xref: /openbmc/linux/drivers/usb/serial/mos7840.c (revision 9ac8d3fb)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License as published by
4  * the Free Software Foundation; either version 2 of the License, or
5  * (at your option) any later version.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program; if not, write to the Free Software
14  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
15  *
16  * Clean ups from Moschip version and a few ioctl implementations by:
17  *	Paul B Schroeder <pschroeder "at" uplogix "dot" com>
18  *
19  * Originally based on drivers/usb/serial/io_edgeport.c which is:
20  *      Copyright (C) 2000 Inside Out Networks, All rights reserved.
21  *      Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
22  *
23  */
24 
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/tty.h>
30 #include <linux/tty_driver.h>
31 #include <linux/tty_flip.h>
32 #include <linux/module.h>
33 #include <linux/serial.h>
34 #include <linux/usb.h>
35 #include <linux/usb/serial.h>
36 #include <linux/uaccess.h>
37 
38 /*
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 /* The native mos7840/7820 component */
114 #define USB_VENDOR_ID_MOSCHIP           0x9710
115 #define MOSCHIP_DEVICE_ID_7840          0x7840
116 #define MOSCHIP_DEVICE_ID_7820          0x7820
117 /* The native component can have its vendor/device id's overridden
118  * in vendor-specific implementations.  Such devices can be handled
119  * by making a change here, in moschip_port_id_table, and in
120  * moschip_id_table_combined
121  */
122 #define USB_VENDOR_ID_BANDB             0x0856
123 #define BANDB_DEVICE_ID_USOPTL4_4       0xAC44
124 #define BANDB_DEVICE_ID_USOPTL4_2       0xAC42
125 
126 /* Interrupt Routine Defines    */
127 
128 #define SERIAL_IIR_RLS      0x06
129 #define SERIAL_IIR_MS       0x00
130 
131 /*
132  *  Emulation of the bit mask on the LINE STATUS REGISTER.
133  */
134 #define SERIAL_LSR_DR       0x0001
135 #define SERIAL_LSR_OE       0x0002
136 #define SERIAL_LSR_PE       0x0004
137 #define SERIAL_LSR_FE       0x0008
138 #define SERIAL_LSR_BI       0x0010
139 
140 #define MOS_MSR_DELTA_CTS   0x10
141 #define MOS_MSR_DELTA_DSR   0x20
142 #define MOS_MSR_DELTA_RI    0x40
143 #define MOS_MSR_DELTA_CD    0x80
144 
145 /* Serial Port register Address */
146 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
147 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
148 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
149 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
150 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
151 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
152 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
153 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
154 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
155 
156 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
157 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
158 
159 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
160 
161 /*
162  * URB POOL related defines
163  */
164 #define NUM_URBS                        16	/* URB Count */
165 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
166 
167 
168 static struct usb_device_id moschip_port_id_table[] = {
169 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
170 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
171 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4)},
172 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2)},
173 	{}			/* terminating entry */
174 };
175 
176 static __devinitdata struct usb_device_id moschip_id_table_combined[] = {
177 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
178 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
179 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4)},
180 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2)},
181 	{}			/* terminating entry */
182 };
183 
184 MODULE_DEVICE_TABLE(usb, moschip_id_table_combined);
185 
186 /* This structure holds all of the local port information */
187 
188 struct moschip_port {
189 	int port_num;		/*Actual port number in the device(1,2,etc) */
190 	struct urb *write_urb;	/* write URB for this port */
191 	struct urb *read_urb;	/* read URB for this port */
192 	struct urb *int_urb;
193 	__u8 shadowLCR;		/* last LCR value received */
194 	__u8 shadowMCR;		/* last MCR value received */
195 	char open;
196 	char open_ports;
197 	char zombie;
198 	wait_queue_head_t wait_chase;	/* for handling sleeping while waiting for chase to finish */
199 	wait_queue_head_t delta_msr_wait;	/* for handling sleeping while waiting for msr change to happen */
200 	int delta_msr_cond;
201 	struct async_icount icount;
202 	struct usb_serial_port *port;	/* loop back to the owner of this object */
203 
204 	/* Offsets */
205 	__u8 SpRegOffset;
206 	__u8 ControlRegOffset;
207 	__u8 DcrRegOffset;
208 	/* for processing control URBS in interrupt context */
209 	struct urb *control_urb;
210 	struct usb_ctrlrequest *dr;
211 	char *ctrl_buf;
212 	int MsrLsr;
213 
214 	spinlock_t pool_lock;
215 	struct urb *write_urb_pool[NUM_URBS];
216 	char busy[NUM_URBS];
217 };
218 
219 
220 static int debug;
221 
222 /*
223  * mos7840_set_reg_sync
224  * 	To set the Control register by calling usb_fill_control_urb function
225  *	by passing usb_sndctrlpipe function as parameter.
226  */
227 
228 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
229 				__u16 val)
230 {
231 	struct usb_device *dev = port->serial->dev;
232 	val = val & 0x00ff;
233 	dbg("mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
234 
235 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
236 			       MCS_WR_RTYPE, val, reg, NULL, 0,
237 			       MOS_WDR_TIMEOUT);
238 }
239 
240 /*
241  * mos7840_get_reg_sync
242  * 	To set the Uart register by calling usb_fill_control_urb function by
243  *	passing usb_rcvctrlpipe function as parameter.
244  */
245 
246 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
247 				__u16 *val)
248 {
249 	struct usb_device *dev = port->serial->dev;
250 	int ret = 0;
251 
252 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
253 			      MCS_RD_RTYPE, 0, reg, val, VENDOR_READ_LENGTH,
254 			      MOS_WDR_TIMEOUT);
255 	dbg("mos7840_get_reg_sync offset is %x, return val %x\n", reg, *val);
256 	*val = (*val) & 0x00ff;
257 	return ret;
258 }
259 
260 /*
261  * mos7840_set_uart_reg
262  *	To set the Uart register by calling usb_fill_control_urb function by
263  *	passing usb_sndctrlpipe function as parameter.
264  */
265 
266 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
267 				__u16 val)
268 {
269 
270 	struct usb_device *dev = port->serial->dev;
271 	val = val & 0x00ff;
272 	/* For the UART control registers, the application number need
273 	   to be Or'ed */
274 	if (port->serial->num_ports == 4) {
275 		val |= (((__u16) port->number -
276 				(__u16) (port->serial->minor)) + 1) << 8;
277 		dbg("mos7840_set_uart_reg application number is %x\n", val);
278 	} else {
279 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
280 			val |= (((__u16) port->number -
281 			      (__u16) (port->serial->minor)) + 1) << 8;
282 			dbg("mos7840_set_uart_reg application number is %x\n",
283 			    val);
284 		} else {
285 			val |=
286 			    (((__u16) port->number -
287 			      (__u16) (port->serial->minor)) + 2) << 8;
288 			dbg("mos7840_set_uart_reg application number is %x\n",
289 			    val);
290 		}
291 	}
292 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
293 			       MCS_WR_RTYPE, val, reg, NULL, 0,
294 			       MOS_WDR_TIMEOUT);
295 
296 }
297 
298 /*
299  * mos7840_get_uart_reg
300  *	To set the Control register by calling usb_fill_control_urb function
301  *	by passing usb_rcvctrlpipe function as parameter.
302  */
303 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
304 				__u16 *val)
305 {
306 	struct usb_device *dev = port->serial->dev;
307 	int ret = 0;
308 	__u16 Wval;
309 
310 	/* dbg("application number is %4x \n",
311 	    (((__u16)port->number - (__u16)(port->serial->minor))+1)<<8); */
312 	/* Wval  is same as application number */
313 	if (port->serial->num_ports == 4) {
314 		Wval =
315 		    (((__u16) port->number - (__u16) (port->serial->minor)) +
316 		     1) << 8;
317 		dbg("mos7840_get_uart_reg application number is %x\n", Wval);
318 	} else {
319 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
320 			Wval = (((__u16) port->number -
321 			      (__u16) (port->serial->minor)) + 1) << 8;
322 			dbg("mos7840_get_uart_reg application number is %x\n",
323 			    Wval);
324 		} else {
325 			Wval = (((__u16) port->number -
326 			      (__u16) (port->serial->minor)) + 2) << 8;
327 			dbg("mos7840_get_uart_reg application number is %x\n",
328 			    Wval);
329 		}
330 	}
331 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
332 			      MCS_RD_RTYPE, Wval, reg, val, VENDOR_READ_LENGTH,
333 			      MOS_WDR_TIMEOUT);
334 	*val = (*val) & 0x00ff;
335 	return ret;
336 }
337 
338 static void mos7840_dump_serial_port(struct moschip_port *mos7840_port)
339 {
340 
341 	dbg("***************************************\n");
342 	dbg("SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
343 	dbg("ControlRegOffset is %2x \n", mos7840_port->ControlRegOffset);
344 	dbg("DCRRegOffset is %2x \n", mos7840_port->DcrRegOffset);
345 	dbg("***************************************\n");
346 
347 }
348 
349 /************************************************************************/
350 /************************************************************************/
351 /*             I N T E R F A C E   F U N C T I O N S			*/
352 /*             I N T E R F A C E   F U N C T I O N S			*/
353 /************************************************************************/
354 /************************************************************************/
355 
356 static inline void mos7840_set_port_private(struct usb_serial_port *port,
357 					    struct moschip_port *data)
358 {
359 	usb_set_serial_port_data(port, (void *)data);
360 }
361 
362 static inline struct moschip_port *mos7840_get_port_private(struct
363 							    usb_serial_port
364 							    *port)
365 {
366 	return (struct moschip_port *)usb_get_serial_port_data(port);
367 }
368 
369 static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
370 {
371 	struct moschip_port *mos7840_port;
372 	struct async_icount *icount;
373 	mos7840_port = port;
374 	icount = &mos7840_port->icount;
375 	if (new_msr &
376 	    (MOS_MSR_DELTA_CTS | MOS_MSR_DELTA_DSR | MOS_MSR_DELTA_RI |
377 	     MOS_MSR_DELTA_CD)) {
378 		icount = &mos7840_port->icount;
379 
380 		/* update input line counters */
381 		if (new_msr & MOS_MSR_DELTA_CTS) {
382 			icount->cts++;
383 			smp_wmb();
384 		}
385 		if (new_msr & MOS_MSR_DELTA_DSR) {
386 			icount->dsr++;
387 			smp_wmb();
388 		}
389 		if (new_msr & MOS_MSR_DELTA_CD) {
390 			icount->dcd++;
391 			smp_wmb();
392 		}
393 		if (new_msr & MOS_MSR_DELTA_RI) {
394 			icount->rng++;
395 			smp_wmb();
396 		}
397 	}
398 }
399 
400 static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)
401 {
402 	struct async_icount *icount;
403 
404 	dbg("%s - %02x", __func__, new_lsr);
405 
406 	if (new_lsr & SERIAL_LSR_BI) {
407 		/*
408 		 * Parity and Framing errors only count if they
409 		 * occur exclusive of a break being
410 		 * received.
