xref: /openbmc/linux/drivers/usb/serial/mos7840.c (revision 7b6d864b)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License as published by
4  * the Free Software Foundation; either version 2 of the License, or
5  * (at your option) any later version.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program; if not, write to the Free Software
14  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
15  *
16  * Clean ups from Moschip version and a few ioctl implementations by:
17  *	Paul B Schroeder <pschroeder "at" uplogix "dot" com>
18  *
19  * Originally based on drivers/usb/serial/io_edgeport.c which is:
20  *      Copyright (C) 2000 Inside Out Networks, All rights reserved.
21  *      Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
22  *
23  */
24 
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/tty.h>
30 #include <linux/tty_driver.h>
31 #include <linux/tty_flip.h>
32 #include <linux/module.h>
33 #include <linux/serial.h>
34 #include <linux/usb.h>
35 #include <linux/usb/serial.h>
36 #include <linux/uaccess.h>
37 
38 #define DRIVER_DESC "Moschip 7840/7820 USB Serial Driver"
39 
40 /*
41  * 16C50 UART register defines
42  */
43 
44 #define LCR_BITS_5             0x00	/* 5 bits/char */
45 #define LCR_BITS_6             0x01	/* 6 bits/char */
46 #define LCR_BITS_7             0x02	/* 7 bits/char */
47 #define LCR_BITS_8             0x03	/* 8 bits/char */
48 #define LCR_BITS_MASK          0x03	/* Mask for bits/char field */
49 
50 #define LCR_STOP_1             0x00	/* 1 stop bit */
51 #define LCR_STOP_1_5           0x04	/* 1.5 stop bits (if 5   bits/char) */
52 #define LCR_STOP_2             0x04	/* 2 stop bits   (if 6-8 bits/char) */
53 #define LCR_STOP_MASK          0x04	/* Mask for stop bits field */
54 
55 #define LCR_PAR_NONE           0x00	/* No parity */
56 #define LCR_PAR_ODD            0x08	/* Odd parity */
57 #define LCR_PAR_EVEN           0x18	/* Even parity */
58 #define LCR_PAR_MARK           0x28	/* Force parity bit to 1 */
59 #define LCR_PAR_SPACE          0x38	/* Force parity bit to 0 */
60 #define LCR_PAR_MASK           0x38	/* Mask for parity field */
61 
62 #define LCR_SET_BREAK          0x40	/* Set Break condition */
63 #define LCR_DL_ENABLE          0x80	/* Enable access to divisor latch */
64 
65 #define MCR_DTR                0x01	/* Assert DTR */
66 #define MCR_RTS                0x02	/* Assert RTS */
67 #define MCR_OUT1               0x04	/* Loopback only: Sets state of RI */
68 #define MCR_MASTER_IE          0x08	/* Enable interrupt outputs */
69 #define MCR_LOOPBACK           0x10	/* Set internal (digital) loopback mode */
70 #define MCR_XON_ANY            0x20	/* Enable any char to exit XOFF mode */
71 
72 #define MOS7840_MSR_CTS        0x10	/* Current state of CTS */
73 #define MOS7840_MSR_DSR        0x20	/* Current state of DSR */
74 #define MOS7840_MSR_RI         0x40	/* Current state of RI */
75 #define MOS7840_MSR_CD         0x80	/* Current state of CD */
76 
77 /*
78  * Defines used for sending commands to port
79  */
80 
81 #define MOS_WDR_TIMEOUT		5000	/* default urb timeout */
82 
83 #define MOS_PORT1       0x0200
84 #define MOS_PORT2       0x0300
85 #define MOS_VENREG      0x0000
86 #define MOS_MAX_PORT	0x02
87 #define MOS_WRITE       0x0E
88 #define MOS_READ        0x0D
89 
90 /* Requests */
91 #define MCS_RD_RTYPE    0xC0
92 #define MCS_WR_RTYPE    0x40
93 #define MCS_RDREQ       0x0D
94 #define MCS_WRREQ       0x0E
95 #define MCS_CTRL_TIMEOUT        500
96 #define VENDOR_READ_LENGTH      (0x01)
97 
98 #define MAX_NAME_LEN    64
99 
100 #define ZLP_REG1  0x3A		/* Zero_Flag_Reg1    58 */
101 #define ZLP_REG5  0x3E		/* Zero_Flag_Reg5    62 */
102 
103 /* For higher baud Rates use TIOCEXBAUD */
104 #define TIOCEXBAUD     0x5462
105 
106 /* vendor id and device id defines */
107 
108 /* The native mos7840/7820 component */
109 #define USB_VENDOR_ID_MOSCHIP           0x9710
110 #define MOSCHIP_DEVICE_ID_7840          0x7840
111 #define MOSCHIP_DEVICE_ID_7820          0x7820
112 #define MOSCHIP_DEVICE_ID_7810          0x7810
113 /* The native component can have its vendor/device id's overridden
114  * in vendor-specific implementations.  Such devices can be handled
115  * by making a change here, in id_table.
116  */
117 #define USB_VENDOR_ID_BANDB              0x0856
118 #define BANDB_DEVICE_ID_USO9ML2_2        0xAC22
119 #define BANDB_DEVICE_ID_USO9ML2_2P       0xBC00
120 #define BANDB_DEVICE_ID_USO9ML2_4        0xAC24
121 #define BANDB_DEVICE_ID_USO9ML2_4P       0xBC01
122 #define BANDB_DEVICE_ID_US9ML2_2         0xAC29
123 #define BANDB_DEVICE_ID_US9ML2_4         0xAC30
124 #define BANDB_DEVICE_ID_USPTL4_2         0xAC31
125 #define BANDB_DEVICE_ID_USPTL4_4         0xAC32
126 #define BANDB_DEVICE_ID_USOPTL4_2        0xAC42
127 #define BANDB_DEVICE_ID_USOPTL4_2P       0xBC02
128 #define BANDB_DEVICE_ID_USOPTL4_4        0xAC44
129 #define BANDB_DEVICE_ID_USOPTL4_4P       0xBC03
130 #define BANDB_DEVICE_ID_USOPTL2_4        0xAC24
131 
132 /* This driver also supports
133  * ATEN UC2324 device using Moschip MCS7840
134  * ATEN UC2322 device using Moschip MCS7820
135  */
136 #define USB_VENDOR_ID_ATENINTL		0x0557
137 #define ATENINTL_DEVICE_ID_UC2324	0x2011
138 #define ATENINTL_DEVICE_ID_UC2322	0x7820
139 
140 /* Interrupt Routine Defines    */
141 
142 #define SERIAL_IIR_RLS      0x06
143 #define SERIAL_IIR_MS       0x00
144 
145 /*
146  *  Emulation of the bit mask on the LINE STATUS REGISTER.
147  */
148 #define SERIAL_LSR_DR       0x0001
149 #define SERIAL_LSR_OE       0x0002
150 #define SERIAL_LSR_PE       0x0004
151 #define SERIAL_LSR_FE       0x0008
152 #define SERIAL_LSR_BI       0x0010
153 
154 #define MOS_MSR_DELTA_CTS   0x10
155 #define MOS_MSR_DELTA_DSR   0x20
156 #define MOS_MSR_DELTA_RI    0x40
157 #define MOS_MSR_DELTA_CD    0x80
158 
159 /* Serial Port register Address */
160 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
161 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
162 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
163 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
164 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
165 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
166 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
167 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
168 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
169 
170 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
171 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
172 #define GPIO_REGISTER              ((__u16)(0x07))
173 
174 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
175 
176 /*
177  * URB POOL related defines
178  */
179 #define NUM_URBS                        16	/* URB Count */
180 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
181 
182 /* LED on/off milliseconds*/
183 #define LED_ON_MS	500
184 #define LED_OFF_MS	500
185 
186 static int device_type;
187 
188 static const struct usb_device_id id_table[] = {
189 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
190 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
191 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7810)},
192 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2)},
193 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P)},
194 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4)},
195 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P)},
196 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2)},
197 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4)},
198 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2)},
199 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4)},
200 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2)},
201 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P)},
202 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4)},
203 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P)},
204 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL2_4)},
205 	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2324)},
206 	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2322)},
207 	{}			/* terminating entry */
208 };
209 MODULE_DEVICE_TABLE(usb, id_table);
210 
211 /* This structure holds all of the local port information */
212 
213 struct moschip_port {
214 	int port_num;		/*Actual port number in the device(1,2,etc) */
215 	struct urb *write_urb;	/* write URB for this port */
216 	struct urb *read_urb;	/* read URB for this port */
217 	__u8 shadowLCR;		/* last LCR value received */
218 	__u8 shadowMCR;		/* last MCR value received */
219 	char open;
220 	char open_ports;
221 	wait_queue_head_t wait_chase;	/* for handling sleeping while waiting for chase to finish */
222 	struct usb_serial_port *port;	/* loop back to the owner of this object */
223 
224 	/* Offsets */
225 	__u8 SpRegOffset;
226 	__u8 ControlRegOffset;
227 	__u8 DcrRegOffset;
228 	/* for processing control URBS in interrupt context */
229 	struct urb *control_urb;
230 	struct usb_ctrlrequest *dr;
231 	char *ctrl_buf;
232 	int MsrLsr;
233 
234 	spinlock_t pool_lock;
235 	struct urb *write_urb_pool[NUM_URBS];
236 	char busy[NUM_URBS];
237 	bool read_urb_busy;
238 
239 	/* For device(s) with LED indicator */
240 	bool has_led;
241 	bool led_flag;
242 	struct timer_list led_timer1;	/* Timer for LED on */
243 	struct timer_list led_timer2;	/* Timer for LED off */
244 };
245 
246 /*
247  * mos7840_set_reg_sync
248  * 	To set the Control register by calling usb_fill_control_urb function
249  *	by passing usb_sndctrlpipe function as parameter.
250  */
251 
252 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
253 				__u16 val)
254 {
255 	struct usb_device *dev = port->serial->dev;
256 	val = val & 0x00ff;
257 	dev_dbg(&port->dev, "mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
258 
259 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
260 			       MCS_WR_RTYPE, val, reg, NULL, 0,
261 			       MOS_WDR_TIMEOUT);
262 }
263 
264 /*
265  * mos7840_get_reg_sync
266  * 	To set the Uart register by calling usb_fill_control_urb function by
267  *	passing usb_rcvctrlpipe function as parameter.
268  */
269 
270 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
271 				__u16 *val)
272 {
273 	struct usb_device *dev = port->serial->dev;
274 	int ret = 0;
275 	u8 *buf;
276 
277 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
278 	if (!buf)
279 		return -ENOMEM;
280 
281 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
282 			      MCS_RD_RTYPE, 0, reg, buf, VENDOR_READ_LENGTH,
283 			      MOS_WDR_TIMEOUT);
284 	*val = buf[0];
285 	dev_dbg(&port->dev, "%s offset is %x, return val %x\n", __func__, reg, *val);
286 
287 	kfree(buf);
288 	return ret;
289 }
290 
291 /*
292  * mos7840_set_uart_reg
293  *	To set the Uart register by calling usb_fill_control_urb function by
294  *	passing usb_sndctrlpipe function as parameter.
