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sq905c.c
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1 /*
2  * SQ905C subdriver
3  *
4  * Copyright (C) 2009 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  *
23  * This driver uses work done in
24  * libgphoto2/camlibs/digigr8, Copyright (C) Theodore Kilgore.
25  *
26  * This driver has also used as a base the sq905c driver
27  * and may contain code fragments from it.
28  */
29 
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31 
32 #define MODULE_NAME "sq905c"
33 
34 #include <linux/workqueue.h>
35 #include <linux/slab.h>
36 #include "gspca.h"
37 
38 MODULE_AUTHOR("Theodore Kilgore <[email protected]>");
39 MODULE_DESCRIPTION("GSPCA/SQ905C USB Camera Driver");
40 MODULE_LICENSE("GPL");
41 
42 /* Default timeouts, in ms */
43 #define SQ905C_CMD_TIMEOUT 500
44 #define SQ905C_DATA_TIMEOUT 1000
45 
46 /* Maximum transfer size to use. */
47 #define SQ905C_MAX_TRANSFER 0x8000
48 
49 #define FRAME_HEADER_LEN 0x50
50 
51 /* Commands. These go in the "value" slot. */
52 #define SQ905C_CLEAR 0xa0 /* clear everything */
53 #define SQ905C_GET_ID 0x14f4 /* Read version number */
54 #define SQ905C_CAPTURE_LOW 0xa040 /* Starts capture at 160x120 */
55 #define SQ905C_CAPTURE_MED 0x1440 /* Starts capture at 320x240 */
56 #define SQ905C_CAPTURE_HI 0x2840 /* Starts capture at 320x240 */
57 
58 /* For capture, this must go in the "index" slot. */
59 #define SQ905C_CAPTURE_INDEX 0x110f
60 
61 /* Structure to hold all of our device specific stuff */
62 struct sd {
63  struct gspca_dev gspca_dev; /* !! must be the first item */
64  const struct v4l2_pix_format *cap_mode;
65  /* Driver stuff */
66  struct work_struct work_struct;
68 };
69 
70 /*
71  * Most of these cameras will do 640x480 and 320x240. 160x120 works
72  * in theory but gives very poor output. Therefore, not supported.
73  * The 0x2770:0x9050 cameras have max resolution of 320x240.
74  */
75 static struct v4l2_pix_format sq905c_mode[] = {
77  .bytesperline = 320,
78  .sizeimage = 320 * 240,
79  .colorspace = V4L2_COLORSPACE_SRGB,
80  .priv = 0},
82  .bytesperline = 640,
83  .sizeimage = 640 * 480,
84  .colorspace = V4L2_COLORSPACE_SRGB,
85  .priv = 0}
86 };
87 
88 /* Send a command to the camera. */
89 static int sq905c_command(struct gspca_dev *gspca_dev, u16 command, u16 index)
90 {
91  int ret;
92 
93  ret = usb_control_msg(gspca_dev->dev,
94  usb_sndctrlpipe(gspca_dev->dev, 0),
95  USB_REQ_SYNCH_FRAME, /* request */
97  command, index, NULL, 0,
99  if (ret < 0) {
100  pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
101  return ret;
102  }
103 
104  return 0;
105 }
106 
107 static int sq905c_read(struct gspca_dev *gspca_dev, u16 command, u16 index,
108  int size)
109 {
110  int ret;
111 
112  ret = usb_control_msg(gspca_dev->dev,
113  usb_rcvctrlpipe(gspca_dev->dev, 0),
114  USB_REQ_SYNCH_FRAME, /* request */
116  command, index, gspca_dev->usb_buf, size,
118  if (ret < 0) {
119  pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
120  return ret;
121  }
122 
123  return 0;
124 }
125 
126 /*
127  * This function is called as a workqueue function and runs whenever the camera
128  * is streaming data. Because it is a workqueue function it is allowed to sleep
129  * so we can use synchronous USB calls. To avoid possible collisions with other
130  * threads attempting to use gspca_dev->usb_buf we take the usb_lock when
131  * performing USB operations using it. In practice we don't really need this
132  * as the camera doesn't provide any controls.
