Re: [RFC 18/19] v4l2-fwnode: Add abstracted sub-device notifiers

Niklas Söderlund
2017-07-18T21:19:25Z

Hi Sakari,

Thanks for your hard work!

On 2017-07-18 22:04:00 +0300, Sakari Ailus wrote:
> Add notifiers for sub-devices. The notifiers themselves are not visible for
> the sub-device drivers but instead are accessed through interface functions

I might be missing it, but I can't find a interface function to set the
bound()/unbind() callbacks on a sub-notifiers :-) Is this intentional or
only not present in this RFC?

> v4l2_subdev_fwnode_endpoints_parse() and
> v4l2_subdev_fwnode_reference_parse_sensor_common().

>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
> drivers/media/v4l2-core/v4l2-async.c | 27 +++++++++++++++++----
> drivers/media/v4l2-core/v4l2-subdev.c | 44 +++++++++++++++++++++++++++++++++--
> include/media/v4l2-fwnode.h | 1 +
> include/media/v4l2-subdev.h | 11 +++++++++
> 4 files changed, 77 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index 55fa7106345c..411deadf5d85 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -134,10 +134,14 @@ static int v4l2_async_test_notify(struct v4l2_async_notifier *notifier,
>
> if (notifier->bound) {
> ret = notifier->bound(notifier, sd, asd);
> - if (ret < 0) {
> - v4l2_device_unregister_subdev(sd);
> - return ret;
> - }
> + if (ret < 0)
> + goto err_unregister;
> + }
> +
> + if (sd->subnotifier) {
> + ret = v4l2_async_subnotifier_register(sd, sd->subnotifier);
> + if (ret < 0)
> + goto err_unbind;
> }
>
> /* Remove from the waiting list */
> @@ -152,6 +156,15 @@ static int v4l2_async_test_notify(struct v4l2_async_notifier *notifier,
> return notifier->complete(notifier);
>
> return 0;
> +
> +err_unbind:
> + if (notifier->unbind)
> + notifier->unbind(notifier, sd, asd);
> +
> +err_unregister:
> + v4l2_device_unregister_subdev(sd);
> +
> + return ret;
> }
>
> static void v4l2_async_cleanup(struct v4l2_subdev *sd)
> @@ -283,6 +296,9 @@ v4l2_async_do_notifier_unregister(struct v4l2_async_notifier *notifier,
> /* If we handled USB devices, we'd have to lock the parent too */
> device_release_driver(d);
>
> + if (sd->subnotifier)
> + v4l2_async_subnotifier_unregister(sd->subnotifier);
> +
> if (notifier->unbind)
> notifier->unbind(notifier, sd, sd->asd);
>
> @@ -396,6 +412,9 @@ void v4l2_async_unregister_subdev(struct v4l2_subdev *sd)
>
> v4l2_async_cleanup(sd);
>
> + if (sd->subnotifier)
> + v4l2_async_subnotifier_unregister(sd->subnotifier);
> +
> if (notifier->unbind)
> notifier->unbind(notifier, sd, sd->asd);
>
> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> index 43fefa73e0a3..a6976d4a52ac 100644
> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> @@ -25,9 +25,10 @@
>
> #include <media/v4l2-ctrls.h>
> #include <media/v4l2-device.h>
> -#include <media/v4l2-ioctl.h>
> -#include <media/v4l2-fh.h>
> #include <media/v4l2-event.h>
> +#include <media/v4l2-fh.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-ioctl.h>
>
> static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
> {
> @@ -626,3 +627,42 @@ 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);
> +
> +static struct v4l2_async_notifier *v4l2_subdev_get_subnotifier(
> + struct v4l2_subdev *sd)
> +{
> + if (sd->subnotifier)
> + return sd->subnotifier;
> +
> + return (sd->subnotifier = devm_kzalloc(
> + sd->dev, sizeof(*sd->subnotifier), GFP_KERNEL));
> +}
> +
> +int v4l2_subdev_fwnode_endpoints_parse(
> + struct v4l2_subdev *sd, size_t asd_struct_size,
> + int (*parse_single)(struct device *dev,
> + struct v4l2_fwnode_endpoint *vep,
> + struct v4l2_async_subdev *asd))
> +{
> + struct v4l2_async_notifier *subnotifier =
> + v4l2_subdev_get_subnotifier(sd);
> +
> + if (!subnotifier)
> + return -ENOMEM;
> +
> + return v4l2_fwnode_endpoints_parse(sd->dev, subnotifier,
> + asd_struct_size, parse_single);
> +}
> +EXPORT_SYMBOL_GPL(v4l2_subdev_fwnode_endpoints_parse);
> +
> +int v4l2_subdev_fwnode_reference_parse_sensor_common(struct v4l2_subdev *sd)
> +{
> + struct v4l2_async_notifier *subnotifier =
> + v4l2_subdev_get_subnotifier(sd);
> +
> + if (!subnotifier)
> + return -ENOMEM;
> +
> + return v4l2_fwnode_reference_parse_sensor_common(sd->dev, subnotifier);
> +}
> +EXPORT_SYMBOL_GPL(v4l2_subdev_fwnode_reference_parse_sensor_common);
> diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h
> index 8cd4f8a75c3d..0a3f869ead52 100644
> --- a/include/media/v4l2-fwnode.h
> +++ b/include/media/v4l2-fwnode.h
> @@ -27,6 +27,7 @@
> struct fwnode_handle;
> struct v4l2_async_notifier;
> struct v4l2_async_subdev;
> +struct v4l2_subdev;
>
> /**
> * struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 0f92ebd2d710..e309a2e2030b 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -43,6 +43,7 @@ struct v4l2_ctrl_handler;
> struct v4l2_event;
> struct v4l2_event_subscription;
> struct v4l2_fh;
> +struct v4l2_fwnode_endpoint;
> struct v4l2_subdev;
> struct v4l2_subdev_fh;
> struct tuner_setup;
> @@ -793,6 +794,7 @@ struct v4l2_subdev_platform_data {
> * list.
> * @asd: Pointer to respective &struct v4l2_async_subdev.
> * @notifier: Pointer to the managing notifier.
> + * @subnotifier: Pointer to the async sub-device notifier.
> * @pdata: common part of subdevice platform data
> *
> * Each instance of a subdev driver should create this struct, either
> @@ -823,6 +825,7 @@ struct v4l2_subdev {
> struct list_head async_list;
> struct v4l2_async_subdev *asd;
> struct v4l2_async_notifier *notifier;
> + struct v4l2_async_notifier *subnotifier;
> struct v4l2_subdev_platform_data *pdata;
> };
>
> @@ -1001,4 +1004,12 @@ void v4l2_subdev_init(struct v4l2_subdev *sd,
> void v4l2_subdev_notify_event(struct v4l2_subdev *sd,
> const struct v4l2_event *ev);
>
> +int v4l2_subdev_fwnode_endpoints_parse(
> + struct v4l2_subdev *sd, size_t asd_struct_size,
> + int (*parse_single)(struct device *dev,
> + struct v4l2_fwnode_endpoint *vep,
> + struct v4l2_async_subdev *asd));
> +
> +int v4l2_subdev_fwnode_reference_parse_sensor_common(struct v4l2_subdev *sd);
> +
> #endif
> --
> 2.11.0
>

--
Regards,
Niklas Söderlund