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Diffstat (limited to 'include/media/v4l2-mc.h')
-rw-r--r-- | include/media/v4l2-mc.h | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h new file mode 100644 index 0000000000..b39586dfba --- /dev/null +++ b/include/media/v4l2-mc.h @@ -0,0 +1,223 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * v4l2-mc.h - Media Controller V4L2 types and prototypes + * + * Copyright (C) 2016 Mauro Carvalho Chehab <mchehab@kernel.org> + * Copyright (C) 2006-2010 Nokia Corporation + * Copyright (c) 2016 Intel Corporation. + */ + +#ifndef _V4L2_MC_H +#define _V4L2_MC_H + +#include <media/media-device.h> +#include <media/v4l2-dev.h> +#include <media/v4l2-subdev.h> +#include <linux/types.h> + +/* We don't need to include pci.h or usb.h here */ +struct pci_dev; +struct usb_device; + +#ifdef CONFIG_MEDIA_CONTROLLER +/** + * v4l2_mc_create_media_graph() - create Media Controller links at the graph. + * + * @mdev: pointer to the &media_device struct. + * + * Add links between the entities commonly found on PC customer's hardware at + * the V4L2 side: camera sensors, audio and video PLL-IF decoders, tuners, + * analog TV decoder and I/O entities (video, VBI and Software Defined Radio). + * + * .. note:: + * + * Webcams are modelled on a very simple way: the sensor is + * connected directly to the I/O entity. All dirty details, like + * scaler and crop HW are hidden. While such mapping is enough for v4l2 + * interface centric PC-consumer's hardware, V4L2 subdev centric camera + * hardware should not use this routine, as it will not build the right graph. + */ +int v4l2_mc_create_media_graph(struct media_device *mdev); + +/** + * v4l_enable_media_source() - Hold media source for exclusive use + * if free + * + * @vdev: pointer to struct video_device + * + * This interface calls enable_source handler to determine if + * media source is free for use. The enable_source handler is + * responsible for checking is the media source is free and + * start a pipeline between the media source and the media + * entity associated with the video device. This interface + * should be called from v4l2-core and dvb-core interfaces + * that change the source configuration. + * + * Return: returns zero on success or a negative error code. + */ +int v4l_enable_media_source(struct video_device *vdev); + +/** + * v4l_disable_media_source() - Release media source + * + * @vdev: pointer to struct video_device + * + * This interface calls disable_source handler to release + * the media source. The disable_source handler stops the + * active media pipeline between the media source and the + * media entity associated with the video device. + * + * Return: returns zero on success or a negative error code. + */ +void v4l_disable_media_source(struct video_device *vdev); + +/* + * v4l_vb2q_enable_media_tuner - Hold media source for exclusive use + * if free. + * @q - pointer to struct vb2_queue + * + * Wrapper for v4l_enable_media_source(). This function should + * be called from v4l2-core to enable the media source with + * pointer to struct vb2_queue as the input argument. Some + * v4l2-core interfaces don't have access to video device and + * this interface finds the struct video_device for the q and + * calls v4l_enable_media_source(). + */ +int v4l_vb2q_enable_media_source(struct vb2_queue *q); + +/** + * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a + * source subdev to a sink pad. + * + * @src_sd: pointer to a source subdev + * @sink: pointer to a sink pad + * @flags: the link flags + * + * This function searches for fwnode endpoint connections from a source + * subdevice to a single sink pad, and if suitable connections are found, + * translates them into media links to that pad. The function can be + * called by the sink, in its v4l2-async notifier bound callback, to create + * links from a bound source subdevice. + * + * The @flags argument specifies the link flags. The caller shall ensure that + * the flags are valid regardless of the number of links that may be created. + * For instance, setting the MEDIA_LNK_FL_ENABLED flag will cause all created + * links to be enabled, which isn't valid if more than one link is created. + * + * .. note:: + * + * Any sink subdevice that calls this function must implement the + * .get_fwnode_pad media operation in order to verify endpoints passed + * to the sink are owned by the sink. + * + * Return 0 on success or a negative error code on failure. + */ +int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd, + struct media_pad *sink, u32 flags); + +/** + * v4l2_create_fwnode_links - Create fwnode-based links from a source + * subdev to a sink subdev. + * + * @src_sd: pointer to a source subdevice + * @sink_sd: pointer to a sink subdevice + * + * This function searches for any and all fwnode endpoint connections + * between source and sink subdevices, and translates them into media + * links. The function can be called by the sink subdevice, in its + * v4l2-async notifier subdev bound callback, to create all links from + * a bound source subdevice. + * + * .. note:: + * + * Any sink subdevice that calls this function must implement the + * .get_fwnode_pad media operation in order to verify endpoints passed + * to the sink are owned by the sink. + * + * Return 0 on success or a negative error code on failure. + */ +int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd, + struct v4l2_subdev *sink_sd); + +/** + * v4l2_pipeline_pm_get - Increase the use count of a pipeline + * @entity: The root entity of a pipeline + * + * Update the use count of all entities in the pipeline and power entities on. + * + * This function is intended to be called in video node open. It uses + * struct media_entity.use_count to track the power status. The use + * of this function should be paired with v4l2_pipeline_link_notify(). + * + * Return 0 on success or a negative error code on failure. + */ +int v4l2_pipeline_pm_get(struct media_entity *entity); + +/** + * v4l2_pipeline_pm_put - Decrease the use count of a pipeline + * @entity: The root entity of a pipeline + * + * Update the use count of all entities in the pipeline and power entities off. + * + * This function is intended to be called in video node release. It uses + * struct media_entity.use_count to track the power status. The use + * of this function should be paired with v4l2_pipeline_link_notify(). + */ +void v4l2_pipeline_pm_put(struct media_entity *entity); + + +/** + * v4l2_pipeline_link_notify - Link management notification callback + * @link: The link + * @flags: New link flags that will be applied + * @notification: The link's state change notification type (MEDIA_DEV_NOTIFY_*) + * + * React to link management on powered pipelines by updating the use count of + * all entities in the source and sink sides of the link. Entities are powered + * on or off accordingly. The use of this function should be paired + * with v4l2_pipeline_pm_{get,put}(). + * + * Return 0 on success or a negative error code on failure. Powering entities + * off is assumed to never fail. This function will not fail for disconnection + * events. + */ +int v4l2_pipeline_link_notify(struct media_link *link, u32 flags, + unsigned int notification); + +#else /* CONFIG_MEDIA_CONTROLLER */ + +static inline int v4l2_mc_create_media_graph(struct media_device *mdev) +{ + return 0; +} + +static inline int v4l_enable_media_source(struct video_device *vdev) +{ + return 0; +} + +static inline void v4l_disable_media_source(struct video_device *vdev) +{ +} + +static inline int v4l_vb2q_enable_media_source(struct vb2_queue *q) +{ + return 0; +} + +static inline int v4l2_pipeline_pm_get(struct media_entity *entity) +{ + return 0; +} + +static inline void v4l2_pipeline_pm_put(struct media_entity *entity) +{} + +static inline int v4l2_pipeline_link_notify(struct media_link *link, u32 flags, + unsigned int notification) +{ + return 0; +} + +#endif /* CONFIG_MEDIA_CONTROLLER */ +#endif /* _V4L2_MC_H */ |