411 		 */
412 		new_lsr &= (__u8) (SERIAL_LSR_OE | SERIAL_LSR_BI);
413 	}
414 
415 	/* update input line counters */
416 	icount = &port->icount;
417 	if (new_lsr & SERIAL_LSR_BI) {
418 		icount->brk++;
419 		smp_wmb();
420 	}
421 	if (new_lsr & SERIAL_LSR_OE) {
422 		icount->overrun++;
423 		smp_wmb();
424 	}
425 	if (new_lsr & SERIAL_LSR_PE) {
426 		icount->parity++;
427 		smp_wmb();
428 	}
429 	if (new_lsr & SERIAL_LSR_FE) {
430 		icount->frame++;
431 		smp_wmb();
432 	}
433 }
434 
435 /************************************************************************/
436 /************************************************************************/
437 /*            U S B  C A L L B A C K   F U N C T I O N S                */
438 /*            U S B  C A L L B A C K   F U N C T I O N S                */
439 /************************************************************************/
440 /************************************************************************/
441 
442 static void mos7840_control_callback(struct urb *urb)
443 {
444 	unsigned char *data;
445 	struct moschip_port *mos7840_port;
446 	__u8 regval = 0x0;
447 	int result = 0;
448 	int status = urb->status;
449 
450 	mos7840_port = urb->context;
451 
452 	switch (status) {
453 	case 0:
454 		/* success */
455 		break;
456 	case -ECONNRESET:
457 	case -ENOENT:
458 	case -ESHUTDOWN:
459 		/* this urb is terminated, clean up */
460 		dbg("%s - urb shutting down with status: %d", __func__,
461 		    status);
462 		return;
463 	default:
464 		dbg("%s - nonzero urb status received: %d", __func__,
465 		    status);
466 		goto exit;
467 	}
468 
469 	dbg("%s urb buffer size is %d\n", __func__, urb->actual_length);
470 	dbg("%s mos7840_port->MsrLsr is %d port %d\n", __func__,
471 	    mos7840_port->MsrLsr, mos7840_port->port_num);
472 	data = urb->transfer_buffer;
473 	regval = (__u8) data[0];
474 	dbg("%s data is %x\n", __func__, regval);
475 	if (mos7840_port->MsrLsr == 0)
476 		mos7840_handle_new_msr(mos7840_port, regval);
477 	else if (mos7840_port->MsrLsr == 1)
478 		mos7840_handle_new_lsr(mos7840_port, regval);
479 
480 exit:
481 	spin_lock(&mos7840_port->pool_lock);
482 	if (!mos7840_port->zombie)
483 		result = usb_submit_urb(mos7840_port->int_urb, GFP_ATOMIC);
484 	spin_unlock(&mos7840_port->pool_lock);
485 	if (result) {
486 		dev_err(&urb->dev->dev,
487 			"%s - Error %d submitting interrupt urb\n",
488 			__func__, result);
489 	}
490 }
491 
492 static int mos7840_get_reg(struct moschip_port *mcs, __u16 Wval, __u16 reg,
493 			   __u16 *val)
494 {
495 	struct usb_device *dev = mcs->port->serial->dev;
496 	struct usb_ctrlrequest *dr = mcs->dr;
497 	unsigned char *buffer = mcs->ctrl_buf;
498 	int ret;
499 
500 	dr->bRequestType = MCS_RD_RTYPE;
501 	dr->bRequest = MCS_RDREQ;
502 	dr->wValue = cpu_to_le16(Wval);	/* 0 */
503 	dr->wIndex = cpu_to_le16(reg);
504 	dr->wLength = cpu_to_le16(2);
505 
506 	usb_fill_control_urb(mcs->control_urb, dev, usb_rcvctrlpipe(dev, 0),
507 			     (unsigned char *)dr, buffer, 2,
508 			     mos7840_control_callback, mcs);
509 	mcs->control_urb->transfer_buffer_length = 2;
510 	ret = usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
511 	return ret;
512 }
513 
514 /*****************************************************************************
515  * mos7840_interrupt_callback
516  *	this is the callback function for when we have received data on the
517  *	interrupt endpoint.
518  *****************************************************************************/
519 
520 static void mos7840_interrupt_callback(struct urb *urb)
521 {
522 	int result;
523 	int length;
524 	struct moschip_port *mos7840_port;
525 	struct usb_serial *serial;
526 	__u16 Data;
527 	unsigned char *data;
528 	__u8 sp[5], st;
529 	int i, rv = 0;
530 	__u16 wval, wreg = 0;
531 	int status = urb->status;
532 
533 	dbg("%s", " : Entering\n");
534 
535 	switch (status) {
536 	case 0:
537 		/* success */
538 		break;
539 	case -ECONNRESET:
540 	case -ENOENT:
541 	case -ESHUTDOWN:
542 		/* this urb is terminated, clean up */
543 		dbg("%s - urb shutting down with status: %d", __func__,
544 		    status);
545 		return;
546 	default:
547 		dbg("%s - nonzero urb status received: %d", __func__,
548 		    status);
549 		goto exit;
550 	}
551 
552 	length = urb->actual_length;
553 	data = urb->transfer_buffer;
554 
555 	serial = urb->context;
556 
557 	/* Moschip get 5 bytes
558 	 * Byte 1 IIR Port 1 (port.number is 0)
559 	 * Byte 2 IIR Port 2 (port.number is 1)
560 	 * Byte 3 IIR Port 3 (port.number is 2)
561 	 * Byte 4 IIR Port 4 (port.number is 3)
562 	 * Byte 5 FIFO status for both */
563 
564 	if (length && length > 5) {
565 		dbg("%s \n", "Wrong data !!!");
566 		return;
567 	}
568 
569 	sp[0] = (__u8) data[0];
570 	sp[1] = (__u8) data[1];
571 	sp[2] = (__u8) data[2];
572 	sp[3] = (__u8) data[3];
573 	st = (__u8) data[4];
574 
575 	for (i = 0; i < serial->num_ports; i++) {
576 		mos7840_port = mos7840_get_port_private(serial->port[i]);
577 		wval =
578 		    (((__u16) serial->port[i]->number -
579 		      (__u16) (serial->minor)) + 1) << 8;
580 		if (mos7840_port->open) {
581 			if (sp[i] & 0x01) {
582 				dbg("SP%d No Interrupt !!!\n", i);
583 			} else {
584 				switch (sp[i] & 0x0f) {
585 				case SERIAL_IIR_RLS:
586 					dbg("Serial Port %d: Receiver status error or ", i);
587 					dbg("address bit detected in 9-bit mode\n");
588 					mos7840_port->MsrLsr = 1;
589 					wreg = LINE_STATUS_REGISTER;
590 					break;
591 				case SERIAL_IIR_MS:
592 					dbg("Serial Port %d: Modem status change\n", i);
593 					mos7840_port->MsrLsr = 0;
594 					wreg = MODEM_STATUS_REGISTER;
595 					break;
596 				}
597 				spin_lock(&mos7840_port->pool_lock);
598 				if (!mos7840_port->zombie) {
599 					rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
600 				} else {
601 					spin_unlock(&mos7840_port->pool_lock);
602 					return;
603 				}
604 				spin_unlock(&mos7840_port->pool_lock);
605 			}
606 		}
607 	}
608 	if (!(rv < 0))
609 		/* the completion handler for the control urb will resubmit */
610 		return;
611 exit:
612 	result = usb_submit_urb(urb, GFP_ATOMIC);
613 	if (result) {
614 		dev_err(&urb->dev->dev,
615 			"%s - Error %d submitting interrupt urb\n",
616 			__func__, result);
617 	}
618 }
619 
620 static int mos7840_port_paranoia_check(struct usb_serial_port *port,
621 				       const char *function)
622 {
623 	if (!port) {
624 		dbg("%s - port == NULL", function);
625 		return -1;
626 	}
627 	if (!port->serial) {
628 		dbg("%s - port->serial == NULL", function);
629 		return -1;
630 	}
631 
632 	return 0;
633 }
634 
635 /* Inline functions to check the sanity of a pointer that is passed to us */
636 static int mos7840_serial_paranoia_check(struct usb_serial *serial,
637 					 const char *function)
638 {
639 	if (!serial) {
640 		dbg("%s - serial == NULL", function);
641 		return -1;
642 	}
643 	if (!serial->type) {
644 		dbg("%s - serial->type == NULL!", function);
645 		return -1;
646 	}
647 
648 	return 0;
649 }
650 
651 static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
652 						 const char *function)
653 {
654 	/* if no port was specified, or it fails a paranoia check */
655 	if (!port ||
656 	    mos7840_port_paranoia_check(port, function) ||
657 	    mos7840_serial_paranoia_check(port->serial, function)) {
658 		/* then say that we don't have a valid usb_serial thing,
659 		 * which will end up genrating -ENODEV return values */
660 		return NULL;
661 	}
662 
663 	return port->serial;
664 }
665 
666 /*****************************************************************************
667  * mos7840_bulk_in_callback
668  *	this is the callback function for when we have received data on the
669  *	bulk in endpoint.
670  *****************************************************************************/
671 
672 static void mos7840_bulk_in_callback(struct urb *urb)
673 {
674 	int retval;
675 	unsigned char *data;
676 	struct usb_serial *serial;
677 	struct usb_serial_port *port;
678 	struct moschip_port *mos7840_port;
679 	struct tty_struct *tty;
680 	int status = urb->status;
681 
682 	if (status) {
683 		dbg("nonzero read bulk status received: %d", status);
684 		return;
685 	}
686 
687 	mos7840_port = urb->context;
688 	if (!mos7840_port) {
689 		dbg("%s", "NULL mos7840_port pointer \n");
690 		return;
691 	}
692 
693 	port = (struct usb_serial_port *)mos7840_port->port;
694 	if (mos7840_port_paranoia_check(port, __func__)) {
695 		dbg("%s", "Port Paranoia failed \n");
696 		return;
697 	}
698 
699 	serial = mos7840_get_usb_serial(port, __func__);
700 	if (!serial) {
701 		dbg("%s\n", "Bad serial pointer ");
702 		return;
703 	}
704 
705 	dbg("%s\n", "Entering... \n");
706 
707 	data = urb->transfer_buffer;
708 
709 	dbg("%s", "Entering ........... \n");
710 
711 	if (urb->actual_length) {
712 		tty = tty_port_tty_get(&mos7840_port->port->port);
713 		if (tty) {
714 			tty_buffer_request_room(tty, urb->actual_length);
715 			tty_insert_flip_string(tty, data, urb->actual_length);
716 			dbg(" %s \n", data);
717 			tty_flip_buffer_push(tty);
718 			tty_kref_put(tty);
719 		}
720 		mos7840_port->icount.rx += urb->actual_length;
721 		smp_wmb();
722 		dbg("mos7840_port->icount.rx is %d:\n",
723 		    mos7840_port->icount.rx);
724 	}
725 
726 	if (!mos7840_port->read_urb) {
727 		dbg("%s", "URB KILLED !!!\n");
728 		return;
729 	}
730 
731 
732 	mos7840_port->read_urb->dev = serial->dev;
733 
734 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
735 
736 	if (retval) {
737 		dbg(" usb_submit_urb(read bulk) failed, retval = %d",
738 		 retval);
739 	}
740 }
741 
742 /*****************************************************************************
743  * mos7840_bulk_out_data_callback
744  *	this is the callback function for when we have finished sending
745  *	serial data on the bulk out endpoint.
