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annotate dmx_usb_module/dmx_usb.c @ 555:1b56c80b1ee4
patch for newer linux kernels which apparently have err() but not info()
Ignore-this: dc59850cb3f6d08aaa9c478aa4e4d4ef
| author | drewp@bigasterisk.com |
|---|---|
| date | Sat, 19 Jun 2010 07:02:35 +0000 |
| parents | 4e60444605f6 |
| children | 3648a427e9a0 |
| rev | line source |
|---|---|
| 355 | 1 /* |
| 2 * DMX USB driver | |
| 3 * | |
| 4 * Copyright (C) 2004,2006 Erwin Rol (erwin@erwinrol.com) | |
| 5 * | |
| 6 * This driver is based on the usb-skeleton driver; | |
| 7 * | |
| 8 * Copyright (C) 2001-2003 Greg Kroah-Hartman (greg@kroah.com) | |
| 9 * | |
| 10 * This program is free software; you can redistribute it and/or | |
| 11 * modify it under the terms of the GNU General Public License as | |
| 12 * published by the Free Software Foundation, version 2. | |
| 13 * | |
| 14 * $Id: dmx_usb.c 41 2004-09-14 23:35:25Z erwin $ | |
| 15 */ | |
| 16 | |
| 17 #include <linux/kernel.h> | |
| 18 #include <linux/errno.h> | |
| 19 #include <linux/init.h> | |
| 20 #include <linux/slab.h> | |
| 21 #include <linux/module.h> | |
| 22 #include <linux/smp_lock.h> | |
| 23 #include <linux/completion.h> | |
| 24 #include <asm/uaccess.h> | |
| 25 #include <linux/usb.h> | |
| 26 #include <linux/version.h> | |
| 27 | |
| 28 #include "dmx_usb.h" | |
| 29 | |
| 30 #ifdef CONFIG_USB_DEBUG | |
| 31 static int debug = 1; | |
| 32 #else | |
| 33 static int debug; | |
| 34 #endif | |
| 35 | |
| 36 /* Use our own dbg macro */ | |
| 37 #undef dbg | |
| 38 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG __FILE__ ": " format "\n" , ## arg); } while (0) | |
| 39 | |
| 40 | |
| 41 /* Version Information */ | |
| 42 #define DRIVER_VERSION "v0.1.20060816" | |
| 43 #define DRIVER_AUTHOR "Erwin Rol, erwin@erwinrol.com" | |
| 44 #define DRIVER_DESC "DMX USB Driver" | |
| 45 | |
| 46 /* Module parameters */ | |
| 47 #if ( LINUX_VERSION_CODE < KERNEL_VERSION(2,6,16) ) | |
| 48 MODULE_PARM(debug, "i"); | |
| 49 MODULE_PARM_DESC(debug, "Debug enabled or not"); | |
| 50 #else | |
| 51 module_param(debug, bool, S_IRUGO | S_IWUSR); | |
| 52 MODULE_PARM_DESC(debug, "Debug enabled or not"); | |
| 53 #endif | |
| 54 | |
| 55 static struct usb_device_id dmx_usb_table [] = { | |
| 56 { USB_DEVICE_VER(FTDI_VID, FTDI_8U232AM_PID, 0x400, 0xffff) }, | |
| 57 { USB_DEVICE_VER(FTDI_VID, FTDI_8U232AM_ALT_PID, 0x400, 0xffff) }, | |
| 58 { } /* Terminating entry */ | |
| 59 }; | |
| 60 | |
| 61 MODULE_DEVICE_TABLE (usb, dmx_usb_table); | |
| 62 | |
| 63 /* Get a minor range for your devices from the usb maintainer */ | |
| 64 #define DMX_USB_MINOR_BASE 192 | |
| 65 | |
| 66 /* Structure to hold all of our device specific stuff */ | |
| 67 struct dmx_usb_device { | |
| 68 struct usb_device * udev; /* save off the usb device pointer */ | |
| 69 struct usb_interface * interface; /* the interface for this device */ | |
| 70 unsigned char minor; /* the starting minor number for this device */ | |
| 71 unsigned char num_ports; /* the number of ports this device has */ | |
| 72 char num_interrupt_in; /* number of interrupt in endpoints we have */ | |
| 73 char num_bulk_in; /* number of bulk in endpoints we have */ | |
| 74 char num_bulk_out; /* number of bulk out endpoints we have */ | |
| 75 | |
| 76 unsigned char * bulk_in_buffer; /* the buffer to receive data */ | |
| 77 size_t bulk_in_size; /* the size of the receive buffer */ | |
| 78 __u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */ | |
