diff options
| author | Hans Verkuil <hans.verkuil@cisco.com> | 2012-05-06 09:28:27 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-05-14 09:31:03 -0300 |
| commit | a3d6e8cc0e6ddc8b3cfdeb3c979f07ed1aa528b3 (patch) | |
| tree | 60e69fcac849b505328e5755ee71195d0bc6728b /drivers/media/video/gspca/gspca.h | |
| parent | 254902b01d2acc6aced99ec17caa4c6cd890cdea (diff) | |
[media] gspca: Switch to V4L2 core locking, except for the buffer queuing ioctls
Due to latency concerns the VIDIOC_QBUF, DQBUF and QUERYBUF do not use the
core lock, instead they rely only on queue_lock.
Changes by HdG:
1) Change release from the video_device to the v4l2_device, to avoid a
race on disconnect.
2) Adjust for the V4L2 core changes which cause non ioctl fops to no longer
take the V4L2 core lock.
[mchehab@redhat.com: fix a merge conflict]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/video/gspca/gspca.h')
| -rw-r--r-- | drivers/media/video/gspca/gspca.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h index c1ebf7cd45b..436d881ce44 100644 --- a/drivers/media/video/gspca/gspca.h +++ b/drivers/media/video/gspca/gspca.h @@ -163,6 +163,7 @@ struct gspca_dev { struct v4l2_device v4l2_dev; struct usb_device *dev; struct file *capt_file; /* file doing video capture */ + /* protected by queue_lock */ #if defined(CONFIG_INPUT) || defined(CONFIG_INPUT_MODULE) struct input_dev *input_dev; char phys[64]; /* physical device path */ @@ -192,7 +193,7 @@ struct gspca_dev { u8 fr_o; /* next frame to dequeue */ __u8 last_packet_type; __s8 empty_packet; /* if (-1) don't check empty packets */ - __u8 streaming; + __u8 streaming; /* protected by both mutexes (*) */ __u8 curr_mode; /* current camera mode */ __u32 pixfmt; /* current mode parameters */ @@ -214,6 +215,10 @@ struct gspca_dev { __u8 iface; /* USB interface number */ __u8 alt; /* USB alternate setting */ u8 audio; /* presence of audio device */ + + /* (*) These variables are proteced by both usb_lock and queue_lock, + that is any code setting them is holding *both*, which means that + any code getting them needs to hold at least one of them */ }; int gspca_dev_probe(struct usb_interface *intf, |