diff options
Diffstat (limited to 'Documentation/video4linux')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index e831aaca66f8..f5fdb395287f 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt | |||
| @@ -192,6 +192,11 @@ You also need a way to go from the low-level struct to v4l2_subdev. For the | |||
| 192 | common i2c_client struct the i2c_set_clientdata() call is used to store a | 192 | common i2c_client struct the i2c_set_clientdata() call is used to store a |
| 193 | v4l2_subdev pointer, for other busses you may have to use other methods. | 193 | v4l2_subdev pointer, for other busses you may have to use other methods. |
| 194 | 194 | ||
| 195 | Bridges might also need to store per-subdev private data, such as a pointer to | ||
| 196 | bridge-specific per-subdev private data. The v4l2_subdev structure provides | ||
| 197 | host private data for that purpose that can be accessed with | ||
| 198 | v4l2_get_subdev_hostdata() and v4l2_set_subdev_hostdata(). | ||
| 199 | |||
| 195 | From the bridge driver perspective you load the sub-device module and somehow | 200 | From the bridge driver perspective you load the sub-device module and somehow |
| 196 | obtain the v4l2_subdev pointer. For i2c devices this is easy: you call | 201 | obtain the v4l2_subdev pointer. For i2c devices this is easy: you call |
| 197 | i2c_get_clientdata(). For other busses something similar needs to be done. | 202 | i2c_get_clientdata(). For other busses something similar needs to be done. |