| 79 | |
| 80 unsigned char * bulk_out_buffer; /* the buffer to send data */ | |
| 81 size_t bulk_out_size; /* the size of the send buffer */ | |
| 82 struct urb * write_urb; /* the urb used to send data */ | |
| 83 __u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */ | |
| 84 atomic_t write_busy; /* true iff write urb is busy */ | |
| 85 struct completion write_finished; /* wait for the write to finish */ | |
| 86 | |
| 87 int open; /* if the port is open or not */ | |
| 88 int present; /* if the device is not disconnected */ | |
| 89 struct semaphore sem; /* locks this structure */ | |
| 90 }; | |
| 91 | |
| 92 | |
| 93 /* prevent races between open() and disconnect() */ | |
| 94 static DECLARE_MUTEX (disconnect_sem); | |
| 95 | |
| 96 /* local function prototypes */ | |
| 97 //static ssize_t dmx_usb_read (struct file *file, char *buffer, size_t count, loff_t *ppos); | |
| 98 static ssize_t dmx_usb_write (struct file *file, const char *buffer, size_t count, loff_t *ppos); | |
| 99 static int dmx_usb_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg); | |
| 100 static int dmx_usb_open (struct inode *inode, struct file *file); | |
| 101 static int dmx_usb_release (struct inode *inode, struct file *file); | |
| 102 | |
| 103 static int dmx_usb_probe (struct usb_interface *interface, const struct usb_device_id *id); | |
| 104 static void dmx_usb_disconnect (struct usb_interface *interface); | |
| 105 | |
| 106 static void dmx_usb_write_bulk_callback (struct urb *urb, struct pt_regs *regs); | |
| 107 | |
| 108 static struct file_operations dmx_usb_fops = { | |
| 109 /* | |
| 110 * The owner field is part of the module-locking | |
| 111 * mechanism. The idea is that the kernel knows | |
| 112 * which module to increment the use-counter of | |
| 113 * BEFORE it calls the device's open() function. | |
| 114 * This also means that the kernel can decrement | |
| 115 * the use-counter again before calling release() | |
| 116 * or should the open() function fail. | |
| 117 */ | |
| 118 .owner = THIS_MODULE, | |
| 119 | |
| 120 /* .read = dmx_usb_read, */ | |
| 121 .write = dmx_usb_write, | |
| 122 .ioctl = dmx_usb_ioctl, | |
| 123 .open = dmx_usb_open, | |
| 124 .release = dmx_usb_release, | |
| 125 }; | |
| 126 | |
| 127 /* | |
| 128 * usb class driver info in order to get a minor number from the usb core, | |
| 129 * and to have the device registered with devfs and the driver core | |
| 130 */ | |
| 131 static struct usb_class_driver dmx_usb_class = { | |
| 132 .name = "usb/dmx%d", | |
| 133 .fops = &dmx_usb_fops, | |
| 134 .minor_base = DMX_USB_MINOR_BASE, | |
| 135 }; | |
| 136 | |
| 137 /* usb specific object needed to register this driver with the usb subsystem */ | |
| 138 static struct usb_driver dmx_usb_driver = { | |
| 139 #if ( LINUX_VERSION_CODE < KERNEL_VERSION(2,6,16) ) | |
| 140 .owner = THIS_MODULE, | |
| 141 #endif | |
| 142 .name = "dmx_usb", | |
| 143 .probe = dmx_usb_probe, | |
| 144 .disconnect = dmx_usb_disconnect, | |
| 145 .id_table = dmx_usb_table, | |
| 146 }; | |
| 147 | |
| 148 | |
| 149 /** | |
| 150 */ | |
| 151 static inline void dmx_usb_debug_data (const char *function, int size, const unsigned char *data) | |
| 152 { | |
| 153 int i; | |
| 154 | |
| 155 if (!debug) | |
| 156 return; | |
| 157 | |
| 158 printk (KERN_DEBUG __FILE__": %s - length = %d, data = ", | |
| 159 function, size); | |
| 160 for (i = 0; i < size; ++i) { | |
| 161 printk ("%.2x ", data[i]); | |
| 162 } | |
| 163 printk ("\n"); | |
