2.23. V4L2 fwnode kAPI¶
- 
struct v4l2_fwnode_endpoint¶
- the endpoint data structure 
Definition:
struct v4l2_fwnode_endpoint {
    struct fwnode_endpoint base;
    enum v4l2_mbus_type bus_type;
    struct {
        struct v4l2_mbus_config_parallel parallel;
        struct v4l2_mbus_config_mipi_csi1 mipi_csi1;
        struct v4l2_mbus_config_mipi_csi2 mipi_csi2;
    } bus;
    u64 *link_frequencies;
    unsigned int nr_of_link_frequencies;
};
Members
- base
- fwnode endpoint of the v4l2_fwnode 
- bus_type
- bus type 
- bus
- bus configuration data structure 
- bus.parallel
- embedded - struct v4l2_mbus_config_parallel. Used if the bus is parallel.
- bus.mipi_csi1
- embedded - struct v4l2_mbus_config_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_mbus_config_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 
- 
V4L2_FWNODE_PROPERTY_UNSET¶
V4L2_FWNODE_PROPERTY_UNSET
identify a non initialized property
Description
All properties in
struct v4l2_fwnode_device_propertiesare initialized to this value.
- 
enum v4l2_fwnode_orientation¶
- possible device orientation 
Constants
- 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 
- 
struct v4l2_fwnode_device_properties¶
- fwnode device properties 
Definition:
struct v4l2_fwnode_device_properties {
    enum v4l2_fwnode_orientation orientation;
    unsigned int rotation;
};
Members
- orientation
- device orientation. See - enum v4l2_fwnode_orientation
- rotation
- device rotation 
- 
struct v4l2_fwnode_link¶
- a link between two endpoints 
Definition:
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;
};
Members
- 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 
- 
enum v4l2_connector_type¶
- connector type 
Constants
- V4L2_CONN_UNKNOWN
- unknown connector type, no V4L2 connector configuration 
- V4L2_CONN_COMPOSITE
- analog composite connector 
- V4L2_CONN_SVIDEO
- analog svideo connector 
- 
struct v4l2_connector_link¶
- connector link data structure 
Definition:
struct v4l2_connector_link {
    struct list_head head;
    struct v4l2_fwnode_link fwnode_link;
};
Members
- head
- structure to be used to add the link to the - struct v4l2_fwnode_connector
- fwnode_link
- struct v4l2_fwnode_linklink between the connector and the device the connector belongs to.
- 
struct v4l2_fwnode_connector_analog¶
- analog connector data structure 
Definition:
struct v4l2_fwnode_connector_analog {
    v4l2_std_id sdtv_stds;
};
Members
- sdtv_stds
- sdtv standards this connector supports, set to V4L2_STD_ALL if no restrictions are specified. 
- 
struct v4l2_fwnode_connector¶
- the connector data structure 
Definition:
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;
    } connector;
};
Members
- name
- the connector device name 
- label
- optional connector label 
- type
- connector type 
- links
- list of all connector - struct v4l2_connector_linklinks
- nr_of_links
- total number of links 
- connector
- connector configuration 
- connector.analog
- analog connector configuration - struct v4l2_fwnode_connector_analog
- 
enum v4l2_fwnode_bus_type¶
- Video bus types defined by firmware properties 
Constants
- V4L2_FWNODE_BUS_TYPE_GUESS
- Default value if no bus-type fwnode property 
- V4L2_FWNODE_BUS_TYPE_CSI2_CPHY
- MIPI CSI-2 bus, C-PHY physical layer 
- V4L2_FWNODE_BUS_TYPE_CSI1
- MIPI CSI-1 bus 
- V4L2_FWNODE_BUS_TYPE_CCP2
- SMIA Compact Camera Port 2 bus 
- V4L2_FWNODE_BUS_TYPE_CSI2_DPHY
- MIPI CSI-2 bus, D-PHY physical layer 
- V4L2_FWNODE_BUS_TYPE_PARALLEL
- Camera Parallel Interface bus 
- V4L2_FWNODE_BUS_TYPE_BT656
- BT.656 video format bus-type 
- V4L2_FWNODE_BUS_TYPE_DPI
- Video Parallel Interface bus 
- NR_OF_V4L2_FWNODE_BUS_TYPE
- Number of bus-types 
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int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)¶
- parse all fwnode node properties 
Parameters
- struct fwnode_handle *fwnode
- pointer to the endpoint’s fwnode handle 
- struct v4l2_fwnode_endpoint *vep
- pointer to the V4L2 fwnode data structure 
Description
This function parses the V4L2 fwnode endpoint specific parameters from the
firmware. There are two ways to use this function, either by letting it
obtain the type of the bus (by setting the vep.bus_type field to
V4L2_MBUS_UNKNOWN) or specifying the bus type explicitly to one of the enum
v4l2_mbus_type types.
When vep.bus_type is V4L2_MBUS_UNKNOWN, the function will use the “bus-type” property to determine the type when it is available. The caller is responsible for validating the contents of vep.bus_type field after the call returns.
As a deprecated functionality to support older DT bindings without “bus-type” property for devices that support multiple types, if the “bus-type” property does not exist, the function will attempt to guess the type based on the endpoint properties available. NEVER RELY ON GUESSING THE BUS TYPE IN NEW DRIVERS OR BINDINGS.
