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 }
1905