| 164 } | |
| 165 | |
| 166 static __u32 dmx_usb_baud_to_divisor(int baud) | |
| 167 { | |
| 168 static const unsigned char divfrac[8] = { 0, 3, 2, 4, 1, 5, 6, 7 }; | |
| 169 __u32 divisor; | |
| 170 int divisor3 = 48000000 / 2 / baud; // divisor shifted 3 bits to the left | |
| 171 divisor = divisor3 >> 3; | |
| 172 divisor |= (__u32)divfrac[divisor3 & 0x7] << 14; | |
| 173 /* Deal with special cases for highest baud rates. */ | |
| 174 if (divisor == 1) divisor = 0; else // 1.0 | |
| 175 if (divisor == 0x4001) divisor = 1; // 1.5 | |
| 176 return divisor; | |
| 177 } | |
| 178 | |
| 179 static int dmx_usb_set_speed(struct dmx_usb_device* dev) | |
| 180 { | |
| 181 char *buf; | |
| 182 __u16 urb_value; | |
| 183 __u16 urb_index; | |
| 184 __u32 urb_index_value; | |
| 185 int rv; | |
| 186 | |
| 187 buf = kmalloc(1, GFP_NOIO); | |
| 188 if (!buf) | |
| 189 return -ENOMEM; | |
| 190 | |
| 191 urb_index_value = dmx_usb_baud_to_divisor(250000); | |
| 192 urb_value = (__u16)urb_index_value; | |
| 193 urb_index = (__u16)(urb_index_value >> 16); | |
| 194 | |
| 195 rv = usb_control_msg(dev->udev, | |
| 196 usb_sndctrlpipe(dev->udev, 0), | |
| 197 FTDI_SIO_SET_BAUDRATE_REQUEST, | |
| 198 FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE, | |
| 199 urb_value, urb_index, | |
| 200 buf, 0, HZ*10); | |
| 201 | |
| 202 kfree(buf); | |
| 203 return rv; | |
| 204 } | |
| 205 | |
| 206 static int dmx_usb_setup(struct dmx_usb_device* dev) | |
| 207 { | |
| 208 __u16 urb_value; | |
| 209 char buf[1]; | |
| 210 | |
| 211 urb_value = FTDI_SIO_SET_DATA_STOP_BITS_2 | FTDI_SIO_SET_DATA_PARITY_NONE; | |
| 212 urb_value |= 8; // number of data bits | |
| 213 | |
| 214 if (usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), | |
| 215 FTDI_SIO_SET_DATA_REQUEST, | |
| 216 FTDI_SIO_SET_DATA_REQUEST_TYPE, | |
| 217 urb_value , 0, | |
| 218 buf, 0, HZ*10) < 0) { | |
| 219 err("%s FAILED to set databits/stopbits/parity", __FUNCTION__); | |
| 220 } | |
| 221 | |
| 222 if (usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), | |
| 223 FTDI_SIO_SET_FLOW_CTRL_REQUEST, | |
| 224 FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE, | |
| 225 0, 0, | |
| 226 buf, 0, HZ*10) < 0) { | |
| 227 err("%s error from disable flowcontrol urb", __FUNCTION__); | |
| 228 } | |
| 229 | |
| 230 dmx_usb_set_speed(dev); | |
| 231 | |
| 232 return 0; | |
| 233 } | |
| 234 | |
| 235 static void dmx_usb_set_break(struct dmx_usb_device* dev, int break_state) | |
| 236 { | |
| 237 __u16 urb_value = FTDI_SIO_SET_DATA_STOP_BITS_2 | FTDI_SIO_SET_DATA_PARITY_NONE | 8; | |
| 238 | |
| 239 char buf[2]; | |
| 240 | |
| 241 if (break_state) { | |
| 242 urb_value |= FTDI_SIO_SET_BREAK; | |
| 243 } | |
| 244 | |
| 245 if (usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), | |
| 246 FTDI_SIO_SET_DATA_REQUEST, | |
| 247 FTDI_SIO_SET_DATA_REQUEST_TYPE, | |
| 248 urb_value , 0, | |
| 249 buf, 2, HZ*10) < 0) { | |
| 250 err("%s FAILED to enable/disable break state (state was %d)", __FUNCTION__,break_state); | |
| 251 } | |
| 252 | |
| 253 | |
| 254 dbg("%s break state is %d - urb is %d", __FUNCTION__,break_state, urb_value); | |
| 255 } | |
| 256 | |
| 257 /** | |
| 258 */ | |
| 259 static inline void dmx_usb_delete (struct dmx_usb_device *dev) | |
| 260 { | |
| 261 kfree (dev->bulk_in_buffer); | |
| 262 usb_buffer_free (dev->udev, dev->bulk_out_size, | |
| 263 dev->bulk_out_buffer, | |
| 264 dev->write_urb->transfer_dma); | |
| 265 usb_free_urb (dev->write_urb); | |
| 266 kfree (dev); | |