746  *****************************************************************************/
747 
748 static void mos7840_bulk_out_data_callback(struct urb *urb)
749 {
750 	struct moschip_port *mos7840_port;
751 	struct tty_struct *tty;
752 	int status = urb->status;
753 	int i;
754 
755 	mos7840_port = urb->context;
756 	spin_lock(&mos7840_port->pool_lock);
757 	for (i = 0; i < NUM_URBS; i++) {
758 		if (urb == mos7840_port->write_urb_pool[i]) {
759 			mos7840_port->busy[i] = 0;
760 			break;
761 		}
762 	}
763 	spin_unlock(&mos7840_port->pool_lock);
764 
765 	if (status) {
766 		dbg("nonzero write bulk status received:%d\n", status);
767 		return;
768 	}
769 
770 	if (mos7840_port_paranoia_check(mos7840_port->port, __func__)) {
771 		dbg("%s", "Port Paranoia failed \n");
772 		return;
773 	}
774 
775 	dbg("%s \n", "Entering .........");
776 
777 	tty = tty_port_tty_get(&mos7840_port->port->port);
778 	if (tty && mos7840_port->open)
779 		tty_wakeup(tty);
780 	tty_kref_put(tty);
781 
782 }
783 
784 /************************************************************************/
785 /*       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       */
786 /************************************************************************/
787 #ifdef MCSSerialProbe
788 static int mos7840_serial_probe(struct usb_serial *serial,
789 				const struct usb_device_id *id)
790 {
791 
792 	/*need to implement the mode_reg reading and updating\
793 	   structures usb_serial_ device_type\
794 	   (i.e num_ports, num_bulkin,bulkout etc) */
795 	/* Also we can update the changes  attach */
796 	return 1;
797 }
798 #endif
799 
800 /*****************************************************************************
801  * mos7840_open
802  *	this function is called by the tty driver when a port is opened
803  *	If successful, we return 0
804  *	Otherwise we return a negative error number.
805  *****************************************************************************/
806 
807 static int mos7840_open(struct tty_struct *tty,
808 			struct usb_serial_port *port, struct file *filp)
809 {
810 	int response;
811 	int j;
812 	struct usb_serial *serial;
813 	struct urb *urb;
814 	__u16 Data;
815 	int status;
816 	struct moschip_port *mos7840_port;
817 	struct moschip_port *port0;
818 
819 	if (mos7840_port_paranoia_check(port, __func__)) {
820 		dbg("%s", "Port Paranoia failed \n");
821 		return -ENODEV;
822 	}
823 
824 	serial = port->serial;
825 
826 	if (mos7840_serial_paranoia_check(serial, __func__)) {
827 		dbg("%s", "Serial Paranoia failed \n");
828 		return -ENODEV;
829 	}
830 
831 	mos7840_port = mos7840_get_port_private(port);
832 	port0 = mos7840_get_port_private(serial->port[0]);
833 
834 	if (mos7840_port == NULL || port0 == NULL)
835 		return -ENODEV;
836 
837 	usb_clear_halt(serial->dev, port->write_urb->pipe);
838 	usb_clear_halt(serial->dev, port->read_urb->pipe);
839 	port0->open_ports++;
840 
841 	/* Initialising the write urb pool */
842 	for (j = 0; j < NUM_URBS; ++j) {
843 		urb = usb_alloc_urb(0, GFP_KERNEL);
844 		mos7840_port->write_urb_pool[j] = urb;
845 
846 		if (urb == NULL) {
847 			dev_err(&port->dev, "No more urbs???\n");
848 			continue;
849 		}
850 
851 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
852 								GFP_KERNEL);
853 		if (!urb->transfer_buffer) {
854 			usb_free_urb(urb);
855 			mos7840_port->write_urb_pool[j] = NULL;
856 			dev_err(&port->dev,
857 				"%s-out of memory for urb buffers.\n",
858 				__func__);
859 			continue;
860 		}
861 	}
862 
863 /*****************************************************************************
864  * Initialize MCS7840 -- Write Init values to corresponding Registers
865  *
866  * Register Index
867  * 1 : IER
868  * 2 : FCR
869  * 3 : LCR
870  * 4 : MCR
871  *
872  * 0x08 : SP1/2 Control Reg
873  *****************************************************************************/
874 
875 	/* NEED to check the following Block */
876 
877 	Data = 0x0;
878 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
879 	if (status < 0) {
880 		dbg("Reading Spreg failed\n");
881 		return -1;
882 	}
883 	Data |= 0x80;
884 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
885 	if (status < 0) {
886 		dbg("writing Spreg failed\n");
887 		return -1;
888 	}
889 
890 	Data &= ~0x80;
891 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
892 	if (status < 0) {
893 		dbg("writing Spreg failed\n");
894 		return -1;
895 	}
896 	/* End of block to be checked */
897 
898 	Data = 0x0;
899 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
900 									&Data);
901 	if (status < 0) {
902 		dbg("Reading Controlreg failed\n");
903 		return -1;
904 	}
905 	Data |= 0x08;		/* Driver done bit */
906 	Data |= 0x20;		/* rx_disable */
907 	status = mos7840_set_reg_sync(port,
908 				mos7840_port->ControlRegOffset, Data);
909 	if (status < 0) {
910 		dbg("writing Controlreg failed\n");
911 		return -1;
912 	}
913 	/* do register settings here */
914 	/* Set all regs to the device default values. */
915 	/***********************************
916 	 * First Disable all interrupts.
917 	 ***********************************/
918 	Data = 0x00;
919 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
920 	if (status < 0) {
921 		dbg("disableing interrupts failed\n");
922 		return -1;
923 	}
924 	/* Set FIFO_CONTROL_REGISTER to the default value */
925 	Data = 0x00;
926 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
927 	if (status < 0) {
928 		dbg("Writing FIFO_CONTROL_REGISTER  failed\n");
929 		return -1;
930 	}
931 
932 	Data = 0xcf;
933 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
934 	if (status < 0) {
935 		dbg("Writing FIFO_CONTROL_REGISTER  failed\n");
936 		return -1;
937 	}
938 
939 	Data = 0x03;
940 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
941 	mos7840_port->shadowLCR = Data;
942 
943 	Data = 0x0b;
944 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
945 	mos7840_port->shadowMCR = Data;
946 
947 	Data = 0x00;
948 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
949 	mos7840_port->shadowLCR = Data;
950 
951 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
952 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
953 
954 	Data = 0x0c;
955 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
956 
957 	Data = 0x0;
958 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
959 
960 	Data = 0x00;
961 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
962 
963 	Data = Data & ~SERIAL_LCR_DLAB;
964 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
965 	mos7840_port->shadowLCR = Data;
966 
967 	/* clearing Bulkin and Bulkout Fifo */
968 	Data = 0x0;
969 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
970 
971 	Data = Data | 0x0c;
972 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
973 
974 	Data = Data & ~0x0c;
975 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
976 	/* Finally enable all interrupts */
977 	Data = 0x0c;
978 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
979 
980 	/* clearing rx_disable */
981 	Data = 0x0;
982 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
983 									&Data);
984 	Data = Data & ~0x20;
985 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
986 									Data);
987 
988 	/* rx_negate */
989 	Data = 0x0;
990 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
991 									&Data);
992 	Data = Data | 0x10;
993 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
994 									Data);
995 
996 	/* force low_latency on so that our tty_push actually forces *
997 	 * the data through,otherwise it is scheduled, and with      *
998 	 * high data rates (like with OHCI) data can get lost.       */
999 	if (tty)
1000 		tty->low_latency = 1;
1001 
1002 	/* Check to see if we've set up our endpoint info yet    *
1003 	 * (can't set it up in mos7840_startup as the structures *
1004 	 * were not set up at that time.)                        */
1005 	if (port0->open_ports == 1) {
1006 		if (serial->port[0]->interrupt_in_buffer == NULL) {
1007 			/* set up interrupt urb */
1008 			usb_fill_int_urb(serial->port[0]->interrupt_in_urb,
1009 				serial->dev,
1010 				usb_rcvintpipe(serial->dev,
1011 				serial->port[0]->interrupt_in_endpointAddress),
1012 				serial->port[0]->interrupt_in_buffer,
1013 				serial->port[0]->interrupt_in_urb->
1014 				transfer_buffer_length,
1015 				mos7840_interrupt_callback,
1016 				serial,
1017 				serial->port[0]->interrupt_in_urb->interval);
1018 
1019 			/* start interrupt read for mos7840               *
1020 			 * will continue as long as mos7840 is connected  */
1021 
1022 			response =
1023 			    usb_submit_urb(serial->port[0]->interrupt_in_urb,
1024 					   GFP_KERNEL);
1025 			if (response) {
1026 				dev_err(&port->dev, "%s - Error %d submitting "
1027 					"interrupt urb\n", __func__, response);
1028 			}
1029 
1030 		}
1031 
1032 	}
1033 
1034 	/* see if we've set up our endpoint info yet   *
1035 	 * (can't set it up in mos7840_startup as the  *
1036 	 * structures were not set up at that time.)   */
1037 
1038 	dbg("port number is %d \n", port->number);
1039 	dbg("serial number is %d \n", port->serial->minor);
1040 	dbg("Bulkin endpoint is %d \n", port->bulk_in_endpointAddress);
1041 	dbg("BulkOut endpoint is %d \n", port->bulk_out_endpointAddress);
1042 	dbg("Interrupt endpoint is %d \n", port->interrupt_in_endpointAddress);
1043 	dbg("port's number in the device is %d\n", mos7840_port->port_num);
1044 	mos7840_port->read_urb = port->read_urb;
1045 
1046 	/* set up our bulk in urb */
1047 
1048 	usb_fill_bulk_urb(mos7840_port->read_urb,
1049 			  serial->dev,
1050 			  usb_rcvbulkpipe(serial->dev,
1051 					  port->bulk_in_endpointAddress),
1052 			  port->bulk_in_buffer,
1053 			  mos7840_port->read_urb->transfer_buffer_length,
1054 			  mos7840_bulk_in_callback, mos7840_port);
1055 
1056 	dbg("mos7840_open: bulkin endpoint is %d\n",
1057 	    port->bulk_in_endpointAddress);
1058 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1059 	if (response) {
1060 		dev_err(&port->dev, "%s - Error %d submitting control urb\n",
1061 			__func__, response);
1062 	}
1063 
1064 	/* initialize our wait queues */
1065 	init_waitqueue_head(&mos7840_port->wait_chase);
1066 	init_waitqueue_head(&mos7840_port->delta_msr_wait);
1067 
1068 	/* initialize our icount structure */
1069 	memset(&(mos7840_port->icount), 0x00, sizeof(mos7840_port->icount));
1070 
1071 	/* initialize our port settings */
1072 	/* Must set to enable ints! */
1073 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1074 	/* send a open port command */
1075 	mos7840_port->open = 1;
1076 	/* mos7840_change_port_settings(mos7840_port,old_termios); */
1077 	mos7840_port->icount.tx = 0;
1078 	mos7840_port->icount.rx = 0;
1079 
1080 	dbg("\n\nusb_serial serial:%p       mos7840_port:%p\n      usb_serial_port port:%p\n\n",
1081 				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 zero.
