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/m52790.h>
31#include <media/v4l2-device.h>
32
33MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
34MODULE_AUTHOR("Hans Verkuil");
35MODULE_LICENSE("GPL");
36
37
38struct m52790_state {
39	struct v4l2_subdev sd;
40	u16 input;
41	u16 output;
42};
43
44static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
45{
46	return container_of(sd, struct m52790_state, sd);
47}
48
49/* ----------------------------------------------------------------------- */
50
51static 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. */
70static 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
82static 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
93static 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
106static 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
119static 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
127static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
128	.s_routing = m52790_s_routing,
129};
130
131static const struct v4l2_subdev_video_ops m52790_video_ops = {
132	.s_routing = m52790_s_routing,
133};
134
135static 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
145static 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
170static 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
180static const struct i2c_device_id m52790_id[] = {
181	{ "m52790", 0 },
182	{ }
183};
184MODULE_DEVICE_TABLE(i2c, m52790_id);
185
186static struct i2c_driver m52790_driver = {
187	.driver = {
188		.owner	= THIS_MODULE,
189		.name	= "m52790",
190	},
191	.probe		= m52790_probe,
192	.remove		= m52790_remove,
193	.id_table	= m52790_id,
194};
195
196module_i2c_driver(m52790_driver);
197