xref: /openbmc/linux/drivers/usb/serial/mos7840.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 <asm/uaccess.h>
37 
38 /*
39  * Version Information
40  */
41 #define DRIVER_VERSION "1.3.1"
42 #define DRIVER_DESC "Moschip 7840/7820 USB Serial Driver"
43 
44 /*
45  * 16C50 UART register defines
46  */
47 
48 #define LCR_BITS_5             0x00	/* 5 bits/char */
49 #define LCR_BITS_6             0x01	/* 6 bits/char */
50 #define LCR_BITS_7             0x02	/* 7 bits/char */
51 #define LCR_BITS_8             0x03	/* 8 bits/char */
52 #define LCR_BITS_MASK          0x03	/* Mask for bits/char field */
53 
54 #define LCR_STOP_1             0x00	/* 1 stop bit */
55 #define LCR_STOP_1_5           0x04	/* 1.5 stop bits (if 5   bits/char) */
56 #define LCR_STOP_2             0x04	/* 2 stop bits   (if 6-8 bits/char) */
57 #define LCR_STOP_MASK          0x04	/* Mask for stop bits field */
58 
59 #define LCR_PAR_NONE           0x00	/* No parity */
60 #define LCR_PAR_ODD            0x08	/* Odd parity */
61 #define LCR_PAR_EVEN           0x18	/* Even parity */
62 #define LCR_PAR_MARK           0x28	/* Force parity bit to 1 */
63 #define LCR_PAR_SPACE          0x38	/* Force parity bit to 0 */
64 #define LCR_PAR_MASK           0x38	/* Mask for parity field */
65 
66 #define LCR_SET_BREAK          0x40	/* Set Break condition */
67 #define LCR_DL_ENABLE          0x80	/* Enable access to divisor latch */
68 
69 #define MCR_DTR                0x01	/* Assert DTR */
70 #define MCR_RTS                0x02	/* Assert RTS */
71 #define MCR_OUT1               0x04	/* Loopback only: Sets state of RI */
72 #define MCR_MASTER_IE          0x08	/* Enable interrupt outputs */
73 #define MCR_LOOPBACK           0x10	/* Set internal (digital) loopback mode */
74 #define MCR_XON_ANY            0x20	/* Enable any char to exit XOFF mode */
75 
76 #define MOS7840_MSR_CTS        0x10	/* Current state of CTS */
77 #define MOS7840_MSR_DSR        0x20	/* Current state of DSR */
78 #define MOS7840_MSR_RI         0x40	/* Current state of RI */
79 #define MOS7840_MSR_CD         0x80	/* Current state of CD */
80 
81 /*
82  * Defines used for sending commands to port
83  */
84 
85 #define WAIT_FOR_EVER   (HZ * 0 )	/* timeout urb is wait for ever */
86 #define MOS_WDR_TIMEOUT (HZ * 5 )	/* default urb timeout */
87 
88 #define MOS_PORT1       0x0200
89 #define MOS_PORT2       0x0300
90 #define MOS_VENREG      0x0000
91 #define MOS_MAX_PORT	0x02
92 #define MOS_WRITE       0x0E
93 #define MOS_READ        0x0D
94 
95 /* Requests */
96 #define MCS_RD_RTYPE    0xC0
97 #define MCS_WR_RTYPE    0x40
98 #define MCS_RDREQ       0x0D
99 #define MCS_WRREQ       0x0E
100 #define MCS_CTRL_TIMEOUT        500
101 #define VENDOR_READ_LENGTH      (0x01)
102 
103 #define MAX_NAME_LEN    64
104 
105 #define ZLP_REG1  0x3A		//Zero_Flag_Reg1    58
106 #define ZLP_REG5  0x3E		//Zero_Flag_Reg5    62
107 
108 /* For higher baud Rates use TIOCEXBAUD */
109 #define TIOCEXBAUD     0x5462
110 
111 /* vendor id and device id defines */
112 
113 #define USB_VENDOR_ID_MOSCHIP           0x9710
114 #define MOSCHIP_DEVICE_ID_7840          0x7840
115 #define MOSCHIP_DEVICE_ID_7820          0x7820
116 
117 /* Interrupt Rotinue Defines    */
118 
119 #define SERIAL_IIR_RLS      0x06
120 #define SERIAL_IIR_MS       0x00
121 
122 /*
123  *  Emulation of the bit mask on the LINE STATUS REGISTER.
124  */
125 #define SERIAL_LSR_DR       0x0001
126 #define SERIAL_LSR_OE       0x0002
127 #define SERIAL_LSR_PE       0x0004
128 #define SERIAL_LSR_FE       0x0008
129 #define SERIAL_LSR_BI       0x0010
130 
131 #define MOS_MSR_DELTA_CTS   0x10
132 #define MOS_MSR_DELTA_DSR   0x20
133 #define MOS_MSR_DELTA_RI    0x40
134 #define MOS_MSR_DELTA_CD    0x80
135 
136 // Serial Port register Address
137 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
138 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
139 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
140 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
141 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
142 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
143 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
144 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
145 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
146 
147 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
148 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
149 
150 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
151 
152 /*
153  * URB POOL related defines
154  */
155 #define NUM_URBS                        16	/* URB Count */
156 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
157 
158 
159 static struct usb_device_id moschip_port_id_table[] = {
160 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
161 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
162 	{}			/* terminating entry */
163 };
164 
165 static __devinitdata struct usb_device_id moschip_id_table_combined[] = {
166 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
167 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
168 	{}			/* terminating entry */
169 };
170 
171 MODULE_DEVICE_TABLE(usb, moschip_id_table_combined);
172 
173 /* This structure holds all of the local port information */
174 
175 struct moschip_port {
176 	int port_num;		/*Actual port number in the device(1,2,etc) */
177 	struct urb *write_urb;	/* write URB for this port */
178 	struct urb *read_urb;	/* read URB for this port */
179 	struct urb *int_urb;
180 	__u8 shadowLCR;		/* last LCR value received */
181 	__u8 shadowMCR;		/* last MCR value received */
182 	char open;
183 	char open_ports;
184 	char zombie;
185 	wait_queue_head_t wait_chase;	/* for handling sleeping while waiting for chase to finish */
186 	wait_queue_head_t delta_msr_wait;	/* for handling sleeping while waiting for msr change to happen */
187 	int delta_msr_cond;
188 	struct async_icount icount;
189 	struct usb_serial_port *port;	/* loop back to the owner of this object */
190 
191 	/*Offsets */
192 	__u8 SpRegOffset;
193 	__u8 ControlRegOffset;
194 	__u8 DcrRegOffset;
195 	//for processing control URBS in interrupt context
196 	struct urb *control_urb;
197 	struct usb_ctrlrequest *dr;
198 	char *ctrl_buf;
199 	int MsrLsr;
200 
201 	spinlock_t pool_lock;
202 	struct urb *write_urb_pool[NUM_URBS];
203 	char busy[NUM_URBS];
204 };
205 
206 
207 static int debug;
208 
209 /*
210  * mos7840_set_reg_sync
211  * 	To set the Control register by calling usb_fill_control_urb function
212  *	by passing usb_sndctrlpipe function as parameter.
213  */
214 
215 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
216 				__u16 val)
217 {
218 	struct usb_device *dev = port->serial->dev;
219 	val = val & 0x00ff;
220 	dbg("mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
221 
222 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
223 			       MCS_WR_RTYPE, val, reg, NULL, 0,
224 			       MOS_WDR_TIMEOUT);
225 }
226 
227 /*
228  * mos7840_get_reg_sync
229  * 	To set the Uart register by calling usb_fill_control_urb function by
230  *	passing usb_rcvctrlpipe function as parameter.
231  */
232 
233 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
234 				__u16 * val)
235 {
236 	struct usb_device *dev = port->serial->dev;
237 	int ret = 0;
238 
239 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
240 			      MCS_RD_RTYPE, 0, reg, val, VENDOR_READ_LENGTH,
241 			      MOS_WDR_TIMEOUT);
242 	dbg("mos7840_get_reg_sync offset is %x, return val %x\n", reg, *val);
243 	*val = (*val) & 0x00ff;
244 	return ret;
245 }
246 
247 /*
248  * mos7840_set_uart_reg
249  *	To set the Uart register by calling usb_fill_control_urb function by
250  *	passing usb_sndctrlpipe function as parameter.
251  */
252 
253 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
254 				__u16 val)
255 {
256 
257 	struct usb_device *dev = port->serial->dev;
258 	val = val & 0x00ff;
259 	// For the UART control registers, the application number need to be Or'ed
260 	if (port->serial->num_ports == 4) {
261 		val |=
262 		    (((__u16) port->number - (__u16) (port->serial->minor)) +
263 		     1) << 8;
264 		dbg("mos7840_set_uart_reg application number is %x\n", val);
265 	} else {
266 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
267 			val |=
268 			    (((__u16) port->number -
269 			      (__u16) (port->serial->minor)) + 1) << 8;
270 			dbg("mos7840_set_uart_reg application number is %x\n",
271 			    val);
272 		} else {
273 			val |=
274 			    (((__u16) port->number -
275 			      (__u16) (port->serial->minor)) + 2) << 8;
276 			dbg("mos7840_set_uart_reg application number is %x\n",
277 			    val);
278 		}
279 	}
280 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
281 			       MCS_WR_RTYPE, val, reg, NULL, 0,
282 			       MOS_WDR_TIMEOUT);
283 
284 }
285 
286 /*
287  * mos7840_get_uart_reg
288  *	To set the Control register by calling usb_fill_control_urb function
289  *	by passing usb_rcvctrlpipe function as parameter.
290  */
291 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
292 				__u16 * val)
293 {
294 	struct usb_device *dev = port->serial->dev;
295 	int ret = 0;
296 	__u16 Wval;
297 
298 	//dbg("application number is %4x \n",(((__u16)port->number - (__u16)(port->serial->minor))+1)<<8);
299 	/*Wval  is same as application number */
300 	if (port->serial->num_ports == 4) {
301 		Wval =
302 		    (((__u16) port->number - (__u16) (port->serial->minor)) +
303 		     1) << 8;
304 		dbg("mos7840_get_uart_reg application number is %x\n", Wval);
305 	} else {
306 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
307 			Wval =
308 			    (((__u16) port->number -
309 			      (__u16) (port->serial->minor)) + 1) << 8;
310 			dbg("mos7840_get_uart_reg application number is %x\n",
311 			    Wval);
312 		} else {
313 			Wval =
314 			    (((__u16) port->number -
315 			      (__u16) (port->serial->minor)) + 2) << 8;
316 			dbg("mos7840_get_uart_reg application number is %x\n",
317 			    Wval);
318 		}
319 	}
320 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
321 			      MCS_RD_RTYPE, Wval, reg, val, VENDOR_READ_LENGTH,
322 			      MOS_WDR_TIMEOUT);
323 	*val = (*val) & 0x00ff;
324 	return ret;
325 }
326 
327 static void mos7840_dump_serial_port(struct moschip_port *mos7840_port)
328 {
329 
330 	dbg("***************************************\n");
331 	dbg("SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
332 	dbg("ControlRegOffset is %2x \n", mos7840_port->ControlRegOffset);
333 	dbg("DCRRegOffset is %2x \n", mos7840_port->DcrRegOffset);
334 	dbg("***************************************\n");
335 
336 }
337 
338 /************************************************************************/
339 /************************************************************************/
340 /*             I N T E R F A C E   F U N C T I O N S			*/
341 /*             I N T E R F A C E   F U N C T I O N S			*/
342 /************************************************************************/
343 /************************************************************************/
344 
345 static inline void mos7840_set_port_private(struct usb_serial_port *port,
346 					    struct moschip_port *data)
347 {
348 	usb_set_serial_port_data(port, (void *)data);
349 }
350 
351 static inline struct moschip_port *mos7840_get_port_private(struct
352 							    usb_serial_port
353 							    *port)
354 {
355 	return (struct moschip_port *)usb_get_serial_port_data(port);
356 }
357 
358 static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
359 {
360 	struct moschip_port *mos7840_port;
361 	struct async_icount *icount;
362 	mos7840_port = port;
363 	icount = &mos7840_port->icount;
364 	if (new_msr &
365 	    (MOS_MSR_DELTA_CTS | MOS_MSR_DELTA_DSR | MOS_MSR_DELTA_RI |
366 	     MOS_MSR_DELTA_CD)) {
367 		icount = &mos7840_port->icount;
368 
369 		/* update input line counters */
370 		if (new_msr & MOS_MSR_DELTA_CTS) {
371 			icount->cts++;
372 			smp_wmb();
373 		}
374 		if (new_msr & MOS_MSR_DELTA_DSR) {
375 			icount->dsr++;
376 			smp_wmb();
377 		}
378 		if (new_msr & MOS_MSR_DELTA_CD) {
379 			icount->dcd++;
380 			smp_wmb();
381 		}
382 		if (new_msr & MOS_MSR_DELTA_RI) {
383 			icount->rng++;
384 			smp_wmb();
385 		}
386 	}
387 }
388 
389 static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)
390 {
391 	struct async_icount *icount;
392 
393 	dbg("%s - %02x", __FUNCTION__, new_lsr);
394 
395 	if (new_lsr & SERIAL_LSR_BI) {
396 		//
397 		// Parity and Framing errors only count if they
398 		// occur exclusive of a break being
399 		// received.