1095  *****************************************************************************/
1096 
1097 static int mos7840_chars_in_buffer(struct tty_struct *tty)
1098 {
1099 	struct usb_serial_port *port = tty->driver_data;
1100 	int i;
1101 	int chars = 0;
1102 	unsigned long flags;
1103 	struct moschip_port *mos7840_port;
1104 
1105 	dbg("%s \n", " mos7840_chars_in_buffer:entering ...........");
1106 
1107 	if (mos7840_port_paranoia_check(port, __func__)) {
1108 		dbg("%s", "Invalid port \n");
1109 		return 0;
1110 	}
1111 
1112 	mos7840_port = mos7840_get_port_private(port);
1113 	if (mos7840_port == NULL) {
1114 		dbg("%s \n", "mos7840_break:leaving ...........");
1115 		return 0;
1116 	}
1117 
1118 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1119 	for (i = 0; i < NUM_URBS; ++i)
1120 		if (mos7840_port->busy[i])
1121 			chars += URB_TRANSFER_BUFFER_SIZE;
1122 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1123 	dbg("%s - returns %d", __func__, chars);
1124 	return chars;
1125 
1126 }
1127 
1128 /************************************************************************
1129  *
1130  * mos7840_block_until_tx_empty
1131  *
1132  *	This function will block the close until one of the following:
1133  *		1. TX count are 0
1134  *		2. The mos7840 has stopped
1135  *		3. A timeout of 3 seconds without activity has expired
1136  *
1137  ************************************************************************/
1138 static void mos7840_block_until_tx_empty(struct tty_struct *tty,
1139 				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(tty);
1148 
1149 		/* Check for Buffer status */
1150 		if (count <= 0)
1151 			return;
1152 
1153 		/* Block the thread for a while */
1154 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1155 					       timeout);
1156 
1157 		/* No activity.. count down section */
1158 		wait--;
1159 		if (wait == 0) {
1160 			dbg("%s - TIMEOUT", __func__);
1161 			return;
1162 		} else {
1163 			/* Reset timeout value back to seconds */
1164 			wait = 30;
1165 		}
1166 	}
1167 }
1168 
1169 /*****************************************************************************
1170  * mos7840_close
1171  *	this function is called by the tty driver when a port is closed
1172  *****************************************************************************/
1173 
1174 static void mos7840_close(struct tty_struct *tty,
1175 			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, __func__)) {
1186 		dbg("%s", "Port Paranoia failed \n");
1187 		return;
1188 	}
1189 
1190 	serial = mos7840_get_usb_serial(port, __func__);
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(tty, mos7840_port);
1219 
1220 	/* While closing port, shutdown all bulk read, write  *
1221 	 * and interrupt read if they exists                  */
1222 	if (serial->dev) {
1223 		if (mos7840_port->write_urb) {
1224 			dbg("%s", "Shutdown bulk write\n");
1225 			usb_kill_urb(mos7840_port->write_urb);
1226 		}
1227 		if (mos7840_port->read_urb) {
1228 			dbg("%s", "Shutdown bulk read\n");
1229 			usb_kill_urb(mos7840_port->read_urb);
1230 		}
1231 		if ((&mos7840_port->control_urb)) {
1232 			dbg("%s", "Shutdown control read\n");
1233 			/*/      usb_kill_urb (mos7840_port->control_urb); */
1234 		}
1235 	}
1236 /*      if(mos7840_port->ctrl_buf != NULL) */
1237 /*              kfree(mos7840_port->ctrl_buf); */
1238 	port0->open_ports--;
1239 	dbg("mos7840_num_open_ports in close%d:in port%d\n",
1240 	    port0->open_ports, port->number);
1241 	if (port0->open_ports == 0) {
1242 		if (serial->port[0]->interrupt_in_urb) {
1243 			dbg("%s", "Shutdown interrupt_in_urb\n");
1244 			usb_kill_urb(serial->port[0]->interrupt_in_urb);
1245 		}
1246 	}
1247 
1248 	if (mos7840_port->write_urb) {
1249 		/* if this urb had a transfer buffer already (old tx) free it */
1250 		if (mos7840_port->write_urb->transfer_buffer != NULL)
1251 			kfree(mos7840_port->write_urb->transfer_buffer);
1252 		usb_free_urb(mos7840_port->write_urb);
1253 	}
1254 
1255 	Data = 0x0;
1256 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1257 
1258 	Data = 0x00;
1259 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1260 
1261 	mos7840_port->open = 0;
1262 
1263 	dbg("%s \n", "Leaving ............");
1264 }
1265 
1266 /************************************************************************
1267  *
1268  * mos7840_block_until_chase_response
1269  *
1270  *	This function will block the close until one of the following:
1271  *		1. Response to our Chase comes from mos7840
1272  *		2. A timeout of 10 seconds without activity has expired
1273  *		   (1K of mos7840 data @ 2400 baud ==> 4 sec to empty)
1274  *
1275  ************************************************************************/
1276 
1277 static void mos7840_block_until_chase_response(struct tty_struct *tty,
1278 					struct moschip_port *mos7840_port)
1279 {
1280 	int timeout = 1 * HZ;
1281 	int wait = 10;
1282 	int count;
1283 
1284 	while (1) {
1285 		count = mos7840_chars_in_buffer(tty);
1286 
1287 		/* Check for Buffer status */
1288 		if (count <= 0)
1289 			return;
1290 
1291 		/* Block the thread for a while */
1292 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1293 					       timeout);
1294 		/* No activity.. count down section */
1295 		wait--;
1296 		if (wait == 0) {
1297 			dbg("%s - TIMEOUT", __func__);
1298 			return;
1299 		} else {
1300 			/* Reset timeout value back to seconds */
1301 			wait = 10;
1302 		}
1303 	}
1304 
1305 }
1306 
1307 /*****************************************************************************
1308  * mos7840_break
1309  *	this function sends a break to the port
1310  *****************************************************************************/
1311 static void mos7840_break(struct tty_struct *tty, int break_state)
1312 {
1313 	struct usb_serial_port *port = tty->driver_data;
1314 	unsigned char data;
1315 	struct usb_serial *serial;
1316 	struct moschip_port *mos7840_port;
1317 
1318 	dbg("%s \n", "Entering ...........");
1319 	dbg("mos7840_break: Start\n");
1320 
1321 	if (mos7840_port_paranoia_check(port, __func__)) {
1322 		dbg("%s", "Port Paranoia failed \n");
1323 		return;
1324 	}
1325 
1326 	serial = mos7840_get_usb_serial(port, __func__);
1327 	if (!serial) {
1328 		dbg("%s", "Serial Paranoia failed \n");
1329 		return;
1330 	}
1331 
1332 	mos7840_port = mos7840_get_port_private(port);
1333 
1334 	if (mos7840_port == NULL)
1335 		return;
1336 
1337 	if (serial->dev)
1338 		/* flush and block until tx is empty */
1339 		mos7840_block_until_chase_response(tty, mos7840_port);
1340 
1341 	if (break_state == -1)
1342 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
1343 	else
1344 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
1345 
1346 	mos7840_port->shadowLCR = data;
1347 	dbg("mcs7840_break mos7840_port->shadowLCR is %x\n",
1348 	    mos7840_port->shadowLCR);
1349 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
1350 			     mos7840_port->shadowLCR);
1351 
1352 	return;
1353 }
1354 
1355 /*****************************************************************************
1356  * mos7840_write_room
1357  *	this function is called by the tty driver when it wants to know how many
1358  *	bytes of data we can accept for a specific port.
1359  *	If successful, we return the amount of room that we have for this port
1360  *	Otherwise we return a negative error number.
1361  *****************************************************************************/
1362 
1363 static int mos7840_write_room(struct tty_struct *tty)
1364 {
1365 	struct usb_serial_port *port = tty->driver_data;
1366 	int i;
1367 	int room = 0;
1368 	unsigned long flags;
1369 	struct moschip_port *mos7840_port;
1370 
1371 	dbg("%s \n", " mos7840_write_room:entering ...........");
1372 
1373 	if (mos7840_port_paranoia_check(port, __func__)) {
1374 		dbg("%s", "Invalid port \n");
1375 		dbg("%s \n", " mos7840_write_room:leaving ...........");
1376 		return -1;
1377 	}
1378 
1379 	mos7840_port = mos7840_get_port_private(port);
1380 	if (mos7840_port == NULL) {
1381 		dbg("%s \n", "mos7840_break:leaving ...........");
1382 		return -1;
1383 	}
1384 
1385 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1386 	for (i = 0; i < NUM_URBS; ++i) {
1387 		if (!mos7840_port->busy[i])
1388 			room += URB_TRANSFER_BUFFER_SIZE;
1389 	}
1390 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1391 
1392 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
1393 	dbg("%s - returns %d", __func__, room);
1394 	return room;
1395 
1396 }
1397 
1398 /*****************************************************************************
1399  * mos7840_write
1400  *	this function is called by the tty driver when data should be written to
1401  *	the port.
1402  *	If successful, we return the number of bytes written, otherwise we
1403  *      return a negative error number.
1404  *****************************************************************************/
1405 
1406 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
1407 			 const unsigned char *data, int count)
1408 {
1409 	int status;
1410 	int i;
1411 	int bytes_sent = 0;
1412 	int transfer_size;
1413 	unsigned long flags;
1414 
1415 	struct moschip_port *mos7840_port;
1416 	struct usb_serial *serial;
1417 	struct urb *urb;
1418 	/* __u16 Data; */
1419 	const unsigned char *current_position = data;
1420 	unsigned char *data1;
1421 	dbg("%s \n", "entering ...........");
1422 	/* dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
1423 					mos7840_port->shadowLCR); */
1424 
1425 #ifdef NOTMOS7840
1426 	Data = 0x00;
1427 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1428 	mos7840_port->shadowLCR = Data;
1429 	dbg("mos7840_write: LINE_CONTROL_REGISTER is %x\n", Data);
1430 	dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
1431 	    mos7840_port->shadowLCR);
1432 
1433 	/* Data = 0x03; */
1434 	/* status = mos7840_set_uart_reg(port,LINE_CONTROL_REGISTER,Data); */
1435 	/* mos7840_port->shadowLCR=Data;//Need to add later */
1436 
1437 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
1438 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1439 
1440 	/* Data = 0x0c; */
1441 	/* status = mos7840_set_uart_reg(port,DIVISOR_LATCH_LSB,Data); */
1442 	Data = 0x00;
1443 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_LSB, &Data);
1444 	dbg("mos7840_write:DLL value is %x\n", Data);
1445 
1446 	Data = 0x0;
1447 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_MSB, &Data);
1448 	dbg("mos7840_write:DLM value is %x\n", Data);
1449 
1450 	Data = Data & ~SERIAL_LCR_DLAB;
1451 	dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
1452 	    mos7840_port->shadowLCR);
1453 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1454 #endif
1455 
1456 	if (mos7840_port_paranoia_check(port, __func__)) {
1457 		dbg("%s", "Port Paranoia failed \n");
1458 		return -1;
1459 	}
1460 
1461 	serial = port->serial;
1462 	if (mos7840_serial_paranoia_check(serial, __func__)) {
1463 		dbg("%s", "Serial Paranoia failed \n");
1464 		return -1;
1465 	}
1466 
1467 	mos7840_port = mos7840_get_port_private(port);
1468 	if (mos7840_port == NULL) {
1469 		dbg("%s", "mos7840_port is NULL\n");
1470 		return -1;
1471 	}
1472 
1473 	/* try to find a free urb in the list */
1474 	urb = NULL;
1475 
1476 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1477 	for (i = 0; i < NUM_URBS; ++i) {
1478 		if (!mos7840_port->busy[i]) {
1479 			mos7840_port->busy[i] = 1;
1480 			urb = mos7840_port->write_urb_pool[i];
1481 			dbg("\nURB:%d", i);
1482 			break;
1483 		}
1484 	}
1485 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1486 
1487 	if (urb == NULL) {
1488 		dbg("%s - no more free urbs", __func__);
1489 		goto exit;
1490 	}
1491 
1492 	if (urb->transfer_buffer == NULL) {
1493 		urb->transfer_buffer =
1494 		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
1495 
1496 		if (urb->transfer_buffer == NULL) {
1497 			dev_err(&port->dev, "%s no more kernel memory...\n",
1498 				__func__);
1499 			goto exit;
1500 		}
1501 	}
1502 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1503 
1504 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1505 
1506 	/* fill urb with data and submit  */
1507 	usb_fill_bulk_urb(urb,
1508 			  serial->dev,
1509 			  usb_sndbulkpipe(serial->dev,
1510 					  port->bulk_out_endpointAddress),
1511 			  urb->transfer_buffer,
1512 			  transfer_size,
1513 			  mos7840_bulk_out_data_callback, mos7840_port);
1514 
1515 	data1 = urb->transfer_buffer;
1516 	dbg("\nbulkout endpoint is %d", port->bulk_out_endpointAddress);
1517 
1518 	/* send it down the pipe */
1519 	status = usb_submit_urb(urb, GFP_ATOMIC);
1520 
1521 	if (status) {
1522 		mos7840_port->busy[i] = 0;
1523 		dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed "
1524 			"with status = %d\n", __func__, status);
1525 		bytes_sent = status;
1526 		goto exit;
1527 	}
1528 	bytes_sent = transfer_size;
1529 	mos7840_port->icount.tx += transfer_size;
1530 	smp_wmb();
1531 	dbg("mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);
1532 exit:
1533 	return bytes_sent;
1534 
1535 }
1536 
1537 /*****************************************************************************
1538  * mos7840_throttle
1539  *	this function is called by the tty driver when it wants to stop the data
1540  *	being read from the port.
