xref: /linux/drivers/usb/serial/ti_usb_3410_5052.c (revision 776cfebb430c7b22c208b1b17add97f354d97cab)
1 /* vi: ts=8 sw=8
2  *
3  * TI 3410/5052 USB Serial Driver
4  *
5  * Copyright (C) 2004 Texas Instruments
6  *
7  * This driver is based on the Linux io_ti driver, which is
8  *   Copyright (C) 2000-2002 Inside Out Networks
9  *   Copyright (C) 2001-2002 Greg Kroah-Hartman
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * For questions or problems with this driver, contact Texas Instruments
17  * technical support, or Al Borchers <alborchers@steinerpoint.com>, or
18  * Peter Berger <pberger@brimson.com>.
19  *
20  * This driver needs this hotplug script in /etc/hotplug/usb/ti_usb_3410_5052
21  * or in /etc/hotplug.d/usb/ti_usb_3410_5052.hotplug to set the device
22  * configuration.
23  *
24  * #!/bin/bash
25  *
26  * BOOT_CONFIG=1
27  * ACTIVE_CONFIG=2
28  *
29  * if [[ "$ACTION" != "add" ]]
30  * then
31  * 	exit
32  * fi
33  *
34  * CONFIG_PATH=/sys${DEVPATH%/?*}/bConfigurationValue
35  *
36  * if [[ 0`cat $CONFIG_PATH` -ne $BOOT_CONFIG ]]
37  * then
38  * 	exit
39  * fi
40  *
41  * PRODUCT=${PRODUCT%/?*}		# delete version
42  * VENDOR_ID=`printf "%d" 0x${PRODUCT%/?*}`
43  * PRODUCT_ID=`printf "%d" 0x${PRODUCT#*?/}`
44  *
45  * PARAM_PATH=/sys/module/ti_usb_3410_5052/parameters
46  *
47  * function scan() {
48  * 	s=$1
49  * 	shift
50  * 	for i
51  * 	do
52  * 		if [[ $s -eq $i ]]
53  * 		then
54  * 			return 0
55  * 		fi
56  * 	done
57  * 	return 1
58  * }
59  *
60  * IFS=$IFS,
61  *
62  * if (scan $VENDOR_ID 1105 `cat $PARAM_PATH/vendor_3410` &&
63  * scan $PRODUCT_ID 13328 `cat $PARAM_PATH/product_3410`) ||
64  * (scan $VENDOR_ID 1105 `cat $PARAM_PATH/vendor_5052` &&
65  * scan $PRODUCT_ID 20562 20818 20570 20575 `cat $PARAM_PATH/product_5052`)
66  * then
67  * 	echo $ACTIVE_CONFIG > $CONFIG_PATH
68  * fi
69  */
70 
71 #include <linux/config.h>
72 #include <linux/kernel.h>
73 #include <linux/errno.h>
74 #include <linux/init.h>
75 #include <linux/slab.h>
76 #include <linux/tty.h>
77 #include <linux/tty_driver.h>
78 #include <linux/tty_flip.h>
79 #include <linux/module.h>
80 #include <linux/spinlock.h>
81 #include <linux/ioctl.h>
82 #include <linux/serial.h>
83 #include <linux/circ_buf.h>
84 #include <asm/uaccess.h>
85 #include <asm/semaphore.h>
86 #include <linux/usb.h>
87 
88 #include "usb-serial.h"
89 #include "ti_usb_3410_5052.h"
90 #include "ti_fw_3410.h"		/* firmware image for 3410 */
91 #include "ti_fw_5052.h"		/* firmware image for 5052 */
92 
93 
94 /* Defines */
95 
96 #define TI_DRIVER_VERSION	"v0.9"
97 #define TI_DRIVER_AUTHOR	"Al Borchers <alborchers@steinerpoint.com>"
98 #define TI_DRIVER_DESC		"TI USB 3410/5052 Serial Driver"
99 
100 #define TI_FIRMWARE_BUF_SIZE	16284
101 
102 #define TI_WRITE_BUF_SIZE	1024
103 
104 #define TI_TRANSFER_TIMEOUT	2
105 
106 #define TI_DEFAULT_LOW_LATENCY	0
107 #define TI_DEFAULT_CLOSING_WAIT	4000		/* in .01 secs */
108 
109 /* supported setserial flags */
110 #define TI_SET_SERIAL_FLAGS	(ASYNC_LOW_LATENCY)
111 
112 /* read urb states */
113 #define TI_READ_URB_RUNNING	0
114 #define TI_READ_URB_STOPPING	1
115 #define TI_READ_URB_STOPPED	2
116 
117 #define TI_EXTRA_VID_PID_COUNT	5
118 
119 
120 /* Structures */
121 
122 struct ti_port {
123 	int			tp_is_open;
124 	__u8			tp_msr;
125 	__u8			tp_lsr;
126 	__u8			tp_shadow_mcr;
127 	__u8			tp_uart_mode;	/* 232 or 485 modes */
128 	unsigned int		tp_uart_base_addr;
129 	int			tp_flags;
130 	int			tp_closing_wait;/* in .01 secs */
131 	struct async_icount	tp_icount;
132 	wait_queue_head_t	tp_msr_wait;	/* wait for msr change */
133 	wait_queue_head_t	tp_write_wait;
134 	struct ti_device	*tp_tdev;
135 	struct usb_serial_port	*tp_port;
136 	spinlock_t		tp_lock;
137 	int			tp_read_urb_state;
138 	int			tp_write_urb_in_use;
139 	struct circ_buf		*tp_write_buf;
140 };
141 
142 struct ti_device {
143 	struct semaphore	td_open_close_sem;
144 	int			td_open_port_count;
145 	struct usb_serial	*td_serial;
146 	int			td_is_3410;
147 	int			td_urb_error;
148 };
149 
150 
151 /* Function Declarations */
152 
153 static int ti_startup(struct usb_serial *serial);
154 static void ti_shutdown(struct usb_serial *serial);
155 static int ti_open(struct usb_serial_port *port, struct file *file);
156 static void ti_close(struct usb_serial_port *port, struct file *file);
157 static int ti_write(struct usb_serial_port *port, const unsigned char *data,
158 	int count);
159 static int ti_write_room(struct usb_serial_port *port);
160 static int ti_chars_in_buffer(struct usb_serial_port *port);
161 static void ti_throttle(struct usb_serial_port *port);
162 static void ti_unthrottle(struct usb_serial_port *port);
163 static int ti_ioctl(struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg);
164 static void ti_set_termios(struct usb_serial_port *port,
165 	struct termios *old_termios);
166 static int ti_tiocmget(struct usb_serial_port *port, struct file *file);
167 static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
168 	unsigned int set, unsigned int clear);
169 static void ti_break(struct usb_serial_port *port, int break_state);
170 static void ti_interrupt_callback(struct urb *urb, struct pt_regs *regs);
171 static void ti_bulk_in_callback(struct urb *urb, struct pt_regs *regs);
172 static void ti_bulk_out_callback(struct urb *urb, struct pt_regs *regs);
173 
174 static void ti_recv(struct device *dev, struct tty_struct *tty,
175 	unsigned char *data, int length);
176 static void ti_send(struct ti_port *tport);
177 static int ti_set_mcr(struct ti_port *tport, unsigned int mcr);
178 static int ti_get_lsr(struct ti_port *tport);
179 static int ti_get_serial_info(struct ti_port *tport,
180 	struct serial_struct __user *ret_arg);
181 static int ti_set_serial_info(struct ti_port *tport,
182 	struct serial_struct __user *new_arg);
183 static void ti_handle_new_msr(struct ti_port *tport, __u8 msr);
184 
185 static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush);
186 
187 static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty);
188 static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty);
189 
190 static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
191 	__u16 moduleid, __u16 value, __u8 *data, int size);
192 static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
193 	__u16 moduleid, __u16 value, __u8 *data, int size);
194 
195 static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
196 	__u8 mask, __u8 byte);
197 
198 static int ti_download_firmware(struct ti_device *tdev,
199 	unsigned char *firmware, unsigned int firmware_size);
200 
201 /* circular buffer */
202 static struct circ_buf *ti_buf_alloc(void);
203 static void ti_buf_free(struct circ_buf *cb);
204 static void ti_buf_clear(struct circ_buf *cb);
205 static int ti_buf_data_avail(struct circ_buf *cb);
206 static int ti_buf_space_avail(struct circ_buf *cb);
207 static int ti_buf_put(struct circ_buf *cb, const char *buf, int count);
208 static int ti_buf_get(struct circ_buf *cb, char *buf, int count);
