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 driver 15 * 16 * (07/16/2001) gb 17 * remove unused code in empeg_close() (thanks to Oliver Neukum for pointing this 18 * out) and rewrote empeg_set_termios(). 19 * 20 * (05/30/2001) gkh 21 * switched from using spinlock to a semaphore, which fixes lots of problems. 22 * 23 * (04/08/2001) gb 24 * Identify version on module load. 25 * 26 * (01/22/2001) gb 27 * Added write_room() and chars_in_buffer() support. 28 * 29 * (12/21/2000) gb 30 * Moved termio stuff inside the port->active check. 31 * Moved MOD_DEC_USE_COUNT to end of empeg_close(). 32 * 33 * (12/03/2000) gb 34 * Added port->tty->ldisc.set_termios(port->tty, NULL) to empeg_open() 35 * This notifies the tty driver that the termios have changed. 36 * 37 * (11/13/2000) gb 38 * Moved tty->low_latency = 1 from empeg_read_bulk_callback() to empeg_open() 39 * (It only needs to be set once - Doh!) 40 * 41 * (11/11/2000) gb 42 * Updated to work with id_table structure. 43 * 44 * (11/04/2000) gb 45 * Forked this from visor.c, and hacked it up to work with an 46 * Empeg ltd. empeg-car player. Constructive criticism welcomed. 47 * I would like to say, 'Thank You' to Greg Kroah-Hartman for the 48 * use of his code, and for his guidance, advice and patience. :) 49 * A 'Thank You' is in order for John Ripley of Empeg ltd for his 50 * advice, and patience too. 51 * 52 */ 53 54 #include <linux/config.h> 55 #include <linux/kernel.h> 56 #include <linux/errno.h> 57 #include <linux/init.h> 58 #include <linux/slab.h> 59 #include <linux/tty.h> 60 #include <linux/tty_driver.h> 61 #include <linux/tty_flip.h> 62 #include <linux/module.h> 63 #include <linux/spinlock.h> 64 #include <asm/uaccess.h> 65 #include <linux/usb.h> 66 #include "usb-serial.h" 67 68 static int debug; 69 70 /* 71 * Version Information 72 */ 73 #define DRIVER_VERSION "v1.2" 74 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>" 75 #define DRIVER_DESC "USB Empeg Mark I/II Driver" 76 77 #define EMPEG_VENDOR_ID 0x084f 78 #define EMPEG_PRODUCT_ID 0x0001 79 80 /* function prototypes for an empeg-car player */ 81 static int empeg_open (struct usb_serial_port *port, struct file *filp); 82 static void empeg_close (struct usb_serial_port *port, struct file *filp); 83 static int empeg_write (struct usb_serial_port *port, 84 const unsigned char *buf, 85 int count); 86 static int empeg_write_room (struct usb_serial_port *port); 87 static int empeg_chars_in_buffer (struct usb_serial_port *port); 88 static void empeg_throttle (struct usb_serial_port *port); 89 static void empeg_unthrottle (struct usb_serial_port *port); 90 static int empeg_startup (struct usb_serial *serial); 91 static void empeg_shutdown (struct usb_serial *serial); 92 static int empeg_ioctl (struct usb_serial_port *port, 93 struct file * file, 94 unsigned int cmd, 95 unsigned long arg); 96 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios); 97 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs); 98 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs); 99 100 static struct usb_device_id id_table [] = { 101 { USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) }, 102 { } /* Terminating entry */ 103 }; 104 105 MODULE_DEVICE_TABLE (usb, id_table); 106 107 static struct usb_driver empeg_driver = { 108 .owner = THIS_MODULE, 109 .name = "empeg", 110 .probe = usb_serial_probe, 111 .disconnect = usb_serial_disconnect, 112 .id_table = id_table, 113 }; 114 115 static struct usb_serial_driver empeg_device = { 116 .driver = { 117 .owner = THIS_MODULE, 118 .name = "empeg", 119 }, 120 .id_table = id_table, 121 .num_interrupt_in = 0, 122 .num_bulk_in = 1, 123 .num_bulk_out = 1, 124 .num_ports = 1, 125 .open = empeg_open, 126 .close = empeg_close, 127 .throttle = empeg_throttle, 128 .unthrottle = empeg_unthrottle, 129 .attach = empeg_startup, 130 .shutdown = empeg_shutdown, 131 .ioctl = empeg_ioctl, 132 .set_termios = empeg_set_termios, 133 .write = empeg_write, 134 .write_room = empeg_write_room, 135 .chars_in_buffer = empeg_chars_in_buffer, 136 .write_bulk_callback = empeg_write_bulk_callback, 137 .read_bulk_callback = empeg_read_bulk_callback, 138 }; 139 140 #define NUM_URBS 16 141 #define URB_TRANSFER_BUFFER_SIZE 4096 142 143 static struct urb *write_urb_pool[NUM_URBS]; 144 static spinlock_t write_urb_pool_lock; 145 static int bytes_in; 146 static int bytes_out; 147 148 /****************************************************************************** 149 * Empeg specific driver functions 150 ******************************************************************************/ 151 static int empeg_open (struct usb_serial_port *port, struct file *filp) 152 { 153 struct usb_serial *serial = port->serial; 154 int result = 0; 155 156 dbg("%s - port %d", __FUNCTION__, port->number); 157 158 /* Force default termio settings */ 159 empeg_set_termios (port, NULL) ; 160 161 bytes_in = 0; 162 bytes_out = 0; 163 164 /* Start reading from the device */ 165 usb_fill_bulk_urb( 166 port->read_urb, 167 serial->dev, 168 usb_rcvbulkpipe(serial->dev, 169 port->bulk_in_endpointAddress), 170 port->read_urb->transfer_buffer, 171 port->read_urb->transfer_buffer_length, 172 empeg_read_bulk_callback, 173 port); 174 175 result = usb_submit_urb(port->read_urb, GFP_KERNEL); 176 177 if (result) 178 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result); 179 180 return result; 181 } 182 183 184 static void empeg_close (struct usb_serial_port *port, struct file * filp) 185 { 186 dbg("%s - port %d", __FUNCTION__, port->number); 187 188 /* shutdown our bulk read */ 189 usb_kill_urb(port->read_urb); 190 /* Uncomment the following line if you want to see some statistics in your syslog */ 191 /* dev_info (&port->dev, "Bytes In = %d Bytes Out = %d\n", bytes_in, bytes_out); */ 192 } 193 194 195 static int empeg_write (struct usb_serial_port *port, const unsigned char *buf, int count) 196 { 197 struct usb_serial *serial = port->serial; 198 struct urb *urb; 199 const unsigned char *current_position = buf; 200 unsigned long flags; 201 int status; 202 int i; 203 int bytes_sent = 0; 204 int transfer_size; 205 206 dbg("%s - port %d", __FUNCTION__, port->number); 207 208 while (count > 0) { 209 210 /* try to find a free urb in our list of them */ 211 urb = NULL; 212 213 spin_lock_irqsave (&write_urb_pool_lock, flags); 214 215 for (i = 0; i < NUM_URBS; ++i) { 216 if (write_urb_pool[i]->status != -EINPROGRESS) { 217 urb = write_urb_pool[i]; 218 break; 219 } 220 } 221 222 spin_unlock_irqrestore (&write_urb_pool_lock, flags); 223 224 if (urb == NULL) { 225 dbg("%s - no more free urbs", __FUNCTION__); 226 goto exit; 227 } 228 229 if (urb->transfer_buffer == NULL) { 230 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC); 231 if (urb->transfer_buffer == NULL) { 232 dev_err(&port->dev, "%s no more kernel memory...\n", __FUNCTION__); 233 goto exit; 234 } 235 } 236 237 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE); 238 239 memcpy (urb->transfer_buffer, current_position, transfer_size); 240 241 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, urb->transfer_buffer); 242 243 /* build up our urb */ 244 usb_fill_bulk_urb ( 245 urb, 246 serial->dev, 247 usb_sndbulkpipe(serial->dev, 248 port->bulk_out_endpointAddress), 249 urb->transfer_buffer, 250 transfer_size, 251 empeg_write_bulk_callback, 252 port); 253 254 /* send it down the pipe */ 255 status = usb_submit_urb(urb, GFP_ATOMIC); 256 if (status) { 257 dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __FUNCTION__, status); 258 bytes_sent = status; 259 break; 260 } 261 262 current_position += transfer_size; 263 bytes_sent += transfer_size; 264 count -= transfer_size; 265 bytes_out += transfer_size; 266 267 } 268 269 exit: 270 return bytes_sent; 271 272 } 273 274 275 static int empeg_write_room (struct usb_serial_port *port) 276 { 277 unsigned long flags; 278 int i; 279 int room = 0; 280 281 dbg("%s - port %d", __FUNCTION__, port->number); 282 283 spin_lock_irqsave (&write_urb_pool_lock, flags); 284 285 /* tally up the number of bytes available */ 286 for (i = 0; i < NUM_URBS; ++i) { 287 if (write_urb_pool[i]->status != -EINPROGRESS) { 288 room += URB_TRANSFER_BUFFER_SIZE; 289 } 290 } 291 292 spin_unlock_irqrestore (&write_urb_pool_lock, flags); 293 294 dbg("%s - returns %d", __FUNCTION__, room); 295 296 return (room); 297 298 } 299 300 301 static int empeg_chars_in_buffer (struct usb_serial_port *port) 302 { 303 unsigned long flags; 304 int i; 305 int chars = 0; 306 307 dbg("%s - port %d", __FUNCTION__, port->number); 308 309 spin_lock_irqsave (&write_urb_pool_lock, flags); 310 311 /* tally up the number of bytes waiting */ 312 for (i = 0; i < NUM_URBS; ++i) { 313 if (write_urb_pool[i]->status == -EINPROGRESS) { 314 chars += URB_TRANSFER_BUFFER_SIZE; 315 } 316 } 317 318 spin_unlock_irqrestore (&write_urb_pool_lock, flags); 319 320 dbg("%s - returns %d", __FUNCTION__, chars); 321 322 return (chars); 323 324 } 325 326 327 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs) 328 { 329 struct usb_serial_port *port = (struct usb_serial_port *)urb->context; 330 331 dbg("%s - port %d", __FUNCTION__, port->number); 332 333 if (urb->status) { 334 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status); 335 return; 336 } 337 338 schedule_work(&port->work); 339 } 340 341 342 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs) 343 { 344 struct usb_serial_port *port = (struct usb_serial_port *)urb->context; 345 struct tty_struct *tty; 346 unsigned char *data = urb->transfer_buffer; 347 int i; 348 int result; 349 350 dbg("%s - port %d", __FUNCTION__, port->number); 351 352 if (urb->status) { 353 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status); 354 return; 355 } 356 357 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data); 358 359 tty = port->tty; 360 361 if (urb->actual_length) { 362 for (i = 0; i < urb->actual_length ; ++i) { 363 /* gb - 2000/11/13 364 * If we insert too many characters we'll overflow the buffer. 365 * This means we'll lose bytes - Decidedly bad. 366 */ 367 if(tty->flip.count >= TTY_FLIPBUF_SIZE) { 368 tty_flip_buffer_push(tty); 369 } 370 tty_insert_flip_char(tty, data[i], 0); 371 } 372 /* gb - 2000/11/13 373 * Goes straight through instead of scheduling - if tty->low_latency is set. 374 */ 375 tty_flip_buffer_push(tty); 376 bytes_in += urb->actual_length; 377 } 378 379 /* Continue trying to always read */ 380 usb_fill_bulk_urb( 381 port->read_urb, 382 port->serial->dev, 383 usb_rcvbulkpipe(port->serial->dev, 384 port->bulk_in_endpointAddress), 385 port->read_urb->transfer_buffer, 386 port->read_urb->transfer_buffer_length, 387 empeg_read_bulk_callback, 388 port); 389 390 result = usb_submit_urb(port->read_urb, GFP_ATOMIC); 391 392 if (result) 393 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result); 394 395 return; 396 397 } 398 399 400 static void empeg_throttle (struct usb_serial_port *port) 401 { 402 dbg("%s - port %d", __FUNCTION__, port->number); 403 usb_kill_urb(port->read_urb); 404 } 405 406 407 static void empeg_unthrottle (struct usb_serial_port *port) 408 { 409 int result; 410 411 dbg("%s - port %d", __FUNCTION__, port->number); 412 413 port->read_urb->dev = port->serial->dev; 414 415 result = usb_submit_urb(port->read_urb, GFP_ATOMIC); 416 417 if (result) 418 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result); 419 420 return; 421 } 422 423 424 static int empeg_startup (struct usb_serial *serial) 425 { 426 int r; 427 428 dbg("%s", __FUNCTION__); 429 430 if (serial->dev->actconfig->desc.bConfigurationValue != 1) { 431 err("active config #%d != 1 ??", 432 serial->dev->actconfig->desc.bConfigurationValue); 433 return -ENODEV; 434 } 435 dbg("%s - reset config", __FUNCTION__); 436 r = usb_reset_configuration (serial->dev); 437 438 /* continue on with initialization */ 439 return r; 440 441 } 442 443 444 static void empeg_shutdown (struct usb_serial *serial) 445 { 446 dbg ("%s", __FUNCTION__); 447 } 448 449 450 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg) 451 { 452 dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd); 453 454 return -ENOIOCTLCMD; 455 } 456 457 458 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios) 459 { 460 461 dbg("%s - port %d", __FUNCTION__, port->number); 462 463 if ((!port->tty) || (!port->tty->termios)) { 464 dbg("%s - no tty structures", __FUNCTION__); 465 return; 466 } 467 468 /* 469 * The empeg-car player wants these particular tty settings. 