diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-12-30 20:41:32 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-12-30 20:41:32 -0500 |
commit | f54a6ec0fd85002d94d05b4bb679508eeb066683 (patch) | |
tree | 0f24dd66cce563d2c5e7656c2489e5b96eef31f9 /Documentation/video4linux | |
parent | 5ed1836814d908f45cafde0e79cb85314ab9d41d (diff) | |
parent | 134179823b3ca9c8b98e0631906459dbb022ff9b (diff) |
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (583 commits)
V4L/DVB (10130): use USB API functions rather than constants
V4L/DVB (10129): dvb: remove deprecated use of RW_LOCK_UNLOCKED in frontends
V4L/DVB (10128): modify V4L documentation to be a valid XHTML
V4L/DVB (10127): stv06xx: Avoid having y unitialized
V4L/DVB (10125): em28xx: Don't do AC97 vendor detection for i2s audio devices
V4L/DVB (10124): em28xx: expand output formats available
V4L/DVB (10123): em28xx: fix reversed definitions of I2S audio modes
V4L/DVB (10122): em28xx: don't load em28xx-alsa for em2870 based devices
V4L/DVB (10121): em28xx: remove worthless Pinnacle PCTV HD Mini 80e device profile
V4L/DVB (10120): em28xx: remove redundant Pinnacle Dazzle DVC 100 profile
V4L/DVB (10119): em28xx: fix corrupted XCLK value
V4L/DVB (10118): zoran: fix warning for a variable not used
V4L/DVB (10116): af9013: Fix gcc false warnings
V4L/DVB (10111a): usbvideo.h: remove an useless blank line
V4L/DVB (10111): quickcam_messenger.c: fix a warning
V4L/DVB (10110): v4l2-ioctl: Fix warnings when using .unlocked_ioctl = __video_ioctl2
V4L/DVB (10109): anysee: Fix usage of an unitialized function
V4L/DVB (10104): uvcvideo: Add support for video output devices
V4L/DVB (10102): uvcvideo: Ignore interrupt endpoint for built-in iSight webcams.
V4L/DVB (10101): uvcvideo: Fix bulk URB processing when the header is erroneous
...
Diffstat (limited to 'Documentation/video4linux')
-rw-r--r-- | Documentation/video4linux/API.html | 43 | ||||
-rw-r--r-- | Documentation/video4linux/CARDLIST.bttv | 7 | ||||
-rw-r--r-- | Documentation/video4linux/CARDLIST.cx23885 | 1 | ||||
-rw-r--r-- | Documentation/video4linux/CARDLIST.cx88 | 5 | ||||
-rw-r--r-- | Documentation/video4linux/CARDLIST.em28xx | 9 | ||||
-rw-r--r-- | Documentation/video4linux/CARDLIST.saa7134 | 3 | ||||
-rw-r--r-- | Documentation/video4linux/README.cx88 | 8 | ||||
-rw-r--r-- | Documentation/video4linux/gspca.txt | 19 | ||||
-rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 520 |
9 files changed, 585 insertions, 30 deletions
diff --git a/Documentation/video4linux/API.html b/Documentation/video4linux/API.html index afbe9ae7ee96..d749d41f647b 100644 --- a/Documentation/video4linux/API.html +++ b/Documentation/video4linux/API.html | |||
@@ -1,16 +1,27 @@ | |||
1 | <TITLE>V4L API</TITLE> | 1 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> |
2 | <H1>Video For Linux APIs</H1> | 2 | <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> |
3 | <table border=0> | 3 | <head> |
4 | <tr> | 4 | <meta content="text/html;charset=ISO-8859-2" http-equiv="Content-Type" /> |
5 | <td> | 5 | <title>V4L API</title> |
6 | <A HREF=http://www.linuxtv.org/downloads/video4linux/API/V4L1_API.html> | 6 | </head> |
7 | V4L original API</a> | 7 | <body> |
8 | </td><td> | 8 | <h1>Video For Linux APIs</h1> |
9 | Obsoleted by V4L2 API | 9 | <table border="0"> |
10 | </td></tr><tr><td> | 10 | <tr> |
11 | <A HREF=http://www.linuxtv.org/downloads/video4linux/API/V4L2_API> | 11 | <td> |
12 | V4L2 API</a> | 12 | <a href="http://www.linuxtv.org/downloads/video4linux/API/V4L1_API.html">V4L original API</a> |
13 | </td><td> | 13 | </td> |
14 | Should be used for new projects | 14 | <td> |
15 | </td></tr> | 15 | Obsoleted by V4L2 API |
16 | </table> | 16 | </td> |
17 | </tr> | ||
18 | <tr> | ||
19 | <td> | ||
20 | <a href="http://www.linuxtv.org/downloads/video4linux/API/V4L2_API">V4L2 API</a> | ||
21 | </td> | ||
22 | <td>Should be used for new projects | ||
23 | </td> | ||
24 | </tr> | ||
25 | </table> | ||
26 | </body> | ||
27 | </html> | ||
diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index 60ba66836038..0d93fa1ac25e 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv | |||
@@ -104,8 +104,8 @@ | |||
104 | 103 -> Grand X-Guard / Trust 814PCI [0304:0102] | 104 | 103 -> Grand X-Guard / Trust 814PCI [0304:0102] |
105 | 104 -> Nebula Electronics DigiTV [0071:0101] | 105 | 104 -> Nebula Electronics DigiTV [0071:0101] |
106 | 105 -> ProVideo PV143 [aa00:1430,aa00:1431,aa00:1432,aa00:1433,aa03:1433] | 106 | 105 -> ProVideo PV143 [aa00:1430,aa00:1431,aa00:1432,aa00:1433,aa03:1433] |
107 | 106 -> PHYTEC VD-009-X1 MiniDIN (bt878) | 107 | 106 -> PHYTEC VD-009-X1 VD-011 MiniDIN (bt878) |
108 | 107 -> PHYTEC VD-009-X1 Combi (bt878) | 108 | 107 -> PHYTEC VD-009-X1 VD-011 Combi (bt878) |
109 | 108 -> PHYTEC VD-009 MiniDIN (bt878) | 109 | 108 -> PHYTEC VD-009 MiniDIN (bt878) |
110 | 109 -> PHYTEC VD-009 Combi (bt878) | 110 | 109 -> PHYTEC VD-009 Combi (bt878) |
111 | 110 -> IVC-100 [ff00:a132] | 111 | 110 -> IVC-100 [ff00:a132] |
@@ -151,3 +151,6 @@ | |||
151 | 150 -> Geovision GV-600 [008a:763c] | 151 | 150 -> Geovision GV-600 [008a:763c] |
152 | 151 -> Kozumi KTV-01C | 152 | 151 -> Kozumi KTV-01C |
153 | 152 -> Encore ENL TV-FM-2 [1000:1801] | 153 | 152 -> Encore ENL TV-FM-2 [1000:1801] |
154 | 153 -> PHYTEC VD-012 (bt878) | ||
155 | 154 -> PHYTEC VD-012-X1 (bt878) | ||
156 | 155 -> PHYTEC VD-012-X2 (bt878) | ||
diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 64823ccacd69..35ea130e9898 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 | |||
@@ -11,3 +11,4 @@ | |||
11 | 10 -> DViCO FusionHDTV7 Dual Express [18ac:d618] | 11 | 10 -> DViCO FusionHDTV7 Dual Express [18ac:d618] |
12 | 11 -> DViCO FusionHDTV DVB-T Dual Express [18ac:db78] | 12 | 11 -> DViCO FusionHDTV DVB-T Dual Express [18ac:db78] |
13 | 12 -> Leadtek Winfast PxDVR3200 H [107d:6681] | 13 | 12 -> Leadtek Winfast PxDVR3200 H [107d:6681] |
14 | 13 -> Compro VideoMate E650F [185b:e800] | ||
diff --git a/Documentation/video4linux/CARDLIST.cx88 b/Documentation/video4linux/CARDLIST.cx88 index a5227e308f4a..0d08f1edcf6d 100644 --- a/Documentation/video4linux/CARDLIST.cx88 +++ b/Documentation/video4linux/CARDLIST.cx88 | |||
@@ -2,7 +2,7 @@ | |||
2 | 1 -> Hauppauge WinTV 34xxx models [0070:3400,0070:3401] | 2 | 1 -> Hauppauge WinTV 34xxx models [0070:3400,0070:3401] |
3 | 2 -> GDI Black Gold [14c7:0106,14c7:0107] | 3 | 2 -> GDI Black Gold [14c7:0106,14c7:0107] |
4 | 3 -> PixelView [1554:4811] | 4 | 3 -> PixelView [1554:4811] |
5 | 4 -> ATI TV Wonder Pro [1002:00f8] | 5 | 4 -> ATI TV Wonder Pro [1002:00f8,1002:00f9] |
6 | 5 -> Leadtek Winfast 2000XP Expert [107d:6611,107d:6613] | 6 | 5 -> Leadtek Winfast 2000XP Expert [107d:6611,107d:6613] |
7 | 6 -> AverTV Studio 303 (M126) [1461:000b] | 7 | 6 -> AverTV Studio 303 (M126) [1461:000b] |
8 | 7 -> MSI TV-@nywhere Master [1462:8606] | 8 | 7 -> MSI TV-@nywhere Master [1462:8606] |
@@ -74,3 +74,6 @@ | |||
74 | 73 -> TeVii S420 DVB-S [d420:9022] | 74 | 73 -> TeVii S420 DVB-S [d420:9022] |
75 | 74 -> Prolink Pixelview Global Extreme [1554:4976] | 75 | 74 -> Prolink Pixelview Global Extreme [1554:4976] |
76 | 75 -> PROF 7300 DVB-S/S2 [B033:3033] | 76 | 75 -> PROF 7300 DVB-S/S2 [B033:3033] |
77 | 76 -> SATTRADE ST4200 DVB-S/S2 [b200:4200] | ||
78 | 77 -> TBS 8910 DVB-S [8910:8888] | ||
79 | 78 -> Prof 6200 DVB-S [b022:3022] | ||
diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 187cc48d0924..75bded8a4aa2 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx | |||
@@ -1,5 +1,5 @@ | |||
1 | 0 -> Unknown EM2800 video grabber (em2800) [eb1a:2800] | 1 | 0 -> Unknown EM2800 video grabber (em2800) [eb1a:2800] |
2 | 1 -> Unknown EM2750/28xx video grabber (em2820/em2840) [eb1a:2820,eb1a:2860,eb1a:2861,eb1a:2870,eb1a:2881,eb1a:2883] | 2 | 1 -> Unknown EM2750/28xx video grabber (em2820/em2840) [eb1a:2820,eb1a:2821,eb1a:2860,eb1a:2861,eb1a:2870,eb1a:2881,eb1a:2883] |
3 | 2 -> Terratec Cinergy 250 USB (em2820/em2840) [0ccd:0036] | 3 | 2 -> Terratec Cinergy 250 USB (em2820/em2840) [0ccd:0036] |
4 | 3 -> Pinnacle PCTV USB 2 (em2820/em2840) [2304:0208] | 4 | 3 -> Pinnacle PCTV USB 2 (em2820/em2840) [2304:0208] |
5 | 4 -> Hauppauge WinTV USB 2 (em2820/em2840) [2040:4200,2040:4201] | 5 | 4 -> Hauppauge WinTV USB 2 (em2820/em2840) [2040:4200,2040:4201] |
@@ -12,9 +12,9 @@ | |||
12 | 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] | 12 | 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] |
13 | 12 -> Kworld PVR TV 2800 RF (em2820/em2840) | 13 | 12 -> Kworld PVR TV 2800 RF (em2820/em2840) |
14 | 13 -> Terratec Prodigy XS (em2880) [0ccd:0047] | 14 | 13 -> Terratec Prodigy XS (em2880) [0ccd:0047] |
15 | 14 -> Pixelview Prolink PlayTV USB 2.0 (em2820/em2840) [eb1a:2821] | 15 | 14 -> Pixelview Prolink PlayTV USB 2.0 (em2820/em2840) |
16 | 15 -> V-Gear PocketTV (em2800) | 16 | 15 -> V-Gear PocketTV (em2800) |
17 | 16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b,2040:651f] | 17 | 16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b] |
18 | 17 -> Pinnacle PCTV HD Pro Stick (em2880) [2304:0227] | 18 | 17 -> Pinnacle PCTV HD Pro Stick (em2880) [2304:0227] |
19 | 18 -> Hauppauge WinTV HVR 900 (R2) (em2880) [2040:6502] | 19 | 18 -> Hauppauge WinTV HVR 900 (R2) (em2880) [2040:6502] |
20 | 19 -> PointNix Intra-Oral Camera (em2860) | 20 | 19 -> PointNix Intra-Oral Camera (em2860) |
@@ -27,7 +27,6 @@ | |||
27 | 26 -> Hercules Smart TV USB 2.0 (em2820/em2840) | 27 | 26 -> Hercules Smart TV USB 2.0 (em2820/em2840) |
28 | 27 -> Pinnacle PCTV USB 2 (Philips FM1216ME) (em2820/em2840) | 28 | 27 -> Pinnacle PCTV USB 2 (Philips FM1216ME) (em2820/em2840) |
29 | 28 -> Leadtek Winfast USB II Deluxe (em2820/em2840) | 29 | 28 -> Leadtek Winfast USB II Deluxe (em2820/em2840) |
30 | 29 -> Pinnacle Dazzle DVC 100 (em2820/em2840) | ||
31 | 30 -> Videology 20K14XUSB USB2.0 (em2820/em2840) | 30 | 30 -> Videology 20K14XUSB USB2.0 (em2820/em2840) |
32 | 31 -> Usbgear VD204v9 (em2821) | 31 | 31 -> Usbgear VD204v9 (em2821) |
33 | 32 -> Supercomp USB 2.0 TV (em2821) | 32 | 32 -> Supercomp USB 2.0 TV (em2821) |
@@ -57,3 +56,5 @@ | |||
57 | 56 -> Pinnacle Hybrid Pro (2) (em2882) [2304:0226] | 56 | 56 -> Pinnacle Hybrid Pro (2) (em2882) [2304:0226] |
58 | 57 -> Kworld PlusTV HD Hybrid 330 (em2883) [eb1a:a316] | 57 | 57 -> Kworld PlusTV HD Hybrid 330 (em2883) [eb1a:a316] |
59 | 58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041] | 58 | 58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041] |
59 | 60 -> Hauppauge WinTV HVR 850 (em2883) [2040:651f] | ||
60 | 61 -> Pixelview PlayTV Box 4 USB 2.0 (em2820/em2840) | ||
diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index dc67eef38ff9..335aef4dcaeb 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 | |||
@@ -10,7 +10,7 @@ | |||
10 | 9 -> Medion 5044 | 10 | 9 -> Medion 5044 |
11 | 10 -> Kworld/KuroutoShikou SAA7130-TVPCI | 11 | 10 -> Kworld/KuroutoShikou SAA7130-TVPCI |