209 
210 
211 /* Data */
212 
213 /* module parameters */
214 static int debug;
215 static int low_latency = TI_DEFAULT_LOW_LATENCY;
216 static int closing_wait = TI_DEFAULT_CLOSING_WAIT;
217 static ushort vendor_3410[TI_EXTRA_VID_PID_COUNT];
218 static int vendor_3410_count;
219 static ushort product_3410[TI_EXTRA_VID_PID_COUNT];
220 static int product_3410_count;
221 static ushort vendor_5052[TI_EXTRA_VID_PID_COUNT];
222 static int vendor_5052_count;
223 static ushort product_5052[TI_EXTRA_VID_PID_COUNT];
224 static int product_5052_count;
225 
226 /* supported devices */
227 /* the array dimension is the number of default entries plus */
228 /* TI_EXTRA_VID_PID_COUNT user defined entries plus 1 terminating */
229 /* null entry */
230 static struct usb_device_id ti_id_table_3410[1+TI_EXTRA_VID_PID_COUNT+1] = {
231 	{ USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
232 };
233 
234 static struct usb_device_id ti_id_table_5052[4+TI_EXTRA_VID_PID_COUNT+1] = {
235 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
236 	{ USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
237 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
238 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
239 };
240 
241 static struct usb_device_id ti_id_table_combined[] = {
242 	{ USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
243 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
244 	{ USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
245 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
246 	{ USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
247 	{ }
248 };
249 
250 static struct usb_driver ti_usb_driver = {
251 	.owner			= THIS_MODULE,
252 	.name			= "ti_usb_3410_5052",
253 	.probe			= usb_serial_probe,
254 	.disconnect		= usb_serial_disconnect,
255 	.id_table		= ti_id_table_combined,
256 };
257 
258 static struct usb_serial_device_type ti_1port_device = {
259 	.owner			= THIS_MODULE,
260 	.name			= "TI USB 3410 1 port adapter",
261 	.id_table		= ti_id_table_3410,
262 	.num_interrupt_in	= 1,
263 	.num_bulk_in		= 1,
264 	.num_bulk_out		= 1,
265 	.num_ports		= 1,
266 	.attach			= ti_startup,
267 	.shutdown		= ti_shutdown,
268 	.open			= ti_open,
269 	.close			= ti_close,
270 	.write			= ti_write,
271 	.write_room		= ti_write_room,
272 	.chars_in_buffer	= ti_chars_in_buffer,
273 	.throttle		= ti_throttle,
274 	.unthrottle		= ti_unthrottle,
275 	.ioctl			= ti_ioctl,
276 	.set_termios		= ti_set_termios,
277 	.tiocmget		= ti_tiocmget,
278 	.tiocmset		= ti_tiocmset,
279 	.break_ctl		= ti_break,
280 	.read_int_callback	= ti_interrupt_callback,
281 	.read_bulk_callback	= ti_bulk_in_callback,
282 	.write_bulk_callback	= ti_bulk_out_callback,
283 };
284 
285 static struct usb_serial_device_type ti_2port_device = {
286 	.owner			= THIS_MODULE,
287 	.name			= "TI USB 5052 2 port adapter",
288 	.id_table		= ti_id_table_5052,
289 	.num_interrupt_in	= 1,
290 	.num_bulk_in		= 2,
291 	.num_bulk_out		= 2,
292 	.num_ports		= 2,
293 	.attach			= ti_startup,
294 	.shutdown		= ti_shutdown,
295 	.open			= ti_open,
296 	.close			= ti_close,
297 	.write			= ti_write,
298 	.write_room		= ti_write_room,
299 	.chars_in_buffer	= ti_chars_in_buffer,
300 	.throttle		= ti_throttle,
301 	.unthrottle		= ti_unthrottle,
302 	.ioctl			= ti_ioctl,
303 	.set_termios		= ti_set_termios,
304 	.tiocmget		= ti_tiocmget,
305 	.tiocmset		= ti_tiocmset,
306 	.break_ctl		= ti_break,
307 	.read_int_callback	= ti_interrupt_callback,
308 	.read_bulk_callback	= ti_bulk_in_callback,
309 	.write_bulk_callback	= ti_bulk_out_callback,
310 };
311 
312 
313 /* Module */
314 
315 MODULE_AUTHOR(TI_DRIVER_AUTHOR);
316 MODULE_DESCRIPTION(TI_DRIVER_DESC);
317 MODULE_VERSION(TI_DRIVER_VERSION);
318 MODULE_LICENSE("GPL");
319 
320 module_param(debug, bool, S_IRUGO | S_IWUSR);
321 MODULE_PARM_DESC(debug, "Enable debugging, 0=no, 1=yes");
322 
323 module_param(low_latency, bool, S_IRUGO | S_IWUSR);
324 MODULE_PARM_DESC(low_latency, "TTY low_latency flag, 0=off, 1=on, default is off");
325 
326 module_param(closing_wait, int, S_IRUGO | S_IWUSR);
327 MODULE_PARM_DESC(closing_wait, "Maximum wait for data to drain in close, in .01 secs, default is 4000");
328 
329 module_param_array(vendor_3410, ushort, &vendor_3410_count, S_IRUGO);
330 MODULE_PARM_DESC(vendor_3410, "Vendor ids for 3410 based devices, 1-5 short integers");
331 module_param_array(product_3410, ushort, &product_3410_count, S_IRUGO);
332 MODULE_PARM_DESC(product_3410, "Product ids for 3410 based devices, 1-5 short integers");
333 module_param_array(vendor_5052, ushort, &vendor_5052_count, S_IRUGO);
334 MODULE_PARM_DESC(vendor_5052, "Vendor ids for 5052 based devices, 1-5 short integers");
335 module_param_array(product_5052, ushort, &product_5052_count, S_IRUGO);
336 MODULE_PARM_DESC(product_5052, "Product ids for 5052 based devices, 1-5 short integers");
337 
338 MODULE_DEVICE_TABLE(usb, ti_id_table_combined);
339 
340 
341 /* Functions */
342 
343 static int __init ti_init(void)
344 {
345 	int i,j;
346 	int ret;
347 
348 
349 	/* insert extra vendor and product ids */
350 	j = sizeof(ti_id_table_3410)/sizeof(struct usb_device_id)
351 		- TI_EXTRA_VID_PID_COUNT - 1;
352 	for (i=0; i<min(vendor_3410_count,product_3410_count); i++,j++) {
353 		ti_id_table_3410[j].idVendor = vendor_3410[i];
354 		ti_id_table_3410[j].idProduct = product_3410[i];
355 		ti_id_table_3410[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
356 	}
357 	j = sizeof(ti_id_table_5052)/sizeof(struct usb_device_id)
358 		- TI_EXTRA_VID_PID_COUNT - 1;
359 	for (i=0; i<min(vendor_5052_count,product_5052_count); i++,j++) {
360 		ti_id_table_5052[j].idVendor = vendor_5052[i];
361 		ti_id_table_5052[j].idProduct = product_5052[i];
362 		ti_id_table_5052[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
363 	}
364 
365 	ret = usb_serial_register(&ti_1port_device);
366 	if (ret)
367 		goto failed_1port;
368 	ret = usb_serial_register(&ti_2port_device);
369 	if (ret)
370 		goto failed_2port;
371 
372 	ret = usb_register(&ti_usb_driver);
373 	if (ret)
374 		goto failed_usb;
375 
376 	info(TI_DRIVER_DESC " " TI_DRIVER_VERSION);
377 
378 	return 0;
379 
380 failed_usb:
381 	usb_serial_deregister(&ti_2port_device);
382 failed_2port:
383 	usb_serial_deregister(&ti_1port_device);
384 failed_1port:
385 	return ret;
386 }
387 
388 
389 static void __exit ti_exit(void)
390 {
391 	usb_serial_deregister(&ti_1port_device);
392 	usb_serial_deregister(&ti_2port_device);
393 	usb_deregister(&ti_usb_driver);
394 }
395 
396 
397 module_init(ti_init);
398 module_exit(ti_exit);
399 
400 
401 static int ti_startup(struct usb_serial *serial)
402 {
403 	struct ti_device *tdev;
404 	struct ti_port *tport;
405 	struct usb_device *dev = serial->dev;
406 	int status;
407 	int i;
408 
409 
410 	dbg("%s - product 0x%4X, num configurations %d, configuration value %d",
411 	    __FUNCTION__, le16_to_cpu(dev->descriptor.idProduct),
412 	    dev->descriptor.bNumConfigurations,
413 	    dev->actconfig->desc.bConfigurationValue);