| 267 } | |
| 268 | |
| 269 | |
| 270 /** | |
| 271 */ | |
| 272 static int dmx_usb_open (struct inode *inode, struct file *file) | |
| 273 { | |
| 274 struct dmx_usb_device *dev = NULL; | |
| 275 struct usb_interface *interface; | |
| 276 int subminor; | |
| 277 int retval = 0; | |
| 278 | |
| 279 dbg("%s", __FUNCTION__); | |
| 280 | |
| 281 subminor = iminor(inode); | |
| 282 | |
| 283 /* prevent disconnects */ | |
| 284 down (&disconnect_sem); | |
| 285 | |
| 286 interface = usb_find_interface (&dmx_usb_driver, subminor); | |
| 287 if (!interface) { | |
| 288 err ("%s - error, can't find device for minor %d", | |
| 289 __FUNCTION__, subminor); | |
| 290 retval = -ENODEV; | |
| 291 goto exit_no_device; | |
| 292 } | |
| 293 | |
| 294 dev = usb_get_intfdata(interface); | |
| 295 if (!dev) { | |
| 296 retval = -ENODEV; | |
| 297 goto exit_no_device; | |
| 298 } | |
| 299 | |
| 300 /* lock this device */ | |
| 301 down (&dev->sem); | |
| 302 | |
| 303 /* increment our usage count for the driver */ | |
| 304 ++dev->open; | |
| 305 | |
| 306 /* save our object in the file's private structure */ | |
| 307 file->private_data = dev; | |
| 308 | |
| 309 /* unlock this device */ | |
| 310 up (&dev->sem); | |
| 311 | |
| 312 exit_no_device: | |
| 313 up (&disconnect_sem); | |
| 314 return retval; | |
| 315 } | |
| 316 | |
| 317 | |
| 318 /** | |
| 319 */ | |
| 320 static int dmx_usb_release (struct inode *inode, struct file *file) | |
| 321 { | |
| 322 struct dmx_usb_device *dev; | |
| 323 int retval = 0; | |
| 324 | |
| 325 dev = (struct dmx_usb_device *)file->private_data; | |
| 326 if (dev == NULL) { | |
| 327 dbg ("%s - object is NULL", __FUNCTION__); | |
| 328 return -ENODEV; | |
| 329 } | |
| 330 | |
| 331 dbg("%s - minor %d", __FUNCTION__, dev->minor); | |
| 332 | |
| 333 /* lock our device */ | |
| 334 down (&dev->sem); | |
| 335 | |
| 336 if (dev->open <= 0) { | |
| 337 dbg ("%s - device not opened", __FUNCTION__); | |
| 338 retval = -ENODEV; | |
| 339 goto exit_not_opened; | |
| 340 } | |
| 341 | |
| 342 /* wait for any bulk writes that might be going on to finish up */ | |
| 343 if (atomic_read (&dev->write_busy)) | |
| 344 wait_for_completion (&dev->write_finished); | |
| 345 | |
| 346 --dev->open; | |
| 347 | |
| 348 if (!dev->present && !dev->open) { | |
| 349 /* the device was unplugged before the file was released */ | |
| 350 up (&dev->sem); | |
| 351 dmx_usb_delete (dev); | |
| 352 return 0; | |
| 353 } | |
| 354 | |
| 355 exit_not_opened: | |
| 356 up (&dev->sem); | |
| 357 | |
| 358 return retval; | |
| 359 } | |
| 360 | |
| 361 #if 0 | |
| 362 | |
| 363 Read is not yet supported | |
| 364 | |
| 365 /** | |
| 366 */ | |
| 367 static ssize_t dmx_usb_read (struct file *file, char *buffer, size_t count, loff_t *ppos) | |
| 368 { | |
| 369 struct dmx_usb_device *dev; | |
| 370 int retval = 0; | |
| 371 int bytes_read; | |
| 372 | |
| 373 dev = (struct dmx_usb_device *)file->private_data; | |
| 374 | |
| 375 dbg("%s - minor %d, count = %Zd", __FUNCTION__, dev->minor, count); | |
| 376 | |
| 377 /* lock this object */ | |
| 378 down (&dev->sem); | |
| 379 | |
| 380 /* verify that the device wasn't unplugged */ | |
| 381 if (!dev->present) { | |
| 382 up (&dev->sem); | |
| 383 return -ENODEV; | |
| 384 } | |
| 385 | |
| 386 /* do a blocking bulk read to get data from the device */ | |
| 387 retval = usb_bulk_msg (dev->udev, | |
| 388 usb_rcvbulkpipe (dev->udev, | |
| 389 dev->bulk_in_endpointAddr), | |
| 390 dev->bulk_in_buffer, | |