12 | 11 -> Terratec Cinergy 600 TV [153b:1143] | 12 | 11 -> Terratec Cinergy 600 TV [153b:1143] |
13 | 12 -> Medion 7134 [16be:0003] | 13 | 12 -> Medion 7134 [16be:0003,16be:5000] |
14 | 13 -> Typhoon TV+Radio 90031 | 14 | 13 -> Typhoon TV+Radio 90031 |
15 | 14 -> ELSA EX-VISION 300TV [1048:226b] | 15 | 14 -> ELSA EX-VISION 300TV [1048:226b] |
16 | 15 -> ELSA EX-VISION 500TV [1048:226a] | 16 | 15 -> ELSA EX-VISION 500TV [1048:226a] |
@@ -151,3 +151,4 @@ | |||
151 | 150 -> Zogis Real Angel 220 | 151 | 150 -> Zogis Real Angel 220 |
152 | 151 -> ADS Tech Instant HDTV [1421:0380] | 152 | 151 -> ADS Tech Instant HDTV [1421:0380] |
153 | 152 -> Asus Tiger Rev:1.00 [1043:4857] | 153 | 152 -> Asus Tiger Rev:1.00 [1043:4857] |
154 | 153 -> Kworld Plus TV Analog Lite PCI [17de:7128] | ||
diff --git a/Documentation/video4linux/README.cx88 b/Documentation/video4linux/README.cx88 index 166d5960b1a9..35fae23f883b 100644 --- a/Documentation/video4linux/README.cx88 +++ b/Documentation/video4linux/README.cx88 | |||
@@ -1,4 +1,3 @@ | |||
1 | |||
2 | cx8800 release notes | 1 | cx8800 release notes |
3 | ==================== | 2 | ==================== |
4 | 3 | ||
@@ -10,21 +9,20 @@ current status | |||
10 | 9 | ||
11 | video | 10 | video |
12 | - Basically works. | 11 | - Basically works. |
13 | - Some minor image quality glitches. | 12 | - For now, only capture and read(). Overlay isn't supported. |
14 | - For now only capture, overlay support isn't completed yet. | ||
15 | 13 | ||
16 | audio | 14 | audio |
17 | - The chip specs for the on-chip TV sound decoder are next | 15 | - The chip specs for the on-chip TV sound decoder are next |
18 | to useless :-/ | 16 | to useless :-/ |
19 | - Neverless the builtin TV sound decoder starts working now, | 17 | - Neverless the builtin TV sound decoder starts working now, |
20 | at least for PAL-BG. Other TV norms need other code ... | 18 | at least for some standards. |
21 | FOR ANY REPORTS ON THIS PLEASE MENTION THE TV NORM YOU ARE | 19 | FOR ANY REPORTS ON THIS PLEASE MENTION THE TV NORM YOU ARE |
22 | USING. | 20 | USING. |
23 | - Most tuner chips do provide mono sound, which may or may not | 21 | - Most tuner chips do provide mono sound, which may or may not |
24 | be useable depending on the board design. With the Hauppauge | 22 | be useable depending on the board design. With the Hauppauge |
25 | cards it works, so there is mono sound available as fallback. | 23 | cards it works, so there is mono sound available as fallback. |
26 | - audio data dma (i.e. recording without loopback cable to the | 24 | - audio data dma (i.e. recording without loopback cable to the |
27 | sound card) should be possible, but there is no code yet ... | 25 | sound card) is supported via cx88-alsa. |
28 | 26 | ||
29 | vbi | 27 | vbi |
30 | - Code present. Works for NTSC closed caption. PAL and other | 28 | - Code present. Works for NTSC closed caption. PAL and other |
diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 004818fab040..1c58a7630146 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt | |||
@@ -50,9 +50,14 @@ ov519 045e:028c Micro$oft xbox cam | |||
50 | spca508 0461:0815 Micro Innovation IC200 | 50 | spca508 0461:0815 Micro Innovation IC200 |
51 | sunplus 0461:0821 Fujifilm MV-1 | 51 | sunplus 0461:0821 Fujifilm MV-1 |
52 | zc3xx 0461:0a00 MicroInnovation WebCam320 | 52 | zc3xx 0461:0a00 MicroInnovation WebCam320 |
53 | stv06xx 046d:0840 QuickCam Express | ||
54 | stv06xx 046d:0850 LEGO cam / QuickCam Web | ||
55 | stv06xx 046d:0870 Dexxa WebCam USB | ||
53 | spca500 046d:0890 Logitech QuickCam traveler | 56 | spca500 046d:0890 Logitech QuickCam traveler |
54 | vc032x 046d:0892 Logitech Orbicam | 57 | vc032x 046d:0892 Logitech Orbicam |
55 | vc032x 046d:0896 Logitech Orbicam | 58 | vc032x 046d:0896 Logitech Orbicam |
59 | vc032x 046d:0897 Logitech QuickCam for Dell notebooks | ||
60 | zc3xx 046d:089d Logitech QuickCam E2500 | ||
56 | zc3xx 046d:08a0 Logitech QC IM | 61 | zc3xx 046d:08a0 Logitech QC IM |
57 | zc3xx 046d:08a1 Logitech QC IM 0x08A1 +sound | 62 | zc3xx 046d:08a1 Logitech QC IM 0x08A1 +sound |
58 | zc3xx 046d:08a2 Labtec Webcam Pro | 63 | zc3xx 046d:08a2 Labtec Webcam Pro |
@@ -169,6 +174,9 @@ spca500 06bd:0404 Agfa CL20 | |||
169 | spca500 06be:0800 Optimedia | 174 | spca500 06be:0800 Optimedia |
170 | sunplus 06d6:0031 Trust 610 LCD PowerC@m Zoom | 175 | sunplus 06d6:0031 Trust 610 LCD PowerC@m Zoom |
171 | spca506 06e1:a190 ADS Instant VCD | 176 | spca506 06e1:a190 ADS Instant VCD |
177 | ov534 06f8:3002 Hercules Blog Webcam | ||
178 | ov534 06f8:3003 Hercules Dualpix HD Weblog | ||
179 | sonixj 06f8:3004 Hercules Classic Silver | ||
172 | spca508 0733:0110 ViewQuest VQ110 | 180 | spca508 0733:0110 ViewQuest VQ110 |
173 | spca508 0130:0130 Clone Digital Webcam 11043 | 181 | spca508 0130:0130 Clone Digital Webcam 11043 |
174 | spca501 0733:0401 Intel Create and Share | 182 | spca501 0733:0401 Intel Create and Share |
@@ -199,7 +207,8 @@ sunplus 08ca:2050 Medion MD 41437 | |||
199 | sunplus 08ca:2060 Aiptek PocketDV5300 | 207 | sunplus 08ca:2060 Aiptek PocketDV5300 |
200 | tv8532 0923:010f ICM532 cams | 208 | tv8532 0923:010f ICM532 cams |
201 | mars 093a:050f Mars-Semi Pc-Camera | 209 | mars 093a:050f Mars-Semi Pc-Camera |
202 | pac207 093a:2460 PAC207 Qtec Webcam 100 | 210 | pac207 093a:2460 Qtec Webcam 100 |
211 | pac207 093a:2461 HP Webcam | ||
203 | pac207 093a:2463 Philips SPC 220 NC | 212 | pac207 093a:2463 Philips SPC 220 NC |
