xref: /openbmc/linux/drivers/usb/serial/mos7840.c (revision 05bcf503)
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 "1.3.2"
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 MOS_WDR_TIMEOUT		5000	/* default urb timeout */
86 
87 #define MOS_PORT1       0x0200
88 #define MOS_PORT2       0x0300
89 #define MOS_VENREG      0x0000
90 #define MOS_MAX_PORT	0x02
91 #define MOS_WRITE       0x0E
92 #define MOS_READ        0x0D
93 
94 /* Requests */
95 #define MCS_RD_RTYPE    0xC0
96 #define MCS_WR_RTYPE    0x40
97 #define MCS_RDREQ       0x0D
98 #define MCS_WRREQ       0x0E
99 #define MCS_CTRL_TIMEOUT        500
100 #define VENDOR_READ_LENGTH      (0x01)
101 
102 #define MAX_NAME_LEN    64
103 
104 #define ZLP_REG1  0x3A		/* Zero_Flag_Reg1    58 */
105 #define ZLP_REG5  0x3E		/* Zero_Flag_Reg5    62 */
106 
107 /* For higher baud Rates use TIOCEXBAUD */
108 #define TIOCEXBAUD     0x5462
109 
110 /* vendor id and device id defines */
111 
112 /* The native mos7840/7820 component */
113 #define USB_VENDOR_ID_MOSCHIP           0x9710
114 #define MOSCHIP_DEVICE_ID_7840          0x7840
115 #define MOSCHIP_DEVICE_ID_7820          0x7820
116 #define MOSCHIP_DEVICE_ID_7810          0x7810
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 id_table.
120  */
121 #define USB_VENDOR_ID_BANDB              0x0856
122 #define BANDB_DEVICE_ID_USO9ML2_2        0xAC22
123 #define BANDB_DEVICE_ID_USO9ML2_2P       0xBC00
124 #define BANDB_DEVICE_ID_USO9ML2_4        0xAC24
125 #define BANDB_DEVICE_ID_USO9ML2_4P       0xBC01
126 #define BANDB_DEVICE_ID_US9ML2_2         0xAC29
127 #define BANDB_DEVICE_ID_US9ML2_4         0xAC30
128 #define BANDB_DEVICE_ID_USPTL4_2         0xAC31
129 #define BANDB_DEVICE_ID_USPTL4_4         0xAC32
130 #define BANDB_DEVICE_ID_USOPTL4_2        0xAC42
131 #define BANDB_DEVICE_ID_USOPTL4_2P       0xBC02
132 #define BANDB_DEVICE_ID_USOPTL4_4        0xAC44
133 #define BANDB_DEVICE_ID_USOPTL4_4P       0xBC03
134 #define BANDB_DEVICE_ID_USOPTL2_4        0xAC24
135 
136 /* This driver also supports
137  * ATEN UC2324 device using Moschip MCS7840
138  * ATEN UC2322 device using Moschip MCS7820
139  */
140 #define USB_VENDOR_ID_ATENINTL		0x0557
141 #define ATENINTL_DEVICE_ID_UC2324	0x2011
142 #define ATENINTL_DEVICE_ID_UC2322	0x7820
143 
144 /* Interrupt Routine Defines    */
145 
146 #define SERIAL_IIR_RLS      0x06
147 #define SERIAL_IIR_MS       0x00
148 
149 /*
150  *  Emulation of the bit mask on the LINE STATUS REGISTER.
151  */
152 #define SERIAL_LSR_DR       0x0001
153 #define SERIAL_LSR_OE       0x0002
154 #define SERIAL_LSR_PE       0x0004
155 #define SERIAL_LSR_FE       0x0008
156 #define SERIAL_LSR_BI       0x0010
157 
158 #define MOS_MSR_DELTA_CTS   0x10
159 #define MOS_MSR_DELTA_DSR   0x20
160 #define MOS_MSR_DELTA_RI    0x40
161 #define MOS_MSR_DELTA_CD    0x80
162 
163 /* Serial Port register Address */
164 #define INTERRUPT_ENABLE_REGISTER  ((__u16)(0x01))
165 #define FIFO_CONTROL_REGISTER      ((__u16)(0x02))
166 #define LINE_CONTROL_REGISTER      ((__u16)(0x03))
167 #define MODEM_CONTROL_REGISTER     ((__u16)(0x04))
168 #define LINE_STATUS_REGISTER       ((__u16)(0x05))
169 #define MODEM_STATUS_REGISTER      ((__u16)(0x06))
170 #define SCRATCH_PAD_REGISTER       ((__u16)(0x07))
171 #define DIVISOR_LATCH_LSB          ((__u16)(0x00))
172 #define DIVISOR_LATCH_MSB          ((__u16)(0x01))
173 
174 #define CLK_MULTI_REGISTER         ((__u16)(0x02))
175 #define CLK_START_VALUE_REGISTER   ((__u16)(0x03))
176 #define GPIO_REGISTER              ((__u16)(0x07))
177 
178 #define SERIAL_LCR_DLAB            ((__u16)(0x0080))
179 
180 /*
181  * URB POOL related defines
182  */
183 #define NUM_URBS                        16	/* URB Count */
184 #define URB_TRANSFER_BUFFER_SIZE        32	/* URB Size  */
185 
186 /* LED on/off milliseconds*/
187 #define LED_ON_MS	500
188 #define LED_OFF_MS	500
189 
190 static int device_type;
191 
192 static const struct usb_device_id id_table[] = {
193 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
194 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
195 	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7810)},
196 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2)},
197 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P)},
198 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4)},
199 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P)},
200 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2)},
201 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4)},
202 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2)},
203 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4)},
204 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2)},
205 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P)},
206 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4)},
207 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P)},
208 	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL2_4)},
209 	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2324)},
210 	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2322)},
211 	{}			/* terminating entry */
212 };
213 MODULE_DEVICE_TABLE(usb, id_table);
214 
215 /* This structure holds all of the local port information */
216 
217 struct moschip_port {
218 	int port_num;		/*Actual port number in the device(1,2,etc) */
219 	struct urb *write_urb;	/* write URB for this port */
220 	struct urb *read_urb;	/* read URB for this port */
221 	__u8 shadowLCR;		/* last LCR value received */
222 	__u8 shadowMCR;		/* last MCR value received */
223 	char open;
224 	char open_ports;
225 	wait_queue_head_t wait_chase;	/* for handling sleeping while waiting for chase to finish */
226 	wait_queue_head_t delta_msr_wait;	/* for handling sleeping while waiting for msr change to happen */
227 	int delta_msr_cond;
228 	struct async_icount icount;
229 	struct usb_serial_port *port;	/* loop back to the owner of this object */
230 
231 	/* Offsets */
232 	__u8 SpRegOffset;
233 	__u8 ControlRegOffset;
234 	__u8 DcrRegOffset;
235 	/* for processing control URBS in interrupt context */
236 	struct urb *control_urb;
237 	struct usb_ctrlrequest *dr;
238 	char *ctrl_buf;
239 	int MsrLsr;
240 
241 	spinlock_t pool_lock;
242 	struct urb *write_urb_pool[NUM_URBS];
243 	char busy[NUM_URBS];
244 	bool read_urb_busy;
245 
246 	/* For device(s) with LED indicator */
247 	bool has_led;
248 	bool led_flag;
249 	struct timer_list led_timer1;	/* Timer for LED on */
250 	struct timer_list led_timer2;	/* Timer for LED off */
251 };
252 
253 /*
254  * mos7840_set_reg_sync
255  * 	To set the Control register by calling usb_fill_control_urb function
256  *	by passing usb_sndctrlpipe function as parameter.
257  */
258 
259 static int mos7840_set_reg_sync(struct usb_serial_port *port, __u16 reg,
260 				__u16 val)
261 {
262 	struct usb_device *dev = port->serial->dev;
263 	val = val & 0x00ff;
264 	dev_dbg(&port->dev, "mos7840_set_reg_sync offset is %x, value %x\n", reg, val);
265 
266 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
267 			       MCS_WR_RTYPE, val, reg, NULL, 0,
268 			       MOS_WDR_TIMEOUT);
269 }
270 
271 /*
272  * mos7840_get_reg_sync
273  * 	To set the Uart register by calling usb_fill_control_urb function by
274  *	passing usb_rcvctrlpipe function as parameter.
275  */
276 
277 static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg,
278 				__u16 *val)
279 {
280 	struct usb_device *dev = port->serial->dev;
281 	int ret = 0;
282 	u8 *buf;
283 
284 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
285 	if (!buf)
286 		return -ENOMEM;
287 
288 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
289 			      MCS_RD_RTYPE, 0, reg, buf, VENDOR_READ_LENGTH,
290 			      MOS_WDR_TIMEOUT);
291 	*val = buf[0];
292 	dev_dbg(&port->dev, "%s offset is %x, return val %x\n", __func__, reg, *val);
293 
294 	kfree(buf);
295 	return ret;
296 }
297 
298 /*
299  * mos7840_set_uart_reg
300  *	To set the Uart register by calling usb_fill_control_urb function by
301  *	passing usb_sndctrlpipe function as parameter.
302  */
303 
304 static int mos7840_set_uart_reg(struct usb_serial_port *port, __u16 reg,
305 				__u16 val)
306 {
307 
308 	struct usb_device *dev = port->serial->dev;
309 	val = val & 0x00ff;
310 	/* For the UART control registers, the application number need
311 	   to be Or'ed */
312 	if (port->serial->num_ports == 4) {
313 		val |= (((__u16) port->number -
314 				(__u16) (port->serial->minor)) + 1) << 8;
315 	} else {
316 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
317 			val |= (((__u16) port->number -
318 			      (__u16) (port->serial->minor)) + 1) << 8;
319 		} else {
320 			val |= (((__u16) port->number -
321 			      (__u16) (port->serial->minor)) + 2) << 8;
322 		}
323 	}
324 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, val);
325 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ,
326 			       MCS_WR_RTYPE, val, reg, NULL, 0,
327 			       MOS_WDR_TIMEOUT);
328 
329 }
330 
331 /*
332  * mos7840_get_uart_reg
333  *	To set the Control register by calling usb_fill_control_urb function
334  *	by passing usb_rcvctrlpipe function as parameter.
