diff options
Diffstat (limited to 'Documentation/video4linux/v4l2-framework.txt')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index ba4706afc5fb..e395a9cdc533 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -370,19 +370,20 @@ from the remove() callback ensures that this is always done correctly. The bridge driver also has some helper functions it can use: struct v4l2_subdev *sd = v4l2_i2c_new_subdev(v4l2_dev, adapter, - "module_foo", "chipid", 0x36); + "module_foo", "chipid", 0x36, NULL); This loads the given module (can be NULL if no module needs to be loaded) and calls i2c_new_device() with the given i2c_adapter and chip/address arguments. If all goes well, then it registers the subdev with the v4l2_device. -You can also use v4l2_i2c_new_probed_subdev() which is very similar to -v4l2_i2c_new_subdev(), except that it has an array of possible I2C addresses -that it should probe. Internally it calls i2c_new_probed_device(). +You can also use the last argument of v4l2_i2c_new_subdev() to pass an array +of possible I2C addresses that it should probe. These probe addresses are +only used if the previous argument is 0. A non-zero argument means that you +know the exact i2c address so in that case no probing will take place. Both functions return NULL if something went wrong. -Note that the chipid you pass to v4l2_i2c_new_(probed_)subdev() is usually +Note that the chipid you pass to v4l2_i2c_new_subdev() is usually the same as the module name. It allows you to specify a chip variant, e.g. "saa7114" or "saa7115". In general though the i2c driver autodetects this. The use of chipid is something that needs to be looked at more closely at a @@ -410,11 +411,6 @@ the irq and platform_data arguments after the subdev was setup. The older v4l2_i2c_new_(probed_)subdev functions will call s_config as well, but with irq set to 0 and platform_data set to NULL. -Note that in the next kernel release the functions v4l2_i2c_new_subdev, -v4l2_i2c_new_probed_subdev and v4l2_i2c_new_probed_subdev_addr will all be -replaced by a single v4l2_i2c_new_subdev that is identical to -v4l2_i2c_new_subdev_cfg but without the irq and platform_data arguments. - struct video_device ------------------- |