From f75c431e54e2e43c91fe267097b974ff2e5dc668 Mon Sep 17 00:00:00 2001 From: Jacopo Mondi Date: Thu, 7 May 2020 17:12:50 +0200 Subject: media: v4l2-dev: Add v4l2_device_register_ro_subdev_node() Add to the V4L2 core a function to register device nodes for video subdevices in read-only mode. Registering a device node in read-only mode is useful to expose to userspace the current sub-device configuration, without allowing application to change it by using the V4L2 subdevice ioctls. Acked-by: Sakari Ailus Signed-off-by: Jacopo Mondi Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-subdev.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'drivers/media/v4l2-core/v4l2-subdev.c') diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index a376b351135f..1dc263c2ca0a 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -331,6 +331,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) struct v4l2_fh *vfh = file->private_data; #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API) struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh); + bool ro_subdev = test_bit(V4L2_FL_SUBDEV_RO_DEVNODE, &vdev->flags); #endif int rval; @@ -477,6 +478,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_SUBDEV_S_FMT: { struct v4l2_subdev_format *format = arg; + if (format->which != V4L2_SUBDEV_FORMAT_TRY && ro_subdev) + return -EPERM; + memset(format->reserved, 0, sizeof(format->reserved)); memset(format->format.reserved, 0, sizeof(format->format.reserved)); return v4l2_subdev_call(sd, pad, set_fmt, subdev_fh->pad, format); @@ -504,6 +508,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) struct v4l2_subdev_crop *crop = arg; struct v4l2_subdev_selection sel; + if (crop->which != V4L2_SUBDEV_FORMAT_TRY && ro_subdev) + return -EPERM; + memset(crop->reserved, 0, sizeof(crop->reserved)); memset(&sel, 0, sizeof(sel)); sel.which = crop->which; @@ -545,6 +552,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_SUBDEV_S_FRAME_INTERVAL: { struct v4l2_subdev_frame_interval *fi = arg; + if (ro_subdev) + return -EPERM; + memset(fi->reserved, 0, sizeof(fi->reserved)); return v4l2_subdev_call(sd, video, s_frame_interval, arg); } @@ -568,6 +578,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_SUBDEV_S_SELECTION: { struct v4l2_subdev_selection *sel = arg; + if (sel->which != V4L2_SUBDEV_FORMAT_TRY && ro_subdev) + return -EPERM; + memset(sel->reserved, 0, sizeof(sel->reserved)); return v4l2_subdev_call( sd, pad, set_selection, subdev_fh->pad, sel); @@ -604,6 +617,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) return v4l2_subdev_call(sd, video, g_dv_timings, arg); case VIDIOC_SUBDEV_S_DV_TIMINGS: + if (ro_subdev) + return -EPERM; + return v4l2_subdev_call(sd, video, s_dv_timings, arg); case VIDIOC_SUBDEV_G_STD: @@ -612,6 +628,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_SUBDEV_S_STD: { v4l2_std_id *std = arg; + if (ro_subdev) + return -EPERM; + return v4l2_subdev_call(sd, video, s_std, *std); } -- cgit v1.2.3