tty: Fix leak in ti-usb
[linux-2.6.git] / drivers / usb / serial / ti_usb_3410_5052.c
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
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
23 #include <linux/firmware.h>
24 #include <linux/init.h>
25 #include <linux/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_driver.h>
28 #include <linux/tty_flip.h>
29 #include <linux/module.h>
30 #include <linux/spinlock.h>
31 #include <linux/ioctl.h>
32 #include <linux/serial.h>
33 #include <linux/circ_buf.h>
34 #include <linux/mutex.h>
35 #include <linux/uaccess.h>
36 #include <linux/usb.h>
37 #include <linux/usb/serial.h>
38
39 #include "ti_usb_3410_5052.h"
40
41 /* Defines */
42
43 #define TI_DRIVER_VERSION       "v0.9"
44 #define TI_DRIVER_AUTHOR        "Al Borchers <alborchers@steinerpoint.com>"
45 #define TI_DRIVER_DESC          "TI USB 3410/5052 Serial Driver"
46
47 #define TI_FIRMWARE_BUF_SIZE    16284
48
49 #define TI_WRITE_BUF_SIZE       1024
50
51 #define TI_TRANSFER_TIMEOUT     2
52
53 #define TI_DEFAULT_LOW_LATENCY  0
54 #define TI_DEFAULT_CLOSING_WAIT 4000            /* in .01 secs */
55
56 /* supported setserial flags */
57 #define TI_SET_SERIAL_FLAGS     (ASYNC_LOW_LATENCY)
58
59 /* read urb states */
60 #define TI_READ_URB_RUNNING     0
61 #define TI_READ_URB_STOPPING    1
62 #define TI_READ_URB_STOPPED     2
63
64 #define TI_EXTRA_VID_PID_COUNT  5
65
66
67 /* Structures */
68
69 struct ti_port {
70         int                     tp_is_open;
71         __u8                    tp_msr;
72         __u8                    tp_lsr;
73         __u8                    tp_shadow_mcr;
74         __u8                    tp_uart_mode;   /* 232 or 485 modes */
75         unsigned int            tp_uart_base_addr;
76         int                     tp_flags;
77         int                     tp_closing_wait;/* in .01 secs */
78         struct async_icount     tp_icount;
79         wait_queue_head_t       tp_msr_wait;    /* wait for msr change */
80         wait_queue_head_t       tp_write_wait;
81         struct ti_device        *tp_tdev;
82         struct usb_serial_port  *tp_port;
83         spinlock_t              tp_lock;
84         int                     tp_read_urb_state;
85         int                     tp_write_urb_in_use;
86         struct circ_buf         *tp_write_buf;
87 };
88
89 struct ti_device {
90         struct mutex            td_open_close_lock;
91         int                     td_open_port_count;
92         struct usb_serial       *td_serial;
93         int                     td_is_3410;
94         int                     td_urb_error;
95 };
96
97
98 /* Function Declarations */
99
100 static int ti_startup(struct usb_serial *serial);
101 static void ti_shutdown(struct usb_serial *serial);
102 static int ti_open(struct tty_struct *tty, struct usb_serial_port *port,
103                 struct file *file);
104 static void ti_close(struct tty_struct *tty, struct usb_serial_port *port,
105                 struct file *file);
106 static int ti_write(struct tty_struct *tty, struct usb_serial_port *port,
107                 const unsigned char *data, int count);
108 static int ti_write_room(struct tty_struct *tty);
109 static int ti_chars_in_buffer(struct tty_struct *tty);
110 static void ti_throttle(struct tty_struct *tty);
111 static void ti_unthrottle(struct tty_struct *tty);
112 static int ti_ioctl(struct tty_struct *tty, struct file *file,
113                 unsigned int cmd, unsigned long arg);
114 static void ti_set_termios(struct tty_struct *tty,
115                 struct usb_serial_port *port, struct ktermios *old_termios);
116 static int ti_tiocmget(struct tty_struct *tty, struct file *file);
117 static int ti_tiocmset(struct tty_struct *tty, struct file *file,
118                 unsigned int set, unsigned int clear);
119 static void ti_break(struct tty_struct *tty, int break_state);
120 static void ti_interrupt_callback(struct urb *urb);
121 static void ti_bulk_in_callback(struct urb *urb);
122 static void ti_bulk_out_callback(struct urb *urb);
123
124 static void ti_recv(struct device *dev, struct tty_struct *tty,
125         unsigned char *data, int length);
126 static void ti_send(struct ti_port *tport);
127 static int ti_set_mcr(struct ti_port *tport, unsigned int mcr);
128 static int ti_get_lsr(struct ti_port *tport);
129 static int ti_get_serial_info(struct ti_port *tport,
130         struct serial_struct __user *ret_arg);
131 static int ti_set_serial_info(struct tty_struct *tty, struct ti_port *tport,
132         struct serial_struct __user *new_arg);
133 static void ti_handle_new_msr(struct ti_port *tport, __u8 msr);
134
135 static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush);
136
137 static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty);
138 static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty);
139
140 static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
141         __u16 moduleid, __u16 value, __u8 *data, int size);
142 static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
143         __u16 moduleid, __u16 value, __u8 *data, int size);
144
145 static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
146         __u8 mask, __u8 byte);
147
148 static int ti_download_firmware(struct ti_device *tdev);
149
150 /* circular buffer */
151 static struct circ_buf *ti_buf_alloc(void);
152 static void ti_buf_free(struct circ_buf *cb);
153 static void ti_buf_clear(struct circ_buf *cb);
154 static int ti_buf_data_avail(struct circ_buf *cb);
155 static int ti_buf_space_avail(struct circ_buf *cb);
156 static int ti_buf_put(struct circ_buf *cb, const char *buf, int count);
157 static int ti_buf_get(struct circ_buf *cb, char *buf, int count);
158
159
160 /* Data */
161
162 /* module parameters */
163 static int debug;
164 static int low_latency = TI_DEFAULT_LOW_LATENCY;
165 static int closing_wait = TI_DEFAULT_CLOSING_WAIT;
166 static ushort vendor_3410[TI_EXTRA_VID_PID_COUNT];
167 static unsigned int vendor_3410_count;
168 static ushort product_3410[TI_EXTRA_VID_PID_COUNT];
169 static unsigned int product_3410_count;
170 static ushort vendor_5052[TI_EXTRA_VID_PID_COUNT];
171 static unsigned int vendor_5052_count;
172 static ushort product_5052[TI_EXTRA_VID_PID_COUNT];
173 static unsigned int product_5052_count;
174
175 /* supported devices */
176 /* the array dimension is the number of default entries plus */
177 /* TI_EXTRA_VID_PID_COUNT user defined entries plus 1 terminating */
178 /* null entry */
179 static struct usb_device_id ti_id_table_3410[10+TI_EXTRA_VID_PID_COUNT+1] = {
180         { USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
181         { USB_DEVICE(TI_VENDOR_ID, TI_3410_EZ430_ID) },
182         { USB_DEVICE(MTS_VENDOR_ID, MTS_GSM_NO_FW_PRODUCT_ID) },
183         { USB_DEVICE(MTS_VENDOR_ID, MTS_CDMA_NO_FW_PRODUCT_ID) },
184         { USB_DEVICE(MTS_VENDOR_ID, MTS_CDMA_PRODUCT_ID) },
185         { USB_DEVICE(MTS_VENDOR_ID, MTS_GSM_PRODUCT_ID) },
186         { USB_DEVICE(MTS_VENDOR_ID, MTS_EDGE_PRODUCT_ID) },
187         { USB_DEVICE(IBM_VENDOR_ID, IBM_4543_PRODUCT_ID) },
188         { USB_DEVICE(IBM_VENDOR_ID, IBM_454B_PRODUCT_ID) },
189         { USB_DEVICE(IBM_VENDOR_ID, IBM_454C_PRODUCT_ID) },
190 };
191
192 static struct usb_device_id ti_id_table_5052[5+TI_EXTRA_VID_PID_COUNT+1] = {
193         { USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
194         { USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
195         { USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
196         { USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
197         { USB_DEVICE(IBM_VENDOR_ID, IBM_4543_PRODUCT_ID) },
198 };
199
200 static struct usb_device_id ti_id_table_combined[14+2*TI_EXTRA_VID_PID_COUNT+1] = {
201         { USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
202         { USB_DEVICE(TI_VENDOR_ID, TI_3410_EZ430_ID) },
203         { USB_DEVICE(MTS_VENDOR_ID, MTS_GSM_NO_FW_PRODUCT_ID) },
204         { USB_DEVICE(MTS_VENDOR_ID, MTS_CDMA_NO_FW_PRODUCT_ID) },
205         { USB_DEVICE(MTS_VENDOR_ID, MTS_CDMA_PRODUCT_ID) },
206         { USB_DEVICE(MTS_VENDOR_ID, MTS_GSM_PRODUCT_ID) },
207         { USB_DEVICE(MTS_VENDOR_ID, MTS_EDGE_PRODUCT_ID) },
208         { USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
209         { USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
210         { USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
211         { USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
212         { USB_DEVICE(IBM_VENDOR_ID, IBM_4543_PRODUCT_ID) },
213         { USB_DEVICE(IBM_VENDOR_ID, IBM_454B_PRODUCT_ID) },
214         { USB_DEVICE(IBM_VENDOR_ID, IBM_454C_PRODUCT_ID) },
215         { }
216 };
217
218 static struct usb_driver ti_usb_driver = {
219         .name                   = "ti_usb_3410_5052",
220         .probe                  = usb_serial_probe,
221         .disconnect             = usb_serial_disconnect,
222         .id_table               = ti_id_table_combined,
223         .no_dynamic_id =        1,
224 };
225
226 static struct usb_serial_driver ti_1port_device = {
227         .driver = {
228                 .owner          = THIS_MODULE,
229                 .name           = "ti_usb_3410_5052_1",