1541  *****************************************************************************/
1542 
1543 static void mos7840_throttle(struct tty_struct *tty)
1544 {
1545 	struct usb_serial_port *port = tty->driver_data;
1546 	struct moschip_port *mos7840_port;
1547 	int status;
1548 
1549 	if (mos7840_port_paranoia_check(port, __func__)) {
1550 		dbg("%s", "Invalid port \n");
1551 		return;
1552 	}
1553 
1554 	dbg("- port %d\n", port->number);
1555 
1556 	mos7840_port = mos7840_get_port_private(port);
1557 
1558 	if (mos7840_port == NULL)
1559 		return;
1560 
1561 	if (!mos7840_port->open) {
1562 		dbg("%s\n", "port not opened");
1563 		return;
1564 	}
1565 
1566 	dbg("%s", "Entering .......... \n");
1567 
1568 	/* if we are implementing XON/XOFF, send the stop character */
1569 	if (I_IXOFF(tty)) {
1570 		unsigned char stop_char = STOP_CHAR(tty);
1571 		status = mos7840_write(tty, port, &stop_char, 1);
1572 		if (status <= 0)
1573 			return;
1574 	}
1575 	/* if we are implementing RTS/CTS, toggle that line */
1576 	if (tty->termios->c_cflag & CRTSCTS) {
1577 		mos7840_port->shadowMCR &= ~MCR_RTS;
1578 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1579 					 mos7840_port->shadowMCR);
1580 		if (status < 0)
1581 			return;
1582 	}
1583 
1584 	return;
1585 }
1586 
1587 /*****************************************************************************
1588  * mos7840_unthrottle
1589  *	this function is called by the tty driver when it wants to resume
1590  *	the data being read from the port (called after mos7840_throttle is
1591  *	called)
1592  *****************************************************************************/
1593 static void mos7840_unthrottle(struct tty_struct *tty)
1594 {
1595 	struct usb_serial_port *port = tty->driver_data;
1596 	int status;
1597 	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
1598 
1599 	if (mos7840_port_paranoia_check(port, __func__)) {
1600 		dbg("%s", "Invalid port \n");
1601 		return;
1602 	}
1603 
1604 	if (mos7840_port == NULL)
1605 		return;
1606 
1607 	if (!mos7840_port->open) {
1608 		dbg("%s - port not opened", __func__);
1609 		return;
1610 	}
1611 
1612 	dbg("%s", "Entering .......... \n");
1613 
1614 	/* if we are implementing XON/XOFF, send the start character */
1615 	if (I_IXOFF(tty)) {
1616 		unsigned char start_char = START_CHAR(tty);
1617 		status = mos7840_write(tty, port, &start_char, 1);
1618 		if (status <= 0)
1619 			return;
1620 	}
1621 
1622 	/* if we are implementing RTS/CTS, toggle that line */
1623 	if (tty->termios->c_cflag & CRTSCTS) {
1624 		mos7840_port->shadowMCR |= MCR_RTS;
1625 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1626 					 mos7840_port->shadowMCR);
1627 		if (status < 0)
1628 			return;
1629 	}
1630 }
1631 
1632 static int mos7840_tiocmget(struct tty_struct *tty, struct file *file)
1633 {
1634 	struct usb_serial_port *port = tty->driver_data;
1635 	struct moschip_port *mos7840_port;
1636 	unsigned int result;
1637 	__u16 msr;
1638 	__u16 mcr;
1639 	int status;
1640 	mos7840_port = mos7840_get_port_private(port);
1641 
1642 	dbg("%s - port %d", __func__, port->number);
1643 
1644 	if (mos7840_port == NULL)
1645 		return -ENODEV;
1646 
1647 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
1648 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1649 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1650 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1651 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1652 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1653 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1654 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1655 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1656 
1657 	dbg("%s - 0x%04X", __func__, result);
1658 
1659 	return result;
1660 }
1661 
1662 static int mos7840_tiocmset(struct tty_struct *tty, struct file *file,
1663 			    unsigned int set, unsigned int clear)
1664 {
1665 	struct usb_serial_port *port = tty->driver_data;
1666 	struct moschip_port *mos7840_port;
1667 	unsigned int mcr;
1668 	int status;
1669 
1670 	dbg("%s - port %d", __func__, port->number);
1671 
1672 	mos7840_port = mos7840_get_port_private(port);
1673 
1674 	if (mos7840_port == NULL)
1675 		return -ENODEV;
1676 
1677 	/* FIXME: What locks the port registers ? */
1678 	mcr = mos7840_port->shadowMCR;
1679 	if (clear & TIOCM_RTS)
1680 		mcr &= ~MCR_RTS;
1681 	if (clear & TIOCM_DTR)
1682 		mcr &= ~MCR_DTR;
1683 	if (clear & TIOCM_LOOP)
1684 		mcr &= ~MCR_LOOPBACK;
1685 
1686 	if (set & TIOCM_RTS)
1687 		mcr |= MCR_RTS;
1688 	if (set & TIOCM_DTR)
1689 		mcr |= MCR_DTR;
1690 	if (set & TIOCM_LOOP)
1691 		mcr |= MCR_LOOPBACK;
1692 
1693 	mos7840_port->shadowMCR = mcr;
1694 
1695 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1696 	if (status < 0) {
1697 		dbg("setting MODEM_CONTROL_REGISTER Failed\n");
1698 		return status;
1699 	}
1700 
1701 	return 0;
1702 }
1703 
1704 /*****************************************************************************
1705  * mos7840_calc_baud_rate_divisor
1706  *	this function calculates the proper baud rate divisor for the specified
1707  *	baud rate.
1708  *****************************************************************************/
1709 static int mos7840_calc_baud_rate_divisor(int baudRate, int *divisor,
1710 					  __u16 *clk_sel_val)
1711 {
1712 
1713 	dbg("%s - %d", __func__, baudRate);
1714 
1715 	if (baudRate <= 115200) {
1716 		*divisor = 115200 / baudRate;
1717 		*clk_sel_val = 0x0;
1718 	}
1719 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1720 		*divisor = 230400 / baudRate;
1721 		*clk_sel_val = 0x10;
1722 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1723 		*divisor = 403200 / baudRate;
1724 		*clk_sel_val = 0x20;
1725 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1726 		*divisor = 460800 / baudRate;
1727 		*clk_sel_val = 0x30;
1728 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1729 		*divisor = 806400 / baudRate;
1730 		*clk_sel_val = 0x40;
1731 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1732 		*divisor = 921600 / baudRate;
1733 		*clk_sel_val = 0x50;
1734 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1735 		*divisor = 1572864 / baudRate;
1736 		*clk_sel_val = 0x60;
1737 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1738 		*divisor = 3145728 / baudRate;
1739 		*clk_sel_val = 0x70;
1740 	}
1741 	return 0;
1742 
1743 #ifdef NOTMCS7840
1744 
1745 	for (i = 0; i < ARRAY_SIZE(mos7840_divisor_table); i++) {
1746 		if (mos7840_divisor_table[i].BaudRate == baudrate) {
1747 			*divisor = mos7840_divisor_table[i].Divisor;
1748 			return 0;
1749 		}
1750 	}
1751 
1752 	/* After trying for all the standard baud rates    *
1753 	 * Try calculating the divisor for this baud rate  */
1754 
1755 	if (baudrate > 75 && baudrate < 230400) {
1756 		/* get the divisor */
1757 		custom = (__u16) (230400L / baudrate);
1758 
1759 		/* Check for round off */
1760 		round1 = (__u16) (2304000L / baudrate);
1761 		round = (__u16) (round1 - (custom * 10));
1762 		if (round > 4)
1763 			custom++;
1764 		*divisor = custom;
1765 
1766 		dbg(" Baud %d = %d\n", baudrate, custom);
1767 		return 0;
1768 	}
1769 
1770 	dbg("%s\n", " Baud calculation Failed...");
1771 	return -1;
1772 #endif
1773 }
1774 
1775 /*****************************************************************************
1776  * mos7840_send_cmd_write_baud_rate
1777  *	this function sends the proper command to change the baud rate of the
1778  *	specified port.
1779  *****************************************************************************/
1780 
1781 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1782 					    int baudRate)
1783 {
1784 	int divisor = 0;
1785 	int status;
1786 	__u16 Data;
1787 	unsigned char number;
1788 	__u16 clk_sel_val;
1789 	struct usb_serial_port *port;
1790 
1791 	if (mos7840_port == NULL)
1792 		return -1;
1793 
1794 	port = (struct usb_serial_port *)mos7840_port->port;
1795 	if (mos7840_port_paranoia_check(port, __func__)) {
1796 		dbg("%s", "Invalid port \n");
1797 		return -1;
1798 	}
1799 
1800 	if (mos7840_serial_paranoia_check(port->serial, __func__)) {
1801 		dbg("%s", "Invalid Serial \n");
1802 		return -1;
1803 	}
1804 
1805 	dbg("%s", "Entering .......... \n");
1806 
1807 	number = mos7840_port->port->number - mos7840_port->port->serial->minor;
1808 
1809 	dbg("%s - port = %d, baud = %d", __func__,
1810 	    mos7840_port->port->number, baudRate);
1811 	/* reset clk_uart_sel in spregOffset */
1812 	if (baudRate > 115200) {
1813 #ifdef HW_flow_control
1814 		/* NOTE: need to see the pther register to modify */
1815 		/* setting h/w flow control bit to 1 */
1816 		Data = 0x2b;
1817 		mos7840_port->shadowMCR = Data;
1818 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1819 									Data);
1820 		if (status < 0) {
1821 			dbg("Writing spreg failed in set_serial_baud\n");
1822 			return -1;
1823 		}
1824 #endif
1825 
1826 	} else {
1827 #ifdef HW_flow_control
1828 		/ *setting h/w flow control bit to 0 */
1829 		Data = 0xb;
1830 		mos7840_port->shadowMCR = Data;
1831 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1832 									Data);
1833 		if (status < 0) {
1834 			dbg("Writing spreg failed in set_serial_baud\n");
1835 			return -1;
1836 		}
1837 #endif
1838 
1839 	}
1840 
1841 	if (1) {		/* baudRate <= 115200) */
1842 		clk_sel_val = 0x0;
1843 		Data = 0x0;
1844 		status = mos7840_calc_baud_rate_divisor(baudRate, &divisor,
1845 						   &clk_sel_val);
1846 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1847 								 &Data);
1848 		if (status < 0) {
1849 			dbg("reading spreg failed in set_serial_baud\n");
1850 			return -1;
1851 		}
1852 		Data = (Data & 0x8f) | clk_sel_val;
1853 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1854 								Data);
1855 		if (status < 0) {
1856 			dbg("Writing spreg failed in set_serial_baud\n");
1857 			return -1;
1858 		}
1859 		/* Calculate the Divisor */
1860 
1861 		if (status) {
1862 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1863 			return status;
1864 		}
1865 		/* Enable access to divisor latch */
1866 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1867 		mos7840_port->shadowLCR = Data;
1868 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1869 
1870 		/* Write the divisor */
1871 		Data = (unsigned char)(divisor & 0xff);
1872 		dbg("set_serial_baud Value to write DLL is %x\n", Data);
1873 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1874 
1875 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1876 		dbg("set_serial_baud Value to write DLM is %x\n", Data);
1877 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1878 
1879 		/* Disable access to divisor latch */
1880 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1881 		mos7840_port->shadowLCR = Data;
1882 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1883 
1884 	}
1885 	return status;
1886 }
1887 
1888 /*****************************************************************************
1889  * mos7840_change_port_settings
1890  *	This routine is called to set the UART on the device to match
1891  *      the specified new settings.
