release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/media/video/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 <asm/uaccess.h>
  28 #include <linux/i2c.h>
  29 #include <linux/i2c-id.h>
  30 #include <linux/videodev2.h>
  31 #include <media/m52790.h>
  32 #include <media/v4l2-device.h>
  33 #include <media/v4l2-chip-ident.h>
  34 #include <media/v4l2-i2c-drv.h>
  35
  36 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
  37 MODULE_AUTHOR("Hans Verkuil");
  38 MODULE_LICENSE("GPL");
  39
  40
  41 struct m52790_state {
  42         struct v4l2_subdev sd;
  43         u16 input;
  44         u16 output;
  45 };
  46
  47 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
  48 {
  49         return container_of(sd, struct m52790_state, sd);
  50 }
  51
  52 /* ----------------------------------------------------------------------- */
  53
  54 static int m52790_write(struct v4l2_subdev *sd)
  55 {
  56         struct m52790_state *state = to_state(sd);
  57         struct i2c_client *client = v4l2_get_subdevdata(sd);
  58
  59         u8 sw1 = (state->input | state->output) & 0xff;
  60         u8 sw2 = (state->input | state->output) >> 8;
  61
  62         return i2c_smbus_write_byte_data(client, sw1, sw2);
  63 }
  64
  65 /* Note: audio and video are linked and cannot be switched separately.
  66    So audio and video routing commands are identical for this chip.
  67    In theory the video amplifier and audio modes could be handled
  68    separately for the output, but that seems to be overkill right now.
  69    The same holds for implementing an audio mute control, this is now
  70    part of the audio output routing. The normal case is that another
  71    chip takes care of the actual muting so making it part of the
  72    output routing seems to be the right thing to do for now. */
  73 static int m52790_s_routing(struct v4l2_subdev *sd,
  74                             u32 input, u32 output, u32 config)
  75 {
  76         struct m52790_state *state = to_state(sd);
  77
  78         state->input = input;
  79         state->output = output;
  80         m52790_write(sd);
  81         return 0;
  82 }
  83
  84 #ifdef CONFIG_VIDEO_ADV_DEBUG
  85 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
  86 {
  87         struct m52790_state *state = to_state(sd);
  88         struct i2c_client *client = v4l2_get_subdevdata(sd);
  89
  90         if (!v4l2_chip_match_i2c_client(client, &reg->match))
  91                 return -EINVAL;
  92         if (!capable(CAP_SYS_ADMIN))
  93                 return -EPERM;
  94         if (reg->reg != 0)
  95                 return -EINVAL;
  96         reg->size = 1;
  97         reg->val = state->input | state->output;
  98         return 0;
  99 }
 100
 101 static int m52790_s_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
 102 {
 103         struct m52790_state *state = to_state(sd);
 104         struct i2c_client *client = v4l2_get_subdevdata(sd);
 105
 106         if (!v4l2_chip_match_i2c_client(client, &reg->match))
 107                 return -EINVAL;
 108         if (!capable(CAP_SYS_ADMIN))
 109                 return -EPERM;
 110         if (reg->reg != 0)
 111                 return -EINVAL;
 112         state->input = reg->val & 0x0303;
 113         state->output = reg->val & ~0x0303;
 114         m52790_write(sd);
 115         return 0;
 116 }
 117 #endif
 118
 119 static int m52790_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
 120 {
 121         struct i2c_client *client = v4l2_get_subdevdata(sd);
 122
 123         return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_M52790, 0);
 124 }
 125
 126 static int m52790_log_status(struct v4l2_subdev *sd)
 127 {
 128         struct m52790_state *state = to_state(sd);
 129
 130         v4l2_info(sd, "Switch 1: %02x\n",
 131                         (state->input | state->output) & 0xff);
 132         v4l2_info(sd, "Switch 2: %02x\n",
 133                         (state->input | state->output) >> 8);
 134         return 0;
 135 }
 136
 137 /* ----------------------------------------------------------------------- */
 138
 139 static const struct v4l2_subdev_core_ops m52790_core_ops = {
 140         .log_status = m52790_log_status,
 141         .g_chip_ident = m52790_g_chip_ident,
 142 #ifdef CONFIG_VIDEO_ADV_DEBUG
 143         .g_register = m52790_g_register,
 144         .s_register = m52790_s_register,
 145 #endif
 146 };
 147
 148 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
 149         .s_routing = m52790_s_routing,
 150 };
 151
 152 static const struct v4l2_subdev_video_ops m52790_video_ops = {
 153         .s_routing = m52790_s_routing,
 154 };
 155
 156 static const struct v4l2_subdev_ops m52790_ops = {
 157         .core = &m52790_core_ops,
 158         .audio = &m52790_audio_ops,
 159         .video = &m52790_video_ops,
 160 };
 161
 162 /* ----------------------------------------------------------------------- */
 163
 164 /* i2c implementation */
 165
 166 static int m52790_probe(struct i2c_client *client,
 167                         const struct i2c_device_id *id)
 168 {
 169         struct m52790_state *state;
 170         struct v4l2_subdev *sd;
 171
 172         /* Check if the adapter supports the needed features */
 173         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 174                 return -EIO;
 175
 176         v4l_info(client, "chip found @ 0x%x (%s)\n",
 177                         client->addr << 1, client->adapter->name);
 178
 179         state = kmalloc(sizeof(struct m52790_state), GFP_KERNEL);
 180         if (state == NULL)
 181                 return -ENOMEM;
 182
 183         sd = &state->sd;
 184         v4l2_i2c_subdev_init(sd, client, &m52790_ops);
 185         state->input = M52790_IN_TUNER;
 186         state->output = M52790_OUT_STEREO;
 187         m52790_write(sd);
 188         return 0;
 189 }
 190
 191 static int m52790_remove(struct i2c_client *client)
 192 {
 193         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 194
 195         v4l2_device_unregister_subdev(sd);
 196         kfree(to_state(sd));
 197         return 0;
 198 }
 199
 200 /* ----------------------------------------------------------------------- */
 201
 202 static const struct i2c_device_id m52790_id[] = {
 203         { "m52790", 0 },
 204         { }
 205 };
 206 MODULE_DEVICE_TABLE(i2c, m52790_id);
 207
 208 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
 209         .name = "m52790",
 210         .probe = m52790_probe,
 211         .remove = m52790_remove,
 212         .id_table = m52790_id,
 213 };