230         },
231         .description            = "TI USB 3410 1 port adapter",
232         .usb_driver             = &ti_usb_driver,
233         .id_table               = ti_id_table_3410,
234         .num_ports              = 1,
235         .attach                 = ti_startup,
236         .shutdown               = ti_shutdown,
237         .open                   = ti_open,
238         .close                  = ti_close,
239         .write                  = ti_write,
240         .write_room             = ti_write_room,
241         .chars_in_buffer        = ti_chars_in_buffer,
242         .throttle               = ti_throttle,
243         .unthrottle             = ti_unthrottle,
244         .ioctl                  = ti_ioctl,
245         .set_termios            = ti_set_termios,
246         .tiocmget               = ti_tiocmget,
247         .tiocmset               = ti_tiocmset,
248         .break_ctl              = ti_break,
249         .read_int_callback      = ti_interrupt_callback,
250         .read_bulk_callback     = ti_bulk_in_callback,
251         .write_bulk_callback    = ti_bulk_out_callback,
252 };
253
254 static struct usb_serial_driver ti_2port_device = {
255         .driver = {
256                 .owner          = THIS_MODULE,
257                 .name           = "ti_usb_3410_5052_2",
258         },
259         .description            = "TI USB 5052 2 port adapter",
260         .usb_driver             = &ti_usb_driver,
261         .id_table               = ti_id_table_5052,
262         .num_ports              = 2,
263         .attach                 = ti_startup,
264         .shutdown               = ti_shutdown,
265         .open                   = ti_open,
266         .close                  = ti_close,
267         .write                  = ti_write,
268         .write_room             = ti_write_room,
269         .chars_in_buffer        = ti_chars_in_buffer,
270         .throttle               = ti_throttle,
271         .unthrottle             = ti_unthrottle,
272         .ioctl                  = ti_ioctl,
273         .set_termios            = ti_set_termios,
274         .tiocmget               = ti_tiocmget,
275         .tiocmset               = ti_tiocmset,
276         .break_ctl              = ti_break,
277         .read_int_callback      = ti_interrupt_callback,
278         .read_bulk_callback     = ti_bulk_in_callback,
279         .write_bulk_callback    = ti_bulk_out_callback,
280 };
281
282
283 /* Module */
284
285 MODULE_AUTHOR(TI_DRIVER_AUTHOR);
286 MODULE_DESCRIPTION(TI_DRIVER_DESC);
287 MODULE_VERSION(TI_DRIVER_VERSION);
288 MODULE_LICENSE("GPL");
289
290 MODULE_FIRMWARE("ti_3410.fw");
291 MODULE_FIRMWARE("ti_5052.fw");
292 MODULE_FIRMWARE("mts_cdma.fw");
293 MODULE_FIRMWARE("mts_gsm.fw");
294 MODULE_FIRMWARE("mts_edge.fw");
295
296 module_param(debug, bool, S_IRUGO | S_IWUSR);
297 MODULE_PARM_DESC(debug, "Enable debugging, 0=no, 1=yes");
298
299 module_param(low_latency, bool, S_IRUGO | S_IWUSR);
300 MODULE_PARM_DESC(low_latency,
301                 "TTY low_latency flag, 0=off, 1=on, default is off");
302
303 module_param(closing_wait, int, S_IRUGO | S_IWUSR);
304 MODULE_PARM_DESC(closing_wait,
305     "Maximum wait for data to drain in close, in .01 secs, default is 4000");
306
307 module_param_array(vendor_3410, ushort, &vendor_3410_count, S_IRUGO);
308 MODULE_PARM_DESC(vendor_3410,
309                 "Vendor ids for 3410 based devices, 1-5 short integers");
310 module_param_array(product_3410, ushort, &product_3410_count, S_IRUGO);
311 MODULE_PARM_DESC(product_3410,
312                 "Product ids for 3410 based devices, 1-5 short integers");
313 module_param_array(vendor_5052, ushort, &vendor_5052_count, S_IRUGO);
314 MODULE_PARM_DESC(vendor_5052,
315                 "Vendor ids for 5052 based devices, 1-5 short integers");
316 module_param_array(product_5052, ushort, &product_5052_count, S_IRUGO);
317 MODULE_PARM_DESC(product_5052,
318                 "Product ids for 5052 based devices, 1-5 short integers");
319
320 MODULE_DEVICE_TABLE(usb, ti_id_table_combined);
321
322
323 /* Functions */
324
325 static int __init ti_init(void)
326 {
327         int i, j, c;
328         int ret;
329
330         /* insert extra vendor and product ids */
331         c = ARRAY_SIZE(ti_id_table_combined) - 2 * TI_EXTRA_VID_PID_COUNT - 1;
332         j = ARRAY_SIZE(ti_id_table_3410) - TI_EXTRA_VID_PID_COUNT - 1;
333         for (i = 0; i < min(vendor_3410_count, product_3410_count); i++, j++, c++) {
334                 ti_id_table_3410[j].idVendor = vendor_3410[i];
335                 ti_id_table_3410[j].idProduct = product_3410[i];
336                 ti_id_table_3410[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
337                 ti_id_table_combined[c].idVendor = vendor_3410[i];
338                 ti_id_table_combined[c].idProduct = product_3410[i];
339                 ti_id_table_combined[c].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
340         }
341         j = ARRAY_SIZE(ti_id_table_5052) - TI_EXTRA_VID_PID_COUNT - 1;
342         for (i = 0; i < min(vendor_5052_count, product_5052_count); i++, j++, c++) {
343                 ti_id_table_5052[j].idVendor = vendor_5052[i];
344                 ti_id_table_5052[j].idProduct = product_5052[i];
345                 ti_id_table_5052[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
346                 ti_id_table_combined[c].idVendor = vendor_5052[i];
347                 ti_id_table_combined[c].idProduct = product_5052[i];
348                 ti_id_table_combined[c].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
349         }
350
351         ret = usb_serial_register(&ti_1port_device);
352         if (ret)
353                 goto failed_1port;
354         ret = usb_serial_register(&ti_2port_device);
355         if (ret)
356                 goto failed_2port;
357
358         ret = usb_register(&ti_usb_driver);
359         if (ret)
360                 goto failed_usb;
361
362         printk(KERN_INFO KBUILD_MODNAME ": " TI_DRIVER_VERSION ":"
363                TI_DRIVER_DESC "\n");
364
365         return 0;
366
367 failed_usb:
368         usb_serial_deregister(&ti_2port_device);
369 failed_2port:
370         usb_serial_deregister(&ti_1port_device);
371 failed_1port:
372         return ret;
373 }
374
375
376 static void __exit ti_exit(void)
377 {
378         usb_serial_deregister(&ti_1port_device);
379         usb_serial_deregister(&ti_2port_device);
380         usb_deregister(&ti_usb_driver);
381 }
382
383
384 module_init(ti_init);
385 module_exit(ti_exit);
386
387
388 static int ti_startup(struct usb_serial *serial)
389 {
390         struct ti_device *tdev;
391         struct ti_port *tport;
392         struct usb_device *dev = serial->dev;
393         int status;
394         int i;
395
396
397         dbg("%s - product 0x%4X, num configurations %d, configuration value %d",
398             __func__, le16_to_cpu(dev->descriptor.idProduct),
399             dev->descriptor.bNumConfigurations,
400             dev->actconfig->desc.bConfigurationValue);
401
402         /* create device structure */
403         tdev = kzalloc(sizeof(struct ti_device), GFP_KERNEL);
404         if (tdev == NULL) {
405                 dev_err(&dev->dev, "%s - out of memory\n", __func__);
406                 return -ENOMEM;
407         }
408         mutex_init(&tdev->td_open_close_lock);
409         tdev->td_serial = serial;
410         usb_set_serial_data(serial, tdev);
411
412         /* determine device type */
413         if (usb_match_id(serial->interface, ti_id_table_3410))
414                 tdev->td_is_3410 = 1;
415         dbg("%s - device type is %s", __func__,
416                                 tdev->td_is_3410 ? "3410" : "5052");
417
418         /* if we have only 1 configuration, download firmware */
419         if (dev->descriptor.bNumConfigurations == 1) {
420                 if ((status = ti_download_firmware(tdev)) != 0)
421                         goto free_tdev;
422
423                 /* 3410 must be reset, 5052 resets itself */
424                 if (tdev->td_is_3410) {
425                         msleep_interruptible(100);
426                         usb_reset_device(dev);
427                 }
428
429                 status = -ENODEV;
430                 goto free_tdev;
431         }
432
433         /* the second configuration must be set */
434         if (dev->actconfig->desc.bConfigurationValue == TI_BOOT_CONFIG) {
435                 status = usb_driver_set_configuration(dev, TI_ACTIVE_CONFIG);
436                 status = status ? status : -ENODEV;
437                 goto free_tdev;
438         }
439
440         /* set up port structures */
441         for (i = 0; i < serial->num_ports; ++i) {
442                 tport = kzalloc(sizeof(struct ti_port), GFP_KERNEL);
443                 if (tport == NULL) {
444                         dev_err(&dev->dev, "%s - out of memory\n", __func__);
445                         status = -ENOMEM;
446                         goto free_tports;
447                 }
448                 spin_lock_init(&tport->tp_lock);
449                 tport->tp_uart_base_addr = (i == 0 ?
