, status);
924 		bytes_sent = status;
925 		goto exit;
926 	}
927 	bytes_sent = transfer_size;
928 	port->icount.tx += transfer_size;
929 	dev_dbg(&port->dev, "icount.tx is %d:\n", port->icount.tx);
930 exit:
931 	return bytes_sent;
932 
933 }
934 
935 /*****************************************************************************
936  * mos7840_throttle
937  *	this function is called by the tty driver when it wants to stop the data
938  *	being read from the port.
939  *****************************************************************************/
940 
941 static void mos7840_throttle(struct tty_struct *tty)
942 {
943 	struct usb_serial_port *port = tty->driver_data;
944 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
945 	int status;
946 
947 	/* if we are implementing XON/XOFF, send the stop character */
948 	if (I_IXOFF(tty)) {
949 		unsigned char stop_char = STOP_CHAR(tty);
950 		status = mos7840_write(tty, port, &stop_char, 1);
951 		if (status <= 0)
952 			return;
953 	}
954 	/* if we are implementing RTS/CTS, toggle that line */
955 	if (C_CRTSCTS(tty)) {
956 		mos7840_port->shadowMCR &= ~MCR_RTS;
957 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
958 					 mos7840_port->shadowMCR);
959 		if (status < 0)
960 			return;
961 	}
962 }
963 
964 /*****************************************************************************
965  * mos7840_unthrottle
966  *	this function is called by the tty driver when it wants to resume
967  *	the data being read from the port (called after mos7840_throttle is
968  *	called)
969  *****************************************************************************/
970 static void mos7840_unthrottle(struct tty_struct *tty)
971 {
972 	struct usb_serial_port *port = tty->driver_data;
973 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
974 	int status;
975 
976 	/* if we are implementing XON/XOFF, send the start character */
977 	if (I_IXOFF(tty)) {
978 		unsigned char start_char = START_CHAR(tty);
979 		status = mos7840_write(tty, port, &start_char, 1);
980 		if (status <= 0)
981 			return;
982 	}
983 
984 	/* if we are implementing RTS/CTS, toggle that line */
985 	if (C_CRTSCTS(tty)) {
986 		mos7840_port->shadowMCR |= MCR_RTS;
987 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
988 					 mos7840_port->shadowMCR);
989 		if (status < 0)
990 			return;
991 	}
992 }
993 
994 static int mos7840_tiocmget(struct tty_struct *tty)
995 {
996 	struct usb_serial_port *port = tty->driver_data;
997 	unsigned int result;
998 	__u16 msr;
999 	__u16 mcr;
1000 	int status;
1001 
1002 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
1003 	if (status < 0)
1004 		return -EIO;
1005 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1006 	if (status < 0)
1007 		return -EIO;
1008 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1009 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1010 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1011 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1012 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1013 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1014 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1015 
1016 	dev_dbg(&port->dev, "%s - 0x%04X\n", __func__, result);
1017 
1018 	return result;
1019 }
1020 
1021 static int mos7840_tiocmset(struct tty_struct *tty,
1022 			    unsigned int set, unsigned int clear)
1023 {
1024 	struct usb_serial_port *port = tty->driver_data;
1025 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1026 	unsigned int mcr;
1027 	int status;
1028 
1029 	/* FIXME: What locks the port registers ? */
1030 	mcr = mos7840_port->shadowMCR;
1031 	if (clear & TIOCM_RTS)
1032 		mcr &= ~MCR_RTS;
1033 	if (clear & TIOCM_DTR)
1034 		mcr &= ~MCR_DTR;
1035 	if (clear & TIOCM_LOOP)
1036 		mcr &= ~MCR_LOOPBACK;
1037 
1038 	if (set & TIOCM_RTS)
1039 		mcr |= MCR_RTS;
1040 	if (set & TIOCM_DTR)
1041 		mcr |= MCR_DTR;
1042 	if (set & TIOCM_LOOP)
1043 		mcr |= MCR_LOOPBACK;
1044 
1045 	mos7840_port->shadowMCR = mcr;
1046 
1047 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1048 	if (status < 0) {
1049 		dev_dbg(&port->dev, "setting MODEM_CONTROL_REGISTER Failed\n");
1050 		return status;
1051 	}
1052 
1053 	return 0;
1054 }
1055 
1056 /*****************************************************************************
1057  * mos7840_calc_baud_rate_divisor
1058  *	this function calculates the proper baud rate divisor for the specified
1059  *	baud rate.
