xref: /linux/drivers/media/i2c/m52790.c (revision 257ca10c7317d4a424e48bb95d14ca53a1f1dd6f)
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 
20 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
21 MODULE_AUTHOR("Hans Verkuil");
22 MODULE_LICENSE("GPL");
23 
24 
25 struct m52790_state {
26 	struct v4l2_subdev sd;
27 	u16 input;
28 	u16 output;
29 };
30 
31 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
32 {
33 	return container_of(sd, struct m52790_state, sd);
34 }
35 
36 /* ----------------------------------------------------------------------- */
37 
38 static 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. */
57 static 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
69 static 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 
80 static 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 
93 static 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 
106 static 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 
114 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
115 	.s_routing = m52790_s_routing,
116 };
117 
118 static const struct v4l2_subdev_video_ops m52790_video_ops = {
119 	.s_routing = m52790_s_routing,
120 };
121 
122 static 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 
132 static 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 
156 static 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 
165 static const struct i2c_device_id m52790_id[] = {
166 	{ "m52790", 0 },
167 	{ }
168 };
169 MODULE_DEVICE_TABLE(i2c, m52790_id);
170 
171 static 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 
180 module_i2c_driver(m52790_driver);
181