450                                 TI_UART1_BASE_ADDR : TI_UART2_BASE_ADDR);
451                 tport->tp_flags = low_latency ? ASYNC_LOW_LATENCY : 0;
452                 tport->tp_closing_wait = closing_wait;
453                 init_waitqueue_head(&tport->tp_msr_wait);
454                 init_waitqueue_head(&tport->tp_write_wait);
455                 tport->tp_write_buf = ti_buf_alloc();
456                 if (tport->tp_write_buf == NULL) {
457                         dev_err(&dev->dev, "%s - out of memory\n", __func__);
458                         kfree(tport);
459                         status = -ENOMEM;
460                         goto free_tports;
461                 }
462                 tport->tp_port = serial->port[i];
463                 tport->tp_tdev = tdev;
464                 usb_set_serial_port_data(serial->port[i], tport);
465                 tport->tp_uart_mode = 0;        /* default is RS232 */
466         }
467
468         return 0;
469
470 free_tports:
471         for (--i; i >= 0; --i) {
472                 tport = usb_get_serial_port_data(serial->port[i]);
473                 ti_buf_free(tport->tp_write_buf);
474                 kfree(tport);
475                 usb_set_serial_port_data(serial->port[i], NULL);
476         }
477 free_tdev:
478         kfree(tdev);
479         usb_set_serial_data(serial, NULL);
480         return status;
481 }
482
483
484 static void ti_shutdown(struct usb_serial *serial)
485 {
486         int i;
487         struct ti_device *tdev = usb_get_serial_data(serial);
488         struct ti_port *tport;
489
490         dbg("%s", __func__);
491
492         for (i = 0; i < serial->num_ports; ++i) {
493                 tport = usb_get_serial_port_data(serial->port[i]);
494                 if (tport) {
495                         ti_buf_free(tport->tp_write_buf);
496                         kfree(tport);
497                         usb_set_serial_port_data(serial->port[i], NULL);
498                 }
499         }
500
501         kfree(tdev);
502         usb_set_serial_data(serial, NULL);
503 }
504
505
506 static int ti_open(struct tty_struct *tty,
507                         struct usb_serial_port *port, struct file *file)
508 {
509         struct ti_port *tport = usb_get_serial_port_data(port);
510         struct ti_device *tdev;
511         struct usb_device *dev;
512         struct urb *urb;
513         int port_number;
514         int status;
515         __u16 open_settings = (__u8)(TI_PIPE_MODE_CONTINOUS |
516                              TI_PIPE_TIMEOUT_ENABLE |
517                              (TI_TRANSFER_TIMEOUT << 2));
518
519         dbg("%s - port %d", __func__, port->number);
520
521         if (tport == NULL)
522                 return -ENODEV;
523
524         dev = port->serial->dev;
525         tdev = tport->tp_tdev;
526
527         /* only one open on any port on a device at a time */
528         if (mutex_lock_interruptible(&tdev->td_open_close_lock))
529                 return -ERESTARTSYS;
530
531         if (tty)
532                 tty->low_latency =
533                                 (tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
534
535         port_number = port->number - port->serial->minor;
536
537         memset(&(tport->tp_icount), 0x00, sizeof(tport->tp_icount));
538
539         tport->tp_msr = 0;
540         tport->tp_shadow_mcr |= (TI_MCR_RTS | TI_MCR_DTR);
541
542         /* start interrupt urb the first time a port is opened on this device */
543         if (tdev->td_open_port_count == 0) {
544                 dbg("%s - start interrupt in urb", __func__);
545                 urb = tdev->td_serial->port[0]->interrupt_in_urb;
546                 if (!urb) {
547                         dev_err(&port->dev, "%s - no interrupt urb\n",
548                                                                 __func__);
549                         status = -EINVAL;
550                         goto release_lock;
551                 }
552                 urb->complete = ti_interrupt_callback;
553                 urb->context = tdev;
554                 urb->dev = dev;
555                 status = usb_submit_urb(urb, GFP_KERNEL);
556                 if (status) {
557                         dev_err(&port->dev,
558                                 "%s - submit interrupt urb failed, %d\n",
559                                         __func__, status);
560                         goto release_lock;
561                 }
562         }
563
564         if (tty)
565                 ti_set_termios(tty, port, tty->termios);
566
567         dbg("%s - sending TI_OPEN_PORT", __func__);
568         status = ti_command_out_sync(tdev, TI_OPEN_PORT,
569                 (__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
570         if (status) {
571                 dev_err(&port->dev, "%s - cannot send open command, %d\n",
572                                                         __func__, status);
573                 goto unlink_int_urb;
574         }
575
576         dbg("%s - sending TI_START_PORT", __func__);
577         status = ti_command_out_sync(tdev, TI_START_PORT,
578                 (__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
579         if (status) {
580                 dev_err(&port->dev, "%s - cannot send start command, %d\n",
581                                                         __func__, status);
582                 goto unlink_int_urb;
583         }
584
585         dbg("%s - sending TI_PURGE_PORT", __func__);
586         status = ti_command_out_sync(tdev, TI_PURGE_PORT,
587                 (__u8)(TI_UART1_PORT + port_number), TI_PURGE_INPUT, NULL, 0);
588         if (status) {
589                 dev_err(&port->dev, "%s - cannot clear input buffers, %d\n",
590                                                         __func__, status);
591                 goto unlink_int_urb;
592         }
593         status = ti_command_out_sync(tdev, TI_PURGE_PORT,
594                 (__u8)(TI_UART1_PORT + port_number), TI_PURGE_OUTPUT, NULL, 0);
595         if (status) {
596                 dev_err(&port->dev, "%s - cannot clear output buffers, %d\n",
597                                                         __func__, status);
598                 goto unlink_int_urb;
599         }
600
601         /* reset the data toggle on the bulk endpoints to work around bug in
602          * host controllers where things get out of sync some times */
603         usb_clear_halt(dev, port->write_urb->pipe);
604         usb_clear_halt(dev, port->read_urb->pipe);
605
606         if (tty)
607                 ti_set_termios(tty, port, tty->termios);
608
609         dbg("%s - sending TI_OPEN_PORT (2)", __func__);
610         status = ti_command_out_sync(tdev, TI_OPEN_PORT,
611                 (__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
612         if (status) {
613                 dev_err(&port->dev, "%s - cannot send open command (2), %d\n",
614                                                         __func__, status);
615                 goto unlink_int_urb;
616         }
617
618         dbg("%s - sending TI_START_PORT (2)", __func__);
619         status = ti_command_out_sync(tdev, TI_START_PORT,
620                 (__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
621         if (status) {
622                 dev_err(&port->dev, "%s - cannot send start command (2), %d\n",
623                                                         __func__, status);
624                 goto unlink_int_urb;
625         }
626
627         /* start read urb */
628         dbg("%s - start read urb", __func__);
629         urb = port->read_urb;
630         if (!urb) {
631                 dev_err(&port->dev, "%s - no read urb\n", __func__);
632                 status = -EINVAL;
633                 goto unlink_int_urb;
634         }
635         tport->tp_read_urb_state = TI_READ_URB_RUNNING;
636         urb->complete = ti_bulk_in_callback;
637         urb->context = tport;
638         urb->dev = dev;
639         status = usb_submit_urb(urb, GFP_KERNEL);
640         if (status) {
641                 dev_err(&port->dev, "%s - submit read urb failed, %d\n",
642                                                         __func__, status);
643                 goto unlink_int_urb;
644         }
645
646         tport->tp_is_open = 1;
647         ++tdev->td_open_port_count;
648
649         goto release_lock;
650
651 unlink_int_urb:
652         if (tdev->td_open_port_count == 0)
653                 usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
654 release_lock:
655         mutex_unlock(&tdev->td_open_close_lock);
656         dbg("%s - exit %d", __func__, status);
657         return status;
658 }
659
660
661 static void ti_close(struct tty_struct *tty, struct usb_serial_port *port,
662                                                         struct file *file)
663 {
664         struct ti_device *tdev;
665         struct ti_port *tport;
666         int port_number;