1060  *****************************************************************************/
1061 static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
1062 					  int baudRate, int *divisor,
1063 					  __u16 *clk_sel_val)
1064 {
1065 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudRate);
1066 
1067 	if (baudRate <= 115200) {
1068 		*divisor = 115200 / baudRate;
1069 		*clk_sel_val = 0x0;
1070 	}
1071 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1072 		*divisor = 230400 / baudRate;
1073 		*clk_sel_val = 0x10;
1074 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1075 		*divisor = 403200 / baudRate;
1076 		*clk_sel_val = 0x20;
1077 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1078 		*divisor = 460800 / baudRate;
1079 		*clk_sel_val = 0x30;
1080 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1081 		*divisor = 806400 / baudRate;
1082 		*clk_sel_val = 0x40;
1083 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1084 		*divisor = 921600 / baudRate;
1085 		*clk_sel_val = 0x50;
1086 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1087 		*divisor = 1572864 / baudRate;
1088 		*clk_sel_val = 0x60;
1089 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1090 		*divisor = 3145728 / baudRate;
1091 		*clk_sel_val = 0x70;
1092 	}
1093 	return 0;
1094 }
1095 
1096 /*****************************************************************************
1097  * mos7840_send_cmd_write_baud_rate
1098  *	this function sends the proper command to change the baud rate of the
1099  *	specified port.
1100  *****************************************************************************/
1101 
1102 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1103 					    int baudRate)
1104 {
1105 	struct usb_serial_port *port = mos7840_port->port;
1106 	int divisor = 0;
1107 	int status;
1108 	__u16 Data;
1109 	__u16 clk_sel_val;
1110 
1111 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudRate);
1112 	/* reset clk_uart_sel in spregOffset */
1113 	if (baudRate > 115200) {
1114 #ifdef HW_flow_control
1115 		/* NOTE: need to see the pther register to modify */
1116 		/* setting h/w flow control bit to 1 */
1117 		Data = 0x2b;
1118 		mos7840_port->shadowMCR = Data;
1119 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1120 									Data);
1121 		if (status < 0) {
1122 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1123 			return -1;
1124 		}
1125 #endif
1126 
1127 	} else {
1128 #ifdef HW_flow_control
1129 		/* setting h/w flow control bit to 0 */
1130 		Data = 0xb;
1131 		mos7840_port->shadowMCR = Data;
1132 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1133 									Data);
1134 		if (status < 0) {
1135 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1136 			return -1;
1137 		}
1138 #endif
1139 
1140 	}
1141 
1142 	if (1) {		/* baudRate <= 115200) */
1143 		clk_sel_val = 0x0;
1144 		Data = 0x0;
1145 		status = mos7840_calc_baud_rate_divisor(port, baudRate, &divisor,
1146 						   &clk_sel_val);
1147 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1148 								 &Data);
1149 		if (status < 0) {
1150 			dev_dbg(&port->dev, "reading spreg failed in set_serial_baud\n");
1151 			return -1;
1152 		}
1153 		Data = (Data & 0x8f) | clk_sel_val;
1154 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1155 								Data);
1156 		if (status < 0) {
1157 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1158 			return -1;
1159 		}
1160 		/* Calculate the Divisor */
1161 
1162 		if (status) {
1163 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1164 			return status;
1165 		}
1166 		/* Enable access to divisor latch */
1167 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1168 		mos7840_port->shadowLCR = Data;
1169 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1170 
1171 		/* Write the divisor */
1172 		Data = (unsigned char)(divisor & 0xff);
1173 		dev_dbg(&port->dev, "set_serial_baud Value to write DLL is %x\n", Data);
1174 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1175 
1176 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1177 		dev_dbg(&port->dev, "set_serial_baud Value to write DLM is %x\n", Data);
1178 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1179 
1180 		/* Disable access to divisor latch */
1181 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1182 		mos7840_port->shadowLCR = Data;
1183 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1184 
1185 	}
1186 	return status;
1187 }
1188 
1189 /*****************************************************************************
1190  * mos7840_change_port_settings
1191  *	This routine is called to set the UART on the device to match
1192  *      the specified new settings.
