linux/include/media/v4l2-fwnode.h
Sakari Ailus da5c791cfc media: v4l2-fwnode: Document new usage patterns of v4l2_fwnode_endpoint_parse
Document that it is possible to provide defaults for multiple bus types to
v4l2_fwnode_endpoint_parse and v4l2_fwnode_endpoint_alloc_parse. Also
underline the fact that detecting the bus type without bus-type property
is only for the old drivers.

Also correct capitalisation of BT.656.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-10 14:28:50 +02:00

560 lines
21 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* V4L2 fwnode binding parsing library
*
* Copyright (c) 2016 Intel Corporation.
* Author: Sakari Ailus <sakari.ailus@linux.intel.com>
*
* Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
*
* Copyright (C) 2012 Renesas Electronics Corp.
* Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
*/
#ifndef _V4L2_FWNODE_H
#define _V4L2_FWNODE_H
#include <linux/errno.h>
#include <linux/fwnode.h>
#include <linux/list.h>
#include <linux/types.h>
#include <media/v4l2-mediabus.h>
struct fwnode_handle;
struct v4l2_async_notifier;
struct v4l2_async_subdev;
#define V4L2_FWNODE_CSI2_MAX_DATA_LANES 4
/**
* struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure
* @flags: media bus (V4L2_MBUS_*) flags
* @data_lanes: an array of physical data lane indexes
* @clock_lane: physical lane index of the clock lane
* @num_data_lanes: number of data lanes
* @lane_polarities: polarity of the lanes. The order is the same of
* the physical lanes.
*/
struct v4l2_fwnode_bus_mipi_csi2 {
unsigned int flags;
unsigned char data_lanes[V4L2_FWNODE_CSI2_MAX_DATA_LANES];
unsigned char clock_lane;
unsigned char num_data_lanes;
bool lane_polarities[1 + V4L2_FWNODE_CSI2_MAX_DATA_LANES];
};
/**
* struct v4l2_fwnode_bus_parallel - parallel data bus data structure
* @flags: media bus (V4L2_MBUS_*) flags
* @bus_width: bus width in bits
* @data_shift: data shift in bits
*/
struct v4l2_fwnode_bus_parallel {
unsigned int flags;
unsigned char bus_width;
unsigned char data_shift;
};
/**
* struct v4l2_fwnode_bus_mipi_csi1 - CSI-1/CCP2 data bus structure
* @clock_inv: polarity of clock/strobe signal
* false - not inverted, true - inverted
* @strobe: false - data/clock, true - data/strobe
* @lane_polarity: the polarities of the clock (index 0) and data lanes
* index (1)
* @data_lane: the number of the data lane
* @clock_lane: the number of the clock lane
*/
struct v4l2_fwnode_bus_mipi_csi1 {
unsigned char clock_inv:1;
unsigned char strobe:1;
bool lane_polarity[2];
unsigned char data_lane;
unsigned char clock_lane;
};
/**
* struct v4l2_fwnode_endpoint - the endpoint data structure
* @base: fwnode endpoint of the v4l2_fwnode
* @bus_type: bus type
* @bus: bus configuration data structure
* @bus.parallel: embedded &struct v4l2_fwnode_bus_parallel.
* Used if the bus is parallel.
* @bus.mipi_csi1: embedded &struct v4l2_fwnode_bus_mipi_csi1.
* Used if the bus is MIPI Alliance's Camera Serial
* Interface version 1 (MIPI CSI1) or Standard
* Mobile Imaging Architecture's Compact Camera Port 2
* (SMIA CCP2).
* @bus.mipi_csi2: embedded &struct v4l2_fwnode_bus_mipi_csi2.
* Used if the bus is MIPI Alliance's Camera Serial
* Interface version 2 (MIPI CSI2).
* @link_frequencies: array of supported link frequencies
* @nr_of_link_frequencies: number of elements in link_frequenccies array
*/
struct v4l2_fwnode_endpoint {
struct fwnode_endpoint base;
/*
* Fields below this line will be zeroed by
* v4l2_fwnode_endpoint_parse()
*/
enum v4l2_mbus_type bus_type;
struct {
struct v4l2_fwnode_bus_parallel parallel;
struct v4l2_fwnode_bus_mipi_csi1 mipi_csi1;
struct v4l2_fwnode_bus_mipi_csi2 mipi_csi2;
} bus;
u64 *link_frequencies;
unsigned int nr_of_link_frequencies;
};
/**
* V4L2_FWNODE_PROPERTY_UNSET - identify a non initialized property
*
* All properties in &struct v4l2_fwnode_device_properties are initialized
* to this value.