667         int status;
668         int do_unlock;
669
670         dbg("%s - port %d", __func__, port->number);
671
672         tdev = usb_get_serial_data(port->serial);
673         tport = usb_get_serial_port_data(port);
674         if (tdev == NULL || tport == NULL)
675                 return;
676
677         tport->tp_is_open = 0;
678
679         ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 1);
680
681         usb_kill_urb(port->read_urb);
682         usb_kill_urb(port->write_urb);
683         tport->tp_write_urb_in_use = 0;
684
685         port_number = port->number - port->serial->minor;
686
687         dbg("%s - sending TI_CLOSE_PORT", __func__);
688         status = ti_command_out_sync(tdev, TI_CLOSE_PORT,
689                      (__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
690         if (status)
691                 dev_err(&port->dev,
692                         "%s - cannot send close port command, %d\n"
693                                                         , __func__, status);
694
695         /* if mutex_lock is interrupted, continue anyway */
696         do_unlock = !mutex_lock_interruptible(&tdev->td_open_close_lock);
697         --tport->tp_tdev->td_open_port_count;
698         if (tport->tp_tdev->td_open_port_count <= 0) {
699                 /* last port is closed, shut down interrupt urb */
700                 usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
701                 tport->tp_tdev->td_open_port_count = 0;
702         }
703         if (do_unlock)
704                 mutex_unlock(&tdev->td_open_close_lock);
705
706         dbg("%s - exit", __func__);
707 }
708
709
710 static int ti_write(struct tty_struct *tty, struct usb_serial_port *port,
711                         const unsigned char *data, int count)
712 {
713         struct ti_port *tport = usb_get_serial_port_data(port);
714         unsigned long flags;
715
716         dbg("%s - port %d", __func__, port->number);
717
718         if (count == 0) {
719                 dbg("%s - write request of 0 bytes", __func__);
720                 return 0;
721         }
722
723         if (tport == NULL || !tport->tp_is_open)
724                 return -ENODEV;
725
726         spin_lock_irqsave(&tport->tp_lock, flags);
727         count = ti_buf_put(tport->tp_write_buf, data, count);
728         spin_unlock_irqrestore(&tport->tp_lock, flags);
729
730         ti_send(tport);
731
732         return count;
733 }
734
735
736 static int ti_write_room(struct tty_struct *tty)
737 {
738         struct usb_serial_port *port = tty->driver_data;
739         struct ti_port *tport = usb_get_serial_port_data(port);
740         int room = 0;
741         unsigned long flags;
742
743         dbg("%s - port %d", __func__, port->number);
744
745         if (tport == NULL)
746                 return -ENODEV;
747
748         spin_lock_irqsave(&tport->tp_lock, flags);
749         room = ti_buf_space_avail(tport->tp_write_buf);
750         spin_unlock_irqrestore(&tport->tp_lock, flags);
751
752         dbg("%s - returns %d", __func__, room);
753         return room;
754 }
755
756
757 static int ti_chars_in_buffer(struct tty_struct *tty)
758 {
759         struct usb_serial_port *port = tty->driver_data;
760         struct ti_port *tport = usb_get_serial_port_data(port);
761         int chars = 0;
762         unsigned long flags;
763
764         dbg("%s - port %d", __func__, port->number);
765
766         if (tport == NULL)
767                 return -ENODEV;
768
769         spin_lock_irqsave(&tport->tp_lock, flags);
770         chars = ti_buf_data_avail(tport->tp_write_buf);
771         spin_unlock_irqrestore(&tport->tp_lock, flags);
772
773         dbg("%s - returns %d", __func__, chars);
774         return chars;
775 }
776
777
778 static void ti_throttle(struct tty_struct *tty)
779 {
780         struct usb_serial_port *port = tty->driver_data;
781         struct ti_port *tport = usb_get_serial_port_data(port);
782
783         dbg("%s - port %d", __func__, port->number);
784
785         if (tport == NULL)
786                 return;
787
788         if (I_IXOFF(tty) || C_CRTSCTS(tty))
789                 ti_stop_read(tport, tty);
790
791 }
792
793
794 static void ti_unthrottle(struct tty_struct *tty)
795 {
796         struct usb_serial_port *port = tty->driver_data;
797         struct ti_port *tport = usb_get_serial_port_data(port);
798         int status;
799
800         dbg("%s - port %d", __func__, port->number);
801
802         if (tport == NULL)
803                 return;
804
805         if (I_IXOFF(tty) || C_CRTSCTS(tty)) {
806                 status = ti_restart_read(tport, tty);
807                 if (status)
808                         dev_err(&port->dev, "%s - cannot restart read, %d\n",
809                                                         __func__, status);
810         }
811 }
812
813
814 static int ti_ioctl(struct tty_struct *tty, struct file *file,
815         unsigned int cmd, unsigned long arg)
816 {
817         struct usb_serial_port *port = tty->driver_data;
818         struct ti_port *tport = usb_get_serial_port_data(port);
819         struct async_icount cnow;
820         struct async_icount cprev;
821
822         dbg("%s - port %d, cmd = 0x%04X", __func__, port->number, cmd);
823
824         if (tport == NULL)
825                 return -ENODEV;
826
827         switch (cmd) {
828         case TIOCGSERIAL:
829                 dbg("%s - (%d) TIOCGSERIAL", __func__, port->number);
830                 return ti_get_serial_info(tport,
831                                 (struct serial_struct __user *)arg);
832         case TIOCSSERIAL:
833                 dbg("%s - (%d) TIOCSSERIAL", __func__, port->number);
834                 return ti_set_serial_info(tty, tport,
835                                 (struct serial_struct __user *)arg);
836         case TIOCMIWAIT:
837                 dbg("%s - (%d) TIOCMIWAIT", __func__, port->number);
838                 cprev = tport->tp_icount;
839                 while (1) {
840                         interruptible_sleep_on(&tport->tp_msr_wait);
841                         if (signal_pending(current))
842                                 return -ERESTARTSYS;
843                         cnow = tport->tp_icount;
844                         if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
845                             cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
846                                 return -EIO; /* no change => error */
847                         if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
848                             ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
849                             ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
850                             ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)))
851                                 return 0;
852                         cprev = cnow;
853                 }
854                 break;
855         case TIOCGICOUNT:
856                 dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d",
857                                 __func__, port->number,
858                                 tport->tp_icount.rx, tport->tp_icount.tx);
859                 if (copy_to_user((void __user *)arg, &tport->tp_icount,
860                                         sizeof(tport->tp_icount)))
861                         return -EFAULT;
862                 return 0;
863         }
864         return -ENOIOCTLCMD;
865 }
866
867
868 static void ti_set_termios(struct tty_struct *tty,
869                 struct usb_serial_port *port, struct ktermios *old_termios)
870 {
871         struct ti_port *tport = usb_get_serial_port_data(port);
872         struct ti_uart_config *config;
873         tcflag_t cflag, iflag;
874         int baud;
875         int status;
876         int port_number = port->number - port->serial->minor;
877         unsigned int mcr;
878
879         dbg("%s - port %d", __func__, port->number);
880
881         cflag = tty->termios->c_cflag;
882         iflag = tty->termios->c_iflag;
883
884         dbg("%s - cflag %08x, iflag %08x", __func__, cflag, iflag);
885         dbg("%s - old clfag %08x, old iflag %08x", __func__,
886                                 old_termios->c_cflag, old_termios->c_iflag);
887
888         if (tport == NULL)
889                 return;
890
891         config = kmalloc(sizeof(*config), GFP_KERNEL);
892         if (!config) {
893                 dev_err(&port->dev, "%s - out of memory\n", __func__);
894                 return;
895         }
896
897         config->wFlags = 0;
898
899         /* these flags must be set */
900         config->wFlags |= TI_UART_ENABLE_MS_INTS;
901         config->wFlags |= TI_UART_ENABLE_AUTO_START_DMA;
902         config->bUartMode = (__u8)(tport->tp_uart_mode);
903
904         switch (cflag & CSIZE) {
905         case CS5:
906                     config->bDataBits = TI_UART_5_DATA_BITS;
