1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * m52790 i2c ivtv driver.
4 * Copyright (C) 2007  Hans Verkuil
5 *
6 * A/V source switching Mitsubishi M52790SP/FP
7 */
8
9
10#include <linux/module.h>
11#include <linux/types.h>
12#include <linux/slab.h>
13#include <linux/ioctl.h>
14#include <linux/uaccess.h>
15#include <linux/i2c.h>
16#include <linux/videodev2.h>
17#include <media/i2c/m52790.h>
18#include <media/v4l2-device.h>
19
20MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
21MODULE_AUTHOR("Hans Verkuil");
22MODULE_LICENSE("GPL");
23
24
25struct m52790_state {
26	struct v4l2_subdev sd;
27	u16 input;
28	u16 output;
29};
30
31static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
32{
33	return container_of(sd, struct m52790_state, sd);
34}
35
36/* ----------------------------------------------------------------------- */
37
38static int m52790_write(struct v4l2_subdev *sd)
39{
40	struct m52790_state *state = to_state(sd);
41	struct i2c_client *client = v4l2_get_subdevdata(sd);
42
43	u8 sw1 = (state->input | state->output) & 0xff;
44	u8 sw2 = (state->input | state->output) >> 8;
45
46	return i2c_smbus_write_byte_data(client, sw1, sw2);
47}
48
49/* Note: audio and video are linked and cannot be switched separately.
50   So audio and video routing commands are identical for this chip.
51   In theory the video amplifier and audio modes could be handled
52   separately for the output, but that seems to be overkill right now.
53   The same holds for implementing an audio mute control, this is now
54   part of the audio output routing. The normal case is that another
55   chip takes care of the actual muting so making it part of the
56   output routing seems to be the right thing to do for now. */
57static int m52790_s_routing(struct v4l2_subdev *sd,
58			    u32 input, u32 output, u32 config)
59{
60	struct m52790_state *state = to_state(sd);
61
62	state->input = input;
63	state->output = output;
64	m52790_write(sd);
65	return 0;
66}
67
68#ifdef CONFIG_VIDEO_ADV_DEBUG
69static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
70{
71	struct m52790_state *state = to_state(sd);
72
73	if (reg->reg != 0)
74		return -EINVAL;
75	reg->size = 1;
76	reg->val = state->input | state->output;
77	return 0;
78}
79
80static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
81{
82	struct m52790_state *state = to_state(sd);
83
84	if (reg->reg != 0)
85		return -EINVAL;
86	state->input = reg->val & 0x0303;
87	state->output = reg->val & ~0x0303;
88	m52790_write(sd);
89	return 0;
90}
91#endif
92
93static int m52790_log_status(struct v4l2_subdev *sd)
94{
95	struct m52790_state *state = to_state(sd);
96
97	v4l2_info(sd, "Switch 1: %02x\n",
98			(state->input | state->output) & 0xff);
99	v4l2_info(sd, "Switch 2: %02x\n",
100			(state->input | state->output) >> 8);
101	return 0;
102}
103
104/* ----------------------------------------------------------------------- */
105
106static const struct v4l2_subdev_core_ops m52790_core_ops = {
107	.log_status = m52790_log_status,
108#ifdef CONFIG_VIDEO_ADV_DEBUG
109	.g_register = m52790_g_register,
110	.s_register = m52790_s_register,
111#endif
112};
113
114static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
115	.s_routing = m52790_s_routing,
116};
117
118static const struct v4l2_subdev_video_ops m52790_video_ops = {
119	.s_routing = m52790_s_routing,
120};
121
122static const struct v4l2_subdev_ops m52790_ops = {
123	.core = &m52790_core_ops,
124	.audio = &m52790_audio_ops,
125	.video = &m52790_video_ops,
126};
127
128/* ----------------------------------------------------------------------- */
129
130/* i2c implementation */
131
132static int m52790_probe(struct i2c_client *client)
133{
134	struct m52790_state *state;
135	struct v4l2_subdev *sd;
136
137	/* Check if the adapter supports the needed features */
138	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
139		return -EIO;
140
141	v4l_info(client, "chip found @ 0x%x (%s)\n",
142			client->addr << 1, client->adapter->name);
143
144	state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
145	if (state == NULL)
146		return -ENOMEM;
147
148	sd = &state->sd;
149	v4l2_i2c_subdev_init(sd, client, &m52790_ops);
150	state->input = M52790_IN_TUNER;
151	state->output = M52790_OUT_STEREO;
152	m52790_write(sd);
153	return 0;
154}
155
156static void m52790_remove(struct i2c_client *client)
157{
158	struct v4l2_subdev *sd = i2c_get_clientdata(client);
159
160	v4l2_device_unregister_subdev(sd);
161}
162
163/* ----------------------------------------------------------------------- */
164
165static const struct i2c_device_id m52790_id[] = {
166	{ "m52790", 0 },
167	{ }
168};
169MODULE_DEVICE_TABLE(i2c, m52790_id);
170
171static struct i2c_driver m52790_driver = {
172	.driver = {
173		.name	= "m52790",
174	},
175	.probe		= m52790_probe,
176	.remove		= m52790_remove,
177	.id_table	= m52790_id,
178};
179
180module_i2c_driver(m52790_driver);
181