| 391 min (dev->bulk_in_size, count), | |
| 392 &bytes_read, HZ*10); | |
| 393 | |
| 394 /* if the read was successful, copy the data to userspace */ | |
| 395 if (!retval) { | |
| 396 if (copy_to_user (buffer, dev->bulk_in_buffer+2, bytes_read-2)) | |
| 397 retval = -EFAULT; | |
| 398 else | |
| 399 retval = bytes_read; | |
| 400 } | |
| 401 | |
| 402 /* unlock the device */ | |
| 403 up (&dev->sem); | |
| 404 return retval; | |
| 405 } | |
| 406 | |
| 407 #endif | |
| 408 | |
| 409 static __u16 dmx_usb_get_status(struct dmx_usb_device* dev) | |
| 410 { | |
| 411 int retval = 0; | |
| 412 int count = 0; | |
| 413 __u16 buf; | |
| 414 | |
| 415 retval = usb_bulk_msg (dev->udev, | |
| 416 usb_rcvbulkpipe (dev->udev, dev->bulk_in_endpointAddr), | |
| 417 &buf, 2, &count, HZ*10); | |
| 418 | |
| 419 if (retval) | |
| 420 return 0; | |
| 421 | |
| 422 return buf; | |
| 423 } | |
| 424 | |
| 425 | |
| 426 | |
| 427 /** | |
| 428 * dmx_usb_write | |
| 429 * | |
| 430 * A device driver has to decide how to report I/O errors back to the | |
| 431 * user. The safest course is to wait for the transfer to finish before | |
| 432 * returning so that any errors will be reported reliably. dmx_usb_read() | |
| 433 * works like this. But waiting for I/O is slow, so many drivers only | |
| 434 * check for errors during I/O initiation and do not report problems | |
| 435 * that occur during the actual transfer. That's what we will do here. | |
| 436 * | |
| 437 * A driver concerned with maximum I/O throughput would use double- | |
| 438 * buffering: Two urbs would be devoted to write transfers, so that | |
| 439 * one urb could always be active while the other was waiting for the | |
| 440 * user to send more data. | |
| 441 */ | |
| 442 static ssize_t dmx_usb_write (struct file *file, const char *buffer, size_t count, loff_t *ppos) | |
| 443 { | |
| 444 struct dmx_usb_device *dev; | |
| 445 ssize_t bytes_written = 0; | |
| 446 int retval = 0; | |
| 447 __u16 stat; | |
| 448 | |
| 449 dev = (struct dmx_usb_device *)file->private_data; | |
| 450 | |
| 451 dbg("%s - minor %d, count = %Zd", __FUNCTION__, dev->minor, count); | |
| 452 | |
| 453 /* lock this object */ | |
| 454 down (&dev->sem); | |
| 455 | |
| 456 /* verify that the device wasn't unplugged */ | |
| 457 if (!dev->present) { | |
| 458 retval = -ENODEV; | |
| 459 goto exit; | |
| 460 } | |
| 461 | |
| 462 /* verify that we actually have some data to write */ | |
| 463 if (count == 0) { | |
| 464 dbg("%s - write request of 0 bytes", __FUNCTION__); | |
| 465 goto exit; | |
| 466 } | |
| 467 | |
| 468 /* wait for a previous write to finish up; we don't use a timeout | |
| 469 * and so a nonresponsive device can delay us indefinitely. | |
| 470 */ | |
| 471 if (atomic_read (&dev->write_busy)) | |
| 472 wait_for_completion (&dev->write_finished); | |
| 473 | |
| 474 /* we can only write as much as our buffer will hold */ | |
| 475 bytes_written = min (dev->bulk_out_size, count); | |
| 476 | |
| 477 /* copy the data from userspace into our transfer buffer; | |
| 478 * this is the only copy required. | |
| 479 */ | |
| 480 if (copy_from_user(dev->write_urb->transfer_buffer, buffer, | |
| 481 bytes_written)) { | |
| 482 retval = -EFAULT; | |
| 483 goto exit; | |
| 484 } | |
| 485 | |
| 486 dmx_usb_debug_data (__FUNCTION__, bytes_written, | |
| 487 dev->write_urb->transfer_buffer); | |
| 488 | |
| 489 /* this urb was already set up, except for this write size */ | |
| 490 dev->write_urb->transfer_buffer_length = bytes_written; | |