907                     break;
908         case CS6:
909                     config->bDataBits = TI_UART_6_DATA_BITS;
910                     break;
911         case CS7:
912                     config->bDataBits = TI_UART_7_DATA_BITS;
913                     break;
914         default:
915         case CS8:
916                     config->bDataBits = TI_UART_8_DATA_BITS;
917                     break;
918         }
919
920         /* CMSPAR isn't supported by this driver */
921         tty->termios->c_cflag &= ~CMSPAR;
922
923         if (cflag & PARENB) {
924                 if (cflag & PARODD) {
925                         config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
926                         config->bParity = TI_UART_ODD_PARITY;
927                 } else {
928                         config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
929                         config->bParity = TI_UART_EVEN_PARITY;
930                 }
931         } else {
932                 config->wFlags &= ~TI_UART_ENABLE_PARITY_CHECKING;
933                 config->bParity = TI_UART_NO_PARITY;
934         }
935
936         if (cflag & CSTOPB)
937                 config->bStopBits = TI_UART_2_STOP_BITS;
938         else
939                 config->bStopBits = TI_UART_1_STOP_BITS;
940
941         if (cflag & CRTSCTS) {
942                 /* RTS flow control must be off to drop RTS for baud rate B0 */
943                 if ((cflag & CBAUD) != B0)
944                         config->wFlags |= TI_UART_ENABLE_RTS_IN;
945                 config->wFlags |= TI_UART_ENABLE_CTS_OUT;
946         } else {
947                 tty->hw_stopped = 0;
948                 ti_restart_read(tport, tty);
949         }
950
951         if (I_IXOFF(tty) || I_IXON(tty)) {
952                 config->cXon  = START_CHAR(tty);
953                 config->cXoff = STOP_CHAR(tty);
954
955                 if (I_IXOFF(tty))
956                         config->wFlags |= TI_UART_ENABLE_X_IN;
957                 else
958                         ti_restart_read(tport, tty);
959
960                 if (I_IXON(tty))
961                         config->wFlags |= TI_UART_ENABLE_X_OUT;
962         }
963
964         baud = tty_get_baud_rate(tty);
965         if (!baud)
966                 baud = 9600;
967         if (tport->tp_tdev->td_is_3410)
968                 config->wBaudRate = (__u16)((923077 + baud/2) / baud);
969         else
970                 config->wBaudRate = (__u16)((461538 + baud/2) / baud);
971
972         /* FIXME: Should calculate resulting baud here and report it back */
973         if ((cflag & CBAUD) != B0)
974                 tty_encode_baud_rate(tty, baud, baud);
975
976         dbg("%s - BaudRate=%d, wBaudRate=%d, wFlags=0x%04X, bDataBits=%d, bParity=%d, bStopBits=%d, cXon=%d, cXoff=%d, bUartMode=%d",
977         __func__, baud, config->wBaudRate, config->wFlags, config->bDataBits, config->bParity, config->bStopBits, config->cXon, config->cXoff, config->bUartMode);
978
979         cpu_to_be16s(&config->wBaudRate);
980         cpu_to_be16s(&config->wFlags);
981
982         status = ti_command_out_sync(tport->tp_tdev, TI_SET_CONFIG,
983                 (__u8)(TI_UART1_PORT + port_number), 0, (__u8 *)config,
984                 sizeof(*config));
985         if (status)
986                 dev_err(&port->dev, "%s - cannot set config on port %d, %d\n",
987                                         __func__, port_number, status);
988
989         /* SET_CONFIG asserts RTS and DTR, reset them correctly */
990         mcr = tport->tp_shadow_mcr;
991         /* if baud rate is B0, clear RTS and DTR */
992         if ((cflag & CBAUD) == B0)
993                 mcr &= ~(TI_MCR_DTR | TI_MCR_RTS);
994         status = ti_set_mcr(tport, mcr);
995         if (status)
996                 dev_err(&port->dev,
997                         "%s - cannot set modem control on port %d, %d\n",
998                                                 __func__, port_number, status);
999
1000         kfree(config);
1001 }
1002
1003
1004 static int ti_tiocmget(struct tty_struct *tty, struct file *file)
1005 {
1006         struct usb_serial_port *port = tty->driver_data;
1007         struct ti_port *tport = usb_get_serial_port_data(port);
1008         unsigned int result;
1009         unsigned int msr;
1010         unsigned int mcr;
1011         unsigned long flags;
1012
1013         dbg("%s - port %d", __func__, port->number);
1014
1015         if (tport == NULL)
1016                 return -ENODEV;
1017
1018         spin_lock_irqsave(&tport->tp_lock, flags);
1019         msr = tport->tp_msr;
1020         mcr = tport->tp_shadow_mcr;
1021         spin_unlock_irqrestore(&tport->tp_lock, flags);
1022
1023         result = ((mcr & TI_MCR_DTR) ? TIOCM_DTR : 0)
1024                 | ((mcr & TI_MCR_RTS) ? TIOCM_RTS : 0)
1025                 | ((mcr & TI_MCR_LOOP) ? TIOCM_LOOP : 0)
1026                 | ((msr & TI_MSR_CTS) ? TIOCM_CTS : 0)
1027                 | ((msr & TI_MSR_CD) ? TIOCM_CAR : 0)
1028                 | ((msr & TI_MSR_RI) ? TIOCM_RI : 0)
1029                 | ((msr & TI_MSR_DSR) ? TIOCM_DSR : 0);
1030
1031         dbg("%s - 0x%04X", __func__, result);
1032
1033         return result;
1034 }
1035
1036
1037 static int ti_tiocmset(struct tty_struct *tty, struct file *file,
1038         unsigned int set, unsigned int clear)
1039 {
1040         struct usb_serial_port *port = tty->driver_data;
1041         struct ti_port *tport = usb_get_serial_port_data(port);
1042         unsigned int mcr;
1043         unsigned long flags;
1044
1045         dbg("%s - port %d", __func__, port->number);
1046
1047         if (tport == NULL)
1048                 return -ENODEV;
1049
1050         spin_lock_irqsave(&tport->tp_lock, flags);
1051         mcr = tport->tp_shadow_mcr;
1052
1053         if (set & TIOCM_RTS)
1054                 mcr |= TI_MCR_RTS;
1055         if (set & TIOCM_DTR)
1056                 mcr |= TI_MCR_DTR;
1057         if (set & TIOCM_LOOP)
1058                 mcr |= TI_MCR_LOOP;
1059
1060         if (clear & TIOCM_RTS)
1061                 mcr &= ~TI_MCR_RTS;
1062         if (clear & TIOCM_DTR)
1063                 mcr &= ~TI_MCR_DTR;
1064         if (clear & TIOCM_LOOP)
1065                 mcr &= ~TI_MCR_LOOP;
1066         spin_unlock_irqrestore(&tport->tp_lock, flags);
1067
1068         return ti_set_mcr(tport, mcr);
1069 }
1070
1071
1072 static void ti_break(struct tty_struct *tty, int break_state)
1073 {
1074         struct usb_serial_port *port = tty->driver_data;
1075         struct ti_port *tport = usb_get_serial_port_data(port);
1076         int status;
1077
1078         dbg("%s - state = %d", __func__, break_state);
1079
1080         if (tport == NULL)
1081                 return;
1082
1083         ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 0);
1084
1085         status = ti_write_byte(tport->tp_tdev,
1086                 tport->tp_uart_base_addr + TI_UART_OFFSET_LCR,
1087                 TI_LCR_BREAK, break_state == -1 ? TI_LCR_BREAK : 0);
1088
1089         if (status)
1090                 dbg("%s - error setting break, %d", __func__, status);
1091 }
1092
1093
1094 static void ti_interrupt_callback(struct urb *urb)
1095 {
1096         struct ti_device *tdev = urb->context;
1097         struct usb_serial_port *port;
1098         struct usb_serial *serial = tdev->td_serial;
1099         struct ti_port *tport;
1100         struct device *dev = &urb->dev->dev;
1101         unsigned char *data = urb->transfer_buffer;
1102         int length = urb->actual_length;
1103         int port_number;
1104         int function;
1105         int status = urb->status;
1106         int retval;
1107         __u8 msr;
1108
1109         dbg("%s", __func__);
1110
1111         switch (status) {
1112         case 0:
1113                 break;
1114         case -ECONNRESET:
1115         case -ENOENT:
1116         case -ESHUTDOWN:
1117                 dbg("%s - urb shutting down, %d", __func__, status);
1118                 tdev->td_urb_error = 1;
1119                 return;
1120         default:
1121                 dev_err(dev, "%s - nonzero urb status, %d\n",
1122                         __func__, status);
1123                 tdev->td_urb_error = 1;
1124                 goto exit;
1125         }
1126
1127         if (length != 2) {
1128                 dbg("%s - bad packet size, %d", __func__, length);
1129                 goto exit;
1130         }
1131
1132         if (data[0] == TI_CODE_HARDWARE_ERROR) {
1133                 dev_err(dev, "%s - hardware error, %d\n", __func__, data[1]);
1134                 goto exit;
1135         }
1136
1137         port_number = TI_GET_PORT_FROM_CODE(data[0]);
1138         function = TI_GET_FUNC_FROM_CODE(data[0]);
1139
1140         dbg("%s - port_number %d, function %d, data 0x%02X",
1141                                 __func__, port_number, function, data[1]);
1142
1143         if (port_number >= serial->num_ports) {
