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/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_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_conn_register - find or create a new cec_notifier for the given
  41  * HDMI device and connector tuple.
  42  * @hdmi_dev: HDMI device that sends the events.
  43  * @conn_name: the connector name from which the event occurs. May be NULL
  44  * if there is always only one HDMI connector created by the HDMI device.
  45  * @conn_info: the connector info from which the event occurs (may be NULL)
  46  *
  47  * If a notifier for device @dev and connector @conn_name already exists, then
  48  * increase the refcount and return that notifier.
  49  *
  50  * If it doesn't exist, then allocate a new notifier struct and return a
  51  * pointer to that new struct.
  52  *
  53  * Return NULL if the memory could not be allocated.
  54  */
  55 struct cec_notifier *
  56 cec_notifier_conn_register(struct device *hdmi_dev, const char *conn_name,
  57                            const struct cec_connector_info *conn_info);
  58
  59 /**
  60  * cec_notifier_conn_unregister - decrease refcount and delete when the
  61  * refcount reaches 0.
  62  * @n: notifier. If NULL, then this function does nothing.
  63  */
  64 void cec_notifier_conn_unregister(struct cec_notifier *n);
  65
  66 /**
  67  * cec_notifier_cec_adap_register - find or create a new cec_notifier for the
  68  * given device.
  69  * @hdmi_dev: HDMI device that sends the events.
  70  * @conn_name: the connector name from which the event occurs. May be NULL
  71  * if there is always only one HDMI connector created by the HDMI device.
  72  * @adap: the cec adapter that registered this notifier.
  73  *
  74  * If a notifier for device @dev and connector @conn_name already exists, then
  75  * increase the refcount and return that notifier.
  76  *
  77  * If it doesn't exist, then allocate a new notifier struct and return a
  78  * pointer to that new struct.
  79  *
  80  * Return NULL if the memory could not be allocated.
  81  */
  82 struct cec_notifier *
  83 cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *conn_name,
  84                                struct cec_adapter *adap);
  85
  86 /**
  87  * cec_notifier_cec_adap_unregister - decrease refcount and delete when the
  88  * refcount reaches 0.
  89  * @n: notifier. If NULL, then this function does nothing.
  90  * @adap: the cec adapter that registered this notifier.
  91  */
  92 void cec_notifier_cec_adap_unregister(struct cec_notifier *n,
  93                                       struct cec_adapter *adap);
  94
  95 /**
  96  * cec_notifier_set_phys_addr - set a new physical address.
  97  * @n: the CEC notifier
  98  * @pa: the CEC physical address
  99  *
 100  * Set a new CEC physical address.
 101  * Does nothing if @n == NULL.
 102  */
 103 void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
 104
 105 /**
 106  * cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
 107  * @n: the CEC notifier
 108  * @edid: the struct edid pointer
 109  *
 110  * Parses the EDID to obtain the new CEC physical address and set it.
 111  * Does nothing if @n == NULL.
 112  */
 113 void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
 114                                           const struct edid *edid);
 115
 116 /**
 117  * cec_notifier_parse_hdmi_phandle - find the hdmi device from "hdmi-phandle"
 118  * @dev: the device with the "hdmi-phandle" device tree property
 119  *
 120  * Returns the device pointer referenced by the "hdmi-phandle" property.
 121  * Note that the refcount of the returned device is not incremented.
 122  * This device pointer is only used as a key value in the notifier
 123  * list, but it is never accessed by the CEC driver.
 124  */
 125 struct device *cec_notifier_parse_hdmi_phandle(struct device *dev);
 126
 127 #else
 128 static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
 129                                                          const char *conn)
 130 {
 131         /* A non-NULL pointer is expected on success */
 132         return (struct cec_notifier *)0xdeadfeed;
 133 }
 134
 135 static inline struct cec_notifier *
 136 cec_notifier_conn_register(struct device *hdmi_dev, const char *conn_name,
 137                            const struct cec_connector_info *conn_info)
 138 {
 139         /* A non-NULL pointer is expected on success */
 140         return (struct cec_notifier *)0xdeadfeed;
 141 }
 142
 143 static inline void cec_notifier_conn_unregister(struct cec_notifier *n)
 144 {
 145 }
 146
 147 static inline struct cec_notifier *
 148 cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *conn_name,
 149                                struct cec_adapter *adap)
 150 {
 151         /* A non-NULL pointer is expected on success */
 152         return (struct cec_notifier *)0xdeadfeed;
 153 }
 154
 155 static inline void cec_notifier_cec_adap_unregister(struct cec_notifier *n,
 156                                                     struct cec_adapter *adap)
 157 {
 158 }
 159
 160 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
 161 {
 162 }
 163
 164 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
 165                                                         const struct edid *edid)
 166 {
 167 }
 168
 169 static inline struct device *cec_notifier_parse_hdmi_phandle(struct device *dev)
 170 {
 171         return ERR_PTR(-ENODEV);
 172 }
 173
 174 #endif
 175
 176 /**
 177  * cec_notifier_phys_addr_invalidate() - set the physical address to INVALID
 178  *
 179  * @n: the CEC notifier
 180  *
 181  * This is a simple helper function to invalidate the physical
 182  * address. Does nothing if @n == NULL.
 183  */
 184 static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n)
 185 {
 186         cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID);
 187 }
 188
 189 #endif