1193  *****************************************************************************/
1194 
1195 static void mos7840_change_port_settings(struct tty_struct *tty,
1196 	struct moschip_port *mos7840_port, struct ktermios *old_termios)
1197 {
1198 	struct usb_serial_port *port = mos7840_port->port;
1199 	int baud;
1200 	unsigned cflag;
1201 	__u8 lData;
1202 	__u8 lParity;
1203 	__u8 lStop;
1204 	int status;
1205 	__u16 Data;
1206 
1207 	lData = LCR_BITS_8;
1208 	lStop = LCR_STOP_1;
1209 	lParity = LCR_PAR_NONE;
1210 
1211 	cflag = tty->termios.c_cflag;
1212 
1213 	/* Change the number of bits */
1214 	switch (cflag & CSIZE) {
1215 	case CS5:
1216 		lData = LCR_BITS_5;
1217 		break;
1218 
1219 	case CS6:
1220 		lData = LCR_BITS_6;
1221 		break;
1222 
1223 	case CS7:
1224 		lData = LCR_BITS_7;
1225 		break;
1226 
1227 	default:
1228 	case CS8:
1229 		lData = LCR_BITS_8;
1230 		break;
1231 	}
1232 
1233 	/* Change the Parity bit */
1234 	if (cflag & PARENB) {
1235 		if (cflag & PARODD) {
1236 			lParity = LCR_PAR_ODD;
1237 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1238 		} else {
1239 			lParity = LCR_PAR_EVEN;
1240 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1241 		}
1242 
1243 	} else {
1244 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1245 	}
1246 
1247 	if (cflag & CMSPAR)
1248 		lParity = lParity | 0x20;
1249 
1250 	/* Change the Stop bit */
1251 	if (cflag & CSTOPB) {
1252 		lStop = LCR_STOP_2;
1253 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1254 	} else {
1255 		lStop = LCR_STOP_1;
1256 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1257 	}
1258 
1259 	/* Update the LCR with the correct value */
1260 	mos7840_port->shadowLCR &=
1261 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1262 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1263 
1264 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is %x\n", __func__,
1265 		mos7840_port->shadowLCR);
1266 	/* Disable Interrupts */
1267 	Data = 0x00;
1268 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1269 
1270 	Data = 0x00;
1271 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1272 
1273 	Data = 0xcf;
1274 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1275 
1276 	/* Send the updated LCR value to the mos7840 */
1277 	Data = mos7840_port->shadowLCR;
1278 
1279 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1280 
1281 	Data = 0x00b;
1282 	mos7840_port->shadowMCR = Data;
1283 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1284 	Data = 0x00b;
1285 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1286 
1287 	/* set up the MCR register and send it to the mos7840 */
1288 
1289 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1290 	if (cflag & CBAUD)
1291 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
1292 
1293 	if (cflag & CRTSCTS)
1294 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
1295 	else
1296 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
1297 
1298 	Data = mos7840_port->shadowMCR;
1299 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1300 
1301 	/* Determine divisor based on baud rate */
1302 	baud = tty_get_baud_rate(tty);
1303 
1304 	if (!baud) {
1305 		/* pick a default, any default... */
1306 		dev_dbg(&port->dev, "%s", "Picked default baud...\n");
1307 		baud = 9600;
1308 	}
1309 
1310 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1311 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
1312 
1313 	/* Enable Interrupts */
1314 	Data = 0x0c;
1315 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1316 
1317 	if (!mos7840_port->read_urb_busy) {
1318 		mos7840_port->read_urb_busy = true;
1319 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1320 		if (status) {
1321 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1322 			    status);
1323 			mos7840_port->read_urb_busy = false;
1324 		}
1325 	}
1326 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
1327 		mos7840_port->shadowLCR);
1328 }
1329 
1330 /*****************************************************************************
1331  * mos7840_set_termios
1332  *	this function is called by the tty driver when it wants to change
1333  *	the termios structure
1334  *****************************************************************************/
1335 
1336 static void mos7840_set_termios(struct tty_struct *tty,
1337 				struct usb_serial_port *port,
1338 				struct ktermios *old_termios)
1339 {
1340 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1341 	int status;
1342 
1343 	/* change the port settings to the new ones specified */
1344 
1345 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
1346 
1347 	if (!mos7840_port->read_urb_busy) {
1348 		mos7840_port->read_urb_busy = true;
1349 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1350 		if (status) {
1351 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1352 			    status);
1353 			mos7840_port->read_urb_busy = false;
1354 		}
1355 	}
1356 }
1357 
1358 /*****************************************************************************
1359  * mos7840_get_lsr_info - get line status register info
1360  *
1361  * Purpose: Let user call ioctl() to get info when the UART physically
1362  * 	    is emptied.  On bus types like RS485, the transmitter must
1363  * 	    release the bus after transmitting. This must be done when
1364  * 	    the transmit shift register is empty, not be done when the
1365  * 	    transmit holding register is empty.  This functionality
1366  * 	    allows an RS485 driver to be written in user space.