400 		//
401 		new_lsr &= (__u8) (SERIAL_LSR_OE | SERIAL_LSR_BI);
402 	}
403 
404 	/* update input line counters */
405 	icount = &port->icount;
406 	if (new_lsr & SERIAL_LSR_BI) {
407 		icount->brk++;
408 		smp_wmb();
409 	}
410 	if (new_lsr & SERIAL_LSR_OE) {
411 		icount->overrun++;
412 		smp_wmb();
413 	}
414 	if (new_lsr & SERIAL_LSR_PE) {
415 		icount->parity++;
416 		smp_wmb();
417 	}
418 	if (new_lsr & SERIAL_LSR_FE) {
419 		icount->frame++;
420 		smp_wmb();
421 	}
422 }
423 
424 /************************************************************************/
425 /************************************************************************/
426 /*            U S B  C A L L B A C K   F U N C T I O N S                */
427 /*            U S B  C A L L B A C K   F U N C T I O N S                */
428 /************************************************************************/
429 /************************************************************************/
430 
431 static void mos7840_control_callback(struct urb *urb)
432 {
433 	unsigned char *data;
434 	struct moschip_port *mos7840_port;
435 	__u8 regval = 0x0;
436 	int result = 0;
437 	int status = urb->status;
438 
439 	mos7840_port = (struct moschip_port *)urb->context;
440 
441 	switch (status) {
442 	case 0:
443 		/* success */
444 		break;
445 	case -ECONNRESET:
446 	case -ENOENT:
447 	case -ESHUTDOWN:
448 		/* this urb is terminated, clean up */
449 		dbg("%s - urb shutting down with status: %d", __FUNCTION__,
450 		    status);
451 		return;
452 	default:
453 		dbg("%s - nonzero urb status received: %d", __FUNCTION__,
454 		    status);
455 		goto exit;
456 	}
457 
458 	dbg("%s urb buffer size is %d\n", __FUNCTION__, urb->actual_length);
459 	dbg("%s mos7840_port->MsrLsr is %d port %d\n", __FUNCTION__,
460 	    mos7840_port->MsrLsr, mos7840_port->port_num);
461 	data = urb->transfer_buffer;
462 	regval = (__u8) data[0];
463 	dbg("%s data is %x\n", __FUNCTION__, regval);
464 	if (mos7840_port->MsrLsr == 0)
465 		mos7840_handle_new_msr(mos7840_port, regval);
466 	else if (mos7840_port->MsrLsr == 1)
467 		mos7840_handle_new_lsr(mos7840_port, regval);
468 
469 exit:
470 	spin_lock(&mos7840_port->pool_lock);
471 	if (!mos7840_port->zombie)
472 		result = usb_submit_urb(mos7840_port->int_urb, GFP_ATOMIC);
473 	spin_unlock(&mos7840_port->pool_lock);
474 	if (result) {
475 		dev_err(&urb->dev->dev,
476 			"%s - Error %d submitting interrupt urb\n",
477 			__FUNCTION__, result);
478 	}
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 /*****************************************************************************
504  * mos7840_interrupt_callback
505  *	this is the callback function for when we have received data on the
506  *	interrupt endpoint.
507  *****************************************************************************/
508 
509 static void mos7840_interrupt_callback(struct urb *urb)
510 {
511 	int result;
512 	int length;
513 	struct moschip_port *mos7840_port;
514 	struct usb_serial *serial;
515 	__u16 Data;
516 	unsigned char *data;
517 	__u8 sp[5], st;
518 	int i, rv = 0;
519 	__u16 wval, wreg = 0;
520 	int status = urb->status;
521 
522 	dbg("%s", " : Entering\n");
523 
524 	switch (status) {
525 	case 0:
526 		/* success */
527 		break;
528 	case -ECONNRESET:
529 	case -ENOENT:
530 	case -ESHUTDOWN:
531 		/* this urb is terminated, clean up */
532 		dbg("%s - urb shutting down with status: %d", __FUNCTION__,
533 		    status);
534 		return;
535 	default:
536 		dbg("%s - nonzero urb status received: %d", __FUNCTION__,
537 		    status);
538 		goto exit;
539 	}
540 
541 	length = urb->actual_length;
542 	data = urb->transfer_buffer;
543 
544 	serial = (struct usb_serial *)urb->context;
545 
546 	/* Moschip get 5 bytes
547 	 * Byte 1 IIR Port 1 (port.number is 0)
548 	 * Byte 2 IIR Port 2 (port.number is 1)
549 	 * Byte 3 IIR Port 3 (port.number is 2)
550 	 * Byte 4 IIR Port 4 (port.number is 3)
551 	 * Byte 5 FIFO status for both */
552 
553 	if (length && length > 5) {
554 		dbg("%s \n", "Wrong data !!!");
555 		return;
556 	}
557 
558 	sp[0] = (__u8) data[0];
559 	sp[1] = (__u8) data[1];
560 	sp[2] = (__u8) data[2];
561 	sp[3] = (__u8) data[3];
562 	st = (__u8) data[4];
563 
564 	for (i = 0; i < serial->num_ports; i++) {
565 		mos7840_port = mos7840_get_port_private(serial->port[i]);
566 		wval =
567 		    (((__u16) serial->port[i]->number -
568 		      (__u16) (serial->minor)) + 1) << 8;
569 		if (mos7840_port->open) {
570 			if (sp[i] & 0x01) {
571 				dbg("SP%d No Interrupt !!!\n", i);
572 			} else {
573 				switch (sp[i] & 0x0f) {
574 				case SERIAL_IIR_RLS:
575 					dbg("Serial Port %d: Receiver status error or ", i);
576 					dbg("address bit detected in 9-bit mode\n");
577 					mos7840_port->MsrLsr = 1;
578 					wreg = LINE_STATUS_REGISTER;
579 					break;
580 				case SERIAL_IIR_MS:
581 					dbg("Serial Port %d: Modem status change\n", i);
582 					mos7840_port->MsrLsr = 0;
583 					wreg = MODEM_STATUS_REGISTER;
584 					break;
585 				}
586 				spin_lock(&mos7840_port->pool_lock);
587 				if (!mos7840_port->zombie) {
588 					rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
589 				} else {
590 					spin_unlock(&mos7840_port->pool_lock);
591 					return;
592 				}
593 				spin_unlock(&mos7840_port->pool_lock);
594 			}
595 		}
596 	}
597 	if (!(rv < 0)) /* the completion handler for the control urb will resubmit */
598 		return;
599 exit:
600 	result = usb_submit_urb(urb, GFP_ATOMIC);
601 	if (result) {
602 		dev_err(&urb->dev->dev,
603 			"%s - Error %d submitting interrupt urb\n",
604 			__FUNCTION__, result);
605 	}
606 }
607 
608 static int mos7840_port_paranoia_check(struct usb_serial_port *port,
609 				       const char *function)
610 {
611 	if (!port) {
612 		dbg("%s - port == NULL", function);
613 		return -1;
614 	}
615 	if (!port->serial) {
616 		dbg("%s - port->serial == NULL", function);
617 		return -1;
618 	}
619 
620 	return 0;
621 }
622 
623 /* Inline functions to check the sanity of a pointer that is passed to us */
624 static int mos7840_serial_paranoia_check(struct usb_serial *serial,
625 					 const char *function)
626 {
627 	if (!serial) {
628 		dbg("%s - serial == NULL", function);
629 		return -1;
630 	}
631 	if (!serial->type) {
632 		dbg("%s - serial->type == NULL!", function);
633 		return -1;
634 	}
635 
636 	return 0;
637 }
638 
639 static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
640 						 const char *function)
641 {
642 	/* if no port was specified, or it fails a paranoia check */
643 	if (!port ||
644 	    mos7840_port_paranoia_check(port, function) ||
645 	    mos7840_serial_paranoia_check(port->serial, function)) {
646 		/* then say that we don't have a valid usb_serial thing, which will
647 		 * end up genrating -ENODEV return values */
648 		return NULL;
649 	}
650 
651 	return port->serial;
652 }
653 
654 /*****************************************************************************
655  * mos7840_bulk_in_callback
656  *	this is the callback function for when we have received data on the
657  *	bulk in endpoint.
658  *****************************************************************************/
659 
660 static void mos7840_bulk_in_callback(struct urb *urb)
661 {
662 	int retval;
663 	unsigned char *data;
664 	struct usb_serial *serial;
665 	struct usb_serial_port *port;
666 	struct moschip_port *mos7840_port;
667 	struct tty_struct *tty;
668 	int status = urb->status;
669 
670 	if (status) {
671 		dbg("nonzero read bulk status received: %d", status);
672 		return;
673 	}
674 
675 	mos7840_port = (struct moschip_port *)urb->context;
676 	if (!mos7840_port) {
677 		dbg("%s", "NULL mos7840_port pointer \n");
678 		return;
679 	}
680 
681 	port = (struct usb_serial_port *)mos7840_port->port;
682 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
683 		dbg("%s", "Port Paranoia failed \n");
684 		return;
685 	}
686 
687 	serial = mos7840_get_usb_serial(port, __FUNCTION__);
688 	if (!serial) {
689 		dbg("%s\n", "Bad serial pointer ");
690 		return;
691 	}
692 
693 	dbg("%s\n", "Entering... \n");
694 
695 	data = urb->transfer_buffer;
696 
697 	dbg("%s", "Entering ........... \n");
698 
699 	if (urb->actual_length) {
700 		tty = mos7840_port->port->tty;
701 		if (tty) {
702 			tty_buffer_request_room(tty, urb->actual_length);
703 			tty_insert_flip_string(tty, data, urb->actual_length);
704 			dbg(" %s \n", data);
705 			tty_flip_buffer_push(tty);
706 		}
707 		mos7840_port->icount.rx += urb->actual_length;
708 		smp_wmb();
709 		dbg("mos7840_port->icount.rx is %d:\n",
710 		    mos7840_port->icount.rx);
711 	}
712 
713 	if (!mos7840_port->read_urb) {
714 		dbg("%s", "URB KILLED !!!\n");
715 		return;
716 	}
717 
718 
719 	mos7840_port->read_urb->dev = serial->dev;
720 
721 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
722 
723 	if (retval) {
724 		dbg(" usb_submit_urb(read bulk) failed, retval = %d",
725 		 retval);
726 	}
727 }
728 
729 /*****************************************************************************
730  * mos7840_bulk_out_data_callback
731  *	this is the callback function for when we have finished sending serial data
732  *	on the bulk out endpoint.
