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diff --git a/Documentation/video4linux/sn9c102.txt b/Documentation/video4linux/sn9c102.txt
index 8cda472db36d..2913da3d0878 100644
--- a/Documentation/video4linux/sn9c102.txt
+++ b/Documentation/video4linux/sn9c102.txt
@@ -1,5 +1,5 @@
1 1
2 SN9C10x PC Camera Controllers 2 SN9C1xx PC Camera Controllers
3 Driver for Linux 3 Driver for Linux
4 ============================= 4 =============================
5 5
@@ -53,20 +53,14 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
53 53
544. Overview and features 544. Overview and features
55======================== 55========================
56This driver attempts to support the video interface of the devices mounting the 56This driver attempts to support the video interface of the devices assembling
57SONiX SN9C101, SN9C102 and SN9C103 PC Camera Controllers. 57the SONiX SN9C101, SN9C102, SN9C103, SN9C105 and SN9C120 PC Camera Controllers
58 58("SN9C1xx" from now on).
59It's worth to note that SONiX has never collaborated with the author during the
60development of this project, despite several requests for enough detailed
61specifications of the register tables, compression engine and video data format
62of the above chips. Nevertheless, these informations are no longer necessary,
63because all the aspects related to these chips are known and have been
64described in detail in this documentation.
65 59
66The driver relies on the Video4Linux2 and USB core modules. It has been 60The driver relies on the Video4Linux2 and USB core modules. It has been
67designed to run properly on SMP systems as well. 61designed to run properly on SMP systems as well.
68 62
69The latest version of the SN9C10x driver can be found at the following URL: 63The latest version of the SN9C1xx driver can be found at the following URL:
70http://www.linux-projects.org/ 64http://www.linux-projects.org/
71 65
72Some of the features of the driver are: 66Some of the features of the driver are:
@@ -85,11 +79,11 @@ Some of the features of the driver are:
85 high compression quality (see also "Notes for V4L2 application developers" 79 high compression quality (see also "Notes for V4L2 application developers"
86 and "Video frame formats" paragraphs); 80 and "Video frame formats" paragraphs);
87- full support for the capabilities of many of the possible image sensors that 81- full support for the capabilities of many of the possible image sensors that
88 can be connected to the SN9C10x bridges, including, for instance, red, green, 82 can be connected to the SN9C1xx bridges, including, for instance, red, green,
89 blue and global gain adjustments and exposure (see "Supported devices" 83 blue and global gain adjustments and exposure (see "Supported devices"
90 paragraph for details); 84 paragraph for details);
91- use of default color settings for sunlight conditions; 85- use of default color settings for sunlight conditions;
92- dynamic I/O interface for both SN9C10x and image sensor control and 86- dynamic I/O interface for both SN9C1xx and image sensor control and
93 monitoring (see "Optional device control through 'sysfs'" paragraph); 87 monitoring (see "Optional device control through 'sysfs'" paragraph);
94- dynamic driver control thanks to various module parameters (see "Module 88- dynamic driver control thanks to various module parameters (see "Module
95 parameters" paragraph); 89 parameters" paragraph);
@@ -130,8 +124,8 @@ necessary:
130 CONFIG_USB_UHCI_HCD=m 124 CONFIG_USB_UHCI_HCD=m
131 CONFIG_USB_OHCI_HCD=m 125 CONFIG_USB_OHCI_HCD=m
132 126
133The SN9C103 controller also provides a built-in microphone interface. It is 127The SN9C103, SN9c105 and SN9C120 controllers also provide a built-in microphone
134supported by the USB Audio driver thanks to the ALSA API: 128interface. It is supported by the USB Audio driver thanks to the ALSA API:
135 129
136 # Sound 130 # Sound
137 # 131 #
@@ -155,18 +149,27 @@ And finally:
1556. Module loading 1496. Module loading
156================= 150=================
157To use the driver, it is necessary to load the "sn9c102" module into memory 151To use the driver, it is necessary to load the "sn9c102" module into memory
158after every other module required: "videodev", "usbcore" and, depending on 152after every other module required: "videodev", "v4l2_common", "compat_ioctl32",
159the USB host controller you have, "ehci-hcd", "uhci-hcd" or "ohci-hcd". 153"usbcore" and, depending on the USB host controller you have, "ehci-hcd",
154"uhci-hcd" or "ohci-hcd".