295  */
296 
297 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
298 				__u16 val)
299 {
300 
301 	struct usb_device *dev = port->serial->dev;
302 	val = val & 0x00ff;
303 	/* For the UART control registers, the application number need
304 	   to be Or'ed */
305 	if (port->serial->num_ports == 4) {
306 		val |= ((__u16)port->port_number + 1) << 8;
307 	} else {
308 		if (port->port_number == 0) {
309 			val |= ((__u16)port->port_number + 1) << 8;
310 		} else {
311 			val |= ((__u16)port->port_number + 2) << 8;
312 		}
313 	}
314 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, val);
315 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
316 			       MCS_WR_RTYPE, val, reg, NULL, 0,
317 			       MOS_WDR_TIMEOUT);
318 
319 }
320 
321 /*
322  * mos7840_get_uart_reg
323  *	To set the Control register by calling usb_fill_control_urb function
324  *	by passing usb_rcvctrlpipe function as parameter.
325  */
326 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
327 				__u16 *val)
328 {
329 	struct usb_device *dev = port->serial->dev;
330 	int ret = 0;
331 	__u16 Wval;
332 	u8 *buf;
333 
334 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
335 	if (!buf)
336 		return -ENOMEM;
337 
338 	/* Wval  is same as application number */
339 	if (port->serial->num_ports == 4) {
340 		Wval = ((__u16)port->port_number + 1) << 8;
341 	} else {
342 		if (port->port_number == 0) {
343 			Wval = ((__u16)port->port_number + 1) << 8;
344 		} else {
345 			Wval = ((__u16)port->port_number + 2) << 8;
346 		}
347 	}
348 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, Wval);
349 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
350 			      MCS_RD_RTYPE, Wval, reg, buf, VENDOR_READ_LENGTH,
351 			      MOS_WDR_TIMEOUT);
352 	*val = buf[0];
353 
354 	kfree(buf);
355 	return ret;
356 }
357 
358 static void mos7840_dump_serial_port(struct usb_serial_port *port,
359 				     struct moschip_port *mos7840_port)
360 {
361 
362 	dev_dbg(&port->dev, "SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
363 	dev_dbg(&port->dev, "ControlRegOffset is %2x\n", mos7840_port->ControlRegOffset);
364 	dev_dbg(&port->dev, "DCRRegOffset is %2x\n", mos7840_port->DcrRegOffset);
365 
366 }
367 
368 /************************************************************************/
369 /************************************************************************/
370 /*             I N T E R F A C E   F U N C T I O N S			*/
371 /*             I N T E R F A C E   F U N C T I O N S			*/
372 /************************************************************************/
373 /************************************************************************/
374 
375 static inline void mos7840_set_port_private(struct usb_serial_port *port,
376 					    struct moschip_port *data)
377 {
378 	usb_set_serial_port_data(port, (void *)data);
379 }
380 
381 static inline struct moschip_port *mos7840_get_port_private(struct
382 							    usb_serial_port
383 							    *port)
384 {
385 	return (struct moschip_port *)usb_get_serial_port_data(port);
386 }
387 
388 static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
389 {
390 	struct moschip_port *mos7840_port;
391 	struct async_icount *icount;
392 	mos7840_port = port;
393 	if (new_msr &
394 	    (MOS_MSR_DELTA_CTS | MOS_MSR_DELTA_DSR | MOS_MSR_DELTA_RI |
395 	     MOS_MSR_DELTA_CD)) {
396 		icount = &mos7840_port->port->icount;
397 
398 		/* update input line counters */
399 		if (new_msr & MOS_MSR_DELTA_CTS)
400 			icount->cts++;
401 		if (new_msr & MOS_MSR_DELTA_DSR)
402 			icount->dsr++;
403 		if (new_msr & MOS_MSR_DELTA_CD)
404 			icount->dcd++;
405 		if (new_msr & MOS_MSR_DELTA_RI)
406 			icount->rng++;
407 
408 		wake_up_interruptible(&port->port->port.delta_msr_wait);
409 	}
410 }
411 
412 static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)
413 {
414 	struct async_icount *icount;
415 
416 	if (new_lsr & SERIAL_LSR_BI) {
417 		/*
418 		 * Parity and Framing errors only count if they
419 		 * occur exclusive of a break being
420 		 * received.
421 		 */
422 		new_lsr &= (__u8) (SERIAL_LSR_OE | SERIAL_LSR_BI);
423 	}
424 
425 	/* update input line counters */
426 	icount = &port->port->icount;
427 	if (new_lsr & SERIAL_LSR_BI)
428 		icount->brk++;
429 	if (new_lsr & SERIAL_LSR_OE)
430 		icount->overrun++;
431 	if (new_lsr & SERIAL_LSR_PE)
432 		icount->parity++;
433 	if (new_lsr & SERIAL_LSR_FE)
434 		icount->frame++;
435 }
436 
437 /************************************************************************/
438 /************************************************************************/
439 /*            U S B  C A L L B A C K   F U N C T I O N S                */
440 /*            U S B  C A L L B A C K   F U N C T I O N S                */
441 /************************************************************************/
442 /************************************************************************/
443 
444 static void mos7840_control_callback(struct urb *urb)
445 {
446 	unsigned char *data;
447 	struct moschip_port *mos7840_port;
448 	struct device *dev = &urb->dev->dev;
449 	__u8 regval = 0x0;
450 	int status = urb->status;
451 
452 	mos7840_port = urb->context;
453 
454 	switch (status) {
455 	case 0:
456 		/* success */
457 		break;
458 	case -ECONNRESET:
459 	case -ENOENT:
460 	case -ESHUTDOWN:
461 		/* this urb is terminated, clean up */
462 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
463 		return;
464 	default:
465 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
466 		return;
467 	}
468 
469 	dev_dbg(dev, "%s urb buffer size is %d\n", __func__, urb->actual_length);
470 	dev_dbg(dev, "%s mos7840_port->MsrLsr is %d port %d\n", __func__,
471 		mos7840_port->MsrLsr, mos7840_port->port_num);
472 	data = urb->transfer_buffer;
473 	regval = (__u8) data[0];
474 	dev_dbg(dev, "%s data is %x\n", __func__, regval);
475 	if (mos7840_port->MsrLsr == 0)
476 		mos7840_handle_new_msr(mos7840_port, regval);
477 	else if (mos7840_port->MsrLsr == 1)
478 		mos7840_handle_new_lsr(mos7840_port, regval);
479 }
480 
481 static int mos7840_get_reg(struct moschip_port *mcs, __u16 Wval, __u16 reg,
482 			   __u16 *val)
483 {
484 	struct usb_device *dev = mcs->port->serial->dev;
485 	struct usb_ctrlrequest *dr = mcs->dr;
486 	unsigned char *buffer = mcs->ctrl_buf;
487 	int ret;
488 
489 	dr->bRequestType = MCS_RD_RTYPE;
490 	dr->bRequest = MCS_RDREQ;
491 	dr->wValue = cpu_to_le16(Wval);	/* 0 */
492 	dr->wIndex = cpu_to_le16(reg);
493 	dr->wLength = cpu_to_le16(2);
494 
495 	usb_fill_control_urb(mcs->control_urb, dev, usb_rcvctrlpipe(dev, 0),
496 			     (unsigned char *)dr, buffer, 2,
497 			     mos7840_control_callback, mcs);
498 	mcs->control_urb->transfer_buffer_length = 2;
499 	ret = usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
500 	return ret;
501 }
502 
503 static void mos7840_set_led_callback(struct urb *urb)
504 {
505 	switch (urb->status) {
506 	case 0:
507 		/* Success */
508 		break;
509 	case -ECONNRESET:
510 	case -ENOENT:
511 	case -ESHUTDOWN:
512 		/* This urb is terminated, clean up */
513 		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d",
514 			__func__, urb->status);
515 		break;
516 	default:
517 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d",
518 			__func__, urb->status);
519 	}
520 }
521 
522 static void mos7840_set_led_async(struct moschip_port *mcs, __u16 wval,
523 				__u16 reg)
524 {
525 	struct usb_device *dev = mcs->port->serial->dev;
526 	struct usb_ctrlrequest *dr = mcs->dr;
527 
528 	dr->bRequestType = MCS_WR_RTYPE;
529 	dr->bRequest = MCS_WRREQ;
530 	dr->wValue = cpu_to_le16(wval);
531 	dr->wIndex = cpu_to_le16(reg);
532 	dr->wLength = cpu_to_le16(0);
533 
534 	usb_fill_control_urb(mcs->control_urb, dev, usb_sndctrlpipe(dev, 0),
535 		(unsigned char *)dr, NULL, 0, mos7840_set_led_callback, NULL);
536 
537 	usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
538 }
539 
540 static void mos7840_set_led_sync(struct usb_serial_port *port, __u16 reg,
541 				__u16 val)
542 {
543 	struct usb_device *dev = port->serial->dev;
544 
545 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ, MCS_WR_RTYPE,
546 			val, reg, NULL, 0, MOS_WDR_TIMEOUT);
547 }
548 
549 static void mos7840_led_off(unsigned long arg)
550 {
551 	struct moschip_port *mcs = (struct moschip_port *) arg;
552 
553 	/* Turn off LED */
554 	mos7840_set_led_async(mcs, 0x0300, MODEM_CONTROL_REGISTER);
555 	mod_timer(&mcs->led_timer2,
556 				jiffies + msecs_to_jiffies(LED_OFF_MS));
557 }
558 
559 static void mos7840_led_flag_off(unsigned long arg)
560 {
561 	struct moschip_port *mcs = (struct moschip_port *) arg;
562 
563 	mcs->led_flag = false;
564 }
565 
566 /*****************************************************************************
567  * mos7840_interrupt_callback
568  *	this is the callback function for when we have received data on the
569  *	interrupt endpoint.
