drivers/media/i2c/m52790.c

   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);