| 491 | |
| 492 /* Poll the device to see if the transmit buffer is empty */ | |
| 493 do { | |
| 494 stat = dmx_usb_get_status(dev); | |
| 495 if (stat == 0) { | |
| 496 retval = -EFAULT; | |
| 497 goto exit; | |
| 498 } | |
| 499 } while ( (stat & ((FTDI_RS_TEMT) << 8) ) == 0 ) ; | |
| 500 | |
| 501 /* the transmit buffer is empty, now toggle the break */ | |
| 502 dmx_usb_set_break(dev, 1); | |
| 503 dmx_usb_set_break(dev, 0); | |
| 504 | |
| 505 /* send the data out the bulk port */ | |
| 506 /* a character device write uses GFP_KERNEL, | |
| 507 unless a spinlock is held */ | |
| 508 init_completion (&dev->write_finished); | |
| 509 atomic_set (&dev->write_busy, 1); | |
| 510 retval = usb_submit_urb(dev->write_urb, GFP_KERNEL); | |
| 511 if (retval) { | |
| 512 atomic_set (&dev->write_busy, 0); | |
| 513 err("%s - failed submitting write urb, error %d", | |
| 514 __FUNCTION__, retval); | |
| 515 } else { | |
| 516 retval = bytes_written; | |
| 517 } | |
| 518 | |
| 519 exit: | |
| 520 /* unlock the device */ | |
| 521 up (&dev->sem); | |
| 522 | |
| 523 return retval; | |
| 524 } | |
| 525 | |
| 526 | |
| 527 /** | |
| 528 */ | |
| 529 static int dmx_usb_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) | |
| 530 { | |
| 531 struct dmx_usb_device *dev; | |
| 532 | |
| 533 dev = (struct dmx_usb_device *)file->private_data; | |
| 534 | |
| 535 /* lock this object */ | |
| 536 down (&dev->sem); | |
| 537 | |
| 538 /* verify that the device wasn't unplugged */ | |
| 539 if (!dev->present) { | |
| 540 up (&dev->sem); | |
| 541 return -ENODEV; | |
| 542 } | |
| 543 | |
| 544 dbg("%s - minor %d, cmd 0x%.4x, arg %ld", __FUNCTION__, | |
| 545 dev->minor, cmd, arg); | |
| 546 | |
| 547 /* fill in your device specific stuff here */ | |
| 548 | |
| 549 /* unlock the device */ | |
| 550 up (&dev->sem); | |
| 551 | |
| 552 /* return that we did not understand this ioctl call */ | |
| 553 return -ENOTTY; | |
| 554 } | |
| 555 | |
| 556 | |
| 557 /** | |
| 558 */ | |
| 559 static void dmx_usb_write_bulk_callback (struct urb *urb, struct pt_regs *regs) | |
| 560 { | |
| 561 struct dmx_usb_device *dev = (struct dmx_usb_device *)urb->context; | |
| 562 | |
| 563 dbg("%s - minor %d", __FUNCTION__, dev->minor); | |
| 564 | |
| 565 /* sync/async unlink faults aren't errors */ | |
| 566 if (urb->status && !(urb->status == -ENOENT || | |
| 567 urb->status == -ECONNRESET)) { | |
| 568 dbg("%s - nonzero write bulk status received: %d", | |
| 569 __FUNCTION__, urb->status); | |
| 570 } | |
| 571 | |
| 572 /* notify anyone waiting that the write has finished */ | |
| 573 atomic_set (&dev->write_busy, 0); | |
| 574 complete (&dev->write_finished); | |
| 575 } | |
| 576 | |
| 577 /** | |
| 578 * | |
| 579 * Called by the usb core when a new device is connected that it thinks | |
| 580 * this driver might be interested in. | |
| 581 */ | |
| 582 static int dmx_usb_probe(struct usb_interface *interface, const struct usb_device_id *id) | |
| 583 { | |
| 584 struct usb_device *udev = interface_to_usbdev(interface); | |
| 585 struct dmx_usb_device *dev = NULL; | |
| 586 struct usb_host_interface *iface_desc; | |
| 587 struct usb_endpoint_descriptor *endpoint; | |
| 588 size_t buffer_size; | |
| 589 int i; | |
| 590 int retval = -ENOMEM; | |
| 591 | |
| 592 /* See if the device offered us matches what we can accept */ | |
| 593 if ((udev->descriptor.idVendor != FTDI_VID) || | |
| 594 (udev->descriptor.idProduct != FTDI_8U232AM_PID)) { | |