414 
415 	/* create device structure */
416 	tdev = kmalloc(sizeof(struct ti_device), GFP_KERNEL);
417 	if (tdev == NULL) {
418 		dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
419 		return -ENOMEM;
420 	}
421 	memset(tdev, 0, sizeof(struct ti_device));
422 	sema_init(&tdev->td_open_close_sem, 1);
423 	tdev->td_serial = serial;
424 	usb_set_serial_data(serial, tdev);
425 
426 	/* determine device type */
427 	if (usb_match_id(serial->interface, ti_id_table_3410))
428 		tdev->td_is_3410 = 1;
429 	dbg("%s - device type is %s", __FUNCTION__, tdev->td_is_3410 ? "3410" : "5052");
430 
431 	/* if we have only 1 configuration, download firmware */
432 	if (dev->descriptor.bNumConfigurations == 1) {
433 
434 		if (tdev->td_is_3410)
435 			status = ti_download_firmware(tdev, ti_fw_3410,
436 				sizeof(ti_fw_3410));
437 		else
438 			status = ti_download_firmware(tdev, ti_fw_5052,
439 				sizeof(ti_fw_5052));
440 		if (status)
441 			goto free_tdev;
442 
443 		/* 3410 must be reset, 5052 resets itself */
444 		if (tdev->td_is_3410) {
445 			msleep_interruptible(100);
446 			usb_reset_device(dev);
447 		}
448 
449 		status = -ENODEV;
450 		goto free_tdev;
451 	}
452 
453 	/* the second configuration must be set (in sysfs by hotplug script) */
454 	if (dev->actconfig->desc.bConfigurationValue == TI_BOOT_CONFIG) {
455 		status = -ENODEV;
456 		goto free_tdev;
457 	}
458 
459 	/* set up port structures */
460 	for (i = 0; i < serial->num_ports; ++i) {
461 		tport = kmalloc(sizeof(struct ti_port), GFP_KERNEL);
462 		if (tport == NULL) {
463 			dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
464 			status = -ENOMEM;
465 			goto free_tports;
466 		}
467 		memset(tport, 0, sizeof(struct ti_port));
468 		spin_lock_init(&tport->tp_lock);
469 		tport->tp_uart_base_addr = (i == 0 ? TI_UART1_BASE_ADDR : TI_UART2_BASE_ADDR);
470 		tport->tp_flags = low_latency ? ASYNC_LOW_LATENCY : 0;
471 		tport->tp_closing_wait = closing_wait;
472 		init_waitqueue_head(&tport->tp_msr_wait);
473 		init_waitqueue_head(&tport->tp_write_wait);
474 		tport->tp_write_buf = ti_buf_alloc();
475 		if (tport->tp_write_buf == NULL) {
476 			dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
477 			kfree(tport);
478 			status = -ENOMEM;
479 			goto free_tports;
480 		}
481 		tport->tp_port = serial->port[i];
482 		tport->tp_tdev = tdev;
483 		usb_set_serial_port_data(serial->port[i], tport);
484 		tport->tp_uart_mode = 0;	/* default is RS232 */
485 	}
486 
487 	return 0;
488 
489 free_tports:
490 	for (--i; i>=0; --i) {
491 		tport = usb_get_serial_port_data(serial->port[i]);
492 		ti_buf_free(tport->tp_write_buf);
493 		kfree(tport);
494 		usb_set_serial_port_data(serial->port[i], NULL);
495 	}
496 free_tdev:
497 	kfree(tdev);
498 	usb_set_serial_data(serial, NULL);
499 	return status;
500 }
501 
502 
503 static void ti_shutdown(struct usb_serial *serial)
504 {
505 	int i;
506 	struct ti_device *tdev = usb_get_serial_data(serial);
507 	struct ti_port *tport;
508 
509 	dbg("%s", __FUNCTION__);
510 
511 	for (i=0; i < serial->num_ports; ++i) {
512 		tport = usb_get_serial_port_data(serial->port[i]);
513 		if (tport) {
514 			ti_buf_free(tport->tp_write_buf);
515 			kfree(tport);
516 			usb_set_serial_port_data(serial->port[i], NULL);
517 		}
518 	}
519 
520 	kfree(tdev);
521 	usb_set_serial_data(serial, NULL);
522 }
523 
524 
525 static int ti_open(struct usb_serial_port *port, struct file *file)
526 {
527 	struct ti_port *tport = usb_get_serial_port_data(port);
528 	struct ti_device *tdev;
529 	struct usb_device *dev;
530 	struct urb *urb;
531 	int port_number;
532 	int status;
533 	__u16 open_settings = (__u8)(TI_PIPE_MODE_CONTINOUS |
534 			     TI_PIPE_TIMEOUT_ENABLE |
535 			     (TI_TRANSFER_TIMEOUT << 2));
536 
537 	dbg("%s - port %d", __FUNCTION__, port->number);
538 
539 	if (tport == NULL)
540 		return -ENODEV;
541 
542 	dev = port->serial->dev;
543 	tdev = tport->tp_tdev;
544 
545 	/* only one open on any port on a device at a time */
546 	if (down_interruptible(&tdev->td_open_close_sem))
547 		return -ERESTARTSYS;
548 
549 	if (port->tty)
550 		port->tty->low_latency =
551 			(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
552 
553 	port_number = port->number - port->serial->minor;
554 
555 	memset(&(tport->tp_icount), 0x00, sizeof(tport->tp_icount));
556 
557 	tport->tp_msr = 0;
558 	tport->tp_shadow_mcr |= (TI_MCR_RTS | TI_MCR_DTR);
559 
560 	/* start interrupt urb the first time a port is opened on this device */
561 	if (tdev->td_open_port_count == 0) {
562 		dbg("%s - start interrupt in urb", __FUNCTION__);
563 		urb = tdev->td_serial->port[0]->interrupt_in_urb;
564 		if (!urb) {
565 			dev_err(&port->dev, "%s - no interrupt urb\n", __FUNCTION__);
566 			status = -EINVAL;
567 			goto up_sem;
568 		}
569 		urb->complete = ti_interrupt_callback;
570 		urb->context = tdev;
571 		urb->dev = dev;
572 		status = usb_submit_urb(urb, GFP_KERNEL);
573 		if (status) {
574 			dev_err(&port->dev, "%s - submit interrupt urb failed, %d\n", __FUNCTION__, status);
575 			goto up_sem;
576 		}
577 	}
578 
579 	ti_set_termios(port, NULL);
580 
581 	dbg("%s - sending TI_OPEN_PORT", __FUNCTION__);
582 	status = ti_command_out_sync(tdev, TI_OPEN_PORT,
583 		(__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
584 	if (status) {
585 		dev_err(&port->dev, "%s - cannot send open command, %d\n", __FUNCTION__, status);
586 		goto unlink_int_urb;
587 	}
588 
589 	dbg("%s - sending TI_START_PORT", __FUNCTION__);
590 	status = ti_command_out_sync(tdev, TI_START_PORT,
591 		(__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
592 	if (status) {
593 		dev_err(&port->dev, "%s - cannot send start command, %d\n", __FUNCTION__, status);
594 		goto unlink_int_urb;
595 	}
596 
597 	dbg("%s - sending TI_PURGE_PORT", __FUNCTION__);
598 	status = ti_command_out_sync(tdev, TI_PURGE_PORT,
599 		(__u8)(TI_UART1_PORT + port_number), TI_PURGE_INPUT, NULL, 0);
600 	if (status) {
601 		dev_err(&port->dev, "%s - cannot clear input buffers, %d\n", __FUNCTION__, status);
602 		goto unlink_int_urb;
603 	}
604 	status = ti_command_out_sync(tdev, TI_PURGE_PORT,
605 		(__u8)(TI_UART1_PORT + port_number), TI_PURGE_OUTPUT, NULL, 0);
606 	if (status) {
607 		dev_err(&port->dev, "%s - cannot clear output buffers, %d\n", __FUNCTION__, status);
608 		goto unlink_int_urb;
609 	}
610 
611 	/* reset the data toggle on the bulk endpoints to work around bug in
612 	 * host controllers where things get out of sync some times */
613 	usb_clear_halt(dev, port->write_urb->pipe);
614 	usb_clear_halt(dev, port->read_urb->pipe);
615 
616 	ti_set_termios(port, NULL);
617 
618 	dbg("%s - sending TI_OPEN_PORT (2)", __FUNCTION__);
619 	status = ti_command_out_sync(tdev, TI_OPEN_PORT,
620 		(__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
621 	if (status) {
622 		dev_err(&port->dev, "%s - cannot send open command (2), %d\n", __FUNCTION__, status);
623 		goto unlink_int_urb;
624 	}
625 
626 	dbg("%s - sending TI_START_PORT (2)", __FUNCTION__);