1144                 dev_err(dev, "%s - bad port number, %d\n",
1145                                                 __func__, port_number);
1146                 goto exit;
1147         }
1148
1149         port = serial->port[port_number];
1150
1151         tport = usb_get_serial_port_data(port);
1152         if (!tport)
1153                 goto exit;
1154
1155         switch (function) {
1156         case TI_CODE_DATA_ERROR:
1157                 dev_err(dev, "%s - DATA ERROR, port %d, data 0x%02X\n",
1158                                         __func__, port_number, data[1]);
1159                 break;
1160
1161         case TI_CODE_MODEM_STATUS:
1162                 msr = data[1];
1163                 dbg("%s - port %d, msr 0x%02X", __func__, port_number, msr);
1164                 ti_handle_new_msr(tport, msr);
1165                 break;
1166
1167         default:
1168                 dev_err(dev, "%s - unknown interrupt code, 0x%02X\n",
1169                                                         __func__, data[1]);
1170                 break;
1171         }
1172
1173 exit:
1174         retval = usb_submit_urb(urb, GFP_ATOMIC);
1175         if (retval)
1176                 dev_err(dev, "%s - resubmit interrupt urb failed, %d\n",
1177                         __func__, retval);
1178 }
1179
1180
1181 static void ti_bulk_in_callback(struct urb *urb)
1182 {
1183         struct ti_port *tport = urb->context;
1184         struct usb_serial_port *port = tport->tp_port;
1185         struct device *dev = &urb->dev->dev;
1186         int status = urb->status;
1187         int retval = 0;
1188         struct tty_struct *tty;
1189
1190         dbg("%s", __func__);
1191
1192         switch (status) {
1193         case 0:
1194                 break;
1195         case -ECONNRESET:
1196         case -ENOENT:
1197         case -ESHUTDOWN:
1198                 dbg("%s - urb shutting down, %d", __func__, status);
1199                 tport->tp_tdev->td_urb_error = 1;
1200                 wake_up_interruptible(&tport->tp_write_wait);
1201                 return;
1202         default:
1203                 dev_err(dev, "%s - nonzero urb status, %d\n",
1204                         __func__, status);
1205                 tport->tp_tdev->td_urb_error = 1;
1206                 wake_up_interruptible(&tport->tp_write_wait);
1207         }
1208
1209         if (status == -EPIPE)
1210                 goto exit;
1211
1212         if (status) {
1213                 dev_err(dev, "%s - stopping read!\n", __func__);
1214                 return;
1215         }
1216
1217         tty = tty_port_tty_get(&port->port);
1218         if (tty) {
1219                 if (urb->actual_length) {
1220                         usb_serial_debug_data(debug, dev, __func__,
1221                                 urb->actual_length, urb->transfer_buffer);
1222
1223                         if (!tport->tp_is_open)
1224                                 dbg("%s - port closed, dropping data",
1225                                         __func__);
1226                         else
1227                                 ti_recv(&urb->dev->dev, tty,
1228                                                 urb->transfer_buffer,
1229                                                 urb->actual_length);
1230                         spin_lock(&tport->tp_lock);
1231                         tport->tp_icount.rx += urb->actual_length;
1232                         spin_unlock(&tport->tp_lock);
1233                 }
1234                 tty_kref_put(tty);
1235         }
1236
1237 exit:
1238         /* continue to read unless stopping */
1239         spin_lock(&tport->tp_lock);
1240         if (tport->tp_read_urb_state == TI_READ_URB_RUNNING) {
1241                 urb->dev = port->serial->dev;
1242                 retval = usb_submit_urb(urb, GFP_ATOMIC);
1243         } else if (tport->tp_read_urb_state == TI_READ_URB_STOPPING) {
1244                 tport->tp_read_urb_state = TI_READ_URB_STOPPED;
1245         }
1246         spin_unlock(&tport->tp_lock);
1247         if (retval)
1248                 dev_err(dev, "%s - resubmit read urb failed, %d\n",
1249                         __func__, retval);
1250 }
1251
1252
1253 static void ti_bulk_out_callback(struct urb *urb)
1254 {
1255         struct ti_port *tport = urb->context;
1256         struct usb_serial_port *port = tport->tp_port;
1257         struct device *dev = &urb->dev->dev;
1258         int status = urb->status;
1259
1260         dbg("%s - port %d", __func__, port->number);
1261
1262         tport->tp_write_urb_in_use = 0;
1263
1264         switch (status) {
1265         case 0:
1266                 break;
1267         case -ECONNRESET:
1268         case -ENOENT:
1269         case -ESHUTDOWN:
1270                 dbg("%s - urb shutting down, %d", __func__, status);
1271                 tport->tp_tdev->td_urb_error = 1;
1272                 wake_up_interruptible(&tport->tp_write_wait);
1273                 return;
1274         default:
1275                 dev_err(dev, "%s - nonzero urb status, %d\n",
1276                         __func__, status);
1277                 tport->tp_tdev->td_urb_error = 1;
1278                 wake_up_interruptible(&tport->tp_write_wait);
1279         }
1280
1281         /* send any buffered data */
1282         ti_send(tport);
1283 }
1284
1285
1286 static void ti_recv(struct device *dev, struct tty_struct *tty,
1287         unsigned char *data, int length)
1288 {
1289         int cnt;
1290
1291         do {
1292                 cnt = tty_buffer_request_room(tty, length);
1293                 if (cnt < length) {
1294                         dev_err(dev, "%s - dropping data, %d bytes lost\n",
1295                                                 __func__, length - cnt);
1296                         if (cnt == 0)
1297                                 break;
1298                 }
1299                 tty_insert_flip_string(tty, data, cnt);
1300                 tty_flip_buffer_push(tty);
1301                 data += cnt;
1302                 length -= cnt;
1303         } while (length > 0);
1304
1305 }
1306
1307
1308 static void ti_send(struct ti_port *tport)
1309 {
1310         int count, result;
1311         struct usb_serial_port *port = tport->tp_port;
1312         struct tty_struct *tty = tty_port_tty_get(&port->port); /* FIXME */
1313         unsigned long flags;
1314
1315
1316         dbg("%s - port %d", __func__, port->number);
1317
1318         spin_lock_irqsave(&tport->tp_lock, flags);
1319
1320         if (tport->tp_write_urb_in_use)
1321                 goto unlock;
1322
1323         count = ti_buf_get(tport->tp_write_buf,
1324                                 port->write_urb->transfer_buffer,
1325                                 port->bulk_out_size);
1326
1327         if (count == 0)
1328                 goto unlock;
1329
1330         tport->tp_write_urb_in_use = 1;
1331
1332         spin_unlock_irqrestore(&tport->tp_lock, flags);
1333
1334         usb_serial_debug_data(debug, &port->dev, __func__, count,
1335                                         port->write_urb->transfer_buffer);
1336
1337         usb_fill_bulk_urb(port->write_urb, port->serial->dev,
1338                            usb_sndbulkpipe(port->serial->dev,
1339                                             port->bulk_out_endpointAddress),
1340                            port->write_urb->transfer_buffer, count,
1341                            ti_bulk_out_callback, tport);
1342
1343         result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1344         if (result) {
1345                 dev_err(&port->dev, "%s - submit write urb failed, %d\n",
1346                                                         __func__, result);
1347                 tport->tp_write_urb_in_use = 0;
1348                 /* TODO: reschedule ti_send */
1349         } else {
1350                 spin_lock_irqsave(&tport->tp_lock, flags);
1351                 tport->tp_icount.tx += count;
1352                 spin_unlock_irqrestore(&tport->tp_lock, flags);
1353         }
1354
1355         /* more room in the buffer for new writes, wakeup */
1356         if (tty)
1357                 tty_wakeup(tty);
1358         tty_kref_put(tty);
1359         wake_up_interruptible(&tport->tp_write_wait);
1360         return;
1361 unlock:
1362         spin_unlock_irqrestore(&tport->tp_lock, flags);
1363         tty_kref_put(tty);
1364         return;
1365 }
1366
1367
1368 static int ti_set_mcr(struct ti_port *tport, unsigned int mcr)
1369 {
1370         unsigned long flags;
1371         int status;
1372
1373         status = ti_write_byte(tport->tp_tdev,
1374                 tport->tp_uart_base_addr + TI_UART_OFFSET_MCR,
1375                 TI_MCR_RTS | TI_MCR_DTR | TI_MCR_LOOP, mcr);
1376
1377         spin_lock_irqsave(&tport->tp_lock, flags);
1378         if (!status)
1379                 tport->tp_shadow_mcr = mcr;
1380         spin_unlock_irqrestore(&tport->tp_lock, flags);