204 | pac207 093a:2464 Labtec Webcam 1200 | 213 | pac207 093a:2464 Labtec Webcam 1200 |
205 | pac207 093a:2468 PAC207 | 214 | pac207 093a:2468 PAC207 |
@@ -213,10 +222,13 @@ pac7311 093a:2603 PAC7312 | |||
213 | pac7311 093a:2608 Trust WB-3300p | 222 | pac7311 093a:2608 Trust WB-3300p |
214 | pac7311 093a:260e Gigaware VGA PC Camera, Trust WB-3350p, SIGMA cam 2350 | 223 | pac7311 093a:260e Gigaware VGA PC Camera, Trust WB-3350p, SIGMA cam 2350 |
215 | pac7311 093a:260f SnakeCam | 224 | pac7311 093a:260f SnakeCam |
225 | pac7311 093a:2620 Apollo AC-905 | ||
216 | pac7311 093a:2621 PAC731x | 226 | pac7311 093a:2621 PAC731x |
227 | pac7311 093a:2622 Genius Eye 312 | ||
217 | pac7311 093a:2624 PAC7302 | 228 | pac7311 093a:2624 PAC7302 |
218 | pac7311 093a:2626 Labtec 2200 | 229 | pac7311 093a:2626 Labtec 2200 |
219 | pac7311 093a:262a Webcam 300k | 230 | pac7311 093a:262a Webcam 300k |
231 | pac7311 093a:262c Philips SPC 230 NC | ||
220 | zc3xx 0ac8:0302 Z-star Vimicro zc0302 | 232 | zc3xx 0ac8:0302 Z-star Vimicro zc0302 |
221 | vc032x 0ac8:0321 Vimicro generic vc0321 | 233 | vc032x 0ac8:0321 Vimicro generic vc0321 |
222 | vc032x 0ac8:0323 Vimicro Vc0323 | 234 | vc032x 0ac8:0323 Vimicro Vc0323 |
@@ -249,11 +261,13 @@ sonixj 0c45:60c0 Sangha Sn535 | |||
249 | sonixj 0c45:60ec SN9C105+MO4000 | 261 | sonixj 0c45:60ec SN9C105+MO4000 |
250 | sonixj 0c45:60fb Surfer NoName | 262 | sonixj 0c45:60fb Surfer NoName |
251 | sonixj 0c45:60fc LG-LIC300 | 263 | sonixj 0c45:60fc LG-LIC300 |
264 | sonixj 0c45:60fe Microdia Audio | ||
252 | sonixj 0c45:6128 Microdia/Sonix SNP325 | 265 | sonixj 0c45:6128 Microdia/Sonix SNP325 |
253 | sonixj 0c45:612a Avant Camera | 266 | sonixj 0c45:612a Avant Camera |
254 | sonixj 0c45:612c Typhoon Rasy Cam 1.3MPix | 267 | sonixj 0c45:612c Typhoon Rasy Cam 1.3MPix |
255 | sonixj 0c45:6130 Sonix Pccam | 268 | sonixj 0c45:6130 Sonix Pccam |
256 | sonixj 0c45:6138 Sn9c120 Mo4000 | 269 | sonixj 0c45:6138 Sn9c120 Mo4000 |
270 | sonixj 0c45:613a Microdia Sonix PC Camera | ||
257 | sonixj 0c45:613b Surfer SN-206 | 271 | sonixj 0c45:613b Surfer SN-206 |
258 | sonixj 0c45:613c Sonix Pccam168 | 272 | sonixj 0c45:613c Sonix Pccam168 |
259 | sonixj 0c45:6143 Sonix Pccam168 | 273 | sonixj 0c45:6143 Sonix Pccam168 |
@@ -263,6 +277,9 @@ etoms 102c:6251 Qcam xxxxxx VGA | |||
263 | zc3xx 10fd:0128 Typhoon Webshot II USB 300k 0x0128 | 277 | zc3xx 10fd:0128 Typhoon Webshot II USB 300k 0x0128 |
264 | spca561 10fd:7e50 FlyCam Usb 100 | 278 | spca561 10fd:7e50 FlyCam Usb 100 |
265 | zc3xx 10fd:8050 Typhoon Webshot II USB 300k | 279 | zc3xx 10fd:8050 Typhoon Webshot II USB 300k |
280 | ov534 1415:2000 Sony HD Eye for PS3 (SLEH 00201) | ||
281 | pac207 145f:013a Trust WB-1300N | ||
282 | vc032x 15b8:6002 HP 2.0 Megapixel rz406aa | ||
266 | spca501 1776:501c Arowana 300K CMOS Camera | 283 | spca501 1776:501c Arowana 300K CMOS Camera |
267 | t613 17a1:0128 TASCORP JPEG Webcam, NGS Cyclops | 284 | t613 17a1:0128 TASCORP JPEG Webcam, NGS Cyclops |
268 | vc032x 17ef:4802 Lenovo Vc0323+MI1310_SOC | 285 | vc032x 17ef:4802 Lenovo Vc0323+MI1310_SOC |
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt new file mode 100644 index 000000000000..eeae76c22a93 --- /dev/null +++ b/Documentation/video4linux/v4l2-framework.txt | |||
@@ -0,0 +1,520 @@ | |||
1 | Overview of the V4L2 driver framework | ||
2 | ===================================== | ||
3 | |||
4 | This text documents the various structures provided by the V4L2 framework and | ||
5 | their relationships. | ||
6 | |||
7 | |||
8 | Introduction | ||
9 | ------------ | ||
10 | |||
11 | The V4L2 drivers tend to be very complex due to the complexity of the | ||
12 | hardware: most devices have multiple ICs, export multiple device nodes in | ||
13 | /dev, and create also non-V4L2 devices such as DVB, ALSA, FB, I2C and input | ||
14 | (IR) devices. | ||
15 | |||
16 | Especially the fact that V4L2 drivers have to setup supporting ICs to | ||
17 | do audio/video muxing/encoding/decoding makes it more complex than most. | ||
18 | Usually these ICs are connected to the main bridge driver through one or | ||
19 | more I2C busses, but other busses can also be used. Such devices are | ||
20 | called 'sub-devices'. | ||
21 | |||
22 | For a long time the framework was limited to the video_device struct for | ||
23 | creating V4L device nodes and video_buf for handling the video buffers | ||
24 | (note that this document does not discuss the video_buf framework). | ||
25 | |||
26 | This meant that all drivers had to do the setup of device instances and | ||
27 | connecting to sub-devices themselves. Some of this is quite complicated | ||
28 | to do right and many drivers never did do it correctly. | ||
29 | |||
30 | There is also a lot of common code that could never be refactored due to | ||
31 | the lack of a framework. | ||
32 | |||
33 | So this framework sets up the basic building blocks that all drivers | ||
34 | need and this same framework should make it much easier to refactor | ||
35 | common code into utility functions shared by all drivers. | ||
36 | |||
37 | |||
38 | Structure of a driver | ||
39 | --------------------- | ||
40 | |||
41 | All drivers have the following structure: | ||
42 | |||
43 | 1) A struct for each device instance containing the device state. | ||
44 | |||
45 | 2) A way of initializing and commanding sub-devices (if any). | ||
46 | |||
