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-rw-r--r--Documentation/video4linux/v4l2-framework.txt21
1 files changed, 4 insertions, 17 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt
index a31177390e55..854808b67fae 100644
--- a/Documentation/video4linux/v4l2-framework.txt
+++ b/Documentation/video4linux/v4l2-framework.txt
@@ -90,7 +90,7 @@ up before calling v4l2_device_register then it will be untouched. If dev is
NULL, then you *must* setup v4l2_dev->name before calling v4l2_device_register.
The first 'dev' argument is normally the struct device pointer of a pci_dev,
-usb_device or platform_device. It is rare for dev to be NULL, but it happens
+usb_interface or platform_device. It is rare for dev to be NULL, but it happens
with ISA devices or when one device creates multiple PCI devices, thus making
it impossible to associate v4l2_dev with a particular parent.
@@ -351,17 +351,6 @@ And this to go from an i2c_client to a v4l2_subdev struct:
struct v4l2_subdev *sd = i2c_get_clientdata(client);
-Finally you need to make a command function to make driver->command()
-call the right subdev_ops functions:
-
-static int subdev_command(struct i2c_client *client, unsigned cmd, void *arg)
-{
- return v4l2_subdev_command(i2c_get_clientdata(client), cmd, arg);
-}
-
-If driver->command is never used then you can leave this out. Eventually the
-driver->command usage should be removed from v4l.
-
Make sure to call v4l2_device_unregister_subdev(sd) when the remove() callback
is called. This will unregister the sub-device from the bridge driver. It is
safe to call this even if the sub-device was never registered.
@@ -375,14 +364,12 @@ 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(adapter, "module_foo", "chipid", 0x36);
+struct v4l2_subdev *sd = v4l2_i2c_new_subdev(v4l2_dev, adapter,
+ "module_foo", "chipid", 0x36);
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. It gets
-the v4l2_device by calling i2c_get_adapdata(adapter), so you should make sure
-to call i2c_set_adapdata(adapter, v4l2_device) when you setup the i2c_adapter
-in your driver.
+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