335  */
336 static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg,
337 				__u16 *val)
338 {
339 	struct usb_device *dev = port->serial->dev;
340 	int ret = 0;
341 	__u16 Wval;
342 	u8 *buf;
343 
344 	buf = kmalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
345 	if (!buf)
346 		return -ENOMEM;
347 
348 	/* Wval  is same as application number */
349 	if (port->serial->num_ports == 4) {
350 		Wval =
351 		    (((__u16) port->number - (__u16) (port->serial->minor)) +
352 		     1) << 8;
353 	} else {
354 		if (((__u16) port->number - (__u16) (port->serial->minor)) == 0) {
355 			Wval = (((__u16) port->number -
356 			      (__u16) (port->serial->minor)) + 1) << 8;
357 		} else {
358 			Wval = (((__u16) port->number -
359 			      (__u16) (port->serial->minor)) + 2) << 8;
360 		}
361 	}
362 	dev_dbg(&port->dev, "%s application number is %x\n", __func__, Wval);
363 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ,
364 			      MCS_RD_RTYPE, Wval, reg, buf, VENDOR_READ_LENGTH,
365 			      MOS_WDR_TIMEOUT);
366 	*val = buf[0];
367 
368 	kfree(buf);
369 	return ret;
370 }
371 
372 static void mos7840_dump_serial_port(struct usb_serial_port *port,
373 				     struct moschip_port *mos7840_port)
374 {
375 
376 	dev_dbg(&port->dev, "SpRegOffset is %2x\n", mos7840_port->SpRegOffset);
377 	dev_dbg(&port->dev, "ControlRegOffset is %2x\n", mos7840_port->ControlRegOffset);
378 	dev_dbg(&port->dev, "DCRRegOffset is %2x\n", mos7840_port->DcrRegOffset);
379 
380 }
381 
382 /************************************************************************/
383 /************************************************************************/
384 /*             I N T E R F A C E   F U N C T I O N S			*/
385 /*             I N T E R F A C E   F U N C T I O N S			*/
386 /************************************************************************/
387 /************************************************************************/
388 
389 static inline void mos7840_set_port_private(struct usb_serial_port *port,
390 					    struct moschip_port *data)
391 {
392 	usb_set_serial_port_data(port, (void *)data);
393 }
394 
395 static inline struct moschip_port *mos7840_get_port_private(struct
396 							    usb_serial_port
397 							    *port)
398 {
399 	return (struct moschip_port *)usb_get_serial_port_data(port);
400 }
401 
402 static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
403 {
404 	struct moschip_port *mos7840_port;
405 	struct async_icount *icount;
406 	mos7840_port = port;
407 	icount = &mos7840_port->icount;
408 	if (new_msr &
409 	    (MOS_MSR_DELTA_CTS | MOS_MSR_DELTA_DSR | MOS_MSR_DELTA_RI |
410 	     MOS_MSR_DELTA_CD)) {
411 		icount = &mos7840_port->icount;
412 
413 		/* update input line counters */
414 		if (new_msr & MOS_MSR_DELTA_CTS) {
415 			icount->cts++;
416 			smp_wmb();
417 		}
418 		if (new_msr & MOS_MSR_DELTA_DSR) {
419 			icount->dsr++;
420 			smp_wmb();
421 		}
422 		if (new_msr & MOS_MSR_DELTA_CD) {
423 			icount->dcd++;
424 			smp_wmb();
425 		}
426 		if (new_msr & MOS_MSR_DELTA_RI) {
427 			icount->rng++;
428 			smp_wmb();
429 		}
430 	}
431 }
432 
433 static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)
434 {
435 	struct async_icount *icount;
436 
437 	if (new_lsr & SERIAL_LSR_BI) {
438 		/*
439 		 * Parity and Framing errors only count if they
440 		 * occur exclusive of a break being
441 		 * received.
442 		 */
443 		new_lsr &= (__u8) (SERIAL_LSR_OE | SERIAL_LSR_BI);
444 	}
445 
446 	/* update input line counters */
447 	icount = &port->icount;
448 	if (new_lsr & SERIAL_LSR_BI) {
449 		icount->brk++;
450 		smp_wmb();
451 	}
452 	if (new_lsr & SERIAL_LSR_OE) {
453 		icount->overrun++;
454 		smp_wmb();
455 	}
456 	if (new_lsr & SERIAL_LSR_PE) {
457 		icount->parity++;
458 		smp_wmb();
459 	}
460 	if (new_lsr & SERIAL_LSR_FE) {
461 		icount->frame++;
462 		smp_wmb();
463 	}
464 }
465 
466 /************************************************************************/
467 /************************************************************************/
468 /*            U S B  C A L L B A C K   F U N C T I O N S                */
469 /*            U S B  C A L L B A C K   F U N C T I O N S                */
470 /************************************************************************/
471 /************************************************************************/
472 
473 static void mos7840_control_callback(struct urb *urb)
474 {
475 	unsigned char *data;
476 	struct moschip_port *mos7840_port;
477 	struct device *dev = &urb->dev->dev;
478 	__u8 regval = 0x0;
479 	int status = urb->status;
480 
481 	mos7840_port = urb->context;
482 
483 	switch (status) {
484 	case 0:
485 		/* success */
486 		break;
487 	case -ECONNRESET:
488 	case -ENOENT:
489 	case -ESHUTDOWN:
490 		/* this urb is terminated, clean up */
491 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
492 		return;
493 	default:
494 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
495 		return;
496 	}
497 
498 	dev_dbg(dev, "%s urb buffer size is %d\n", __func__, urb->actual_length);
499 	dev_dbg(dev, "%s mos7840_port->MsrLsr is %d port %d\n", __func__,
500 		mos7840_port->MsrLsr, mos7840_port->port_num);
501 	data = urb->transfer_buffer;
502 	regval = (__u8) data[0];
503 	dev_dbg(dev, "%s data is %x\n", __func__, regval);
504 	if (mos7840_port->MsrLsr == 0)
505 		mos7840_handle_new_msr(mos7840_port, regval);
506 	else if (mos7840_port->MsrLsr == 1)
507 		mos7840_handle_new_lsr(mos7840_port, regval);
508 }
509 
510 static int mos7840_get_reg(struct moschip_port *mcs, __u16 Wval, __u16 reg,
511 			   __u16 *val)
512 {
513 	struct usb_device *dev = mcs->port->serial->dev;
514 	struct usb_ctrlrequest *dr = mcs->dr;
515 	unsigned char *buffer = mcs->ctrl_buf;
516 	int ret;
517 
518 	dr->bRequestType = MCS_RD_RTYPE;
519 	dr->bRequest = MCS_RDREQ;
520 	dr->wValue = cpu_to_le16(Wval);	/* 0 */
521 	dr->wIndex = cpu_to_le16(reg);
522 	dr->wLength = cpu_to_le16(2);
523 
524 	usb_fill_control_urb(mcs->control_urb, dev, usb_rcvctrlpipe(dev, 0),
525 			     (unsigned char *)dr, buffer, 2,
526 			     mos7840_control_callback, mcs);
527 	mcs->control_urb->transfer_buffer_length = 2;
528 	ret = usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
529 	return ret;
530 }
531 
532 static void mos7840_set_led_callback(struct urb *urb)
533 {
534 	switch (urb->status) {
535 	case 0:
536 		/* Success */
537 		break;
538 	case -ECONNRESET:
539 	case -ENOENT:
540 	case -ESHUTDOWN:
541 		/* This urb is terminated, clean up */
542 		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d",
543 			__func__, urb->status);
544 		break;
545 	default:
546 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d",
547 			__func__, urb->status);
548 	}
549 }
550 
551 static void mos7840_set_led_async(struct moschip_port *mcs, __u16 wval,
552 				__u16 reg)
553 {
554 	struct usb_device *dev = mcs->port->serial->dev;
555 	struct usb_ctrlrequest *dr = mcs->dr;
556 
557 	dr->bRequestType = MCS_WR_RTYPE;
558 	dr->bRequest = MCS_WRREQ;
559 	dr->wValue = cpu_to_le16(wval);
560 	dr->wIndex = cpu_to_le16(reg);
561 	dr->wLength = cpu_to_le16(0);
562 
563 	usb_fill_control_urb(mcs->control_urb, dev, usb_sndctrlpipe(dev, 0),
564 		(unsigned char *)dr, NULL, 0, mos7840_set_led_callback, NULL);
565 
566 	usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
567 }
568 
569 static void mos7840_set_led_sync(struct usb_serial_port *port, __u16 reg,
570 				__u16 val)
571 {
572 	struct usb_device *dev = port->serial->dev;
573 
574 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0), MCS_WRREQ, MCS_WR_RTYPE,
575 			val, reg, NULL, 0, MOS_WDR_TIMEOUT);
576 }
577 
578 static void mos7840_led_off(unsigned long arg)
579 {
580 	struct moschip_port *mcs = (struct moschip_port *) arg;
581 
582 	/* Turn off LED */
583 	mos7840_set_led_async(mcs, 0x0300, MODEM_CONTROL_REGISTER);
584 	mod_timer(&mcs->led_timer2,
585 				jiffies + msecs_to_jiffies(LED_OFF_MS));
586 }
587 
588 static void mos7840_led_flag_off(unsigned long arg)
589 {
590 	struct moschip_port *mcs = (struct moschip_port *) arg;
591 
592 	mcs->led_flag = false;
593 }
594 
595 /*****************************************************************************
596  * mos7840_interrupt_callback
597  *	this is the callback function for when we have received data on the
598  *	interrupt endpoint.
599  *****************************************************************************/
600 
601 static void mos7840_interrupt_callback(struct urb *urb)
602 {
603 	int result;
604 	int length;
605 	struct moschip_port *mos7840_port;
606 	struct usb_serial *serial;
607 	__u16 Data;
608 	unsigned char *data;
609 	__u8 sp[5], st;
610 	int i, rv = 0;
611 	__u16 wval, wreg = 0;
612 	int status = urb->status;
613 
614 	switch (status) {
615 	case 0:
616 		/* success */
617 		break;
618 	case -ECONNRESET:
619 	case -ENOENT:
620 	case -ESHUTDOWN:
621 		/* this urb is terminated, clean up */
622 		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
623 			__func__, status);
624 		return;
625 	default:
626 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
627 			__func__, status);
628 		goto exit;
629 	}
630 
631 	length = urb->actual_length;
632 	data = urb->transfer_buffer;
633 
634 	serial = urb->context;
635 
636 	/* Moschip get 5 bytes
637 	 * Byte 1 IIR Port 1 (port.number is 0)
638 	 * Byte 2 IIR Port 2 (port.number is 1)
639 	 * Byte 3 IIR Port 3 (port.number is 2)
640 	 * Byte 4 IIR Port 4 (port.number is 3)
641 	 * Byte 5 FIFO status for both */
642 
643 	if (length && length > 5) {
644 		dev_dbg(&urb->dev->dev, "%s", "Wrong data !!!\n");
645 		return;
646 	}
647 
648 	sp[0] = (__u8) data[0];
649 	sp[1] = (__u8) data[1];
650 	sp[2] = (__u8) data[2];
651 	sp[3] = (__u8) data[3];
652 	st = (__u8) data[4];
653 
654 	for (i = 0; i < serial->num_ports; i++) {
655 		mos7840_port = mos7840_get_port_private(serial->port[i]);
656 		wval =
657 		    (((__u16) serial->port[i]->number -
658 		      (__u16) (serial->minor)) + 1) << 8;
659 		if (mos7840_port->open) {
660 			if (sp[i] & 0x01) {
661 				dev_dbg(&urb->dev->dev, "SP%d No Interrupt !!!\n", i);
662 			} else {
663 				switch (sp[i] & 0x0f) {
664 				case SERIAL_IIR_RLS:
665 					dev_dbg(&urb->dev->dev, "Serial Port %d: Receiver status error or \n", i);
666 					dev_dbg(&urb->dev->dev, "address bit detected in 9-bit mode\n");
667 					mos7840_port->MsrLsr = 1;
668 					wreg = LINE_STATUS_REGISTER;
669 					break;
670 				case SERIAL_IIR_MS:
671 					dev_dbg(&urb->dev->dev, "Serial Port %d: Modem status change\n", i);
672 					mos7840_port->MsrLsr = 0;
673 					wreg = MODEM_STATUS_REGISTER;
674 					break;
675 				}
676 				rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
677 			}
678 		}
679 	}
680 	if (!(rv < 0))
681 		/* the completion handler for the control urb will resubmit */
682 		return;
683 exit:
684 	result = usb_submit_urb(urb, GFP_ATOMIC);
685 	if (result) {
686 		dev_err(&urb->dev->dev,
687 			"%s - Error %d submitting interrupt urb\n",
688 			__func__, result);
689 	}
690 }
691 
692 static int mos7840_port_paranoia_check(struct usb_serial_port *port,
693 				       const char *function)
694 {
695 	if (!port) {
696 		pr_debug("%s - port == NULL\n", function);
697 		return -1;
698 	}
699 	if (!port->serial) {
700 		pr_debug("%s - port->serial == NULL\n", function);
701 		return -1;
702 	}
703 
704 	return 0;
705 }
706 
707 /* Inline functions to check the sanity of a pointer that is passed to us */
708 static int mos7840_serial_paranoia_check(struct usb_serial *serial,
709 					 const char *function)
710 {
711 	if (!serial) {
712 		pr_debug("%s - serial == NULL\n", function);
713 		return -1;
714 	}
715 	if (!serial->type) {
716 		pr_debug("%s - serial->type == NULL!\n", function);
717 		return -1;
718 	}
719 
720 	return 0;
721 }
722 
723 static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
724 						 const char *function)
725 {
726 	/* if no port was specified, or it fails a paranoia check */
727 	if (!port ||
728 	    mos7840_port_paranoia_check(port, function) ||
729 	    mos7840_serial_paranoia_check(port->serial, function)) {
730 		/* then say that we don't have a valid usb_serial thing,
731 		 * which will end up genrating -ENODEV return values */
732 		return NULL;
733 	}
734 
735 	return port->serial;
736 }
737 
738 /*****************************************************************************
739  * mos7840_bulk_in_callback
740  *	this is the callback function for when we have received data on the
741  *	bulk in endpoint.
