[media] soc-camera: add V4L2-async support

Add support for asynchronous subdevice probing, using the v4l2-async API.
The legacy synchronous mode is still supported too, which allows to
gradually update drivers and platforms. The selected approach adds a
notifier for each struct soc_camera_device instance, i.e. for each video
device node, even when there are multiple such instances registered with a
single soc-camera host simultaneously.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 22 insertions, 1 deletions

diff --git a/include/media/soc_camera.h b/include/media/soc_camera.h
index f582323fafb7..906ed98c6e95 100644
--- a/include/media/soc_camera.h
+++ b/include/media/soc_camera.h
@@ -19,11 +19,13 @@
 #include <linux/videodev2.h>
 #include <media/videobuf-core.h>
 #include <media/videobuf2-core.h>
+#include <media/v4l2-async.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 
 struct file;
 struct soc_camera_desc;
+struct soc_camera_async_client;
 
 struct soc_camera_device {
         struct list_head list;          /* list of all registered devices */
@@ -50,6 +52,9 @@ struct soc_camera_device {
         int use_count;
         struct file *streamer;          /* stream owner */
         struct v4l2_clk *clk;
+        /* Asynchronous subdevice management */
+        struct soc_camera_async_client *sasc;
+        /* video buffer queue */
         union {
                 struct videobuf_queue vb_vidq;
                 struct vb2_queue vb2_vidq;
@@ -59,16 +64,30 @@ struct soc_camera_device {
 /* Host supports programmable stride */
 #define SOCAM_HOST_CAP_STRIDE           (1 << 0)
 
+enum soc_camera_subdev_role {
+        SOCAM_SUBDEV_DATA_SOURCE = 1,
+        SOCAM_SUBDEV_DATA_SINK,
+        SOCAM_SUBDEV_DATA_PROCESSOR,
+};
+
+struct soc_camera_async_subdev {
+        struct v4l2_async_subdev asd;
+        enum soc_camera_subdev_role role;
+};
+
 struct soc_camera_host {
         struct v4l2_device v4l2_dev;
         struct list_head list;
-        struct mutex host_lock;         /* Protect pipeline modifications */
+        struct mutex host_lock;         /* Main synchronisation lock */
+        struct mutex clk_lock;          /* Protect pipeline modifications */
         unsigned char nr;               /* Host number */
         u32 capabilities;
         struct soc_camera_device *icd;  /* Currently attached client */
         void *priv;
         const char *drv_name;
         struct soc_camera_host_ops *ops;
+        struct v4l2_async_subdev **asd; /* Flat array, arranged in groups */
+        int *asd_sizes;                 /* 0-terminated array of asd group sizes */
 };
 
 struct soc_camera_host_ops {
@@ -161,6 +180,7 @@ struct soc_camera_host_desc {
 };
 
 /*
+ * Platform data for "soc-camera-pdrv"
  * This MUST be kept binary-identical to struct soc_camera_link below, until
  * it is completely replaced by this one, after which we can split it into its
  * two components.
@@ -326,6 +346,7 @@ static inline void soc_camera_limit_side(int *start, int *length,
 unsigned long soc_camera_apply_board_flags(struct soc_camera_subdev_desc *ssdd,
                                            const struct v4l2_mbus_config *cfg);
 
+int soc_camera_power_init(struct device *dev, struct soc_camera_subdev_desc *ssdd);
 int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd,
                         struct v4l2_clk *clk);
 int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd,