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 <rmk+kernel@arm.linux.org.uk>
   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/types.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_get_conn - find or create a new cec_notifier for the given
  24  * device and connector tuple.
  25  * @dev: device that sends the events.
  26  * @conn: the connector name from which the event occurs
  27  *
  28  * If a notifier for device @dev already exists, then increase the refcount
  29  * and return that notifier.
  30  *
  31  * If it doesn't exist, then allocate a new notifier struct and return a
  32  * pointer to that new struct.
  33  *
  34  * Return NULL if the memory could not be allocated.
  35  */
  36 struct cec_notifier *cec_notifier_get_conn(struct device *dev,
  37                                            const char *conn);
  38
  39 /**
  40  * cec_notifier_put - decrease refcount and delete when the refcount reaches 0.
  41  * @n: notifier
  42  */
  43 void cec_notifier_put(struct cec_notifier *n);
  44
  45 /**
  46  * cec_notifier_set_phys_addr - set a new physical address.
  47  * @n: the CEC notifier
  48  * @pa: the CEC physical address
  49  *
  50  * Set a new CEC physical address.
  51  * Does nothing if @n == NULL.
  52  */
  53 void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
  54
  55 /**
  56  * cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
  57  * @n: the CEC notifier
  58  * @edid: the struct edid pointer
  59  *
  60  * Parses the EDID to obtain the new CEC physical address and set it.
  61  * Does nothing if @n == NULL.
  62  */
  63 void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
  64                                           const struct edid *edid);
  65
  66 /**
  67  * cec_notifier_register - register a callback with the notifier
  68  * @n: the CEC notifier
  69  * @adap: the CEC adapter, passed as argument to the callback function
  70  * @callback: the callback function
  71  */
  72 void cec_notifier_register(struct cec_notifier *n,
  73                            struct cec_adapter *adap,
  74                            void (*callback)(struct cec_adapter *adap, u16 pa));
  75
  76 /**
  77  * cec_notifier_unregister - unregister the callback from the notifier.
  78  * @n: the CEC notifier
  79  */
  80 void cec_notifier_unregister(struct cec_notifier *n);
  81
  82 /**
  83  * cec_register_cec_notifier - register the notifier with the cec adapter.
  84  * @adap: the CEC adapter
  85  * @notifier: the CEC notifier
  86  */
  87 void cec_register_cec_notifier(struct cec_adapter *adap,
  88                                struct cec_notifier *notifier);
  89
  90 #else
  91 static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
  92                                                          const char *conn)
  93 {
  94         /* A non-NULL pointer is expected on success */
  95         return (struct cec_notifier *)0xdeadfeed;
  96 }
  97
  98 static inline void cec_notifier_put(struct cec_notifier *n)
  99 {
 100 }
 101
 102 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
 103 {
 104 }
 105
 106 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
 107                                                         const struct edid *edid)
 108 {
 109 }
 110
 111 static inline void cec_notifier_register(struct cec_notifier *n,
 112                          struct cec_adapter *adap,
 113                          void (*callback)(struct cec_adapter *adap, u16 pa))
 114 {
 115 }
 116
 117 static inline void cec_notifier_unregister(struct cec_notifier *n)
 118 {
 119 }
 120
 121 static inline void cec_register_cec_notifier(struct cec_adapter *adap,
 122                                              struct cec_notifier *notifier)
 123 {
 124 }
 125 #endif
 126
 127 /**
 128  * cec_notifier_get - find or create a new cec_notifier for the given device.
 129  * @dev: device that sends the events.
 130  *
 131  * If a notifier for device @dev already exists, then increase the refcount
 132  * and return that notifier.
 133  *
 134  * If it doesn't exist, then allocate a new notifier struct and return a
 135  * pointer to that new struct.
 136  *
 137  * Return NULL if the memory could not be allocated.
 138  */
 139 static inline struct cec_notifier *cec_notifier_get(struct device *dev)
 140 {
 141         return cec_notifier_get_conn(dev, NULL);
 142 }
 143
 144 /**
 145  * cec_notifier_phys_addr_invalidate() - set the physical address to INVALID
 146  *
 147  * @n: the CEC notifier
 148  *
 149  * This is a simple helper function to invalidate the physical
 150  * address. Does nothing if @n == NULL.
 151  */
 152 static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n)
 153 {
 154         cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID);
 155 }
 156
 157 #endif