570  *****************************************************************************/
571 
572 static void mos7840_interrupt_callback(struct urb *urb)
573 {
574 	int result;
575 	int length;
576 	struct moschip_port *mos7840_port;
577 	struct usb_serial *serial;
578 	__u16 Data;
579 	unsigned char *data;
580 	__u8 sp[5], st;
581 	int i, rv = 0;
582 	__u16 wval, wreg = 0;
583 	int status = urb->status;
584 
585 	switch (status) {
586 	case 0:
587 		/* success */
588 		break;
589 	case -ECONNRESET:
590 	case -ENOENT:
591 	case -ESHUTDOWN:
592 		/* this urb is terminated, clean up */
593 		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
594 			__func__, status);
595 		return;
596 	default:
597 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
598 			__func__, status);
599 		goto exit;
600 	}
601 
602 	length = urb->actual_length;
603 	data = urb->transfer_buffer;
604 
605 	serial = urb->context;
606 
607 	/* Moschip get 5 bytes
608 	 * Byte 1 IIR Port 1 (port.number is 0)
609 	 * Byte 2 IIR Port 2 (port.number is 1)
610 	 * Byte 3 IIR Port 3 (port.number is 2)
611 	 * Byte 4 IIR Port 4 (port.number is 3)
612 	 * Byte 5 FIFO status for both */
613 
614 	if (length && length > 5) {
615 		dev_dbg(&urb->dev->dev, "%s", "Wrong data !!!\n");
616 		return;
617 	}
618 
619 	sp[0] = (__u8) data[0];
620 	sp[1] = (__u8) data[1];
621 	sp[2] = (__u8) data[2];
622 	sp[3] = (__u8) data[3];
623 	st = (__u8) data[4];
624 
625 	for (i = 0; i < serial->num_ports; i++) {
626 		mos7840_port = mos7840_get_port_private(serial->port[i]);
627 		wval = ((__u16)serial->port[i]->port_number + 1) << 8;
628 		if (mos7840_port->open) {
629 			if (sp[i] & 0x01) {
630 				dev_dbg(&urb->dev->dev, "SP%d No Interrupt !!!\n", i);
631 			} else {
632 				switch (sp[i] & 0x0f) {
633 				case SERIAL_IIR_RLS:
634 					dev_dbg(&urb->dev->dev, "Serial Port %d: Receiver status error or \n", i);
635 					dev_dbg(&urb->dev->dev, "address bit detected in 9-bit mode\n");
636 					mos7840_port->MsrLsr = 1;
637 					wreg = LINE_STATUS_REGISTER;
638 					break;
639 				case SERIAL_IIR_MS:
640 					dev_dbg(&urb->dev->dev, "Serial Port %d: Modem status change\n", i);
641 					mos7840_port->MsrLsr = 0;
642 					wreg = MODEM_STATUS_REGISTER;
643 					break;
644 				}
645 				rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
646 			}
647 		}
648 	}
649 	if (!(rv < 0))
650 		/* the completion handler for the control urb will resubmit */
651 		return;
652 exit:
653 	result = usb_submit_urb(urb, GFP_ATOMIC);
654 	if (result) {
655 		dev_err(&urb->dev->dev,
656 			"%s - Error %d submitting interrupt urb\n",
657 			__func__, result);
658 	}
659 }
660 
661 static int mos7840_port_paranoia_check(struct usb_serial_port *port,
662 				       const char *function)
663 {
664 	if (!port) {
665 		pr_debug("%s - port == NULL\n", function);
666 		return -1;
667 	}
668 	if (!port->serial) {
669 		pr_debug("%s - port->serial == NULL\n", function);
670 		return -1;
671 	}
672 
673 	return 0;
674 }
675 
676 /* Inline functions to check the sanity of a pointer that is passed to us */
677 static int mos7840_serial_paranoia_check(struct usb_serial *serial,
678 					 const char *function)
679 {
680 	if (!serial) {
681 		pr_debug("%s - serial == NULL\n", function);
682 		return -1;
683 	}
684 	if (!serial->type) {
685 		pr_debug("%s - serial->type == NULL!\n", function);
686 		return -1;
687 	}
688 
689 	return 0;
690 }
691 
692 static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
693 						 const char *function)
694 {
695 	/* if no port was specified, or it fails a paranoia check */
696 	if (!port ||
697 	    mos7840_port_paranoia_check(port, function) ||
698 	    mos7840_serial_paranoia_check(port->serial, function)) {
699 		/* then say that we don't have a valid usb_serial thing,
700 		 * which will end up genrating -ENODEV return values */
701 		return NULL;
702 	}
703 
704 	return port->serial;
705 }
706 
707 /*****************************************************************************
708  * mos7840_bulk_in_callback
709  *	this is the callback function for when we have received data on the
710  *	bulk in endpoint.
711  *****************************************************************************/
712 
713 static void mos7840_bulk_in_callback(struct urb *urb)
714 {
715 	int retval;
716 	unsigned char *data;
717 	struct usb_serial *serial;
718 	struct usb_serial_port *port;
719 	struct moschip_port *mos7840_port;
720 	int status = urb->status;
721 
722 	mos7840_port = urb->context;
723 	if (!mos7840_port)
724 		return;
725 
726 	if (status) {
727 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
728 		mos7840_port->read_urb_busy = false;
729 		return;
730 	}
731 
732 	port = mos7840_port->port;
733 	if (mos7840_port_paranoia_check(port, __func__)) {
734 		mos7840_port->read_urb_busy = false;
735 		return;
736 	}
737 
738 	serial = mos7840_get_usb_serial(port, __func__);
739 	if (!serial) {
740 		mos7840_port->read_urb_busy = false;
741 		return;
742 	}
743 
744 	data = urb->transfer_buffer;
745 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
746 
747 	if (urb->actual_length) {
748 		struct tty_port *tport = &mos7840_port->port->port;
749 		tty_insert_flip_string(tport, data, urb->actual_length);
750 		tty_flip_buffer_push(tport);
751 		port->icount.rx += urb->actual_length;
752 		dev_dbg(&port->dev, "icount.rx is %d:\n", port->icount.rx);
753 	}
754 
755 	if (!mos7840_port->read_urb) {
756 		dev_dbg(&port->dev, "%s", "URB KILLED !!!\n");
757 		mos7840_port->read_urb_busy = false;
758 		return;
759 	}
760 
761 	/* Turn on LED */
762 	if (mos7840_port->has_led && !mos7840_port->led_flag) {
763 		mos7840_port->led_flag = true;
764 		mos7840_set_led_async(mos7840_port, 0x0301,
765 					MODEM_CONTROL_REGISTER);
766 		mod_timer(&mos7840_port->led_timer1,
767 				jiffies + msecs_to_jiffies(LED_ON_MS));
768 	}
769 
770 	mos7840_port->read_urb_busy = true;
771 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
772 
773 	if (retval) {
774 		dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
775 		mos7840_port->read_urb_busy = false;
776 	}
777 }
778 
779 /*****************************************************************************
780  * mos7840_bulk_out_data_callback
781  *	this is the callback function for when we have finished sending
782  *	serial data on the bulk out endpoint.
783  *****************************************************************************/
784 
785 static void mos7840_bulk_out_data_callback(struct urb *urb)
786 {
787 	struct moschip_port *mos7840_port;
788 	struct usb_serial_port *port;
789 	int status = urb->status;
790 	int i;
791 
792 	mos7840_port = urb->context;
793 	port = mos7840_port->port;
794 	spin_lock(&mos7840_port->pool_lock);
795 	for (i = 0; i < NUM_URBS; i++) {
796 		if (urb == mos7840_port->write_urb_pool[i]) {
797 			mos7840_port->busy[i] = 0;
798 			break;
799 		}
800 	}
801 	spin_unlock(&mos7840_port->pool_lock);
802 
803 	if (status) {
804 		dev_dbg(&port->dev, "nonzero write bulk status received:%d\n", status);
805 		return;
806 	}
807 
808 	if (mos7840_port_paranoia_check(port, __func__))
809 		return;
810 
811 	if (mos7840_port->open)
812 		tty_port_tty_wakeup(&port->port);
813 
814 }
815 
816 /************************************************************************/
817 /*       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       */
818 /************************************************************************/
819 #ifdef MCSSerialProbe
820 static int mos7840_serial_probe(struct usb_serial *serial,
821 				const struct usb_device_id *id)
822 {
823 
824 	/*need to implement the mode_reg reading and updating\
825 	   structures usb_serial_ device_type\
826 	   (i.e num_ports, num_bulkin,bulkout etc) */
827 	/* Also we can update the changes  attach */
828 	return 1;
829 }
830 #endif
831 
832 /*****************************************************************************
833  * mos7840_open
834  *	this function is called by the tty driver when a port is opened
835  *	If successful, we return 0
836  *	Otherwise we return a negative error number.
837  *****************************************************************************/
838 
839 static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
840 {
841 	int response;
842 	int j;
843 	struct usb_serial *serial;
844 	struct urb *urb;
845 	__u16 Data;
846 	int status;
847 	struct moschip_port *mos7840_port;
848 	struct moschip_port *port0;
849 
850 	if (mos7840_port_paranoia_check(port, __func__))
851 		return -ENODEV;
852 
853 	serial = port->serial;
854 
855 	if (mos7840_serial_paranoia_check(serial, __func__))
856 		return -ENODEV;
857 
858 	mos7840_port = mos7840_get_port_private(port);
859 	port0 = mos7840_get_port_private(serial->port[0]);
860 
861 	if (mos7840_port == NULL || port0 == NULL)
862 		return -ENODEV;
863 
864 	usb_clear_halt(serial->dev, port->write_urb->pipe);
865 	usb_clear_halt(serial->dev, port->read_urb->pipe);
866 	port0->open_ports++;
867 
868 	/* Initialising the write urb pool */
869 	for (j = 0; j < NUM_URBS; ++j) {
870 		urb = usb_alloc_urb(0, GFP_KERNEL);
871 		mos7840_port->write_urb_pool[j] = urb;
872 
873 		if (urb == NULL) {
874 			dev_err(&port->dev, "No more urbs???\n");
875 			continue;
876 		}
877 
878 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
879 								GFP_KERNEL);
880 		if (!urb->transfer_buffer) {
881 			usb_free_urb(urb);
882 			mos7840_port->write_urb_pool[j] = NULL;
883 			dev_err(&port->dev,
884 				"%s-out of memory for urb buffers.\n",
885 				__func__);
886 			continue;
887 		}
888 	}
889 
890 /*****************************************************************************
891  * Initialize MCS7840 -- Write Init values to corresponding Registers
892  *
893  * Register Index
894  * 1 : IER
895  * 2 : FCR
896  * 3 : LCR
897  * 4 : MCR
898  *
899  * 0x08 : SP1/2 Control Reg
900  *****************************************************************************/
901 
902 	/* NEED to check the following Block */
903 
904 	Data = 0x0;
905 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
906 	if (status < 0) {
907 		dev_dbg(&port->dev, "Reading Spreg failed\n");
908 		return -1;
909 	}
910 	Data |= 0x80;
911 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
912 	if (status < 0) {
913 		dev_dbg(&port->dev, "writing Spreg failed\n");
914 		return -1;
915 	}
916 
917 	Data &= ~0x80;
918 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
919 	if (status < 0) {
920 		dev_dbg(&port->dev, "writing Spreg failed\n");
921 		return -1;
922 	}
923 	/* End of block to be checked */
924 
925 	Data = 0x0;
926 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
927 									&Data);
928 	if (status < 0) {
929 		dev_dbg(&port->dev, "Reading Controlreg failed\n");
930 		return -1;
931 	}
932 	Data |= 0x08;		/* Driver done bit */
933 	Data |= 0x20;		/* rx_disable */
934 	status = mos7840_set_reg_sync(port,
935 				mos7840_port->ControlRegOffset, Data);
936 	if (status < 0) {
937 		dev_dbg(&port->dev, "writing Controlreg failed\n");
938 		return -1;
939 	}
940 	/* do register settings here */
941 	/* Set all regs to the device default values. */
942 	/***********************************
943 	 * First Disable all interrupts.