1367  *****************************************************************************/
1368 
1369 static int mos7840_get_lsr_info(struct tty_struct *tty,
1370 				unsigned int __user *value)
1371 {
1372 	int count;
1373 	unsigned int result = 0;
1374 
1375 	count = mos7840_chars_in_buffer(tty);
1376 	if (count == 0)
1377 		result = TIOCSER_TEMT;
1378 
1379 	if (copy_to_user(value, &result, sizeof(int)))
1380 		return -EFAULT;
1381 	return 0;
1382 }
1383 
1384 /*****************************************************************************
1385  * mos7840_get_serial_info
1386  *      function to get information about serial port
1387  *****************************************************************************/
1388 
1389 static int mos7840_get_serial_info(struct tty_struct *tty,
1390 				   struct serial_struct *ss)
1391 {
1392 	struct usb_serial_port *port = tty->driver_data;
1393 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1394 
1395 	ss->type = PORT_16550A;
1396 	ss->line = mos7840_port->port->minor;
1397 	ss->port = mos7840_port->port->port_number;
1398 	ss->irq = 0;
1399 	ss->xmit_fifo_size = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1400 	ss->baud_base = 9600;
1401 	ss->close_delay = 5 * HZ;
1402 	ss->closing_wait = 30 * HZ;
1403 	return 0;
1404 }
1405 
1406 /*****************************************************************************
1407  * SerialIoctl
1408  *	this function handles any ioctl calls to the driver
1409  *****************************************************************************/
1410 
1411 static int mos7840_ioctl(struct tty_struct *tty,
1412 			 unsigned int cmd, unsigned long arg)
1413 {
1414 	struct usb_serial_port *port = tty->driver_data;
1415 	void __user *argp = (void __user *)arg;
1416 
1417 	switch (cmd) {
1418 		/* return number of bytes available */
1419 
1420 	case TIOCSERGETLSR:
1421 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1422 		return mos7840_get_lsr_info(tty, argp);
1423 
1424 	default:
1425 		break;
1426 	}
1427 	return -ENOIOCTLCMD;
1428 }
1429 
1430 /*
1431  * Check if GPO (pin 42) is connected to GPI (pin 33) as recommended by ASIX
1432  * for MCS7810 by bit-banging a 16-bit word.
1433  *
1434  * Note that GPO is really RTS of the third port so this will toggle RTS of
1435  * port two or three on two- and four-port devices.