742  *****************************************************************************/
743 
744 static void mos7840_bulk_in_callback(struct urb *urb)
745 {
746 	int retval;
747 	unsigned char *data;
748 	struct usb_serial *serial;
749 	struct usb_serial_port *port;
750 	struct moschip_port *mos7840_port;
751 	struct tty_struct *tty;
752 	int status = urb->status;
753 
754 	mos7840_port = urb->context;
755 	if (!mos7840_port)
756 		return;
757 
758 	if (status) {
759 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
760 		mos7840_port->read_urb_busy = false;
761 		return;
762 	}
763 
764 	port = mos7840_port->port;
765 	if (mos7840_port_paranoia_check(port, __func__)) {
766 		mos7840_port->read_urb_busy = false;
767 		return;
768 	}
769 
770 	serial = mos7840_get_usb_serial(port, __func__);
771 	if (!serial) {
772 		mos7840_port->read_urb_busy = false;
773 		return;
774 	}
775 
776 	data = urb->transfer_buffer;
777 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
778 
779 	if (urb->actual_length) {
780 		tty = tty_port_tty_get(&mos7840_port->port->port);
781 		if (tty) {
782 			tty_insert_flip_string(tty, data, urb->actual_length);
783 			tty_flip_buffer_push(tty);
784 			tty_kref_put(tty);
785 		}
786 		mos7840_port->icount.rx += urb->actual_length;
787 		smp_wmb();
788 		dev_dbg(&port->dev, "mos7840_port->icount.rx is %d:\n", mos7840_port->icount.rx);
789 	}
790 
791 	if (!mos7840_port->read_urb) {
792 		dev_dbg(&port->dev, "%s", "URB KILLED !!!\n");
793 		mos7840_port->read_urb_busy = false;
794 		return;
795 	}
796 
797 	/* Turn on LED */
798 	if (mos7840_port->has_led && !mos7840_port->led_flag) {
799 		mos7840_port->led_flag = true;
800 		mos7840_set_led_async(mos7840_port, 0x0301,
801 					MODEM_CONTROL_REGISTER);
802 		mod_timer(&mos7840_port->led_timer1,
803 				jiffies + msecs_to_jiffies(LED_ON_MS));
804 	}
805 
806 	mos7840_port->read_urb_busy = true;
807 	retval = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
808 
809 	if (retval) {
810 		dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
811 		mos7840_port->read_urb_busy = false;
812 	}
813 }
814 
815 /*****************************************************************************
816  * mos7840_bulk_out_data_callback
817  *	this is the callback function for when we have finished sending
818  *	serial data on the bulk out endpoint.
819  *****************************************************************************/
820 
821 static void mos7840_bulk_out_data_callback(struct urb *urb)
822 {
823 	struct moschip_port *mos7840_port;
824 	struct usb_serial_port *port;
825 	struct tty_struct *tty;
826 	int status = urb->status;
827 	int i;
828 
829 	mos7840_port = urb->context;
830 	port = mos7840_port->port;
831 	spin_lock(&mos7840_port->pool_lock);
832 	for (i = 0; i < NUM_URBS; i++) {
833 		if (urb == mos7840_port->write_urb_pool[i]) {
834 			mos7840_port->busy[i] = 0;
835 			break;
836 		}
837 	}
838 	spin_unlock(&mos7840_port->pool_lock);
839 
840 	if (status) {
841 		dev_dbg(&port->dev, "nonzero write bulk status received:%d\n", status);
842 		return;
843 	}
844 
845 	if (mos7840_port_paranoia_check(port, __func__))
846 		return;
847 
848 	tty = tty_port_tty_get(&port->port);
849 	if (tty && mos7840_port->open)
850 		tty_wakeup(tty);
851 	tty_kref_put(tty);
852 
853 }
854 
855 /************************************************************************/
856 /*       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       */
857 /************************************************************************/
858 #ifdef MCSSerialProbe
859 static int mos7840_serial_probe(struct usb_serial *serial,
860 				const struct usb_device_id *id)
861 {
862 
863 	/*need to implement the mode_reg reading and updating\
864 	   structures usb_serial_ device_type\
865 	   (i.e num_ports, num_bulkin,bulkout etc) */
866 	/* Also we can update the changes  attach */
867 	return 1;
868 }
869 #endif
870 
871 /*****************************************************************************
872  * mos7840_open
873  *	this function is called by the tty driver when a port is opened
874  *	If successful, we return 0
875  *	Otherwise we return a negative error number.
876  *****************************************************************************/
877 
878 static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
879 {
880 	int response;
881 	int j;
882 	struct usb_serial *serial;
883 	struct urb *urb;
884 	__u16 Data;
885 	int status;
886 	struct moschip_port *mos7840_port;
887 	struct moschip_port *port0;
888 
889 	if (mos7840_port_paranoia_check(port, __func__))
890 		return -ENODEV;
891 
892 	serial = port->serial;
893 
894 	if (mos7840_serial_paranoia_check(serial, __func__))
895 		return -ENODEV;
896 
897 	mos7840_port = mos7840_get_port_private(port);
898 	port0 = mos7840_get_port_private(serial->port[0]);
899 
900 	if (mos7840_port == NULL || port0 == NULL)
901 		return -ENODEV;
902 
903 	usb_clear_halt(serial->dev, port->write_urb->pipe);
904 	usb_clear_halt(serial->dev, port->read_urb->pipe);
905 	port0->open_ports++;
906 
907 	/* Initialising the write urb pool */
908 	for (j = 0; j < NUM_URBS; ++j) {
909 		urb = usb_alloc_urb(0, GFP_KERNEL);
910 		mos7840_port->write_urb_pool[j] = urb;
911 
912 		if (urb == NULL) {
913 			dev_err(&port->dev, "No more urbs???\n");
914 			continue;
915 		}
916 
917 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
918 								GFP_KERNEL);
919 		if (!urb->transfer_buffer) {
920 			usb_free_urb(urb);
921 			mos7840_port->write_urb_pool[j] = NULL;
922 			dev_err(&port->dev,
923 				"%s-out of memory for urb buffers.\n",
924 				__func__);
925 			continue;
926 		}
927 	}
928 
929 /*****************************************************************************
930  * Initialize MCS7840 -- Write Init values to corresponding Registers
931  *
932  * Register Index
933  * 1 : IER
934  * 2 : FCR
935  * 3 : LCR
936  * 4 : MCR
937  *
938  * 0x08 : SP1/2 Control Reg
939  *****************************************************************************/
940 
941 	/* NEED to check the following Block */
942 
943 	Data = 0x0;
944 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
945 	if (status < 0) {
946 		dev_dbg(&port->dev, "Reading Spreg failed\n");
947 		return -1;
948 	}
949 	Data |= 0x80;
950 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
951 	if (status < 0) {
952 		dev_dbg(&port->dev, "writing Spreg failed\n");
953 		return -1;
954 	}
955 
956 	Data &= ~0x80;
957 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
958 	if (status < 0) {
959 		dev_dbg(&port->dev, "writing Spreg failed\n");
960 		return -1;
961 	}
962 	/* End of block to be checked */
963 
964 	Data = 0x0;
965 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
966 									&Data);
967 	if (status < 0) {
968 		dev_dbg(&port->dev, "Reading Controlreg failed\n");
969 		return -1;
970 	}
971 	Data |= 0x08;		/* Driver done bit */
972 	Data |= 0x20;		/* rx_disable */
973 	status = mos7840_set_reg_sync(port,
974 				mos7840_port->ControlRegOffset, Data);
975 	if (status < 0) {
976 		dev_dbg(&port->dev, "writing Controlreg failed\n");
977 		return -1;
978 	}
979 	/* do register settings here */
980 	/* Set all regs to the device default values. */
981 	/***********************************
982 	 * First Disable all interrupts.