160 155
161Loading can be done as shown below: 156Loading can be done as shown below:
162 157
163 [root@localhost home]# modprobe sn9c102 158 [root@localhost home]# modprobe sn9c102
164 159
165At this point the devices should be recognized. You can invoke "dmesg" to 160Note that the module is called "sn9c102" for historic reasons, althought it
166analyze kernel messages and verify that the loading process has gone well: 161does not just support the SN9C102.
162
163At this point all the devices supported by the driver and connected to the USB
164ports should be recognized. You can invoke "dmesg" to analyze kernel messages
165and verify that the loading process has gone well:
167 166
168 [user@localhost home]$ dmesg 167 [user@localhost home]$ dmesg
169 168
169or, to isolate all the kernel messages generated by the driver:
170
171 [user@localhost home]$ dmesg | grep sn9c102
172
170 173
1717. Module parameters 1747. Module parameters
172==================== 175====================
@@ -198,10 +201,11 @@ Default: 0
198------------------------------------------------------------------------------- 201-------------------------------------------------------------------------------
199Name: frame_timeout 202Name: frame_timeout
200Type: uint array (min = 0, max = 64) 203Type: uint array (min = 0, max = 64)
201Syntax: <n[,...]> 204Syntax: <0|n[,...]>
202Description: Timeout for a video frame in seconds. This parameter is 205Description: Timeout for a video frame in seconds before returning an I/O
203 specific for each detected camera. This parameter can be 206 error; 0 for infinity. This parameter is specific for each
204 changed at runtime thanks to the /sys filesystem interface. 207 detected camera and can be changed at runtime thanks to the
208 /sys filesystem interface.
205Default: 2 209Default: 2
206------------------------------------------------------------------------------- 210-------------------------------------------------------------------------------
207Name: debug 211Name: debug
@@ -223,20 +227,21 @@ Default: 2
2238. Optional device control through "sysfs" [1] 2278. Optional device control through "sysfs" [1]
224========================================== 228==========================================
225If the kernel has been compiled with the CONFIG_VIDEO_ADV_DEBUG option enabled, 229If the kernel has been compiled with the CONFIG_VIDEO_ADV_DEBUG option enabled,
226it is possible to read and write both the SN9C10x and the image sensor 230it is possible to read and write both the SN9C1xx and the image sensor
227registers by using the "sysfs" filesystem interface. 231registers by using the "sysfs" filesystem interface.
228 232
229Every time a supported device is recognized, a write-only file named "green" is 233Every time a supported device is recognized, a write-only file named "green" is
230created in the /sys/class/video4linux/videoX directory. You can set the green 234created in the /sys/class/video4linux/videoX directory. You can set the green
231channel's gain by writing the desired value to it. The value may range from 0 235channel's gain by writing the desired value to it. The value may range from 0
232to 15 for SN9C101 or SN9C102 bridges, from 0 to 127 for SN9C103 bridges. 236to 15 for the SN9C101 or SN9C102 bridges, from 0 to 127 for the SN9C103,
233Similarly, only for SN9C103 controllers, blue and red gain control files are 237SN9C105 and SN9C120 bridges.
234available in the same directory, for which accepted values may range from 0 to 238Similarly, only for the SN9C103, SN9C105 and SN9120 controllers, blue and red
235127. 239gain control files are available in the same directory, for which accepted
240values may range from 0 to 127.
236 241
237There are other four entries in the directory above for each registered camera: 242There are other four entries in the directory above for each registered camera:
238"reg", "val", "i2c_reg" and "i2c_val". The first two files control the 243"reg", "val", "i2c_reg" and "i2c_val". The first two files control the
239SN9C10x bridge, while the other two control the sensor chip. "reg" and 244SN9C1xx bridge, while the other two control the sensor chip. "reg" and
240"i2c_reg" hold the values of the current register index where the following 245"i2c_reg" hold the values of the current register index where the following
241reading/writing operations are addressed at through "val" and "i2c_val". Their 246reading/writing operations are addressed at through "val" and "i2c_val". Their
242use is not intended for end-users. Note that "i2c_reg" and "i2c_val" will not 247use is not intended for end-users. Note that "i2c_reg" and "i2c_val" will not
@@ -259,61 +264,84 @@ Now let's set the green gain's register of the SN9C101 or SN9C102 chips to 2:
259 [root@localhost #] echo 0x11 > reg 264 [root@localhost #] echo 0x11 > reg
260 [root@localhost #] echo 2 > val 265 [root@localhost #] echo 2 > val
261 266
262Note that the SN9C10x always returns 0 when some of its registers are read. 267Note that the SN9C1xx always returns 0 when some of its registers are read.
