LXR linux/include/media/cec-notifier.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * cec-notifier.h - notify CEC drivers of physical address changes
   4 *
   5 * Copyright 2016 Russell King.
   6 * Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   7 */
   8
   9#ifndef LINUX_CEC_NOTIFIER_H
  10#define LINUX_CEC_NOTIFIER_H
  11
  12#include <linux/err.h>
  13#include <media/cec.h>
  14
  15struct device;
  16struct edid;
  17struct cec_adapter;
  18struct cec_notifier;
  19
  20#if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
  21
  22/**
  23 * cec_notifier_conn_register - find or create a new cec_notifier for the given
  24 * HDMI device and connector tuple.
  25 * @hdmi_dev: HDMI device that sends the events.
  26 * @port_name: the connector name from which the event occurs. May be NULL
  27 * if there is always only one HDMI connector created by the HDMI device.
  28 * @conn_info: the connector info from which the event occurs (may be NULL)
  29 *
  30 * If a notifier for device @dev and connector @port_name already exists, then
  31 * increase the refcount and return that notifier.
  32 *
  33 * If it doesn't exist, then allocate a new notifier struct and return a
  34 * pointer to that new struct.
  35 *
  36 * Return NULL if the memory could not be allocated.
  37 */
  38struct cec_notifier *
  39cec_notifier_conn_register(struct device *hdmi_dev, const char *port_name,
  40                           const struct cec_connector_info *conn_info);
  41
  42/**
  43 * cec_notifier_conn_unregister - decrease refcount and delete when the
  44 * refcount reaches 0.
  45 * @n: notifier. If NULL, then this function does nothing.
  46 */
  47void cec_notifier_conn_unregister(struct cec_notifier *n);
  48
  49/**
  50 * cec_notifier_cec_adap_register - find or create a new cec_notifier for the
  51 * given device.
  52 * @hdmi_dev: HDMI device that sends the events.
  53 * @port_name: the connector name from which the event occurs. May be NULL
  54 * if there is always only one HDMI connector created by the HDMI device.
  55 * @adap: the cec adapter that registered this notifier.
  56 *
  57 * If a notifier for device @dev and connector @port_name already exists, then
  58 * increase the refcount and return that notifier.
  59 *
  60 * If it doesn't exist, then allocate a new notifier struct and return a
  61 * pointer to that new struct.
  62 *
  63 * Return NULL if the memory could not be allocated.
  64 */
  65struct cec_notifier *
  66cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *port_name,
  67                               struct cec_adapter *adap);
  68
  69/**
  70 * cec_notifier_cec_adap_unregister - decrease refcount and delete when the
  71 * refcount reaches 0.
  72 * @n: notifier. If NULL, then this function does nothing.
  73 * @adap: the cec adapter that registered this notifier.
  74 */
  75void cec_notifier_cec_adap_unregister(struct cec_notifier *n,
  76                                      struct cec_adapter *adap);
  77
  78/**
  79 * cec_notifier_set_phys_addr - set a new physical address.
  80 * @n: the CEC notifier
  81 * @pa: the CEC physical address
  82 *
  83 * Set a new CEC physical address.
  84 * Does nothing if @n == NULL.
  85 */
  86void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
  87
  88/**
  89 * cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
  90 * @n: the CEC notifier
  91 * @edid: the struct edid pointer
  92 *
  93 * Parses the EDID to obtain the new CEC physical address and set it.
  94 * Does nothing if @n == NULL.
  95 */
  96void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
  97                                          const struct edid *edid);
  98
  99/**
 100 * cec_notifier_parse_hdmi_phandle - find the hdmi device from "hdmi-phandle"
 101 * @dev: the device with the "hdmi-phandle" device tree property
 102 *
 103 * Returns the device pointer referenced by the "hdmi-phandle" property.
 104 * Note that the refcount of the returned device is not incremented.
 105 * This device pointer is only used as a key value in the notifier
 106 * list, but it is never accessed by the CEC driver.
 107 */
 108struct device *cec_notifier_parse_hdmi_phandle(struct device *dev);
 109
 110#else
 111
 112static inline struct cec_notifier *
 113cec_notifier_conn_register(struct device *hdmi_dev, const char *port_name,
 114                           const struct cec_connector_info *conn_info)
 115{
 116        /* A non-NULL pointer is expected on success */
 117        return (struct cec_notifier *)0xdeadfeed;
 118}
 119
 120static inline void cec_notifier_conn_unregister(struct cec_notifier *n)
 121{
 122}
 123
 124static inline struct cec_notifier *
 125cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *port_name,
 126                               struct cec_adapter *adap)
 127{
 128        /* A non-NULL pointer is expected on success */
 129        return (struct cec_notifier *)0xdeadfeed;
 130}
 131
 132static inline void cec_notifier_cec_adap_unregister(struct cec_notifier *n,
 133                                                    struct cec_adapter *adap)
 134{
 135}
 136
 137static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
 138{
 139}
 140
 141static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
 142                                                        const struct edid *edid)
 143{
 144}
 145
 146static inline struct device *cec_notifier_parse_hdmi_phandle(struct device *dev)
 147{
 148        return ERR_PTR(-ENODEV);
 149}
 150
 151#endif
 152
 153/**
 154 * cec_notifier_phys_addr_invalidate() - set the physical address to INVALID
 155 *
 156 * @n: the CEC notifier
 157 *
 158 * This is a simple helper function to invalidate the physical
 159 * address. Does nothing if @n == NULL.
 160 */
 161static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n)
 162{
 163        cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID);
 164}
 165
 166#endif
 167