| 595 return -ENODEV; | |
| 596 } | |
| 597 | |
| 598 /* allocate memory for our device state and initialize it */ | |
| 599 dev = kmalloc (sizeof(struct dmx_usb_device), GFP_KERNEL); | |
| 600 if (dev == NULL) { | |
| 601 err ("Out of memory"); | |
| 602 return -ENOMEM; | |
| 603 } | |
| 604 memset (dev, 0x00, sizeof (*dev)); | |
| 605 | |
| 606 init_MUTEX (&dev->sem); | |
| 607 dev->udev = udev; | |
| 608 dev->interface = interface; | |
| 609 | |
| 610 /* set up the endpoint information */ | |
| 611 /* check out the endpoints */ | |
| 612 /* use only the first bulk-in and bulk-out endpoints */ | |
| 613 iface_desc = &interface->altsetting[0]; | |
| 614 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { | |
| 615 endpoint = &iface_desc->endpoint[i].desc; | |
| 616 | |
| 617 if (!dev->bulk_in_endpointAddr && | |
| 618 (endpoint->bEndpointAddress & USB_DIR_IN) && | |
| 619 ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) | |
| 620 == USB_ENDPOINT_XFER_BULK)) { | |
| 621 /* we found a bulk in endpoint */ | |
| 622 buffer_size = endpoint->wMaxPacketSize; | |
| 623 dev->bulk_in_size = buffer_size; | |
| 624 dev->bulk_in_endpointAddr = endpoint->bEndpointAddress; | |
| 625 dev->bulk_in_buffer = kmalloc (buffer_size, GFP_KERNEL); | |
| 626 if (!dev->bulk_in_buffer) { | |
| 627 err("Couldn't allocate bulk_in_buffer"); | |
| 628 goto error; | |
| 629 } | |
| 630 } | |
| 631 | |
| 632 if (!dev->bulk_out_endpointAddr && | |
| 633 !(endpoint->bEndpointAddress & USB_DIR_IN) && | |
| 634 ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) | |
| 635 == USB_ENDPOINT_XFER_BULK)) { | |
| 636 /* we found a bulk out endpoint */ | |
| 637 /* a probe() may sleep and has no restrictions on memory allocations */ | |
| 638 dev->write_urb = usb_alloc_urb(0, GFP_KERNEL); | |
| 639 if (!dev->write_urb) { | |
| 640 err("No free urbs available"); | |
| 641 goto error; | |
| 642 } | |
| 643 dev->bulk_out_endpointAddr = endpoint->bEndpointAddress; | |
| 644 | |
| 645 /* on some platforms using this kind of buffer alloc | |
| 646 * call eliminates a dma "bounce buffer". | |
| 647 * | |
| 648 * NOTE: you'd normally want i/o buffers that hold | |
| 649 * more than one packet, so that i/o delays between | |
| 650 * packets don't hurt throughput. | |
| 651 */ | |
| 652 buffer_size = endpoint->wMaxPacketSize; | |
| 653 dev->bulk_out_size = 513; | |
| 654 dev->write_urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; | |
| 655 dev->bulk_out_buffer = usb_buffer_alloc (udev, | |
| 656 buffer_size, GFP_KERNEL, | |
| 657 &dev->write_urb->transfer_dma); | |
| 658 if (!dev->bulk_out_buffer) { | |
| 659 err("Couldn't allocate bulk_out_buffer"); | |
| 660 goto error; | |
| 661 } | |
| 662 usb_fill_bulk_urb(dev->write_urb, udev, | |
| 663 usb_sndbulkpipe(udev, | |
| 664 endpoint->bEndpointAddress), | |
| 665 dev->bulk_out_buffer, buffer_size, | |
| 666 dmx_usb_write_bulk_callback, dev); | |
| 667 } | |
| 668 } | |
| 669 if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) { | |
| 670 err("Couldn't find both bulk-in and bulk-out endpoints"); | |
| 671 goto error; | |
| 672 } | |
| 673 | |
| 674 dmx_usb_setup(dev); | |
| 675 | |
| 676 /* allow device read, write and ioctl */ | |
| 677 dev->present = 1; | |
| 678 | |
| 679 /* we can register the device now, as it is ready */ | |
| 680 usb_set_intfdata (interface, dev); | |
| 681 retval = usb_register_dev (interface, &dmx_usb_class); | |
| 682 if (retval) { | |
| 683 /* something prevented us from registering this driver */ | |