It is also possible to set vep.bus_type corresponding to an actual bus. In this case the function will only attempt to parse properties related to this bus, and it will return an error if the value of the “bus-type” property corresponds to a different bus.
The caller is required to initialise all fields of vep, either with explicitly values, or by zeroing them.
The function does not change the V4L2 fwnode endpoint state if it fails.
NOTE
This function does not parse “link-frequencies” property as its size is
not known in advance. Please use v4l2_fwnode_endpoint_alloc_parse() if you
need properties of variable size.
Return
- 0on success or a negative error code on failure:
- -ENOMEMon memory allocation failure- -EINVALon parsing failure- -ENXIOon mismatching bus types
- 
void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep)¶
- free the V4L2 fwnode acquired by - v4l2_fwnode_endpoint_alloc_parse()
Parameters
- struct v4l2_fwnode_endpoint *vep
- the V4L2 fwnode the resources of which are to be released 
Description
It is safe to call this function with NULL argument or on a V4L2 fwnode the parsing of which failed.
- 
int v4l2_fwnode_endpoint_alloc_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep)¶
- parse all fwnode node properties 
Parameters
- struct fwnode_handle *fwnode
- pointer to the endpoint’s fwnode handle 
- struct v4l2_fwnode_endpoint *vep
- pointer to the V4L2 fwnode data structure 
Description
This function parses the V4L2 fwnode endpoint specific parameters from the
firmware. There are two ways to use this function, either by letting it
obtain the type of the bus (by setting the vep.bus_type field to
V4L2_MBUS_UNKNOWN) or specifying the bus type explicitly to one of the enum
v4l2_mbus_type types.
When vep.bus_type is V4L2_MBUS_UNKNOWN, the function will use the “bus-type” property to determine the type when it is available. The caller is responsible for validating the contents of vep.bus_type field after the call returns.
As a deprecated functionality to support older DT bindings without “bus-type” property for devices that support multiple types, if the “bus-type” property does not exist, the function will attempt to guess the type based on the endpoint properties available. NEVER RELY ON GUESSING THE BUS TYPE IN NEW DRIVERS OR BINDINGS.
It is also possible to set vep.bus_type corresponding to an actual bus. In this case the function will only attempt to parse properties related to this bus, and it will return an error if the value of the “bus-type” property corresponds to a different bus.
The caller is required to initialise all fields of vep, either with explicitly values, or by zeroing them.
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():
- It also parses variable size data. 
- The memory it has allocated to store the variable size data must be freed using - v4l2_fwnode_endpoint_free()when no longer needed.
Return
- 0on success or a negative error code on failure:
- -ENOMEMon memory allocation failure- -EINVALon parsing failure- -ENXIOon mismatching bus types
- 
int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, struct v4l2_fwnode_link *link)¶
- parse a link between two endpoints 
Parameters
- struct fwnode_handle *fwnode
- pointer to the endpoint’s fwnode at the local end of the link 
- struct v4l2_fwnode_link *link
- pointer to the V4L2 fwnode link data structure 
Description
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.
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void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link)¶
- drop references to nodes in a link 
Parameters
- struct v4l2_fwnode_link *link
- pointer to the V4L2 fwnode link data structure 
Description
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().
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void v4l2_fwnode_connector_free(struct v4l2_fwnode_connector *connector)¶
- free the V4L2 connector acquired memory 
Parameters
- struct v4l2_fwnode_connector *connector
- the V4L2 connector resources of which are to be released 
Description
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.
- 
int v4l2_fwnode_connector_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_connector *connector)¶
- initialize the ‘ - struct v4l2_fwnode_connector’
Parameters
- struct fwnode_handle *fwnode
- pointer to the subdev endpoint’s fwnode handle where the connector is connected to or to the connector endpoint fwnode handle. 
- struct v4l2_fwnode_connector *connector
- pointer to the V4L2 fwnode connector data structure 
Description
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
- 0on success or a negative error code on failure:
- -EINVALif fwnode is invalid
- -ENOTCONNif connector type is unknown or connector device can’t be found
- 
int v4l2_fwnode_connector_add_link(struct fwnode_handle *fwnode, struct v4l2_fwnode_connector *connector)¶
- add a link between a connector node and a v4l2-subdev node. 
Parameters
- struct fwnode_handle *fwnode
- pointer to the subdev endpoint’s fwnode handle where the connector is connected to 
- struct v4l2_fwnode_connector *connector
- pointer to the V4L2 fwnode connector data structure 
Description
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
- 0on success or a negative error code on failure:
- -EINVALif fwnode or connector is invalid or connector type is unknown
- -ENOMEMon link memory allocation failure
- -ENOTCONNif remote connector device can’t be found
- -ENOLINKif link parsing between v4l2 (sub)dev and connector fails
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int v4l2_fwnode_device_parse(struct device *dev, struct v4l2_fwnode_device_properties *props)¶
- parse fwnode device properties 
Parameters
- struct device *dev
- pointer to - struct device
- struct v4l2_fwnode_device_properties *props
- pointer to - struct v4l2_fwnode_device_propertieswhere to store the parsed properties values
Description
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
-EINVALif a parsed property value is not valid