1 /* 2 * USB Empeg empeg-car player driver 3 * 4 * Copyright (C) 2000, 2001 5 * Gary Brubaker (xavyer@ix.netcom.com) 6 * 7 * Copyright (C) 1999 - 2001 8 * Greg Kroah-Hartman (greg@kroah.com) 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License, as published by 12 * the Free Software Foundation, version 2. 13 * 14 * See Documentation/usb/usb-serial.txt for more information on using this 15 * driver 16 * 17 * (07/16/2001) gb 18 * remove unused code in empeg_close() (thanks to Oliver Neukum for 19 * pointing this out) and rewrote empeg_set_termios(). 20 * 21 * (05/30/2001) gkh 22 * switched from using spinlock to a semaphore, which fixes lots of 23 * problems. 24 * 25 * (04/08/2001) gb 26 * Identify version on module load. 27 * 28 * (01/22/2001) gb 29 * Added write_room() and chars_in_buffer() support. 30 * 31 * (12/21/2000) gb 32 * Moved termio stuff inside the port->active check. 33 * Moved MOD_DEC_USE_COUNT to end of empeg_close(). 34 * 35 * (12/03/2000) gb 36 * Added tty->ldisc.set_termios(port, tty, NULL) to empeg_open(). 37 * This notifies the tty driver that the termios have changed. 38 * 39 * (11/13/2000) gb 40 * Moved tty->low_latency = 1 from empeg_read_bulk_callback() to 41 * empeg_open() (It only needs to be set once - Doh!) 42 * 43 * (11/11/2000) gb 44 * Updated to work with id_table structure. 45 * 46 * (11/04/2000) gb 47 * Forked this from visor.c, and hacked it up to work with an 48 * Empeg ltd. empeg-car player. Constructive criticism welcomed. 49 * I would like to say, 'Thank You' to Greg Kroah-Hartman for the 50 * use of his code, and for his guidance, advice and patience. :) 51 * A 'Thank You' is in order for John Ripley of Empeg ltd for his 52 * advice, and patience too. 53 * 54 */ 55 56 #include <linux/kernel.h> 57 #include <linux/errno.h> 58 #include <linux/init.h> 59 #include <linux/slab.h> 60 #include <linux/tty.h> 61 #include <linux/tty_driver.h> 62 #include <linux/tty_flip.h> 63 #include <linux/module.h> 64 #include <linux/spinlock.h> 65 #include <linux/uaccess.h> 66 #include <linux/usb.h> 67 #include <linux/usb/serial.h> 68 69 static int debug; 70 71 /* 72 * Version Information 73 */ 74 #define DRIVER_VERSION "v1.2" 75 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>" 76 #define DRIVER_DESC "USB Empeg Mark I/II Driver" 77 78 #define EMPEG_VENDOR_ID 0x084f 79 #define EMPEG_PRODUCT_ID 0x0001 80 81 /* function prototypes for an empeg-car player */ 82 static int empeg_open(struct tty_struct *tty, struct usb_serial_port *port); 83 static void empeg_close(struct usb_serial_port *port); 84 static int empeg_write(struct tty_struct *tty, struct usb_serial_port *port, 85 const unsigned char *buf, 86 int count); 87 static int empeg_write_room(struct tty_struct *tty); 88 static int empeg_chars_in_buffer(struct tty_struct *tty); 89 static void empeg_throttle(struct tty_struct *tty); 90 static void empeg_unthrottle(struct tty_struct *tty); 91 static int empeg_startup(struct usb_serial *serial); 92 static void empeg_init_termios(struct tty_struct *tty); 93 static void empeg_write_bulk_callback(struct urb *urb); 94 static void empeg_read_bulk_callback(struct urb *urb); 95 96 static const struct usb_device_id id_table[] = { 97 { USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) }, 98 { } /* Terminating entry */ 99 }; 100 101 MODULE_DEVICE_TABLE(usb, id_table); 102 103 static struct usb_driver empeg_driver = { 104 .name = "empeg", 105 .probe = usb_serial_probe, 106 .disconnect = usb_serial_disconnect, 107 .id_table = id_table, 108 .no_dynamic_id = 1, 109 }; 110 111 static struct usb_serial_driver empeg_device = { 112 .driver = { 113 .owner = THIS_MODULE, 114 .name = "empeg", 115 }, 116 .id_table = id_table, 117 .usb_driver = &empeg_driver, 118 .num_ports = 1, 119 .open = empeg_open, 120 .close = empeg_close, 121 .throttle = empeg_throttle, 