47 | 3) Creating V4L2 device nodes (/dev/videoX, /dev/vbiX, /dev/radioX and | ||
48 | /dev/vtxX) and keeping track of device-node specific data. | ||
49 | |||
50 | 4) Filehandle-specific structs containing per-filehandle data. | ||
51 | |||
52 | This is a rough schematic of how it all relates: | ||
53 | |||
54 | device instances | ||
55 | | | ||
56 | +-sub-device instances | ||
57 | | | ||
58 | \-V4L2 device nodes | ||
59 | | | ||
60 | \-filehandle instances | ||
61 | |||
62 | |||
63 | Structure of the framework | ||
64 | -------------------------- | ||
65 | |||
66 | The framework closely resembles the driver structure: it has a v4l2_device | ||
67 | struct for the device instance data, a v4l2_subdev struct to refer to | ||
68 | sub-device instances, the video_device struct stores V4L2 device node data | ||
69 | and in the future a v4l2_fh struct will keep track of filehandle instances | ||
70 | (this is not yet implemented). | ||
71 | |||
72 | |||
73 | struct v4l2_device | ||
74 | ------------------ | ||
75 | |||
76 | Each device instance is represented by a struct v4l2_device (v4l2-device.h). | ||
77 | Very simple devices can just allocate this struct, but most of the time you | ||
78 | would embed this struct inside a larger struct. | ||
79 | |||
80 | You must register the device instance: | ||
81 | |||
82 | v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev); | ||
83 | |||
84 | Registration will initialize the v4l2_device struct and link dev->driver_data | ||
85 | to v4l2_dev. Registration will also set v4l2_dev->name to a value derived from | ||
86 | dev (driver name followed by the bus_id, to be precise). You may change the | ||
87 | name after registration if you want. | ||
88 | |||
89 | The first 'dev' argument is normally the struct device pointer of a pci_dev, | ||
90 | usb_device or platform_device. | ||
91 | |||
92 | You unregister with: | ||
93 | |||
94 | v4l2_device_unregister(struct v4l2_device *v4l2_dev); | ||
95 | |||
96 | Unregistering will also automatically unregister all subdevs from the device. | ||
97 | |||
98 | Sometimes you need to iterate over all devices registered by a specific | ||
99 | driver. This is usually the case if multiple device drivers use the same | ||
100 | hardware. E.g. the ivtvfb driver is a framebuffer driver that uses the ivtv | ||
101 | hardware. The same is true for alsa drivers for example. | ||
102 | |||
103 | You can iterate over all registered devices as follows: | ||
104 | |||
105 | static int callback(struct device *dev, void *p) | ||
106 | { | ||
107 | struct v4l2_device *v4l2_dev = dev_get_drvdata(dev); | ||
108 | |||
109 | /* test if this device was inited */ | ||
110 | if (v4l2_dev == NULL) | ||
111 | return 0; | ||
112 | ... | ||
113 | return 0; | ||
114 | } | ||
115 | |||
116 | int iterate(void *p) | ||
117 | { | ||
118 | struct device_driver *drv; | ||
119 | int err; | ||
120 | |||
121 | /* Find driver 'ivtv' on the PCI bus. | ||
122 | pci_bus_type is a global. For USB busses use usb_bus_type. */ | ||
123 | drv = driver_find("ivtv", &pci_bus_type); | ||
124 | /* iterate over all ivtv device instances */ | ||
125 | err = driver_for_each_device(drv, NULL, p, callback); | ||
126 | put_driver(drv); | ||
127 | return err; | ||
128 | } | ||
129 | |||
130 | Sometimes you need to keep a running counter of the device instance. This is | ||
131 | commonly used to map a device instance to an index of a module option array. | ||
132 | |||
133 | The recommended approach is as follows: | ||
134 | |||
135 | static atomic_t drv_instance = ATOMIC_INIT(0); | ||
136 | |||
137 | static int __devinit drv_probe(struct pci_dev *dev, | ||
138 | const struct pci_device_id *pci_id) | ||
139 | { | ||
140 | ... | ||
141 | state->instance = atomic_inc_return(&drv_instance) - 1; | ||
142 | } | ||
143 | |||
144 | |||
145 | struct v4l2_subdev | ||
146 | ------------------ | ||
147 | |||
148 | Many drivers need to communicate with sub-devices. These devices can do all | ||
149 | sort of tasks, but most commonly they handle audio and/or video muxing, | ||
150 | encoding or decoding. For webcams common sub-devices are sensors and camera | ||
151 | controllers. | ||
152 | |||
153 | Usually these are I2C devices, but not necessarily. In order to provide the | ||
154 | driver with a consistent interface to these sub-devices the v4l2_subdev struct | ||
155 | (v4l2-subdev.h) was created. | ||
156 | |||
157 | Each sub-device driver must have a v4l2_subdev struct. This struct can be | ||
158 | stand-alone for simple sub-devices or it might be embedded in a larger struct | ||
159 | if more state information needs to be stored. Usually there is a low-level | ||
160 | device struct (e.g. i2c_client) that contains the device data as setup | ||
161 | by the kernel. It is recommended to store that pointer in the private | ||
162 | data of v4l2_subdev using v4l2_set_subdevdata(). That makes it easy to go | ||
163 | from a v4l2_subdev to the actual low-level bus-specific device data. | ||
164 | |||
165 | You also need a way to go from the low-level struct to v4l2_subdev. For the | ||
166 | common i2c_client struct the i2c_set_clientdata() call is used to store a | ||
167 | v4l2_subdev pointer, for other busses you may have to use other methods. | ||
168 | |||
169 | From the bridge driver perspective you load the sub-device module and somehow | ||
170 | obtain the v4l2_subdev pointer. For i2c devices this is easy: you call | ||
