media: v4l2-async: Add waiting subdevices debugfs There is currently little to no information available about the reasons why a v4l2-async device hasn't probed completely. Inspired by the "devices_deferred" debugfs file, add a file to list information about the subdevices that are on waiting lists, for each notifier. This is useful to debug v4l2-async subdevices and notifiers, for instance when doing device bring-up. For instance, a typical output would be: $ cat /sys/kernel/debug/video4linux/pending_async_subdevices ipu1_csi1: [fwnode] dev=20e0000.iomuxc-gpr:ipu1_csi1_mux, node=/soc/bus@2000000/iomuxc-gpr@20e0000/ipu1_csi1_mux ipu1_csi0: [fwnode] dev=20e0000.iomuxc-gpr:ipu1_csi0_mux, node=/soc/bus@2000000/iomuxc-gpr@20e0000/ipu1_csi0_mux imx6-mipi-csi2: [fwnode] dev=1-003c, node=/soc/bus@2100000/i2c@21a4000/camera@3c imx-media: Signed-off-by: Ezequiel Garcia <[email protected]> Reviewed-by: Laurent Pinchart <[email protected]> Tested-by: Kieran Bingham <[email protected]> Signed-off-by: Sakari Ailus <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h index 8ed4218..26296d4 100644 --- a/include/media/v4l2-async.h +++ b/include/media/v4l2-async.h
@@ -11,6 +11,7 @@ #include <linux/list.h> #include <linux/mutex.h> +struct dentry; struct device; struct device_node; struct v4l2_device; @@ -121,6 +122,13 @@ struct v4l2_async_notifier { }; /** + * v4l2_async_debug_init - Initialize debugging tools. + * + * @debugfs_dir: pointer to the parent debugfs &struct dentry + */ +void v4l2_async_debug_init(struct dentry *debugfs_dir); + +/** * v4l2_async_notifier_init - Initialize a notifier. * * @notifier: pointer to &struct v4l2_async_notifier