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
  15 struct device;
  16 struct edid;
  17 struct cec_adapter;
  18 struct 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  */
  38 struct cec_notifier *
  39 cec_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  */
  47 void 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  */
  65 struct cec_notifier *
  66 cec_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  */
  75 void 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  */
  86 void 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  */
  96 void 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  */
 108 struct device *cec_notifier_parse_hdmi_phandle(struct device *dev);
 109
 110 #else
 111
 112 static inline struct cec_notifier *
 113 cec_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
 120 static inline void cec_notifier_conn_unregister(struct cec_notifier *n)
 121 {
 122 }
 123
 124 static inline struct cec_notifier *
 125 cec_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
 132 static inline void cec_notifier_cec_adap_unregister(struct cec_notifier *n,
 133                                                     struct cec_adapter *adap)
 134 {
 135 }
 136
 137 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
 138 {
 139 }
 140
 141 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
 142                                                         const struct edid *edid)
 143 {
 144 }
 145
 146 static 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  */
 161 static 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