*/
#define V4L2_FWNODE_PROPERTY_UNSET (-1U)
/**
* enum v4l2_fwnode_orientation - possible device orientation
* @V4L2_FWNODE_ORIENTATION_FRONT: device installed on the front side
* @V4L2_FWNODE_ORIENTATION_BACK: device installed on the back side
* @V4L2_FWNODE_ORIENTATION_EXTERNAL: device externally located
*/
enum v4l2_fwnode_orientation {
V4L2_FWNODE_ORIENTATION_FRONT,
V4L2_FWNODE_ORIENTATION_BACK,
V4L2_FWNODE_ORIENTATION_EXTERNAL
};
/**
* struct v4l2_fwnode_device_properties - fwnode device properties
* @orientation: device orientation. See &enum v4l2_fwnode_orientation
* @rotation: device rotation
*/
struct v4l2_fwnode_device_properties {
enum v4l2_fwnode_orientation orientation;
unsigned int rotation;
};
/**
* struct v4l2_fwnode_link - a link between two endpoints
* @local_node: pointer to device_node of this endpoint
* @local_port: identifier of the port this endpoint belongs to
* @local_id: identifier of the id this endpoint belongs to
* @remote_node: pointer to device_node of the remote endpoint
* @remote_port: identifier of the port the remote endpoint belongs to
* @remote_id: identifier of the id the remote endpoint belongs to
*/
struct v4l2_fwnode_link {
struct fwnode_handle *local_node;
unsigned int local_port;
unsigned int local_id;
struct fwnode_handle *remote_node;
unsigned int remote_port;
unsigned int remote_id;
};
/**
* enum v4l2_connector_type - connector type
* @V4L2_CONN_UNKNOWN: unknown connector type, no V4L2 connector configuration
* @V4L2_CONN_COMPOSITE: analog composite connector
* @V4L2_CONN_SVIDEO: analog svideo connector
*/
enum v4l2_connector_type {
V4L2_CONN_UNKNOWN,
V4L2_CONN_COMPOSITE,
V4L2_CONN_SVIDEO,
};
/**
* struct v4l2_connector_link - connector link data structure
* @head: structure to be used to add the link to the
* &struct v4l2_fwnode_connector
* @fwnode_link: &struct v4l2_fwnode_link link between the connector and the
* device the connector belongs to.
*/
struct v4l2_connector_link {
struct list_head head;
struct v4l2_fwnode_link fwnode_link;
};
/**
* struct v4l2_fwnode_connector_analog - analog connector data structure
* @sdtv_stds: sdtv standards this connector supports, set to V4L2_STD_ALL
* if no restrictions are specified.
*/
struct v4l2_fwnode_connector_analog {
v4l2_std_id sdtv_stds;
};
/**
* struct v4l2_fwnode_connector - the connector data structure
* @name: the connector device name
* @label: optional connector label
* @type: connector type
* @links: list of all connector &struct v4l2_connector_link links
* @nr_of_links: total number of links
* @connector: connector configuration
* @connector.analog: analog connector configuration
* &struct v4l2_fwnode_connector_analog
*/
struct v4l2_fwnode_connector {
const char *name;
const char *label;
enum v4l2_connector_type type;
struct list_head links;
unsigned int nr_of_links;
union {
struct v4l2_fwnode_connector_analog analog;
/* future connectors */
} connector;
};
/**
* v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
* @fwnode: pointer to the endpoint's fwnode handle
* @vep: pointer to the V4L2 fwnode data structure
*
* This function parses the V4L2 fwnode endpoint specific parameters from the
* firmware. The caller is responsible for assigning @vep.bus_type to a valid
* media bus type. The caller may also set the default configuration for the
* endpoint --- a configuration that shall be in line with the DT binding
* documentation. Should a device support multiple bus types, the caller may
* call this function once the correct type is found --- with a default
* configuration valid for that type.
