xref: /openbmc/linux/drivers/media/i2c/m52790.c (revision 82e6fdd6)
1 /*
2  * m52790 i2c ivtv driver.
3  * Copyright (C) 2007  Hans Verkuil
4  *
5  * A/V source switching Mitsubishi M52790SP/FP
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 
19 #include <linux/module.h>
20 #include <linux/types.h>
21 #include <linux/slab.h>
22 #include <linux/ioctl.h>
23 #include <linux/uaccess.h>
24 #include <linux/i2c.h>
25 #include <linux/videodev2.h>
26 #include <media/i2c/m52790.h>
27 #include <media/v4l2-device.h>
28 
29 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
30 MODULE_AUTHOR("Hans Verkuil");
31 MODULE_LICENSE("GPL");
32 
33 
34 struct m52790_state {
35 	struct v4l2_subdev sd;
36 	u16 input;
37 	u16 output;
38 };
39 
40 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
41 {
42 	return container_of(sd, struct m52790_state, sd);
43 }
44 
45 /* ----------------------------------------------------------------------- */
46 
47 static int m52790_write(struct v4l2_subdev *sd)
48 {
49 	struct m52790_state *state = to_state(sd);
50 	struct i2c_client *client = v4l2_get_subdevdata(sd);
51 
52 	u8 sw1 = (state->input | state->output) & 0xff;
53 	u8 sw2 = (state->input | state->output) >> 8;
54 
55 	return i2c_smbus_write_byte_data(client, sw1, sw2);
56 }
57 
58 /* Note: audio and video are linked and cannot be switched separately.
59    So audio and video routing commands are identical for this chip.
60    In theory the video amplifier and audio modes could be handled
61    separately for the output, but that seems to be overkill right now.
62    The same holds for implementing an audio mute control, this is now
63    part of the audio output routing. The normal case is that another
64    chip takes care of the actual muting so making it part of the
65    output routing seems to be the right thing to do for now. */
66 static int m52790_s_routing(struct v4l2_subdev *sd,
67 			    u32 input, u32 output, u32 config)
68 {
69 	struct m52790_state *state = to_state(sd);
70 
71 	state->input = input;
72 	state->output = output;
73 	m52790_write(sd);
74 	return 0;
75 }
76 
77 #ifdef CONFIG_VIDEO_ADV_DEBUG
78 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
79 {
80 	struct m52790_state *state = to_state(sd);
81 
82 	if (reg->reg != 0)
83 		return -EINVAL;
84 	reg->size = 1;
85 	reg->val = state->input | state->output;
86 	return 0;
87 }
88 
89 static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
90 {
91 	struct m52790_state *state = to_state(sd);
92 
93 	if (reg->reg != 0)
94 		return -EINVAL;
95 	state->input = reg->val & 0x0303;
96 	state->output = reg->val & ~0x0303;
97 	m52790_write(sd);
98 	return 0;
99 }
100 #endif
101 
102 static int m52790_log_status(struct v4l2_subdev *sd)
103 {
104 	struct m52790_state *state = to_state(sd);
105 
106 	v4l2_info(sd, "Switch 1: %02x\n",
107 			(state->input | state->output) & 0xff);
108 	v4l2_info(sd, "Switch 2: %02x\n",
109 			(state->input | state->output) >> 8);
110 	return 0;
111 }
112 
113 /* ----------------------------------------------------------------------- */
114 
115 static const struct v4l2_subdev_core_ops m52790_core_ops = {
116 	.log_status = m52790_log_status,
117 #ifdef CONFIG_VIDEO_ADV_DEBUG
118 	.g_register = m52790_g_register,
119 	.s_register = m52790_s_register,
120 #endif
121 };
122 
123 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
124 	.s_routing = m52790_s_routing,
125 };
126 
127 static const struct v4l2_subdev_video_ops m52790_video_ops = {
128 	.s_routing = m52790_s_routing,
129 };
130 
131 static const struct v4l2_subdev_ops m52790_ops = {
132 	.core = &m52790_core_ops,
133 	.audio = &m52790_audio_ops,
134 	.video = &m52790_video_ops,
135 };
136 
137 /* ----------------------------------------------------------------------- */
138 
139 /* i2c implementation */
140 
141 static int m52790_probe(struct i2c_client *client,
142 			const struct i2c_device_id *id)
143 {
144 	struct m52790_state *state;
145 	struct v4l2_subdev *sd;
146 
147 	/* Check if the adapter supports the needed features */
148 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
149 		return -EIO;
150 
151 	v4l_info(client, "chip found @ 0x%x (%s)\n",
152 			client->addr << 1, client->adapter->name);
153 
154 	state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
155 	if (state == NULL)
156 		return -ENOMEM;
157 
158 	sd = &state->sd;
159 	v4l2_i2c_subdev_init(sd, client, &m52790_ops);
160 	state->input = M52790_IN_TUNER;
161 	state->output = M52790_OUT_STEREO;
162 	m52790_write(sd);
163 	return 0;
164 }
165 
166 static int m52790_remove(struct i2c_client *client)
167 {
168 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
169 
170 	v4l2_device_unregister_subdev(sd);
171 	return 0;
172 }
173 
174 /* ----------------------------------------------------------------------- */
175 
176 static const struct i2c_device_id m52790_id[] = {
177 	{ "m52790", 0 },
178 	{ }
179 };
180 MODULE_DEVICE_TABLE(i2c, m52790_id);
181 
182 static struct i2c_driver m52790_driver = {
183 	.driver = {
184 		.name	= "m52790",
185 	},
186 	.probe		= m52790_probe,
187 	.remove		= m52790_remove,
188 	.id_table	= m52790_id,
189 };
190 
191 module_i2c_driver(m52790_driver);
192