1892  *****************************************************************************/
1893 
1894 static void mos7840_change_port_settings(struct tty_struct *tty,
1895 	struct moschip_port *mos7840_port, struct ktermios *old_termios)
1896 {
1897 	int baud;
1898 	unsigned cflag;
1899 	unsigned iflag;
1900 	__u8 lData;
1901 	__u8 lParity;
1902 	__u8 lStop;
1903 	int status;
1904 	__u16 Data;
1905 	struct usb_serial_port *port;
1906 	struct usb_serial *serial;
1907 
1908 	if (mos7840_port == NULL)
1909 		return;
1910 
1911 	port = (struct usb_serial_port *)mos7840_port->port;
1912 
1913 	if (mos7840_port_paranoia_check(port, __func__)) {
1914 		dbg("%s", "Invalid port \n");
1915 		return;
1916 	}
1917 
1918 	if (mos7840_serial_paranoia_check(port->serial, __func__)) {
1919 		dbg("%s", "Invalid Serial \n");
1920 		return;
1921 	}
1922 
1923 	serial = port->serial;
1924 
1925 	dbg("%s - port %d", __func__, mos7840_port->port->number);
1926 
1927 	if (!mos7840_port->open) {
1928 		dbg("%s - port not opened", __func__);
1929 		return;
1930 	}
1931 
1932 	dbg("%s", "Entering .......... \n");
1933 
1934 	lData = LCR_BITS_8;
1935 	lStop = LCR_STOP_1;
1936 	lParity = LCR_PAR_NONE;
1937 
1938 	cflag = tty->termios->c_cflag;
1939 	iflag = tty->termios->c_iflag;
1940 
1941 	/* Change the number of bits */
1942 	if (cflag & CSIZE) {
1943 		switch (cflag & CSIZE) {
1944 		case CS5:
1945 			lData = LCR_BITS_5;
1946 			break;
1947 
1948 		case CS6:
1949 			lData = LCR_BITS_6;
1950 			break;
1951 
1952 		case CS7:
1953 			lData = LCR_BITS_7;
1954 			break;
1955 		default:
1956 		case CS8:
1957 			lData = LCR_BITS_8;
1958 			break;
1959 		}
1960 	}
1961 	/* Change the Parity bit */
1962 	if (cflag & PARENB) {
1963 		if (cflag & PARODD) {
1964 			lParity = LCR_PAR_ODD;
1965 			dbg("%s - parity = odd", __func__);
1966 		} else {
1967 			lParity = LCR_PAR_EVEN;
1968 			dbg("%s - parity = even", __func__);
1969 		}
1970 
1971 	} else {
1972 		dbg("%s - parity = none", __func__);
1973 	}
1974 
1975 	if (cflag & CMSPAR)
1976 		lParity = lParity | 0x20;
1977 
1978 	/* Change the Stop bit */
1979 	if (cflag & CSTOPB) {
1980 		lStop = LCR_STOP_2;
1981 		dbg("%s - stop bits = 2", __func__);
1982 	} else {
1983 		lStop = LCR_STOP_1;
1984 		dbg("%s - stop bits = 1", __func__);
1985 	}
1986 
1987 	/* Update the LCR with the correct value */
1988 	mos7840_port->shadowLCR &=
1989 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1990 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1991 
1992 	dbg("mos7840_change_port_settings mos7840_port->shadowLCR is %x\n",
1993 	    mos7840_port->shadowLCR);
1994 	/* Disable Interrupts */
1995 	Data = 0x00;
1996 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1997 
1998 	Data = 0x00;
1999 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
2000 
2001 	Data = 0xcf;
2002 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
2003 
2004 	/* Send the updated LCR value to the mos7840 */
2005 	Data = mos7840_port->shadowLCR;
2006 
2007 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
2008 
2009 	Data = 0x00b;
2010 	mos7840_port->shadowMCR = Data;
2011 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2012 	Data = 0x00b;
2013 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2014 
2015 	/* set up the MCR register and send it to the mos7840 */
2016 
2017 	mos7840_port->shadowMCR = MCR_MASTER_IE;
2018 	if (cflag & CBAUD)
2019 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
2020 
2021 	if (cflag & CRTSCTS)
2022 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
2023 	else
2024 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
2025 
2026 	Data = mos7840_port->shadowMCR;
2027 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2028 
2029 	/* Determine divisor based on baud rate */
2030 	baud = tty_get_baud_rate(tty);
2031 
2032 	if (!baud) {
2033 		/* pick a default, any default... */
2034 		dbg("%s\n", "Picked default baud...");
2035 		baud = 9600;
2036 	}
2037 
2038 	dbg("%s - baud rate = %d", __func__, baud);
2039 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
2040 
2041 	/* Enable Interrupts */
2042 	Data = 0x0c;
2043 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
2044 
2045 	if (mos7840_port->read_urb->status != -EINPROGRESS) {
2046 		mos7840_port->read_urb->dev = serial->dev;
2047 
2048 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2049 
2050 		if (status) {
2051 			dbg(" usb_submit_urb(read bulk) failed, status = %d",
2052 			    status);
2053 		}
2054 	}
2055 	wake_up(&mos7840_port->delta_msr_wait);
2056 	mos7840_port->delta_msr_cond = 1;
2057 	dbg("mos7840_change_port_settings mos7840_port->shadowLCR is End %x\n",
2058 	    mos7840_port->shadowLCR);
2059 
2060 	return;
2061 }
2062 
2063 /*****************************************************************************
2064  * mos7840_set_termios
2065  *	this function is called by the tty driver when it wants to change
2066  *	the termios structure
2067  *****************************************************************************/
2068 
2069 static void mos7840_set_termios(struct tty_struct *tty,
2070 				struct usb_serial_port *port,
2071 				struct ktermios *old_termios)
2072 {
2073 	int status;
2074 	unsigned int cflag;
2075 	struct usb_serial *serial;
2076 	struct moschip_port *mos7840_port;
2077 	dbg("mos7840_set_termios: START\n");
2078 	if (mos7840_port_paranoia_check(port, __func__)) {
2079 		dbg("%s", "Invalid port \n");
2080 		return;
2081 	}
2082 
2083 	serial = port->serial;
2084 
2085 	if (mos7840_serial_paranoia_check(serial, __func__)) {
2086 		dbg("%s", "Invalid Serial \n");
2087 		return;
2088 	}
2089 
2090 	mos7840_port = mos7840_get_port_private(port);
2091 
2092 	if (mos7840_port == NULL)
2093 		return;
2094 
2095 	if (!mos7840_port->open) {
2096 		dbg("%s - port not opened", __func__);
2097 		return;
2098 	}
2099 
2100 	dbg("%s\n", "setting termios - ");
2101 
2102 	cflag = tty->termios->c_cflag;
2103 
2104 	dbg("%s - clfag %08x iflag %08x", __func__,
2105 	    tty->termios->c_cflag, RELEVANT_IFLAG(tty->termios->c_iflag));
2106 	dbg("%s - old clfag %08x old iflag %08x", __func__,
2107 	    old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
2108 	dbg("%s - port %d", __func__, port->number);
2109 
2110 	/* change the port settings to the new ones specified */
2111 
2112 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
2113 
2114 	if (!mos7840_port->read_urb) {
2115 		dbg("%s", "URB KILLED !!!!!\n");
2116 		return;
2117 	}
2118 
2119 	if (mos7840_port->read_urb->status != -EINPROGRESS) {
2120 		mos7840_port->read_urb->dev = serial->dev;
2121 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2122 		if (status) {
2123 			dbg(" usb_submit_urb(read bulk) failed, status = %d",
2124 			    status);
2125 		}
2126 	}
2127 	return;
2128 }
2129 
2130 /*****************************************************************************
2131  * mos7840_get_lsr_info - get line status register info
2132  *
2133  * Purpose: Let user call ioctl() to get info when the UART physically
2134  * 	    is emptied.  On bus types like RS485, the transmitter must
2135  * 	    release the bus after transmitting. This must be done when
2136  * 	    the transmit shift register is empty, not be done when the
2137  * 	    transmit holding register is empty.  This functionality
2138  * 	    allows an RS485 driver to be written in user space.