133  */
134 static void sq905c_dostream(struct work_struct *work)
135 {
136  struct sd *dev = container_of(work, struct sd, work_struct);
137  struct gspca_dev *gspca_dev = &dev->gspca_dev;
138  int bytes_left; /* bytes remaining in current frame. */
139  int data_len; /* size to use for the next read. */
140  int act_len;
141  int packet_type;
142  int ret;
143  u8 *buffer;
144 
146  if (!buffer) {
147  pr_err("Couldn't allocate USB buffer\n");
148  goto quit_stream;
149  }
150 
151  while (gspca_dev->present && gspca_dev->streaming) {
152 #ifdef CONFIG_PM
153  if (gspca_dev->frozen)
154  break;
155 #endif
156  /* Request the header, which tells the size to download */
157  ret = usb_bulk_msg(gspca_dev->dev,
158  usb_rcvbulkpipe(gspca_dev->dev, 0x81),
159  buffer, FRAME_HEADER_LEN, &act_len,
161  PDEBUG(D_STREAM,
162  "Got %d bytes out of %d for header",
163  act_len, FRAME_HEADER_LEN);
164  if (ret < 0 || act_len < FRAME_HEADER_LEN)
165  goto quit_stream;
166  /* size is read from 4 bytes starting 0x40, little endian */
167  bytes_left = buffer[0x40]|(buffer[0x41]<<8)|(buffer[0x42]<<16)
168  |(buffer[0x43]<<24);
169  PDEBUG(D_STREAM, "bytes_left = 0x%x", bytes_left);
170  /* We keep the header. It has other information, too. */
171  packet_type = FIRST_PACKET;
172  gspca_frame_add(gspca_dev, packet_type,
173  buffer, FRAME_HEADER_LEN);
174  while (bytes_left > 0 && gspca_dev->present) {
175  data_len = bytes_left > SQ905C_MAX_TRANSFER ?
176  SQ905C_MAX_TRANSFER : bytes_left;
177  ret = usb_bulk_msg(gspca_dev->dev,
178  usb_rcvbulkpipe(gspca_dev->dev, 0x81),
179  buffer, data_len, &act_len,
181  if (ret < 0 || act_len < data_len)
182  goto quit_stream;
183  PDEBUG(D_STREAM,
184  "Got %d bytes out of %d for frame",
185  data_len, bytes_left);
186  bytes_left -= data_len;
187  if (bytes_left == 0)
188  packet_type = LAST_PACKET;
189  else
190  packet_type = INTER_PACKET;
191  gspca_frame_add(gspca_dev, packet_type,
192  buffer, data_len);
193  }
194  }
195 quit_stream:
196  if (gspca_dev->present) {
197  mutex_lock(&gspca_dev->usb_lock);
198  sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
199  mutex_unlock(&gspca_dev->usb_lock);
200  }
201  kfree(buffer);
202 }
203 
204 /* This function is called at probe time just before sd_init */
205 static int sd_config(struct gspca_dev *gspca_dev,
206  const struct usb_device_id *id)
207 {
208  struct cam *cam = &gspca_dev->cam;
209  struct sd *dev = (struct sd *) gspca_dev;
210  int ret;
211 
212  PDEBUG(D_PROBE,
213  "SQ9050 camera detected"
214  " (vid/pid 0x%04X:0x%04X)", id->idVendor, id->idProduct);
215 
216  ret = sq905c_command(gspca_dev, SQ905C_GET_ID, 0);
217  if (ret < 0) {
218  PDEBUG(D_ERR, "Get version command failed");
219  return ret;
220  }
221 
222  ret = sq905c_read(gspca_dev, 0xf5, 0, 20);
223  if (ret < 0) {
224  PDEBUG(D_ERR, "Reading version command failed");
225  return ret;
226  }
227  /* Note we leave out the usb id and the manufacturing date */
228  PDEBUG(D_PROBE,
229  "SQ9050 ID string: %02x - %*ph",
230  gspca_dev->usb_buf[3], 6, gspca_dev->usb_buf + 14);