627 	status = ti_command_out_sync(tdev, TI_START_PORT,
628 		(__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
629 	if (status) {
630 		dev_err(&port->dev, "%s - cannot send start command (2), %d\n", __FUNCTION__, status);
631 		goto unlink_int_urb;
632 	}
633 
634 	/* start read urb */
635 	dbg("%s - start read urb", __FUNCTION__);
636 	urb = port->read_urb;
637 	if (!urb) {
638 		dev_err(&port->dev, "%s - no read urb\n", __FUNCTION__);
639 		status = -EINVAL;
640 		goto unlink_int_urb;
641 	}
642 	tport->tp_read_urb_state = TI_READ_URB_RUNNING;
643 	urb->complete = ti_bulk_in_callback;
644 	urb->context = tport;
645 	urb->dev = dev;
646 	status = usb_submit_urb(urb, GFP_KERNEL);
647 	if (status) {
648 		dev_err(&port->dev, "%s - submit read urb failed, %d\n", __FUNCTION__, status);
649 		goto unlink_int_urb;
650 	}
651 
652 	tport->tp_is_open = 1;
653 	++tdev->td_open_port_count;
654 
655 	goto up_sem;
656 
657 unlink_int_urb:
658 	if (tdev->td_open_port_count == 0)
659 		usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
660 up_sem:
661 	up(&tdev->td_open_close_sem);
662 	dbg("%s - exit %d", __FUNCTION__, status);
663 	return status;
664 }
665 
666 
667 static void ti_close(struct usb_serial_port *port, struct file *file)
668 {
669 	struct ti_device *tdev;
670 	struct ti_port *tport;
671 	int port_number;
672 	int status;
673 	int do_up;
674 
675 	dbg("%s - port %d", __FUNCTION__, port->number);
676 
677 	tdev = usb_get_serial_data(port->serial);
678 	tport = usb_get_serial_port_data(port);
679 	if (tdev == NULL || tport == NULL)
680 		return;
681 
682 	tport->tp_is_open = 0;
683 
684 	ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 1);
685 
686 	usb_kill_urb(port->read_urb);
687 	usb_kill_urb(port->write_urb);
688 	tport->tp_write_urb_in_use = 0;
689 
690 	port_number = port->number - port->serial->minor;
691 
692 	dbg("%s - sending TI_CLOSE_PORT", __FUNCTION__);
693 	status = ti_command_out_sync(tdev, TI_CLOSE_PORT,
694 		     (__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
695 	if (status)
696 		dev_err(&port->dev, "%s - cannot send close port command, %d\n" , __FUNCTION__, status);
697 
698 	/* if down is interrupted, continue anyway */
699 	do_up = !down_interruptible(&tdev->td_open_close_sem);
700 	--tport->tp_tdev->td_open_port_count;
701 	if (tport->tp_tdev->td_open_port_count <= 0) {
702 		/* last port is closed, shut down interrupt urb */
703 		usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
704 		tport->tp_tdev->td_open_port_count = 0;
705 	}
706 	if (do_up)
707 		up(&tdev->td_open_close_sem);
708 
709 	dbg("%s - exit", __FUNCTION__);
710 }
711 
712 
713 static int ti_write(struct usb_serial_port *port, const unsigned char *data,
714 	int count)
715 {
716 	struct ti_port *tport = usb_get_serial_port_data(port);
717 	unsigned long flags;
718 
719 	dbg("%s - port %d", __FUNCTION__, port->number);
720 
721 	if (count == 0) {
722 		dbg("%s - write request of 0 bytes", __FUNCTION__);
723 		return 0;
724 	}
725 
726 	if (tport == NULL || !tport->tp_is_open)
727 		return -ENODEV;
728 
729 	spin_lock_irqsave(&tport->tp_lock, flags);
730 	count = ti_buf_put(tport->tp_write_buf, data, count);
731 	spin_unlock_irqrestore(&tport->tp_lock, flags);
732 
733 	ti_send(tport);
734 
735 	return count;
736 }
737 
738 
739 static int ti_write_room(struct usb_serial_port *port)
740 {
741 	struct ti_port *tport = usb_get_serial_port_data(port);
742 	int room = 0;
743 	unsigned long flags;
744 
745 	dbg("%s - port %d", __FUNCTION__, port->number);
746 
747 	if (tport == NULL)
748 		return -ENODEV;
749 
750 	spin_lock_irqsave(&tport->tp_lock, flags);
751 	room = ti_buf_space_avail(tport->tp_write_buf);
752 	spin_unlock_irqrestore(&tport->tp_lock, flags);
753 
754 	dbg("%s - returns %d", __FUNCTION__, room);
755 	return room;
756 }
757 
758 
759 static int ti_chars_in_buffer(struct usb_serial_port *port)
760 {
761 	struct ti_port *tport = usb_get_serial_port_data(port);
762 	int chars = 0;
763 	unsigned long flags;
764 
765 	dbg("%s - port %d", __FUNCTION__, port->number);
766 
767 	if (tport == NULL)
768 		return -ENODEV;
769 
770 	spin_lock_irqsave(&tport->tp_lock, flags);
771 	chars = ti_buf_data_avail(tport->tp_write_buf);
772 	spin_unlock_irqrestore(&tport->tp_lock, flags);
773 
774 	dbg("%s - returns %d", __FUNCTION__, chars);
775 	return chars;
776 }
777 
778 
779 static void ti_throttle(struct usb_serial_port *port)
780 {
781 	struct ti_port *tport = usb_get_serial_port_data(port);
782 	struct tty_struct *tty;
783 
784 	dbg("%s - port %d", __FUNCTION__, port->number);
785 
786 	if (tport == NULL)
787 		return;
788 
789 	tty = port->tty;
790 	if (!tty) {
791 		dbg("%s - no tty", __FUNCTION__);
792 		return;
793 	}
794 
795 	if (I_IXOFF(tty) || C_CRTSCTS(tty))
796 		ti_stop_read(tport, tty);
797 
798 }
799 
800 
801 static void ti_unthrottle(struct usb_serial_port *port)
802 {
803 	struct ti_port *tport = usb_get_serial_port_data(port);
804 	struct tty_struct *tty;
805 	int status;
806 
807 	dbg("%s - port %d", __FUNCTION__, port->number);
808 
809 	if (tport == NULL)
810 		return;
811 
812 	tty = port->tty;
813 	if (!tty) {
814 		dbg("%s - no tty", __FUNCTION__);
815 		return;
816 	}
817 
818 	if (I_IXOFF(tty) || C_CRTSCTS(tty)) {
819 		status = ti_restart_read(tport, tty);
820 		if (status)
821 			dev_err(&port->dev, "%s - cannot restart read, %d\n", __FUNCTION__, status);
822 	}
823 }
824 
825 
826 static int ti_ioctl(struct usb_serial_port *port, struct file *file,
827 	unsigned int cmd, unsigned long arg)
828 {
829 	struct ti_port *tport = usb_get_serial_port_data(port);
830 	struct async_icount cnow;
831 	struct async_icount cprev;
832 
833 	dbg("%s - port %d, cmd = 0x%04X", __FUNCTION__, port->number, cmd);
834 
835 	if (tport == NULL)
836 		return -ENODEV;
837 
838 	switch (cmd) {
839 		case TIOCGSERIAL:
840 			dbg("%s - (%d) TIOCGSERIAL", __FUNCTION__, port->number);
841 			return ti_get_serial_info(tport, (struct serial_struct __user *)arg);
842 			break;
843 
844 		case TIOCSSERIAL:
845 			dbg("%s - (%d) TIOCSSERIAL", __FUNCTION__, port->number);
846 			return ti_set_serial_info(tport, (struct serial_struct __user *)arg);
847 			break;
848 
849 		case TIOCMIWAIT:
850 			dbg("%s - (%d) TIOCMIWAIT", __FUNCTION__, port->number);
851 			cprev = tport->tp_icount;
852 			while (1) {
853 				interruptible_sleep_on(&tport->tp_msr_wait);
854 				if (signal_pending(current))
855 					return -ERESTARTSYS;
856 				cnow = tport->tp_icount;
857 				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
858 				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
859 					return -EIO; /* no change => error */
860 				if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
861 				    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
862 				    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
863 				    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
864 					return 0;
865 				}
866 				cprev = cnow;
867 			}
868 			break;
869 