733  *****************************************************************************/
734 
735 static void mos7840_bulk_out_data_callback(struct urb *urb)
736 {
737 	struct moschip_port *mos7840_port;
738 	struct tty_struct *tty;
739 	int status = urb->status;
740 	int i;
741 
742 	mos7840_port = (struct moschip_port *)urb->context;
743 	spin_lock(&mos7840_port->pool_lock);
744 	for (i = 0; i < NUM_URBS; i++) {
745 		if (urb == mos7840_port->write_urb_pool[i]) {
746 			mos7840_port->busy[i] = 0;
747 			break;
748 		}
749 	}
750 	spin_unlock(&mos7840_port->pool_lock);
751 
752 	if (status) {
753 		dbg("nonzero write bulk status received:%d\n", status);
754 		return;
755 	}
756 
757 	if (mos7840_port_paranoia_check(mos7840_port->port, __FUNCTION__)) {
758 		dbg("%s", "Port Paranoia failed \n");
759 		return;
760 	}
761 
762 	dbg("%s \n", "Entering .........");
763 
764 	tty = mos7840_port->port->tty;
765 
766 	if (tty && mos7840_port->open)
767 		tty_wakeup(tty);
768 
769 }
770 
771 /************************************************************************/
772 /*       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       */
773 /************************************************************************/
774 #ifdef MCSSerialProbe
775 static int mos7840_serial_probe(struct usb_serial *serial,
776 				const struct usb_device_id *id)
777 {
778 
779 	/*need to implement the mode_reg reading and updating\
780 	   structures usb_serial_ device_type\
781 	   (i.e num_ports, num_bulkin,bulkout etc) */
782 	/* Also we can update the changes  attach */
783 	return 1;
784 }
785 #endif
786 
787 /*****************************************************************************
788  * mos7840_open
789  *	this function is called by the tty driver when a port is opened
790  *	If successful, we return 0
791  *	Otherwise we return a negative error number.
792  *****************************************************************************/
793 
794 static int mos7840_open(struct usb_serial_port *port, struct file *filp)
795 {
796 	int response;
797 	int j;
798 	struct usb_serial *serial;
799 	struct urb *urb;
800 	__u16 Data;
801 	int status;
802 	struct moschip_port *mos7840_port;
803 	struct moschip_port *port0;
804 
805 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
806 		dbg("%s", "Port Paranoia failed \n");
807 		return -ENODEV;
808 	}
809 
810 	serial = port->serial;
811 
812 	if (mos7840_serial_paranoia_check(serial, __FUNCTION__)) {
813 		dbg("%s", "Serial Paranoia failed \n");
814 		return -ENODEV;
815 	}
816 
817 	mos7840_port = mos7840_get_port_private(port);
818 	port0 = mos7840_get_port_private(serial->port[0]);
819 
820 	if (mos7840_port == NULL || port0 == NULL)
821 		return -ENODEV;
822 
823 	usb_clear_halt(serial->dev, port->write_urb->pipe);
824 	usb_clear_halt(serial->dev, port->read_urb->pipe);
825 	port0->open_ports++;
826 
827 	/* Initialising the write urb pool */
828 	for (j = 0; j < NUM_URBS; ++j) {
829 		urb = usb_alloc_urb(0, GFP_KERNEL);
830 		mos7840_port->write_urb_pool[j] = urb;
831 
832 		if (urb == NULL) {
833 			err("No more urbs???");
834 			continue;
835 		}
836 
837 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
838 		if (!urb->transfer_buffer) {
839 			usb_free_urb(urb);
840 			mos7840_port->write_urb_pool[j] = NULL;
841 			err("%s-out of memory for urb buffers.", __FUNCTION__);
842 			continue;
843 		}
844 	}
845 
846 /*****************************************************************************
847  * Initialize MCS7840 -- Write Init values to corresponding Registers
848  *
849  * Register Index
850  * 1 : IER
851  * 2 : FCR
852  * 3 : LCR
853  * 4 : MCR
854  *
855  * 0x08 : SP1/2 Control Reg
856  *****************************************************************************/
857 
858 //NEED to check the following Block
859 
860 	status = 0;
861 	Data = 0x0;
862 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
863 	if (status < 0) {
864 		dbg("Reading Spreg failed\n");
865 		return -1;
866 	}
867 	Data |= 0x80;
868 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
869 	if (status < 0) {
870 		dbg("writing Spreg failed\n");
871 		return -1;
872 	}
873 
874 	Data &= ~0x80;
875 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
876 	if (status < 0) {
877 		dbg("writing Spreg failed\n");
878 		return -1;
879 	}
880 //End of block to be checked
881 
882 	status = 0;
883 	Data = 0x0;
884 	status =
885 	    mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset, &Data);
886 	if (status < 0) {
887 		dbg("Reading Controlreg failed\n");
888 		return -1;
889 	}
890 	Data |= 0x08;		//Driver done bit
891 	Data |= 0x20;		//rx_disable
892 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset, Data);
893 	if (status < 0) {
894 		dbg("writing Controlreg failed\n");
895 		return -1;
896 	}
897 	//do register settings here
898 	// Set all regs to the device default values.
899 	////////////////////////////////////
900 	// First Disable all interrupts.
901 	////////////////////////////////////
902 
903 	Data = 0x00;
904 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
905 	if (status < 0) {
906 		dbg("disableing interrupts failed\n");
907 		return -1;
908 	}
909 	// Set FIFO_CONTROL_REGISTER to the default value
910 	Data = 0x00;
911 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
912 	if (status < 0) {
913 		dbg("Writing FIFO_CONTROL_REGISTER  failed\n");
914 		return -1;
915 	}
916 
917 	Data = 0xcf;
918 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
919 	if (status < 0) {
920 		dbg("Writing FIFO_CONTROL_REGISTER  failed\n");
921 		return -1;
922 	}
923 
924 	Data = 0x03;
925 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
926 	mos7840_port->shadowLCR = Data;
927 
928 	Data = 0x0b;
929 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
930 	mos7840_port->shadowMCR = Data;
931 
932 	Data = 0x00;
933 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
934 	mos7840_port->shadowLCR = Data;
935 
936 	Data |= SERIAL_LCR_DLAB;	//data latch enable in LCR 0x80
937 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
938 
939 	Data = 0x0c;
940 	status = 0;
941 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
942 
943 	Data = 0x0;
944 	status = 0;
945 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
946 
947 	Data = 0x00;
948 	status = 0;
949 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
950 
951 	Data = Data & ~SERIAL_LCR_DLAB;
952 	status = 0;
953 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
954 	mos7840_port->shadowLCR = Data;
955 
956 	//clearing Bulkin and Bulkout Fifo
957 	Data = 0x0;
958 	status = 0;
959 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
960 
961 	Data = Data | 0x0c;
962 	status = 0;
963 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
964 
965 	Data = Data & ~0x0c;
966 	status = 0;
967 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
968 	//Finally enable all interrupts
969 	Data = 0x0;
970 	Data = 0x0c;
971 	status = 0;
972 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
973 
974 	//clearing rx_disable
975 	Data = 0x0;
976 	status = 0;
977 	status =
978 	    mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset, &Data);
979 	Data = Data & ~0x20;
980 	status = 0;
981 	status =
982 	    mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset, Data);
983 
984 	// rx_negate
985 	Data = 0x0;
986 	status = 0;
987 	status =
988 	    mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset, &Data);
989 	Data = Data | 0x10;
990 	status = 0;
991 	status =
992 	    mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset, Data);
993 
994 	/* force low_latency on so that our tty_push actually forces *
995 	 * the data through,otherwise it is scheduled, and with      *
996 	 * high data rates (like with OHCI) data can get lost.       */
997 
998 	if (port->tty)
999 		port->tty->low_latency = 1;
1000 /* Check to see if we've set up our endpoint info yet    *
1001      * (can't set it up in mos7840_startup as the structures *
1002      * were not set up at that time.)                        */
1003 	if (port0->open_ports == 1) {
1004 		if (serial->port[0]->interrupt_in_buffer == NULL) {
1005 
1006 			/* set up interrupt urb */
1007 
1008 			usb_fill_int_urb(serial->port[0]->interrupt_in_urb,
1009 					 serial->dev,
1010 					 usb_rcvintpipe(serial->dev,
1011 							serial->port[0]->
1012 							interrupt_in_endpointAddress),
1013 					 serial->port[0]->interrupt_in_buffer,
1014 					 serial->port[0]->interrupt_in_urb->
1015 					 transfer_buffer_length,
1016 					 mos7840_interrupt_callback,
1017 					 serial,
1018 					 serial->port[0]->interrupt_in_urb->
1019 					 interval);
1020 
1021 			/* start interrupt read for mos7840               *
1022 			 * will continue as long as mos7840 is connected  */
1023 
1024 			response =
1025 			    usb_submit_urb(serial->port[0]->interrupt_in_urb,
1026 					   GFP_KERNEL);
1027 			if (response) {
1028 				err("%s - Error %d submitting interrupt urb",
1029 				    __FUNCTION__, response);
1030 			}
1031 
1032 		}
1033 
1034 	}
1035 
1036 	/* see if we've set up our endpoint info yet   *
1037 	 * (can't set it up in mos7840_startup as the  *
1038 	 * structures were not set up at that time.)   */
1039 
1040 	dbg("port number is %d \n", port->number);
1041 	dbg("serial number is %d \n", port->serial->minor);
1042 	dbg("Bulkin endpoint is %d \n", port->bulk_in_endpointAddress);
1043 	dbg("BulkOut endpoint is %d \n", port->bulk_out_endpointAddress);
1044 	dbg("Interrupt endpoint is %d \n", port->interrupt_in_endpointAddress);
1045 	dbg("port's number in the device is %d\n", mos7840_port->port_num);
1046 	mos7840_port->read_urb = port->read_urb;
1047 
1048 	/* set up our bulk in urb */
1049 
1050 	usb_fill_bulk_urb(mos7840_port->read_urb,
1051 			  serial->dev,
1052 			  usb_rcvbulkpipe(serial->dev,
1053 					  port->bulk_in_endpointAddress),
1054 			  port->bulk_in_buffer,
1055 			  mos7840_port->read_urb->transfer_buffer_length,
1056 			  mos7840_bulk_in_callback, mos7840_port);
1057 
1058 	dbg("mos7840_open: bulkin endpoint is %d\n",
1059 	    port->bulk_in_endpointAddress);
1060 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1061 	if (response) {
1062 		err("%s - Error %d submitting control urb", __FUNCTION__,
1063 		    response);
1064 	}
1065 
1066 	/* initialize our wait queues */
1067 	init_waitqueue_head(&mos7840_port->wait_chase);
1068 	init_waitqueue_head(&mos7840_port->delta_msr_wait);
1069 
1070 	/* initialize our icount structure */
1071 	memset(&(mos7840_port->icount), 0x00, sizeof(mos7840_port->icount));
1072 
1073 	/* initialize our port settings */
1074 	mos7840_port->shadowMCR = MCR_MASTER_IE;	/* Must set to enable ints! */
1075 	/* send a open port command */
1076 	mos7840_port->open = 1;
1077 	//mos7840_change_port_settings(mos7840_port,old_termios);
1078 	mos7840_port->icount.tx = 0;
1079 	mos7840_port->icount.rx = 0;
1080 
1081 	dbg("\n\nusb_serial serial:%p       mos7840_port:%p\n      usb_serial_port port:%p\n\n", serial, mos7840_port, port);
1082 
1083 	return 0;
1084 
1085 }
1086 
1087 /*****************************************************************************
1088  * mos7840_chars_in_buffer
1089  *	this function is called by the tty driver when it wants to know how many
1090  *	bytes of data we currently have outstanding in the port (data that has
1091  *	been written, but hasn't made it out the port yet)
1092  *	If successful, we return the number of bytes left to be written in the
1093  *	system,
1094  *	Otherwise we return a negative error number.
