1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * cec-pin.h - low-level CEC pin control |
4 | * |
5 | * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved. |
6 | */ |
7 | |
8 | #ifndef LINUX_CEC_PIN_H |
9 | #define LINUX_CEC_PIN_H |
10 | |
11 | #include <linux/types.h> |
12 | #include <media/cec.h> |
13 | |
14 | /** |
15 | * struct cec_pin_ops - low-level CEC pin operations |
16 | * @read: read the CEC pin. Returns > 0 if high, 0 if low, or an error |
17 | * if negative. |
18 | * @low: drive the CEC pin low. |
19 | * @high: stop driving the CEC pin. The pull-up will drive the pin |
20 | * high, unless someone else is driving the pin low. |
21 | * @enable_irq: optional, enable the interrupt to detect pin voltage changes. |
22 | * @disable_irq: optional, disable the interrupt. |
23 | * @free: optional. Free any allocated resources. Called when the |
24 | * adapter is deleted. |
25 | * @status: optional, log status information. |
26 | * @read_hpd: optional. Read the HPD pin. Returns > 0 if high, 0 if low or |
27 | * an error if negative. |
28 | * @read_5v: optional. Read the 5V pin. Returns > 0 if high, 0 if low or |
29 | * an error if negative. |
30 | * @received: optional. High-level CEC message callback. Allows the driver |
31 | * to process CEC messages. |
32 | * |
33 | * These operations (except for the @received op) are used by the |
34 | * cec pin framework to manipulate the CEC pin. |
35 | */ |
36 | struct cec_pin_ops { |
37 | int (*read)(struct cec_adapter *adap); |
38 | void (*low)(struct cec_adapter *adap); |
39 | void (*high)(struct cec_adapter *adap); |
40 | bool (*enable_irq)(struct cec_adapter *adap); |
41 | void (*disable_irq)(struct cec_adapter *adap); |
42 | void (*free)(struct cec_adapter *adap); |
43 | void (*status)(struct cec_adapter *adap, struct seq_file *file); |
44 | int (*read_hpd)(struct cec_adapter *adap); |
45 | int (*read_5v)(struct cec_adapter *adap); |
46 | |
47 | /* High-level CEC message callback */ |
48 | int (*received)(struct cec_adapter *adap, struct cec_msg *msg); |
49 | }; |
50 | |
51 | /** |
52 | * cec_pin_changed() - update pin state from interrupt |
53 | * |
54 | * @adap: pointer to the cec adapter |
55 | * @value: when true the pin is high, otherwise it is low |
56 | * |
57 | * If changes of the CEC voltage are detected via an interrupt, then |
58 | * cec_pin_changed is called from the interrupt with the new value. |
59 | */ |
60 | void cec_pin_changed(struct cec_adapter *adap, bool value); |
61 | |
62 | /** |
63 | * cec_pin_allocate_adapter() - allocate a pin-based cec adapter |
64 | * |
65 | * @pin_ops: low-level pin operations |
66 | * @priv: will be stored in adap->priv and can be used by the adapter ops. |
67 | * Use cec_get_drvdata(adap) to get the priv pointer. |
68 | * @name: the name of the CEC adapter. Note: this name will be copied. |
69 | * @caps: capabilities of the CEC adapter. This will be ORed with |
70 | * CEC_CAP_MONITOR_ALL and CEC_CAP_MONITOR_PIN. |
71 | * |
72 | * Allocate a cec adapter using the cec pin framework. |
73 | * |
74 | * Return: a pointer to the cec adapter or an error pointer |
75 | */ |
76 | struct cec_adapter *cec_pin_allocate_adapter(const struct cec_pin_ops *pin_ops, |
77 | void *priv, const char *name, u32 caps); |
78 | |
79 | #endif |
80 | |