263To avoid race conditions, all the I/O accesses to the above files are 268To avoid race conditions, all the I/O accesses to the above files are
264serialized. 269serialized.
265
266The sysfs interface also provides the "frame_header" entry, which exports the 270The sysfs interface also provides the "frame_header" entry, which exports the
267frame header of the most recent requested and captured video frame. The header 271frame header of the most recent requested and captured video frame. The header
268is always 18-bytes long and is appended to every video frame by the SN9C10x 272is always 18-bytes long and is appended to every video frame by the SN9C1xx
269controllers. As an example, this additional information can be used by the user 273controllers. As an example, this additional information can be used by the user
270application for implementing auto-exposure features via software. 274application for implementing auto-exposure features via software.
271 275
272The following table describes the frame header: 276The following table describes the frame header exported by the SN9C101 and
273 277SN9C102:
274Byte # Value Description 278
275------ ----- ----------- 279Byte # Value or bits Description
2760x00 0xFF Frame synchronisation pattern. 280------ ------------- -----------
2770x01 0xFF Frame synchronisation pattern. 2810x00 0xFF Frame synchronisation pattern
2780x02 0x00 Frame synchronisation pattern. 2820x01 0xFF Frame synchronisation pattern
2790x03 0xC4 Frame synchronisation pattern. 2830x02 0x00 Frame synchronisation pattern
2800x04 0xC4 Frame synchronisation pattern. 2840x03 0xC4 Frame synchronisation pattern
2810x05 0x96 Frame synchronisation pattern. 2850x04 0xC4 Frame synchronisation pattern
2820x06 0xXX Unknown meaning. The exact value depends on the chip; 2860x05 0x96 Frame synchronisation pattern
283 possible values are 0x00, 0x01 and 0x20. 2870x06 [3:0] Read channel gain control = (1+R_GAIN/8)
2840x07 0xXX Variable value, whose bits are ff00uzzc, where ff is a 288 [7:4] Blue channel gain control = (1+B_GAIN/8)
285 frame counter, u is unknown, zz is a size indicator 2890x07 [ 0 ] Compression mode. 0=No compression, 1=Compression enabled
286 (00 = VGA, 01 = SIF, 10 = QSIF) and c stands for 290 [2:1] Maximum scale factor for compression
287 "compression enabled" (1 = yes, 0 = no). 291 [ 3 ] 1 = USB fifo(2K bytes) is full
2880x08 0xXX Brightness sum inside Auto-Exposure area (low-byte). 292 [ 4 ] 1 = Digital gain is finish
2890x09 0xXX Brightness sum inside Auto-Exposure area (high-byte). 293 [ 5 ] 1 = Exposure is finish
290 For a pure white image, this number will be equal to 500 294 [7:6] Frame index
291 times the area of the specified AE area. For images 2950x08 [7:0] Y sum inside Auto-Exposure area (low-byte)
292 that are not pure white, the value scales down according 2960x09 [7:0] Y sum inside Auto-Exposure area (high-byte)
293 to relative whiteness. 297 where Y sum = (R/4 + 5G/16 + B/8) / 32
