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_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 /** 91 * cec_notifier_parse_hdmi_phandle - find the hdmi device from "hdmi-phandle" 92 * @dev: the device with the "hdmi-phandle" device tree property 93 * 94 * Returns the device pointer referenced by the "hdmi-phandle" property. 95 * Note that the refcount of the returned device is not incremented. 96 * This device pointer is only used as a key value in the notifier 97 * list, but it is never accessed by the CEC driver. 98 */ 99 struct device *cec_notifier_parse_hdmi_phandle(struct device *dev); 100 101 #else 102 static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev, 103 const char *conn) 104 { 105 /* A non-NULL pointer is expected on success */ 106 return (struct cec_notifier *)0xdeadfeed; 107 } 108 109 static inline void cec_notifier_put(struct cec_notifier *n) 110 { 111 } 112 113 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa) 114 { 115 } 116 117 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n, 118 const struct edid *edid) 119 { 120 } 121 122 static inline void cec_notifier_register(struct cec_notifier *n, 123 struct cec_adapter *adap, 124 void (*callback)(struct cec_adapter *adap, u16 pa)) 125 { 126 } 127 128 static inline void cec_notifier_unregister(struct cec_notifier *n) 129 { 130 } 131 132 static inline void cec_register_cec_notifier(struct cec_adapter *adap, 133 struct cec_notifier *notifier) 134 { 135 } 136 137 static inline struct device *cec_notifier_parse_hdmi_phandle(struct device *dev) 138 { 139 return ERR_PTR(-ENODEV); 140 } 141 142 #endif 143 144 /** 145 * cec_notifier_get - find or create a new cec_notifier for the given device. 146 * @dev: device that sends the events. 147 * 148 * If a notifier for device @dev already exists, then increase the refcount 149 * and return that notifier. 150 * 151 * If it doesn't exist, then allocate a new notifier struct and return a 152 * pointer to that new struct. 153 * 154 * Return NULL if the memory could not be allocated. 155 */ 156 static inline struct cec_notifier *cec_notifier_get(struct device *dev) 157 { 158 return cec_notifier_get_conn(dev, NULL); 159 } 160 161 /** 162 * cec_notifier_phys_addr_invalidate() - set the physical address to INVALID 163 * 164 * @n: the CEC notifier 165 * 166 * This is a simple helper function to invalidate the physical 167 * address. Does nothing if @n == NULL. 168 */ 169 static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n) 170 { 171 cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID); 172 } 173 174 #endif 175