122 .unthrottle = empeg_unthrottle, 123 .attach = empeg_startup, 124 .init_termios = empeg_init_termios, 125 .write = empeg_write, 126 .write_room = empeg_write_room, 127 .chars_in_buffer = empeg_chars_in_buffer, 128 .write_bulk_callback = empeg_write_bulk_callback, 129 .read_bulk_callback = empeg_read_bulk_callback, 130 }; 131 132 #define NUM_URBS 16 133 #define URB_TRANSFER_BUFFER_SIZE 4096 134 135 static struct urb *write_urb_pool[NUM_URBS]; 136 static spinlock_t write_urb_pool_lock; 137 static int bytes_in; 138 static int bytes_out; 139 140 /****************************************************************************** 141 * Empeg specific driver functions 142 ******************************************************************************/ 143 static int empeg_open(struct tty_struct *tty,struct usb_serial_port *port) 144 { 145 struct usb_serial *serial = port->serial; 146 int result = 0; 147 148 dbg("%s - port %d", __func__, port->number); 149 150 bytes_in = 0; 151 bytes_out = 0; 152 153 /* Start reading from the device */ 154 usb_fill_bulk_urb( 155 port->read_urb, 156 serial->dev, 157 usb_rcvbulkpipe(serial->dev, 158 port->bulk_in_endpointAddress), 159 port->read_urb->transfer_buffer, 160 port->read_urb->transfer_buffer_length, 161 empeg_read_bulk_callback, 162 port); 163 164 result = usb_submit_urb(port->read_urb, GFP_KERNEL); 165 166 if (result) 167 dev_err(&port->dev, 168 "%s - failed submitting read urb, error %d\n", 169 __func__, result); 170 171 return result; 172 } 173 174 175 static void empeg_close(struct usb_serial_port *port) 176 { 177 dbg("%s - port %d", __func__, port->number); 178 179 /* shutdown our bulk read */ 180 usb_kill_urb(port->read_urb); 181 /* Uncomment the following line if you want to see some statistics in your syslog */ 182 /* dev_info (&port->dev, "Bytes In = %d Bytes Out = %d\n", bytes_in, bytes_out); */ 183 } 184 185 186 static int empeg_write(struct tty_struct *tty, struct usb_serial_port *port, 187 const unsigned char *buf, int count) 188 { 189 struct usb_serial *serial = port->serial; 190 struct urb *urb; 191 const unsigned char *current_position = buf; 192 unsigned long flags; 193 int status; 194 int i; 195 int bytes_sent = 0; 196 int transfer_size; 197 198 dbg("%s - port %d", __func__, port->number); 199 200 while (count > 0) { 201 /* try to find a free urb in our list of them */ 202 urb = NULL; 203 204 spin_lock_irqsave(&write_urb_pool_lock, flags); 205 206 for (i = 0; i < NUM_URBS; ++i) { 207 if (write_urb_pool[i]->status != -EINPROGRESS) { 208 urb = write_urb_pool[i]; 209 break; 210 } 211 } 212 213 spin_unlock_irqrestore(&write_urb_pool_lock, flags); 214 215 if (urb == NULL) { 216 dbg("%s - no more free urbs", __func__); 217 goto exit; 218 } 219 220 if (urb->transfer_buffer == NULL) { 221 urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC); 222 if (urb->transfer_buffer == NULL) { 223 dev_err(&port->dev, 224 "%s no more kernel memory...\n", 225 __func__); 226 goto exit; 227 } 228 } 229 230 transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE); 231 232 memcpy(urb->transfer_buffer, current_position, transfer_size); 233 234 usb_serial_debug_data(debug, &port->dev, __func__, transfer_size, urb->transfer_buffer); 235 236 /* build up our urb */ 237 usb_fill_bulk_urb( 238 urb, 239 serial->dev, 240 usb_sndbulkpipe(serial->dev, 241 port->bulk_out_endpointAddress), 242 urb->transfer_buffer, 243 transfer_size, 244 empeg_write_bulk_callback, 245 port); 246 247 /* send it down the pipe */ 248 status = usb_submit_urb(urb, GFP_ATOMIC); 249 if (status) { 250 dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __func__, status); 251 bytes_sent = status; 252 break; 253 } 254 255 current_position += transfer_size; 256 bytes_sent += transfer_size; 257 count -= transfer_size; 258 bytes_out += transfer_size; 259 260 } 261 exit: 