944 	 ***********************************/
945 	Data = 0x00;
946 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
947 	if (status < 0) {
948 		dev_dbg(&port->dev, "disabling interrupts failed\n");
949 		return -1;
950 	}
951 	/* Set FIFO_CONTROL_REGISTER to the default value */
952 	Data = 0x00;
953 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
954 	if (status < 0) {
955 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
956 		return -1;
957 	}
958 
959 	Data = 0xcf;
960 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
961 	if (status < 0) {
962 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
963 		return -1;
964 	}
965 
966 	Data = 0x03;
967 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
968 	mos7840_port->shadowLCR = Data;
969 
970 	Data = 0x0b;
971 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
972 	mos7840_port->shadowMCR = Data;
973 
974 	Data = 0x00;
975 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
976 	mos7840_port->shadowLCR = Data;
977 
978 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
979 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
980 
981 	Data = 0x0c;
982 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
983 
984 	Data = 0x0;
985 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
986 
987 	Data = 0x00;
988 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
989 
990 	Data = Data & ~SERIAL_LCR_DLAB;
991 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
992 	mos7840_port->shadowLCR = Data;
993 
994 	/* clearing Bulkin and Bulkout Fifo */
995 	Data = 0x0;
996 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
997 
998 	Data = Data | 0x0c;
999 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
1000 
1001 	Data = Data & ~0x0c;
1002 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
1003 	/* Finally enable all interrupts */
1004 	Data = 0x0c;
1005 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1006 
1007 	/* clearing rx_disable */
1008 	Data = 0x0;
1009 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
1010 									&Data);
1011 	Data = Data & ~0x20;
1012 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
1013 									Data);
1014 
1015 	/* rx_negate */
1016 	Data = 0x0;
1017 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
1018 									&Data);
1019 	Data = Data | 0x10;
1020 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
1021 									Data);
1022 
1023 	/* Check to see if we've set up our endpoint info yet    *
1024 	 * (can't set it up in mos7840_startup as the structures *
1025 	 * were not set up at that time.)                        */
1026 	if (port0->open_ports == 1) {
1027 		if (serial->port[0]->interrupt_in_buffer == NULL) {
1028 			/* set up interrupt urb */
1029 			usb_fill_int_urb(serial->port[0]->interrupt_in_urb,
1030 				serial->dev,
1031 				usb_rcvintpipe(serial->dev,
1032 				serial->port[0]->interrupt_in_endpointAddress),
1033 				serial->port[0]->interrupt_in_buffer,
1034 				serial->port[0]->interrupt_in_urb->
1035 				transfer_buffer_length,
1036 				mos7840_interrupt_callback,
1037 				serial,
1038 				serial->port[0]->interrupt_in_urb->interval);
1039 
1040 			/* start interrupt read for mos7840               *
1041 			 * will continue as long as mos7840 is connected  */
1042 
1043 			response =
1044 			    usb_submit_urb(serial->port[0]->interrupt_in_urb,
1045 					   GFP_KERNEL);
1046 			if (response) {
1047 				dev_err(&port->dev, "%s - Error %d submitting "
1048 					"interrupt urb\n", __func__, response);
1049 			}
1050 
1051 		}
1052 
1053 	}
1054 
1055 	/* see if we've set up our endpoint info yet   *
1056 	 * (can't set it up in mos7840_startup as the  *
1057 	 * structures were not set up at that time.)   */
1058 
1059 	dev_dbg(&port->dev, "port number is %d\n", port->port_number);
1060 	dev_dbg(&port->dev, "minor number is %d\n", port->minor);
1061 	dev_dbg(&port->dev, "Bulkin endpoint is %d\n", port->bulk_in_endpointAddress);
1062 	dev_dbg(&port->dev, "BulkOut endpoint is %d\n", port->bulk_out_endpointAddress);
1063 	dev_dbg(&port->dev, "Interrupt endpoint is %d\n", port->interrupt_in_endpointAddress);
1064 	dev_dbg(&port->dev, "port's number in the device is %d\n", mos7840_port->port_num);
1065 	mos7840_port->read_urb = port->read_urb;
1066 
1067 	/* set up our bulk in urb */
1068 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
1069 		usb_fill_bulk_urb(mos7840_port->read_urb,
1070 			serial->dev,
1071 			usb_rcvbulkpipe(serial->dev,
1072 				(port->bulk_in_endpointAddress) + 2),
1073 			port->bulk_in_buffer,
1074 			mos7840_port->read_urb->transfer_buffer_length,
1075 			mos7840_bulk_in_callback, mos7840_port);
1076 	} else {
1077 		usb_fill_bulk_urb(mos7840_port->read_urb,
1078 			serial->dev,
1079 			usb_rcvbulkpipe(serial->dev,
1080 				port->bulk_in_endpointAddress),
1081 			port->bulk_in_buffer,
1082 			mos7840_port->read_urb->transfer_buffer_length,
1083 			mos7840_bulk_in_callback, mos7840_port);
1084 	}
1085 
1086 	dev_dbg(&port->dev, "%s: bulkin endpoint is %d\n", __func__, port->bulk_in_endpointAddress);
1087 	mos7840_port->read_urb_busy = true;
1088 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1089 	if (response) {
1090 		dev_err(&port->dev, "%s - Error %d submitting control urb\n",
1091 			__func__, response);
1092 		mos7840_port->read_urb_busy = false;
1093 	}
1094 
1095 	/* initialize our wait queues */
1096 	init_waitqueue_head(&mos7840_port->wait_chase);
1097 
1098 	/* initialize our port settings */
1099 	/* Must set to enable ints! */
1100 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1101 	/* send a open port command */
1102 	mos7840_port->open = 1;
1103 	/* mos7840_change_port_settings(mos7840_port,old_termios); */
1104 
1105 	return 0;
1106 }
1107 
1108 /*****************************************************************************
1109  * mos7840_chars_in_buffer
1110  *	this function is called by the tty driver when it wants to know how many
1111  *	bytes of data we currently have outstanding in the port (data that has
1112  *	been written, but hasn't made it out the port yet)
1113  *	If successful, we return the number of bytes left to be written in the
1114  *	system,
1115  *	Otherwise we return zero.
1116  *****************************************************************************/
1117 
1118 static int mos7840_chars_in_buffer(struct tty_struct *tty)
1119 {
1120 	struct usb_serial_port *port = tty->driver_data;
1121 	int i;
1122 	int chars = 0;
1123 	unsigned long flags;
1124 	struct moschip_port *mos7840_port;
1125 
1126 	if (mos7840_port_paranoia_check(port, __func__))
1127 		return 0;
1128 
1129 	mos7840_port = mos7840_get_port_private(port);
1130 	if (mos7840_port == NULL)
1131 		return 0;
1132 
1133 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1134 	for (i = 0; i < NUM_URBS; ++i) {
1135 		if (mos7840_port->busy[i]) {
1136 			struct urb *urb = mos7840_port->write_urb_pool[i];
1137 			chars += urb->transfer_buffer_length;
1138 		}
1139 	}
1140 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1141 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1142 	return chars;
1143 
1144 }
1145 
1146 /*****************************************************************************
1147  * mos7840_close
1148  *	this function is called by the tty driver when a port is closed
1149  *****************************************************************************/
1150 
1151 static void mos7840_close(struct usb_serial_port *port)
1152 {
1153 	struct usb_serial *serial;
1154 	struct moschip_port *mos7840_port;
1155 	struct moschip_port *port0;
1156 	int j;
1157 	__u16 Data;
1158 
1159 	if (mos7840_port_paranoia_check(port, __func__))
1160 		return;
1161 
1162 	serial = mos7840_get_usb_serial(port, __func__);
1163 	if (!serial)
1164 		return;
1165 
1166 	mos7840_port = mos7840_get_port_private(port);
1167 	port0 = mos7840_get_port_private(serial->port[0]);
1168 
1169 	if (mos7840_port == NULL || port0 == NULL)
1170 		return;
1171 
1172 	for (j = 0; j < NUM_URBS; ++j)
1173 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
1174 
1175 	/* Freeing Write URBs */
1176 	for (j = 0; j < NUM_URBS; ++j) {
1177 		if (mos7840_port->write_urb_pool[j]) {
1178 			if (mos7840_port->write_urb_pool[j]->transfer_buffer)
1179 				kfree(mos7840_port->write_urb_pool[j]->
1180 				      transfer_buffer);
1181 
1182 			usb_free_urb(mos7840_port->write_urb_pool[j]);
1183 		}
1184 	}
1185 
1186 	usb_kill_urb(mos7840_port->write_urb);
1187 	usb_kill_urb(mos7840_port->read_urb);
1188 	mos7840_port->read_urb_busy = false;
1189 
1190 	port0->open_ports--;
1191 	dev_dbg(&port->dev, "%s in close%d\n", __func__, port0->open_ports);
1192 	if (port0->open_ports == 0) {
1193 		if (serial->port[0]->interrupt_in_urb) {
1194 			dev_dbg(&port->dev, "Shutdown interrupt_in_urb\n");
1195 			usb_kill_urb(serial->port[0]->interrupt_in_urb);
1196 		}
1197 	}
1198 
1199 	if (mos7840_port->write_urb) {
1200 		/* if this urb had a transfer buffer already (old tx) free it */
1201 		kfree(mos7840_port->write_urb->transfer_buffer);
1202 		usb_free_urb(mos7840_port->write_urb);
1203 	}
1204 
1205 	Data = 0x0;
1206 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1207 
1208 	Data = 0x00;
1209 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1210 
1211 	mos7840_port->open = 0;
1212 }
1213 
1214 /************************************************************************
1215  *
1216  * mos7840_block_until_chase_response
1217  *
1218  *	This function will block the close until one of the following:
1219  *		1. Response to our Chase comes from mos7840
1220  *		2. A timeout of 10 seconds without activity has expired
1221  *		   (1K of mos7840 data @ 2400 baud ==> 4 sec to empty)
1222  *
1223  ************************************************************************/
1224 
1225 static void mos7840_block_until_chase_response(struct tty_struct *tty,
1226 					struct moschip_port *mos7840_port)
1227 {
1228 	int timeout = msecs_to_jiffies(1000);
1229 	int wait = 10;
1230 	int count;
1231 
1232 	while (1) {
1233 		count = mos7840_chars_in_buffer(tty);
1234 
1235 		/* Check for Buffer status */
1236 		if (count <= 0)
1237 			return;
1238 
1239 		/* Block the thread for a while */
1240 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1241 					       timeout);
1242 		/* No activity.. count down section */
1243 		wait--;
1244 		if (wait == 0) {
1245 			dev_dbg(&mos7840_port->port->dev, "%s - TIMEOUT\n", __func__);
1246 			return;
1247 		} else {
1248 			/* Reset timeout value back to seconds */
1249 			wait = 10;
1250 		}
1251 	}
1252 
1253 }
1254 
1255 /*****************************************************************************
1256  * mos7840_break
1257  *	this function sends a break to the port
1258  *****************************************************************************/
1259 static void mos7840_break(struct tty_struct *tty, int break_state)
1260 {
1261 	struct usb_serial_port *port = tty->driver_data;
1262 	unsigned char data;
1263 	struct usb_serial *serial;
1264 	struct moschip_port *mos7840_port;
1265 
1266 	if (mos7840_port_paranoia_check(port, __func__))
1267 		return;
1268 
1269 	serial = mos7840_get_usb_serial(port, __func__);
1270 	if (!serial)
1271 		return;
1272 
1273 	mos7840_port = mos7840_get_port_private(port);
1274 
1275 	if (mos7840_port == NULL)
1276 		return;
1277 
1278 	/* flush and block until tx is empty */
1279 	mos7840_block_until_chase_response(tty, mos7840_port);
1280 
1281 	if (break_state == -1)
1282 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
1283 	else
1284 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
1285 
1286 	/* FIXME: no locking on shadowLCR anywhere in driver */
1287 	mos7840_port->shadowLCR = data;
1288 	dev_dbg(&port->dev, "%s mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1289 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
1290 			     mos7840_port->shadowLCR);
1291 }
1292 
1293 /*****************************************************************************
1294  * mos7840_write_room
1295  *	this function is called by the tty driver when it wants to know how many
1296  *	bytes of data we can accept for a specific port.