*
* It is also allowed to set @vep.bus_type to V4L2_MBUS_UNKNOWN. USING THIS
* FEATURE REQUIRES "bus-type" PROPERTY IN DT BINDINGS. For old drivers,
* guessing @vep.bus_type between CSI-2 D-PHY, parallel and BT.656 busses is
* supported. NEVER RELY ON GUESSING @vep.bus_type IN NEW DRIVERS!
*
* The function does not change the V4L2 fwnode endpoint state if it fails.
*
* NOTE: This function does not parse properties the size of which is variable
* without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in
* new drivers instead.
*
* Return: %0 on success or a negative error code on failure:
* %-ENOMEM on memory allocation failure
* %-EINVAL on parsing failure
* %-ENXIO on mismatching bus types
*/
int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode,
struct v4l2_fwnode_endpoint *vep);
/**
* v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by
* v4l2_fwnode_endpoint_alloc_parse()
* @vep: the V4L2 fwnode the resources of which are to be released
*
* It is safe to call this function with NULL argument or on a V4L2 fwnode the
* parsing of which failed.
*/
void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep);
/**
* v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties
* @fwnode: pointer to the endpoint's fwnode handle
* @vep: pointer to the V4L2 fwnode data structure
*
* This function parses the V4L2 fwnode endpoint specific parameters from the
* firmware. The caller is responsible for assigning @vep.bus_type to a valid
* media bus type. The caller may also set the default configuration for the
* endpoint --- a configuration that shall be in line with the DT binding
* documentation. Should a device support multiple bus types, the caller may
* call this function once the correct type is found --- with a default
* configuration valid for that type.
*
* It is also allowed to set @vep.bus_type to V4L2_MBUS_UNKNOWN. USING THIS
* FEATURE REQUIRES "bus-type" PROPERTY IN DT BINDINGS. For old drivers,
* guessing @vep.bus_type between CSI-2 D-PHY, parallel and BT.656 busses is
* supported. NEVER RELY ON GUESSING @vep.bus_type IN NEW DRIVERS!
*
* The function does not change the V4L2 fwnode endpoint state if it fails.
*
* v4l2_fwnode_endpoint_alloc_parse() has two important differences to
* v4l2_fwnode_endpoint_parse():
*
* 1. It also parses variable size data.
*
* 2. The memory it has allocated to store the variable size data must be freed
* using v4l2_fwnode_endpoint_free() when no longer needed.
*
* Return: %0 on success or a negative error code on failure:
* %-ENOMEM on memory allocation failure
* %-EINVAL on parsing failure
* %-ENXIO on mismatching bus types
*/
int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode,
struct v4l2_fwnode_endpoint *vep);
/**
* v4l2_fwnode_parse_link() - parse a link between two endpoints
* @fwnode: pointer to the endpoint's fwnode at the local end of the link
* @link: pointer to the V4L2 fwnode link data structure
*
* Fill the link structure with the local and remote nodes and port numbers.
* The local_node and remote_node fields are set to point to the local and
* remote port's parent nodes respectively (the port parent node being the
* parent node of the port node if that node isn't a 'ports' node, or the
* grand-parent node of the port node otherwise).
*
* A reference is taken to both the local and remote nodes, the caller must use
* v4l2_fwnode_put_link() to drop the references when done with the
* link.
*
* Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be
* found.
*/
int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
struct v4l2_fwnode_link *link);
/**
* v4l2_fwnode_put_link() - drop references to nodes in a link
* @link: pointer to the V4L2 fwnode link data structure
*
* Drop references to the local and remote nodes in the link. This function
* must be called on every link parsed with v4l2_fwnode_parse_link().
*/
void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link);
/**
* v4l2_fwnode_connector_free() - free the V4L2 connector acquired memory
* @connector: the V4L2 connector resources of which are to be released
*
* Free all allocated memory and put all links acquired by
* v4l2_fwnode_connector_parse() and v4l2_fwnode_connector_add_link().
*
* It is safe to call this function with NULL argument or on a V4L2 connector
* the parsing of which failed.
*/
void v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector);
/**
* v4l2_fwnode_connector_parse() - initialize the 'struct v4l2_fwnode_connector'
* @fwnode: pointer to the subdev endpoint's fwnode handle where the connector
* is connected to or to the connector endpoint fwnode handle.
