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  * 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 <linux/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);