171 | i2c_get_clientdata(). For other busses something similar needs to be done. | ||
172 | Helper functions exists for sub-devices on an I2C bus that do most of this | ||
173 | tricky work for you. | ||
174 | |||
175 | Each v4l2_subdev contains function pointers that sub-device drivers can | ||
176 | implement (or leave NULL if it is not applicable). Since sub-devices can do | ||
177 | so many different things and you do not want to end up with a huge ops struct | ||
178 | of which only a handful of ops are commonly implemented, the function pointers | ||
179 | are sorted according to category and each category has its own ops struct. | ||
180 | |||
181 | The top-level ops struct contains pointers to the category ops structs, which | ||
182 | may be NULL if the subdev driver does not support anything from that category. | ||
183 | |||
184 | It looks like this: | ||
185 | |||
186 | struct v4l2_subdev_core_ops { | ||
187 | int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_chip_ident *chip); | ||
188 | int (*log_status)(struct v4l2_subdev *sd); | ||
189 | int (*init)(struct v4l2_subdev *sd, u32 val); | ||
190 | ... | ||
191 | }; | ||
192 | |||
193 | struct v4l2_subdev_tuner_ops { | ||
194 | ... | ||
195 | }; | ||
196 | |||
197 | struct v4l2_subdev_audio_ops { | ||
198 | ... | ||
199 | }; | ||
200 | |||
201 | struct v4l2_subdev_video_ops { | ||
202 | ... | ||
203 | }; | ||
204 | |||
205 | struct v4l2_subdev_ops { | ||
206 | const struct v4l2_subdev_core_ops *core; | ||
207 | const struct v4l2_subdev_tuner_ops *tuner; | ||
208 | const struct v4l2_subdev_audio_ops *audio; | ||
209 | const struct v4l2_subdev_video_ops *video; | ||
210 | }; | ||
211 | |||
212 | The core ops are common to all subdevs, the other categories are implemented | ||
213 | depending on the sub-device. E.g. a video device is unlikely to support the | ||
214 | audio ops and vice versa. | ||
215 | |||
216 | This setup limits the number of function pointers while still making it easy | ||
217 | to add new ops and categories. | ||
218 | |||
219 | A sub-device driver initializes the v4l2_subdev struct using: | ||
220 | |||
221 | v4l2_subdev_init(subdev, &ops); | ||
222 | |||
223 | Afterwards you need to initialize subdev->name with a unique name and set the | ||
224 | module owner. This is done for you if you use the i2c helper functions. | ||
225 | |||
226 | A device (bridge) driver needs to register the v4l2_subdev with the | ||
227 | v4l2_device: | ||
228 | |||
229 | int err = v4l2_device_register_subdev(device, subdev); | ||
230 | |||
231 | This can fail if the subdev module disappeared before it could be registered. | ||
232 | After this function was called successfully the subdev->dev field points to | ||
233 | the v4l2_device. | ||
234 | |||
235 | You can unregister a sub-device using: | ||
236 | |||
237 | v4l2_device_unregister_subdev(subdev); | ||
238 | |||
239 | Afterwards the subdev module can be unloaded and subdev->dev == NULL. | ||
240 | |||
241 | You can call an ops function either directly: | ||
242 | |||
243 | err = subdev->ops->core->g_chip_ident(subdev, &chip); | ||
244 | |||
245 | but it is better and easier to use this macro: | ||
246 | |||
247 | err = v4l2_subdev_call(subdev, core, g_chip_ident, &chip); | ||
248 | |||
249 | The macro will to the right NULL pointer checks and returns -ENODEV if subdev | ||
250 | is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_chip_ident is | ||
251 | NULL, or the actual result of the subdev->ops->core->g_chip_ident ops. | ||
252 | |||
253 | It is also possible to call all or a subset of the sub-devices: | ||
254 | |||
255 | v4l2_device_call_all(dev, 0, core, g_chip_ident, &chip); | ||
256 | |||
257 | Any subdev that does not support this ops is skipped and error results are | ||
258 | ignored. If you want to check for errors use this: | ||
259 | |||
260 | err = v4l2_device_call_until_err(dev, 0, core, g_chip_ident, &chip); | ||
261 | |||
262 | Any error except -ENOIOCTLCMD will exit the loop with that error. If no | ||
263 | errors (except -ENOIOCTLCMD) occured, then 0 is returned. | ||
264 | |||
265 | The second argument to both calls is a group ID. If 0, then all subdevs are | ||
266 | called. If non-zero, then only those whose group ID match that value will | ||
267 | be called. Before a bridge driver registers a subdev it can set subdev->grp_id | ||
268 | to whatever value it wants (it's 0 by default). This value is owned by the | ||
269 | bridge driver and the sub-device driver will never modify or use it. | ||
270 | |||
271 | The group ID gives the bridge driver more control how callbacks are called. | ||
272 | For example, there may be multiple audio chips on a board, each capable of | ||
273 | changing the volume. But usually only one will actually be used when the | ||
274 | user want to change the volume. You can set the group ID for that subdev to | ||
275 | e.g. AUDIO_CONTROLLER and specify that as the group ID value when calling | ||
276 | v4l2_device_call_all(). That ensures that it will only go to the subdev | ||
277 | that needs it. | ||
278 | |||
279 | The advantage of using v4l2_subdev is that it is a generic struct and does | ||
280 | not contain any knowledge about the underlying hardware. So a driver might | ||
281 | contain several subdevs that use an I2C bus, but also a subdev that is | ||
282 | controlled through GPIO pins. This distinction is only relevant when setting | ||
283 | up the device, but once the subdev is registered it is completely transparent. | ||