* @connector: pointer to the V4L2 fwnode connector data structure
*
* Fill the &struct v4l2_fwnode_connector with the connector type, label and
* all &enum v4l2_connector_type specific connector data. The label is optional
* so it is set to %NULL if no one was found. The function initialize the links
* to zero. Adding links to the connector is done by calling
* v4l2_fwnode_connector_add_link().
*
* The memory allocated for the label must be freed when no longer needed.
* Freeing the memory is done by v4l2_fwnode_connector_free().
*
* Return:
* * %0 on success or a negative error code on failure:
* * %-EINVAL if @fwnode is invalid
* * %-ENOTCONN if connector type is unknown or connector device can't be found
*/
int v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode,
struct v4l2_fwnode_connector *connector);
/**
* v4l2_fwnode_connector_add_link - add a link between a connector node and
* a v4l2-subdev node.
* @fwnode: pointer to the subdev endpoint's fwnode handle where the connector
* is connected to
* @connector: pointer to the V4L2 fwnode connector data structure
*
* Add a new &struct v4l2_connector_link link to the
* &struct v4l2_fwnode_connector connector links list. The link local_node
* points to the connector node, the remote_node to the host v4l2 (sub)dev.
*
* The taken references to remote_node and local_node must be dropped and the
* allocated memory must be freed when no longer needed. Both is done by calling
* v4l2_fwnode_connector_free().
*
* Return:
* * %0 on success or a negative error code on failure:
* * %-EINVAL if @fwnode or @connector is invalid or @connector type is unknown
* * %-ENOMEM on link memory allocation failure
* * %-ENOTCONN if remote connector device can't be found
* * %-ENOLINK if link parsing between v4l2 (sub)dev and connector fails
*/
int v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode,
struct v4l2_fwnode_connector *connector);
/**
* v4l2_fwnode_device_parse() - parse fwnode device properties
* @dev: pointer to &struct device
* @props: pointer to &struct v4l2_fwnode_device_properties where to store the
* parsed properties values
*
* This function parses and validates the V4L2 fwnode device properties from the
* firmware interface, and fills the @struct v4l2_fwnode_device_properties
* provided by the caller.
*
* Return:
* % 0 on success
* %-EINVAL if a parsed property value is not valid
*/
int v4l2_fwnode_device_parse(struct device *dev,
struct v4l2_fwnode_device_properties *props);
/**
* typedef parse_endpoint_func - Driver's callback function to be called on
* each V4L2 fwnode endpoint.
*
* @dev: pointer to &struct device
* @vep: pointer to &struct v4l2_fwnode_endpoint
* @asd: pointer to &struct v4l2_async_subdev
*
* Return:
* * %0 on success
* * %-ENOTCONN if the endpoint is to be skipped but this
* should not be considered as an error
* * %-EINVAL if the endpoint configuration is invalid
*/
typedef int (*parse_endpoint_func)(struct device *dev,
struct v4l2_fwnode_endpoint *vep,
struct v4l2_async_subdev *asd);
/**
* v4l2_async_notifier_parse_fwnode_endpoints - Parse V4L2 fwnode endpoints in a
* device node
* @dev: the device the endpoints of which are to be parsed
* @notifier: notifier for @dev
* @asd_struct_size: size of the driver's async sub-device struct, including
* sizeof(struct v4l2_async_subdev). The &struct
* v4l2_async_subdev shall be the first member of
* the driver's async sub-device struct, i.e. both
* begin at the same memory address.
* @parse_endpoint: Driver's callback function called on each V4L2 fwnode
* endpoint. Optional.
*
* Parse the fwnode endpoints of the @dev device and populate the async sub-
* devices list in the notifier. The @parse_endpoint callback function is
* called for each endpoint with the corresponding async sub-device pointer to
* let the caller initialize the driver-specific part of the async sub-device
* structure.
*
* The notifier memory shall be zeroed before this function is called on the
* notifier.
*
* This function may not be called on a registered notifier and may be called on
* a notifier only once.
*
* The &struct v4l2_fwnode_endpoint passed to the callback function
* @parse_endpoint is released once the function is finished. If there is a need
* to retain that configuration, the user needs to allocate memory for it.
*
* Any notifier populated using this function must be released with a call to
* v4l2_async_notifier_cleanup() after it has been unregistered and the async
* sub-devices are no longer in use, even if the function returned an error.