1436  */
1437 static int mos7810_check(struct usb_serial *serial)
1438 {
1439 	int i, pass_count = 0;
1440 	u8 *buf;
1441 	__u16 data = 0, mcr_data = 0;
1442 	__u16 test_pattern = 0x55AA;
1443 	int res;
1444 
1445 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1446 	if (!buf)
1447 		return 0;	/* failed to identify 7810 */
1448 
1449 	/* Store MCR setting */
1450 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1451 		MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
1452 		buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1453 	if (res == VENDOR_READ_LENGTH)
1454 		mcr_data = *buf;
1455 
1456 	for (i = 0; i < 16; i++) {
1457 		/* Send the 1-bit test pattern out to MCS7810 test pin */
1458 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1459 			MCS_WRREQ, MCS_WR_RTYPE,
1460 			(0x0300 | (((test_pattern >> i) & 0x0001) << 1)),
1461 			MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
1462 
1463 		/* Read the test pattern back */
1464 		res = usb_control_msg(serial->dev,
1465 				usb_rcvctrlpipe(serial->dev, 0), MCS_RDREQ,
1466 				MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1467 				VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1468 		if (res == VENDOR_READ_LENGTH)
1469 			data = *buf;
1470 
1471 		/* If this is a MCS7810 device, both test patterns must match */
1472 		if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
1473 			break;
1474 
1475 		pass_count++;
1476 	}
1477 
1478 	/* Restore MCR setting */
1479 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), MCS_WRREQ,
1480 		MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
1481 		0, MOS_WDR_TIMEOUT);
1482 
1483 	kfree(buf);
1484 
1485 	if (pass_count == 16)
1486 		return 1;
1487 
1488 	return 0;
1489 }
1490 
1491 static int mos7840_probe(struct usb_serial *serial,
1492 				const struct usb_device_id *id)
1493 {
1494 	unsigned long device_flags = id->driver_info;
1495 	u8 *buf;
1496 
1497 	/* Skip device-type detection if we already have device flags. */
1498 	if (device_flags)
1499 		goto out;
1500 
1501 	buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
1502 	if (!buf)
1503 		return -ENOMEM;
1504 
1505 	usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1506 			MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
1507 			VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
1508 
1509 	/* For a MCS7840 device GPIO0 must be set to 1 */
1510 	if (buf[0] & 0x01)
1511 		device_flags = MCS_PORTS(4);
1512 	else if (mos7810_check(serial))
1513 		device_flags = MCS_PORTS(1) | MCS_LED;
1514 	else
1515 		device_flags = MCS_PORTS(2);
1516 
1517 	kfree(buf);
1518 out:
1519 	usb_set_serial_data(serial, (void *)device_flags);
1520 
1521 	return 0;
1522 }
1523 
1524 static int mos7840_calc_num_ports(struct usb_serial *serial,
1525 					struct usb_serial_endpoints *epds)
1526 {
1527 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1528 	int num_ports = MCS_PORTS(device_flags);
1529 
1530 	if (num_ports == 0 || num_ports > 4)
1531 		return -ENODEV;
1532 
1533 	if (epds->num_bulk_in < num_ports || epds->num_bulk_out < num_ports) {
1534 		dev_err(&serial->interface->dev, "missing endpoints\n");
1535 		return -ENODEV;
1536 	}
1537 
1538 	return num_ports;
1539 }
1540 
1541 static int mos7840_attach(struct usb_serial *serial)
1542 {
1543 	struct device *dev = &serial->interface->dev;
1544 	int status;
1545 	u16 val;
1546 
1547 	/* Zero Length flag enable */
1548 	val = 0x0f;
1549 	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, val);
1550 	if (status < 0)
1551 		dev_dbg(dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
1552 	else
1553 		dev_dbg(dev, "ZLP_REG5 Writing success status%d\n", status);
1554 
1555 	return status;
1556 }
1557 
1558 static int mos7840_port_probe(struct usb_serial_port *port)
1559 {
1560 	struct usb_serial *serial = port->serial;
1561 	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
1562 	struct moschip_port *mos7840_port;
1563 	int status;
1564 	int pnum;
1565 	__u16 Data;
1566 
1567 	/* we set up the pointers to the endpoints in the mos7840_open *