2139  *****************************************************************************/
2140 
2141 static int mos7840_get_lsr_info(struct tty_struct *tty,
2142 				unsigned int __user *value)
2143 {
2144 	int count;
2145 	unsigned int result = 0;
2146 
2147 	count = mos7840_chars_in_buffer(tty);
2148 	if (count == 0) {
2149 		dbg("%s -- Empty", __func__);
2150 		result = TIOCSER_TEMT;
2151 	}
2152 
2153 	if (copy_to_user(value, &result, sizeof(int)))
2154 		return -EFAULT;
2155 	return 0;
2156 }
2157 
2158 /*****************************************************************************
2159  * mos7840_set_modem_info
2160  *      function to set modem info
2161  *****************************************************************************/
2162 
2163 /* FIXME: Should be using the model control hooks */
2164 
2165 static int mos7840_set_modem_info(struct moschip_port *mos7840_port,
2166 				  unsigned int cmd, unsigned int __user *value)
2167 {
2168 	unsigned int mcr;
2169 	unsigned int arg;
2170 	__u16 Data;
2171 	int status;
2172 	struct usb_serial_port *port;
2173 
2174 	if (mos7840_port == NULL)
2175 		return -1;
2176 
2177 	port = (struct usb_serial_port *)mos7840_port->port;
2178 	if (mos7840_port_paranoia_check(port, __func__)) {
2179 		dbg("%s", "Invalid port \n");
2180 		return -1;
2181 	}
2182 
2183 	mcr = mos7840_port->shadowMCR;
2184 
2185 	if (copy_from_user(&arg, value, sizeof(int)))
2186 		return -EFAULT;
2187 
2188 	switch (cmd) {
2189 	case TIOCMBIS:
2190 		if (arg & TIOCM_RTS)
2191 			mcr |= MCR_RTS;
2192 		if (arg & TIOCM_DTR)
2193 			mcr |= MCR_RTS;
2194 		if (arg & TIOCM_LOOP)
2195 			mcr |= MCR_LOOPBACK;
2196 		break;
2197 
2198 	case TIOCMBIC:
2199 		if (arg & TIOCM_RTS)
2200 			mcr &= ~MCR_RTS;
2201 		if (arg & TIOCM_DTR)
2202 			mcr &= ~MCR_RTS;
2203 		if (arg & TIOCM_LOOP)
2204 			mcr &= ~MCR_LOOPBACK;
2205 		break;
2206 
2207 	case TIOCMSET:
2208 		/* turn off the RTS and DTR and LOOPBACK
2209 		 * and then only turn on what was asked to */
2210 		mcr &= ~(MCR_RTS | MCR_DTR | MCR_LOOPBACK);
2211 		mcr |= ((arg & TIOCM_RTS) ? MCR_RTS : 0);
2212 		mcr |= ((arg & TIOCM_DTR) ? MCR_DTR : 0);
2213 		mcr |= ((arg & TIOCM_LOOP) ? MCR_LOOPBACK : 0);
2214 		break;
2215 	}
2216 
2217 	mos7840_port->shadowMCR = mcr;
2218 
2219 	Data = mos7840_port->shadowMCR;
2220 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2221 	if (status < 0) {
2222 		dbg("setting MODEM_CONTROL_REGISTER Failed\n");
2223 		return -1;
2224 	}
2225 
2226 	return 0;
2227 }
2228 
2229 /*****************************************************************************
2230  * mos7840_get_modem_info
2231  *      function to get modem info
2232  *****************************************************************************/
2233 
2234 static int mos7840_get_modem_info(struct moschip_port *mos7840_port,
2235 				  unsigned int __user *value)
2236 {
2237 	unsigned int result = 0;
2238 	__u16 msr;
2239 	unsigned int mcr = mos7840_port->shadowMCR;
2240         mos7840_get_uart_reg(mos7840_port->port,
2241 						MODEM_STATUS_REGISTER, &msr);
2242 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)	/* 0x002 */
2243 	    |((mcr & MCR_RTS) ? TIOCM_RTS : 0)	/* 0x004 */
2244 	    |((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)	/* 0x020 */
2245 	    |((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)	/* 0x040 */
2246 	    |((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)	/* 0x080 */
2247 	    |((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);	/* 0x100 */
2248 
2249 	dbg("%s -- %x", __func__, result);
2250 
2251 	if (copy_to_user(value, &result, sizeof(int)))
2252 		return -EFAULT;
2253 	return 0;
2254 }
2255 
2256 /*****************************************************************************
2257  * mos7840_get_serial_info
2258  *      function to get information about serial port
2259  *****************************************************************************/
2260 
2261 static int mos7840_get_serial_info(struct moschip_port *mos7840_port,
2262 				   struct serial_struct __user *retinfo)
2263 {
2264 	struct serial_struct tmp;
2265 
2266 	if (mos7840_port == NULL)
2267 		return -1;
2268 
2269 	if (!retinfo)
2270 		return -EFAULT;
2271 
2272 	memset(&tmp, 0, sizeof(tmp));
2273 
2274 	tmp.type = PORT_16550A;
2275 	tmp.line = mos7840_port->port->serial->minor;
2276 	tmp.port = mos7840_port->port->number;
2277 	tmp.irq = 0;
2278 	tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
2279 	tmp.xmit_fifo_size = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
2280 	tmp.baud_base = 9600;
2281 	tmp.close_delay = 5 * HZ;
2282 	tmp.closing_wait = 30 * HZ;
2283 
2284 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
2285 		return -EFAULT;
2286 	return 0;
2287 }
2288 
2289 /*****************************************************************************
2290  * SerialIoctl
2291  *	this function handles any ioctl calls to the driver
2292  *****************************************************************************/
2293 
2294 static int mos7840_ioctl(struct tty_struct *tty, struct file *file,
2295 			 unsigned int cmd, unsigned long arg)
2296 {
2297 	struct usb_serial_port *port = tty->driver_data;
2298 	void __user *argp = (void __user *)arg;
2299 	struct moschip_port *mos7840_port;
2300 
2301 	struct async_icount cnow;
2302 	struct async_icount cprev;
2303 	struct serial_icounter_struct icount;
2304 	int mosret = 0;
2305 
2306 	if (mos7840_port_paranoia_check(port, __func__)) {
2307 		dbg("%s", "Invalid port \n");
2308 		return -1;
2309 	}
2310 
2311 	mos7840_port = mos7840_get_port_private(port);
2312 
2313 	if (mos7840_port == NULL)
2314 		return -1;
2315 
2316 	dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
2317 
2318 	switch (cmd) {
2319 		/* return number of bytes available */
2320 
2321 	case TIOCSERGETLSR:
2322 		dbg("%s (%d) TIOCSERGETLSR", __func__, port->number);
2323 		return mos7840_get_lsr_info(tty, argp);
2324 		return 0;
2325 
2326 	/* FIXME: use the modem hooks and remove this */
2327 	case TIOCMBIS:
2328 	case TIOCMBIC:
2329 	case TIOCMSET:
2330 		dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET", __func__,
2331 		    port->number);
2332 		mosret =
2333 		    mos7840_set_modem_info(mos7840_port, cmd, argp);
2334 		return mosret;
2335 
2336 	case TIOCMGET:
2337 		dbg("%s (%d) TIOCMGET", __func__, port->number);
2338 		return mos7840_get_modem_info(mos7840_port, argp);
2339 
2340 	case TIOCGSERIAL:
2341 		dbg("%s (%d) TIOCGSERIAL", __func__, port->number);
2342 		return mos7840_get_serial_info(mos7840_port, argp);
2343 
2344 	case TIOCSSERIAL:
2345 		dbg("%s (%d) TIOCSSERIAL", __func__, port->number);
2346 		break;
2347 
2348 	case TIOCMIWAIT:
2349 		dbg("%s (%d) TIOCMIWAIT", __func__, port->number);
2350 		cprev = mos7840_port->icount;
2351 		while (1) {
2352 			/* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */
2353 			mos7840_port->delta_msr_cond = 0;
2354 			wait_event_interruptible(mos7840_port->delta_msr_wait,
2355 						 (mos7840_port->
2356 						  delta_msr_cond == 1));
2357 
2358 			/* see if a signal did it */
2359 			if (signal_pending(current))
2360 				return -ERESTARTSYS;
2361 			cnow = mos7840_port->icount;
2362 			smp_rmb();
2363 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2364 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
2365 				return -EIO;	/* no change => error */
2366 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
2367 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
2368 			    ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
2369 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
2370 				return 0;
2371 			}
2372 			cprev = cnow;
2373 		}
2374 		/* NOTREACHED */
2375 		break;
2376 
2377 	case TIOCGICOUNT:
2378 		cnow = mos7840_port->icount;
2379 		smp_rmb();
2380 		icount.cts = cnow.cts;
2381 		icount.dsr = cnow.dsr;
2382 		icount.rng = cnow.rng;
2383 		icount.dcd = cnow.dcd;
2384 		icount.rx = cnow.rx;
2385 		icount.tx = cnow.tx;
2386 		icount.frame = cnow.frame;
2387 		icount.overrun = cnow.overrun;
2388 		icount.parity = cnow.parity;
2389 		icount.brk = cnow.brk;
2390 		icount.buf_overrun = cnow.buf_overrun;
2391 
2392 		dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
2393 		    port->number, icount.rx, icount.tx);
2394 		if (copy_to_user(argp, &icount, sizeof(icount)))
2395 			return -EFAULT;
2396 		return 0;
2397 	default:
2398 		break;
2399 	}
2400 	return -ENOIOCTLCMD;
2401 }
2402 
2403 static int mos7840_calc_num_ports(struct usb_serial *serial)
2404 {
2405 	int mos7840_num_ports = 0;
2406 
2407 	dbg("numberofendpoints: %d \n",
2408 	    (int)serial->interface->cur_altsetting->desc.bNumEndpoints);
2409 	dbg("numberofendpoints: %d \n",
2410 	    (int)serial->interface->altsetting->desc.bNumEndpoints);
2411 	if (serial->interface->cur_altsetting->desc.bNumEndpoints == 5) {
2412 		mos7840_num_ports = serial->num_ports = 2;
2413 	} else if (serial->interface->cur_altsetting->desc.bNumEndpoints == 9) {
2414 		serial->num_bulk_in = 4;
2415 		serial->num_bulk_out = 4;
2416 		mos7840_num_ports = serial->num_ports = 4;
2417 	}
2418 
2419 	return mos7840_num_ports;
2420 }
2421 
2422 /****************************************************************************
2423  * mos7840_startup
2424  ****************************************************************************/
2425 
2426 static int mos7840_startup(struct usb_serial *serial)
2427 {
2428 	struct moschip_port *mos7840_port;
2429 	struct usb_device *dev;
2430 	int i, status;
2431 
2432 	__u16 Data;
2433 	dbg("%s \n", " mos7840_startup :entering..........");
2434 
2435 	if (!serial) {
2436 		dbg("%s\n", "Invalid Handler");
2437 		return -1;
2438 	}
2439 
2440 	dev = serial->dev;
2441 
2442 	dbg("%s\n", "Entering...");
2443 
2444 	/* we set up the pointers to the endpoints in the mos7840_open *
2445 	 * function, as the structures aren't created yet.             */
2446 
2447 	/* set up port private structures */
2448 	for (i = 0; i < serial->num_ports; ++i) {
2449 		mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2450 		if (mos7840_port == NULL) {
2451 			dev_err(&dev->dev, "%s - Out of memory\n", __func__);
2452 			status = -ENOMEM;
2453 			i--; /* don't follow NULL pointer cleaning up */
2454 			goto error;
2455 		}
2456 
2457 		/* Initialize all port interrupt end point to port 0 int
2458 		 * endpoint. Our device has only one interrupt end point
2459 		 * common to all port */
2460 
2461 		mos7840_port->port = serial->port[i];
2462 		mos7840_set_port_private(serial->port[i], mos7840_port);
2463 		spin_lock_init(&mos7840_port->pool_lock);
2464 
2465 		mos7840_port->port_num = ((serial->port[i]->number -
2466 					   (serial->port[i]->serial->minor)) +
2467 					  1);
2468 
2469 		if (mos7840_port->port_num == 1) {
2470 			mos7840_port->SpRegOffset = 0x0;
2471 			mos7840_port->ControlRegOffset = 0x1;