1095  *****************************************************************************/
1096 
1097 static int mos7840_chars_in_buffer(struct usb_serial_port *port)
1098 {
1099 	int i;
1100 	int chars = 0;
1101 	unsigned long flags;
1102 	struct moschip_port *mos7840_port;
1103 
1104 	dbg("%s \n", " mos7840_chars_in_buffer:entering ...........");
1105 
1106 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1107 		dbg("%s", "Invalid port \n");
1108 		return -1;
1109 	}
1110 
1111 	mos7840_port = mos7840_get_port_private(port);
1112 	if (mos7840_port == NULL) {
1113 		dbg("%s \n", "mos7840_break:leaving ...........");
1114 		return -1;
1115 	}
1116 
1117 	spin_lock_irqsave(&mos7840_port->pool_lock,flags);
1118 	for (i = 0; i < NUM_URBS; ++i) {
1119 		if (mos7840_port->busy[i]) {
1120 			chars += URB_TRANSFER_BUFFER_SIZE;
1121 		}
1122 	}
1123 	spin_unlock_irqrestore(&mos7840_port->pool_lock,flags);
1124 	dbg("%s - returns %d", __FUNCTION__, chars);
1125 	return chars;
1126 
1127 }
1128 
1129 /************************************************************************
1130  *
1131  * mos7840_block_until_tx_empty
1132  *
1133  *	This function will block the close until one of the following:
1134  *		1. TX count are 0
1135  *		2. The mos7840 has stopped
1136  *		3. A timout of 3 seconds without activity has expired
1137  *
1138  ************************************************************************/
1139 static void mos7840_block_until_tx_empty(struct moschip_port *mos7840_port)
1140 {
1141 	int timeout = HZ / 10;
1142 	int wait = 30;
1143 	int count;
1144 
1145 	while (1) {
1146 
1147 		count = mos7840_chars_in_buffer(mos7840_port->port);
1148 
1149 		/* Check for Buffer status */
1150 		if (count <= 0) {
1151 			return;
1152 		}
1153 
1154 		/* Block the thread for a while */
1155 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1156 					       timeout);
1157 
1158 		/* No activity.. count down section */
1159 		wait--;
1160 		if (wait == 0) {
1161 			dbg("%s - TIMEOUT", __FUNCTION__);
1162 			return;
1163 		} else {
1164 			/* Reset timout value back to seconds */
1165 			wait = 30;
1166 		}
1167 	}
1168 }
1169 
1170 /*****************************************************************************
1171  * mos7840_close
1172  *	this function is called by the tty driver when a port is closed
1173  *****************************************************************************/
1174 
1175 static void mos7840_close(struct usb_serial_port *port, struct file *filp)
1176 {
1177 	struct usb_serial *serial;
1178 	struct moschip_port *mos7840_port;
1179 	struct moschip_port *port0;
1180 	int j;
1181 	__u16 Data;
1182 
1183 	dbg("%s\n", "mos7840_close:entering...");
1184 
1185 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1186 		dbg("%s", "Port Paranoia failed \n");
1187 		return;
1188 	}
1189 
1190 	serial = mos7840_get_usb_serial(port, __FUNCTION__);
1191 	if (!serial) {
1192 		dbg("%s", "Serial Paranoia failed \n");
1193 		return;
1194 	}
1195 
1196 	mos7840_port = mos7840_get_port_private(port);
1197 	port0 = mos7840_get_port_private(serial->port[0]);
1198 
1199 	if (mos7840_port == NULL || port0 == NULL)
1200 		return;
1201 
1202 	for (j = 0; j < NUM_URBS; ++j)
1203 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
1204 
1205 	/* Freeing Write URBs */
1206 	for (j = 0; j < NUM_URBS; ++j) {
1207 		if (mos7840_port->write_urb_pool[j]) {
1208 			if (mos7840_port->write_urb_pool[j]->transfer_buffer)
1209 				kfree(mos7840_port->write_urb_pool[j]->
1210 				      transfer_buffer);
1211 
1212 			usb_free_urb(mos7840_port->write_urb_pool[j]);
1213 		}
1214 	}
1215 
1216 	if (serial->dev) {
1217 		/* flush and block until tx is empty */
1218 		mos7840_block_until_tx_empty(mos7840_port);
1219 	}
1220 
1221 	/* While closing port, shutdown all bulk read, write  *
1222 	 * and interrupt read if they exists                  */
1223 	if (serial->dev) {
1224 
1225 		if (mos7840_port->write_urb) {
1226 			dbg("%s", "Shutdown bulk write\n");
1227 			usb_kill_urb(mos7840_port->write_urb);
1228 		}
1229 
1230 		if (mos7840_port->read_urb) {
1231 			dbg("%s", "Shutdown bulk read\n");
1232 			usb_kill_urb(mos7840_port->read_urb);
1233 		}
1234 		if ((&mos7840_port->control_urb)) {
1235 			dbg("%s", "Shutdown control read\n");
1236 			//      usb_kill_urb (mos7840_port->control_urb);
1237 
1238 		}
1239 	}
1240 //              if(mos7840_port->ctrl_buf != NULL)
1241 //                      kfree(mos7840_port->ctrl_buf);
1242 	port0->open_ports--;
1243 	dbg("mos7840_num_open_ports in close%d:in port%d\n",
1244 	    port0->open_ports, port->number);
1245 	if (port0->open_ports == 0) {
1246 		if (serial->port[0]->interrupt_in_urb) {
1247 			dbg("%s", "Shutdown interrupt_in_urb\n");
1248 			usb_kill_urb(serial->port[0]->interrupt_in_urb);
1249 		}
1250 	}
1251 
1252 	if (mos7840_port->write_urb) {
1253 		/* if this urb had a transfer buffer already (old tx) free it */
1254 
1255 		if (mos7840_port->write_urb->transfer_buffer != NULL) {
1256 			kfree(mos7840_port->write_urb->transfer_buffer);
1257 		}
1258 		usb_free_urb(mos7840_port->write_urb);
1259 	}
1260 
1261 	Data = 0x0;
1262 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1263 
1264 	Data = 0x00;
1265 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1266 
1267 	mos7840_port->open = 0;
1268 
1269 	dbg("%s \n", "Leaving ............");
1270 }
1271 
1272 /************************************************************************
1273  *
1274  * mos7840_block_until_chase_response
1275  *
1276  *	This function will block the close until one of the following:
1277  *		1. Response to our Chase comes from mos7840
1278  *		2. A timout of 10 seconds without activity has expired
1279  *		   (1K of mos7840 data @ 2400 baud ==> 4 sec to empty)
1280  *
1281  ************************************************************************/
1282 
1283 static void mos7840_block_until_chase_response(struct moschip_port
1284 					       *mos7840_port)
1285 {
1286 	int timeout = 1 * HZ;
1287 	int wait = 10;
1288 	int count;
1289 
1290 	while (1) {
1291 		count = mos7840_chars_in_buffer(mos7840_port->port);
1292 
1293 		/* Check for Buffer status */
1294 		if (count <= 0) {
1295 			return;
1296 		}
1297 
1298 		/* Block the thread for a while */
1299 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1300 					       timeout);
1301 		/* No activity.. count down section */
1302 		wait--;
1303 		if (wait == 0) {
1304 			dbg("%s - TIMEOUT", __FUNCTION__);
1305 			return;
1306 		} else {
1307 			/* Reset timout value back to seconds */
1308 			wait = 10;
1309 		}
1310 	}
1311 
1312 }
1313 
1314 /*****************************************************************************
1315  * mos7840_break
1316  *	this function sends a break to the port
1317  *****************************************************************************/
1318 static void mos7840_break(struct usb_serial_port *port, int break_state)
1319 {
1320 	unsigned char data;
1321 	struct usb_serial *serial;
1322 	struct moschip_port *mos7840_port;
1323 
1324 	dbg("%s \n", "Entering ...........");
1325 	dbg("mos7840_break: Start\n");
1326 
1327 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1328 		dbg("%s", "Port Paranoia failed \n");
1329 		return;
1330 	}
1331 
1332 	serial = mos7840_get_usb_serial(port, __FUNCTION__);
1333 	if (!serial) {
1334 		dbg("%s", "Serial Paranoia failed \n");
1335 		return;
1336 	}
1337 
1338 	mos7840_port = mos7840_get_port_private(port);
1339 
1340 	if (mos7840_port == NULL) {
1341 		return;
1342 	}
1343 
1344 	if (serial->dev) {
1345 
1346 		/* flush and block until tx is empty */
1347 		mos7840_block_until_chase_response(mos7840_port);
1348 	}
1349 
1350 	if (break_state == -1) {
1351 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
1352 	} else {
1353 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
1354 	}
1355 
1356 	mos7840_port->shadowLCR = data;
1357 	dbg("mcs7840_break mos7840_port->shadowLCR is %x\n",
1358 	    mos7840_port->shadowLCR);
1359 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
1360 			     mos7840_port->shadowLCR);
1361 
1362 	return;
1363 }
1364 
1365 /*****************************************************************************
1366  * mos7840_write_room
1367  *	this function is called by the tty driver when it wants to know how many
1368  *	bytes of data we can accept for a specific port.
1369  *	If successful, we return the amount of room that we have for this port
1370  *	Otherwise we return a negative error number.
1371  *****************************************************************************/
1372 
1373 static int mos7840_write_room(struct usb_serial_port *port)
1374 {
1375 	int i;
1376 	int room = 0;
1377 	unsigned long flags;
1378 	struct moschip_port *mos7840_port;
1379 
1380 	dbg("%s \n", " mos7840_write_room:entering ...........");
1381 
1382 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1383 		dbg("%s", "Invalid port \n");
1384 		dbg("%s \n", " mos7840_write_room:leaving ...........");
1385 		return -1;
1386 	}
1387 
1388 	mos7840_port = mos7840_get_port_private(port);
1389 	if (mos7840_port == NULL) {
1390 		dbg("%s \n", "mos7840_break:leaving ...........");
1391 		return -1;
1392 	}
1393 
1394 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1395 	for (i = 0; i < NUM_URBS; ++i) {
1396 		if (!mos7840_port->busy[i]) {
1397 			room += URB_TRANSFER_BUFFER_SIZE;
1398 		}
1399 	}
1400 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1401 
1402 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
1403 	dbg("%s - returns %d", __FUNCTION__, room);
1404 	return room;
1405 
1406 }
1407 
1408 /*****************************************************************************
1409  * mos7840_write
1410  *	this function is called by the tty driver when data should be written to
1411  *	the port.
1412  *	If successful, we return the number of bytes written, otherwise we
1413  *      return a negative error number.
1414  *****************************************************************************/
1415 
1416 static int mos7840_write(struct usb_serial_port *port,
1417 			 const unsigned char *data, int count)
1418 {
1419 	int status;
1420 	int i;
1421 	int bytes_sent = 0;
1422 	int transfer_size;
1423 	unsigned long flags;
1424 
1425 	struct moschip_port *mos7840_port;
1426 	struct usb_serial *serial;
1427 	struct urb *urb;
1428 	//__u16 Data;
1429 	const unsigned char *current_position = data;
1430 	unsigned char *data1;
1431 	dbg("%s \n", "entering ...........");
1432 	//dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",mos7840_port->shadowLCR);
1433 
1434 #ifdef NOTMOS7840
1435 	Data = 0x00;
1436 	status = 0;
1437 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1438 	mos7840_port->shadowLCR = Data;
1439 	dbg("mos7840_write: LINE_CONTROL_REGISTER is %x\n", Data);
1440 	dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
1441 	    mos7840_port->shadowLCR);
1442 
1443 	//Data = 0x03;
1444 	//status = mos7840_set_uart_reg(port,LINE_CONTROL_REGISTER,Data);
1445 	//mos7840_port->shadowLCR=Data;//Need to add later
1446 
1447 	Data |= SERIAL_LCR_DLAB;	//data latch enable in LCR 0x80
1448 	status = 0;
1449 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1450 
1451 	//Data = 0x0c;
1452 	//status = mos7840_set_uart_reg(port,DIVISOR_LATCH_LSB,Data);
1453 	Data = 0x00;
1454 	status = 0;
1455 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_LSB, &Data);
1456 	dbg("mos7840_write:DLL value is %x\n", Data);
1457 
1458 	Data = 0x0;
1459 	status = 0;
1460 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_MSB, &Data);
1461 	dbg("mos7840_write:DLM value is %x\n", Data);
1462 
1463 	Data = Data & ~SERIAL_LCR_DLAB;
1464 	dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
1465 	    mos7840_port->shadowLCR);
1466 	status = 0;
1467 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1468 #endif
1469 
1470 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1471 		dbg("%s", "Port Paranoia failed \n");
1472 		return -1;
1473 	}
1474 
1475 	serial = port->serial;
1476 	if (mos7840_serial_paranoia_check(serial, __FUNCTION__)) {
1477 		dbg("%s", "Serial Paranoia failed \n");
1478 		return -1;
1479 	}
1480 
1481 	mos7840_port = mos7840_get_port_private(port);
1482 	if (mos7840_port == NULL) {
1483 		dbg("%s", "mos7840_port is NULL\n");
1484 		return -1;
1485 	}
1486 
1487 	/* try to find a free urb in the list */
1488 	urb = NULL;
1489 
1490 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1491 	for (i = 0; i < NUM_URBS; ++i) {
1492 		if (!mos7840_port->busy[i]) {
1493 			mos7840_port->busy[i] = 1;
1494 			urb = mos7840_port->write_urb_pool[i];
1495 			dbg("\nURB:%d", i);
1496 			break;
1497 		}
1498 	}
1499 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1500 
1501 	if (urb == NULL) {
1502 		dbg("%s - no more free urbs", __FUNCTION__);
1503 		goto exit;
1504 	}
1505 
1506 	if (urb->transfer_buffer == NULL) {
1507 		urb->transfer_buffer =
1508 		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
1509 
1510 		if (urb->transfer_buffer == NULL) {
1511 			err("%s no more kernel memory...", __FUNCTION__);
1512 			goto exit;
1513 		}
1514 	}
1515 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1516 
1517 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1518 
1519 	/* fill urb with data and submit  */
1520 	usb_fill_bulk_urb(urb,
1521 			  serial->dev,
1522 			  usb_sndbulkpipe(serial->dev,
1523 					  port->bulk_out_endpointAddress),
1524 			  urb->transfer_buffer,
1525 			  transfer_size,
1526 			  mos7840_bulk_out_data_callback, mos7840_port);
1527 
1528 	data1 = urb->transfer_buffer;
1529 	dbg("\nbulkout endpoint is %d", port->bulk_out_endpointAddress);
1530 
1531 	/* send it down the pipe */
1532 	status = usb_submit_urb(urb, GFP_ATOMIC);
1533 
1534 	if (status) {
1535 		mos7840_port->busy[i] = 0;
1536 		err("%s - usb_submit_urb(write bulk) failed with status = %d",
1537 		    __FUNCTION__, status);
1538 		bytes_sent = status;
1539 		goto exit;
1540 	}
1541 	bytes_sent = transfer_size;
1542 	mos7840_port->icount.tx += transfer_size;
1543 	smp_wmb();
1544 	dbg("mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);
1545       exit:
1546 
1547 	return bytes_sent;
1548 
1549 }
1550 
1551 /*****************************************************************************
1552  * mos7840_throttle
1553  *	this function is called by the tty driver when it wants to stop the data
1554  *	being read from the port.
