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V4L/DVB (10489): doc: use consistent naming conventions for vdev and v4l2_dev.

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Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2009-02-07 07:07:04 -03:00 committed by Mauro Carvalho Chehab
parent 8ac05ae319
commit 89aec3e1ba
1 changed files with 11 additions and 11 deletions
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22
Documentation/video4linux/v4l2-framework.txt
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@ -134,7 +134,7 @@ The recommended approach is as follows:
static atomic_t drv_instance = ATOMIC_INIT(0);
static int __devinit drv_probe(struct pci_dev *dev,
static int __devinit drv_probe(struct pci_dev *pdev,
const struct pci_device_id *pci_id)
{
...
@ -218,7 +218,7 @@ to add new ops and categories.
A sub-device driver initializes the v4l2_subdev struct using:
v4l2_subdev_init(subdev, &ops);
v4l2_subdev_init(sd, &ops);
Afterwards you need to initialize subdev->name with a unique name and set the
module owner. This is done for you if you use the i2c helper functions.
@ -226,7 +226,7 @@ module owner. This is done for you if you use the i2c helper functions.
A device (bridge) driver needs to register the v4l2_subdev with the
v4l2_device:
int err = v4l2_device_register_subdev(device, subdev);
int err = v4l2_device_register_subdev(v4l2_dev, sd);
This can fail if the subdev module disappeared before it could be registered.
After this function was called successfully the subdev->dev field points to
@ -234,17 +234,17 @@ the v4l2_device.
You can unregister a sub-device using:
v4l2_device_unregister_subdev(subdev);
v4l2_device_unregister_subdev(sd);
Afterwards the subdev module can be unloaded and subdev->dev == NULL.
Afterwards the subdev module can be unloaded and sd->dev == NULL.
You can call an ops function either directly:
err = subdev->ops->core->g_chip_ident(subdev, &chip);
err = sd->ops->core->g_chip_ident(sd, &chip);
but it is better and easier to use this macro:
err = v4l2_subdev_call(subdev, core, g_chip_ident, &chip);
err = v4l2_subdev_call(sd, core, g_chip_ident, &chip);
The macro will to the right NULL pointer checks and returns -ENODEV if subdev
is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_chip_ident is
@ -252,12 +252,12 @@ NULL, or the actual result of the subdev->ops->core->g_chip_ident ops.
It is also possible to call all or a subset of the sub-devices:
v4l2_device_call_all(dev, 0, core, g_chip_ident, &chip);
v4l2_device_call_all(v4l2_dev, 0, core, g_chip_ident, &chip);
Any subdev that does not support this ops is skipped and error results are
ignored. If you want to check for errors use this:
err = v4l2_device_call_until_err(dev, 0, core, g_chip_ident, &chip);
err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_chip_ident, &chip);
Any error except -ENOIOCTLCMD will exit the loop with that error. If no
errors (except -ENOIOCTLCMD) occured, then 0 is returned.
@ -505,8 +505,8 @@ There are a few useful helper functions:
You can set/get driver private data in the video_device struct using:
void *video_get_drvdata(struct video_device *dev);
void video_set_drvdata(struct video_device *dev, void *data);
void *video_get_drvdata(struct video_device *vdev);
void video_set_drvdata(struct video_device *vdev, void *data);
Note that you can safely call video_set_drvdata() before calling
video_register_device().