983 	 ***********************************/
984 	Data = 0x00;
985 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
986 	if (status < 0) {
987 		dev_dbg(&port->dev, "disabling interrupts failed\n");
988 		return -1;
989 	}
990 	/* Set FIFO_CONTROL_REGISTER to the default value */
991 	Data = 0x00;
992 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
993 	if (status < 0) {
994 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
995 		return -1;
996 	}
997 
998 	Data = 0xcf;
999 	status = mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1000 	if (status < 0) {
1001 		dev_dbg(&port->dev, "Writing FIFO_CONTROL_REGISTER  failed\n");
1002 		return -1;
1003 	}
1004 
1005 	Data = 0x03;
1006 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1007 	mos7840_port->shadowLCR = Data;
1008 
1009 	Data = 0x0b;
1010 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1011 	mos7840_port->shadowMCR = Data;
1012 
1013 	Data = 0x00;
1014 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1015 	mos7840_port->shadowLCR = Data;
1016 
1017 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
1018 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1019 
1020 	Data = 0x0c;
1021 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1022 
1023 	Data = 0x0;
1024 	status = mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1025 
1026 	Data = 0x00;
1027 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1028 
1029 	Data = Data & ~SERIAL_LCR_DLAB;
1030 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1031 	mos7840_port->shadowLCR = Data;
1032 
1033 	/* clearing Bulkin and Bulkout Fifo */
1034 	Data = 0x0;
1035 	status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset, &Data);
1036 
1037 	Data = Data | 0x0c;
1038 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
1039 
1040 	Data = Data & ~0x0c;
1041 	status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
1042 	/* Finally enable all interrupts */
1043 	Data = 0x0c;
1044 	status = mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1045 
1046 	/* clearing rx_disable */
1047 	Data = 0x0;
1048 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
1049 									&Data);
1050 	Data = Data & ~0x20;
1051 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
1052 									Data);
1053 
1054 	/* rx_negate */
1055 	Data = 0x0;
1056 	status = mos7840_get_reg_sync(port, mos7840_port->ControlRegOffset,
1057 									&Data);
1058 	Data = Data | 0x10;
1059 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
1060 									Data);
1061 
1062 	/* Check to see if we've set up our endpoint info yet    *
1063 	 * (can't set it up in mos7840_startup as the structures *
1064 	 * were not set up at that time.)                        */
1065 	if (port0->open_ports == 1) {
1066 		if (serial->port[0]->interrupt_in_buffer == NULL) {
1067 			/* set up interrupt urb */
1068 			usb_fill_int_urb(serial->port[0]->interrupt_in_urb,
1069 				serial->dev,
1070 				usb_rcvintpipe(serial->dev,
1071 				serial->port[0]->interrupt_in_endpointAddress),
1072 				serial->port[0]->interrupt_in_buffer,
1073 				serial->port[0]->interrupt_in_urb->
1074 				transfer_buffer_length,
1075 				mos7840_interrupt_callback,
1076 				serial,
1077 				serial->port[0]->interrupt_in_urb->interval);
1078 
1079 			/* start interrupt read for mos7840               *
1080 			 * will continue as long as mos7840 is connected  */
1081 
1082 			response =
1083 			    usb_submit_urb(serial->port[0]->interrupt_in_urb,
1084 					   GFP_KERNEL);
1085 			if (response) {
1086 				dev_err(&port->dev, "%s - Error %d submitting "
1087 					"interrupt urb\n", __func__, response);
1088 			}
1089 
1090 		}
1091 
1092 	}
1093 
1094 	/* see if we've set up our endpoint info yet   *
1095 	 * (can't set it up in mos7840_startup as the  *
1096 	 * structures were not set up at that time.)   */
1097 
1098 	dev_dbg(&port->dev, "port number is %d\n", port->number);
1099 	dev_dbg(&port->dev, "serial number is %d\n", port->serial->minor);
1100 	dev_dbg(&port->dev, "Bulkin endpoint is %d\n", port->bulk_in_endpointAddress);
1101 	dev_dbg(&port->dev, "BulkOut endpoint is %d\n", port->bulk_out_endpointAddress);
1102 	dev_dbg(&port->dev, "Interrupt endpoint is %d\n", port->interrupt_in_endpointAddress);
1103 	dev_dbg(&port->dev, "port's number in the device is %d\n", mos7840_port->port_num);
1104 	mos7840_port->read_urb = port->read_urb;
1105 
1106 	/* set up our bulk in urb */
1107 	if ((serial->num_ports == 2)
1108 		&& ((((__u16)port->number -
1109 			(__u16)(port->serial->minor)) % 2) != 0)) {
1110 		usb_fill_bulk_urb(mos7840_port->read_urb,
1111 			serial->dev,
1112 			usb_rcvbulkpipe(serial->dev,
1113 				(port->bulk_in_endpointAddress) + 2),
1114 			port->bulk_in_buffer,
1115 			mos7840_port->read_urb->transfer_buffer_length,
1116 			mos7840_bulk_in_callback, mos7840_port);
1117 	} else {
1118 		usb_fill_bulk_urb(mos7840_port->read_urb,
1119 			serial->dev,
1120 			usb_rcvbulkpipe(serial->dev,
1121 				port->bulk_in_endpointAddress),
1122 			port->bulk_in_buffer,
1123 			mos7840_port->read_urb->transfer_buffer_length,
1124 			mos7840_bulk_in_callback, mos7840_port);
1125 	}
1126 
1127 	dev_dbg(&port->dev, "%s: bulkin endpoint is %d\n", __func__, port->bulk_in_endpointAddress);
1128 	mos7840_port->read_urb_busy = true;
1129 	response = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
1130 	if (response) {
1131 		dev_err(&port->dev, "%s - Error %d submitting control urb\n",
1132 			__func__, response);
1133 		mos7840_port->read_urb_busy = false;
1134 	}
1135 
1136 	/* initialize our wait queues */
1137 	init_waitqueue_head(&mos7840_port->wait_chase);
1138 	init_waitqueue_head(&mos7840_port->delta_msr_wait);
1139 
1140 	/* initialize our icount structure */
1141 	memset(&(mos7840_port->icount), 0x00, sizeof(mos7840_port->icount));
1142 
1143 	/* initialize our port settings */
1144 	/* Must set to enable ints! */
1145 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1146 	/* send a open port command */
1147 	mos7840_port->open = 1;
1148 	/* mos7840_change_port_settings(mos7840_port,old_termios); */
1149 	mos7840_port->icount.tx = 0;
1150 	mos7840_port->icount.rx = 0;
1151 
1152 	return 0;
1153 }
1154 
1155 /*****************************************************************************
1156  * mos7840_chars_in_buffer
1157  *	this function is called by the tty driver when it wants to know how many
1158  *	bytes of data we currently have outstanding in the port (data that has
1159  *	been written, but hasn't made it out the port yet)
1160  *	If successful, we return the number of bytes left to be written in the
1161  *	system,
1162  *	Otherwise we return zero.
1163  *****************************************************************************/
1164 
1165 static int mos7840_chars_in_buffer(struct tty_struct *tty)
1166 {
1167 	struct usb_serial_port *port = tty->driver_data;
1168 	int i;
1169 	int chars = 0;
1170 	unsigned long flags;
1171 	struct moschip_port *mos7840_port;
1172 
1173 	if (mos7840_port_paranoia_check(port, __func__))
1174 		return 0;
1175 
1176 	mos7840_port = mos7840_get_port_private(port);
1177 	if (mos7840_port == NULL)
1178 		return 0;
1179 
1180 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1181 	for (i = 0; i < NUM_URBS; ++i) {
1182 		if (mos7840_port->busy[i]) {
1183 			struct urb *urb = mos7840_port->write_urb_pool[i];
1184 			chars += urb->transfer_buffer_length;
1185 		}
1186 	}
1187 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1188 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1189 	return chars;
1190 
1191 }
1192 
1193 /*****************************************************************************
1194  * mos7840_close
1195  *	this function is called by the tty driver when a port is closed
1196  *****************************************************************************/
1197 
1198 static void mos7840_close(struct usb_serial_port *port)
1199 {
1200 	struct usb_serial *serial;
1201 	struct moschip_port *mos7840_port;
1202 	struct moschip_port *port0;
1203 	int j;
1204 	__u16 Data;
1205 
1206 	if (mos7840_port_paranoia_check(port, __func__))
1207 		return;
1208 
1209 	serial = mos7840_get_usb_serial(port, __func__);
1210 	if (!serial)
1211 		return;
1212 
1213 	mos7840_port = mos7840_get_port_private(port);
1214 	port0 = mos7840_get_port_private(serial->port[0]);
1215 
1216 	if (mos7840_port == NULL || port0 == NULL)
1217 		return;
1218 
1219 	for (j = 0; j < NUM_URBS; ++j)
1220 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
1221 
1222 	/* Freeing Write URBs */
1223 	for (j = 0; j < NUM_URBS; ++j) {
1224 		if (mos7840_port->write_urb_pool[j]) {
1225 			if (mos7840_port->write_urb_pool[j]->transfer_buffer)
1226 				kfree(mos7840_port->write_urb_pool[j]->
1227 				      transfer_buffer);
1228 
1229 			usb_free_urb(mos7840_port->write_urb_pool[j]);
1230 		}
1231 	}
1232 
1233 	/* While closing port, shutdown all bulk read, write  *
1234 	 * and interrupt read if they exists                  */
1235 	if (serial->dev) {
1236 		if (mos7840_port->write_urb) {
1237 			dev_dbg(&port->dev, "%s", "Shutdown bulk write\n");
1238 			usb_kill_urb(mos7840_port->write_urb);
1239 		}
1240 		if (mos7840_port->read_urb) {
1241 			dev_dbg(&port->dev, "%s", "Shutdown bulk read\n");
1242 			usb_kill_urb(mos7840_port->read_urb);
1243 			mos7840_port->read_urb_busy = false;
1244 		}
1245 		if ((&mos7840_port->control_urb)) {
1246 			dev_dbg(&port->dev, "%s", "Shutdown control read\n");
1247 			/*/      usb_kill_urb (mos7840_port->control_urb); */
1248 		}
1249 	}
1250 /*      if(mos7840_port->ctrl_buf != NULL) */
1251 /*              kfree(mos7840_port->ctrl_buf); */
1252 	port0->open_ports--;
1253 	dev_dbg(&port->dev, "%s in close%d:in port%d\n", __func__, port0->open_ports, port->number);
1254 	if (port0->open_ports == 0) {
1255 		if (serial->port[0]->interrupt_in_urb) {
1256 			dev_dbg(&port->dev, "Shutdown interrupt_in_urb\n");
1257 			usb_kill_urb(serial->port[0]->interrupt_in_urb);
1258 		}
1259 	}
1260 
1261 	if (mos7840_port->write_urb) {
1262 		/* if this urb had a transfer buffer already (old tx) free it */
1263 		if (mos7840_port->write_urb->transfer_buffer != NULL)
1264 			kfree(mos7840_port->write_urb->transfer_buffer);
1265 		usb_free_urb(mos7840_port->write_urb);
1266 	}
1267 
1268 	Data = 0x0;
1269 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1270 
1271 	Data = 0x00;
1272 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1273 
1274 	mos7840_port->open = 0;
1275 }
1276 
1277 /************************************************************************
1278  *
1279  * mos7840_block_until_chase_response
1280  *
1281  *	This function will block the close until one of the following:
1282  *		1. Response to our Chase comes from mos7840
1283  *		2. A timeout of 10 seconds without activity has expired
1284  *		   (1K of mos7840 data @ 2400 baud ==> 4 sec to empty)
1285  *
1286  ************************************************************************/
1287 
1288 static void mos7840_block_until_chase_response(struct tty_struct *tty,
1289 					struct moschip_port *mos7840_port)
1290 {
1291 	int timeout = msecs_to_jiffies(1000);
1292 	int wait = 10;
1293 	int count;
1294 
1295 	while (1) {
1296 		count = mos7840_chars_in_buffer(tty);
1297 
1298 		/* Check for Buffer status */
1299 		if (count <= 0)
1300 			return;
1301 
1302 		/* Block the thread for a while */
1303 		interruptible_sleep_on_timeout(&mos7840_port->wait_chase,
1304 					       timeout);
1305 		/* No activity.. count down section */
1306 		wait--;
1307 		if (wait == 0) {
1308 			dev_dbg(&mos7840_port->port->dev, "%s - TIMEOUT\n", __func__);
1309 			return;
1310 		} else {
1311 			/* Reset timeout value back to seconds */
1312 			wait = 10;
1313 		}
1314 	}
1315 
1316 }
1317 
1318 /*****************************************************************************
1319  * mos7840_break
1320  *	this function sends a break to the port
1321  *****************************************************************************/
1322 static void mos7840_break(struct tty_struct *tty, int break_state)
1323 {
1324 	struct usb_serial_port *port = tty->driver_data;
1325 	unsigned char data;
1326 	struct usb_serial *serial;
1327 	struct moschip_port *mos7840_port;
1328 
1329 	if (mos7840_port_paranoia_check(port, __func__))
1330 		return;
1331 
1332 	serial = mos7840_get_usb_serial(port, __func__);
1333 	if (!serial)
1334 		return;
1335 
1336 	mos7840_port = mos7840_get_port_private(port);
1337 
1338 	if (mos7840_port == NULL)
1339 		return;
1340 
1341 	if (serial->dev)
1342 		/* flush and block until tx is empty */
1343 		mos7840_block_until_chase_response(tty, mos7840_port);
1344 
1345 	if (break_state == -1)
1346 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
1347 	else
1348 		data = mos7840_port->shadowLCR & ~LCR_SET_BREAK;
1349 
1350 	/* FIXME: no locking on shadowLCR anywhere in driver */
1351 	mos7840_port->shadowLCR = data;
1352 	dev_dbg(&port->dev, "%s mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1353 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER,
1354 			     mos7840_port->shadowLCR);
1355 }
1356 
1357 /*****************************************************************************
1358  * mos7840_write_room
1359  *	this function is called by the tty driver when it wants to know how many
1360  *	bytes of data we can accept for a specific port.