870 		case TIOCGICOUNT:
871 			dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d", __FUNCTION__, port->number, tport->tp_icount.rx, tport->tp_icount.tx);
872 			if (copy_to_user((void __user *)arg, &tport->tp_icount, sizeof(tport->tp_icount)))
873 				return -EFAULT;
874 			return 0;
875 	}
876 
877 	return -ENOIOCTLCMD;
878 }
879 
880 
881 static void ti_set_termios(struct usb_serial_port *port,
882 	struct termios *old_termios)
883 {
884 	struct ti_port *tport = usb_get_serial_port_data(port);
885 	struct tty_struct *tty = port->tty;
886 	struct ti_uart_config *config;
887 	tcflag_t cflag,iflag;
888 	int baud;
889 	int status;
890 	int port_number = port->number - port->serial->minor;
891 	unsigned int mcr;
892 
893 	dbg("%s - port %d", __FUNCTION__, port->number);
894 
895 	if (!tty || !tty->termios) {
896 		dbg("%s - no tty or termios", __FUNCTION__);
897 		return;
898 	}
899 
900 	cflag = tty->termios->c_cflag;
901 	iflag = tty->termios->c_iflag;
902 
903 	if (old_termios && cflag == old_termios->c_cflag
904 	&& iflag == old_termios->c_iflag) {
905 		dbg("%s - nothing to change", __FUNCTION__);
906 		return;
907 	}
908 
909 	dbg("%s - clfag %08x, iflag %08x", __FUNCTION__, cflag, iflag);
910 
911 	if (old_termios)
912 		dbg("%s - old clfag %08x, old iflag %08x", __FUNCTION__, old_termios->c_cflag, old_termios->c_iflag);
913 
914 	if (tport == NULL)
915 		return;
916 
917 	config = kmalloc(sizeof(*config), GFP_KERNEL);
918 	if (!config) {
919 		dev_err(&port->dev, "%s - out of memory\n", __FUNCTION__);
920 		return;
921 	}
922 
923 	config->wFlags = 0;
924 
925 	/* these flags must be set */
926 	config->wFlags |= TI_UART_ENABLE_MS_INTS;
927 	config->wFlags |= TI_UART_ENABLE_AUTO_START_DMA;
928 	config->bUartMode = (__u8)(tport->tp_uart_mode);
929 
930 	switch (cflag & CSIZE) {
931 		case CS5:
932 			    config->bDataBits = TI_UART_5_DATA_BITS;
933 			    break;
934 		case CS6:
935 			    config->bDataBits = TI_UART_6_DATA_BITS;
936 			    break;
937 		case CS7:
938 			    config->bDataBits = TI_UART_7_DATA_BITS;
939 			    break;
940 		default:
941 		case CS8:
942 			    config->bDataBits = TI_UART_8_DATA_BITS;
943 			    break;
944 	}
945 
946 	if (cflag & PARENB) {
947 		if (cflag & PARODD) {
948 			config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
949 			config->bParity = TI_UART_ODD_PARITY;
950 		} else {
951 			config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
952 			config->bParity = TI_UART_EVEN_PARITY;
953 		}
954 	} else {
955 		config->wFlags &= ~TI_UART_ENABLE_PARITY_CHECKING;
956 		config->bParity = TI_UART_NO_PARITY;
957 	}
958 
959 	if (cflag & CSTOPB)
960 		config->bStopBits = TI_UART_2_STOP_BITS;
961 	else
962 		config->bStopBits = TI_UART_1_STOP_BITS;
963 
964 	if (cflag & CRTSCTS) {
965 		/* RTS flow control must be off to drop RTS for baud rate B0 */
966 		if ((cflag & CBAUD) != B0)
967 			config->wFlags |= TI_UART_ENABLE_RTS_IN;
968 		config->wFlags |= TI_UART_ENABLE_CTS_OUT;
969 	} else {
970 		tty->hw_stopped = 0;
971 		ti_restart_read(tport, tty);
972 	}
973 
974 	if (I_IXOFF(tty) || I_IXON(tty)) {
975 		config->cXon  = START_CHAR(tty);
976 		config->cXoff = STOP_CHAR(tty);
977 
978 		if (I_IXOFF(tty))
979 			config->wFlags |= TI_UART_ENABLE_X_IN;
980 		else
981 			ti_restart_read(tport, tty);
982 
983 		if (I_IXON(tty))
984 			config->wFlags |= TI_UART_ENABLE_X_OUT;
985 	}
986 
987 	baud = tty_get_baud_rate(tty);
988 	if (!baud) baud = 9600;
989 	if (tport->tp_tdev->td_is_3410)
990 		config->wBaudRate = (__u16)((923077 + baud/2) / baud);
991 	else
992 		config->wBaudRate = (__u16)((461538 + baud/2) / baud);
993 
994 	dbg("%s - BaudRate=%d, wBaudRate=%d, wFlags=0x%04X, bDataBits=%d, bParity=%d, bStopBits=%d, cXon=%d, cXoff=%d, bUartMode=%d",
995 	__FUNCTION__, baud, config->wBaudRate, config->wFlags, config->bDataBits, config->bParity, config->bStopBits, config->cXon, config->cXoff, config->bUartMode);
996 
997 	cpu_to_be16s(&config->wBaudRate);
998 	cpu_to_be16s(&config->wFlags);
999 
1000 	status = ti_command_out_sync(tport->tp_tdev, TI_SET_CONFIG,
1001 		(__u8)(TI_UART1_PORT + port_number), 0, (__u8 *)config,
1002 		sizeof(*config));
1003 	if (status)
1004 		dev_err(&port->dev, "%s - cannot set config on port %d, %d\n", __FUNCTION__, port_number, status);
1005 
1006 	/* SET_CONFIG asserts RTS and DTR, reset them correctly */
1007 	mcr = tport->tp_shadow_mcr;
1008 	/* if baud rate is B0, clear RTS and DTR */
1009 	if ((cflag & CBAUD) == B0)
1010 		mcr &= ~(TI_MCR_DTR | TI_MCR_RTS);
1011 	status = ti_set_mcr(tport, mcr);
1012 	if (status)
1013 		dev_err(&port->dev, "%s - cannot set modem control on port %d, %d\n", __FUNCTION__, port_number, status);
1014 
1015 	kfree(config);
1016 }
1017 
1018 
1019 static int ti_tiocmget(struct usb_serial_port *port, struct file *file)
1020 {
1021 	struct ti_port *tport = usb_get_serial_port_data(port);
1022 	unsigned int result;
1023 	unsigned int msr;
1024 	unsigned int mcr;
1025 
1026 	dbg("%s - port %d", __FUNCTION__, port->number);
1027 
1028 	if (tport == NULL)
1029 		return -ENODEV;
1030 
1031 	msr = tport->tp_msr;
1032 	mcr = tport->tp_shadow_mcr;
1033 
1034 	result = ((mcr & TI_MCR_DTR) ? TIOCM_DTR : 0)
1035 		| ((mcr & TI_MCR_RTS) ? TIOCM_RTS : 0)
1036 		| ((mcr & TI_MCR_LOOP) ? TIOCM_LOOP : 0)
1037 		| ((msr & TI_MSR_CTS) ? TIOCM_CTS : 0)
1038 		| ((msr & TI_MSR_CD) ? TIOCM_CAR : 0)
1039 		| ((msr & TI_MSR_RI) ? TIOCM_RI : 0)
1040 		| ((msr & TI_MSR_DSR) ? TIOCM_DSR : 0);
1041 
1042 	dbg("%s - 0x%04X", __FUNCTION__, result);
1043 
1044 	return result;
1045 }
1046 
1047 
1048 static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
1049 	unsigned int set, unsigned int clear)
1050 {
1051 	struct ti_port *tport = usb_get_serial_port_data(port);
1052 	unsigned int mcr;
1053 
1054 	dbg("%s - port %d", __FUNCTION__, port->number);
1055 
1056 	if (tport == NULL)
1057 		return -ENODEV;
1058 
1059 	mcr = tport->tp_shadow_mcr;
1060 
1061 	if (set & TIOCM_RTS)
1062 		mcr |= TI_MCR_RTS;
1063 	if (set & TIOCM_DTR)
1064 		mcr |= TI_MCR_DTR;
1065 	if (set & TIOCM_LOOP)
1066 		mcr |= TI_MCR_LOOP;
1067 
1068 	if (clear & TIOCM_RTS)
1069 		mcr &= ~TI_MCR_RTS;
1070 	if (clear & TIOCM_DTR)
1071 		mcr &= ~TI_MCR_DTR;
1072 	if (clear & TIOCM_LOOP)
1073 		mcr &= ~TI_MCR_LOOP;
1074 
1075 	return ti_set_mcr(tport, mcr);
1076 }
1077 
1078 
1079 static void ti_break(struct usb_serial_port *port, int break_state)
1080 {
1081 	struct ti_port *tport = usb_get_serial_port_data(port);
1082 	int status;
1083 
1084 	dbg("%s - state = %d", __FUNCTION__, break_state);
1085 
1086 	if (tport == NULL)
1087 		return;
1088 
1089 	ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 0);
1090 
1091 	status = ti_write_byte(tport->tp_tdev,
1092 		tport->tp_uart_base_addr + TI_UART_OFFSET_LCR,
1093 		TI_LCR_BREAK, break_state == -1 ? TI_LCR_BREAK : 0);
1094 
1095 	if (status)
1096 		dbg("%s - error setting break, %d", __FUNCTION__, status);
1097 }
1098 
1099 
1100 static void ti_interrupt_callback(struct urb *urb, struct pt_regs *regs)