284 | |||
285 | |||
286 | I2C sub-device drivers | ||
287 | ---------------------- | ||
288 | |||
289 | Since these drivers are so common, special helper functions are available to | ||
290 | ease the use of these drivers (v4l2-common.h). | ||
291 | |||
292 | The recommended method of adding v4l2_subdev support to an I2C driver is to | ||
293 | embed the v4l2_subdev struct into the state struct that is created for each | ||
294 | I2C device instance. Very simple devices have no state struct and in that case | ||
295 | you can just create a v4l2_subdev directly. | ||
296 | |||
297 | A typical state struct would look like this (where 'chipname' is replaced by | ||
298 | the name of the chip): | ||
299 | |||
300 | struct chipname_state { | ||
301 | struct v4l2_subdev sd; | ||
302 | ... /* additional state fields */ | ||
303 | }; | ||
304 | |||
305 | Initialize the v4l2_subdev struct as follows: | ||
306 | |||
307 | v4l2_i2c_subdev_init(&state->sd, client, subdev_ops); | ||
308 | |||
309 | This function will fill in all the fields of v4l2_subdev and ensure that the | ||
310 | v4l2_subdev and i2c_client both point to one another. | ||
311 | |||
312 | You should also add a helper inline function to go from a v4l2_subdev pointer | ||
313 | to a chipname_state struct: | ||
314 | |||
315 | static inline struct chipname_state *to_state(struct v4l2_subdev *sd) | ||
316 | { | ||
317 | return container_of(sd, struct chipname_state, sd); | ||
318 | } | ||
319 | |||
320 | Use this to go from the v4l2_subdev struct to the i2c_client struct: | ||
321 | |||
322 | struct i2c_client *client = v4l2_get_subdevdata(sd); | ||
323 | |||
324 | And this to go from an i2c_client to a v4l2_subdev struct: | ||
325 | |||
326 | struct v4l2_subdev *sd = i2c_get_clientdata(client); | ||
327 | |||
328 | Finally you need to make a command function to make driver->command() | ||
329 | call the right subdev_ops functions: | ||
330 | |||
331 | static int subdev_command(struct i2c_client *client, unsigned cmd, void *arg) | ||
332 | { | ||
333 | return v4l2_subdev_command(i2c_get_clientdata(client), cmd, arg); | ||
334 | } | ||
335 | |||
336 | If driver->command is never used then you can leave this out. Eventually the | ||
337 | driver->command usage should be removed from v4l. | ||
338 | |||
339 | Make sure to call v4l2_device_unregister_subdev(sd) when the remove() callback | ||
340 | is called. This will unregister the sub-device from the bridge driver. It is | ||
341 | safe to call this even if the sub-device was never registered. | ||
342 | |||
343 | |||
344 | The bridge driver also has some helper functions it can use: | ||
345 | |||
346 | struct v4l2_subdev *sd = v4l2_i2c_new_subdev(adapter, "module_foo", "chipid", 0x36); | ||
347 | |||
348 | This loads the given module (can be NULL if no module needs to be loaded) and | ||
349 | calls i2c_new_device() with the given i2c_adapter and chip/address arguments. | ||
350 | If all goes well, then it registers the subdev with the v4l2_device. It gets | ||
351 | the v4l2_device by calling i2c_get_adapdata(adapter), so you should make sure | ||
352 | that adapdata is set to v4l2_device when you setup the i2c_adapter in your | ||
353 | driver. | ||
354 | |||
355 | You can also use v4l2_i2c_new_probed_subdev() which is very similar to | ||
356 | v4l2_i2c_new_subdev(), except that it has an array of possible I2C addresses | ||
357 | that it should probe. Internally it calls i2c_new_probed_device(). | ||
358 | |||
359 | Both functions return NULL if something went wrong. | ||
360 | |||
361 | |||
362 | struct video_device | ||
363 | ------------------- | ||
364 | |||
365 | The actual device nodes in the /dev directory are created using the | ||
366 | video_device struct (v4l2-dev.h). This struct can either be allocated | ||
367 | dynamically or embedded in a larger struct. | ||
368 | |||
369 | To allocate it dynamically use: | ||
370 | |||
371 | struct video_device *vdev = video_device_alloc(); | ||
372 | |||
373 | if (vdev == NULL) | ||
374 | return -ENOMEM; | ||
375 | |||
376 | vdev->release = video_device_release; | ||
377 | |||
378 | If you embed it in a larger struct, then you must set the release() | ||
379 | callback to your own function: | ||
380 | |||
381 | struct video_device *vdev = &my_vdev->vdev; | ||
382 | |||
383 | vdev->release = my_vdev_release; | ||
384 | |||
385 | The release callback must be set and it is called when the last user | ||
386 | of the video device exits. | ||
387 | |||
388 | The default video_device_release() callback just calls kfree to free the | ||
389 | allocated memory. | ||
390 | |||
391 | You should also set these fields: | ||
392 | |||
393 | - parent: set to the parent device (same device as was used to register | ||
394 | v4l2_device). | ||
395 | - name: set to something descriptive and unique. | ||
396 | - fops: set to the file_operations struct. | ||
397 | - ioctl_ops: if you use the v4l2_ioctl_ops to simplify ioctl maintenance | ||
398 | (highly recommended to use this and it might become compulsory in the | ||
399 | future!), then set this to your v4l2_ioctl_ops struct. | ||
400 | |||
401 | If you use v4l2_ioctl_ops, then you should set .unlocked_ioctl to | ||
402 | __video_ioctl2 or .ioctl to video_ioctl2 in your file_operations struct. | ||
403 | |||
404 | |||
405 | video_device registration | ||
406 | ------------------------- | ||
407 | |||
