media/i2c/m52790.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * m52790 i2c ivtv driver.
0004  * Copyright (C) 2007  Hans Verkuil
0005  *
0006  * A/V source switching Mitsubishi M52790SP/FP
0007  */
0008
0009
0010 #include <linux/module.h>
0011 #include <linux/types.h>
0012 #include <linux/slab.h>
0013 #include <linux/ioctl.h>
0014 #include <linux/uaccess.h>
0015 #include <linux/i2c.h>
0016 #include <linux/videodev2.h>
0017 #include <media/i2c/m52790.h>
0018 #include <media/v4l2-device.h>
0019
0020 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
0021 MODULE_AUTHOR("Hans Verkuil");
0022 MODULE_LICENSE("GPL");
0023
0024
0025 struct m52790_state {
0026     struct v4l2_subdev sd;
0027     u16 input;
0028     u16 output;
0029 };
0030
0031 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
0032 {
0033     return container_of(sd, struct m52790_state, sd);
0034 }
0035
0036 /* ----------------------------------------------------------------------- */
0037
0038 static int m52790_write(struct v4l2_subdev *sd)
0039 {
0040     struct m52790_state *state = to_state(sd);
0041     struct i2c_client *client = v4l2_get_subdevdata(sd);
0042
0043     u8 sw1 = (state->input | state->output) & 0xff;
0044     u8 sw2 = (state->input | state->output) >> 8;
0045
0046     return i2c_smbus_write_byte_data(client, sw1, sw2);
0047 }
0048
0049 /* Note: audio and video are linked and cannot be switched separately.
0050    So audio and video routing commands are identical for this chip.
0051    In theory the video amplifier and audio modes could be handled
0052    separately for the output, but that seems to be overkill right now.
0053    The same holds for implementing an audio mute control, this is now
0054    part of the audio output routing. The normal case is that another
0055    chip takes care of the actual muting so making it part of the
0056    output routing seems to be the right thing to do for now. */
0057 static int m52790_s_routing(struct v4l2_subdev *sd,
0058                 u32 input, u32 output, u32 config)
0059 {
0060     struct m52790_state *state = to_state(sd);
0061
0062     state->input = input;
0063     state->output = output;
0064     m52790_write(sd);
0065     return 0;
0066 }
0067
0068 #ifdef CONFIG_VIDEO_ADV_DEBUG
0069 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
0070 {
0071     struct m52790_state *state = to_state(sd);
0072
0073     if (reg->reg != 0)
0074         return -EINVAL;
0075     reg->size = 1;
0076     reg->val = state->input | state->output;
0077     return 0;
0078 }
0079
0080 static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
0081 {
0082     struct m52790_state *state = to_state(sd);
0083
0084     if (reg->reg != 0)
0085         return -EINVAL;
0086     state->input = reg->val & 0x0303;
0087     state->output = reg->val & ~0x0303;
0088     m52790_write(sd);
0089     return 0;
0090 }
0091 #endif
0092
0093 static int m52790_log_status(struct v4l2_subdev *sd)
0094 {
0095     struct m52790_state *state = to_state(sd);
0096
0097     v4l2_info(sd, "Switch 1: %02x\n",
0098             (state->input | state->output) & 0xff);
0099     v4l2_info(sd, "Switch 2: %02x\n",
0100             (state->input | state->output) >> 8);
0101     return 0;
0102 }
0103
0104 /* ----------------------------------------------------------------------- */
0105
0106 static const struct v4l2_subdev_core_ops m52790_core_ops = {
0107     .log_status = m52790_log_status,
0108 #ifdef CONFIG_VIDEO_ADV_DEBUG
0109     .g_register = m52790_g_register,
0110     .s_register = m52790_s_register,
0111 #endif
0112 };
0113
0114 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
0115     .s_routing = m52790_s_routing,
0116 };
0117
0118 static const struct v4l2_subdev_video_ops m52790_video_ops = {
0119     .s_routing = m52790_s_routing,
0120 };
0121
0122 static const struct v4l2_subdev_ops m52790_ops = {
0123     .core = &m52790_core_ops,
0124     .audio = &m52790_audio_ops,
0125     .video = &m52790_video_ops,
0126 };
0127
0128 /* ----------------------------------------------------------------------- */
0129
0130 /* i2c implementation */
0131
0132 static int m52790_probe(struct i2c_client *client,
0133             const struct i2c_device_id *id)
0134 {
0135     struct m52790_state *state;
0136     struct v4l2_subdev *sd;
0137
0138     /* Check if the adapter supports the needed features */
0139     if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
0140         return -EIO;
0141
0142     v4l_info(client, "chip found @ 0x%x (%s)\n",
0143             client->addr << 1, client->adapter->name);
0144
0145     state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
0146     if (state == NULL)
0147         return -ENOMEM;
0148
0149     sd = &state->sd;
0150     v4l2_i2c_subdev_init(sd, client, &m52790_ops);
0151     state->input = M52790_IN_TUNER;
0152     state->output = M52790_OUT_STEREO;
0153     m52790_write(sd);
0154     return 0;
0155 }
0156
0157 static int m52790_remove(struct i2c_client *client)
0158 {
0159     struct v4l2_subdev *sd = i2c_get_clientdata(client);
0160
0161     v4l2_device_unregister_subdev(sd);
0162     return 0;
0163 }
0164
0165 /* ----------------------------------------------------------------------- */
0166
0167 static const struct i2c_device_id m52790_id[] = {
0168     { "m52790", 0 },
0169     { }
0170 };
0171 MODULE_DEVICE_TABLE(i2c, m52790_id);
0172
0173 static struct i2c_driver m52790_driver = {
0174     .driver = {
0175         .name   = "m52790",
0176     },
0177     .probe      = m52790_probe,
0178     .remove     = m52790_remove,
0179     .id_table   = m52790_id,
0180 };
0181
0182 module_i2c_driver(m52790_driver);