1101 {
1102 	struct ti_device *tdev = (struct ti_device *)urb->context;
1103 	struct usb_serial_port *port;
1104 	struct usb_serial *serial = tdev->td_serial;
1105 	struct ti_port *tport;
1106 	struct device *dev = &urb->dev->dev;
1107 	unsigned char *data = urb->transfer_buffer;
1108 	int length = urb->actual_length;
1109 	int port_number;
1110 	int function;
1111 	int status;
1112 	__u8 msr;
1113 
1114 	dbg("%s", __FUNCTION__);
1115 
1116 	switch (urb->status) {
1117 	case 0:
1118 		break;
1119 	case -ECONNRESET:
1120 	case -ENOENT:
1121 	case -ESHUTDOWN:
1122 		dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
1123 		tdev->td_urb_error = 1;
1124 		return;
1125 	default:
1126 		dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status);
1127 		tdev->td_urb_error = 1;
1128 		goto exit;
1129 	}
1130 
1131 	if (length != 2) {
1132 		dbg("%s - bad packet size, %d", __FUNCTION__, length);
1133 		goto exit;
1134 	}
1135 
1136 	if (data[0] == TI_CODE_HARDWARE_ERROR) {
1137 		dev_err(dev, "%s - hardware error, %d\n", __FUNCTION__, data[1]);
1138 		goto exit;
1139 	}
1140 
1141 	port_number = TI_GET_PORT_FROM_CODE(data[0]);
1142 	function = TI_GET_FUNC_FROM_CODE(data[0]);
1143 
1144 	dbg("%s - port_number %d, function %d, data 0x%02X", __FUNCTION__, port_number, function, data[1]);
1145 
1146 	if (port_number >= serial->num_ports) {
1147 		dev_err(dev, "%s - bad port number, %d\n", __FUNCTION__, port_number);
1148 		goto exit;
1149 	}
1150 
1151 	port = serial->port[port_number];
1152 
1153 	tport = usb_get_serial_port_data(port);
1154 	if (!tport)
1155 		goto exit;
1156 
1157 	switch (function) {
1158 	case TI_CODE_DATA_ERROR:
1159 		dev_err(dev, "%s - DATA ERROR, port %d, data 0x%02X\n", __FUNCTION__, port_number, data[1]);
1160 		break;
1161 
1162 	case TI_CODE_MODEM_STATUS:
1163 		msr = data[1];
1164 		dbg("%s - port %d, msr 0x%02X", __FUNCTION__, port_number, msr);
1165 		ti_handle_new_msr(tport, msr);
1166 		break;
1167 
1168 	default:
1169 		dev_err(dev, "%s - unknown interrupt code, 0x%02X\n", __FUNCTION__, data[1]);
1170 		break;
1171 	}
1172 
1173 exit:
1174 	status = usb_submit_urb(urb, GFP_ATOMIC);
1175 	if (status)
1176 		dev_err(dev, "%s - resubmit interrupt urb failed, %d\n", __FUNCTION__, status);
1177 }
1178 
1179 
1180 static void ti_bulk_in_callback(struct urb *urb, struct pt_regs *regs)
1181 {
1182 	struct ti_port *tport = (struct ti_port *)urb->context;
1183 	struct usb_serial_port *port = tport->tp_port;
1184 	struct device *dev = &urb->dev->dev;
1185 	int status = 0;
1186 
1187 	dbg("%s", __FUNCTION__);
1188 
1189 	switch (urb->status) {
1190 	case 0:
1191 		break;
1192 	case -ECONNRESET:
1193 	case -ENOENT:
1194 	case -ESHUTDOWN:
1195 		dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
1196 		tport->tp_tdev->td_urb_error = 1;
1197 		wake_up_interruptible(&tport->tp_write_wait);
1198 		return;
1199 	default:
1200 		dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status );
1201 		tport->tp_tdev->td_urb_error = 1;
1202 		wake_up_interruptible(&tport->tp_write_wait);
1203 	}
1204 
1205 	if (urb->status == -EPIPE)
1206 		goto exit;
1207 
1208 	if (urb->status) {
1209 		dev_err(dev, "%s - stopping read!\n", __FUNCTION__);
1210 		return;
1211 	}
1212 
1213 	if (port->tty && urb->actual_length) {
1214 		usb_serial_debug_data(debug, dev, __FUNCTION__,
1215 			urb->actual_length, urb->transfer_buffer);
1216 
1217 		if (!tport->tp_is_open)
1218 			dbg("%s - port closed, dropping data", __FUNCTION__);
1219 		else
1220 			ti_recv(&urb->dev->dev, port->tty, urb->transfer_buffer,
1221 				urb->actual_length);
1222 
1223 		spin_lock(&tport->tp_lock);
1224 		tport->tp_icount.rx += urb->actual_length;
1225 		spin_unlock(&tport->tp_lock);
1226 	}
1227 
1228 exit:
1229 	/* continue to read unless stopping */
1230 	spin_lock(&tport->tp_lock);
1231 	if (tport->tp_read_urb_state == TI_READ_URB_RUNNING) {
1232 		urb->dev = port->serial->dev;
1233 		status = usb_submit_urb(urb, GFP_ATOMIC);
1234 	} else if (tport->tp_read_urb_state == TI_READ_URB_STOPPING) {
1235 		tport->tp_read_urb_state = TI_READ_URB_STOPPED;
1236 	}
1237 	spin_unlock(&tport->tp_lock);
1238 	if (status)
1239 		dev_err(dev, "%s - resubmit read urb failed, %d\n", __FUNCTION__, status);
1240 }
1241 
1242 
1243 static void ti_bulk_out_callback(struct urb *urb, struct pt_regs *regs)
1244 {
1245 	struct ti_port *tport = (struct ti_port *)urb->context;
1246 	struct usb_serial_port *port = tport->tp_port;
1247 	struct device *dev = &urb->dev->dev;
1248 
1249 	dbg("%s - port %d", __FUNCTION__, port->number);
1250 
1251 	tport->tp_write_urb_in_use = 0;
1252 
1253 	switch (urb->status) {
1254 	case 0:
1255 		break;
1256 	case -ECONNRESET:
1257 	case -ENOENT:
1258 	case -ESHUTDOWN:
1259 		dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
1260 		tport->tp_tdev->td_urb_error = 1;
1261 		wake_up_interruptible(&tport->tp_write_wait);
1262 		return;
1263 	default:
1264 		dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status);
1265 		tport->tp_tdev->td_urb_error = 1;
1266 		wake_up_interruptible(&tport->tp_write_wait);
1267 	}
1268 
1269 	/* send any buffered data */
1270 	ti_send(tport);
1271 }
1272 
1273 
1274 static void ti_recv(struct device *dev, struct tty_struct *tty,
1275 	unsigned char *data, int length)
1276 {
1277 	int cnt;
1278 
1279 	do {
1280 		if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
1281 			tty_flip_buffer_push(tty);
1282 			if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
1283 				dev_err(dev, "%s - dropping data, %d bytes lost\n", __FUNCTION__, length);
1284 				return;
1285 			}
1286 		}
1287 		cnt = min(length, TTY_FLIPBUF_SIZE - tty->flip.count);
1288 		memcpy(tty->flip.char_buf_ptr, data, cnt);
1289 		memset(tty->flip.flag_buf_ptr, 0, cnt);
1290 		tty->flip.char_buf_ptr += cnt;
1291 		tty->flip.flag_buf_ptr += cnt;
1292 		tty->flip.count += cnt;
1293 		data += cnt;
1294 		length -= cnt;
1295 	} while (length > 0);
1296 
1297 	tty_flip_buffer_push(tty);
1298 }
1299 
1300 
1301 static void ti_send(struct ti_port *tport)
1302 {
1303 	int count, result;
1304 	struct usb_serial_port *port = tport->tp_port;
1305 	struct tty_struct *tty = port->tty;
1306 	unsigned long flags;
1307 
1308 
1309 	dbg("%s - port %d", __FUNCTION__, port->number);
1310 
1311 	spin_lock_irqsave(&tport->tp_lock, flags);
1312 
1313 	if (tport->tp_write_urb_in_use) {
1314 		spin_unlock_irqrestore(&tport->tp_lock, flags);
1315 		return;
1316 	}
1317 
1318 	count = ti_buf_get(tport->tp_write_buf,
1319 				port->write_urb->transfer_buffer,
1320 				port->bulk_out_size);
1321 
1322 	if (count == 0) {
1323 		spin_unlock_irqrestore(&tport->tp_lock, flags);
1324 		return;
1325 	}
1326 
1327 	tport->tp_write_urb_in_use = 1;
1328 
1329 	spin_unlock_irqrestore(&tport->tp_lock, flags);
1330 
1331 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);
1332 
1333 	usb_fill_bulk_urb(port->write_urb, port->serial->dev,
1334 			   usb_sndbulkpipe(port->serial->dev,
1335 					    port->bulk_out_endpointAddress),