2940x0A 0xXX Brightness sum outside Auto-Exposure area (low-byte). 2980x0A [7:0] Y sum outside Auto-Exposure area (low-byte)
2950x0B 0xXX Brightness sum outside Auto-Exposure area (high-byte). 2990x0B [7:0] Y sum outside Auto-Exposure area (high-byte)
296 For a pure white image, this number will be equal to 125 300 where Y sum = (R/4 + 5G/16 + B/8) / 128
297 times the area outside of the specified AE area. For 3010x0C 0xXX Not used
298 images that are not pure white, the value scales down 3020x0D 0xXX Not used
299 according to relative whiteness. 3030x0E 0xXX Not used
300 according to relative whiteness. 3040x0F 0xXX Not used
301 3050x10 0xXX Not used
302The following bytes are used by the SN9C103 bridge only: 3060x11 0xXX Not used
303 307
3040x0C 0xXX Unknown meaning 308The following table describes the frame header exported by the SN9C103:
3050x0D 0xXX Unknown meaning 309
3060x0E 0xXX Unknown meaning 310Byte # Value or bits Description
3070x0F 0xXX Unknown meaning 311------ ------------- -----------
3080x10 0xXX Unknown meaning 3120x00 0xFF Frame synchronisation pattern
3090x11 0xXX Unknown meaning 3130x01 0xFF Frame synchronisation pattern
3140x02 0x00 Frame synchronisation pattern
3150x03 0xC4 Frame synchronisation pattern
3160x04 0xC4 Frame synchronisation pattern
3170x05 0x96 Frame synchronisation pattern
3180x06 [6:0] Read channel gain control = (1/2+R_GAIN/64)
3190x07 [6:0] Blue channel gain control = (1/2+B_GAIN/64)
320 [7:4]
3210x08 [ 0 ] Compression mode. 0=No compression, 1=Compression enabled
322 [2:1] Maximum scale factor for compression
323 [ 3 ] 1 = USB fifo(2K bytes) is full
324 [ 4 ] 1 = Digital gain is finish
325 [ 5 ] 1 = Exposure is finish
326 [7:6] Frame index
3270x09 [7:0] Y sum inside Auto-Exposure area (low-byte)
3280x0A [7:0] Y sum inside Auto-Exposure area (high-byte)
329 where Y sum = (R/4 + 5G/16 + B/8) / 32
3300x0B [7:0] Y sum outside Auto-Exposure area (low-byte)
3310x0C [7:0] Y sum outside Auto-Exposure area (high-byte)
332 where Y sum = (R/4 + 5G/16 + B/8) / 128
3330x0D [1:0] Audio frame number
334 [ 2 ] 1 = Audio is recording
3350x0E [7:0] Audio summation (low-byte)
3360x0F [7:0] Audio summation (high-byte)
3370x10 [7:0] Audio sample count
3380x11 [7:0] Audio peak data in audio frame
310 339
311The AE area (sx, sy, ex, ey) in the active window can be set by programming the 340The AE area (sx, sy, ex, ey) in the active window can be set by programming the
312registers 0x1c, 0x1d, 0x1e and 0x1f of the SN9C10x controllers, where one unit 341registers 0x1c, 0x1d, 0x1e and 0x1f of the SN9C1xx controllers, where one unit
313corresponds to 32 pixels. 342corresponds to 32 pixels.
314 343
315[1] Part of the meaning of the frame header has been documented by Bertrik 344[1] The frame headers exported by the SN9C105 and SN9C120 are not described.
316 Sikken.
317 345
318 346
3199. Supported devices 3479. Supported devices
@@ -323,15 +351,19 @@ here. They have never collaborated with the author, so no advertising.