| 684 err ("Not able to get a minor for this device."); | |
| 685 usb_set_intfdata (interface, NULL); | |
| 686 goto error; | |
| 687 } | |
| 688 | |
| 689 dev->minor = interface->minor; | |
| 690 | |
| 691 /* let the user know what node this device is now attached to */ | |
|
555
1b56c80b1ee4
patch for newer linux kernels which apparently have err() but not info()
drewp@bigasterisk.com
parents:
355
diff
changeset
|
692 err ("info: DMX USB device now attached to dmx%d", dev->minor); |
| 355 | 693 return 0; |
| 694 | |
| 695 error: | |
| 696 dmx_usb_delete (dev); | |
| 697 return retval; | |
| 698 } | |
| 699 | |
| 700 | |
| 701 /** | |
| 702 * | |
| 703 * Called by the usb core when the device is removed from the system. | |
| 704 * | |
| 705 * This routine guarantees that the driver will not submit any more urbs | |
| 706 * by clearing dev->udev. It is also supposed to terminate any currently | |
| 707 * active urbs. Unfortunately, usb_bulk_msg(), used in dmx_usb_read(), does | |
| 708 * not provide any way to do this. But at least we can cancel an active | |
| 709 * write. | |
| 710 */ | |
| 711 static void dmx_usb_disconnect(struct usb_interface *interface) | |
| 712 { | |
| 713 struct dmx_usb_device *dev; | |
| 714 int minor; | |
| 715 | |
| 716 /* prevent races with open() */ | |
| 717 down (&disconnect_sem); | |
| 718 | |
| 719 dev = usb_get_intfdata (interface); | |
| 720 usb_set_intfdata (interface, NULL); | |
| 721 | |
| 722 down (&dev->sem); | |
| 723 | |
| 724 minor = dev->minor; | |
| 725 | |
| 726 /* give back our minor */ | |
| 727 usb_deregister_dev (interface, &dmx_usb_class); | |
| 728 | |
| 729 /* terminate an ongoing write */ | |
| 730 if (atomic_read (&dev->write_busy)) { | |
| 731 usb_unlink_urb (dev->write_urb); | |
| 732 wait_for_completion (&dev->write_finished); | |
| 733 } | |
| 734 | |
| 735 /* prevent device read, write and ioctl */ | |
| 736 dev->present = 0; | |
| 737 | |
| 738 up (&dev->sem); | |
| 739 | |
| 740 /* if the device is opened, dmx_usb_release will clean this up */ | |
| 741 if (!dev->open) | |
| 742 dmx_usb_delete (dev); | |
| 743 | |
| 744 up (&disconnect_sem); | |
| 745 | |
|
555
1b56c80b1ee4
patch for newer linux kernels which apparently have err() but not info()
drewp@bigasterisk.com
parents:
355
diff
changeset
|
746 err("info: DMX USB #%d now disconnected", minor); |
| 355 | 747 } |
| 748 | |
| 749 | |
| 750 | |
| 751 /** | |
| 752 * dmx_usb_init | |
| 753 */ | |
| 754 static int __init dmx_usb_init(void) | |
| 755 { | |
| 756 int result; | |
| 757 | |
| 758 /* register this driver with the USB subsystem */ | |
| 759 result = usb_register(&dmx_usb_driver); | |
| 760 if (result) { | |
| 761 err("usb_register failed. Error number %d", | |
| 762 result); | |
| 763 return result; | |
| 764 } | |
| 765 | |
|
555
1b56c80b1ee4
patch for newer linux kernels which apparently have err() but not info()
drewp@bigasterisk.com
parents:
355
diff
changeset
|
766 err("info: " DRIVER_DESC " " DRIVER_VERSION); |
| 355 | 767 return 0; |
| 768 } | |
| 769 | |
| 770 | |
| 771 /** | |
| 772 * dmx_usb_exit | |
| 773 */ | |
| 774 static void __exit dmx_usb_exit(void) | |
| 775 { | |
| 776 /* deregister this driver with the USB subsystem */ | |
| 777 usb_deregister(&dmx_usb_driver); | |
| 778 } | |
| 779 | |
| 780 | |
| 781 module_init (dmx_usb_init); | |
| 782 module_exit (dmx_usb_exit); | |
| 783 | |
| 784 MODULE_AUTHOR(DRIVER_AUTHOR); | |
| 785 MODULE_DESCRIPTION(DRIVER_DESC); | |
| 786 MODULE_LICENSE("GPL"); | |
| 787 |