1555  *****************************************************************************/
1556 
1557 static void mos7840_throttle(struct usb_serial_port *port)
1558 {
1559 	struct moschip_port *mos7840_port;
1560 	struct tty_struct *tty;
1561 	int status;
1562 
1563 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1564 		dbg("%s", "Invalid port \n");
1565 		return;
1566 	}
1567 
1568 	dbg("- port %d\n", port->number);
1569 
1570 	mos7840_port = mos7840_get_port_private(port);
1571 
1572 	if (mos7840_port == NULL)
1573 		return;
1574 
1575 	if (!mos7840_port->open) {
1576 		dbg("%s\n", "port not opened");
1577 		return;
1578 	}
1579 
1580 	dbg("%s", "Entering .......... \n");
1581 
1582 	tty = port->tty;
1583 	if (!tty) {
1584 		dbg("%s - no tty available", __FUNCTION__);
1585 		return;
1586 	}
1587 
1588 	/* if we are implementing XON/XOFF, send the stop character */
1589 	if (I_IXOFF(tty)) {
1590 		unsigned char stop_char = STOP_CHAR(tty);
1591 		status = mos7840_write(port, &stop_char, 1);
1592 		if (status <= 0) {
1593 			return;
1594 		}
1595 	}
1596 
1597 	/* if we are implementing RTS/CTS, toggle that line */
1598 	if (tty->termios->c_cflag & CRTSCTS) {
1599 		mos7840_port->shadowMCR &= ~MCR_RTS;
1600 		status = 0;
1601 		status =
1602 		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1603 					 mos7840_port->shadowMCR);
1604 
1605 		if (status < 0) {
1606 			return;
1607 		}
1608 	}
1609 
1610 	return;
1611 }
1612 
1613 /*****************************************************************************
1614  * mos7840_unthrottle
1615  *	this function is called by the tty driver when it wants to resume the data
1616  *	being read from the port (called after SerialThrottle is called)
1617  *****************************************************************************/
1618 static void mos7840_unthrottle(struct usb_serial_port *port)
1619 {
1620 	struct tty_struct *tty;
1621 	int status;
1622 	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
1623 
1624 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1625 		dbg("%s", "Invalid port \n");
1626 		return;
1627 	}
1628 
1629 	if (mos7840_port == NULL)
1630 		return;
1631 
1632 	if (!mos7840_port->open) {
1633 		dbg("%s - port not opened", __FUNCTION__);
1634 		return;
1635 	}
1636 
1637 	dbg("%s", "Entering .......... \n");
1638 
1639 	tty = port->tty;
1640 	if (!tty) {
1641 		dbg("%s - no tty available", __FUNCTION__);
1642 		return;
1643 	}
1644 
1645 	/* if we are implementing XON/XOFF, send the start character */
1646 	if (I_IXOFF(tty)) {
1647 		unsigned char start_char = START_CHAR(tty);
1648 		status = mos7840_write(port, &start_char, 1);
1649 		if (status <= 0) {
1650 			return;
1651 		}
1652 	}
1653 
1654 	/* if we are implementing RTS/CTS, toggle that line */
1655 	if (tty->termios->c_cflag & CRTSCTS) {
1656 		mos7840_port->shadowMCR |= MCR_RTS;
1657 		status = 0;
1658 		status =
1659 		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1660 					 mos7840_port->shadowMCR);
1661 		if (status < 0) {
1662 			return;
1663 		}
1664 	}
1665 
1666 	return;
1667 }
1668 
1669 static int mos7840_tiocmget(struct usb_serial_port *port, struct file *file)
1670 {
1671 	struct moschip_port *mos7840_port;
1672 	unsigned int result;
1673 	__u16 msr;
1674 	__u16 mcr;
1675 	int status = 0;
1676 	mos7840_port = mos7840_get_port_private(port);
1677 
1678 	dbg("%s - port %d", __FUNCTION__, port->number);
1679 
1680 	if (mos7840_port == NULL)
1681 		return -ENODEV;
1682 
1683 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
1684 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1685 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1686 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1687 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1688 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1689 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1690 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1691 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1692 
1693 	dbg("%s - 0x%04X", __FUNCTION__, result);
1694 
1695 	return result;
1696 }
1697 
1698 static int mos7840_tiocmset(struct usb_serial_port *port, struct file *file,
1699 			    unsigned int set, unsigned int clear)
1700 {
1701 	struct moschip_port *mos7840_port;
1702 	unsigned int mcr;
1703 	unsigned int status;
1704 
1705 	dbg("%s - port %d", __FUNCTION__, port->number);
1706 
1707 	mos7840_port = mos7840_get_port_private(port);
1708 
1709 	if (mos7840_port == NULL)
1710 		return -ENODEV;
1711 
1712 	mcr = mos7840_port->shadowMCR;
1713 	if (clear & TIOCM_RTS)
1714 		mcr &= ~MCR_RTS;
1715 	if (clear & TIOCM_DTR)
1716 		mcr &= ~MCR_DTR;
1717 	if (clear & TIOCM_LOOP)
1718 		mcr &= ~MCR_LOOPBACK;
1719 
1720 	if (set & TIOCM_RTS)
1721 		mcr |= MCR_RTS;
1722 	if (set & TIOCM_DTR)
1723 		mcr |= MCR_DTR;
1724 	if (set & TIOCM_LOOP)
1725 		mcr |= MCR_LOOPBACK;
1726 
1727 	mos7840_port->shadowMCR = mcr;
1728 
1729 	status = 0;
1730 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1731 	if (status < 0) {
1732 		dbg("setting MODEM_CONTROL_REGISTER Failed\n");
1733 		return -1;
1734 	}
1735 
1736 	return 0;
1737 }
1738 
1739 /*****************************************************************************
1740  * mos7840_calc_baud_rate_divisor
1741  *	this function calculates the proper baud rate divisor for the specified
1742  *	baud rate.
1743  *****************************************************************************/
1744 static int mos7840_calc_baud_rate_divisor(int baudRate, int *divisor,
1745 					  __u16 * clk_sel_val)
1746 {
1747 
1748 	dbg("%s - %d", __FUNCTION__, baudRate);
1749 
1750 	if (baudRate <= 115200) {
1751 		*divisor = 115200 / baudRate;
1752 		*clk_sel_val = 0x0;
1753 	}
1754 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1755 		*divisor = 230400 / baudRate;
1756 		*clk_sel_val = 0x10;
1757 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1758 		*divisor = 403200 / baudRate;
1759 		*clk_sel_val = 0x20;
1760 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1761 		*divisor = 460800 / baudRate;
1762 		*clk_sel_val = 0x30;
1763 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1764 		*divisor = 806400 / baudRate;
1765 		*clk_sel_val = 0x40;
1766 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1767 		*divisor = 921600 / baudRate;
1768 		*clk_sel_val = 0x50;
1769 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1770 		*divisor = 1572864 / baudRate;
1771 		*clk_sel_val = 0x60;
1772 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1773 		*divisor = 3145728 / baudRate;
1774 		*clk_sel_val = 0x70;
1775 	}
1776 	return 0;
1777 
1778 #ifdef NOTMCS7840
1779 
1780 	for (i = 0; i < ARRAY_SIZE(mos7840_divisor_table); i++) {
1781 		if (mos7840_divisor_table[i].BaudRate == baudrate) {
1782 			*divisor = mos7840_divisor_table[i].Divisor;
1783 			return 0;
1784 		}
1785 	}
1786 
1787 	/* After trying for all the standard baud rates    *
1788 	 * Try calculating the divisor for this baud rate  */
1789 
1790 	if (baudrate > 75 && baudrate < 230400) {
1791 		/* get the divisor */
1792 		custom = (__u16) (230400L / baudrate);
1793 
1794 		/* Check for round off */
1795 		round1 = (__u16) (2304000L / baudrate);
1796 		round = (__u16) (round1 - (custom * 10));
1797 		if (round > 4) {
1798 			custom++;
1799 		}
1800 		*divisor = custom;
1801 
1802 		dbg(" Baud %d = %d\n", baudrate, custom);
1803 		return 0;
1804 	}
1805 
1806 	dbg("%s\n", " Baud calculation Failed...");
1807 	return -1;
1808 #endif
1809 }
1810 
1811 /*****************************************************************************
1812  * mos7840_send_cmd_write_baud_rate
1813  *	this function sends the proper command to change the baud rate of the
1814  *	specified port.
1815  *****************************************************************************/
1816 
1817 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1818 					    int baudRate)
1819 {
1820 	int divisor = 0;
1821 	int status;
1822 	__u16 Data;
1823 	unsigned char number;
1824 	__u16 clk_sel_val;
1825 	struct usb_serial_port *port;
1826 
1827 	if (mos7840_port == NULL)
1828 		return -1;
1829 
1830 	port = (struct usb_serial_port *)mos7840_port->port;
1831 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1832 		dbg("%s", "Invalid port \n");
1833 		return -1;
1834 	}
1835 
1836 	if (mos7840_serial_paranoia_check(port->serial, __FUNCTION__)) {
1837 		dbg("%s", "Invalid Serial \n");
1838 		return -1;
1839 	}
1840 
1841 	dbg("%s", "Entering .......... \n");
1842 
1843 	number = mos7840_port->port->number - mos7840_port->port->serial->minor;
1844 
1845 	dbg("%s - port = %d, baud = %d", __FUNCTION__,
1846 	    mos7840_port->port->number, baudRate);
1847 	//reset clk_uart_sel in spregOffset
1848 	if (baudRate > 115200) {
1849 #ifdef HW_flow_control
1850 		//NOTE: need to see the pther register to modify
1851 		//setting h/w flow control bit to 1;
1852 		status = 0;
1853 		Data = 0x2b;
1854 		mos7840_port->shadowMCR = Data;
1855 		status =
1856 		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1857 		if (status < 0) {
1858 			dbg("Writing spreg failed in set_serial_baud\n");
1859 			return -1;
1860 		}
1861 #endif
1862 
1863 	} else {
1864 #ifdef HW_flow_control
1865 		//setting h/w flow control bit to 0;
1866 		status = 0;
1867 		Data = 0xb;
1868 		mos7840_port->shadowMCR = Data;
1869 		status =
1870 		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1871 		if (status < 0) {
1872 			dbg("Writing spreg failed in set_serial_baud\n");
1873 			return -1;
1874 		}
1875 #endif
1876 
1877 	}
1878 
1879 	if (1)			//baudRate <= 115200)
1880 	{
1881 		clk_sel_val = 0x0;
1882 		Data = 0x0;
1883 		status = 0;
1884 		status =
1885 		    mos7840_calc_baud_rate_divisor(baudRate, &divisor,
1886 						   &clk_sel_val);
1887 		status =
1888 		    mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1889 					 &Data);
1890 		if (status < 0) {
1891 			dbg("reading spreg failed in set_serial_baud\n");
1892 			return -1;
1893 		}
1894 		Data = (Data & 0x8f) | clk_sel_val;
1895 		status = 0;
1896 		status =
1897 		    mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
1898 		if (status < 0) {
1899 			dbg("Writing spreg failed in set_serial_baud\n");
1900 			return -1;
1901 		}
1902 		/* Calculate the Divisor */
1903 
1904 		if (status) {
1905 			err("%s - bad baud rate", __FUNCTION__);
1906 			dbg("%s\n", "bad baud rate");
1907 			return status;
1908 		}
1909 		/* Enable access to divisor latch */
1910 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1911 		mos7840_port->shadowLCR = Data;
1912 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1913 
1914 		/* Write the divisor */
1915 		Data = (unsigned char)(divisor & 0xff);
1916 		dbg("set_serial_baud Value to write DLL is %x\n", Data);
1917 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1918 
1919 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1920 		dbg("set_serial_baud Value to write DLM is %x\n", Data);
1921 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1922 
1923 		/* Disable access to divisor latch */
1924 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1925 		mos7840_port->shadowLCR = Data;
1926 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1927 
1928 	}
1929 
1930 	return status;
1931 }
1932 
1933 /*****************************************************************************
1934  * mos7840_change_port_settings
1935  *	This routine is called to set the UART on the device to match
1936  *      the specified new settings.