1568 	 * function, as the structures aren't created yet.             */
1569 
1570 	pnum = port->port_number;
1571 
1572 	dev_dbg(&port->dev, "mos7840_startup: configuring port %d\n", pnum);
1573 	mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
1574 	if (!mos7840_port)
1575 		return -ENOMEM;
1576 
1577 	/* Initialize all port interrupt end point to port 0 int
1578 	 * endpoint. Our device has only one interrupt end point
1579 	 * common to all port */
1580 
1581 	mos7840_port->port = port;
1582 	spin_lock_init(&mos7840_port->pool_lock);
1583 
1584 	/* minor is not initialised until later by
1585 	 * usb-serial.c:get_free_serial() and cannot therefore be used
1586 	 * to index device instances */
1587 	mos7840_port->port_num = pnum + 1;
1588 	dev_dbg(&port->dev, "port->minor = %d\n", port->minor);
1589 	dev_dbg(&port->dev, "mos7840_port->port_num = %d\n", mos7840_port->port_num);
1590 
1591 	if (mos7840_port->port_num == 1) {
1592 		mos7840_port->SpRegOffset = 0x0;
1593 		mos7840_port->ControlRegOffset = 0x1;
1594 		mos7840_port->DcrRegOffset = 0x4;
1595 	} else {
1596 		u8 phy_num = mos7840_port->port_num;
1597 
1598 		/* Port 2 in the 2-port case uses registers of port 3 */
1599 		if (serial->num_ports == 2)
1600 			phy_num = 3;
1601 
1602 		mos7840_port->SpRegOffset = 0x8 + 2 * (phy_num - 2);
1603 		mos7840_port->ControlRegOffset = 0x9 + 2 * (phy_num - 2);
1604 		mos7840_port->DcrRegOffset = 0x16 + 3 * (phy_num - 2);
1605 	}
1606 	mos7840_dump_serial_port(port, mos7840_port);
1607 	usb_set_serial_port_data(port, mos7840_port);
1608 
1609 	/* enable rx_disable bit in control register */
1610 	status = mos7840_get_reg_sync(port,
1611 			mos7840_port->ControlRegOffset, &Data);
1612 	if (status < 0) {
1613 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
1614 		goto error;
1615 	} else
1616 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
1617 	Data |= 0x08;	/* setting driver done bit */
1618 	Data |= 0x04;	/* sp1_bit to have cts change reflect in
1619 			   modem status reg */
1620 
1621 	/* Data |= 0x20; //rx_disable bit */
1622 	status = mos7840_set_reg_sync(port,
1623 			mos7840_port->ControlRegOffset, Data);
1624 	if (status < 0) {
1625 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
1626 		goto error;
1627 	} else
1628 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
1629 
1630 	/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
1631 	   and 0x24 in DCR3 */
1632 	Data = 0x01;
1633 	status = mos7840_set_reg_sync(port,
1634 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
1635 	if (status < 0) {
1636 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
1637 		goto error;
1638 	} else
1639 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
1640 
1641 	Data = 0x05;
1642 	status = mos7840_set_reg_sync(port,
1643 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
1644 	if (status < 0) {
1645 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
1646 		goto error;
1647 	} else
1648 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
1649 
1650 	Data = 0x24;
1651 	status = mos7840_set_reg_sync(port,
1652 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
1653 	if (status < 0) {
1654 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
1655 		goto error;
1656 	} else
1657 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
1658 
1659 	/* write values in clkstart0x0 and clkmulti 0x20 */
1660 	Data = 0x0;
1661 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
1662 	if (status < 0) {
1663 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
1664 		goto error;
1665 	} else
1666 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
1667 
1668 	Data = 0x20;
1669 	status = mos7840_set_reg_sync(port, CLK_MULTI_REGISTER, Data);
1670 	if (status < 0) {
1671 		dev_dbg(&port->dev, "Writing CLK_MULTI_REGISTER failed status-0x%x\n", status);
1672 		goto error;
1673 	} else
1674 		dev_dbg(&port->dev, "CLK_MULTI_REGISTER Writing success status%d\n", status);
1675 
1676 	/* write value 0x0 to scratchpad register */
1677 	Data = 0x00;
1678 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