262 return bytes_sent; 263 } 264 265 266 static int empeg_write_room(struct tty_struct *tty) 267 { 268 struct usb_serial_port *port = tty->driver_data; 269 unsigned long flags; 270 int i; 271 int room = 0; 272 273 dbg("%s - port %d", __func__, port->number); 274 275 spin_lock_irqsave(&write_urb_pool_lock, flags); 276 /* tally up the number of bytes available */ 277 for (i = 0; i < NUM_URBS; ++i) { 278 if (write_urb_pool[i]->status != -EINPROGRESS) 279 room += URB_TRANSFER_BUFFER_SIZE; 280 } 281 spin_unlock_irqrestore(&write_urb_pool_lock, flags); 282 dbg("%s - returns %d", __func__, room); 283 return room; 284 285 } 286 287 288 static int empeg_chars_in_buffer(struct tty_struct *tty) 289 { 290 struct usb_serial_port *port = tty->driver_data; 291 unsigned long flags; 292 int i; 293 int chars = 0; 294 295 dbg("%s - port %d", __func__, port->number); 296 297 spin_lock_irqsave(&write_urb_pool_lock, flags); 298 299 /* tally up the number of bytes waiting */ 300 for (i = 0; i < NUM_URBS; ++i) { 301 if (write_urb_pool[i]->status == -EINPROGRESS) 302 chars += URB_TRANSFER_BUFFER_SIZE; 303 } 304 305 spin_unlock_irqrestore(&write_urb_pool_lock, flags); 306 dbg("%s - returns %d", __func__, chars); 307 return chars; 308 } 309 310 311 static void empeg_write_bulk_callback(struct urb *urb) 312 { 313 struct usb_serial_port *port = urb->context; 314 int status = urb->status; 315 316 dbg("%s - port %d", __func__, port->number); 317 318 if (status) { 319 dbg("%s - nonzero write bulk status received: %d", 320 __func__, status); 321 return; 322 } 323 324 usb_serial_port_softint(port); 325 } 326 327 328 static void empeg_read_bulk_callback(struct urb *urb) 329 { 330 struct usb_serial_port *port = urb->context; 331 struct tty_struct *tty; 332 unsigned char *data = urb->transfer_buffer; 333 int result; 334 int status = urb->status; 335 336 dbg("%s - port %d", __func__, port->number); 337 338 if (status) { 339 dbg("%s - nonzero read bulk status received: %d", 340 __func__, status); 341 return; 342 } 343 344 usb_serial_debug_data(debug, &port->dev, __func__, 345 urb->actual_length, data); 346 tty = tty_port_tty_get(&port->port); 347 348 if (urb->actual_length) { 349 tty_insert_flip_string(tty, data, urb->actual_length); 350 tty_flip_buffer_push(tty); 351 bytes_in += urb->actual_length; 352 } 353 tty_kref_put(tty); 354 355 /* Continue trying to always read */ 356 usb_fill_bulk_urb( 357 port->read_urb, 358 port->serial->dev, 359 usb_rcvbulkpipe(port->serial->dev, 360 port->bulk_in_endpointAddress), 361 port->read_urb->transfer_buffer, 362 port->read_urb->transfer_buffer_length, 363 empeg_read_bulk_callback, 364 port); 365 366 result = usb_submit_urb(port->read_urb, GFP_ATOMIC); 367 368 if (result) 369 dev_err(&urb->dev->dev, 370 "%s - failed resubmitting read urb, error %d\n", 371 __func__, result); 372 373 return; 374 375 } 376 377 378 static void empeg_throttle(struct tty_struct *tty) 379 { 380 struct usb_serial_port *port = tty->driver_data; 381 dbg("%s - port %d", __func__, port->number); 382 usb_kill_urb(port->read_urb); 383 } 384 385 386 static void empeg_unthrottle(struct tty_struct *tty) 387 { 388 struct usb_serial_port *port = tty->driver_data; 389 int result; 390 dbg("%s - port %d", __func__, port->number); 391 392 port->read_urb->dev = port->serial->dev; 393 result = usb_submit_urb(port->read_urb, GFP_KERNEL); 394 if (result) 395 dev_err(&port->dev, 396 "%s - failed submitting read urb, error %d\n", 397 __func__, result); 398 } 399 400 401 static int empeg_startup(struct usb_serial *serial) 402 { 403 int r; 404 405 dbg("%s", __func__); 406 407 if (serial->dev->actconfig->desc.bConfigurationValue != 1) { 408 dev_err(&serial->dev->dev, "active config #%d != 1 ??