1937  *****************************************************************************/
1938 
1939 static void mos7840_change_port_settings(struct moschip_port *mos7840_port,
1940 					 struct ktermios *old_termios)
1941 {
1942 	struct tty_struct *tty;
1943 	int baud;
1944 	unsigned cflag;
1945 	unsigned iflag;
1946 	__u8 lData;
1947 	__u8 lParity;
1948 	__u8 lStop;
1949 	int status;
1950 	__u16 Data;
1951 	struct usb_serial_port *port;
1952 	struct usb_serial *serial;
1953 
1954 	if (mos7840_port == NULL)
1955 		return;
1956 
1957 	port = (struct usb_serial_port *)mos7840_port->port;
1958 
1959 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
1960 		dbg("%s", "Invalid port \n");
1961 		return;
1962 	}
1963 
1964 	if (mos7840_serial_paranoia_check(port->serial, __FUNCTION__)) {
1965 		dbg("%s", "Invalid Serial \n");
1966 		return;
1967 	}
1968 
1969 	serial = port->serial;
1970 
1971 	dbg("%s - port %d", __FUNCTION__, mos7840_port->port->number);
1972 
1973 	if (!mos7840_port->open) {
1974 		dbg("%s - port not opened", __FUNCTION__);
1975 		return;
1976 	}
1977 
1978 	tty = mos7840_port->port->tty;
1979 
1980 	if ((!tty) || (!tty->termios)) {
1981 		dbg("%s - no tty structures", __FUNCTION__);
1982 		return;
1983 	}
1984 
1985 	dbg("%s", "Entering .......... \n");
1986 
1987 	lData = LCR_BITS_8;
1988 	lStop = LCR_STOP_1;
1989 	lParity = LCR_PAR_NONE;
1990 
1991 	cflag = tty->termios->c_cflag;
1992 	iflag = tty->termios->c_iflag;
1993 
1994 	/* Change the number of bits */
1995 	if (cflag & CSIZE) {
1996 		switch (cflag & CSIZE) {
1997 		case CS5:
1998 			lData = LCR_BITS_5;
1999 			break;
2000 
2001 		case CS6:
2002 			lData = LCR_BITS_6;
2003 			break;
2004 
2005 		case CS7:
2006 			lData = LCR_BITS_7;
2007 			break;
2008 		default:
2009 		case CS8:
2010 			lData = LCR_BITS_8;
2011 			break;
2012 		}
2013 	}
2014 	/* Change the Parity bit */
2015 	if (cflag & PARENB) {
2016 		if (cflag & PARODD) {
2017 			lParity = LCR_PAR_ODD;
2018 			dbg("%s - parity = odd", __FUNCTION__);
2019 		} else {
2020 			lParity = LCR_PAR_EVEN;
2021 			dbg("%s - parity = even", __FUNCTION__);
2022 		}
2023 
2024 	} else {
2025 		dbg("%s - parity = none", __FUNCTION__);
2026 	}
2027 
2028 	if (cflag & CMSPAR) {
2029 		lParity = lParity | 0x20;
2030 	}
2031 
2032 	/* Change the Stop bit */
2033 	if (cflag & CSTOPB) {
2034 		lStop = LCR_STOP_2;
2035 		dbg("%s - stop bits = 2", __FUNCTION__);
2036 	} else {
2037 		lStop = LCR_STOP_1;
2038 		dbg("%s - stop bits = 1", __FUNCTION__);
2039 	}
2040 
2041 	/* Update the LCR with the correct value */
2042 	mos7840_port->shadowLCR &=
2043 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
2044 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
2045 
2046 	dbg("mos7840_change_port_settings mos7840_port->shadowLCR is %x\n",
2047 	    mos7840_port->shadowLCR);
2048 	/* Disable Interrupts */
2049 	Data = 0x00;
2050 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
2051 
2052 	Data = 0x00;
2053 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
2054 
2055 	Data = 0xcf;
2056 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
2057 
2058 	/* Send the updated LCR value to the mos7840 */
2059 	Data = mos7840_port->shadowLCR;
2060 
2061 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
2062 
2063 	Data = 0x00b;
2064 	mos7840_port->shadowMCR = Data;
2065 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2066 	Data = 0x00b;
2067 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2068 
2069 	/* set up the MCR register and send it to the mos7840 */
2070 
2071 	mos7840_port->shadowMCR = MCR_MASTER_IE;
2072 	if (cflag & CBAUD) {
2073 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
2074 	}
2075 
2076 	if (cflag & CRTSCTS) {
2077 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
2078 
2079 	} else {
2080 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
2081 	}
2082 
2083 	Data = mos7840_port->shadowMCR;
2084 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2085 
2086 	/* Determine divisor based on baud rate */
2087 	baud = tty_get_baud_rate(tty);
2088 
2089 	if (!baud) {
2090 		/* pick a default, any default... */
2091 		dbg("%s\n", "Picked default baud...");
2092 		baud = 9600;
2093 	}
2094 
2095 	dbg("%s - baud rate = %d", __FUNCTION__, baud);
2096 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
2097 
2098 	/* Enable Interrupts */
2099 	Data = 0x0c;
2100 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
2101 
2102 	if (mos7840_port->read_urb->status != -EINPROGRESS) {
2103 		mos7840_port->read_urb->dev = serial->dev;
2104 
2105 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2106 
2107 		if (status) {
2108 			dbg(" usb_submit_urb(read bulk) failed, status = %d",
2109 			    status);
2110 		}
2111 	}
2112 	wake_up(&mos7840_port->delta_msr_wait);
2113 	mos7840_port->delta_msr_cond = 1;
2114 	dbg("mos7840_change_port_settings mos7840_port->shadowLCR is End %x\n",
2115 	    mos7840_port->shadowLCR);
2116 
2117 	return;
2118 }
2119 
2120 /*****************************************************************************
2121  * mos7840_set_termios
2122  *	this function is called by the tty driver when it wants to change
2123  *	the termios structure
2124  *****************************************************************************/
2125 
2126 static void mos7840_set_termios(struct usb_serial_port *port,
2127 				struct ktermios *old_termios)
2128 {
2129 	int status;
2130 	unsigned int cflag;
2131 	struct usb_serial *serial;
2132 	struct moschip_port *mos7840_port;
2133 	struct tty_struct *tty;
2134 	dbg("mos7840_set_termios: START\n");
2135 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
2136 		dbg("%s", "Invalid port \n");
2137 		return;
2138 	}
2139 
2140 	serial = port->serial;
2141 
2142 	if (mos7840_serial_paranoia_check(serial, __FUNCTION__)) {
2143 		dbg("%s", "Invalid Serial \n");
2144 		return;
2145 	}
2146 
2147 	mos7840_port = mos7840_get_port_private(port);
2148 
2149 	if (mos7840_port == NULL)
2150 		return;
2151 
2152 	tty = port->tty;
2153 
2154 	if (!port->tty || !port->tty->termios) {
2155 		dbg("%s - no tty or termios", __FUNCTION__);
2156 		return;
2157 	}
2158 
2159 	if (!mos7840_port->open) {
2160 		dbg("%s - port not opened", __FUNCTION__);
2161 		return;
2162 	}
2163 
2164 	dbg("%s\n", "setting termios - ");
2165 
2166 	cflag = tty->termios->c_cflag;
2167 
2168 	if (!cflag) {
2169 		dbg("%s %s\n", __FUNCTION__, "cflag is NULL");
2170 		return;
2171 	}
2172 
2173 	dbg("%s - clfag %08x iflag %08x", __FUNCTION__,
2174 	    tty->termios->c_cflag, RELEVANT_IFLAG(tty->termios->c_iflag));
2175 
2176 	if (old_termios) {
2177 		dbg("%s - old clfag %08x old iflag %08x", __FUNCTION__,
2178 		    old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
2179 	}
2180 
2181 	dbg("%s - port %d", __FUNCTION__, port->number);
2182 
2183 	/* change the port settings to the new ones specified */
2184 
2185 	mos7840_change_port_settings(mos7840_port, old_termios);
2186 
2187 	if (!mos7840_port->read_urb) {
2188 		dbg("%s", "URB KILLED !!!!!\n");
2189 		return;
2190 	}
2191 
2192 	if (mos7840_port->read_urb->status != -EINPROGRESS) {
2193 		mos7840_port->read_urb->dev = serial->dev;
2194 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2195 		if (status) {
2196 			dbg(" usb_submit_urb(read bulk) failed, status = %d",
2197 			    status);
2198 		}
2199 	}
2200 	return;
2201 }
2202 
2203 /*****************************************************************************
2204  * mos7840_get_lsr_info - get line status register info
2205  *
2206  * Purpose: Let user call ioctl() to get info when the UART physically
2207  * 	    is emptied.  On bus types like RS485, the transmitter must
2208  * 	    release the bus after transmitting. This must be done when
2209  * 	    the transmit shift register is empty, not be done when the
2210  * 	    transmit holding register is empty.  This functionality
2211  * 	    allows an RS485 driver to be written in user space.