1336 			   port->write_urb->transfer_buffer, count,
1337 			   ti_bulk_out_callback, tport);
1338 
1339 	result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1340 	if (result) {
1341 		dev_err(&port->dev, "%s - submit write urb failed, %d\n", __FUNCTION__, result);
1342 		tport->tp_write_urb_in_use = 0;
1343 		/* TODO: reschedule ti_send */
1344 	} else {
1345 		spin_lock_irqsave(&tport->tp_lock, flags);
1346 		tport->tp_icount.tx += count;
1347 		spin_unlock_irqrestore(&tport->tp_lock, flags);
1348 	}
1349 
1350 	/* more room in the buffer for new writes, wakeup */
1351 	if (tty)
1352 		tty_wakeup(tty);
1353 	wake_up_interruptible(&tport->tp_write_wait);
1354 }
1355 
1356 
1357 static int ti_set_mcr(struct ti_port *tport, unsigned int mcr)
1358 {
1359 	int status;
1360 
1361 	status = ti_write_byte(tport->tp_tdev,
1362 		tport->tp_uart_base_addr + TI_UART_OFFSET_MCR,
1363 		TI_MCR_RTS | TI_MCR_DTR | TI_MCR_LOOP, mcr);
1364 
1365 	if (!status)
1366 		tport->tp_shadow_mcr = mcr;
1367 
1368 	return status;
1369 }
1370 
1371 
1372 static int ti_get_lsr(struct ti_port *tport)
1373 {
1374 	int size,status;
1375 	struct ti_device *tdev = tport->tp_tdev;
1376 	struct usb_serial_port *port = tport->tp_port;
1377 	int port_number = port->number - port->serial->minor;
1378 	struct ti_port_status *data;
1379 
1380 	dbg("%s - port %d", __FUNCTION__, port->number);
1381 
1382 	size = sizeof(struct ti_port_status);
1383 	data = kmalloc(size, GFP_KERNEL);
1384 	if (!data) {
1385 		dev_err(&port->dev, "%s - out of memory\n", __FUNCTION__);
1386 		return -ENOMEM;
1387 	}
1388 
1389 	status = ti_command_in_sync(tdev, TI_GET_PORT_STATUS,
1390 		(__u8)(TI_UART1_PORT+port_number), 0, (__u8 *)data, size);
1391 	if (status) {
1392 		dev_err(&port->dev, "%s - get port status command failed, %d\n", __FUNCTION__, status);
1393 		goto free_data;
1394 	}
1395 
1396 	dbg("%s - lsr 0x%02X", __FUNCTION__, data->bLSR);
1397 
1398 	tport->tp_lsr = data->bLSR;
1399 
1400 free_data:
1401 	kfree(data);
1402 	return status;
1403 }
1404 
1405 
1406 static int ti_get_serial_info(struct ti_port *tport,
1407 	struct serial_struct __user *ret_arg)
1408 {
1409 	struct usb_serial_port *port = tport->tp_port;
1410 	struct serial_struct ret_serial;
1411 
1412 	if (!ret_arg)
1413 		return -EFAULT;
1414 
1415 	memset(&ret_serial, 0, sizeof(ret_serial));
1416 
1417 	ret_serial.type = PORT_16550A;
1418 	ret_serial.line = port->serial->minor;
1419 	ret_serial.port = port->number - port->serial->minor;
1420 	ret_serial.flags = tport->tp_flags;
1421 	ret_serial.xmit_fifo_size = TI_WRITE_BUF_SIZE;
1422 	ret_serial.baud_base = tport->tp_tdev->td_is_3410 ? 921600 : 460800;
1423 	ret_serial.closing_wait = tport->tp_closing_wait;
1424 
1425 	if (copy_to_user(ret_arg, &ret_serial, sizeof(*ret_arg)))
1426 		return -EFAULT;
1427 
1428 	return 0;
1429 }
1430 
1431 
1432 static int ti_set_serial_info(struct ti_port *tport,
1433 	struct serial_struct __user *new_arg)
1434 {
1435 	struct usb_serial_port *port = tport->tp_port;
1436 	struct serial_struct new_serial;
1437 
1438 	if (copy_from_user(&new_serial, new_arg, sizeof(new_serial)))
1439 		return -EFAULT;
1440 
1441 	tport->tp_flags = new_serial.flags & TI_SET_SERIAL_FLAGS;
1442 	if (port->tty)
1443 		port->tty->low_latency =
1444 			(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1445 	tport->tp_closing_wait = new_serial.closing_wait;
1446 
1447 	return 0;
1448 }
1449 
1450 
1451 static void ti_handle_new_msr(struct ti_port *tport, __u8 msr)
1452 {
1453 	struct async_icount *icount;
1454 	struct tty_struct *tty;
1455 	unsigned long flags;
1456 
1457 	dbg("%s - msr 0x%02X", __FUNCTION__, msr);
1458 
1459 	if (msr & TI_MSR_DELTA_MASK) {
1460 		spin_lock_irqsave(&tport->tp_lock, flags);
1461 		icount = &tport->tp_icount;
1462 		if (msr & TI_MSR_DELTA_CTS)
1463 			icount->cts++;
1464 		if (msr & TI_MSR_DELTA_DSR)
1465 			icount->dsr++;
1466 		if (msr & TI_MSR_DELTA_CD)
1467 			icount->dcd++;
1468 		if (msr & TI_MSR_DELTA_RI)
1469 			icount->rng++;
1470 		wake_up_interruptible(&tport->tp_msr_wait);
1471 		spin_unlock_irqrestore(&tport->tp_lock, flags);
1472 	}
1473 
1474 	tport->tp_msr = msr & TI_MSR_MASK;
1475 
1476 	/* handle CTS flow control */
1477 	tty = tport->tp_port->tty;
1478 	if (tty && C_CRTSCTS(tty)) {
1479 		if (msr & TI_MSR_CTS) {
1480 			tty->hw_stopped = 0;
1481 			tty_wakeup(tty);
1482 		} else {
1483 			tty->hw_stopped = 1;
1484 		}
1485 	}
1486 }
1487 
1488 
1489 static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush)
1490 {
1491 	struct ti_device *tdev = tport->tp_tdev;
1492 	struct usb_serial_port *port = tport->tp_port;
1493 	wait_queue_t wait;
1494 	unsigned long flags;
1495 
1496 	dbg("%s - port %d", __FUNCTION__, port->number);
1497 
1498 	spin_lock_irqsave(&tport->tp_lock, flags);
1499 
1500 	/* wait for data to drain from the buffer */
1501 	tdev->td_urb_error = 0;
1502 	init_waitqueue_entry(&wait, current);
1503 	add_wait_queue(&tport->tp_write_wait, &wait);
1504 	for (;;) {
1505 		set_current_state(TASK_INTERRUPTIBLE);
1506 		if (ti_buf_data_avail(tport->tp_write_buf) == 0
1507 		|| timeout == 0 || signal_pending(current)
1508 		|| tdev->td_urb_error
1509 		|| !usb_get_intfdata(port->serial->interface))  /* disconnect */
1510 			break;
1511 		spin_unlock_irqrestore(&tport->tp_lock, flags);
1512 		timeout = schedule_timeout(timeout);
1513 		spin_lock_irqsave(&tport->tp_lock, flags);
1514 	}
1515 	set_current_state(TASK_RUNNING);
1516 	remove_wait_queue(&tport->tp_write_wait, &wait);
1517 
1518 	/* flush any remaining data in the buffer */
1519 	if (flush)
1520 		ti_buf_clear(tport->tp_write_buf);
1521 
1522 	spin_unlock_irqrestore(&tport->tp_lock, flags);
1523 
1524 	/* wait for data to drain from the device */
1525 	/* wait for empty tx register, plus 20 ms */
1526 	timeout += jiffies;
1527 	tport->tp_lsr &= ~TI_LSR_TX_EMPTY;
1528 	while ((long)(jiffies - timeout) < 0 && !signal_pending(current)
1529 	&& !(tport->tp_lsr&TI_LSR_TX_EMPTY) && !tdev->td_urb_error
1530 	&& usb_get_intfdata(port->serial->interface)) {  /* not disconnected */
1531 		if (ti_get_lsr(tport))
1532 			break;
1533 		msleep_interruptible(20);
1534 	}
1535 }
1536 
1537 
1538 static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty)
1539 {
1540 	unsigned long flags;
1541 
1542 	spin_lock_irqsave(&tport->tp_lock, flags);
1543 
1544 	if (tport->tp_read_urb_state == TI_READ_URB_RUNNING)
1545 		tport->tp_read_urb_state = TI_READ_URB_STOPPING;
1546 
1547 	spin_unlock_irqrestore(&tport->tp_lock, flags);
1548 }
1549 
1550 
1551 static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty)
1552 {
1553 	struct urb *urb;
1554 	int status = 0;
1555 	unsigned long flags;
1556 
1557 	spin_lock_irqsave(&tport->tp_lock, flags);
1558 
1559 	if (tport->tp_read_urb_state == TI_READ_URB_STOPPED) {
1560 		urb = tport->tp_port->read_urb;
1561 		urb->complete = ti_bulk_in_callback;
1562 		urb->context = tport;
1563 		urb->dev = tport->tp_port->serial->dev;
