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sq905.c
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1 /*
2  * SQ905 subdriver
3  *
4  * Copyright (C) 2008, 2009 Adam Baker and Theodore Kilgore
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  */
20 
21 /*
22  * History and Acknowledgments
23  *
24  * The original Linux driver for SQ905 based cameras was written by
25  * Marcell Lengyel and furter developed by many other contributors
26  * and is available from http://sourceforge.net/projects/sqcam/
27  *
28  * This driver takes advantage of the reverse engineering work done for
29  * that driver and for libgphoto2 but shares no code with them.
30  *
31  * This driver has used as a base the finepix driver and other gspca
32  * based drivers and may still contain code fragments taken from those
33  * drivers.
34  */
35 
36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
37 
38 #define MODULE_NAME "sq905"
39 
40 #include <linux/workqueue.h>
41 #include <linux/slab.h>
42 #include "gspca.h"
43 
44 MODULE_AUTHOR("Adam Baker <[email protected]>, "
45  "Theodore Kilgore <[email protected]>");
46 MODULE_DESCRIPTION("GSPCA/SQ905 USB Camera Driver");
47 MODULE_LICENSE("GPL");
48 
49 /* Default timeouts, in ms */
50 #define SQ905_CMD_TIMEOUT 500
51 #define SQ905_DATA_TIMEOUT 1000
52 
53 /* Maximum transfer size to use. */
54 #define SQ905_MAX_TRANSFER 0x8000
55 #define FRAME_HEADER_LEN 64
56 
57 /* The known modes, or registers. These go in the "value" slot. */
58 
59 /* 00 is "none" obviously */
60 
61 #define SQ905_BULK_READ 0x03 /* precedes any bulk read */
62 #define SQ905_COMMAND 0x06 /* precedes the command codes below */
63 #define SQ905_PING 0x07 /* when reading an "idling" command */
64 #define SQ905_READ_DONE 0xc0 /* ack bulk read completed */
65 
66 /* Any non-zero value in the bottom 2 bits of the 2nd byte of
67  * the ID appears to indicate the camera can do 640*480. If the
68  * LSB of that byte is set the image is just upside down, otherwise
69  * it is rotated 180 degrees. */
70 #define SQ905_HIRES_MASK 0x00000300
71 #define SQ905_ORIENTATION_MASK 0x00000100
72 
73 /* Some command codes. These go in the "index" slot. */
74 
75 #define SQ905_ID 0xf0 /* asks for model string */
76 #define SQ905_CONFIG 0x20 /* gets photo alloc. table, not used here */
77 #define SQ905_DATA 0x30 /* accesses photo data, not used here */
78 #define SQ905_CLEAR 0xa0 /* clear everything */
79 #define SQ905_CAPTURE_LOW 0x60 /* Starts capture at 160x120 */
80 #define SQ905_CAPTURE_MED 0x61 /* Starts capture at 320x240 */
81 #define SQ905_CAPTURE_HIGH 0x62 /* Starts capture at 640x480 (some cams only) */
82 /* note that the capture command also controls the output dimensions */
83 
84 /* Structure to hold all of our device specific stuff */
85 struct sd {
86  struct gspca_dev gspca_dev; /* !! must be the first item */
87 
88  /*
89  * Driver stuff
90  */
91  struct work_struct work_struct;
93 };
94 
95 static struct v4l2_pix_format sq905_mode[] = {
97  .bytesperline = 160,
98  .sizeimage = 160 * 120,
99  .colorspace = V4L2_COLORSPACE_SRGB,
100  .priv = 0},
102  .bytesperline = 320,
103  .sizeimage = 320 * 240,
104  .colorspace = V4L2_COLORSPACE_SRGB,
105  .priv = 0},
107  .bytesperline = 640,
108  .sizeimage = 640 * 480,
109  .colorspace = V4L2_COLORSPACE_SRGB,
110  .priv = 0}
111 };
112 
113 /*
114  * Send a command to the camera.
115  */
116 static int sq905_command(struct gspca_dev *gspca_dev, u16 index)
117 {
118  int ret;
119 
120  gspca_dev->usb_buf[0] = '\0';
121  ret = usb_control_msg(gspca_dev->dev,
122  usb_sndctrlpipe(gspca_dev->dev, 0),
123  USB_REQ_SYNCH_FRAME, /* request */
125  SQ905_COMMAND, index, gspca_dev->usb_buf, 1,
127  if (ret < 0) {
128  pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
129  return ret;
130  }
131 
132  ret = usb_control_msg(gspca_dev->dev,
133  usb_sndctrlpipe(gspca_dev->dev, 0),
134  USB_REQ_SYNCH_FRAME, /* request */
136  SQ905_PING, 0, gspca_dev->usb_buf, 1,
138  if (ret < 0) {
139  pr_err("%s: usb_control_msg failed 2 (%d)\n", __func__, ret);
140  return ret;
141  }
142 
143  return 0;
144 }
145 
146 /*
147  * Acknowledge the end of a frame - see warning on sq905_command.
