linux-sg2042/include/media/cec-edid.h

105 lines
3.5 KiB
C

/*
* cec-edid - HDMI Consumer Electronics Control & EDID helpers
*
* Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef _MEDIA_CEC_EDID_H
#define _MEDIA_CEC_EDID_H
#include <linux/types.h>
#define CEC_PHYS_ADDR_INVALID 0xffff
#define cec_phys_addr_exp(pa) \
((pa) >> 12), ((pa) >> 8) & 0xf, ((pa) >> 4) & 0xf, (pa) & 0xf
/**
* cec_get_edid_phys_addr() - find and return the physical address
*
* @edid: pointer to the EDID data
* @size: size in bytes of the EDID data
* @offset: If not %NULL then the location of the physical address
* bytes in the EDID will be returned here. This is set to 0
* if there is no physical address found.
*
* Return: the physical address or CEC_PHYS_ADDR_INVALID if there is none.
*/
u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size,
unsigned int *offset);
/**
* cec_set_edid_phys_addr() - find and set the physical address
*
* @edid: pointer to the EDID data
* @size: size in bytes of the EDID data
* @phys_addr: the new physical address
*
* This function finds the location of the physical address in the EDID
* and fills in the given physical address and updates the checksum
* at the end of the EDID block. It does nothing if the EDID doesn't
* contain a physical address.
*/
void cec_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr);
/**
* cec_phys_addr_for_input() - calculate the PA for an input
*
* @phys_addr: the physical address of the parent
* @input: the number of the input port, must be between 1 and 15
*
* This function calculates a new physical address based on the input
* port number. For example:
*
* PA = 0.0.0.0 and input = 2 becomes 2.0.0.0
*
* PA = 3.0.0.0 and input = 1 becomes 3.1.0.0
*
* PA = 3.2.1.0 and input = 5 becomes 3.2.1.5
*
* PA = 3.2.1.3 and input = 5 becomes f.f.f.f since it maxed out the depth.
*
* Return: the new physical address or CEC_PHYS_ADDR_INVALID.
*/
u16 cec_phys_addr_for_input(u16 phys_addr, u8 input);
/**
* cec_phys_addr_validate() - validate a physical address from an EDID
*
* @phys_addr: the physical address to validate
* @parent: if not %NULL, then this is filled with the parents PA.
* @port: if not %NULL, then this is filled with the input port.
*
* This validates a physical address as read from an EDID. If the
* PA is invalid (such as 1.0.1.0 since '0' is only allowed at the end),
* then it will return -EINVAL.
*
* The parent PA is passed into %parent and the input port is passed into
* %port. For example:
*
* PA = 0.0.0.0: has parent 0.0.0.0 and input port 0.
*
* PA = 1.0.0.0: has parent 0.0.0.0 and input port 1.
*
* PA = 3.2.0.0: has parent 3.0.0.0 and input port 2.
*
* PA = f.f.f.f: has parent f.f.f.f and input port 0.
*
* Return: 0 if the PA is valid, -EINVAL if not.
*/
int cec_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port);
#endif /* _MEDIA_CEC_EDID_H */