1361  *	If successful, we return the amount of room that we have for this port
1362  *	Otherwise we return a negative error number.
1363  *****************************************************************************/
1364 
1365 static int mos7840_write_room(struct tty_struct *tty)
1366 {
1367 	struct usb_serial_port *port = tty->driver_data;
1368 	int i;
1369 	int room = 0;
1370 	unsigned long flags;
1371 	struct moschip_port *mos7840_port;
1372 
1373 	if (mos7840_port_paranoia_check(port, __func__))
1374 		return -1;
1375 
1376 	mos7840_port = mos7840_get_port_private(port);
1377 	if (mos7840_port == NULL)
1378 		return -1;
1379 
1380 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1381 	for (i = 0; i < NUM_URBS; ++i) {
1382 		if (!mos7840_port->busy[i])
1383 			room += URB_TRANSFER_BUFFER_SIZE;
1384 	}
1385 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1386 
1387 	room = (room == 0) ? 0 : room - URB_TRANSFER_BUFFER_SIZE + 1;
1388 	dev_dbg(&mos7840_port->port->dev, "%s - returns %d\n", __func__, room);
1389 	return room;
1390 
1391 }
1392 
1393 /*****************************************************************************
1394  * mos7840_write
1395  *	this function is called by the tty driver when data should be written to
1396  *	the port.
1397  *	If successful, we return the number of bytes written, otherwise we
1398  *      return a negative error number.
1399  *****************************************************************************/
1400 
1401 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
1402 			 const unsigned char *data, int count)
1403 {
1404 	int status;
1405 	int i;
1406 	int bytes_sent = 0;
1407 	int transfer_size;
1408 	unsigned long flags;
1409 
1410 	struct moschip_port *mos7840_port;
1411 	struct usb_serial *serial;
1412 	struct urb *urb;
1413 	/* __u16 Data; */
1414 	const unsigned char *current_position = data;
1415 	unsigned char *data1;
1416 
1417 #ifdef NOTMOS7840
1418 	Data = 0x00;
1419 	status = mos7840_get_uart_reg(port, LINE_CONTROL_REGISTER, &Data);
1420 	mos7840_port->shadowLCR = Data;
1421 	dev_dbg(&port->dev, "%s: LINE_CONTROL_REGISTER is %x\n", __func__, Data);
1422 	dev_dbg(&port->dev, "%s: mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1423 
1424 	/* Data = 0x03; */
1425 	/* status = mos7840_set_uart_reg(port,LINE_CONTROL_REGISTER,Data); */
1426 	/* mos7840_port->shadowLCR=Data;//Need to add later */
1427 
1428 	Data |= SERIAL_LCR_DLAB;	/* data latch enable in LCR 0x80 */
1429 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1430 
1431 	/* Data = 0x0c; */
1432 	/* status = mos7840_set_uart_reg(port,DIVISOR_LATCH_LSB,Data); */
1433 	Data = 0x00;
1434 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_LSB, &Data);
1435 	dev_dbg(&port->dev, "%s: DLL value is %x\n", __func__, Data);
1436 
1437 	Data = 0x0;
1438 	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_MSB, &Data);
1439 	dev_dbg(&port->dev, "%s: DLM value is %x\n", __func__, Data);
1440 
1441 	Data = Data & ~SERIAL_LCR_DLAB;
1442 	dev_dbg(&port->dev, "%s: mos7840_port->shadowLCR is %x\n", __func__, mos7840_port->shadowLCR);
1443 	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1444 #endif
1445 
1446 	if (mos7840_port_paranoia_check(port, __func__))
1447 		return -1;
1448 
1449 	serial = port->serial;
1450 	if (mos7840_serial_paranoia_check(serial, __func__))
1451 		return -1;
1452 
1453 	mos7840_port = mos7840_get_port_private(port);
1454 	if (mos7840_port == NULL)
1455 		return -1;
1456 
1457 	/* try to find a free urb in the list */
1458 	urb = NULL;
1459 
1460 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
1461 	for (i = 0; i < NUM_URBS; ++i) {
1462 		if (!mos7840_port->busy[i]) {
1463 			mos7840_port->busy[i] = 1;
1464 			urb = mos7840_port->write_urb_pool[i];
1465 			dev_dbg(&port->dev, "URB:%d\n", i);
1466 			break;
1467 		}
1468 	}
1469 	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
1470 
1471 	if (urb == NULL) {
1472 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1473 		goto exit;
1474 	}
1475 
1476 	if (urb->transfer_buffer == NULL) {
1477 		urb->transfer_buffer =
1478 		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
1479 
1480 		if (urb->transfer_buffer == NULL) {
1481 			dev_err_console(port, "%s no more kernel memory...\n",
1482 				__func__);
1483 			goto exit;
1484 		}
1485 	}
1486 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1487 
1488 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1489 
1490 	/* fill urb with data and submit  */
1491 	if ((serial->num_ports == 2)
1492 		&& ((((__u16)port->number -
1493 			(__u16)(port->serial->minor)) % 2) != 0)) {
1494 		usb_fill_bulk_urb(urb,
1495 			serial->dev,
1496 			usb_sndbulkpipe(serial->dev,
1497 				(port->bulk_out_endpointAddress) + 2),
1498 			urb->transfer_buffer,
1499 			transfer_size,
1500 			mos7840_bulk_out_data_callback, mos7840_port);
1501 	} else {
1502 		usb_fill_bulk_urb(urb,
1503 			serial->dev,
1504 			usb_sndbulkpipe(serial->dev,
1505 				port->bulk_out_endpointAddress),
1506 			urb->transfer_buffer,
1507 			transfer_size,
1508 			mos7840_bulk_out_data_callback, mos7840_port);
1509 	}
1510 
1511 	data1 = urb->transfer_buffer;
1512 	dev_dbg(&port->dev, "bulkout endpoint is %d\n", port->bulk_out_endpointAddress);
1513 
1514 	/* Turn on LED */
1515 	if (mos7840_port->has_led && !mos7840_port->led_flag) {
1516 		mos7840_port->led_flag = true;
1517 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0301);
1518 		mod_timer(&mos7840_port->led_timer1,
1519 				jiffies + msecs_to_jiffies(LED_ON_MS));
1520 	}
1521 
1522 	/* send it down the pipe */
1523 	status = usb_submit_urb(urb, GFP_ATOMIC);
1524 
1525 	if (status) {
1526 		mos7840_port->busy[i] = 0;
1527 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1528 			"with status = %d\n", __func__, status);
1529 		bytes_sent = status;
1530 		goto exit;
1531 	}
1532 	bytes_sent = transfer_size;
1533 	mos7840_port->icount.tx += transfer_size;
1534 	smp_wmb();
1535 	dev_dbg(&port->dev, "mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);
1536 exit:
1537 	return bytes_sent;
1538 
1539 }
1540 
1541 /*****************************************************************************
1542  * mos7840_throttle
1543  *	this function is called by the tty driver when it wants to stop the data
1544  *	being read from the port.
1545  *****************************************************************************/
1546 
1547 static void mos7840_throttle(struct tty_struct *tty)
1548 {
1549 	struct usb_serial_port *port = tty->driver_data;
1550 	struct moschip_port *mos7840_port;
1551 	int status;
1552 
1553 	if (mos7840_port_paranoia_check(port, __func__))
1554 		return;
1555 
1556 	mos7840_port = mos7840_get_port_private(port);
1557 
1558 	if (mos7840_port == NULL)
1559 		return;
1560 
1561 	if (!mos7840_port->open) {
1562 		dev_dbg(&port->dev, "%s", "port not opened\n");
1563 		return;
1564 	}
1565 
1566 	/* if we are implementing XON/XOFF, send the stop character */
1567 	if (I_IXOFF(tty)) {
1568 		unsigned char stop_char = STOP_CHAR(tty);
1569 		status = mos7840_write(tty, port, &stop_char, 1);
1570 		if (status <= 0)
1571 			return;
1572 	}
1573 	/* if we are implementing RTS/CTS, toggle that line */
1574 	if (tty->termios.c_cflag & CRTSCTS) {
1575 		mos7840_port->shadowMCR &= ~MCR_RTS;
1576 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1577 					 mos7840_port->shadowMCR);
1578 		if (status < 0)
1579 			return;
1580 	}
1581 }
1582 
1583 /*****************************************************************************
1584  * mos7840_unthrottle
1585  *	this function is called by the tty driver when it wants to resume
1586  *	the data being read from the port (called after mos7840_throttle is
1587  *	called)
1588  *****************************************************************************/
1589 static void mos7840_unthrottle(struct tty_struct *tty)
1590 {
1591 	struct usb_serial_port *port = tty->driver_data;
1592 	int status;
1593 	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
1594 
1595 	if (mos7840_port_paranoia_check(port, __func__))
1596 		return;
1597 
1598 	if (mos7840_port == NULL)
1599 		return;
1600 
1601 	if (!mos7840_port->open) {
1602 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1603 		return;
1604 	}
1605 
1606 	/* if we are implementing XON/XOFF, send the start character */
1607 	if (I_IXOFF(tty)) {
1608 		unsigned char start_char = START_CHAR(tty);
1609 		status = mos7840_write(tty, port, &start_char, 1);
1610 		if (status <= 0)
1611 			return;
1612 	}
1613 
1614 	/* if we are implementing RTS/CTS, toggle that line */
1615 	if (tty->termios.c_cflag & CRTSCTS) {
1616 		mos7840_port->shadowMCR |= MCR_RTS;
1617 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1618 					 mos7840_port->shadowMCR);
1619 		if (status < 0)
1620 			return;
1621 	}
1622 }
1623 
1624 static int mos7840_tiocmget(struct tty_struct *tty)
1625 {
1626 	struct usb_serial_port *port = tty->driver_data;
1627 	struct moschip_port *mos7840_port;
1628 	unsigned int result;
1629 	__u16 msr;
1630 	__u16 mcr;
1631 	int status;
1632 	mos7840_port = mos7840_get_port_private(port);
1633 
1634 	if (mos7840_port == NULL)
1635 		return -ENODEV;
1636 
1637 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
1638 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
1639 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
1640 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
1641 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
1642 	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
1643 	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
1644 	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
1645 	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);
1646 
1647 	dev_dbg(&port->dev, "%s - 0x%04X\n", __func__, result);
1648 
1649 	return result;
1650 }
1651 
1652 static int mos7840_tiocmset(struct tty_struct *tty,
1653 			    unsigned int set, unsigned int clear)
1654 {
1655 	struct usb_serial_port *port = tty->driver_data;
1656 	struct moschip_port *mos7840_port;
1657 	unsigned int mcr;
1658 	int status;
1659 
1660 	mos7840_port = mos7840_get_port_private(port);
1661 
1662 	if (mos7840_port == NULL)
1663 		return -ENODEV;
1664 
1665 	/* FIXME: What locks the port registers ? */
1666 	mcr = mos7840_port->shadowMCR;
1667 	if (clear & TIOCM_RTS)
1668 		mcr &= ~MCR_RTS;
1669 	if (clear & TIOCM_DTR)
1670 		mcr &= ~MCR_DTR;
1671 	if (clear & TIOCM_LOOP)
1672 		mcr &= ~MCR_LOOPBACK;
1673 
1674 	if (set & TIOCM_RTS)
1675 		mcr |= MCR_RTS;
1676 	if (set & TIOCM_DTR)
1677 		mcr |= MCR_DTR;
1678 	if (set & TIOCM_LOOP)
1679 		mcr |= MCR_LOOPBACK;
1680 
1681 	mos7840_port->shadowMCR = mcr;
1682 
1683 	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
1684 	if (status < 0) {
1685 		dev_dbg(&port->dev, "setting MODEM_CONTROL_REGISTER Failed\n");
1686 		return status;
1687 	}
1688 
1689 	return 0;
1690 }
1691 
1692 /*****************************************************************************
1693  * mos7840_calc_baud_rate_divisor
1694  *	this function calculates the proper baud rate divisor for the specified
1695  *	baud rate.