470 * You could, for example, change the baud rate, however the 471 * player only supports 115200 (currently), so there is really 472 * no point in support for changes to the tty settings. 473 * (at least for now) 474 * 475 * The default requirements for this device are: 476 */ 477 port->tty->termios->c_iflag 478 &= ~(IGNBRK /* disable ignore break */ 479 | BRKINT /* disable break causes interrupt */ 480 | PARMRK /* disable mark parity errors */ 481 | ISTRIP /* disable clear high bit of input characters */ 482 | INLCR /* disable translate NL to CR */ 483 | IGNCR /* disable ignore CR */ 484 | ICRNL /* disable translate CR to NL */ 485 | IXON); /* disable enable XON/XOFF flow control */ 486 487 port->tty->termios->c_oflag 488 &= ~OPOST; /* disable postprocess output characters */ 489 490 port->tty->termios->c_lflag 491 &= ~(ECHO /* disable echo input characters */ 492 | ECHONL /* disable echo new line */ 493 | ICANON /* disable erase, kill, werase, and rprnt special characters */ 494 | ISIG /* disable interrupt, quit, and suspend special characters */ 495 | IEXTEN); /* disable non-POSIX special characters */ 496 497 port->tty->termios->c_cflag 498 &= ~(CSIZE /* no size */ 499 | PARENB /* disable parity bit */ 500 | CBAUD); /* clear current baud rate */ 501 502 port->tty->termios->c_cflag 503 |= (CS8 /* character size 8 bits */ 504 | B115200); /* baud rate 115200 */ 505 506 /* 507 * Force low_latency on; otherwise the pushes are scheduled; 508 * this is bad as it opens up the possibility of dropping bytes 509 * on the floor. We don't want to drop bytes on the floor. :) 510 */ 511 port->tty->low_latency = 1; 512 513 return; 514 } 515 516 517 static int __init empeg_init (void) 518 { 519 struct urb *urb; 520 int i, retval; 521 522 /* create our write urb pool and transfer buffers */ 523 spin_lock_init (&write_urb_pool_lock); 524 for (i = 0; i < NUM_URBS; ++i) { 525 urb = usb_alloc_urb(0, GFP_KERNEL); 526 write_urb_pool[i] = urb; 527 if (urb == NULL) { 528 err("No more urbs???"); 529 continue; 530 } 531 532 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL); 533 if (!urb->transfer_buffer) { 534 err("%s - out of memory for urb buffers.", 535 __FUNCTION__); 536 continue; 537 } 538 } 539 540 retval = usb_serial_register(&empeg_device); 541 if (retval) 542 goto failed_usb_serial_register; 543 retval = usb_register(&empeg_driver); 544 if (retval) 545 goto failed_usb_register; 546 547 info(DRIVER_VERSION ":" DRIVER_DESC); 548 549 return 0; 550 failed_usb_register: 551 usb_serial_deregister(&empeg_device); 552 failed_usb_serial_register: 553 for (i = 0; i < NUM_URBS; ++i) { 554 if (write_urb_pool[i]) { 555 kfree(write_urb_pool[i]->transfer_buffer); 556 usb_free_urb(write_urb_pool[i]); 557 } 558 } 559 return retval; 560 } 561 562 563 static void __exit empeg_exit (void) 564 { 565 int i; 566 unsigned long flags; 567 568 usb_deregister(&empeg_driver); 569 usb_serial_deregister (&empeg_device); 570 571 spin_lock_irqsave (&write_urb_pool_lock, flags); 572 573 for (i = 0; i < NUM_URBS; ++i) { 574 if (write_urb_pool[i]) { 575 /* FIXME - uncomment the following usb_kill_urb call when 576 * the host controllers get fixed to set urb->dev = NULL after 577 * the urb is finished. Otherwise this call oopses. */ 578 /* usb_kill_urb(write_urb_pool[i]); */ 579 kfree(write_urb_pool[i]->transfer_buffer); 580 usb_free_urb (write_urb_pool[i]); 581 } 582 } 583 584 spin_unlock_irqrestore (&write_urb_pool_lock, flags); 585 } 586 587 588 module_init(empeg_init); 589 module_exit(empeg_exit); 590 591 MODULE_AUTHOR( DRIVER_AUTHOR ); 592 MODULE_DESCRIPTION( DRIVER_DESC ); 593 MODULE_LICENSE("GPL"); 594 595 module_param(debug, bool, S_IRUGO | S_IWUSR); 596 MODULE_PARM_DESC(debug, "Debug enabled or not"); 597