1679 	if (status < 0) {
1680 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
1681 		goto error;
1682 	} else
1683 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
1684 
1685 	/* Zero Length flag register */
1686 	if ((mos7840_port->port_num != 1) && (serial->num_ports == 2)) {
1687 		Data = 0xff;
1688 		status = mos7840_set_reg_sync(port,
1689 				(__u16) (ZLP_REG1 +
1690 					((__u16)mos7840_port->port_num)), Data);
1691 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1692 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
1693 		if (status < 0) {
1694 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
1695 			goto error;
1696 		} else
1697 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
1698 	} else {
1699 		Data = 0xff;
1700 		status = mos7840_set_reg_sync(port,
1701 				(__u16) (ZLP_REG1 +
1702 					((__u16)mos7840_port->port_num) - 0x1), Data);
1703 		dev_dbg(&port->dev, "ZLIP offset %x\n",
1704 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
1705 		if (status < 0) {
1706 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
1707 			goto error;
1708 		} else
1709 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
1710 
1711 	}
1712 
1713 	mos7840_port->has_led = device_flags & MCS_LED;
1714 
1715 	/* Initialize LED timers */
1716 	if (mos7840_port->has_led) {
1717 		mos7840_port->led_urb = usb_alloc_urb(0, GFP_KERNEL);
1718 		mos7840_port->led_dr = kmalloc(sizeof(*mos7840_port->led_dr),
1719 								GFP_KERNEL);
1720 		if (!mos7840_port->led_urb || !mos7840_port->led_dr) {
1721 			status = -ENOMEM;
1722 			goto error;
1723 		}
1724 
1725 		timer_setup(&mos7840_port->led_timer1, mos7840_led_off, 0);
1726 		mos7840_port->led_timer1.expires =
1727 			jiffies + msecs_to_jiffies(LED_ON_MS);
1728 		timer_setup(&mos7840_port->led_timer2, mos7840_led_flag_off,
1729 			    0);
1730 		mos7840_port->led_timer2.expires =
1731 			jiffies + msecs_to_jiffies(LED_OFF_MS);
1732 
1733 		/* Turn off LED */
1734 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1735 	}
1736 
1737 	return 0;
1738 error:
1739 	kfree(mos7840_port->led_dr);
1740 	usb_free_urb(mos7840_port->led_urb);
1741 	kfree(mos7840_port);
1742 
1743 	return status;
1744 }
1745 
1746 static int mos7840_port_remove(struct usb_serial_port *port)
1747 {
1748 	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
1749 
1750 	if (mos7840_port->has_led) {
1751 		/* Turn off LED */
1752 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
1753 
1754 		del_timer_sync(&mos7840_port->led_timer1);
1755 		del_timer_sync(&mos7840_port->led_timer2);
1756 
1757 		usb_kill_urb(mos7840_port->led_urb);
1758 		usb_free_urb(mos7840_port->led_urb);
1759 		kfree(mos7840_port->led_dr);
1760 	}
1761 
1762 	kfree(mos7840_port);
1763 
1764 	return 0;
1765 }
1766 
1767 static struct usb_serial_driver moschip7840_4port_device = {
1768 	.driver = {
1769 		   .owner = THIS_MODULE,
1770 		   .name = "mos7840",
1771 		   },
1772 	.description = DRIVER_DESC,
1773 	.id_table = id_table,
1774 	.num_interrupt_in = 1,
1775 	.open = mos7840_open,
1776 	.close = mos7840_close,
1777 	.write = mos7840_write,
1778 	.write_room = mos7840_write_room,
1779 	.chars_in_buffer = mos7840_chars_in_buffer,
1780 	.throttle = mos7840_throttle,
1781 	.unthrottle = mos7840_unthrottle,
1782 	.calc_num_ports = mos7840_calc_num_ports,
1783 	.probe = mos7840_probe,
1784 	.attach = mos7840_attach,
1785 	.ioctl = mos7840_ioctl,
1786 	.get_serial = mos7840_get_serial_info,
1787 	.set_termios = mos7840_set_termios,
1788 	.break_ctl = mos7840_break,
1789 	.tiocmget = mos7840_tiocmget,
1790 	.tiocmset = mos7840_tiocmset,
1791 	.get_icount = usb_serial_generic_get_icount,
1792 	.port_probe = mos7840_port_probe,
1793 	.port_remove = mos7840_port_remove,
1794 	.read_bulk_callback = mos7840_bulk_in_callback,
1795 };
1796 
1797 static struct usb_serial_driver * const serial_drivers[] = {
1798 	&moschip7840_4port_device, NULL
1799 };
1800 
1801 module_usb_serial_driver(serial_drivers, id_table);
1802 
1803 MODULE_DESCRIPTION(DRIVER_DESC);
1804 MODULE_LICENSE("GPL");
1805