1381
1382         return status;
1383 }
1384
1385
1386 static int ti_get_lsr(struct ti_port *tport)
1387 {
1388         int size, status;
1389         struct ti_device *tdev = tport->tp_tdev;
1390         struct usb_serial_port *port = tport->tp_port;
1391         int port_number = port->number - port->serial->minor;
1392         struct ti_port_status *data;
1393
1394         dbg("%s - port %d", __func__, port->number);
1395
1396         size = sizeof(struct ti_port_status);
1397         data = kmalloc(size, GFP_KERNEL);
1398         if (!data) {
1399                 dev_err(&port->dev, "%s - out of memory\n", __func__);
1400                 return -ENOMEM;
1401         }
1402
1403         status = ti_command_in_sync(tdev, TI_GET_PORT_STATUS,
1404                 (__u8)(TI_UART1_PORT+port_number), 0, (__u8 *)data, size);
1405         if (status) {
1406                 dev_err(&port->dev,
1407                         "%s - get port status command failed, %d\n",
1408                                                         __func__, status);
1409                 goto free_data;
1410         }
1411
1412         dbg("%s - lsr 0x%02X", __func__, data->bLSR);
1413
1414         tport->tp_lsr = data->bLSR;
1415
1416 free_data:
1417         kfree(data);
1418         return status;
1419 }
1420
1421
1422 static int ti_get_serial_info(struct ti_port *tport,
1423         struct serial_struct __user *ret_arg)
1424 {
1425         struct usb_serial_port *port = tport->tp_port;
1426         struct serial_struct ret_serial;
1427
1428         if (!ret_arg)
1429                 return -EFAULT;
1430
1431         memset(&ret_serial, 0, sizeof(ret_serial));
1432
1433         ret_serial.type = PORT_16550A;
1434         ret_serial.line = port->serial->minor;
1435         ret_serial.port = port->number - port->serial->minor;
1436         ret_serial.flags = tport->tp_flags;
1437         ret_serial.xmit_fifo_size = TI_WRITE_BUF_SIZE;
1438         ret_serial.baud_base = tport->tp_tdev->td_is_3410 ? 921600 : 460800;
1439         ret_serial.closing_wait = tport->tp_closing_wait;
1440
1441         if (copy_to_user(ret_arg, &ret_serial, sizeof(*ret_arg)))
1442                 return -EFAULT;
1443
1444         return 0;
1445 }
1446
1447
1448 static int ti_set_serial_info(struct tty_struct *tty, struct ti_port *tport,
1449         struct serial_struct __user *new_arg)
1450 {
1451         struct serial_struct new_serial;
1452
1453         if (copy_from_user(&new_serial, new_arg, sizeof(new_serial)))
1454                 return -EFAULT;
1455
1456         tport->tp_flags = new_serial.flags & TI_SET_SERIAL_FLAGS;
1457         tty->low_latency = (tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1458         tport->tp_closing_wait = new_serial.closing_wait;
1459
1460         return 0;
1461 }
1462
1463
1464 static void ti_handle_new_msr(struct ti_port *tport, __u8 msr)
1465 {
1466         struct async_icount *icount;
1467         struct tty_struct *tty;
1468         unsigned long flags;
1469
1470         dbg("%s - msr 0x%02X", __func__, msr);
1471
1472         if (msr & TI_MSR_DELTA_MASK) {
1473                 spin_lock_irqsave(&tport->tp_lock, flags);
1474                 icount = &tport->tp_icount;
1475                 if (msr & TI_MSR_DELTA_CTS)
1476                         icount->cts++;
1477                 if (msr & TI_MSR_DELTA_DSR)
1478                         icount->dsr++;
1479                 if (msr & TI_MSR_DELTA_CD)
1480                         icount->dcd++;
1481                 if (msr & TI_MSR_DELTA_RI)
1482                         icount->rng++;
1483                 wake_up_interruptible(&tport->tp_msr_wait);
1484                 spin_unlock_irqrestore(&tport->tp_lock, flags);
1485         }
1486
1487         tport->tp_msr = msr & TI_MSR_MASK;
1488
1489         /* handle CTS flow control */
1490         tty = tty_port_tty_get(&tport->tp_port->port);
1491         if (tty && C_CRTSCTS(tty)) {
1492                 if (msr & TI_MSR_CTS) {
1493                         tty->hw_stopped = 0;
1494                         tty_wakeup(tty);
1495                 } else {
1496                         tty->hw_stopped = 1;
1497                 }
1498         }
1499         tty_kref_put(tty);
1500 }
1501
1502
1503 static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush)
1504 {
1505         struct ti_device *tdev = tport->tp_tdev;
1506         struct usb_serial_port *port = tport->tp_port;
1507         wait_queue_t wait;
1508
1509         dbg("%s - port %d", __func__, port->number);
1510
1511         spin_lock_irq(&tport->tp_lock);
1512
1513         /* wait for data to drain from the buffer */
1514         tdev->td_urb_error = 0;
1515         init_waitqueue_entry(&wait, current);
1516         add_wait_queue(&tport->tp_write_wait, &wait);
1517         for (;;) {
1518                 set_current_state(TASK_INTERRUPTIBLE);
1519                 if (ti_buf_data_avail(tport->tp_write_buf) == 0
1520                 || timeout == 0 || signal_pending(current)
1521                 || tdev->td_urb_error
1522                 || port->serial->disconnected)  /* disconnect */
1523                         break;
1524                 spin_unlock_irq(&tport->tp_lock);
1525                 timeout = schedule_timeout(timeout);
1526                 spin_lock_irq(&tport->tp_lock);
1527         }
1528         set_current_state(TASK_RUNNING);
1529         remove_wait_queue(&tport->tp_write_wait, &wait);
1530
1531         /* flush any remaining data in the buffer */
1532         if (flush)
1533                 ti_buf_clear(tport->tp_write_buf);
1534
1535         spin_unlock_irq(&tport->tp_lock);
1536
1537         mutex_lock(&port->serial->disc_mutex);
1538         /* wait for data to drain from the device */
1539         /* wait for empty tx register, plus 20 ms */
1540         timeout += jiffies;
1541         tport->tp_lsr &= ~TI_LSR_TX_EMPTY;
1542         while ((long)(jiffies - timeout) < 0 && !signal_pending(current)
1543         && !(tport->tp_lsr&TI_LSR_TX_EMPTY) && !tdev->td_urb_error
1544         && !port->serial->disconnected) {
1545                 if (ti_get_lsr(tport))
1546                         break;
1547                 mutex_unlock(&port->serial->disc_mutex);
1548                 msleep_interruptible(20);
1549                 mutex_lock(&port->serial->disc_mutex);
1550         }
1551         mutex_unlock(&port->serial->disc_mutex);
1552 }
1553
1554
1555 static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty)
1556 {
1557         unsigned long flags;
1558
1559         spin_lock_irqsave(&tport->tp_lock, flags);
1560
1561         if (tport->tp_read_urb_state == TI_READ_URB_RUNNING)
1562                 tport->tp_read_urb_state = TI_READ_URB_STOPPING;
1563
1564         spin_unlock_irqrestore(&tport->tp_lock, flags);
1565 }
1566
1567
1568 static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty)
1569 {
1570         struct urb *urb;
1571         int status = 0;
1572         unsigned long flags;
1573
1574         spin_lock_irqsave(&tport->tp_lock, flags);
1575
1576         if (tport->tp_read_urb_state == TI_READ_URB_STOPPED) {
1577                 tport->tp_read_urb_state = TI_READ_URB_RUNNING;
1578                 urb = tport->tp_port->read_urb;
1579                 spin_unlock_irqrestore(&tport->tp_lock, flags);
1580                 urb->complete = ti_bulk_in_callback;
1581                 urb->context = tport;
1582                 urb->dev = tport->tp_port->serial->dev;
1583                 status = usb_submit_urb(urb, GFP_KERNEL);
1584         } else  {
1585                 tport->tp_read_urb_state = TI_READ_URB_RUNNING;
1586                 spin_unlock_irqrestore(&tport->tp_lock, flags);
1587         }
1588
1589         return status;
1590 }
1591
1592
1593 static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
1594         __u16 moduleid, __u16 value, __u8 *data, int size)
1595 {
1596         int status;
1597
1598         status = usb_control_msg(tdev->td_serial->dev,
1599                 usb_sndctrlpipe(tdev->td_serial->dev, 0), command,
1600                 (USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT),
1601                 value, moduleid, data, size, 1000);
1602
1603         if (status == size)
1604                 status = 0;
1605
1606         if (status > 0)
1607                 status = -ECOMM;
1608
1609         return status;
1610 }
1611
1612
1613 static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
1614         __u16 moduleid, __u16 value, __u8 *data, int size)
1615 {
1616         int status;
1617
1618         status = usb_control_msg(tdev->td_serial->dev,
1619                 usb_rcvctrlpipe(tdev->td_serial->dev, 0), command,
1620                 (USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN),
1621                 value, moduleid, data, size, 1000);
1622
1623         if (status == size)
1624                 status = 0;
1625
1626         if (status > 0)
1627                 status = -ECOMM;