1696  *****************************************************************************/
1697 static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
1698 					  int baudRate, int *divisor,
1699 					  __u16 *clk_sel_val)
1700 {
1701 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudRate);
1702 
1703 	if (baudRate <= 115200) {
1704 		*divisor = 115200 / baudRate;
1705 		*clk_sel_val = 0x0;
1706 	}
1707 	if ((baudRate > 115200) && (baudRate <= 230400)) {
1708 		*divisor = 230400 / baudRate;
1709 		*clk_sel_val = 0x10;
1710 	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
1711 		*divisor = 403200 / baudRate;
1712 		*clk_sel_val = 0x20;
1713 	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
1714 		*divisor = 460800 / baudRate;
1715 		*clk_sel_val = 0x30;
1716 	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
1717 		*divisor = 806400 / baudRate;
1718 		*clk_sel_val = 0x40;
1719 	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
1720 		*divisor = 921600 / baudRate;
1721 		*clk_sel_val = 0x50;
1722 	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
1723 		*divisor = 1572864 / baudRate;
1724 		*clk_sel_val = 0x60;
1725 	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
1726 		*divisor = 3145728 / baudRate;
1727 		*clk_sel_val = 0x70;
1728 	}
1729 	return 0;
1730 
1731 #ifdef NOTMCS7840
1732 
1733 	for (i = 0; i < ARRAY_SIZE(mos7840_divisor_table); i++) {
1734 		if (mos7840_divisor_table[i].BaudRate == baudrate) {
1735 			*divisor = mos7840_divisor_table[i].Divisor;
1736 			return 0;
1737 		}
1738 	}
1739 
1740 	/* After trying for all the standard baud rates    *
1741 	 * Try calculating the divisor for this baud rate  */
1742 
1743 	if (baudrate > 75 && baudrate < 230400) {
1744 		/* get the divisor */
1745 		custom = (__u16) (230400L / baudrate);
1746 
1747 		/* Check for round off */
1748 		round1 = (__u16) (2304000L / baudrate);
1749 		round = (__u16) (round1 - (custom * 10));
1750 		if (round > 4)
1751 			custom++;
1752 		*divisor = custom;
1753 
1754 		dev_dbg(&port->dev, " Baud %d = %d\n", baudrate, custom);
1755 		return 0;
1756 	}
1757 
1758 	dev_dbg(&port->dev, "%s", " Baud calculation Failed...\n");
1759 	return -1;
1760 #endif
1761 }
1762 
1763 /*****************************************************************************
1764  * mos7840_send_cmd_write_baud_rate
1765  *	this function sends the proper command to change the baud rate of the
1766  *	specified port.
1767  *****************************************************************************/
1768 
1769 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
1770 					    int baudRate)
1771 {
1772 	int divisor = 0;
1773 	int status;
1774 	__u16 Data;
1775 	unsigned char number;
1776 	__u16 clk_sel_val;
1777 	struct usb_serial_port *port;
1778 
1779 	if (mos7840_port == NULL)
1780 		return -1;
1781 
1782 	port = mos7840_port->port;
1783 	if (mos7840_port_paranoia_check(port, __func__))
1784 		return -1;
1785 
1786 	if (mos7840_serial_paranoia_check(port->serial, __func__))
1787 		return -1;
1788 
1789 	number = mos7840_port->port->number - mos7840_port->port->serial->minor;
1790 
1791 	dev_dbg(&port->dev, "%s - port = %d, baud = %d\n", __func__,
1792 		mos7840_port->port->number, baudRate);
1793 	/* reset clk_uart_sel in spregOffset */
1794 	if (baudRate > 115200) {
1795 #ifdef HW_flow_control
1796 		/* NOTE: need to see the pther register to modify */
1797 		/* setting h/w flow control bit to 1 */
1798 		Data = 0x2b;
1799 		mos7840_port->shadowMCR = Data;
1800 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1801 									Data);
1802 		if (status < 0) {
1803 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1804 			return -1;
1805 		}
1806 #endif
1807 
1808 	} else {
1809 #ifdef HW_flow_control
1810 		/* setting h/w flow control bit to 0 */
1811 		Data = 0xb;
1812 		mos7840_port->shadowMCR = Data;
1813 		status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
1814 									Data);
1815 		if (status < 0) {
1816 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1817 			return -1;
1818 		}
1819 #endif
1820 
1821 	}
1822 
1823 	if (1) {		/* baudRate <= 115200) */
1824 		clk_sel_val = 0x0;
1825 		Data = 0x0;
1826 		status = mos7840_calc_baud_rate_divisor(port, baudRate, &divisor,
1827 						   &clk_sel_val);
1828 		status = mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
1829 								 &Data);
1830 		if (status < 0) {
1831 			dev_dbg(&port->dev, "reading spreg failed in set_serial_baud\n");
1832 			return -1;
1833 		}
1834 		Data = (Data & 0x8f) | clk_sel_val;
1835 		status = mos7840_set_reg_sync(port, mos7840_port->SpRegOffset,
1836 								Data);
1837 		if (status < 0) {
1838 			dev_dbg(&port->dev, "Writing spreg failed in set_serial_baud\n");
1839 			return -1;
1840 		}
1841 		/* Calculate the Divisor */
1842 
1843 		if (status) {
1844 			dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1845 			return status;
1846 		}
1847 		/* Enable access to divisor latch */
1848 		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
1849 		mos7840_port->shadowLCR = Data;
1850 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1851 
1852 		/* Write the divisor */
1853 		Data = (unsigned char)(divisor & 0xff);
1854 		dev_dbg(&port->dev, "set_serial_baud Value to write DLL is %x\n", Data);
1855 		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);
1856 
1857 		Data = (unsigned char)((divisor & 0xff00) >> 8);
1858 		dev_dbg(&port->dev, "set_serial_baud Value to write DLM is %x\n", Data);
1859 		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);
1860 
1861 		/* Disable access to divisor latch */
1862 		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
1863 		mos7840_port->shadowLCR = Data;
1864 		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1865 
1866 	}
1867 	return status;
1868 }
1869 
1870 /*****************************************************************************
1871  * mos7840_change_port_settings
1872  *	This routine is called to set the UART on the device to match
1873  *      the specified new settings.
1874  *****************************************************************************/
1875 
1876 static void mos7840_change_port_settings(struct tty_struct *tty,
1877 	struct moschip_port *mos7840_port, struct ktermios *old_termios)
1878 {
1879 	int baud;
1880 	unsigned cflag;
1881 	unsigned iflag;
1882 	__u8 lData;
1883 	__u8 lParity;
1884 	__u8 lStop;
1885 	int status;
1886 	__u16 Data;
1887 	struct usb_serial_port *port;
1888 	struct usb_serial *serial;
1889 
1890 	if (mos7840_port == NULL)
1891 		return;
1892 
1893 	port = mos7840_port->port;
1894 
1895 	if (mos7840_port_paranoia_check(port, __func__))
1896 		return;
1897 
1898 	if (mos7840_serial_paranoia_check(port->serial, __func__))
1899 		return;
1900 
1901 	serial = port->serial;
1902 
1903 	if (!mos7840_port->open) {
1904 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1905 		return;
1906 	}
1907 
1908 	lData = LCR_BITS_8;
1909 	lStop = LCR_STOP_1;
1910 	lParity = LCR_PAR_NONE;
1911 
1912 	cflag = tty->termios.c_cflag;
1913 	iflag = tty->termios.c_iflag;
1914 
1915 	/* Change the number of bits */
1916 	if (cflag & CSIZE) {
1917 		switch (cflag & CSIZE) {
1918 		case CS5:
1919 			lData = LCR_BITS_5;
1920 			break;
1921 
1922 		case CS6:
1923 			lData = LCR_BITS_6;
1924 			break;
1925 
1926 		case CS7:
1927 			lData = LCR_BITS_7;
1928 			break;
1929 		default:
1930 		case CS8:
1931 			lData = LCR_BITS_8;
1932 			break;
1933 		}
1934 	}
1935 	/* Change the Parity bit */
1936 	if (cflag & PARENB) {
1937 		if (cflag & PARODD) {
1938 			lParity = LCR_PAR_ODD;
1939 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1940 		} else {
1941 			lParity = LCR_PAR_EVEN;
1942 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1943 		}
1944 
1945 	} else {
1946 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1947 	}
1948 
1949 	if (cflag & CMSPAR)
1950 		lParity = lParity | 0x20;
1951 
1952 	/* Change the Stop bit */
1953 	if (cflag & CSTOPB) {
1954 		lStop = LCR_STOP_2;
1955 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1956 	} else {
1957 		lStop = LCR_STOP_1;
1958 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1959 	}
1960 
1961 	/* Update the LCR with the correct value */
1962 	mos7840_port->shadowLCR &=
1963 	    ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1964 	mos7840_port->shadowLCR |= (lData | lParity | lStop);
1965 
1966 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is %x\n", __func__,
1967 		mos7840_port->shadowLCR);
1968 	/* Disable Interrupts */
1969 	Data = 0x00;
1970 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
1971 
1972 	Data = 0x00;
1973 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1974 
1975 	Data = 0xcf;
1976 	mos7840_set_uart_reg(port, FIFO_CONTROL_REGISTER, Data);
1977 
1978 	/* Send the updated LCR value to the mos7840 */
1979 	Data = mos7840_port->shadowLCR;
1980 
1981 	mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
1982 
1983 	Data = 0x00b;
1984 	mos7840_port->shadowMCR = Data;
1985 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1986 	Data = 0x00b;
1987 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
1988 
1989 	/* set up the MCR register and send it to the mos7840 */
1990 
1991 	mos7840_port->shadowMCR = MCR_MASTER_IE;
1992 	if (cflag & CBAUD)
1993 		mos7840_port->shadowMCR |= (MCR_DTR | MCR_RTS);
1994 
1995 	if (cflag & CRTSCTS)
1996 		mos7840_port->shadowMCR |= (MCR_XON_ANY);
1997 	else
1998 		mos7840_port->shadowMCR &= ~(MCR_XON_ANY);
1999 
2000 	Data = mos7840_port->shadowMCR;
2001 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
2002 
2003 	/* Determine divisor based on baud rate */
2004 	baud = tty_get_baud_rate(tty);
2005 
2006 	if (!baud) {
2007 		/* pick a default, any default... */
2008 		dev_dbg(&port->dev, "%s", "Picked default baud...\n");
2009 		baud = 9600;
2010 	}
2011 
2012 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
2013 	status = mos7840_send_cmd_write_baud_rate(mos7840_port, baud);
2014 
2015 	/* Enable Interrupts */
2016 	Data = 0x0c;
2017 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
2018 
2019 	if (mos7840_port->read_urb_busy == false) {
2020 		mos7840_port->read_urb_busy = true;
2021 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2022 		if (status) {
2023 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
2024 			    status);
2025 			mos7840_port->read_urb_busy = false;
2026 		}
2027 	}
2028 	wake_up(&mos7840_port->delta_msr_wait);
2029 	mos7840_port->delta_msr_cond = 1;
2030 	dev_dbg(&port->dev, "%s - mos7840_port->shadowLCR is End %x\n", __func__,
2031 		mos7840_port->shadowLCR);
2032 }
2033 
2034 /*****************************************************************************
2035  * mos7840_set_termios
2036  *	this function is called by the tty driver when it wants to change
2037  *	the termios structure
2038  *****************************************************************************/
2039 
2040 static void mos7840_set_termios(struct tty_struct *tty,
2041 				struct usb_serial_port *port,
2042 				struct ktermios *old_termios)
2043 {
2044 	int status;
2045 	unsigned int cflag;
2046 	struct usb_serial *serial;
2047 	struct moschip_port *mos7840_port;
2048 
2049 	if (mos7840_port_paranoia_check(port, __func__))
2050 		return;
2051 
2052 	serial = port->serial;
2053 
2054 	if (mos7840_serial_paranoia_check(serial, __func__))
2055 		return;
2056 
2057 	mos7840_port = mos7840_get_port_private(port);
2058 
2059 	if (mos7840_port == NULL)
2060 		return;
2061 
2062 	if (!mos7840_port->open) {
2063 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
2064 		return;
2065 	}
2066 
2067 	dev_dbg(&port->dev, "%s", "setting termios - \n");
2068 
2069 	cflag = tty->termios.c_cflag;
2070 
2071 	dev_dbg(&port->dev, "%s - clfag %08x iflag %08x\n", __func__,
2072 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
2073 	dev_dbg(&port->dev, "%s - old clfag %08x old iflag %08x\n", __func__,
2074 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
2075 	dev_dbg(&port->dev, "%s - port %d\n", __func__, port->number);
2076 
2077 	/* change the port settings to the new ones specified */
2078 
2079 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
2080 
2081 	if (!mos7840_port->read_urb) {
2082 		dev_dbg(&port->dev, "%s", "URB KILLED !!!!!\n");
2083 		return;
2084 	}
2085 
2086 	if (mos7840_port->read_urb_busy == false) {
2087 		mos7840_port->read_urb_busy = true;
2088 		status = usb_submit_urb(mos7840_port->read_urb, GFP_ATOMIC);
2089 		if (status) {
2090 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n",
2091 			    status);
2092 			mos7840_port->read_urb_busy = false;
2093 		}
2094 	}
2095 }
2096 
2097 /*****************************************************************************
2098  * mos7840_get_lsr_info - get line status register info
2099  *
2100  * Purpose: Let user call ioctl() to get info when the UART physically
2101  * 	    is emptied.  On bus types like RS485, the transmitter must
2102  * 	    release the bus after transmitting. This must be done when
2103  * 	    the transmit shift register is empty, not be done when the
2104  * 	    transmit holding register is empty.  This functionality
2105  * 	    allows an RS485 driver to be written in user space.
