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.
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| @@ -155,9 +155,25 @@ struct v4l2_subdev_selection { · 154 unmodified lines | |||
| 155 | __u32 reserved[8]; | 155 | __u32 reserved[8]; |
| 156 | }; | 156 | }; |
| 157 | 157 | ||
| 158 | /** | ||
| 159 | * struct v4l2_subdev_capability - subdev capabilities | ||
| 160 | * @version: the driver versioning number | ||
| 161 | * @capabilities: the subdev capabilities, see V4L2_SUBDEV_CAP_* | ||
| 162 | * @reserved: for future use, set to zero for now | ||
| 163 | */ | ||
| 164 | struct v4l2_subdev_capability { | ||
| 165 | __u32 version; | ||
| 166 | __u32 capabilities; | ||
| 167 | __u32 reserved[14]; | ||
| 168 | }; | ||
| 169 | |||
| 170 | /* The v4l2 sub-device video device node is registered in read-only mode. */ | ||
| 171 | #define V4L2_SUBDEV_CAP_RO_SUBDEV BIT(0) | ||
| 172 | |||
| 158 | /* Backwards compatibility define --- to be removed */ | 173 | /* Backwards compatibility define --- to be removed */ |
| 159 | #define v4l2_subdev_edid v4l2_edid | 174 | #define v4l2_subdev_edid v4l2_edid |
| 160 | 175 | ||
| 176 | #define VIDIOC_SUBDEV_QUERYCAP _IOR('V', 0, struct v4l2_subdev_capability) | ||
| 161 | #define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format) | 177 | #define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format) |
| 162 | #define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format) | 178 | #define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format) |
| 163 | #define VIDIOC_SUBDEV_G_FRAME_INTERVAL _IOWR('V', 21, struct v4l2_subdev_frame_interval) | 179 | #define VIDIOC_SUBDEV_G_FRAME_INTERVAL _IOWR('V', 21, struct v4l2_subdev_frame_interval) |