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media: subdev: Improve v4l2_subdev_enable/disable_streams_fallback

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v4l2_subdev_enable/disable_streams_fallback() supports falling back to
.s_stream() for subdevs with a single source pad. It also tracks the
enabled streams for that one pad in the sd->enabled_streams field.

Tracking the enabled streams with sd->enabled_streams does not make
sense, as with .s_stream() there can only be a single stream per pad.
Thus, as the v4l2_subdev_enable/disable_streams_fallback() only supports
a single source pad, all we really need is a boolean which tells whether
streaming has been enabled on this pad or not.

However, as we only need a true/false state for a pad (instead of
tracking which streams have been enabled for a pad), we can easily
extend the fallback mechanism to support multiple source pads as we only
need to keep track of which pads have been enabled.

Change the sd->enabled_streams field to sd->enabled_pads, which is a
64-bit bitmask tracking the enabled source pads. With this change we can
remove the restriction that
v4l2_subdev_enable/disable_streams_fallback() only supports a single
source pad.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Umang Jain <umang.jain@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
This commit is contained in:
Tomi Valkeinen 2024-04-24 18:39:08 +03:00 committed by Hans Verkuil
parent 1d7804281d
commit 61d6c8c896
2 changed files with 44 additions and 33 deletions
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68
drivers/media/v4l2-core/v4l2-subdev.c
View file

@ -2159,37 +2159,43 @@ static int v4l2_subdev_enable_streams_fallback(struct v4l2_subdev *sd, u32 pad,
u64 streams_mask)
{
struct device *dev = sd->entity.graph_obj.mdev->dev;
unsigned int i;
int ret;
/*
* The subdev doesn't implement pad-based stream enable, fall back
* on the .s_stream() operation. This can only be done for subdevs that
* have a single source pad, as sd->enabled_streams is global to the
* subdev.
* to the .s_stream() operation.
*/
if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE))
return -EOPNOTSUPP;
for (i = 0; i < sd->entity.num_pads; ++i) {
if (i != pad && sd->entity.pads[i].flags & MEDIA_PAD_FL_SOURCE)
return -EOPNOTSUPP;
}
/*
* .s_stream() means there is no streams support, so the only allowed
* stream is the implicit stream 0.
*/
if (streams_mask != BIT_ULL(0))
return -EOPNOTSUPP;
if (sd->enabled_streams & streams_mask) {
dev_dbg(dev, "set of streams %#llx already enabled on %s:%u\n",
streams_mask, sd->entity.name, pad);
/*
* We use a 64-bit bitmask for tracking enabled pads, so only subdevices
* with 64 pads or less can be supported.
*/
if (pad >= sizeof(sd->enabled_pads) * BITS_PER_BYTE)
return -EOPNOTSUPP;
if (sd->enabled_pads & BIT_ULL(pad)) {
dev_dbg(dev, "pad %u already enabled on %s\n",
pad, sd->entity.name);
return -EALREADY;
}
/* Start streaming when the first streams are enabled. */
if (!sd->enabled_streams) {
/* Start streaming when the first pad is enabled. */
if (!sd->enabled_pads) {
ret = v4l2_subdev_call(sd, video, s_stream, 1);
if (ret)
return ret;
}
sd->enabled_streams |= streams_mask;
sd->enabled_pads |= BIT_ULL(pad);
return 0;
}
@ -2276,37 +2282,43 @@ static int v4l2_subdev_disable_streams_fallback(struct v4l2_subdev *sd, u32 pad,
u64 streams_mask)
{
struct device *dev = sd->entity.graph_obj.mdev->dev;
unsigned int i;
int ret;
/*
* If the subdev doesn't implement pad-based stream enable, fall back
* on the .s_stream() operation. This can only be done for subdevs that
* have a single source pad, as sd->enabled_streams is global to the
* subdev.
* If the subdev doesn't implement pad-based stream enable, fall back
* to the .s_stream() operation.
*/
if (!(sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE))
return -EOPNOTSUPP;
for (i = 0; i < sd->entity.num_pads; ++i) {
if (i != pad && sd->entity.pads[i].flags & MEDIA_PAD_FL_SOURCE)
return -EOPNOTSUPP;
}
/*
* .s_stream() means there is no streams support, so the only allowed
* stream is the implicit stream 0.
*/
if (streams_mask != BIT_ULL(0))
return -EOPNOTSUPP;
if ((sd->enabled_streams & streams_mask) != streams_mask) {
dev_dbg(dev, "set of streams %#llx already disabled on %s:%u\n",
streams_mask, sd->entity.name, pad);
/*
* We use a 64-bit bitmask for tracking enabled pads, so only subdevices
* with 64 pads or less can be supported.
*/
if (pad >= sizeof(sd->enabled_pads) * BITS_PER_BYTE)
return -EOPNOTSUPP;
if (!(sd->enabled_pads & BIT_ULL(pad))) {
dev_dbg(dev, "pad %u already disabled on %s\n",
pad, sd->entity.name);
return -EALREADY;
}
/* Stop streaming when the last streams are disabled. */
if (!(sd->enabled_streams & ~streams_mask)) {
if (!(sd->enabled_pads & ~BIT_ULL(pad))) {
ret = v4l2_subdev_call(sd, video, s_stream, 0);
if (ret)
return ret;
}
sd->enabled_streams &= ~streams_mask;
sd->enabled_pads &= ~BIT_ULL(pad);
return 0;
}

9
include/media/v4l2-subdev.h
View file

@ -1041,10 +1041,9 @@ struct v4l2_subdev_platform_data {
* @active_state: Active state for the subdev (NULL for subdevs tracking the
* state internally). Initialized by calling
* v4l2_subdev_init_finalize().
* @enabled_streams: Bitmask of enabled streams used by
* v4l2_subdev_enable_streams() and
* v4l2_subdev_disable_streams() helper functions for fallback
* cases.
* @enabled_pads: Bitmask of enabled pads used by v4l2_subdev_enable_streams()
* and v4l2_subdev_disable_streams() helper functions for
* fallback cases.
* @s_stream_enabled: Tracks whether streaming has been enabled with s_stream.
* This is only for call_s_stream() internal use.
*
@ -1094,7 +1093,7 @@ struct v4l2_subdev {
* doesn't support it.
*/
struct v4l2_subdev_state *active_state;
u64 enabled_streams;
u64 enabled_pads;
bool s_stream_enabled;
};