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_conn_register - find or create a new cec_notifier for the given
47 * HDMI device and connector tuple.
48 * @hdmi_dev: HDMI device that sends the events.
49 * @conn_name: the connector name from which the event occurs. May be NULL
50 * if there is always only one HDMI connector created by the HDMI device.
51 * @conn_info: the connector info from which the event occurs (may be NULL)
52 *
53 * If a notifier for device @dev and connector @conn_name already exists, then
54 * increase the refcount and return that notifier.
55 *
56 * If it doesn't exist, then allocate a new notifier struct and return a
57 * pointer to that new struct.
58 *
59 * Return NULL if the memory could not be allocated.
60 */
61 struct cec_notifier *
62 cec_notifier_conn_register(struct device *hdmi_dev, const char *conn_name,
63 const struct cec_connector_info *conn_info);
64
65 /**
66 * cec_notifier_conn_unregister - decrease refcount and delete when the
67 * refcount reaches 0.
68 * @n: notifier. If NULL, then this function does nothing.
69 */
70 void cec_notifier_conn_unregister(struct cec_notifier *n);
71
72 /**
73 * cec_notifier_cec_adap_register - find or create a new cec_notifier for the
74 * given device.
75 * @hdmi_dev: HDMI device that sends the events.
76 * @conn_name: the connector name from which the event occurs. May be NULL
77 * if there is always only one HDMI connector created by the HDMI device.
78 * @adap: the cec adapter that registered this notifier.
79 *
80 * If a notifier for device @dev and connector @conn_name already exists, then
81 * increase the refcount and return that notifier.
82 *
83 * If it doesn't exist, then allocate a new notifier struct and return a
84 * pointer to that new struct.
85 *
86 * Return NULL if the memory could not be allocated.
87 */
88 struct cec_notifier *
89 cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *conn_name,
90 struct cec_adapter *adap);
91
92 /**
93 * cec_notifier_cec_adap_unregister - decrease refcount and delete when the
94 * refcount reaches 0.
95 * @n: notifier. If NULL, then this function does nothing.
96 */
97 void cec_notifier_cec_adap_unregister(struct cec_notifier *n);
98
99 /**
100 * cec_notifier_set_phys_addr - set a new physical address.
101 * @n: the CEC notifier
102 * @pa: the CEC physical address
103 *
104 * Set a new CEC physical address.
105 * Does nothing if @n == NULL.
106 */
107 void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
108
109 /**
110 * cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
111 * @n: the CEC notifier
112 * @edid: the struct edid pointer
113 *
114 * Parses the EDID to obtain the new CEC physical address and set it.
115 * Does nothing if @n == NULL.
116 */
117 void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
118 const struct edid *edid);
119
120 /**
121 * cec_notifier_parse_hdmi_phandle - find the hdmi device from "hdmi-phandle"
122 * @dev: the device with the "hdmi-phandle" device tree property
123 *
124 * Returns the device pointer referenced by the "hdmi-phandle" property.
125 * Note that the refcount of the returned device is not incremented.
126 * This device pointer is only used as a key value in the notifier
127 * list, but it is never accessed by the CEC driver.
128 */
129 struct device *cec_notifier_parse_hdmi_phandle(struct device *dev);
130
131 #else
132 static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
133 const char *conn)
134 {
135 /* A non-NULL pointer is expected on success */
136 return (struct cec_notifier *)0xdeadfeed;
137 }
138
139 static inline void cec_notifier_put(struct cec_notifier *n)
140 {
141 }
142
143 static inline struct cec_notifier *
144 cec_notifier_conn_register(struct device *hdmi_dev, const char *conn_name,
145 const struct cec_connector_info *conn_info)
146 {
147 /* A non-NULL pointer is expected on success */
148 return (struct cec_notifier *)0xdeadfeed;
149 }
150
151 static inline void cec_notifier_conn_unregister(struct cec_notifier *n)
152 {
153 }
154
155 static inline struct cec_notifier *
156 cec_notifier_cec_adap_register(struct device *hdmi_dev, const char *conn_name,
157 struct cec_adapter *adap)
158 {
159 /* A non-NULL pointer is expected on success */
160 return (struct cec_notifier *)0xdeadfeed;
161 }
162
163 static inline void cec_notifier_cec_adap_unregister(struct cec_notifier *n)
164 {
165 }
166
167 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
168 {
169 }
170
171 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
172 const struct edid *edid)
173 {
174 }
175
176 static inline struct device *cec_notifier_parse_hdmi_phandle(struct device *dev)
177 {
178 return ERR_PTR(-ENODEV);
179 }
180
181 #endif
182
183 /**
184 * cec_notifier_get - find or create a new cec_notifier for the given device.
185 * @dev: device that sends the events.
186 *
187 * If a notifier for device @dev already exists, then increase the refcount
188 * and return that notifier.
189 *
190 * If it doesn't exist, then allocate a new notifier struct and return a
191 * pointer to that new struct.
192 *
193 * Return NULL if the memory could not be allocated.
194 */
195 static inline struct cec_notifier *cec_notifier_get(struct device *dev)
196 {
197 return cec_notifier_get_conn(dev, NULL);
198 }
199
200 /**
201 * cec_notifier_phys_addr_invalidate() - set the physical address to INVALID
202 *
203 * @n: the CEC notifier
204 *
205 * This is a simple helper function to invalidate the physical
206 * address. Does nothing if @n == NULL.
207 */
208 static inline void cec_notifier_phys_addr_invalidate(struct cec_notifier *n)
209 {
210 cec_notifier_set_phys_addr(n, CEC_PHYS_ADDR_INVALID);
211 }
212
213 #endif