1297  *	If successful, we return the amount of room that we have for this port
1298  *	Otherwise we return a negative error number.
1299  *****************************************************************************/
1300 
1301 static int mos7840_write_room(struct tty_struct *tty)
1302 {
1303 	struct usb_serial_port *port = tty->driver_data;
1304 	int i;
1305 	int room = 0;
1306 	unsigned long flags;
1307 	struct moschip_port *mos7840_port;
1308 
1309 	if (mos7840_port_paranoia_check(port, __func__))
1310 		return -1;
1311 
1312 	mos7840_port = mos7840_get_port_private(port);
1313 	if (mos7840_port == NULL)
1314 		return -1;
1315 
1316 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1317 	for (i = 0; i < NUM_URBS; ++i) {
1318 		if (!mos7840_port->busy[i])
1319 			room += URB_TRANSFER_BUFFER_SIZE;
1320 	}
1321 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1322 
1323 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
1324 	dev_dbg(&mos7840_port->port->dev, "%s - returns %d\n", __func__, room);
1325 	return room;
1326 
1327 }
1328 
1329 /*****************************************************************************
1330  * mos7840_write
1331  *	this function is called by the tty driver when data should be written to
1332  *	the port.
1333  *	If successful, we return the number of bytes written, otherwise we
1334  *      return a negative error number.
1335  *****************************************************************************/
1336 
1337 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
1338 			 const unsigned char *data, int count)
1339 {
1340 	int status;
1341 	int i;
1342 	int bytes_sent = 0;
1343 	int transfer_size;
1344 	unsigned long flags;
1345 
1346 	struct moschip_port *mos7840_port;
1347 	struct usb_serial *serial;
1348 	struct urb *urb;
1349 	/* __u16 Data; */
1350 	const unsigned char *current_position = data;
1351 	unsigned char *data1;
1352 
1353 #ifdef NOTMOS7840
1354 	Data = 0x00;
1355 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1356 	mos7840_port->shadowLCR = Data;
1357 	dev_dbg(&port->dev, "%s: LINE_CONTROL_REGISTER is %x\n", __func__, Data);
1358 	dev_dbg(&port->dev, "%s: mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1359 
1360 	/* Data = 0x03; */
1361 	/* status = mos7840_set_uart_reg(port,LINE_CONTROL_REGISTER,Data); */
1362 	/* mos7840_port->shadowLCR=Data;//Need to add later */
1363 
1364 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
1365 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1366 
1367 	/* Data = 0x0c; */
1368 	/* status = mos7840_set_uart_reg(port,DIVISOR_LATCH_LSB,Data); */
1369 	Data = 0x00;
1370 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_LSB, &Data);
1371 	dev_dbg(&port->dev, "%s: DLL value is %x\n", __func__, Data);
1372 
1373 	Data = 0x0;
1374 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_MSB, &Data);
1375 	dev_dbg(&port->dev, "%s: DLM value is %x\n", __func__, Data);
1376 
1377 	Data = Data & ~SERIAL_LCR_DLAB;
1378 	dev_dbg(&port->dev, "%s: mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1379 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1380 #endif
1381 
1382 	if (mos7840_port_paranoia_check(port, __func__))
1383 		return -1;
1384 
1385 	serial = port->serial;
1386 	if (mos7840_serial_paranoia_check(serial, __func__))
1387 		return -1;
1388 
1389 	mos7840_port = mos7840_get_port_private(port);
1390 	if (mos7840_port == NULL)
1391 		return -1;
1392 
1393 	/* try to find a free urb in the list */
1394 	urb = NULL;
1395 
1396 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1397 	for (i = 0; i < NUM_URBS; ++i) {
1398 		if (!mos7840_port->busy[i]) {
1399 			mos7840_port->busy[i] = 1;
1400 			urb = mos7840_port->write_urb_pool[i];
1401 			dev_dbg(&port->dev, "URB:%d\n", i);
1402 			break;
1403 		}
1404 	}
1405 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1406 
1407 	if (urb == NULL) {
1408 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1409 		goto exit;
1410 	}
1411 
1412 	if (urb->transfer_buffer == NULL) {
1413 		urb->transfer_buffer =
1414 		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
1415 
1416 		if (urb->transfer_buffer == NULL) {
1417 			dev_err_console(port, "%s no more kernel memory...\n",
1418 				__func__);
1419 			goto exit;
1420 		}
1421 	}
1422 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1423 
1424 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1425 
1426 	/* fill urb with data and submit  */
1427 	if ((serial->num_ports == 2) && (((__u16)port->port_number % 2) != 0)) {
1428 		usb_fill_bulk_urb(urb,
1429 			serial->dev,
1430 			usb_sndbulkpipe(serial->dev,
1431 				(port->bulk_out_endpointAddress) + 2),
1432 			urb->transfer_buffer,
1433 			transfer_size,
1434 			mos7840_bulk_out_data_callback, mos7840_port);
1435 	} else {
1436 		usb_fill_bulk_urb(urb,
1437 			serial->dev,
1438 			usb_sndbulkpipe(serial->dev,
1439 				port->bulk_out_endpointAddress),
1440 			urb->transfer_buffer,
1441 			transfer_size,
1442 			mos7840_bulk_out_data_callback, mos7840_port);
1443 	}
1444 
1445 	data1 = urb->transfer_buffer;
1446 	dev_dbg(&port->dev, "bulkout endpoint is %d\n", port->bulk_out_endpointAddress);
1447 
1448 	/* Turn on LED */
1449 	if (mos7840_port->has_led && !mos7840_port->led_flag) {
1450 		mos7840_port->led_flag = true;
1451 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0301);
1452 		mod_timer(&mos7840_port->led_timer1,
1453 				jiffies + msecs_to_jiffies(LED_ON_MS));
1454 	}
1455 
1456 	/* send it down the pipe */
1457 	status = usb_submit_urb(urb, GFP_ATOMIC);
1458 
1459 	if (status) {
1460 		mos7840_port->busy[i] = 0;
1461 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1462 			"with status = %d\n", __func__, status);
1463 		bytes_sent = status;
1464 		goto exit;
1465 	}
1466 	bytes_sent = transfer_size;
1467 	port->icount.tx += transfer_size;
1468 	dev_dbg(&port->dev, "icount.tx is %d:\n", port->icount.tx);
1469 exit:
1470 	return bytes_sent;
1471 
1472 }
1473 
1474 /*****************************************************************************
1475  * mos7840_throttle
1476  *	this function is called by the tty driver when it wants to stop the data
1477  *	being read from the port.