323 351
324From the point of view of a driver, what unambiguously identify a device are 352From the point of view of a driver, what unambiguously identify a device are
325its vendor and product USB identifiers. Below is a list of known identifiers of 353its vendor and product USB identifiers. Below is a list of known identifiers of
326devices mounting the SN9C10x PC camera controllers: 354devices assembling the SN9C1xx PC camera controllers:
327 355
328Vendor ID Product ID 356Vendor ID Product ID
329--------- ---------- 357--------- ----------
3580x0471 0x0327
3590x0471 0x0328
3300x0c45 0x6001 3600x0c45 0x6001
3310x0c45 0x6005 3610x0c45 0x6005
3320x0c45 0x6007 3620x0c45 0x6007
3330x0c45 0x6009 3630x0c45 0x6009
3340x0c45 0x600d 3640x0c45 0x600d
3650x0c45 0x6011
3660x0c45 0x6019
3350x0c45 0x6024 3670x0c45 0x6024
3360x0c45 0x6025 3680x0c45 0x6025
3370x0c45 0x6028 3690x0c45 0x6028
@@ -342,6 +374,7 @@ Vendor ID Product ID
3420x0c45 0x602d 3740x0c45 0x602d
3430x0c45 0x602e 3750x0c45 0x602e
3440x0c45 0x6030 3760x0c45 0x6030
3770x0c45 0x603f
3450x0c45 0x6080 3780x0c45 0x6080
3460x0c45 0x6082 3790x0c45 0x6082
3470x0c45 0x6083 3800x0c45 0x6083
@@ -368,24 +401,40 @@ Vendor ID Product ID
3680x0c45 0x60bb 4010x0c45 0x60bb
3690x0c45 0x60bc 4020x0c45 0x60bc
3700x0c45 0x60be 4030x0c45 0x60be
4040x0c45 0x60c0
4050x0c45 0x60c8
4060x0c45 0x60cc
4070x0c45 0x60ea
4080x0c45 0x60ec
4090x0c45 0x60fa
4100x0c45 0x60fb
4110x0c45 0x60fc
4120x0c45 0x60fe
4130x0c45 0x6130
4140x0c45 0x613a
4150x0c45 0x613b
4160x0c45 0x613c
4170x0c45 0x613e
371 418
372The list above does not imply that all those devices work with this driver: up 419The list above does not imply that all those devices work with this driver: up
373until now only the ones that mount the following image sensors are supported; 420until now only the ones that assemble the following image sensors are
374kernel messages will always tell you whether this is the case: 421supported; kernel messages will always tell you whether this is the case (see
422"Module loading" paragraph):
375 423
376Model Manufacturer 424Model Manufacturer
377----- ------------ 425----- ------------
378HV7131D Hynix Semiconductor, Inc. 426HV7131D Hynix Semiconductor, Inc.
379MI-0343 Micron Technology, Inc. 427MI-0343 Micron Technology, Inc.
380OV7630 OmniVision Technologies, Inc. 428OV7630 OmniVision Technologies, Inc.
429OV7660 OmniVision Technologies, Inc.
381PAS106B PixArt Imaging, Inc. 430PAS106B PixArt Imaging, Inc.
382PAS202BCA PixArt Imaging, Inc. 431PAS202BCA PixArt Imaging, Inc.
383PAS202BCB PixArt Imaging, Inc. 432PAS202BCB PixArt Imaging, Inc.
384TAS5110C1B Taiwan Advanced Sensor Corporation 433TAS5110C1B Taiwan Advanced Sensor Corporation
385TAS5130D1B Taiwan Advanced Sensor Corporation 434TAS5130D1B Taiwan Advanced Sensor Corporation
386 435
387All the available control settings of each image sensor are supported through 436Some of the available control settings of each image sensor are supported
388the V4L2 interface. 437through the V4L2 interface.
389 438
390Donations of new models for further testing and support would be much 439Donations of new models for further testing and support would be much
391appreciated. Non-available hardware will not be supported by the author of this 440appreciated. Non-available hardware will not be supported by the author of this
@@ -429,12 +478,15 @@ supplied by this driver).
429 478
43011. Video frame formats [1] 47911. Video frame formats [1]
431======================= 480=======================
432The SN9C10x PC Camera Controllers can send images in two possible video 481The SN9C1xx PC Camera Controllers can send images in two possible video
433formats over the USB: either native "Sequential RGB Bayer" or Huffman 482formats over the USB: either native "Sequential RGB Bayer" or compressed.
434compressed. The latter is used to achieve high frame rates. The current video 483The compression is used to achieve high frame rates. With regard to the
435format may be selected or queried from the user application by calling the 484SN9C101, SN9C102 and SN9C103, the compression is based on the Huffman encoding
436VIDIOC_S_FMT or VIDIOC_G_FMT ioctl's, as described in the V4L2 API 485algorithm described below, while the SN9C105 and SN9C120 the compression is
437specifications. 486based on the JPEG standard.
487The current video format may be selected or queried from the user application
488by calling the VIDIOC_S_FMT or VIDIOC_G_FMT ioctl's, as described in the V4L2
489API specifications.
