xref: /openbmc/linux/drivers/media/i2c/m52790.c (revision 8c749ce9)
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  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 
23 #include <linux/module.h>
24 #include <linux/types.h>
25 #include <linux/slab.h>
26 #include <linux/ioctl.h>
27 #include <asm/uaccess.h>
28 #include <linux/i2c.h>
29 #include <linux/videodev2.h>
30 #include <media/i2c/m52790.h>
31 #include <media/v4l2-device.h>
32 
33 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
34 MODULE_AUTHOR("Hans Verkuil");
35 MODULE_LICENSE("GPL");
36 
37 
38 struct m52790_state {
39 	struct v4l2_subdev sd;
40 	u16 input;
41 	u16 output;
42 };
43 
44 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
45 {
46 	return container_of(sd, struct m52790_state, sd);
47 }
48 
49 /* ----------------------------------------------------------------------- */
50 
51 static int m52790_write(struct v4l2_subdev *sd)
52 {
53 	struct m52790_state *state = to_state(sd);
54 	struct i2c_client *client = v4l2_get_subdevdata(sd);
55 
56 	u8 sw1 = (state->input | state->output) & 0xff;
57 	u8 sw2 = (state->input | state->output) >> 8;
58 
59 	return i2c_smbus_write_byte_data(client, sw1, sw2);
60 }
61 
62 /* Note: audio and video are linked and cannot be switched separately.
63    So audio and video routing commands are identical for this chip.
64    In theory the video amplifier and audio modes could be handled
65    separately for the output, but that seems to be overkill right now.
66    The same holds for implementing an audio mute control, this is now
67    part of the audio output routing. The normal case is that another
68    chip takes care of the actual muting so making it part of the
69    output routing seems to be the right thing to do for now. */
70 static int m52790_s_routing(struct v4l2_subdev *sd,
71 			    u32 input, u32 output, u32 config)
72 {
73 	struct m52790_state *state = to_state(sd);
74 
75 	state->input = input;
76 	state->output = output;
77 	m52790_write(sd);
78 	return 0;
79 }
80 
81 #ifdef CONFIG_VIDEO_ADV_DEBUG
82 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
83 {
84 	struct m52790_state *state = to_state(sd);
85 
86 	if (reg->reg != 0)
87 		return -EINVAL;
88 	reg->size = 1;
89 	reg->val = state->input | state->output;
90 	return 0;
91 }
92 
93 static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
94 {
95 	struct m52790_state *state = to_state(sd);
96 
97 	if (reg->reg != 0)
98 		return -EINVAL;
99 	state->input = reg->val & 0x0303;
100 	state->output = reg->val & ~0x0303;
101 	m52790_write(sd);
102 	return 0;
103 }
104 #endif
105 
106 static int m52790_log_status(struct v4l2_subdev *sd)
107 {
108 	struct m52790_state *state = to_state(sd);
109 
110 	v4l2_info(sd, "Switch 1: %02x\n",
111 			(state->input | state->output) & 0xff);
112 	v4l2_info(sd, "Switch 2: %02x\n",
113 			(state->input | state->output) >> 8);
114 	return 0;
115 }
116 
117 /* ----------------------------------------------------------------------- */
118 
119 static const struct v4l2_subdev_core_ops m52790_core_ops = {
120 	.log_status = m52790_log_status,
121 #ifdef CONFIG_VIDEO_ADV_DEBUG
122 	.g_register = m52790_g_register,
123 	.s_register = m52790_s_register,
124 #endif
125 };
126 
127 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
128 	.s_routing = m52790_s_routing,
129 };
130 
131 static const struct v4l2_subdev_video_ops m52790_video_ops = {
132 	.s_routing = m52790_s_routing,
133 };
134 
135 static const struct v4l2_subdev_ops m52790_ops = {
136 	.core = &m52790_core_ops,
137 	.audio = &m52790_audio_ops,
138 	.video = &m52790_video_ops,
139 };
140 
141 /* ----------------------------------------------------------------------- */
142 
143 /* i2c implementation */
144 
145 static int m52790_probe(struct i2c_client *client,
146 			const struct i2c_device_id *id)
147 {
148 	struct m52790_state *state;
149 	struct v4l2_subdev *sd;
150 
151 	/* Check if the adapter supports the needed features */
152 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
153 		return -EIO;
154 
155 	v4l_info(client, "chip found @ 0x%x (%s)\n",
156 			client->addr << 1, client->adapter->name);
157 
158 	state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
159 	if (state == NULL)
160 		return -ENOMEM;
161 
162 	sd = &state->sd;
163 	v4l2_i2c_subdev_init(sd, client, &m52790_ops);
164 	state->input = M52790_IN_TUNER;
165 	state->output = M52790_OUT_STEREO;
166 	m52790_write(sd);
167 	return 0;
168 }
169 
170 static int m52790_remove(struct i2c_client *client)
171 {
172 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
173 
174 	v4l2_device_unregister_subdev(sd);
175 	return 0;
176 }
177 
178 /* ----------------------------------------------------------------------- */
179 
180 static const struct i2c_device_id m52790_id[] = {
181 	{ "m52790", 0 },
182 	{ }
183 };
184 MODULE_DEVICE_TABLE(i2c, m52790_id);
185 
186 static struct i2c_driver m52790_driver = {
187 	.driver = {
188 		.name	= "m52790",
189 	},
190 	.probe		= m52790_probe,
191 	.remove		= m52790_remove,
192 	.id_table	= m52790_id,
193 };
194 
195 module_i2c_driver(m52790_driver);
196