diff options
| author | Hans Verkuil <hans.verkuil@cisco.com> | 2020-05-07 17:12:52 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2020-05-12 17:05:31 +0200 |
| commit | 6446ec6cbf46483737e832cd6050885fa8eb87fa (patch) | |
| tree | aa755171f8db869b92ecf646023c1d9e48cae10a | |
| parent | fb15db8c0060e73317a7872986b909343504eb84 (diff) | |
| download | linux-6446ec6cbf46483737e832cd6050885fa8eb87fa.tar.bz2 | |
media: v4l2-subdev: add VIDIOC_SUBDEV_QUERYCAP ioctl
While normal video/radio/vbi/swradio nodes have a proper QUERYCAP ioctl
that apps can call to determine that it is indeed a V4L2 device, there
is currently no equivalent for v4l-subdev nodes. Adding this ioctl will
solve that, and it will allow utilities like v4l2-compliance to be used
with these devices as well.
SUBDEV_QUERYCAP currently returns the version and capabilities of the
subdevice. Define a capability flag to report if the subdevice is
registered in read-only mode.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-subdev.c | 11 | ||||
| -rw-r--r-- | include/uapi/linux/v4l2-subdev.h | 16 |
2 files changed, 27 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index 174778f9c0bc..665b0c0f74cf 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -15,6 +15,7 @@ #include <linux/types.h> #include <linux/videodev2.h> #include <linux/export.h> +#include <linux/version.h> #include <media/v4l2-ctrls.h> #include <media/v4l2-device.h> @@ -344,6 +345,16 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) int rval; switch (cmd) { + case VIDIOC_SUBDEV_QUERYCAP: { + struct v4l2_subdev_capability *cap = arg; + + memset(cap->reserved, 0, sizeof(cap->reserved)); + cap->version = LINUX_VERSION_CODE; + cap->capabilities = ro_subdev ? V4L2_SUBDEV_CAP_RO_SUBDEV : 0; + + return 0; + } + case VIDIOC_QUERYCTRL: /* * TODO: this really should be folded into v4l2_queryctrl (this diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h index 03970ce30741..5d2a1dab7911 100644 --- a/include/uapi/linux/v4l2-subdev.h +++ b/include/uapi/linux/v4l2-subdev.h @@ -155,9 +155,25 @@ struct v4l2_subdev_selection { __u32 reserved[8]; }; +/** + * struct v4l2_subdev_capability - subdev capabilities + * @version: the driver versioning number + * @capabilities: the subdev capabilities, see V4L2_SUBDEV_CAP_* + * @reserved: for future use, set to zero for now + */ +struct v4l2_subdev_capability { + __u32 version; + __u32 capabilities; + __u32 reserved[14]; +}; + +/* The v4l2 sub-device video device node is registered in read-only mode. */ +#define V4L2_SUBDEV_CAP_RO_SUBDEV BIT(0) + /* Backwards compatibility define --- to be removed */ #define v4l2_subdev_edid v4l2_edid +#define VIDIOC_SUBDEV_QUERYCAP _IOR('V', 0, struct v4l2_subdev_capability) #define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_G_FRAME_INTERVAL _IOWR('V', 21, struct v4l2_subdev_frame_interval) |