438 490
439The name "Sequential Bayer" indicates the organization of the red, green and 491The name "Sequential Bayer" indicates the organization of the red, green and
440blue pixels in one video frame. Each pixel is associated with a 8-bit long 492blue pixels in one video frame. Each pixel is associated with a 8-bit long
@@ -447,14 +499,14 @@ G[m] R[m+1] G[m+2] R[m+2] ... G[2m-2] R[2m-1]
447... G[n(m-2)] R[n(m-1)] 499... G[n(m-2)] R[n(m-1)]
448 500
449The above matrix also represents the sequential or progressive read-out mode of 501The above matrix also represents the sequential or progressive read-out mode of
450the (n, m) Bayer color filter array used in many CCD/CMOS image sensors. 502the (n, m) Bayer color filter array used in many CCD or CMOS image sensors.
451 503
452One compressed video frame consists of a bitstream that encodes for every R, G, 504The Huffman compressed video frame consists of a bitstream that encodes for
453or B pixel the difference between the value of the pixel itself and some 505every R, G, or B pixel the difference between the value of the pixel itself and
454reference pixel value. Pixels are organised in the Bayer pattern and the Bayer 506some reference pixel value. Pixels are organised in the Bayer pattern and the
455sub-pixels are tracked individually and alternatingly. For example, in the 507Bayer sub-pixels are tracked individually and alternatingly. For example, in
456first line values for the B and G1 pixels are alternatingly encoded, while in 508the first line values for the B and G1 pixels are alternatingly encoded, while
457the second line values for the G2 and R pixels are alternatingly encoded. 509in the second line values for the G2 and R pixels are alternatingly encoded.
458 510
459The pixel reference value is calculated as follows: 511The pixel reference value is calculated as follows:
460- the 4 top left pixels are encoded in raw uncompressed 8-bit format; 512- the 4 top left pixels are encoded in raw uncompressed 8-bit format;
@@ -470,8 +522,9 @@ The pixel reference value is calculated as follows:
470 decoding. 522 decoding.
471 523
472The algorithm purely describes the conversion from compressed Bayer code used 524The algorithm purely describes the conversion from compressed Bayer code used
473in the SN9C10x chips to uncompressed Bayer. Additional steps are required to 525in the SN9C101, SN9C102 and SN9C103 chips to uncompressed Bayer. Additional
474convert this to a color image (i.e. a color interpolation algorithm). 526steps are required to convert this to a color image (i.e. a color interpolation
527algorithm).
475 528
476The following Huffman codes have been found: 529The following Huffman codes have been found:
4770: +0 (relative to reference pixel value) 5300: +0 (relative to reference pixel value)
@@ -506,13 +559,18 @@ order):
506- Philippe Coval for having helped testing the PAS202BCA image sensor; 559- Philippe Coval for having helped testing the PAS202BCA image sensor;
507- Joao Rodrigo Fuzaro, Joao Limirio, Claudio Filho and Caio Begotti for the 560- Joao Rodrigo Fuzaro, Joao Limirio, Claudio Filho and Caio Begotti for the
508 donation of a webcam; 561 donation of a webcam;
562- Dennis Heitmann for the donation of a webcam;
509- Jon Hollstrom for the donation of a webcam; 563- Jon Hollstrom for the donation of a webcam;
564- Nick McGill for the donation of a webcam;
510- Carlos Eduardo Medaglia Dyonisio, who added the support for the PAS202BCB 565- Carlos Eduardo Medaglia Dyonisio, who added the support for the PAS202BCB
511 image sensor; 566 image sensor;
512- Stefano Mozzi, who donated 45 EU; 567- Stefano Mozzi, who donated 45 EU;
513- Andrew Pearce for the donation of a webcam; 568- Andrew Pearce for the donation of a webcam;
569- John Pullan for the donation of a webcam;
514- Bertrik Sikken, who reverse-engineered and documented the Huffman compression 570- Bertrik Sikken, who reverse-engineered and documented the Huffman compression
515 algorithm used in the SN9C10x controllers and implemented the first decoder; 571 algorithm used in the SN9C101, SN9C102 and SN9C103 controllers and
572 implemented the first decoder;
516- Mizuno Takafumi for the donation of a webcam; 573- Mizuno Takafumi for the donation of a webcam;
517- an "anonymous" donator (who didn't want his name to be revealed) for the 574- an "anonymous" donator (who didn't want his name to be revealed) for the
518 donation of a webcam. 575 donation of a webcam.
576- an anonymous donator for the donation of four webcams.