148  */
149 static int sq905_ack_frame(struct gspca_dev *gspca_dev)
150 {
151  int ret;
152 
153  gspca_dev->usb_buf[0] = '\0';
154  ret = usb_control_msg(gspca_dev->dev,
155  usb_sndctrlpipe(gspca_dev->dev, 0),
156  USB_REQ_SYNCH_FRAME, /* request */
158  SQ905_READ_DONE, 0, gspca_dev->usb_buf, 1,
160  if (ret < 0) {
161  pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
162  return ret;
163  }
164 
165  return 0;
166 }
167 
168 /*
169  * request and read a block of data - see warning on sq905_command.
170  */
171 static int
172 sq905_read_data(struct gspca_dev *gspca_dev, u8 *data, int size, int need_lock)
173 {
174  int ret;
175  int act_len;
176 
177  gspca_dev->usb_buf[0] = '\0';
178  if (need_lock)
179  mutex_lock(&gspca_dev->usb_lock);
180  ret = usb_control_msg(gspca_dev->dev,
181  usb_sndctrlpipe(gspca_dev->dev, 0),
182  USB_REQ_SYNCH_FRAME, /* request */
184  SQ905_BULK_READ, size, gspca_dev->usb_buf,
185  1, SQ905_CMD_TIMEOUT);
186  if (need_lock)
187  mutex_unlock(&gspca_dev->usb_lock);
188  if (ret < 0) {
189  pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
190  return ret;
191  }
192  ret = usb_bulk_msg(gspca_dev->dev,
193  usb_rcvbulkpipe(gspca_dev->dev, 0x81),
194  data, size, &act_len, SQ905_DATA_TIMEOUT);
195 
196  /* successful, it returns 0, otherwise negative */
197  if (ret < 0 || act_len != size) {
198  pr_err("bulk read fail (%d) len %d/%d\n", ret, act_len, size);
199  return -EIO;
200  }
201  return 0;
202 }
203 
204 /*
205  * This function is called as a workqueue function and runs whenever the camera
206  * is streaming data. Because it is a workqueue function it is allowed to sleep
207  * so we can use synchronous USB calls. To avoid possible collisions with other
208  * threads attempting to use gspca_dev->usb_buf we take the usb_lock when
209  * performing USB operations using it. In practice we don't really need this
210  * as the camera doesn't provide any controls.
211  */
212 static void sq905_dostream(struct work_struct *work)
213 {
214  struct sd *dev = container_of(work, struct sd, work_struct);
215  struct gspca_dev *gspca_dev = &dev->gspca_dev;
216  int bytes_left; /* bytes remaining in current frame. */
217  int data_len; /* size to use for the next read. */
218  int header_read; /* true if we have already read the frame header. */
219  int packet_type;
220  int frame_sz;
221  int ret;
222  u8 *data;
223  u8 *buffer;
224 
226  if (!buffer) {
227  pr_err("Couldn't allocate USB buffer\n");
228  goto quit_stream;
229  }
230 
231  frame_sz = gspca_dev->cam.cam_mode[gspca_dev->curr_mode].sizeimage
233 
234  while (gspca_dev->present && gspca_dev->streaming) {
235 #ifdef CONFIG_PM
236  if (gspca_dev->frozen)
237  break;
238 #endif
239  /* request some data and then read it until we have
240  * a complete frame. */
241  bytes_left = frame_sz;
242  header_read = 0;
243 
244  /* Note we do not check for gspca_dev->streaming here, as
245  we must finish reading an entire frame, otherwise the
246  next time we stream we start reading in the middle of a
247  frame. */
248  while (bytes_left > 0 && gspca_dev->present) {
249  data_len = bytes_left > SQ905_MAX_TRANSFER ?