2106  *****************************************************************************/
2107 
2108 static int mos7840_get_lsr_info(struct tty_struct *tty,
2109 				unsigned int __user *value)
2110 {
2111 	int count;
2112 	unsigned int result = 0;
2113 
2114 	count = mos7840_chars_in_buffer(tty);
2115 	if (count == 0)
2116 		result = TIOCSER_TEMT;
2117 
2118 	if (copy_to_user(value, &result, sizeof(int)))
2119 		return -EFAULT;
2120 	return 0;
2121 }
2122 
2123 /*****************************************************************************
2124  * mos7840_get_serial_info
2125  *      function to get information about serial port
2126  *****************************************************************************/
2127 
2128 static int mos7840_get_serial_info(struct moschip_port *mos7840_port,
2129 				   struct serial_struct __user *retinfo)
2130 {
2131 	struct serial_struct tmp;
2132 
2133 	if (mos7840_port == NULL)
2134 		return -1;
2135 
2136 	if (!retinfo)
2137 		return -EFAULT;
2138 
2139 	memset(&tmp, 0, sizeof(tmp));
2140 
2141 	tmp.type = PORT_16550A;
2142 	tmp.line = mos7840_port->port->serial->minor;
2143 	tmp.port = mos7840_port->port->number;
2144 	tmp.irq = 0;
2145 	tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
2146 	tmp.xmit_fifo_size = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
2147 	tmp.baud_base = 9600;
2148 	tmp.close_delay = 5 * HZ;
2149 	tmp.closing_wait = 30 * HZ;
2150 
2151 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
2152 		return -EFAULT;
2153 	return 0;
2154 }
2155 
2156 static int mos7840_get_icount(struct tty_struct *tty,
2157 			struct serial_icounter_struct *icount)
2158 {
2159 	struct usb_serial_port *port = tty->driver_data;
2160 	struct moschip_port *mos7840_port;
2161 	struct async_icount cnow;
2162 
2163 	mos7840_port = mos7840_get_port_private(port);
2164 	cnow = mos7840_port->icount;
2165 
2166 	smp_rmb();
2167 	icount->cts = cnow.cts;
2168 	icount->dsr = cnow.dsr;
2169 	icount->rng = cnow.rng;
2170 	icount->dcd = cnow.dcd;
2171 	icount->rx = cnow.rx;
2172 	icount->tx = cnow.tx;
2173 	icount->frame = cnow.frame;
2174 	icount->overrun = cnow.overrun;
2175 	icount->parity = cnow.parity;
2176 	icount->brk = cnow.brk;
2177 	icount->buf_overrun = cnow.buf_overrun;
2178 
2179 	dev_dbg(&port->dev, "%s TIOCGICOUNT RX=%d, TX=%d\n", __func__,
2180 		icount->rx, icount->tx);
2181 	return 0;
2182 }
2183 
2184 /*****************************************************************************
2185  * SerialIoctl
2186  *	this function handles any ioctl calls to the driver
2187  *****************************************************************************/
2188 
2189 static int mos7840_ioctl(struct tty_struct *tty,
2190 			 unsigned int cmd, unsigned long arg)
2191 {
2192 	struct usb_serial_port *port = tty->driver_data;
2193 	void __user *argp = (void __user *)arg;
2194 	struct moschip_port *mos7840_port;
2195 
2196 	struct async_icount cnow;
2197 	struct async_icount cprev;
2198 
2199 	if (mos7840_port_paranoia_check(port, __func__))
2200 		return -1;
2201 
2202 	mos7840_port = mos7840_get_port_private(port);
2203 
2204 	if (mos7840_port == NULL)
2205 		return -1;
2206 
2207 	dev_dbg(&port->dev, "%s - cmd = 0x%x\n", __func__, cmd);
2208 
2209 	switch (cmd) {
2210 		/* return number of bytes available */
2211 
2212 	case TIOCSERGETLSR:
2213 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
2214 		return mos7840_get_lsr_info(tty, argp);
2215 
2216 	case TIOCGSERIAL:
2217 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
2218 		return mos7840_get_serial_info(mos7840_port, argp);
2219 
2220 	case TIOCSSERIAL:
2221 		dev_dbg(&port->dev, "%s TIOCSSERIAL\n", __func__);
2222 		break;
2223 
2224 	case TIOCMIWAIT:
2225 		dev_dbg(&port->dev, "%s  TIOCMIWAIT\n", __func__);
2226 		cprev = mos7840_port->icount;
2227 		while (1) {
2228 			/* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */
2229 			mos7840_port->delta_msr_cond = 0;
2230 			wait_event_interruptible(mos7840_port->delta_msr_wait,
2231 						 (mos7840_port->
2232 						  delta_msr_cond == 1));
2233 
2234 			/* see if a signal did it */
2235 			if (signal_pending(current))
2236 				return -ERESTARTSYS;
2237 			cnow = mos7840_port->icount;
2238 			smp_rmb();
2239 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2240 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
2241 				return -EIO;	/* no change => error */
2242 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
2243 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
2244 			    ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
2245 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
2246 				return 0;
2247 			}
2248 			cprev = cnow;
2249 		}
2250 		/* NOTREACHED */
2251 		break;
2252 
2253 	default:
2254 		break;
2255 	}
2256 	return -ENOIOCTLCMD;
2257 }
2258 
2259 static int mos7810_check(struct usb_serial *serial)
2260 {
2261 	int i, pass_count = 0;
2262 	__u16 data = 0, mcr_data = 0;
2263 	__u16 test_pattern = 0x55AA;
2264 
2265 	/* Store MCR setting */
2266 	usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2267 		MCS_RDREQ, MCS_RD_RTYPE, 0x0300, MODEM_CONTROL_REGISTER,
2268 		&mcr_data, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2269 
2270 	for (i = 0; i < 16; i++) {
2271 		/* Send the 1-bit test pattern out to MCS7810 test pin */
2272 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2273 			MCS_WRREQ, MCS_WR_RTYPE,
2274 			(0x0300 | (((test_pattern >> i) & 0x0001) << 1)),
2275 			MODEM_CONTROL_REGISTER, NULL, 0, MOS_WDR_TIMEOUT);
2276 
2277 		/* Read the test pattern back */
2278 		usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2279 			MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, &data,
2280 			VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2281 
2282 		/* If this is a MCS7810 device, both test patterns must match */
2283 		if (((test_pattern >> i) ^ (~data >> 1)) & 0x0001)
2284 			break;
2285 
2286 		pass_count++;
2287 	}
2288 
2289 	/* Restore MCR setting */
2290 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), MCS_WRREQ,
2291 		MCS_WR_RTYPE, 0x0300 | mcr_data, MODEM_CONTROL_REGISTER, NULL,
2292 		0, MOS_WDR_TIMEOUT);
2293 
2294 	if (pass_count == 16)
2295 		return 1;
2296 
2297 	return 0;
2298 }
2299 
2300 static int mos7840_calc_num_ports(struct usb_serial *serial)
2301 {
2302 	__u16 data = 0x00;
2303 	int mos7840_num_ports;
2304 
2305 	usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2306 		MCS_RDREQ, MCS_RD_RTYPE, 0, GPIO_REGISTER, &data,
2307 		VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT);
2308 
2309 	if (serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7810 ||
2310 		serial->dev->descriptor.idProduct == MOSCHIP_DEVICE_ID_7820) {
2311 		device_type = serial->dev->descriptor.idProduct;
2312 	} else {
2313 		/* For a MCS7840 device GPIO0 must be set to 1 */
2314 		if ((data & 0x01) == 1)
2315 			device_type = MOSCHIP_DEVICE_ID_7840;
2316 		else if (mos7810_check(serial))
2317 			device_type = MOSCHIP_DEVICE_ID_7810;
2318 		else
2319 			device_type = MOSCHIP_DEVICE_ID_7820;
2320 	}
2321 
2322 	mos7840_num_ports = (device_type >> 4) & 0x000F;
2323 	serial->num_bulk_in = mos7840_num_ports;
2324 	serial->num_bulk_out = mos7840_num_ports;
2325 	serial->num_ports = mos7840_num_ports;
2326 
2327 	return mos7840_num_ports;
2328 }
2329 
2330 static int mos7840_port_probe(struct usb_serial_port *port)
2331 {
2332 	struct usb_serial *serial = port->serial;
2333 	struct moschip_port *mos7840_port;
2334 	int status;
2335 	int pnum;
2336 	__u16 Data;
2337 
2338 	/* we set up the pointers to the endpoints in the mos7840_open *
2339 	 * function, as the structures aren't created yet.             */
2340 
2341 	pnum = port->number - serial->minor;
2342 
2343 	dev_dbg(&port->dev, "mos7840_startup: configuring port %d\n", pnum);
2344 	mos7840_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2345 	if (mos7840_port == NULL) {
2346 		dev_err(&port->dev, "%s - Out of memory\n", __func__);
2347 		return -ENOMEM;
2348 	}
2349 
2350 	/* Initialize all port interrupt end point to port 0 int
2351 	 * endpoint. Our device has only one interrupt end point
2352 	 * common to all port */
2353 
2354 	mos7840_port->port = port;
2355 	mos7840_set_port_private(port, mos7840_port);
2356 	spin_lock_init(&mos7840_port->pool_lock);
2357 
2358 	/* minor is not initialised until later by
2359 	 * usb-serial.c:get_free_serial() and cannot therefore be used
2360 	 * to index device instances */
2361 	mos7840_port->port_num = pnum + 1;
2362 	dev_dbg(&port->dev, "port->number = %d\n", port->number);
2363 	dev_dbg(&port->dev, "port->serial->minor = %d\n", port->serial->minor);
2364 	dev_dbg(&port->dev, "mos7840_port->port_num = %d\n", mos7840_port->port_num);
2365 	dev_dbg(&port->dev, "serial->minor = %d\n", serial->minor);