1478  *****************************************************************************/
1479 
1480 static void mos7840_throttle(struct tty_struct *tty)
1481 {
1482 	struct usb_serial_port *port = tty->driver_data;
1483 	struct moschip_port *mos7840_port;
1484 	int status;
1485 
1486 	if (mos7840_port_paranoia_check(port, __func__))
1487 		return;
1488 
1489 	mos7840_port = mos7840_get_port_private(port);
1490 
1491 	if (mos7840_port == NULL)
1492 		return;
1493 
1494 	if (!mos7840_port->open) {
1495 		dev_dbg(&port->dev, "%s", "port not opened\n");
1496 		return;
1497 	}
1498 
1499 	/* if we are implementing XON/XOFF, send the stop character */
1500 	if (I_IXOFF(tty)) {
1501 		unsigned char stop_char = STOP_CHAR(tty);
1502 		status = mos7840_write(tty, port, &stop_char, 1);
1503 		if (status <= 0)
1504 			return;
1505 	}
1506 	/* if we are implementing RTS/CTS, toggle that line */
1507 	if (tty->termios.c_cflag & CRTSCTS) {
1508 		mos7840_port->shadowMCR &= ~MCR_RTS;
1509 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1510 					 mos7840_port->shadowMCR);
1511 		if (status < 0)
1512 			return;
1513 	}
1514 }
1515 
1516 /*****************************************************************************
1517  * mos7840_unthrottle
1518  *	this function is called by the tty driver when it wants to resume
1519  *	the data being read from the port (called after mos7840_throttle is
1520  *	called)
1521  *****************************************************************************/
1522 static void mos7840_unthrottle(struct tty_struct *tty)
1523 {
1524 	struct usb_serial_port *port = tty->driver_data;
1525 	int status;
1526 	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
1527 
1528 	if (mos7840_port_paranoia_check(port, __func__))
1529 		return;
1530 
1531 	if (mos7840_port == NULL)
1532 		return;
1533 
1534 	if (!mos7840_port->open) {
1535 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1536 		return;
1537 	}
1538 
1539 	/* if we are implementing XON/XOFF, send the start character */
1540 	if (I_IXOFF(tty)) {
1541 		unsigned char start_char = START_CHAR(tty);
1542 		status = mos7840_write(tty, port, &start_char, 1);
1543 		if (status <= 0)
1544 			return;
1545 	}
1546 
1547 	/* if we are implementing RTS/CTS, toggle that line */
1548 	if (tty->termios.c_cflag & CRTSCTS) {
1549 		mos7840_port->shadowMCR |= MCR_RTS;
1550 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1551 					 mos7840_port->shadowMCR);
1552 		if (status < 0)
1553 			return;
1554 	}
1555 }
1556 
1557 static int mos7840_tiocmget(struct tty_struct *tty)
1558 {
1559 	struct usb_serial_port *port = tty->driver_data;
1560 	struct moschip_port *mos7840_port;
1561 	unsigned int result;
1562 	__u16 msr;
1563 	__u16 mcr;
1564 	int status;
1565 	mos7840_port = mos7840_get_port_private(port);
1566 
1567 	if (mos7840_port == NULL)
1568 		return -ENODEV;
1569 
1570 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
1571 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1572 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1573 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1574 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1575 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1576 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1577 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1578 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1579 
1580 	dev_dbg(&port->dev, "%s - 0x%04X\n", __func__, result);
1581 
1582 	return result;
1583 }
1584 
1585 static int mos7840_tiocmset(struct tty_struct *tty,
1586 			    unsigned int set, unsigned int clear)
1587 {
1588 	struct usb_serial_port *port = tty->driver_data;
1589 	struct moschip_port *mos7840_port;
1590 	unsigned int mcr;
1591 	int status;
1592 
1593 	mos7840_port = mos7840_get_port_private(port);
1594 
1595 	if (mos7840_port == NULL)
1596 		return -ENODEV;
1597 
1598 	/* FIXME: What locks the port registers ? */
1599 	mcr = mos7840_port->shadowMCR;
1600 	if (clear & TIOCM_RTS)
1601 		mcr &= ~MCR_RTS;
1602 	if (clear & TIOCM_DTR)
1603 		mcr &= ~MCR_DTR;
1604 	if (clear & TIOCM_LOOP)
1605 		mcr &= ~MCR_LOOPBACK;
1606 
1607 	if (set & TIOCM_RTS)
1608 		mcr |= MCR_RTS;
1609 	if (set & TIOCM_DTR)
1610 		mcr |= MCR_DTR;
1611 	if (set & TIOCM_LOOP)
1612 		mcr |= MCR_LOOPBACK;
1613 
1614 	mos7840_port->shadowMCR = mcr;
1615 
1616 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1617 	if (status < 0) {
1618 		dev_dbg(&port->dev, "setting MODEM_CONTROL_REGISTER Failed\n");
1619 		return status;
1620 	}
1621 
1622 	return 0;
1623 }
1624 
1625 /*****************************************************************************
1626  * mos7840_calc_baud_rate_divisor
1627  *	this function calculates the proper baud rate divisor for the specified
1628  *	baud rate.
1629  *****************************************************************************/
1630 static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
1631 					  int baudRate, int *divisor,
1632 					  __u16 *clk_sel_val)
1633 {
1634 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudRate);
1635 
1636 	if (baudRate <= 115200) {
1637 		*divisor = 115200 / baudRate;
1638 		*clk_sel_val = 0x0;
1639 	}
1640 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1641 		*divisor = 230400 / baudRate;
1642 		*clk_sel_val = 0x10;
1643 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1644 		*divisor = 403200 / baudRate;
1645 		*clk_sel_val = 0x20;
1646 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1647 		*divisor = 460800 / baudRate;
1648 		*clk_sel_val = 0x30;
1649 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1650 		*divisor = 806400 / baudRate;
1651 		*clk_sel_val = 0x40;
1652 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1653 		*divisor = 921600 / baudRate;
1654 		*clk_sel_val = 0x50;
1655 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1656 		*divisor = 1572864 / baudRate;
1657 		*clk_sel_val = 0x60;
1658 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1659 		*divisor = 3145728 / baudRate;
1660 		*clk_sel_val = 0x70;
1661 	}
1662 	return 0;
1663 
1664 #ifdef NOTMCS7840
1665 
1666 	for (i = 0; i < ARRAY_SIZE(mos7840_divisor_table); i++) {
1667 		if (mos7840_divisor_table[i].BaudRate == baudrate) {
1668 			*divisor = mos7840_divisor_table[i].Divisor;
1669 			return 0;
1670 		}
1671 	}
1672 
1673 	/* After trying for all the standard baud rates    *
1674 	 * Try calculating the divisor for this baud rate  */
1675 
1676 	if (baudrate > 75 && baudrate < 230400) {
1677 		/* get the divisor */
1678 		custom = (__u16) (230400L / baudrate);
1679 
1680 		/* Check for round off */
1681 		round1 = (__u16) (2304000L / baudrate);
1682 		round = (__u16) (round1 - (custom * 10));
1683 		if (round > 4)
1684 			custom++;
1685 		*divisor = custom;
1686 
1687 		dev_dbg(&port->dev, " Baud %d = %d\n", baudrate, custom);
1688 		return 0;
1689 	}
1690 
1691 	dev_dbg(&port->dev, "%s", " Baud calculation Failed...\n");
1692 	return -1;
1693 #endif
1694 }
1695 
1696 /*****************************************************************************
1697  * mos7840_send_cmd_write_baud_rate
1698  *	this function sends the proper command to change the baud rate of the
1699  *	specified port.
1700  *****************************************************************************/
1701 
1702 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1703 					    int baudRate)
1704 {
1705 	int divisor = 0;
1706 	int status;
1707 	__u16 Data;
1708 	unsigned char number;
1709 	__u16 clk_sel_val;
1710 	struct usb_serial_port *port;
1711 
1712 	if (mos7840_port == NULL)
1713 		return -1;
1714 
1715 	port = mos7840_port->port;
1716 	if (mos7840_port_paranoia_check(port, __func__))
1717 		return -1;
1718 
1719 	if (mos7840_serial_paranoia_check(port->serial, __func__))
1720 		return -1;
1721 
1722 	number = mos7840_port->port->port_number;
1723 
1724 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudRate);
1725 	/* reset clk_uart_sel in spregOffset */
1726 	if (baudRate > 115200) {
1727 #ifdef HW_flow_control
1728 		/* NOTE: need to see the pther register to modify */
1729 		/* setting h/w flow control bit to 1 */
1730 		Data = 0x2b;
1731 		mos7840_port->shadowMCR = Data;
1732 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1733 									Data);
1734 		if (status < 0) {
1735 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1736 			return -1;
1737 		}
1738 #endif
1739 
1740 	} else {
1741 #ifdef HW_flow_control
1742 		/* setting h/w flow control bit to 0 */
1743 		Data = 0xb;
1744 		mos7840_port->shadowMCR = Data;
1745 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1746 									Data);
1747 		if (status < 0) {
1748 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1749 			return -1;
1750 		}
1751 #endif
1752 
1753 	}
1754 
1755 	if (1) {		/* baudRate <= 115200) */
1756 		clk_sel_val = 0x0;
1757 		Data = 0x0;
1758 		status = mos7840_calc_baud_rate_divisor(port, baudRate, &divisor,
1759 						   &clk_sel_val);
1760 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1761 								 &Data);
1762 		if (status < 0) {
1763 			dev_dbg(&port->dev, "reading spreg failed in set_serial_baud\n");
1764 			return -1;
1765 		}
1766 		Data = (Data & 0x8f) | clk_sel_val;
1767 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1768 								Data);
1769 		if (status < 0) {
1770 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1771 			return -1;
1772 		}
1773 		/* Calculate the Divisor */
1774 
1775 		if (status) {
1776 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1777 			return status;
1778 		}
1779 		/* Enable access to divisor latch */
1780 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1781 		mos7840_port->shadowLCR = Data;
1782 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1783 
1784 		/* Write the divisor */
1785 		Data = (unsigned char)(divisor & 0xff);
1786 		dev_dbg(&port->dev, "set_serial_baud Value to write DLL is %x\n", Data);
1787 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1788 
1789 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1790 		dev_dbg(&port->dev, "set_serial_baud Value to write DLM is %x\n", Data);
1791 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1792 
1793 		/* Disable access to divisor latch */
1794 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1795 		mos7840_port->shadowLCR = Data;
1796 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1797 
1798 	}
1799 	return status;
1800 }
1801 
1802 /*****************************************************************************
1803  * mos7840_change_port_settings
1804  *	This routine is called to set the UART on the device to match
1805  *      the specified new settings.
