linux_dsm_epyc7002/include/media/cec-notifier.h
Hans Verkuil fbbd403b32 media: cec-notifier: add cec_notifier_parse_hdmi_phandle helper
Add helper function to parse the DT for the hdmi-phandle property
and return the corresponding struct device pointer.

It takes care to avoid increasing the device refcount since all
we need is the device pointer. This pointer is used in the
notifier list as a key, but it is never accessed by the CEC driver.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: Wen Yang <wen.yang99@zte.com.cn>
Acked-by: Wen Yang <wen.yang99@zte.com.cn>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-04-22 13:09:59 -04:00

175 lines
4.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* cec-notifier.h - notify CEC drivers of physical address changes
*
* Copyright 2016 Russell King <rmk+kernel@arm.linux.org.uk>
* Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*/
#ifndef LINUX_CEC_NOTIFIER_H
#define LINUX_CEC_NOTIFIER_H
#include <linux/err.h>
#include <media/cec.h>
struct device;
struct edid;
struct cec_adapter;
struct cec_notifier;
#if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
/**
* cec_notifier_get_conn - find or create a new cec_notifier for the given
* device and connector tuple.
* @dev: device that sends the events.
* @conn: the connector name from which the event occurs
*
* If a notifier for device @dev already exists, then increase the refcount
* and return that notifier.
*
* If it doesn't exist, then allocate a new notifier struct and return a
* pointer to that new struct.
*
* Return NULL if the memory could not be allocated.
*/
struct cec_notifier *cec_notifier_get_conn(struct device *dev,
const char *conn);
/**
* cec_notifier_put - decrease refcount and delete when the refcount reaches 0.
* @n: notifier
*/
void cec_notifier_put(struct cec_notifier *n);
/**
* cec_notifier_set_phys_addr - set a new physical address.
* @n: the CEC notifier
* @pa: the CEC physical address
*
* Set a new CEC physical address.
* Does nothing if @n == NULL.
*/
void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
/**
* cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
* @n: the CEC notifier
* @edid: the struct edid pointer
*
* Parses the EDID to obtain the new CEC physical address and set it.
* Does nothing if @n == NULL.
*/
void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
const struct edid *edid);
/**
* cec_notifier_register - register a callback with the notifier
* @n: the CEC notifier
* @adap: the CEC adapter, passed as argument to the callback function
* @callback: the callback function
*/
void cec_notifier_register(struct cec_notifier *n,
struct cec_adapter *adap,
void (*callback)(struct cec_adapter *adap, u16 pa));
/**
* cec_notifier_unregister - unregister the callback from the notifier.
* @n: the CEC notifier
*/
void cec_notifier_unregister(struct cec_notifier *n);
/**
* cec_register_cec_notifier - register the notifier with the cec adapter.
* @adap: the CEC adapter
* @notifier: the CEC notifier
*/
void cec_register_cec_notifier(struct cec_adapter *adap,
struct cec_notifier *notifier);
/**
* cec_notifier_parse_hdmi_phandle - find the hdmi device from "hdmi-phandle"
* @dev: the device with the "hdmi-phandle" device tree property
*
* Returns the device pointer referenced by the "hdmi-phandle" property.
* Note that the refcount of the returned device is not incremented.
* This device pointer is only used as a key value in the notifier
* list, but it is never accessed by the CEC driver.
*/
struct device *cec_notifier_parse_hdmi_phandle(struct device *dev);
#else
static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
const char *conn)
{
/* A non-NULL pointer is expected on success */
return (struct cec_notifier *)0xdeadfeed;
}
static inline void cec_notifier_put(struct cec_notifier *n)
{
}
static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
{
}
static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
const struct edid *edid)
{
}
static inline void cec_notifier_register(struct cec_notifier *n,
struct cec_adapter *adap,
void (*callback)(struct cec_adapter *adap, u16 pa))
{
}
static inline void cec_notifier_unregister(struct cec_notifier *n)
{
}
static inline void cec_register_cec_notifier(struct cec_adapter *adap,
struct cec_notifier *notifier)
{
}
static inline struct device *cec_notifier_parse_hdmi_phandle(struct device *dev)
{
return ERR_PTR(-ENODEV);
}
#endif
/**
* cec_notifier_get - find or create a new cec_notifier for the given device.
* @dev: device that sends the events.
*
* If a notifier for device @dev already exists, then increase the refcount
* and return that notifier.
*
* If it doesn't exist, then allocate a new notifier struct and return a
* pointer to that new struct.
*
* Return NULL if the memory could not be allocated.
*/
static inline struct cec_notifier *cec_notifier_get(struct device *dev)
{
return cec_notifier_get_conn(dev, NULL);
}
/**
* cec_notifier_phys_addr_invalidate() - set the physical address to INVALID
*
* @n: the CEC notifier
*
* This is a simple helper function to invalidate the physical
* address. Does nothing if @n == NULL.
*/
static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n)
{
cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID);
}
#endif