231 
232  cam->cam_mode = sq905c_mode;
233  cam->nmodes = 2;
234  if (gspca_dev->usb_buf[15] == 0)
235  cam->nmodes = 1;
236  /* We don't use the buffer gspca allocates so make it small. */
237  cam->bulk_size = 32;
238  cam->bulk = 1;
239  INIT_WORK(&dev->work_struct, sq905c_dostream);
240  return 0;
241 }
242 
243 /* called on streamoff with alt==0 and on disconnect */
244 /* the usb_lock is held at entry - restore on exit */
245 static void sd_stop0(struct gspca_dev *gspca_dev)
246 {
247  struct sd *dev = (struct sd *) gspca_dev;
248 
249  /* wait for the work queue to terminate */
250  mutex_unlock(&gspca_dev->usb_lock);
251  /* This waits for sq905c_dostream to finish */
253  dev->work_thread = NULL;
254  mutex_lock(&gspca_dev->usb_lock);
255 }
256 
257 /* this function is called at probe and resume time */
258 static int sd_init(struct gspca_dev *gspca_dev)
259 {
260  int ret;
261 
262  /* connect to the camera and reset it. */
263  ret = sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
264  return ret;
265 }
266 
267 /* Set up for getting frames. */
268 static int sd_start(struct gspca_dev *gspca_dev)
269 {
270  struct sd *dev = (struct sd *) gspca_dev;
271  int ret;
272 
273  dev->cap_mode = gspca_dev->cam.cam_mode;
274  /* "Open the shutter" and set size, to start capture */
275  switch (gspca_dev->width) {
276  case 640:
277  PDEBUG(D_STREAM, "Start streaming at high resolution");
278  dev->cap_mode++;
279  ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_HI,
281  break;
282  default: /* 320 */
283  PDEBUG(D_STREAM, "Start streaming at medium resolution");
284  ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_MED,
286  }
287 
288  if (ret < 0) {
289  PDEBUG(D_ERR, "Start streaming command failed");
290  return ret;
291  }
292  /* Start the workqueue function to do the streaming */
294  queue_work(dev->work_thread, &dev->work_struct);
295 
296  return 0;
297 }
298 
299 /* Table of supported USB devices */
300 static const struct usb_device_id device_table[] = {
301  {USB_DEVICE(0x2770, 0x905c)},
302  {USB_DEVICE(0x2770, 0x9050)},
303  {USB_DEVICE(0x2770, 0x9051)},
304  {USB_DEVICE(0x2770, 0x9052)},
305  {USB_DEVICE(0x2770, 0x913d)},
306  {}
307 };
308 
309 MODULE_DEVICE_TABLE(usb, device_table);
310 
311 /* sub-driver description */
312 static const struct sd_desc sd_desc = {
313  .name = MODULE_NAME,
314  .config = sd_config,
315  .init = sd_init,
316  .start = sd_start,
317  .stop0 = sd_stop0,
318 };
319 
320 /* -- device connect -- */
321 static int sd_probe(struct usb_interface *intf,
322  const struct usb_device_id *id)
323 {
324  return gspca_dev_probe(intf, id,
325  &sd_desc,
326  sizeof(struct sd),
327  THIS_MODULE);
328 }
329 
330 static struct usb_driver sd_driver = {
331  .name = MODULE_NAME,
332  .id_table = device_table,
333  .probe = sd_probe,
334  .disconnect = gspca_disconnect,
335 #ifdef CONFIG_PM
336  .suspend = gspca_suspend,
337  .resume = gspca_resume,
338  .reset_resume = gspca_resume,
339 #endif
340 };
341 
342 module_usb_driver(sd_driver);