1806  *****************************************************************************/
1807 
1808 static void mos7840_change_port_settings(struct tty_struct *tty,
1809 	struct moschip_port *mos7840_port, struct ktermios *old_termios)
1810 {
1811 	int baud;
1812 	unsigned cflag;
1813 	unsigned iflag;
1814 	__u8 lData;
1815 	__u8 lParity;
1816 	__u8 lStop;
1817 	int status;
1818 	__u16 Data;
1819 	struct usb_serial_port *port;
1820 	struct usb_serial *serial;
1821 
1822 	if (mos7840_port == NULL)
1823 		return;
1824 
1825 	port = mos7840_port->port;
1826 
1827 	if (mos7840_port_paranoia_check(port, __func__))
1828 		return;
1829 
1830 	if (mos7840_serial_paranoia_check(port->serial, __func__))
1831 		return;
1832 
1833 	serial = port->serial;
1834 
1835 	if (!mos7840_port->open) {
1836 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1837 		return;
1838 	}
1839 
1840 	lData = LCR_BITS_8;
1841 	lStop = LCR_STOP_1;
1842 	lParity = LCR_PAR_NONE;
1843 
1844 	cflag = tty->termios.c_cflag;
1845 	iflag = tty->termios.c_iflag;
1846 
1847 	/* Change the number of bits */
1848 	if (cflag & CSIZE) {
1849 		switch (cflag & CSIZE) {
1850 		case CS5:
1851 			lData = LCR_BITS_5;
1852 			break;
1853 
1854 		case CS6:
1855 			lData = LCR_BITS_6;
1856 			break;
1857 
1858 		case CS7:
1859 			lData = LCR_BITS_7;
1860 			break;
1861 		default:
1862 		case CS8:
1863 			lData = LCR_BITS_8;
1864 			break;
1865 		}
1866 	}
1867 	/* Change the Parity bit */
1868 	if (cflag & PARENB) {
1869 		if (cflag & PARODD) {
1870 			lParity = LCR_PAR_ODD;
1871 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1872 		} else {
1873 			lParity = LCR_PAR_EVEN;
1874 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1875 		}
1876 
1877 	} else {
1878 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1879 	}
1880 
1881 	if (cflag & CMSPAR)
1882 		lParity = lParity | 0x20;
1883 
1884 	/* Change the Stop bit */
1885 	if (cflag & CSTOPB) {
1886 		lStop = LCR_STOP_2;
1887 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1888 	} else {
1889 		lStop = LCR_STOP_1;
1890 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1891 	}
1892 
1893 	/* Update the LCR with the correct value */
1894 	mos7840_port->shadowLCR &=
1895 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1896 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1897 
1898 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is %x\n", __func__,
1899 		mos7840_port->shadowLCR);
1900 	/* Disable Interrupts */
1901 	Data = 0x00;
1902 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1903 
1904 	Data = 0x00;
1905 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1906 
1907 	Data = 0xcf;
1908 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1909 
1910 	/* Send the updated LCR value to the mos7840 */
1911 	Data = mos7840_port->shadowLCR;
1912 
1913 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1914 
1915 	Data = 0x00b;
1916 	mos7840_port->shadowMCR = Data;
1917 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1918 	Data = 0x00b;
1919 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1920 
1921 	/* set up the MCR register and send it to the mos7840 */
1922 
1923 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1924 	if (cflag & CBAUD)
1925 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
1926 
1927 	if (cflag & CRTSCTS)
1928 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
1929 	else
1930 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
1931 
1932 	Data = mos7840_port->shadowMCR;
1933 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1934 
1935 	/* Determine divisor based on baud rate */
1936 	baud = tty_get_baud_rate(tty);
1937 
1938 	if (!baud) {
1939 		/* pick a default, any default... */
1940 		dev_dbg(&port->dev, "%s", "Picked default baud...\n");
1941 		baud = 9600;
1942 	}
1943 
1944 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1945 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
1946 
1947 	/* Enable Interrupts */
1948 	Data = 0x0c;
1949 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1950 
1951 	if (mos7840_port->read_urb_busy == false) {
1952 		mos7840_port->read_urb_busy = true;
1953 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
1954 		if (status) {
1955 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
1956 			    status);
1957 			mos7840_port->read_urb_busy = false;
1958 		}
1959 	}
1960 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
1961 		mos7840_port->shadowLCR);
1962 }
1963 
1964 /*****************************************************************************
1965  * mos7840_set_termios
1966  *	this function is called by the tty driver when it wants to change
1967  *	the termios structure
1968  *****************************************************************************/
1969 
1970 static void mos7840_set_termios(struct tty_struct *tty,
1971 				struct usb_serial_port *port,
1972 				struct ktermios *old_termios)
1973 {
1974 	int status;
1975 	unsigned int cflag;
1976 	struct usb_serial *serial;
1977 	struct moschip_port *mos7840_port;
1978 
1979 	if (mos7840_port_paranoia_check(port, __func__))
1980 		return;
1981 
1982 	serial = port->serial;
1983 
1984 	if (mos7840_serial_paranoia_check(serial, __func__))
1985 		return;
1986 
1987 	mos7840_port = mos7840_get_port_private(port);
1988 
1989 	if (mos7840_port == NULL)
1990 		return;
1991 
1992 	if (!mos7840_port->open) {
1993 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1994 		return;
1995 	}
1996 
1997 	dev_dbg(&port->dev, "%s", "setting termios - \n");
1998 
1999 	cflag = tty->termios.c_cflag;
2000 
2001 	dev_dbg(&port->dev, "%s - clfag %08x iflag %08x\n", __func__,
2002 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
2003 	dev_dbg(&port->dev, "%s - old clfag %08x old iflag %08x\n", __func__,
2004 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
2005 
2006 	/* change the port settings to the new ones specified */
2007 
2008 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
2009 
2010 	if (!mos7840_port->read_urb) {
2011 		dev_dbg(&port->dev, "%s", "URB KILLED !!!!!\n");
2012 		return;
2013 	}
2014 
2015 	if (mos7840_port->read_urb_busy == false) {
2016 		mos7840_port->read_urb_busy = true;
2017 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2018 		if (status) {
2019 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
2020 			    status);
2021 			mos7840_port->read_urb_busy = false;
2022 		}
2023 	}
2024 }
2025 
2026 /*****************************************************************************
2027  * mos7840_get_lsr_info - get line status register info
2028  *
2029  * Purpose: Let user call ioctl() to get info when the UART physically
2030  * 	    is emptied.  On bus types like RS485, the transmitter must
2031  * 	    release the bus after transmitting. This must be done when
2032  * 	    the transmit shift register is empty, not be done when the
2033  * 	    transmit holding register is empty.  This functionality
2034  * 	    allows an RS485 driver to be written in user space.
2035  *****************************************************************************/
2036 
2037 static int mos7840_get_lsr_info(struct tty_struct *tty,
2038 				unsigned int __user *value)
2039 {
2040 	int count;
2041 	unsigned int result = 0;
2042 
2043 	count = mos7840_chars_in_buffer(tty);
2044 	if (count == 0)
2045 		result = TIOCSER_TEMT;
2046 
2047 	if (copy_to_user(value, &result, sizeof(int)))
2048 		return -EFAULT;
2049 	return 0;
2050 }
2051 
2052 /*****************************************************************************
2053  * mos7840_get_serial_info
2054  *      function to get information about serial port
2055  *****************************************************************************/
2056 
2057 static int mos7840_get_serial_info(struct moschip_port *mos7840_port,
2058 				   struct serial_struct __user *retinfo)
2059 {
2060 	struct serial_struct tmp;
2061 
2062 	if (mos7840_port == NULL)
2063 		return -1;
2064 
2065 	if (!retinfo)
2066 		return -EFAULT;
2067 
2068 	memset(&tmp, 0, sizeof(tmp));
2069 
2070 	tmp.type = PORT_16550A;
2071 	tmp.line = mos7840_port->port->minor;
2072 	tmp.port = mos7840_port->port->port_number;
2073 	tmp.irq = 0;
2074 	tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
2075 	tmp.xmit_fifo_size = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
2076 	tmp.baud_base = 9600;
2077 	tmp.close_delay = 5 * HZ;
2078 	tmp.closing_wait = 30 * HZ;
2079 
2080 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
2081 		return -EFAULT;
2082 	return 0;
2083 }
2084 
2085 /*****************************************************************************
2086  * SerialIoctl
2087  *	this function handles any ioctl calls to the driver
2088  *****************************************************************************/
2089 
2090 static int mos7840_ioctl(struct tty_struct *tty,
2091 			 unsigned int cmd, unsigned long arg)
2092 {
2093 	struct usb_serial_port *port = tty->driver_data;
2094 	void __user *argp = (void __user *)arg;
2095 	struct moschip_port *mos7840_port;
2096 
2097 	if (mos7840_port_paranoia_check(port, __func__))
2098 		return -1;
2099 
2100 	mos7840_port = mos7840_get_port_private(port);
2101 
2102 	if (mos7840_port == NULL)
2103 		return -1;
2104 
2105 	dev_dbg(&port->dev, "%s - cmd = 0x%x\n", __func__, cmd);
2106 
2107 	switch (cmd) {
2108 		/* return number of bytes available */
2109 
2110 	case TIOCSERGETLSR:
2111 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
2112 		return mos7840_get_lsr_info(tty, argp);
2113 
2114 	case TIOCGSERIAL:
2115 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
2116 		return mos7840_get_serial_info(mos7840_port, argp);
2117 
2118 	case TIOCSSERIAL:
2119 		dev_dbg(&port->dev, "%s TIOCSSERIAL\n", __func__);
2120 		break;
2121 	default:
2122 		break;
2123 	}
2124 	return -ENOIOCTLCMD;
2125 }
2126 
2127 static int mos7810_check(struct usb_serial *serial)
2128 {
2129 	int i, pass_count = 0;
2130 	u8 *buf;
2131 	__u16 data = 0, mcr_data = 0;
2132 	__u16 test_pattern = 0x55AA;
2133 	int res;
2134 
2135 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
2136 	if (!buf)
2137 		return 0;	/* failed to identify 7810 */
2138 
2139 	/* Store MCR setting */
2140 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2141 		MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
2142 		buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2143 	if (res == VENDOR_READ_LENGTH)
2144 		mcr_data = *buf;
2145 
2146 	for (i = 0; i < 16; i++) {
2147 		/* Send the 1-bit test pattern out to MCS7810 test pin */
2148 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2149 			MCS_WRREQ, MCS_WR_RTYPE,
2150 			(0x0300 | (((test_pattern >> i) & 0x0001) << 1)),
2151 			MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
2152 
2153 		/* Read the test pattern back */
2154 		res = usb_control_msg(serial->dev,
2155 				usb_rcvctrlpipe(serial->dev, 0), MCS_RDREQ,
2156 				MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
2157 				VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2158 		if (res == VENDOR_READ_LENGTH)
2159 			data = *buf;
2160 
2161 		/* If this is a MCS7810 device, both test patterns must match */
2162 		if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
2163 			break;
2164 
2165 		pass_count++;
2166 	}
2167 
2168 	/* Restore MCR setting */
2169 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), MCS_WRREQ,
2170 		MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
