[PATCH v3 06/11] v4l: subdev: Make the v4l2-subdev core code enable/disable the privacy LED if present

Hans de Goede
2022-12-16T11:31:35Z

Extend the call_s_stream() wrapper to enable/disable sensor privacy LEDs
for sensors with a privacy LED, rather then having to duplicate this code
in all the sensor drivers.

Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/media/v4l2-core/v4l2-subdev.c | 40 +++++++++++++++++++++++++++
include/media/v4l2-subdev.h | 3 ++
2 files changed, 43 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 4988a25bd8f4..7344f6cd58b7 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -318,10 +318,44 @@ static int call_get_mbus_config(struct v4l2_subdev *sd, unsigned int pad,
sd->ops->pad->get_mbus_config(sd, pad, config);
}

+#if IS_REACHABLE(CONFIG_LEDS_CLASS)
+#include <linux/leds.h>
+
+static void call_s_stream_update_pled(struct v4l2_subdev *sd, int enable)
+{
+ if (!sd->dev)
+ return;
+
+ /* Try to get privacy-led once, at first s_stream() */
+ if (!sd->privacy_led)
+ sd->privacy_led = led_get(sd->dev, "privacy-led");
+
+ if (IS_ERR(sd->privacy_led))
+ return;
+
+ mutex_lock(&sd->privacy_led->led_access);
+
+ if (enable) {
+ led_sysfs_disable(sd->privacy_led);
+ led_trigger_remove(sd->privacy_led);
+ led_set_brightness(sd->privacy_led, sd->privacy_led->max_brightness);
+ } else {
+ led_set_brightness(sd->privacy_led, 0);
+ led_sysfs_enable(sd->privacy_led);
+ }
+
+ mutex_unlock(&sd->privacy_led->led_access);
+}
+#else
+static void call_s_stream_update_pled(struct v4l2_subdev *sd, int enable) {}
+#endif
+
static int call_s_stream(struct v4l2_subdev *sd, int enable)
{
int ret;

+ call_s_stream_update_pled(sd, enable);
+
ret = sd->ops->video->s_stream(sd, enable);

if (!enable && ret < 0) {
@@ -1050,6 +1084,11 @@ EXPORT_SYMBOL_GPL(__v4l2_subdev_init_finalize);

void v4l2_subdev_cleanup(struct v4l2_subdev *sd)
{
+#if IS_REACHABLE(CONFIG_LEDS_CLASS)
+ if (!IS_ERR_OR_NULL(sd->privacy_led))
+ led_put(sd->privacy_led);
+#endif
+
__v4l2_subdev_state_free(sd->active_state);
sd->active_state = NULL;
}
@@ -1090,6 +1129,7 @@ void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
sd->grp_id = 0;
sd->dev_priv = NULL;
sd->host_priv = NULL;
+ sd->privacy_led = NULL;
#if defined(CONFIG_MEDIA_CONTROLLER)
sd->entity.name = sd->name;
sd->entity.obj_type = MEDIA_ENTITY_TYPE_V4L2_SUBDEV;
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index b15fa9930f30..0547313f98cc 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -38,6 +38,7 @@ struct v4l2_subdev;
struct v4l2_subdev_fh;
struct tuner_setup;
struct v4l2_mbus_frame_desc;
+struct led_classdev;

/**
* struct v4l2_decode_vbi_line - used to decode_vbi_line
@@ -982,6 +983,8 @@ struct v4l2_subdev {
* appropriate functions.
*/

+ struct led_classdev *privacy_led;
+
/*
* TODO: active_state should most likely be changed from a pointer to an
* embedded field. For the time being it's kept as a pointer to more
--
2.38.1