1564 		status = usb_submit_urb(urb, GFP_KERNEL);
1565 	}
1566 	tport->tp_read_urb_state = TI_READ_URB_RUNNING;
1567 
1568 	spin_unlock_irqrestore(&tport->tp_lock, flags);
1569 
1570 	return status;
1571 }
1572 
1573 
1574 static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
1575 	__u16 moduleid, __u16 value, __u8 *data, int size)
1576 {
1577 	int status;
1578 
1579 	status = usb_control_msg(tdev->td_serial->dev,
1580 		usb_sndctrlpipe(tdev->td_serial->dev, 0), command,
1581 		(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT),
1582 		value, moduleid, data, size, 1000);
1583 
1584 	if (status == size)
1585 		status = 0;
1586 
1587 	if (status > 0)
1588 		status = -ECOMM;
1589 
1590 	return status;
1591 }
1592 
1593 
1594 static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
1595 	__u16 moduleid, __u16 value, __u8 *data, int size)
1596 {
1597 	int status;
1598 
1599 	status = usb_control_msg(tdev->td_serial->dev,
1600 		usb_rcvctrlpipe(tdev->td_serial->dev, 0), command,
1601 		(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN),
1602 		value, moduleid, data, size, 1000);
1603 
1604 	if (status == size)
1605 		status = 0;
1606 
1607 	if (status > 0)
1608 		status = -ECOMM;
1609 
1610 	return status;
1611 }
1612 
1613 
1614 static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
1615 	__u8 mask, __u8 byte)
1616 {
1617 	int status;
1618 	unsigned int size;
1619 	struct ti_write_data_bytes *data;
1620 	struct device *dev = &tdev->td_serial->dev->dev;
1621 
1622 	dbg("%s - addr 0x%08lX, mask 0x%02X, byte 0x%02X", __FUNCTION__, addr, mask, byte);
1623 
1624 	size = sizeof(struct ti_write_data_bytes) + 2;
1625 	data = kmalloc(size, GFP_KERNEL);
1626 	if (!data) {
1627 		dev_err(dev, "%s - out of memory\n", __FUNCTION__);
1628 		return -ENOMEM;
1629 	}
1630 
1631 	data->bAddrType = TI_RW_DATA_ADDR_XDATA;
1632 	data->bDataType = TI_RW_DATA_BYTE;
1633 	data->bDataCounter = 1;
1634 	data->wBaseAddrHi = cpu_to_be16(addr>>16);
1635 	data->wBaseAddrLo = cpu_to_be16(addr);
1636 	data->bData[0] = mask;
1637 	data->bData[1] = byte;
1638 
1639 	status = ti_command_out_sync(tdev, TI_WRITE_DATA, TI_RAM_PORT, 0,
1640 		(__u8 *)data, size);
1641 
1642 	if (status < 0)
1643 		dev_err(dev, "%s - failed, %d\n", __FUNCTION__, status);
1644 
1645 	kfree(data);
1646 
1647 	return status;
1648 }
1649 
1650 
1651 static int ti_download_firmware(struct ti_device *tdev,
1652 	unsigned char *firmware, unsigned int firmware_size)
1653 {
1654 	int status = 0;
1655 	int buffer_size;
1656 	int pos;
1657 	int len;
1658 	int done;
1659 	__u8 cs = 0;
1660 	__u8 *buffer;
1661 	struct usb_device *dev = tdev->td_serial->dev;
1662 	struct ti_firmware_header *header;
1663 	unsigned int pipe = usb_sndbulkpipe(dev,
1664 		tdev->td_serial->port[0]->bulk_out_endpointAddress);
1665 
1666 
1667 	buffer_size = TI_FIRMWARE_BUF_SIZE + sizeof(struct ti_firmware_header);
1668 	buffer = kmalloc(buffer_size, GFP_KERNEL);
1669 	if (!buffer) {
1670 		dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
1671 		return -ENOMEM;
1672 	}
1673 
1674 	memcpy(buffer, firmware, firmware_size);
1675 	memset(buffer+firmware_size, 0xff, buffer_size-firmware_size);
1676 
1677 	for(pos = sizeof(struct ti_firmware_header); pos < buffer_size; pos++)
1678 		cs = (__u8)(cs + buffer[pos]);
1679 
1680 	header = (struct ti_firmware_header *)buffer;
1681 	header->wLength = cpu_to_le16((__u16)(buffer_size - sizeof(struct ti_firmware_header)));
1682 	header->bCheckSum = cs;
1683 
1684 	dbg("%s - downloading firmware", __FUNCTION__);
1685 	for (pos = 0; pos < buffer_size; pos += done) {
1686 		len = min(buffer_size - pos, TI_DOWNLOAD_MAX_PACKET_SIZE);
1687 		status = usb_bulk_msg(dev, pipe, buffer+pos, len, &done, 1000);
1688 		if (status)
1689 			break;
1690 	}
1691 
1692 	kfree(buffer);
1693 
1694 	if (status) {
1695 		dev_err(&dev->dev, "%s - error downloading firmware, %d\n", __FUNCTION__, status);
1696 		return status;
1697 	}
1698 
1699 	dbg("%s - download successful", __FUNCTION__);
1700 
1701 	return 0;
1702 }
1703 
1704 
1705 /* Circular Buffer Functions */
1706 
1707 /*
1708  * ti_buf_alloc
1709  *
1710  * Allocate a circular buffer and all associated memory.
1711  */
1712 
1713 static struct circ_buf *ti_buf_alloc(void)
1714 {
1715 	struct circ_buf *cb;
1716 
1717 	cb = (struct circ_buf *)kmalloc(sizeof(struct circ_buf), GFP_KERNEL);
1718 	if (cb == NULL)
1719 		return NULL;
1720 
1721 	cb->buf = kmalloc(TI_WRITE_BUF_SIZE, GFP_KERNEL);
1722 	if (cb->buf == NULL) {
1723 		kfree(cb);
1724 		return NULL;
1725 	}
1726 
1727 	ti_buf_clear(cb);
1728 
1729 	return cb;
1730 }
1731 
1732 
1733 /*
1734  * ti_buf_free
1735  *
1736  * Free the buffer and all associated memory.
1737  */
1738 
1739 static void ti_buf_free(struct circ_buf *cb)
1740 {
1741 	kfree(cb->buf);
1742 	kfree(cb);
1743 }
1744 
1745 
1746 /*
1747  * ti_buf_clear
1748  *
1749  * Clear out all data in the circular buffer.
1750  */
1751 
1752 static void ti_buf_clear(struct circ_buf *cb)
1753 {
1754 	cb->head = cb->tail = 0;
1755 }
1756 
1757 
1758 /*
1759  * ti_buf_data_avail
1760  *
1761  * Return the number of bytes of data available in the circular
1762  * buffer.
1763  */
1764 
1765 static int ti_buf_data_avail(struct circ_buf *cb)
1766 {
1767 	return CIRC_CNT(cb->head,cb->tail,TI_WRITE_BUF_SIZE);
1768 }
1769 
1770 
1771 /*
1772  * ti_buf_space_avail
1773  *
1774  * Return the number of bytes of space available in the circular
1775  * buffer.
1776  */
1777 
1778 static int ti_buf_space_avail(struct circ_buf *cb)
1779 {
1780 	return CIRC_SPACE(cb->head,cb->tail,TI_WRITE_BUF_SIZE);
1781 }
1782 
1783 
1784 /*
1785  * ti_buf_put
1786  *
1787  * Copy data data from a user buffer and put it into the circular buffer.
1788  * Restrict to the amount of space available.
1789  *
1790  * Return the number of bytes copied.
1791  */
1792 
1793 static int ti_buf_put(struct circ_buf *cb, const char *buf, int count)
1794 {
1795 	int c, ret = 0;
1796 
1797 	while (1) {
1798 		c = CIRC_SPACE_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1799 		if (count < c)
1800 			c = count;
1801 		if (c <= 0)
1802 			break;
1803 		memcpy(cb->buf + cb->head, buf, c);
1804 		cb->head = (cb->head + c) & (TI_WRITE_BUF_SIZE-1);
1805 		buf += c;
1806 		count -= c;
1807 		ret += c;
1808 	}
1809 
1810 	return ret;
1811 }
1812 
1813 
1814 /*
1815  * ti_buf_get
1816  *
1817  * Get data from the circular buffer and copy to the given buffer.
1818  * Restrict to the amount of data available.
1819  *
1820  * Return the number of bytes copied.
1821  */
1822 
1823 static int ti_buf_get(struct circ_buf *cb, char *buf, int count)
1824 {
1825 	int c, ret = 0;
1826 
1827 	while (1) {
1828 		c = CIRC_CNT_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1829 		if (count < c)
1830 			c = count;
1831 		if (c <= 0)
1832 			break;
1833 		memcpy(buf, cb->buf + cb->tail, c);
1834 		cb->tail = (cb->tail + c) & (TI_WRITE_BUF_SIZE-1);
1835 		buf += c;
1836 		count -= c;
1837 		ret += c;
1838 	}
1839 
1840 	return ret;
1841 }
1842