2171 		0, MOS_WDR_TIMEOUT);
2172 
2173 	kfree(buf);
2174 
2175 	if (pass_count == 16)
2176 		return 1;
2177 
2178 	return 0;
2179 }
2180 
2181 static int mos7840_calc_num_ports(struct usb_serial *serial)
2182 {
2183 	__u16 data = 0x00;
2184 	u8 *buf;
2185 	int mos7840_num_ports;
2186 
2187 	buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
2188 	if (buf) {
2189 		usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2190 			MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, buf,
2191 			VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2192 		data = *buf;
2193 		kfree(buf);
2194 	}
2195 
2196 	if (serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7810 ||
2197 		serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7820) {
2198 		device_type = serial->dev->descriptor.idProduct;
2199 	} else {
2200 		/* For a MCS7840 device GPIO0 must be set to 1 */
2201 		if ((data & 0x01) == 1)
2202 			device_type = MOSCHIP_DEVICE_ID_7840;
2203 		else if (mos7810_check(serial))
2204 			device_type = MOSCHIP_DEVICE_ID_7810;
2205 		else
2206 			device_type = MOSCHIP_DEVICE_ID_7820;
2207 	}
2208 
2209 	mos7840_num_ports = (device_type >> 4) & 0x000F;
2210 	serial->num_bulk_in = mos7840_num_ports;
2211 	serial->num_bulk_out = mos7840_num_ports;
2212 	serial->num_ports = mos7840_num_ports;
2213 
2214 	return mos7840_num_ports;
2215 }
2216 
2217 static int mos7840_port_probe(struct usb_serial_port *port)
2218 {
2219 	struct usb_serial *serial = port->serial;
2220 	struct moschip_port *mos7840_port;
2221 	int status;
2222 	int pnum;
2223 	__u16 Data;
2224 
2225 	/* we set up the pointers to the endpoints in the mos7840_open *
2226 	 * function, as the structures aren't created yet.             */
2227 
2228 	pnum = port->port_number;
2229 
2230 	dev_dbg(&port->dev, "mos7840_startup: configuring port %d\n", pnum);
2231 	mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2232 	if (mos7840_port == NULL) {
2233 		dev_err(&port->dev, "%s - Out of memory\n", __func__);
2234 		return -ENOMEM;
2235 	}
2236 
2237 	/* Initialize all port interrupt end point to port 0 int
2238 	 * endpoint. Our device has only one interrupt end point
2239 	 * common to all port */
2240 
2241 	mos7840_port->port = port;
2242 	mos7840_set_port_private(port, mos7840_port);
2243 	spin_lock_init(&mos7840_port->pool_lock);
2244 
2245 	/* minor is not initialised until later by
2246 	 * usb-serial.c:get_free_serial() and cannot therefore be used
2247 	 * to index device instances */
2248 	mos7840_port->port_num = pnum + 1;
2249 	dev_dbg(&port->dev, "port->minor = %d\n", port->minor);
2250 	dev_dbg(&port->dev, "mos7840_port->port_num = %d\n", mos7840_port->port_num);
2251 
2252 	if (mos7840_port->port_num == 1) {
2253 		mos7840_port->SpRegOffset = 0x0;
2254 		mos7840_port->ControlRegOffset = 0x1;
2255 		mos7840_port->DcrRegOffset = 0x4;
2256 	} else if ((mos7840_port->port_num == 2) && (serial->num_ports == 4)) {
2257 		mos7840_port->SpRegOffset = 0x8;
2258 		mos7840_port->ControlRegOffset = 0x9;
2259 		mos7840_port->DcrRegOffset = 0x16;
2260 	} else if ((mos7840_port->port_num == 2) && (serial->num_ports == 2)) {
2261 		mos7840_port->SpRegOffset = 0xa;
2262 		mos7840_port->ControlRegOffset = 0xb;
2263 		mos7840_port->DcrRegOffset = 0x19;
2264 	} else if ((mos7840_port->port_num == 3) && (serial->num_ports == 4)) {
2265 		mos7840_port->SpRegOffset = 0xa;
2266 		mos7840_port->ControlRegOffset = 0xb;
2267 		mos7840_port->DcrRegOffset = 0x19;
2268 	} else if ((mos7840_port->port_num == 4) && (serial->num_ports == 4)) {
2269 		mos7840_port->SpRegOffset = 0xc;
2270 		mos7840_port->ControlRegOffset = 0xd;
2271 		mos7840_port->DcrRegOffset = 0x1c;
2272 	}
2273 	mos7840_dump_serial_port(port, mos7840_port);
2274 	mos7840_set_port_private(port, mos7840_port);
2275 
2276 	/* enable rx_disable bit in control register */
2277 	status = mos7840_get_reg_sync(port,
2278 			mos7840_port->ControlRegOffset, &Data);
2279 	if (status < 0) {
2280 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
2281 		goto out;
2282 	} else
2283 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
2284 	Data |= 0x08;	/* setting driver done bit */
2285 	Data |= 0x04;	/* sp1_bit to have cts change reflect in
2286 			   modem status reg */
2287 
2288 	/* Data |= 0x20; //rx_disable bit */
2289 	status = mos7840_set_reg_sync(port,
2290 			mos7840_port->ControlRegOffset, Data);
2291 	if (status < 0) {
2292 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
2293 		goto out;
2294 	} else
2295 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
2296 
2297 	/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
2298 	   and 0x24 in DCR3 */
2299 	Data = 0x01;
2300 	status = mos7840_set_reg_sync(port,
2301 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
2302 	if (status < 0) {
2303 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
2304 		goto out;
2305 	} else
2306 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
2307 
2308 	Data = 0x05;
2309 	status = mos7840_set_reg_sync(port,
2310 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
2311 	if (status < 0) {
2312 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
2313 		goto out;
2314 	} else
2315 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
2316 
2317 	Data = 0x24;
2318 	status = mos7840_set_reg_sync(port,
2319 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
2320 	if (status < 0) {
2321 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
2322 		goto out;
2323 	} else
2324 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
2325 
2326 	/* write values in clkstart0x0 and clkmulti 0x20 */
2327 	Data = 0x0;
2328 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
2329 	if (status < 0) {
2330 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
2331 		goto out;
2332 	} else
2333 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
2334 
2335 	Data = 0x20;
2336 	status = mos7840_set_reg_sync(port, CLK_MULTI_REGISTER, Data);
2337 	if (status < 0) {
2338 		dev_dbg(&port->dev, "Writing CLK_MULTI_REGISTER failed status-0x%x\n", status);
2339 		goto error;
2340 	} else
2341 		dev_dbg(&port->dev, "CLK_MULTI_REGISTER Writing success status%d\n", status);
2342 
2343 	/* write value 0x0 to scratchpad register */
2344 	Data = 0x00;
2345 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
2346 	if (status < 0) {
2347 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
2348 		goto out;
2349 	} else
2350 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
2351 
2352 	/* Zero Length flag register */
2353 	if ((mos7840_port->port_num != 1) && (serial->num_ports == 2)) {
2354 		Data = 0xff;
2355 		status = mos7840_set_reg_sync(port,
2356 				(__u16) (ZLP_REG1 +
2357 					((__u16)mos7840_port->port_num)), Data);
2358 		dev_dbg(&port->dev, "ZLIP offset %x\n",
2359 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
2360 		if (status < 0) {
2361 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
2362 			goto out;
2363 		} else
2364 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
2365 	} else {
2366 		Data = 0xff;
2367 		status = mos7840_set_reg_sync(port,
2368 				(__u16) (ZLP_REG1 +
2369 					((__u16)mos7840_port->port_num) - 0x1), Data);
2370 		dev_dbg(&port->dev, "ZLIP offset %x\n",
2371 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
2372 		if (status < 0) {
2373 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
2374 			goto out;
2375 		} else
2376 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
2377 
2378 	}
2379 	mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
2380 	mos7840_port->ctrl_buf = kmalloc(16, GFP_KERNEL);
2381 	mos7840_port->dr = kmalloc(sizeof(struct usb_ctrlrequest),
2382 			GFP_KERNEL);
2383 	if (!mos7840_port->control_urb || !mos7840_port->ctrl_buf ||
2384 			!mos7840_port->dr) {
2385 		status = -ENOMEM;
2386 		goto error;
2387 	}
2388 
2389 	mos7840_port->has_led = false;
2390 
2391 	/* Initialize LED timers */
2392 	if (device_type == MOSCHIP_DEVICE_ID_7810) {
2393 		mos7840_port->has_led = true;
2394 
2395 		init_timer(&mos7840_port->led_timer1);
2396 		mos7840_port->led_timer1.function = mos7840_led_off;
2397 		mos7840_port->led_timer1.expires =
2398 			jiffies + msecs_to_jiffies(LED_ON_MS);
2399 		mos7840_port->led_timer1.data = (unsigned long)mos7840_port;
2400 
2401 		init_timer(&mos7840_port->led_timer2);
2402 		mos7840_port->led_timer2.function = mos7840_led_flag_off;
2403 		mos7840_port->led_timer2.expires =
2404 			jiffies + msecs_to_jiffies(LED_OFF_MS);
2405 		mos7840_port->led_timer2.data = (unsigned long)mos7840_port;
2406 
2407 		mos7840_port->led_flag = false;
2408 
2409 		/* Turn off LED */
2410 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
2411 	}
2412 out:
2413 	if (pnum == serial->num_ports - 1) {
2414 		/* Zero Length flag enable */
2415 		Data = 0x0f;
2416 		status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
2417 		if (status < 0) {
2418 			dev_dbg(&port->dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
2419 			goto error;
2420 		} else
2421 			dev_dbg(&port->dev, "ZLP_REG5 Writing success status%d\n", status);
2422 
2423 		/* setting configuration feature to one */
2424 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2425 				0x03, 0x00, 0x01, 0x00, NULL, 0x00,
2426 				MOS_WDR_TIMEOUT);
2427 	}
2428 	return 0;
2429 error:
2430 	kfree(mos7840_port->dr);
2431 	kfree(mos7840_port->ctrl_buf);
2432 	usb_free_urb(mos7840_port->control_urb);
2433 	kfree(mos7840_port);
2434 
2435 	return status;
2436 }
2437 
2438 static int mos7840_port_remove(struct usb_serial_port *port)
2439 {
2440 	struct moschip_port *mos7840_port;
2441 
2442 	mos7840_port = mos7840_get_port_private(port);
2443 
2444 	if (mos7840_port->has_led) {
2445 		/* Turn off LED */
2446 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
2447 
2448 		del_timer_sync(&mos7840_port->led_timer1);
2449 		del_timer_sync(&mos7840_port->led_timer2);
2450 	}
2451 	usb_kill_urb(mos7840_port->control_urb);
2452 	usb_free_urb(mos7840_port->control_urb);
2453 	kfree(mos7840_port->ctrl_buf);
2454 	kfree(mos7840_port->dr);
2455 	kfree(mos7840_port);
2456 
2457 	return 0;
2458 }
2459 
2460 static struct usb_serial_driver moschip7840_4port_device = {
2461 	.driver = {
2462 		   .owner = THIS_MODULE,
2463 		   .name = "mos7840",
2464 		   },
2465 	.description = DRIVER_DESC,
2466 	.id_table = id_table,
2467 	.num_ports = 4,
2468 	.open = mos7840_open,
2469 	.close = mos7840_close,
2470 	.write = mos7840_write,
2471 	.write_room = mos7840_write_room,
2472 	.chars_in_buffer = mos7840_chars_in_buffer,
2473 	.throttle = mos7840_throttle,
2474 	.unthrottle = mos7840_unthrottle,
2475 	.calc_num_ports = mos7840_calc_num_ports,
2476 #ifdef MCSSerialProbe
2477 	.probe = mos7840_serial_probe,
2478 #endif
2479 	.ioctl = mos7840_ioctl,
2480 	.set_termios = mos7840_set_termios,
2481 	.break_ctl = mos7840_break,
2482 	.tiocmget = mos7840_tiocmget,
2483 	.tiocmset = mos7840_tiocmset,
2484 	.tiocmiwait = usb_serial_generic_tiocmiwait,
2485 	.get_icount = usb_serial_generic_get_icount,
2486 	.port_probe = mos7840_port_probe,
2487 	.port_remove = mos7840_port_remove,
2488 	.read_bulk_callback = mos7840_bulk_in_callback,
2489 	.read_int_callback = mos7840_interrupt_callback,
2490 };
2491 
2492 static struct usb_serial_driver * const serial_drivers[] = {
2493 	&moschip7840_4port_device, NULL
2494 };
2495 
2496 module_usb_serial_driver(serial_drivers, id_table);
2497 
2498 MODULE_DESCRIPTION(DRIVER_DESC);
2499 MODULE_LICENSE("GPL");
2500