2472 			mos7840_port->DcrRegOffset = 0x4;
2473 		} else if ((mos7840_port->port_num == 2)
2474 			   && (serial->num_ports == 4)) {
2475 			mos7840_port->SpRegOffset = 0x8;
2476 			mos7840_port->ControlRegOffset = 0x9;
2477 			mos7840_port->DcrRegOffset = 0x16;
2478 		} else if ((mos7840_port->port_num == 2)
2479 			   && (serial->num_ports == 2)) {
2480 			mos7840_port->SpRegOffset = 0xa;
2481 			mos7840_port->ControlRegOffset = 0xb;
2482 			mos7840_port->DcrRegOffset = 0x19;
2483 		} else if ((mos7840_port->port_num == 3)
2484 			   && (serial->num_ports == 4)) {
2485 			mos7840_port->SpRegOffset = 0xa;
2486 			mos7840_port->ControlRegOffset = 0xb;
2487 			mos7840_port->DcrRegOffset = 0x19;
2488 		} else if ((mos7840_port->port_num == 4)
2489 			   && (serial->num_ports == 4)) {
2490 			mos7840_port->SpRegOffset = 0xc;
2491 			mos7840_port->ControlRegOffset = 0xd;
2492 			mos7840_port->DcrRegOffset = 0x1c;
2493 		}
2494 		mos7840_dump_serial_port(mos7840_port);
2495 		mos7840_set_port_private(serial->port[i], mos7840_port);
2496 
2497 		/* enable rx_disable bit in control register */
2498 		status = mos7840_get_reg_sync(serial->port[i],
2499 				 mos7840_port->ControlRegOffset, &Data);
2500 		if (status < 0) {
2501 			dbg("Reading ControlReg failed status-0x%x\n", status);
2502 			break;
2503 		} else
2504 			dbg("ControlReg Reading success val is %x, status%d\n",
2505 			    Data, status);
2506 		Data |= 0x08;	/* setting driver done bit */
2507 		Data |= 0x04;	/* sp1_bit to have cts change reflect in
2508 				   modem status reg */
2509 
2510 		/* Data |= 0x20; //rx_disable bit */
2511 		status = mos7840_set_reg_sync(serial->port[i],
2512 					 mos7840_port->ControlRegOffset, Data);
2513 		if (status < 0) {
2514 			dbg("Writing ControlReg failed(rx_disable) status-0x%x\n", status);
2515 			break;
2516 		} else
2517 			dbg("ControlReg Writing success(rx_disable) status%d\n",
2518 			    status);
2519 
2520 		/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
2521 		   and 0x24 in DCR3 */
2522 		Data = 0x01;
2523 		status = mos7840_set_reg_sync(serial->port[i],
2524 			 (__u16) (mos7840_port->DcrRegOffset + 0), Data);
2525 		if (status < 0) {
2526 			dbg("Writing DCR0 failed status-0x%x\n", status);
2527 			break;
2528 		} else
2529 			dbg("DCR0 Writing success status%d\n", status);
2530 
2531 		Data = 0x05;
2532 		status = mos7840_set_reg_sync(serial->port[i],
2533 			 (__u16) (mos7840_port->DcrRegOffset + 1), Data);
2534 		if (status < 0) {
2535 			dbg("Writing DCR1 failed status-0x%x\n", status);
2536 			break;
2537 		} else
2538 			dbg("DCR1 Writing success status%d\n", status);
2539 
2540 		Data = 0x24;
2541 		status = mos7840_set_reg_sync(serial->port[i],
2542 			 (__u16) (mos7840_port->DcrRegOffset + 2), Data);
2543 		if (status < 0) {
2544 			dbg("Writing DCR2 failed status-0x%x\n", status);
2545 			break;
2546 		} else
2547 			dbg("DCR2 Writing success status%d\n", status);
2548 
2549 		/* write values in clkstart0x0 and clkmulti 0x20 */
2550 		Data = 0x0;
2551 		status = mos7840_set_reg_sync(serial->port[i],
2552 					 CLK_START_VALUE_REGISTER, Data);
2553 		if (status < 0) {
2554 			dbg("Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
2555 			break;
2556 		} else
2557 			dbg("CLK_START_VALUE_REGISTER Writing success status%d\n", status);
2558 
2559 		Data = 0x20;
2560 		status = mos7840_set_reg_sync(serial->port[i],
2561 					CLK_MULTI_REGISTER, Data);
2562 		if (status < 0) {
2563 			dbg("Writing CLK_MULTI_REGISTER failed status-0x%x\n",
2564 			    status);
2565 			goto error;
2566 		} else
2567 			dbg("CLK_MULTI_REGISTER Writing success status%d\n",
2568 			    status);
2569 
2570 		/* write value 0x0 to scratchpad register */
2571 		Data = 0x00;
2572 		status = mos7840_set_uart_reg(serial->port[i],
2573 						SCRATCH_PAD_REGISTER, Data);
2574 		if (status < 0) {
2575 			dbg("Writing SCRATCH_PAD_REGISTER failed status-0x%x\n",
2576 			    status);
2577 			break;
2578 		} else
2579 			dbg("SCRATCH_PAD_REGISTER Writing success status%d\n",
2580 			    status);
2581 
2582 		/* Zero Length flag register */
2583 		if ((mos7840_port->port_num != 1)
2584 		    && (serial->num_ports == 2)) {
2585 
2586 			Data = 0xff;
2587 			status = mos7840_set_reg_sync(serial->port[i],
2588 				      (__u16) (ZLP_REG1 +
2589 				      ((__u16)mos7840_port->port_num)), Data);
2590 			dbg("ZLIP offset%x\n",
2591 			    (__u16) (ZLP_REG1 +
2592 					((__u16) mos7840_port->port_num)));
2593 			if (status < 0) {
2594 				dbg("Writing ZLP_REG%d failed status-0x%x\n",
2595 				    i + 2, status);
2596 				break;
2597 			} else
2598 				dbg("ZLP_REG%d Writing success status%d\n",
2599 				    i + 2, status);
2600 		} else {
2601 			Data = 0xff;
2602 			status = mos7840_set_reg_sync(serial->port[i],
2603 			      (__u16) (ZLP_REG1 +
2604 			      ((__u16)mos7840_port->port_num) - 0x1), Data);
2605 			dbg("ZLIP offset%x\n",
2606 			    (__u16) (ZLP_REG1 +
2607 				     ((__u16) mos7840_port->port_num) - 0x1));
2608 			if (status < 0) {
2609 				dbg("Writing ZLP_REG%d failed status-0x%x\n",
2610 				    i + 1, status);
2611 				break;
2612 			} else
2613 				dbg("ZLP_REG%d Writing success status%d\n",
2614 				    i + 1, status);
2615 
2616 		}
2617 		mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
2618 		mos7840_port->ctrl_buf = kmalloc(16, GFP_KERNEL);
2619 		mos7840_port->dr = kmalloc(sizeof(struct usb_ctrlrequest),
2620 								GFP_KERNEL);
2621 		if (!mos7840_port->control_urb || !mos7840_port->ctrl_buf ||
2622 							!mos7840_port->dr) {
2623 			status = -ENOMEM;
2624 			goto error;
2625 		}
2626 	}
2627 
2628 	/* Zero Length flag enable */
2629 	Data = 0x0f;
2630 	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
2631 	if (status < 0) {
2632 		dbg("Writing ZLP_REG5 failed status-0x%x\n", status);
2633 		goto error;
2634 	} else
2635 		dbg("ZLP_REG5 Writing success status%d\n", status);
2636 
2637 	/* setting configuration feature to one */
2638 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2639 			(__u8) 0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5 * HZ);
2640 	return 0;
2641 error:
2642 	for (/* nothing */; i >= 0; i--) {
2643 		mos7840_port = mos7840_get_port_private(serial->port[i]);
2644 
2645 		kfree(mos7840_port->dr);
2646 		kfree(mos7840_port->ctrl_buf);
2647 		usb_free_urb(mos7840_port->control_urb);
2648 		kfree(mos7840_port);
2649 		serial->port[i] = NULL;
2650 	}
2651 	return status;
2652 }
2653 
2654 /****************************************************************************
2655  * mos7840_shutdown
2656  *	This function is called whenever the device is removed from the usb bus.
2657  ****************************************************************************/
2658 
2659 static void mos7840_shutdown(struct usb_serial *serial)
2660 {
2661 	int i;
2662 	unsigned long flags;
2663 	struct moschip_port *mos7840_port;
2664 	dbg("%s \n", " shutdown :entering..........");
2665 
2666 	if (!serial) {
2667 		dbg("%s", "Invalid Handler \n");
2668 		return;
2669 	}
2670 
2671 	/* check for the ports to be closed,close the ports and disconnect */
2672 
2673 	/* free private structure allocated for serial port  *
2674 	 * stop reads and writes on all ports                */
2675 
2676 	for (i = 0; i < serial->num_ports; ++i) {
2677 		mos7840_port = mos7840_get_port_private(serial->port[i]);
2678 		spin_lock_irqsave(&mos7840_port->pool_lock, flags);
2679 		mos7840_port->zombie = 1;
2680 		spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
2681 		usb_kill_urb(mos7840_port->control_urb);
2682 		kfree(mos7840_port->ctrl_buf);
2683 		kfree(mos7840_port->dr);
2684 		kfree(mos7840_port);
2685 		mos7840_set_port_private(serial->port[i], NULL);
2686 	}
2687 
2688 	dbg("%s\n", "Thank u :: ");
2689 
2690 }
2691 
2692 static struct usb_driver io_driver = {
2693 	.name = "mos7840",
2694 	.probe = usb_serial_probe,
2695 	.disconnect = usb_serial_disconnect,
2696 	.id_table = moschip_id_table_combined,
2697 	.no_dynamic_id = 1,
2698 };
2699 
2700 static struct usb_serial_driver moschip7840_4port_device = {
2701 	.driver = {
2702 		   .owner = THIS_MODULE,
2703 		   .name = "mos7840",
2704 		   },
2705 	.description = DRIVER_DESC,
2706 	.usb_driver = &io_driver,
2707 	.id_table = moschip_port_id_table,
2708 	.num_ports = 4,
2709 	.open = mos7840_open,
2710 	.close = mos7840_close,
2711 	.write = mos7840_write,
2712 	.write_room = mos7840_write_room,
2713 	.chars_in_buffer = mos7840_chars_in_buffer,
2714 	.throttle = mos7840_throttle,
2715 	.unthrottle = mos7840_unthrottle,
2716 	.calc_num_ports = mos7840_calc_num_ports,
2717 #ifdef MCSSerialProbe
2718 	.probe = mos7840_serial_probe,
2719 #endif
2720 	.ioctl = mos7840_ioctl,
2721 	.set_termios = mos7840_set_termios,
2722 	.break_ctl = mos7840_break,
2723 	.tiocmget = mos7840_tiocmget,
2724 	.tiocmset = mos7840_tiocmset,
2725 	.attach = mos7840_startup,
2726 	.shutdown = mos7840_shutdown,
2727 	.read_bulk_callback = mos7840_bulk_in_callback,
2728 	.read_int_callback = mos7840_interrupt_callback,
2729 };
2730 
2731 /****************************************************************************
2732  * moschip7840_init
2733  *	This is called by the module subsystem, or on startup to initialize us
2734  ****************************************************************************/
2735 static int __init moschip7840_init(void)
2736 {
2737 	int retval;
2738 
2739 	dbg("%s \n", " mos7840_init :entering..........");
2740 
2741 	/* Register with the usb serial */
2742 	retval = usb_serial_register(&moschip7840_4port_device);
2743 
2744 	if (retval)
2745 		goto failed_port_device_register;
2746 
2747 	dbg("%s\n", "Entring...");
2748 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
2749 	       DRIVER_DESC "\n");
2750 
2751 	/* Register with the usb */
2752 	retval = usb_register(&io_driver);
2753 	if (retval == 0) {
2754 		dbg("%s\n", "Leaving...");
2755 		return 0;
2756 	}
2757 	usb_serial_deregister(&moschip7840_4port_device);
2758 failed_port_device_register:
2759 	return retval;
2760 }
2761 
2762 /****************************************************************************
2763  * moschip7840_exit
2764  *	Called when the driver is about to be unloaded.
2765  ****************************************************************************/
2766 static void __exit moschip7840_exit(void)
2767 {
2768 
2769 	dbg("%s \n", " mos7840_exit :entering..........");
2770 
2771 	usb_deregister(&io_driver);
2772 
2773 	usb_serial_deregister(&moschip7840_4port_device);
2774 
2775 	dbg("%s\n", "Entring...");
2776 }
2777 
2778 module_init(moschip7840_init);
2779 module_exit(moschip7840_exit);
2780 
2781 /* Module information */
2782 MODULE_DESCRIPTION(DRIVER_DESC);
2783 MODULE_LICENSE("GPL");
2784 
2785 module_param(debug, bool, S_IRUGO | S_IWUSR);
2786 MODULE_PARM_DESC(debug, "Debug enabled or not");
2787