\n", 409 serial->dev->actconfig->desc.bConfigurationValue); 410 return -ENODEV; 411 } 412 dbg("%s - reset config", __func__); 413 r = usb_reset_configuration(serial->dev); 414 415 /* continue on with initialization */ 416 return r; 417 418 } 419 420 421 static void empeg_init_termios(struct tty_struct *tty) 422 { 423 struct ktermios *termios = tty->termios; 424 425 /* 426 * The empeg-car player wants these particular tty settings. 427 * You could, for example, change the baud rate, however the 428 * player only supports 115200 (currently), so there is really 429 * no point in support for changes to the tty settings. 430 * (at least for now) 431 * 432 * The default requirements for this device are: 433 */ 434 termios->c_iflag 435 &= ~(IGNBRK /* disable ignore break */ 436 | BRKINT /* disable break causes interrupt */ 437 | PARMRK /* disable mark parity errors */ 438 | ISTRIP /* disable clear high bit of input characters */ 439 | INLCR /* disable translate NL to CR */ 440 | IGNCR /* disable ignore CR */ 441 | ICRNL /* disable translate CR to NL */ 442 | IXON); /* disable enable XON/XOFF flow control */ 443 444 termios->c_oflag 445 &= ~OPOST; /* disable postprocess output characters */ 446 447 termios->c_lflag 448 &= ~(ECHO /* disable echo input characters */ 449 | ECHONL /* disable echo new line */ 450 | ICANON /* disable erase, kill, werase, and rprnt special characters */ 451 | ISIG /* disable interrupt, quit, and suspend special characters */ 452 | IEXTEN); /* disable non-POSIX special characters */ 453 454 termios->c_cflag 455 &= ~(CSIZE /* no size */ 456 | PARENB /* disable parity bit */ 457 | CBAUD); /* clear current baud rate */ 458 459 termios->c_cflag 460 |= CS8; /* character size 8 bits */ 461 462 tty_encode_baud_rate(tty, 115200, 115200); 463 } 464 465 466 static int __init empeg_init(void) 467 { 468 struct urb *urb; 469 int i, retval; 470 471 /* create our write urb pool and transfer buffers */ 472 spin_lock_init(&write_urb_pool_lock); 473 for (i = 0; i < NUM_URBS; ++i) { 474 urb = usb_alloc_urb(0, GFP_KERNEL); 475 write_urb_pool[i] = urb; 476 if (urb == NULL) { 477 printk(KERN_ERR "empeg: No more urbs???\n"); 478 continue; 479 } 480 481 urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE, 482 GFP_KERNEL); 483 if (!urb->transfer_buffer) { 484 printk(KERN_ERR "empeg: %s - out of memory for urb " 485 "buffers.", __func__); 486 continue; 487 } 488 } 489 490 retval = usb_serial_register(&empeg_device); 491 if (retval) 492 goto failed_usb_serial_register; 493 retval = usb_register(&empeg_driver); 494 if (retval) 495 goto failed_usb_register; 496 497 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":" 498 DRIVER_DESC "\n"); 499 500 return 0; 501 failed_usb_register: 502 usb_serial_deregister(&empeg_device); 503 failed_usb_serial_register: 504 for (i = 0; i < NUM_URBS; ++i) { 505 if (write_urb_pool[i]) { 506 kfree(write_urb_pool[i]->transfer_buffer); 507 usb_free_urb(write_urb_pool[i]); 508 } 509 } 510 return retval; 511 } 512 513 514 static void __exit empeg_exit(void) 515 { 516 int i; 517 unsigned long flags; 518 519 usb_deregister(&empeg_driver); 520 usb_serial_deregister(&empeg_device); 521 522 spin_lock_irqsave(&write_urb_pool_lock, flags); 523 524 for (i = 0; i < NUM_URBS; ++i) { 525 if (write_urb_pool[i]) { 526 /* FIXME - uncomment the following usb_kill_urb call 527 * when the host controllers get fixed to set urb->dev 528 * = NULL after the urb is finished. Otherwise this 529 * call oopses. */ 530 /* usb_kill_urb(write_urb_pool[i]); */ 531 kfree(write_urb_pool[i]->transfer_buffer); 532 usb_free_urb(write_urb_pool[i]); 533 } 534 } 535 spin_unlock_irqrestore(&write_urb_pool_lock, flags); 536 } 537 538 539 module_init(empeg_init); 540 module_exit(empeg_exit); 541 542 MODULE_AUTHOR(DRIVER_AUTHOR); 543 MODULE_DESCRIPTION(DRIVER_DESC); 544 MODULE_LICENSE("GPL"); 545 546 module_param(debug, bool, S_IRUGO | S_IWUSR); 547 MODULE_PARM_DESC(debug, "Debug enabled or not"); 548