2212  *****************************************************************************/
2213 
2214 static int mos7840_get_lsr_info(struct moschip_port *mos7840_port,
2215 				unsigned int __user *value)
2216 {
2217 	int count;
2218 	unsigned int result = 0;
2219 
2220 	count = mos7840_chars_in_buffer(mos7840_port->port);
2221 	if (count == 0) {
2222 		dbg("%s -- Empty", __FUNCTION__);
2223 		result = TIOCSER_TEMT;
2224 	}
2225 
2226 	if (copy_to_user(value, &result, sizeof(int)))
2227 		return -EFAULT;
2228 	return 0;
2229 }
2230 
2231 /*****************************************************************************
2232  * mos7840_set_modem_info
2233  *      function to set modem info
2234  *****************************************************************************/
2235 
2236 static int mos7840_set_modem_info(struct moschip_port *mos7840_port,
2237 				  unsigned int cmd, unsigned int __user *value)
2238 {
2239 	unsigned int mcr;
2240 	unsigned int arg;
2241 	__u16 Data;
2242 	int status;
2243 	struct usb_serial_port *port;
2244 
2245 	if (mos7840_port == NULL)
2246 		return -1;
2247 
2248 	port = (struct usb_serial_port *)mos7840_port->port;
2249 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
2250 		dbg("%s", "Invalid port \n");
2251 		return -1;
2252 	}
2253 
2254 	mcr = mos7840_port->shadowMCR;
2255 
2256 	if (copy_from_user(&arg, value, sizeof(int)))
2257 		return -EFAULT;
2258 
2259 	switch (cmd) {
2260 	case TIOCMBIS:
2261 		if (arg & TIOCM_RTS)
2262 			mcr |= MCR_RTS;
2263 		if (arg & TIOCM_DTR)
2264 			mcr |= MCR_RTS;
2265 		if (arg & TIOCM_LOOP)
2266 			mcr |= MCR_LOOPBACK;
2267 		break;
2268 
2269 	case TIOCMBIC:
2270 		if (arg & TIOCM_RTS)
2271 			mcr &= ~MCR_RTS;
2272 		if (arg & TIOCM_DTR)
2273 			mcr &= ~MCR_RTS;
2274 		if (arg & TIOCM_LOOP)
2275 			mcr &= ~MCR_LOOPBACK;
2276 		break;
2277 
2278 	case TIOCMSET:
2279 		/* turn off the RTS and DTR and LOOPBACK
2280 		 * and then only turn on what was asked to */
2281 		mcr &= ~(MCR_RTS | MCR_DTR | MCR_LOOPBACK);
2282 		mcr |= ((arg & TIOCM_RTS) ? MCR_RTS : 0);
2283 		mcr |= ((arg & TIOCM_DTR) ? MCR_DTR : 0);
2284 		mcr |= ((arg & TIOCM_LOOP) ? MCR_LOOPBACK : 0);
2285 		break;
2286 	}
2287 
2288 	mos7840_port->shadowMCR = mcr;
2289 
2290 	Data = mos7840_port->shadowMCR;
2291 	status = 0;
2292 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2293 	if (status < 0) {
2294 		dbg("setting MODEM_CONTROL_REGISTER Failed\n");
2295 		return -1;
2296 	}
2297 
2298 	return 0;
2299 }
2300 
2301 /*****************************************************************************
2302  * mos7840_get_modem_info
2303  *      function to get modem info
2304  *****************************************************************************/
2305 
2306 static int mos7840_get_modem_info(struct moschip_port *mos7840_port,
2307 				  unsigned int __user *value)
2308 {
2309 	unsigned int result = 0;
2310 	__u16 msr;
2311 	unsigned int mcr = mos7840_port->shadowMCR;
2312 	int status = 0;
2313 	status =
2314 	    mos7840_get_uart_reg(mos7840_port->port, MODEM_STATUS_REGISTER,
2315 				 &msr);
2316 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)	/* 0x002 */
2317 	    |((mcr & MCR_RTS) ? TIOCM_RTS : 0)	/* 0x004 */
2318 	    |((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)	/* 0x020 */
2319 	    |((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)	/* 0x040 */
2320 	    |((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)	/* 0x080 */
2321 	    |((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);	/* 0x100 */
2322 
2323 	dbg("%s -- %x", __FUNCTION__, result);
2324 
2325 	if (copy_to_user(value, &result, sizeof(int)))
2326 		return -EFAULT;
2327 	return 0;
2328 }
2329 
2330 /*****************************************************************************
2331  * mos7840_get_serial_info
2332  *      function to get information about serial port
2333  *****************************************************************************/
2334 
2335 static int mos7840_get_serial_info(struct moschip_port *mos7840_port,
2336 				   struct serial_struct __user *retinfo)
2337 {
2338 	struct serial_struct tmp;
2339 
2340 	if (mos7840_port == NULL)
2341 		return -1;
2342 
2343 	if (!retinfo)
2344 		return -EFAULT;
2345 
2346 	memset(&tmp, 0, sizeof(tmp));
2347 
2348 	tmp.type = PORT_16550A;
2349 	tmp.line = mos7840_port->port->serial->minor;
2350 	tmp.port = mos7840_port->port->number;
2351 	tmp.irq = 0;
2352 	tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
2353 	tmp.xmit_fifo_size = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
2354 	tmp.baud_base = 9600;
2355 	tmp.close_delay = 5 * HZ;
2356 	tmp.closing_wait = 30 * HZ;
2357 
2358 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
2359 		return -EFAULT;
2360 	return 0;
2361 }
2362 
2363 /*****************************************************************************
2364  * SerialIoctl
2365  *	this function handles any ioctl calls to the driver
2366  *****************************************************************************/
2367 
2368 static int mos7840_ioctl(struct usb_serial_port *port, struct file *file,
2369 			 unsigned int cmd, unsigned long arg)
2370 {
2371 	void __user *argp = (void __user *)arg;
2372 	struct moschip_port *mos7840_port;
2373 	struct tty_struct *tty;
2374 
2375 	struct async_icount cnow;
2376 	struct async_icount cprev;
2377 	struct serial_icounter_struct icount;
2378 	int mosret = 0;
2379 
2380 	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
2381 		dbg("%s", "Invalid port \n");
2382 		return -1;
2383 	}
2384 
2385 	mos7840_port = mos7840_get_port_private(port);
2386 
2387 	if (mos7840_port == NULL)
2388 		return -1;
2389 
2390 	tty = mos7840_port->port->tty;
2391 
2392 	dbg("%s - port %d, cmd = 0x%x", __FUNCTION__, port->number, cmd);
2393 
2394 	switch (cmd) {
2395 		/* return number of bytes available */
2396 
2397 	case TIOCSERGETLSR:
2398 		dbg("%s (%d) TIOCSERGETLSR", __FUNCTION__, port->number);
2399 		return mos7840_get_lsr_info(mos7840_port, argp);
2400 		return 0;
2401 
2402 	case TIOCMBIS:
2403 	case TIOCMBIC:
2404 	case TIOCMSET:
2405 		dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET", __FUNCTION__,
2406 		    port->number);
2407 		mosret =
2408 		    mos7840_set_modem_info(mos7840_port, cmd, argp);
2409 		return mosret;
2410 
2411 	case TIOCMGET:
2412 		dbg("%s (%d) TIOCMGET", __FUNCTION__, port->number);
2413 		return mos7840_get_modem_info(mos7840_port, argp);
2414 
2415 	case TIOCGSERIAL:
2416 		dbg("%s (%d) TIOCGSERIAL", __FUNCTION__, port->number);
2417 		return mos7840_get_serial_info(mos7840_port, argp);
2418 
2419 	case TIOCSSERIAL:
2420 		dbg("%s (%d) TIOCSSERIAL", __FUNCTION__, port->number);
2421 		break;
2422 
2423 	case TIOCMIWAIT:
2424 		dbg("%s (%d) TIOCMIWAIT", __FUNCTION__, port->number);
2425 		cprev = mos7840_port->icount;
2426 		while (1) {
2427 			//interruptible_sleep_on(&mos7840_port->delta_msr_wait);
2428 			mos7840_port->delta_msr_cond = 0;
2429 			wait_event_interruptible(mos7840_port->delta_msr_wait,
2430 						 (mos7840_port->
2431 						  delta_msr_cond == 1));
2432 
2433 			/* see if a signal did it */
2434 			if (signal_pending(current))
2435 				return -ERESTARTSYS;
2436 			cnow = mos7840_port->icount;
2437 			smp_rmb();
2438 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2439 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
2440 				return -EIO;	/* no change => error */
2441 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
2442 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
2443 			    ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
2444 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
2445 				return 0;
2446 			}
2447 			cprev = cnow;
2448 		}
2449 		/* NOTREACHED */
2450 		break;
2451 
2452 	case TIOCGICOUNT:
2453 		cnow = mos7840_port->icount;
2454 		smp_rmb();
2455 		icount.cts = cnow.cts;
2456 		icount.dsr = cnow.dsr;
2457 		icount.rng = cnow.rng;
2458 		icount.dcd = cnow.dcd;
2459 		icount.rx = cnow.rx;
2460 		icount.tx = cnow.tx;
2461 		icount.frame = cnow.frame;
2462 		icount.overrun = cnow.overrun;
2463 		icount.parity = cnow.parity;
2464 		icount.brk = cnow.brk;
2465 		icount.buf_overrun = cnow.buf_overrun;
2466 
2467 		dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __FUNCTION__,
2468 		    port->number, icount.rx, icount.tx);
2469 		if (copy_to_user(argp, &icount, sizeof(icount)))
2470 			return -EFAULT;
2471 		return 0;
2472 
2473 	case TIOCEXBAUD:
2474 		return 0;
2475 	default:
2476 		break;
2477 	}
2478 
2479 	return -ENOIOCTLCMD;
2480 }
2481 
2482 static int mos7840_calc_num_ports(struct usb_serial *serial)
2483 {
2484 	int mos7840_num_ports = 0;
2485 
2486 	dbg("numberofendpoints: %d \n",
2487 	    (int)serial->interface->cur_altsetting->desc.bNumEndpoints);
2488 	dbg("numberofendpoints: %d \n",
2489 	    (int)serial->interface->altsetting->desc.bNumEndpoints);
2490 	if (serial->interface->cur_altsetting->desc.bNumEndpoints == 5) {
2491 		mos7840_num_ports = serial->num_ports = 2;
2492 	} else if (serial->interface->cur_altsetting->desc.bNumEndpoints == 9) {
2493 		serial->num_bulk_in = 4;
2494 		serial->num_bulk_out = 4;
2495 		mos7840_num_ports = serial->num_ports = 4;
2496 	}
2497 
2498 	return mos7840_num_ports;
2499 }
2500 
2501 /****************************************************************************
2502  * mos7840_startup
2503  ****************************************************************************/
2504 
2505 static int mos7840_startup(struct usb_serial *serial)
2506 {
2507 	struct moschip_port *mos7840_port;
2508 	struct usb_device *dev;
2509 	int i, status;
2510 
2511 	__u16 Data;
2512 	dbg("%s \n", " mos7840_startup :entering..........");
2513 
2514 	if (!serial) {
2515 		dbg("%s\n", "Invalid Handler");
2516 		return -1;
2517 	}
2518 
2519 	dev = serial->dev;
2520 
2521 	dbg("%s\n", "Entering...");
2522 
2523 	/* we set up the pointers to the endpoints in the mos7840_open *
2524 	 * function, as the structures aren't created yet.             */
2525 
2526 	/* set up port private structures */
2527 	for (i = 0; i < serial->num_ports; ++i) {
2528 		mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2529 		if (mos7840_port == NULL) {
2530 			err("%s - Out of memory", __FUNCTION__);
2531 			status = -ENOMEM;
2532 			i--; /* don't follow NULL pointer cleaning up */
2533 			goto error;
2534 		}
2535 
2536 		/* Initialize all port interrupt end point to port 0 int endpoint *
2537 		 * Our device has only one interrupt end point comman to all port */
2538 
2539 		mos7840_port->port = serial->port[i];
2540 		mos7840_set_port_private(serial->port[i], mos7840_port);
2541 		spin_lock_init(&mos7840_port->pool_lock);
2542 
2543 		mos7840_port->port_num = ((serial->port[i]->number -
2544 					   (serial->port[i]->serial->minor)) +
2545 					  1);
2546 
2547 		if (mos7840_port->port_num == 1) {
2548 			mos7840_port->SpRegOffset = 0x0;
2549 			mos7840_port->ControlRegOffset = 0x1;
2550 			mos7840_port->DcrRegOffset = 0x4;
2551 		} else if ((mos7840_port->port_num == 2)
2552 			   && (serial->num_ports == 4)) {
2553 			mos7840_port->SpRegOffset = 0x8;
2554 			mos7840_port->ControlRegOffset = 0x9;
