Currently VCM drivers power-up the VCM as soon as the VCM's /dev node
is opened and through the runtime-pm device-link to the sensor this
also powers up the sensor.
Powering up the VCM and sensor when the /dev node is opened is undesirable,
without a VCM sensors delay powering up until s_stream(1) is called. This
allows querying / negotiating capabilities without powering things up.
Sometimes a long running daemon like pipewire may keep the /dev node open
all the time. The kernel should still be able to powerdown the VCM + sensor
in this scenario.
VCM drivers should be able to do the same as sensor drivers and only
power-up the VCM when s_stream(1) is called on the VCM subdev, but this
requires that s_stream() is actually called on the VCM when the sensor
starts / stops streaming.
The s_stream() call on sensor subdevs is done by CSI-receiver/ISP drivers.
To avoid needing to change all these call sites to also call s_stream()
on the VCM (if there is one) handle the VCM in the v4l2-core similar to how
the core takes care of turning on/off the privacy LED.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-async.c | 20 +++++++++++++++++++
drivers/media/v4l2-core/v4l2-subdev.c | 28 +++++++++++++++++++++------
include/media/v4l2-subdev.h | 2 ++
3 files changed, 44 insertions(+), 6 deletions(-)
diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
index ee884a8221fb..9b854f1d1051 100644
--- a/drivers/media/v4l2-core/v4l2-async.c
+++ b/drivers/media/v4l2-core/v4l2-async.c
@@ -330,6 +330,11 @@ static int v4l2_async_create_ancillary_links(struct v4l2_async_notifier *n,
return 0;
}
+ if (sd->entity.function == MEDIA_ENT_F_LENS) {
+ dev_dbg(n->sd->dev, "Using %s VCM\n", dev_name(sd->dev));
+ n->sd->vcm = sd;
+ }
+
link = media_create_ancillary_link(&n->sd->entity, &sd->entity);
return IS_ERR(link) ? PTR_ERR(link) : 0;
@@ -871,6 +876,21 @@ void v4l2_async_unregister_subdev(struct v4l2_subdev *sd)
if (!sd->async_list.next)
return;
+#if defined(CONFIG_MEDIA_CONTROLLER)
+ if (sd->entity.function == MEDIA_ENT_F_LENS && sd->v4l2_dev && sd->v4l2_dev->mdev) {
+ struct media_entity *entity;
+
+ media_device_for_each_entity(entity, sd->v4l2_dev->mdev) {
+ struct v4l2_subdev *it = media_entity_to_v4l2_subdev(entity);
+
+ if (it->vcm == sd) {
+ dev_dbg(it->dev, "Clearing VCM\n");
+ it->vcm = NULL;
+ }
+ }
+ }
+#endif
+
v4l2_subdev_put_privacy_led(sd);
mutex_lock(&list_lock);
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 7c5812d55315..24a68d90f686 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -148,17 +148,33 @@ static int subdev_close(struct file *file)
}
#endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
-static void v4l2_subdev_enable_privacy_led(struct v4l2_subdev *sd)
+static void v4l2_subdev_enable_privacy_led_and_vcm(struct v4l2_subdev *sd)
{
#if IS_REACHABLE(CONFIG_LEDS_CLASS)
if (!IS_ERR_OR_NULL(sd->privacy_led))
led_set_brightness(sd->privacy_led,
sd->privacy_led->max_brightness);
#endif
+
+ if (sd->vcm && !sd->vcm_enabled &&
+ v4l2_subdev_has_op(sd->vcm, video, s_stream)) {
+ int ret;
+
+ ret = v4l2_subdev_call(sd->vcm, video, s_stream, 1);
+ if (ret)
+ dev_err(sd->vcm->dev, "Error powering on VCM: %d\n", ret);
+ else
+ sd->vcm_enabled = true;
+ }
}
-static void v4l2_subdev_disable_privacy_led(struct v4l2_subdev *sd)
+static void v4l2_subdev_disable_privacy_led_and_vcm(struct v4l2_subdev *sd)
{
+ if (sd->vcm && sd->vcm_enabled) {
+ v4l2_subdev_call(sd->vcm, video, s_stream, 0);
+ sd->vcm_enabled = false;
+ }
+
#if IS_REACHABLE(CONFIG_LEDS_CLASS)
if (!IS_ERR_OR_NULL(sd->privacy_led))
led_set_brightness(sd->privacy_led, 0);
@@ -466,9 +482,9 @@ static int call_s_stream(struct v4l2_subdev *sd, int enable)
sd->s_stream_enabled = enable;
if (enable)
- v4l2_subdev_enable_privacy_led(sd);
+ v4l2_subdev_enable_privacy_led_and_vcm(sd);
else
- v4l2_subdev_disable_privacy_led(sd);
+ v4l2_subdev_disable_privacy_led_and_vcm(sd);
}
return ret;
@@ -2289,7 +2305,7 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad,
* for all cases.
*/
if (!use_s_stream && !already_streaming)
- v4l2_subdev_enable_privacy_led(sd);
+ v4l2_subdev_enable_privacy_led_and_vcm(sd);
done:
if (!use_s_stream)
@@ -2382,7 +2398,7 @@ int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad,
done:
if (!use_s_stream) {
if (!v4l2_subdev_is_streaming(sd))
- v4l2_subdev_disable_privacy_led(sd);
+ v4l2_subdev_disable_privacy_led_and_vcm(sd);
v4l2_subdev_unlock_state(state);
}
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index bd235d325ff9..6568a0cc070b 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1094,6 +1094,7 @@ struct v4l2_subdev {
*/
struct led_classdev *privacy_led;
+ struct v4l2_subdev *vcm;
/*
* TODO: active_state should most likely be changed from a pointer to an
@@ -1104,6 +1105,7 @@ struct v4l2_subdev {
struct v4l2_subdev_state *active_state;
u64 enabled_pads;
bool s_stream_enabled;
+ bool vcm_enabled;
};
--
2.46.0
