Add a new 'state' field to struct v4l2_subdev to which we can store the
active state of a subdev. This will place the subdev configuration into
a known place, allowing us to use the state directly from the v4l2
framework, thus simplifying the drivers.
Also add functions v4l2_subdev_init_finalize() and
v4l2_subdev_cleanup(), which will allocate and free the active state.
The functions are named in a generic way so that they can be also used
for other subdev initialization work.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-subdev.c | 21 +++++++++++
include/media/v4l2-subdev.h | 51 +++++++++++++++++++++++++++
2 files changed, 72 insertions(+)
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index fe49c86a9b02..bcaf66a1e3d9 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -943,3 +943,24 @@ void v4l2_subdev_notify_event(struct v4l2_subdev *sd,
v4l2_subdev_notify(sd, V4L2_DEVICE_NOTIFY_EVENT, (void *)ev);
}
EXPORT_SYMBOL_GPL(v4l2_subdev_notify_event);
+
+int v4l2_subdev_init_finalize(struct v4l2_subdev *sd)
+{
+ struct v4l2_subdev_state *state;
+
+ state = __v4l2_subdev_state_alloc(sd);
+ if (IS_ERR(state))
+ return PTR_ERR(state);
+
+ sd->state = state;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_init_finalize);
+
+void v4l2_subdev_cleanup(struct v4l2_subdev *sd)
+{
+ __v4l2_subdev_state_free(sd->state);
+ sd->state = NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_cleanup);
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index e52bf508c75b..3aaa7146e5ff 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -898,6 +898,8 @@ struct v4l2_subdev_platform_data {
* @subdev_notifier: A sub-device notifier implicitly registered for the sub-
* device using v4l2_async_register_subdev_sensor().
* @pdata: common part of subdevice platform data
+ * @state: active state for the subdev (NULL for subdevs tracking the state
+ * internally)
*
* Each instance of a subdev driver should create this struct, either
* stand-alone or embedded in a larger struct.
@@ -929,6 +931,19 @@ struct v4l2_subdev {
struct v4l2_async_notifier *notifier;
struct v4l2_async_notifier *subdev_notifier;
struct v4l2_subdev_platform_data *pdata;
+
+ /*
+ * The fields below are private, and should only be accessed via
+ * appropriate functions.
+ */
+
+ /*
+ * TODO: 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
+ * easily catch uses of state in the cases where the driver doesn't
+ * support it.
+ */
+ struct v4l2_subdev_state *state;
};
@@ -1217,4 +1232,40 @@ extern const struct v4l2_subdev_ops v4l2_subdev_call_wrappers;
void v4l2_subdev_notify_event(struct v4l2_subdev *sd,
const struct v4l2_event *ev);
+/**
+ * v4l2_subdev_init_finalize() - Finalize the initialization of the subdevice
+ * @sd: The subdev
+ *
+ * This finalizes the initialization of the subdev, including allocation of
+ * the active state for the subdev.
+ *
+ * This must be called by the subdev drivers that use the centralized active
+ * state, after the subdev struct has been initialized and
+ * media_entity_pads_init() has been called.
+ *
+ * Must call v4l2_subdev_cleanup() when the subdev is being removed.
+ */
+int v4l2_subdev_init_finalize(struct v4l2_subdev *sd);
+
+/**
+ * v4l2_subdev_cleanup() - Release the resources needed by the subdevice
+ * @sd: The subdevice
+ *
+ * This will release the resources allocated in v4l2_subdev_init_finalize.
+ */
+void v4l2_subdev_cleanup(struct v4l2_subdev *sd);
+
+/**
+ * v4l2_subdev_get_active_state() - Return the active subdev state for subdevice
+ * @sd: The subdevice
+ *
+ * Return the active state for the subdevice, or NULL if the subdev does not
+ * support active state.
+ */
+static inline struct v4l2_subdev_state *
+v4l2_subdev_get_active_state(struct v4l2_subdev *sd)
+{
+ return sd->state;
+}
+
#endif
--
2.25.1