250  SQ905_MAX_TRANSFER : bytes_left;
251  ret = sq905_read_data(gspca_dev, buffer, data_len, 1);
252  if (ret < 0)
253  goto quit_stream;
254  PDEBUG(D_PACK,
255  "Got %d bytes out of %d for frame",
256  data_len, bytes_left);
257  bytes_left -= data_len;
258  data = buffer;
259  if (!header_read) {
260  packet_type = FIRST_PACKET;
261  /* The first 64 bytes of each frame are
262  * a header full of FF 00 bytes */
263  data += FRAME_HEADER_LEN;
264  data_len -= FRAME_HEADER_LEN;
265  header_read = 1;
266  } else if (bytes_left == 0) {
267  packet_type = LAST_PACKET;
268  } else {
269  packet_type = INTER_PACKET;
270  }
271  gspca_frame_add(gspca_dev, packet_type,
272  data, data_len);
273  /* If entire frame fits in one packet we still
274  need to add a LAST_PACKET */
275  if (packet_type == FIRST_PACKET &&
276  bytes_left == 0)
277  gspca_frame_add(gspca_dev, LAST_PACKET,
278  NULL, 0);
279  }
280  if (gspca_dev->present) {
281  /* acknowledge the frame */
282  mutex_lock(&gspca_dev->usb_lock);
283  ret = sq905_ack_frame(gspca_dev);
284  mutex_unlock(&gspca_dev->usb_lock);
285  if (ret < 0)
286  goto quit_stream;
287  }
288  }
289 quit_stream:
290  if (gspca_dev->present) {
291  mutex_lock(&gspca_dev->usb_lock);
292  sq905_command(gspca_dev, SQ905_CLEAR);
293  mutex_unlock(&gspca_dev->usb_lock);
294  }
295  kfree(buffer);
296 }
297 
298 /* This function is called at probe time just before sd_init */
299 static int sd_config(struct gspca_dev *gspca_dev,
300  const struct usb_device_id *id)
301 {
302  struct cam *cam = &gspca_dev->cam;
303  struct sd *dev = (struct sd *) gspca_dev;
304 
305  /* We don't use the buffer gspca allocates so make it small. */
306  cam->bulk = 1;
307  cam->bulk_size = 64;
308 
309  INIT_WORK(&dev->work_struct, sq905_dostream);
310 
311  return 0;
312 }
313 
314 /* called on streamoff with alt==0 and on disconnect */
315 /* the usb_lock is held at entry - restore on exit */
316 static void sd_stop0(struct gspca_dev *gspca_dev)
317 {
318  struct sd *dev = (struct sd *) gspca_dev;
319 
320  /* wait for the work queue to terminate */
321  mutex_unlock(&gspca_dev->usb_lock);
322  /* This waits for sq905_dostream to finish */
324  dev->work_thread = NULL;
325  mutex_lock(&gspca_dev->usb_lock);
326 }
327 
328 /* this function is called at probe and resume time */
329 static int sd_init(struct gspca_dev *gspca_dev)
330 {
331  u32 ident;
332  int ret;
333 
334  /* connect to the camera and read
335  * the model ID and process that and put it away.
336  */
337  ret = sq905_command(gspca_dev, SQ905_CLEAR);
338  if (ret < 0)
339  return ret;
340  ret = sq905_command(gspca_dev, SQ905_ID);
341  if (ret < 0)
342  return ret;
343  ret = sq905_read_data(gspca_dev, gspca_dev->usb_buf, 4, 0);
344  if (ret < 0)
345  return ret;
346  /* usb_buf is allocated with kmalloc so is aligned.
347  * Camera model number is the right way round if we assume this
348  * reverse engineered ID is supposed to be big endian. */
349  ident = be32_to_cpup((__be32 *)gspca_dev->usb_buf);
350  ret = sq905_command(gspca_dev, SQ905_CLEAR);
351  if (ret < 0)
352  return ret;
353  PDEBUG(D_CONF, "SQ905 camera ID %08x detected", ident);
354  gspca_dev->cam.cam_mode = sq905_mode;
355  gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
356  if (!(ident & SQ905_HIRES_MASK))
357  gspca_dev->cam.nmodes--;
358 
359  if (ident & SQ905_ORIENTATION_MASK)
360  gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
361  else
362  gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
364  return 0;
365 }
366 
367 /* Set up for getting frames. */
368 static int sd_start(struct gspca_dev *gspca_dev)
369 {
370  struct sd *dev = (struct sd *) gspca_dev;
371  int ret;
372 
373  /* "Open the shutter" and set size, to start capture */
374  switch (gspca_dev->curr_mode) {
375  default:
376 /* case 2: */
377  PDEBUG(D_STREAM, "Start streaming at high resolution");
378  ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_HIGH);
379  break;
380  case 1:
381  PDEBUG(D_STREAM, "Start streaming at medium resolution");
382  ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_MED);
383  break;
384  case 0:
385  PDEBUG(D_STREAM, "Start streaming at low resolution");
386  ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_LOW);
387  }
388 
389  if (ret < 0) {
390  PDEBUG(D_ERR, "Start streaming command failed");
391  return ret;
392  }
393  /* Start the workqueue function to do the streaming */
395  queue_work(dev->work_thread, &dev->work_struct);
396 
397  return 0;
398 }
399 
400 /* Table of supported USB devices */
401 static const struct usb_device_id device_table[] = {
402  {USB_DEVICE(0x2770, 0x9120)},
403  {}
404 };
405 
406 MODULE_DEVICE_TABLE(usb, device_table);
407 
408 /* sub-driver description */
409 static const struct sd_desc sd_desc = {
410  .name = MODULE_NAME,
411  .config = sd_config,
412  .init = sd_init,
413  .start = sd_start,
414  .stop0 = sd_stop0,
415 };
416 
417 /* -- device connect -- */
418 static int sd_probe(struct usb_interface *intf,
419  const struct usb_device_id *id)
420 {
421  return gspca_dev_probe(intf, id,
422  &sd_desc,
423  sizeof(struct sd),
424  THIS_MODULE);
425 }
426 
427 static struct usb_driver sd_driver = {
428  .name = MODULE_NAME,
429  .id_table = device_table,
430  .probe = sd_probe,
431  .disconnect = gspca_disconnect,
432 #ifdef CONFIG_PM
433  .suspend = gspca_suspend,
434  .resume = gspca_resume,
435  .reset_resume = gspca_resume,
436 #endif
437 };
438 
439 module_usb_driver(sd_driver);