1628
1629         return status;
1630 }
1631
1632
1633 static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
1634         __u8 mask, __u8 byte)
1635 {
1636         int status;
1637         unsigned int size;
1638         struct ti_write_data_bytes *data;
1639         struct device *dev = &tdev->td_serial->dev->dev;
1640
1641         dbg("%s - addr 0x%08lX, mask 0x%02X, byte 0x%02X",
1642                                         __func__, addr, mask, byte);
1643
1644         size = sizeof(struct ti_write_data_bytes) + 2;
1645         data = kmalloc(size, GFP_KERNEL);
1646         if (!data) {
1647                 dev_err(dev, "%s - out of memory\n", __func__);
1648                 return -ENOMEM;
1649         }
1650
1651         data->bAddrType = TI_RW_DATA_ADDR_XDATA;
1652         data->bDataType = TI_RW_DATA_BYTE;
1653         data->bDataCounter = 1;
1654         data->wBaseAddrHi = cpu_to_be16(addr>>16);
1655         data->wBaseAddrLo = cpu_to_be16(addr);
1656         data->bData[0] = mask;
1657         data->bData[1] = byte;
1658
1659         status = ti_command_out_sync(tdev, TI_WRITE_DATA, TI_RAM_PORT, 0,
1660                 (__u8 *)data, size);
1661
1662         if (status < 0)
1663                 dev_err(dev, "%s - failed, %d\n", __func__, status);
1664
1665         kfree(data);
1666
1667         return status;
1668 }
1669
1670 static int ti_do_download(struct usb_device *dev, int pipe,
1671                                                 u8 *buffer, int size)
1672 {
1673         int pos;
1674         u8 cs = 0;
1675         int done;
1676         struct ti_firmware_header *header;
1677         int status;
1678         int len;
1679
1680         for (pos = sizeof(struct ti_firmware_header); pos < size; pos++)
1681                 cs = (__u8)(cs + buffer[pos]);
1682
1683         header = (struct ti_firmware_header *)buffer;
1684         header->wLength = cpu_to_le16((__u16)(size
1685                                         - sizeof(struct ti_firmware_header)));
1686         header->bCheckSum = cs;
1687
1688         dbg("%s - downloading firmware", __func__);
1689         for (pos = 0; pos < size; pos += done) {
1690                 len = min(size - pos, TI_DOWNLOAD_MAX_PACKET_SIZE);
1691                 status = usb_bulk_msg(dev, pipe, buffer + pos, len,
1692                                                                 &done, 1000);
1693                 if (status)
1694                         break;
1695         }
1696         return status;
1697 }
1698
1699 static int ti_download_firmware(struct ti_device *tdev)
1700 {
1701         int status;
1702         int buffer_size;
1703         __u8 *buffer;
1704         struct usb_device *dev = tdev->td_serial->dev;
1705         unsigned int pipe = usb_sndbulkpipe(dev,
1706                 tdev->td_serial->port[0]->bulk_out_endpointAddress);
1707         const struct firmware *fw_p;
1708         char buf[32];
1709
1710         /* try ID specific firmware first, then try generic firmware */
1711         sprintf(buf, "ti_usb-v%04x-p%04x.fw", dev->descriptor.idVendor,
1712             dev->descriptor.idProduct);
1713         if ((status = request_firmware(&fw_p, buf, &dev->dev)) != 0) {
1714                 buf[0] = '\0';
1715                 if (dev->descriptor.idVendor == MTS_VENDOR_ID) {
1716                         switch (dev->descriptor.idProduct) {
1717                         case MTS_CDMA_PRODUCT_ID:
1718                                 strcpy(buf, "mts_cdma.fw");
1719                                 break;
1720                         case MTS_GSM_PRODUCT_ID:
1721                                 strcpy(buf, "mts_gsm.fw");
1722                                 break;
1723                         case MTS_EDGE_PRODUCT_ID:
1724                                 strcpy(buf, "mts_edge.fw");
1725                                 break;
1726                         }
1727                 }
1728                 if (buf[0] == '\0') {
1729                         if (tdev->td_is_3410)
1730                                 strcpy(buf, "ti_3410.fw");
1731                         else
1732                                 strcpy(buf, "ti_5052.fw");
1733                 }
1734                 status = request_firmware(&fw_p, buf, &dev->dev);
1735         }
1736         if (status) {
1737                 dev_err(&dev->dev, "%s - firmware not found\n", __func__);
1738                 return -ENOENT;
1739         }
1740         if (fw_p->size > TI_FIRMWARE_BUF_SIZE) {
1741                 dev_err(&dev->dev, "%s - firmware too large\n", __func__);
1742                 return -ENOENT;
1743         }
1744
1745         buffer_size = TI_FIRMWARE_BUF_SIZE + sizeof(struct ti_firmware_header);
1746         buffer = kmalloc(buffer_size, GFP_KERNEL);
1747         if (buffer) {
1748                 memcpy(buffer, fw_p->data, fw_p->size);
1749                 memset(buffer + fw_p->size, 0xff, buffer_size - fw_p->size);
1750                 status = ti_do_download(dev, pipe, buffer, fw_p->size);
1751                 kfree(buffer);
1752         } else {
1753                 status = -ENOMEM;
1754         }
1755         release_firmware(fw_p);
1756         if (status) {
1757                 dev_err(&dev->dev, "%s - error downloading firmware, %d\n",
1758                                                         __func__, status);
1759                 return status;
1760         }
1761
1762         dbg("%s - download successful", __func__);
1763
1764         return 0;
1765 }
1766
1767
1768 /* Circular Buffer Functions */
1769
1770 /*
1771  * ti_buf_alloc
1772  *
1773  * Allocate a circular buffer and all associated memory.
1774  */
1775
1776 static struct circ_buf *ti_buf_alloc(void)
1777 {
1778         struct circ_buf *cb;
1779
1780         cb = kmalloc(sizeof(struct circ_buf), GFP_KERNEL);
1781         if (cb == NULL)
1782                 return NULL;
1783
1784         cb->buf = kmalloc(TI_WRITE_BUF_SIZE, GFP_KERNEL);
1785         if (cb->buf == NULL) {
1786                 kfree(cb);
1787                 return NULL;
1788         }
1789
1790         ti_buf_clear(cb);
1791
1792         return cb;
1793 }
1794
1795
1796 /*
1797  * ti_buf_free
1798  *
1799  * Free the buffer and all associated memory.
1800  */
1801
1802 static void ti_buf_free(struct circ_buf *cb)
1803 {
1804         kfree(cb->buf);
1805         kfree(cb);
1806 }
1807
1808
1809 /*
1810  * ti_buf_clear
1811  *
1812  * Clear out all data in the circular buffer.
1813  */
1814
1815 static void ti_buf_clear(struct circ_buf *cb)
1816 {
1817         cb->head = cb->tail = 0;
1818 }
1819
1820
1821 /*
1822  * ti_buf_data_avail
1823  *
1824  * Return the number of bytes of data available in the circular
1825  * buffer.
1826  */
1827
1828 static int ti_buf_data_avail(struct circ_buf *cb)
1829 {
1830         return CIRC_CNT(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1831 }
1832
1833
1834 /*
1835  * ti_buf_space_avail
1836  *
1837  * Return the number of bytes of space available in the circular
1838  * buffer.
1839  */
1840
1841 static int ti_buf_space_avail(struct circ_buf *cb)
1842 {
1843         return CIRC_SPACE(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1844 }
1845
1846
1847 /*
1848  * ti_buf_put
1849  *
1850  * Copy data data from a user buffer and put it into the circular buffer.
1851  * Restrict to the amount of space available.
1852  *
1853  * Return the number of bytes copied.
1854  */
1855
1856 static int ti_buf_put(struct circ_buf *cb, const char *buf, int count)
1857 {
1858         int c, ret = 0;
1859
1860         while (1) {
1861                 c = CIRC_SPACE_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1862                 if (count < c)
1863                         c = count;
1864                 if (c <= 0)
1865                         break;
1866                 memcpy(cb->buf + cb->head, buf, c);
1867                 cb->head = (cb->head + c) & (TI_WRITE_BUF_SIZE-1);
1868                 buf += c;
1869                 count -= c;
1870                 ret += c;
1871         }
1872
1873         return ret;
1874 }
1875
1876
1877 /*
1878  * ti_buf_get
1879  *
1880  * Get data from the circular buffer and copy to the given buffer.
1881  * Restrict to the amount of data available.
1882  *
1883  * Return the number of bytes copied.
1884  */
1885
1886 static int ti_buf_get(struct circ_buf *cb, char *buf, int count)
1887 {
1888         int c, ret = 0;
1889
1890         while (1) {
1891                 c = CIRC_CNT_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
1892                 if (count < c)
1893                         c = count;
1894                 if (c <= 0)
1895                         break;
1896                 memcpy(buf, cb->buf + cb->tail, c);
1897                 cb->tail = (cb->tail + c) & (TI_WRITE_BUF_SIZE-1);
1898                 buf += c;
1899                 count -= c;
1900                 ret += c;
1901         }
1902
1903         return ret;
1904 }