408 | Next you register the video device: this will create the character device | ||
409 | for you. | ||
410 | |||
411 | err = video_register_device(vdev, VFL_TYPE_GRABBER, -1); | ||
412 | if (err) { | ||
413 | video_device_release(vdev); // or kfree(my_vdev); | ||
414 | return err; | ||
415 | } | ||
416 | |||
417 | Which device is registered depends on the type argument. The following | ||
418 | types exist: | ||
419 | |||
420 | VFL_TYPE_GRABBER: videoX for video input/output devices | ||
421 | VFL_TYPE_VBI: vbiX for vertical blank data (i.e. closed captions, teletext) | ||
422 | VFL_TYPE_RADIO: radioX for radio tuners | ||
423 | VFL_TYPE_VTX: vtxX for teletext devices (deprecated, don't use) | ||
424 | |||
425 | The last argument gives you a certain amount of control over the device | ||
426 | kernel number used (i.e. the X in videoX). Normally you will pass -1 to | ||
427 | let the v4l2 framework pick the first free number. But if a driver creates | ||
428 | many devices, then it can be useful to have different video devices in | ||
429 | separate ranges. For example, video capture devices start at 0, video | ||
430 | output devices start at 16. | ||
431 | |||
432 | So you can use the last argument to specify a minimum kernel number and | ||
433 | the v4l2 framework will try to pick the first free number that is equal | ||
434 | or higher to what you passed. If that fails, then it will just pick the | ||
435 | first free number. | ||
436 | |||
437 | Whenever a device node is created some attributes are also created for you. | ||
438 | If you look in /sys/class/video4linux you see the devices. Go into e.g. | ||
439 | video0 and you will see 'name' and 'index' attributes. The 'name' attribute | ||
440 | is the 'name' field of the video_device struct. The 'index' attribute is | ||
441 | a device node index that can be assigned by the driver, or that is calculated | ||
442 | for you. | ||
443 | |||
444 | If you call video_register_device(), then the index is just increased by | ||
445 | 1 for each device node you register. The first video device node you register | ||
446 | always starts off with 0. | ||
447 | |||
448 | Alternatively you can call video_register_device_index() which is identical | ||
449 | to video_register_device(), but with an extra index argument. Here you can | ||
450 | pass a specific index value (between 0 and 31) that should be used. | ||
451 | |||
452 | Users can setup udev rules that utilize the index attribute to make fancy | ||
453 | device names (e.g. 'mpegX' for MPEG video capture device nodes). | ||
454 | |||
455 | After the device was successfully registered, then you can use these fields: | ||
456 | |||
457 | - vfl_type: the device type passed to video_register_device. | ||
458 | - minor: the assigned device minor number. | ||
459 | - num: the device kernel number (i.e. the X in videoX). | ||
460 | - index: the device index number (calculated or set explicitly using | ||
461 | video_register_device_index). | ||
462 | |||
463 | If the registration failed, then you need to call video_device_release() | ||
464 | to free the allocated video_device struct, or free your own struct if the | ||
465 | video_device was embedded in it. The vdev->release() callback will never | ||
466 | be called if the registration failed, nor should you ever attempt to | ||
467 | unregister the device if the registration failed. | ||
468 | |||
469 | |||
470 | video_device cleanup | ||
471 | -------------------- | ||
472 | |||
473 | When the video device nodes have to be removed, either during the unload | ||
474 | of the driver or because the USB device was disconnected, then you should | ||
475 | unregister them: | ||
476 | |||
477 | video_unregister_device(vdev); | ||
478 | |||
479 | This will remove the device nodes from sysfs (causing udev to remove them | ||
480 | from /dev). | ||
481 | |||
482 | After video_unregister_device() returns no new opens can be done. | ||
483 | |||
484 | However, in the case of USB devices some application might still have one | ||
485 | of these device nodes open. You should block all new accesses to read, | ||
486 | write, poll, etc. except possibly for certain ioctl operations like | ||
487 | queueing buffers. | ||
488 | |||
489 | When the last user of the video device node exits, then the vdev->release() | ||
490 | callback is called and you can do the final cleanup there. | ||
491 | |||
492 | |||
493 | video_device helper functions | ||
494 | ----------------------------- | ||
495 | |||
496 | There are a few useful helper functions: | ||
497 | |||
498 | You can set/get driver private data in the video_device struct using: | ||
499 | |||
500 | void *video_get_drvdata(struct video_device *dev); | ||
501 | void video_set_drvdata(struct video_device *dev, void *data); | ||
502 | |||
503 | Note that you can safely call video_set_drvdata() before calling | ||
504 | video_register_device(). | ||
505 | |||
506 | And this function: | ||
507 | |||
508 | struct video_device *video_devdata(struct file *file); | ||
509 | |||
510 | returns the video_device belonging to the file struct. | ||
511 | |||
512 | The final helper function combines video_get_drvdata with | ||
513 | video_devdata: | ||
514 | |||
515 | void *video_drvdata(struct file *file); | ||
516 | |||
517 | You can go from a video_device struct to the v4l2_device struct using: | ||
518 | |||
519 | struct v4l2_device *v4l2_dev = dev_get_drvdata(vdev->parent); | ||
520 | |||