*
* Return: %0 on success, including when no async sub-devices are found
* %-ENOMEM if memory allocation failed
* %-EINVAL if graph or endpoint parsing failed
* Other error codes as returned by @parse_endpoint
*/
int
v4l2_async_notifier_parse_fwnode_endpoints(struct device *dev,
struct v4l2_async_notifier *notifier,
size_t asd_struct_size,
parse_endpoint_func parse_endpoint);
/**
* v4l2_async_notifier_parse_fwnode_endpoints_by_port - Parse V4L2 fwnode
* endpoints of a port in a
* device node
* @dev: the device the endpoints of which are to be parsed
* @notifier: notifier for @dev
* @asd_struct_size: size of the driver's async sub-device struct, including
* sizeof(struct v4l2_async_subdev). The &struct
* v4l2_async_subdev shall be the first member of
* the driver's async sub-device struct, i.e. both
* begin at the same memory address.
* @port: port number where endpoints are to be parsed
* @parse_endpoint: Driver's callback function called on each V4L2 fwnode
* endpoint. Optional.
*
* This function is just like v4l2_async_notifier_parse_fwnode_endpoints() with
* the exception that it only parses endpoints in a given port. This is useful
* on devices that have both sinks and sources: the async sub-devices connected
* to sources have already been configured by another driver (on capture
* devices). In this case the driver must know which ports to parse.
*
* Parse the fwnode endpoints of the @dev device on a given @port and populate
* the async sub-devices list of the notifier. The @parse_endpoint callback
* function is called for each endpoint with the corresponding async sub-device
* pointer to let the caller initialize the driver-specific part of the async
* sub-device structure.
*
* The notifier memory shall be zeroed before this function is called on the
* notifier the first time.
*
* This function may not be called on a registered notifier and may be called on
* a notifier only once per port.
*
* The &struct v4l2_fwnode_endpoint passed to the callback function
* @parse_endpoint is released once the function is finished. If there is a need
* to retain that configuration, the user needs to allocate memory for it.
*
* Any notifier populated using this function must be released with a call to
* v4l2_async_notifier_cleanup() after it has been unregistered and the async
* sub-devices are no longer in use, even if the function returned an error.
*
* Return: %0 on success, including when no async sub-devices are found
* %-ENOMEM if memory allocation failed
* %-EINVAL if graph or endpoint parsing failed
* Other error codes as returned by @parse_endpoint
*/
int
v4l2_async_notifier_parse_fwnode_endpoints_by_port(struct device *dev,
struct v4l2_async_notifier *notifier,
size_t asd_struct_size,
unsigned int port,
parse_endpoint_func parse_endpoint);
/**
* v4l2_fwnode_reference_parse_sensor_common - parse common references on
* sensors for async sub-devices
* @dev: the device node the properties of which are parsed for references
* @notifier: the async notifier where the async subdevs will be added
*
* Parse common sensor properties for remote devices related to the
* sensor and set up async sub-devices for them.
*
* Any notifier populated using this function must be released with a call to
* v4l2_async_notifier_release() after it has been unregistered and the async
* sub-devices are no longer in use, even in the case the function returned an
* error.
*
* Return: 0 on success
* -ENOMEM if memory allocation failed
* -EINVAL if property parsing failed
*/
int v4l2_async_notifier_parse_fwnode_sensor_common(struct device *dev,
struct v4l2_async_notifier *notifier);
/* Helper macros to access the connector links. */
/** v4l2_connector_last_link - Helper macro to get the first
* &struct v4l2_fwnode_connector link
* @v4l2c: &struct v4l2_fwnode_connector owning the connector links
*
* This marco returns the first added &struct v4l2_connector_link connector
* link or @NULL if the connector has no links.
*/
#define v4l2_connector_first_link(v4l2c) \
list_first_entry_or_null(&(v4l2c)->links, \
struct v4l2_connector_link, head)
/** v4l2_connector_last_link - Helper macro to get the last
* &struct v4l2_fwnode_connector link
* @v4l2c: &struct v4l2_fwnode_connector owning the connector links
*
* This marco returns the last &struct v4l2_connector_link added connector link.
*/
#define v4l2_connector_last_link(v4l2c) \
list_last_entry(&(v4l2c)->links, struct v4l2_connector_link, head)
#endif /* _V4L2_FWNODE_H */