2555 			mos7840_port->DcrRegOffset = 0x16;
2556 		} else if ((mos7840_port->port_num == 2)
2557 			   && (serial->num_ports == 2)) {
2558 			mos7840_port->SpRegOffset = 0xa;
2559 			mos7840_port->ControlRegOffset = 0xb;
2560 			mos7840_port->DcrRegOffset = 0x19;
2561 		} else if ((mos7840_port->port_num == 3)
2562 			   && (serial->num_ports == 4)) {
2563 			mos7840_port->SpRegOffset = 0xa;
2564 			mos7840_port->ControlRegOffset = 0xb;
2565 			mos7840_port->DcrRegOffset = 0x19;
2566 		} else if ((mos7840_port->port_num == 4)
2567 			   && (serial->num_ports == 4)) {
2568 			mos7840_port->SpRegOffset = 0xc;
2569 			mos7840_port->ControlRegOffset = 0xd;
2570 			mos7840_port->DcrRegOffset = 0x1c;
2571 		}
2572 		mos7840_dump_serial_port(mos7840_port);
2573 
2574 		mos7840_set_port_private(serial->port[i], mos7840_port);
2575 
2576 		//enable rx_disable bit in control register
2577 
2578 		status =
2579 		    mos7840_get_reg_sync(serial->port[i],
2580 					 mos7840_port->ControlRegOffset, &Data);
2581 		if (status < 0) {
2582 			dbg("Reading ControlReg failed status-0x%x\n", status);
2583 			break;
2584 		} else
2585 			dbg("ControlReg Reading success val is %x, status%d\n",
2586 			    Data, status);
2587 		Data |= 0x08;	//setting driver done bit
2588 		Data |= 0x04;	//sp1_bit to have cts change reflect in modem status reg
2589 
2590 		//Data |= 0x20; //rx_disable bit
2591 		status = 0;
2592 		status =
2593 		    mos7840_set_reg_sync(serial->port[i],
2594 					 mos7840_port->ControlRegOffset, Data);
2595 		if (status < 0) {
2596 			dbg("Writing ControlReg failed(rx_disable) status-0x%x\n", status);
2597 			break;
2598 		} else
2599 			dbg("ControlReg Writing success(rx_disable) status%d\n",
2600 			    status);
2601 
2602 		//Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2 and 0x24 in DCR3
2603 		Data = 0x01;
2604 		status = 0;
2605 		status =
2606 		    mos7840_set_reg_sync(serial->port[i],
2607 					 (__u16) (mos7840_port->DcrRegOffset +
2608 						  0), Data);
2609 		if (status < 0) {
2610 			dbg("Writing DCR0 failed status-0x%x\n", status);
2611 			break;
2612 		} else
2613 			dbg("DCR0 Writing success status%d\n", status);
2614 
2615 		Data = 0x05;
2616 		status = 0;
2617 		status =
2618 		    mos7840_set_reg_sync(serial->port[i],
2619 					 (__u16) (mos7840_port->DcrRegOffset +
2620 						  1), Data);
2621 		if (status < 0) {
2622 			dbg("Writing DCR1 failed status-0x%x\n", status);
2623 			break;
2624 		} else
2625 			dbg("DCR1 Writing success status%d\n", status);
2626 
2627 		Data = 0x24;
2628 		status = 0;
2629 		status =
2630 		    mos7840_set_reg_sync(serial->port[i],
2631 					 (__u16) (mos7840_port->DcrRegOffset +
2632 						  2), Data);
2633 		if (status < 0) {
2634 			dbg("Writing DCR2 failed status-0x%x\n", status);
2635 			break;
2636 		} else
2637 			dbg("DCR2 Writing success status%d\n", status);
2638 
2639 		// write values in clkstart0x0 and clkmulti 0x20
2640 		Data = 0x0;
2641 		status = 0;
2642 		status =
2643 		    mos7840_set_reg_sync(serial->port[i],
2644 					 CLK_START_VALUE_REGISTER, Data);
2645 		if (status < 0) {
2646 			dbg("Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
2647 			break;
2648 		} else
2649 			dbg("CLK_START_VALUE_REGISTER Writing success status%d\n", status);
2650 
2651 		Data = 0x20;
2652 		status =
2653 		    mos7840_set_reg_sync(serial->port[i], CLK_MULTI_REGISTER,
2654 					 Data);
2655 		if (status < 0) {
2656 			dbg("Writing CLK_MULTI_REGISTER failed status-0x%x\n",
2657 			    status);
2658 			goto error;
2659 		} else
2660 			dbg("CLK_MULTI_REGISTER Writing success status%d\n",
2661 			    status);
2662 
2663 		//write value 0x0 to scratchpad register
2664 		Data = 0x00;
2665 		status =
2666 		    mos7840_set_uart_reg(serial->port[i], SCRATCH_PAD_REGISTER,
2667 					 Data);
2668 		if (status < 0) {
2669 			dbg("Writing SCRATCH_PAD_REGISTER failed status-0x%x\n",
2670 			    status);
2671 			break;
2672 		} else
2673 			dbg("SCRATCH_PAD_REGISTER Writing success status%d\n",
2674 			    status);
2675 
2676 		//Zero Length flag register
2677 		if ((mos7840_port->port_num != 1)
2678 		    && (serial->num_ports == 2)) {
2679 
2680 			Data = 0xff;
2681 			status = 0;
2682 			status = mos7840_set_reg_sync(serial->port[i],
2683 						      (__u16) (ZLP_REG1 +
2684 							       ((__u16)
2685 								mos7840_port->
2686 								port_num)),
2687 						      Data);
2688 			dbg("ZLIP offset%x\n",
2689 			    (__u16) (ZLP_REG1 +
2690 				     ((__u16) mos7840_port->port_num)));
2691 			if (status < 0) {
2692 				dbg("Writing ZLP_REG%d failed status-0x%x\n",
2693 				    i + 2, status);
2694 				break;
2695 			} else
2696 				dbg("ZLP_REG%d Writing success status%d\n",
2697 				    i + 2, status);
2698 		} else {
2699 			Data = 0xff;
2700 			status = 0;
2701 			status = mos7840_set_reg_sync(serial->port[i],
2702 						      (__u16) (ZLP_REG1 +
2703 							       ((__u16)
2704 								mos7840_port->
2705 								port_num) -
2706 							       0x1), Data);
2707 			dbg("ZLIP offset%x\n",
2708 			    (__u16) (ZLP_REG1 +
2709 				     ((__u16) mos7840_port->port_num) - 0x1));
2710 			if (status < 0) {
2711 				dbg("Writing ZLP_REG%d failed status-0x%x\n",
2712 				    i + 1, status);
2713 				break;
2714 			} else
2715 				dbg("ZLP_REG%d Writing success status%d\n",
2716 				    i + 1, status);
2717 
2718 		}
2719 		mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
2720 		mos7840_port->ctrl_buf = kmalloc(16, GFP_KERNEL);
2721 		mos7840_port->dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
2722 		if (!mos7840_port->control_urb || !mos7840_port->ctrl_buf || !mos7840_port->dr) {
2723 			status = -ENOMEM;
2724 			goto error;
2725 		}
2726 	}
2727 
2728 	//Zero Length flag enable
2729 	Data = 0x0f;
2730 	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
2731 	if (status < 0) {
2732 		dbg("Writing ZLP_REG5 failed status-0x%x\n", status);
2733 		return -1;
2734 	} else
2735 		dbg("ZLP_REG5 Writing success status%d\n", status);
2736 
2737 	/* setting configuration feature to one */
2738 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2739 			(__u8) 0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5 * HZ);
2740 	return 0;
2741 error:
2742 	for (/* nothing */; i >= 0; i--) {
2743 		mos7840_port = mos7840_get_port_private(serial->port[i]);
2744 
2745 		kfree(mos7840_port->dr);
2746 		kfree(mos7840_port->ctrl_buf);
2747 		usb_free_urb(mos7840_port->control_urb);
2748 		kfree(mos7840_port);
2749 		serial->port[i] = NULL;
2750 	}
2751 	return status;
2752 }
2753 
2754 /****************************************************************************
2755  * mos7840_shutdown
2756  *	This function is called whenever the device is removed from the usb bus.
2757  ****************************************************************************/
2758 
2759 static void mos7840_shutdown(struct usb_serial *serial)
2760 {
2761 	int i;
2762 	unsigned long flags;
2763 	struct moschip_port *mos7840_port;
2764 	dbg("%s \n", " shutdown :entering..........");
2765 
2766 	if (!serial) {
2767 		dbg("%s", "Invalid Handler \n");
2768 		return;
2769 	}
2770 
2771 	/*      check for the ports to be closed,close the ports and disconnect         */
2772 
2773 	/* free private structure allocated for serial port  *
2774 	 * stop reads and writes on all ports                */
2775 
2776 	for (i = 0; i < serial->num_ports; ++i) {
2777 		mos7840_port = mos7840_get_port_private(serial->port[i]);
2778 		spin_lock_irqsave(&mos7840_port->pool_lock, flags);
2779 		mos7840_port->zombie = 1;
2780 		spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
2781 		usb_kill_urb(mos7840_port->control_urb);
2782 		kfree(mos7840_port->ctrl_buf);
2783 		kfree(mos7840_port->dr);
2784 		kfree(mos7840_port);
2785 		mos7840_set_port_private(serial->port[i], NULL);
2786 	}
2787 
2788 	dbg("%s\n", "Thank u :: ");
2789 
2790 }
2791 
2792 static struct usb_driver io_driver = {
2793 	.name = "mos7840",
2794 	.probe = usb_serial_probe,
2795 	.disconnect = usb_serial_disconnect,
2796 	.id_table = moschip_id_table_combined,
2797 	.no_dynamic_id = 1,
2798 };
2799 
2800 static struct usb_serial_driver moschip7840_4port_device = {
2801 	.driver = {
2802 		   .owner = THIS_MODULE,
2803 		   .name = "mos7840",
2804 		   },
2805 	.description = DRIVER_DESC,
2806 	.usb_driver = &io_driver,
2807 	.id_table = moschip_port_id_table,
2808 	.num_interrupt_in = 1,	//NUM_DONT_CARE,//1,
2809 #ifdef check
2810 	.num_bulk_in = 4,
2811 	.num_bulk_out = 4,
2812 	.num_ports = 4,
2813 #endif
2814 	.open = mos7840_open,
2815 	.close = mos7840_close,
2816 	.write = mos7840_write,
2817 	.write_room = mos7840_write_room,
2818 	.chars_in_buffer = mos7840_chars_in_buffer,
2819 	.throttle = mos7840_throttle,
2820 	.unthrottle = mos7840_unthrottle,
2821 	.calc_num_ports = mos7840_calc_num_ports,
2822 #ifdef MCSSerialProbe
2823 	.probe = mos7840_serial_probe,
2824 #endif
2825 	.ioctl = mos7840_ioctl,
2826 	.set_termios = mos7840_set_termios,
2827 	.break_ctl = mos7840_break,
2828 	.tiocmget = mos7840_tiocmget,
2829 	.tiocmset = mos7840_tiocmset,
2830 	.attach = mos7840_startup,
2831 	.shutdown = mos7840_shutdown,
2832 	.read_bulk_callback = mos7840_bulk_in_callback,
2833 	.read_int_callback = mos7840_interrupt_callback,
2834 };
2835 
2836 /****************************************************************************
2837  * moschip7840_init
2838  *	This is called by the module subsystem, or on startup to initialize us
2839  ****************************************************************************/
2840 static int __init moschip7840_init(void)
2841 {
2842 	int retval;
2843 
2844 	dbg("%s \n", " mos7840_init :entering..........");
2845 
2846 	/* Register with the usb serial */
2847 	retval = usb_serial_register(&moschip7840_4port_device);
2848 
2849 	if (retval)
2850 		goto failed_port_device_register;
2851 
2852 	dbg("%s\n", "Entring...");
2853 	info(DRIVER_DESC " " DRIVER_VERSION);
2854 
2855 	/* Register with the usb */
2856 	retval = usb_register(&io_driver);
2857 
2858 	if (retval)
2859 		goto failed_usb_register;
2860 
2861 	if (retval == 0) {
2862 		dbg("%s\n", "Leaving...");
2863 		return 0;
2864 	}
2865 
2866       failed_usb_register:
2867 	usb_serial_deregister(&moschip7840_4port_device);
2868 
2869       failed_port_device_register:
2870 
2871 	return retval;
2872 }
2873 
2874 /****************************************************************************
2875  * moschip7840_exit
2876  *	Called when the driver is about to be unloaded.
2877  ****************************************************************************/
2878 static void __exit moschip7840_exit(void)
2879 {
2880 
2881 	dbg("%s \n", " mos7840_exit :entering..........");
2882 
2883 	usb_deregister(&io_driver);
2884 
2885 	usb_serial_deregister(&moschip7840_4port_device);
2886 
2887 	dbg("%s\n", "Entring...");
2888 }
2889 
2890 module_init(moschip7840_init);
2891 module_exit(moschip7840_exit);
2892 
2893 /* Module information */
2894 MODULE_DESCRIPTION(DRIVER_DESC);
2895 MODULE_LICENSE("GPL");
2896 
2897 module_param(debug, bool, S_IRUGO | S_IWUSR);
2898 MODULE_PARM_DESC(debug, "Debug enabled or not");
2899