2366 
2367 	if (mos7840_port->port_num == 1) {
2368 		mos7840_port->SpRegOffset = 0x0;
2369 		mos7840_port->ControlRegOffset = 0x1;
2370 		mos7840_port->DcrRegOffset = 0x4;
2371 	} else if ((mos7840_port->port_num == 2) && (serial->num_ports == 4)) {
2372 		mos7840_port->SpRegOffset = 0x8;
2373 		mos7840_port->ControlRegOffset = 0x9;
2374 		mos7840_port->DcrRegOffset = 0x16;
2375 	} else if ((mos7840_port->port_num == 2) && (serial->num_ports == 2)) {
2376 		mos7840_port->SpRegOffset = 0xa;
2377 		mos7840_port->ControlRegOffset = 0xb;
2378 		mos7840_port->DcrRegOffset = 0x19;
2379 	} else if ((mos7840_port->port_num == 3) && (serial->num_ports == 4)) {
2380 		mos7840_port->SpRegOffset = 0xa;
2381 		mos7840_port->ControlRegOffset = 0xb;
2382 		mos7840_port->DcrRegOffset = 0x19;
2383 	} else if ((mos7840_port->port_num == 4) && (serial->num_ports == 4)) {
2384 		mos7840_port->SpRegOffset = 0xc;
2385 		mos7840_port->ControlRegOffset = 0xd;
2386 		mos7840_port->DcrRegOffset = 0x1c;
2387 	}
2388 	mos7840_dump_serial_port(port, mos7840_port);
2389 	mos7840_set_port_private(port, mos7840_port);
2390 
2391 	/* enable rx_disable bit in control register */
2392 	status = mos7840_get_reg_sync(port,
2393 			mos7840_port->ControlRegOffset, &Data);
2394 	if (status < 0) {
2395 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
2396 		goto out;
2397 	} else
2398 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
2399 	Data |= 0x08;	/* setting driver done bit */
2400 	Data |= 0x04;	/* sp1_bit to have cts change reflect in
2401 			   modem status reg */
2402 
2403 	/* Data |= 0x20; //rx_disable bit */
2404 	status = mos7840_set_reg_sync(port,
2405 			mos7840_port->ControlRegOffset, Data);
2406 	if (status < 0) {
2407 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
2408 		goto out;
2409 	} else
2410 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
2411 
2412 	/* Write default values in DCR (i.e 0x01 in DCR0, 0x05 in DCR2
2413 	   and 0x24 in DCR3 */
2414 	Data = 0x01;
2415 	status = mos7840_set_reg_sync(port,
2416 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
2417 	if (status < 0) {
2418 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
2419 		goto out;
2420 	} else
2421 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
2422 
2423 	Data = 0x05;
2424 	status = mos7840_set_reg_sync(port,
2425 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
2426 	if (status < 0) {
2427 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
2428 		goto out;
2429 	} else
2430 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
2431 
2432 	Data = 0x24;
2433 	status = mos7840_set_reg_sync(port,
2434 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
2435 	if (status < 0) {
2436 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
2437 		goto out;
2438 	} else
2439 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
2440 
2441 	/* write values in clkstart0x0 and clkmulti 0x20 */
2442 	Data = 0x0;
2443 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
2444 	if (status < 0) {
2445 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
2446 		goto out;
2447 	} else
2448 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
2449 
2450 	Data = 0x20;
2451 	status = mos7840_set_reg_sync(port, CLK_MULTI_REGISTER, Data);
2452 	if (status < 0) {
2453 		dev_dbg(&port->dev, "Writing CLK_MULTI_REGISTER failed status-0x%x\n", status);
2454 		goto error;
2455 	} else
2456 		dev_dbg(&port->dev, "CLK_MULTI_REGISTER Writing success status%d\n", status);
2457 
2458 	/* write value 0x0 to scratchpad register */
2459 	Data = 0x00;
2460 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
2461 	if (status < 0) {
2462 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
2463 		goto out;
2464 	} else
2465 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
2466 
2467 	/* Zero Length flag register */
2468 	if ((mos7840_port->port_num != 1) && (serial->num_ports == 2)) {
2469 		Data = 0xff;
2470 		status = mos7840_set_reg_sync(port,
2471 				(__u16) (ZLP_REG1 +
2472 					((__u16)mos7840_port->port_num)), Data);
2473 		dev_dbg(&port->dev, "ZLIP offset %x\n",
2474 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
2475 		if (status < 0) {
2476 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
2477 			goto out;
2478 		} else
2479 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
2480 	} else {
2481 		Data = 0xff;
2482 		status = mos7840_set_reg_sync(port,
2483 				(__u16) (ZLP_REG1 +
2484 					((__u16)mos7840_port->port_num) - 0x1), Data);
2485 		dev_dbg(&port->dev, "ZLIP offset %x\n",
2486 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
2487 		if (status < 0) {
2488 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
2489 			goto out;
2490 		} else
2491 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
2492 
2493 	}
2494 	mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
2495 	mos7840_port->ctrl_buf = kmalloc(16, GFP_KERNEL);
2496 	mos7840_port->dr = kmalloc(sizeof(struct usb_ctrlrequest),
2497 			GFP_KERNEL);
2498 	if (!mos7840_port->control_urb || !mos7840_port->ctrl_buf ||
2499 			!mos7840_port->dr) {
2500 		status = -ENOMEM;
2501 		goto error;
2502 	}
2503 
2504 	mos7840_port->has_led = false;
2505 
2506 	/* Initialize LED timers */
2507 	if (device_type == MOSCHIP_DEVICE_ID_7810) {
2508 		mos7840_port->has_led = true;
2509 
2510 		init_timer(&mos7840_port->led_timer1);
2511 		mos7840_port->led_timer1.function = mos7840_led_off;
2512 		mos7840_port->led_timer1.expires =
2513 			jiffies + msecs_to_jiffies(LED_ON_MS);
2514 		mos7840_port->led_timer1.data = (unsigned long)mos7840_port;
2515 
2516 		init_timer(&mos7840_port->led_timer2);
2517 		mos7840_port->led_timer2.function = mos7840_led_flag_off;
2518 		mos7840_port->led_timer2.expires =
2519 			jiffies + msecs_to_jiffies(LED_OFF_MS);
2520 		mos7840_port->led_timer2.data = (unsigned long)mos7840_port;
2521 
2522 		mos7840_port->led_flag = false;
2523 
2524 		/* Turn off LED */
2525 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
2526 	}
2527 out:
2528 	if (pnum == serial->num_ports - 1) {
2529 		/* Zero Length flag enable */
2530 		Data = 0x0f;
2531 		status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
2532 		if (status < 0) {
2533 			dev_dbg(&port->dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
2534 			goto error;
2535 		} else
2536 			dev_dbg(&port->dev, "ZLP_REG5 Writing success status%d\n", status);
2537 
2538 		/* setting configuration feature to one */
2539 		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2540 				0x03, 0x00, 0x01, 0x00, NULL, 0x00,
2541 				MOS_WDR_TIMEOUT);
2542 	}
2543 	return 0;
2544 error:
2545 	kfree(mos7840_port->dr);
2546 	kfree(mos7840_port->ctrl_buf);
2547 	usb_free_urb(mos7840_port->control_urb);
2548 	kfree(mos7840_port);
2549 
2550 	return status;
2551 }
2552 
2553 static int mos7840_port_remove(struct usb_serial_port *port)
2554 {
2555 	struct moschip_port *mos7840_port;
2556 
2557 	mos7840_port = mos7840_get_port_private(port);
2558 
2559 	if (mos7840_port->has_led) {
2560 		/* Turn off LED */
2561 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
2562 
2563 		del_timer_sync(&mos7840_port->led_timer1);
2564 		del_timer_sync(&mos7840_port->led_timer2);
2565 	}
2566 	usb_kill_urb(mos7840_port->control_urb);
2567 	usb_free_urb(mos7840_port->control_urb);
2568 	kfree(mos7840_port->ctrl_buf);
2569 	kfree(mos7840_port->dr);
2570 	kfree(mos7840_port);
2571 
2572 	return 0;
2573 }
2574 
2575 static struct usb_serial_driver moschip7840_4port_device = {
2576 	.driver = {
2577 		   .owner = THIS_MODULE,
2578 		   .name = "mos7840",
2579 		   },
2580 	.description = DRIVER_DESC,
2581 	.id_table = id_table,
2582 	.num_ports = 4,
2583 	.open = mos7840_open,
2584 	.close = mos7840_close,
2585 	.write = mos7840_write,
2586 	.write_room = mos7840_write_room,
2587 	.chars_in_buffer = mos7840_chars_in_buffer,
2588 	.throttle = mos7840_throttle,
2589 	.unthrottle = mos7840_unthrottle,
2590 	.calc_num_ports = mos7840_calc_num_ports,
2591 #ifdef MCSSerialProbe
2592 	.probe = mos7840_serial_probe,
2593 #endif
2594 	.ioctl = mos7840_ioctl,
2595 	.set_termios = mos7840_set_termios,
2596 	.break_ctl = mos7840_break,
2597 	.tiocmget = mos7840_tiocmget,
2598 	.tiocmset = mos7840_tiocmset,
2599 	.get_icount = mos7840_get_icount,
2600 	.port_probe = mos7840_port_probe,
2601 	.port_remove = mos7840_port_remove,
2602 	.read_bulk_callback = mos7840_bulk_in_callback,
2603 	.read_int_callback = mos7840_interrupt_callback,
2604 };
2605 
2606 static struct usb_serial_driver * const serial_drivers[] = {
2607 	&moschip7840_4port_device, NULL
2608 };
2609 
2610 module_usb_serial_driver(serial_drivers, id_table);
2611 
2612 MODULE_DESCRIPTION(DRIVER_DESC);
2613 MODULE_LICENSE("GPL");
2614