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/videodev2.h>
  30 #include <media/m52790.h>
  31 #include <media/v4l2-device.h>
  32 #include <media/v4l2-chip-ident.h>
  33
  34 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
  35 MODULE_AUTHOR("Hans Verkuil");
  36 MODULE_LICENSE("GPL");
  37
  38
  39 struct m52790_state {
  40         struct v4l2_subdev sd;
  41         u16 input;
  42         u16 output;
  43 };
  44
  45 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
  46 {
  47         return container_of(sd, struct m52790_state, sd);
  48 }
  49
  50 /* ----------------------------------------------------------------------- */
  51
  52 static int m52790_write(struct v4l2_subdev *sd)
  53 {
  54         struct m52790_state *state = to_state(sd);
  55         struct i2c_client *client = v4l2_get_subdevdata(sd);
  56
  57         u8 sw1 = (state->input | state->output) & 0xff;
  58         u8 sw2 = (state->input | state->output) >> 8;
  59
  60         return i2c_smbus_write_byte_data(client, sw1, sw2);
  61 }
  62
  63 /* Note: audio and video are linked and cannot be switched separately.
  64    So audio and video routing commands are identical for this chip.
  65    In theory the video amplifier and audio modes could be handled
  66    separately for the output, but that seems to be overkill right now.
  67    The same holds for implementing an audio mute control, this is now
  68    part of the audio output routing. The normal case is that another
  69    chip takes care of the actual muting so making it part of the
  70    output routing seems to be the right thing to do for now. */
  71 static int m52790_s_routing(struct v4l2_subdev *sd,
  72                             u32 input, u32 output, u32 config)
  73 {
  74         struct m52790_state *state = to_state(sd);
  75
  76         state->input = input;
  77         state->output = output;
  78         m52790_write(sd);
  79         return 0;
  80 }
  81
  82 #ifdef CONFIG_VIDEO_ADV_DEBUG
  83 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
  84 {
  85         struct m52790_state *state = to_state(sd);
  86         struct i2c_client *client = v4l2_get_subdevdata(sd);
  87
  88         if (!v4l2_chip_match_i2c_client(client, &reg->match))
  89                 return -EINVAL;
  90         if (!capable(CAP_SYS_ADMIN))
  91                 return -EPERM;
  92         if (reg->reg != 0)
  93                 return -EINVAL;
  94         reg->size = 1;
  95         reg->val = state->input | state->output;
  96         return 0;
  97 }
  98
  99 static int m52790_s_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
 100 {
 101         struct m52790_state *state = to_state(sd);
 102         struct i2c_client *client = v4l2_get_subdevdata(sd);
 103
 104         if (!v4l2_chip_match_i2c_client(client, &reg->match))
 105                 return -EINVAL;
 106         if (!capable(CAP_SYS_ADMIN))
 107                 return -EPERM;
 108         if (reg->reg != 0)
 109                 return -EINVAL;
 110         state->input = reg->val & 0x0303;
 111         state->output = reg->val & ~0x0303;
 112         m52790_write(sd);
 113         return 0;
 114 }
 115 #endif
 116
 117 static int m52790_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
 118 {
 119         struct i2c_client *client = v4l2_get_subdevdata(sd);
 120
 121         return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_M52790, 0);
 122 }
 123
 124 static int m52790_log_status(struct v4l2_subdev *sd)
 125 {
 126         struct m52790_state *state = to_state(sd);
 127
 128         v4l2_info(sd, "Switch 1: %02x\n",
 129                         (state->input | state->output) & 0xff);
 130         v4l2_info(sd, "Switch 2: %02x\n",
 131                         (state->input | state->output) >> 8);
 132         return 0;
 133 }
 134
 135 /* ----------------------------------------------------------------------- */
 136
 137 static const struct v4l2_subdev_core_ops m52790_core_ops = {
 138         .log_status = m52790_log_status,
 139         .g_chip_ident = m52790_g_chip_ident,
 140 #ifdef CONFIG_VIDEO_ADV_DEBUG
 141         .g_register = m52790_g_register,
 142         .s_register = m52790_s_register,
 143 #endif
 144 };
 145
 146 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
 147         .s_routing = m52790_s_routing,
 148 };
 149
 150 static const struct v4l2_subdev_video_ops m52790_video_ops = {
 151         .s_routing = m52790_s_routing,
 152 };
 153
 154 static const struct v4l2_subdev_ops m52790_ops = {
 155         .core = &m52790_core_ops,
 156         .audio = &m52790_audio_ops,
 157         .video = &m52790_video_ops,
 158 };
 159
 160 /* ----------------------------------------------------------------------- */
 161
 162 /* i2c implementation */
 163
 164 static int m52790_probe(struct i2c_client *client,
 165                         const struct i2c_device_id *id)
 166 {
 167         struct m52790_state *state;
 168         struct v4l2_subdev *sd;
 169
 170         /* Check if the adapter supports the needed features */
 171         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 172                 return -EIO;
 173
 174         v4l_info(client, "chip found @ 0x%x (%s)\n",
 175                         client->addr << 1, client->adapter->name);
 176
 177         state = kmalloc(sizeof(struct m52790_state), GFP_KERNEL);
 178         if (state == NULL)
 179                 return -ENOMEM;
 180
 181         sd = &state->sd;
 182         v4l2_i2c_subdev_init(sd, client, &m52790_ops);
 183         state->input = M52790_IN_TUNER;
 184         state->output = M52790_OUT_STEREO;
 185         m52790_write(sd);
 186         return 0;
 187 }
 188
 189 static int m52790_remove(struct i2c_client *client)
 190 {
 191         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 192
 193         v4l2_device_unregister_subdev(sd);
 194         kfree(to_state(sd));
 195         return 0;
 196 }
 197
 198 /* ----------------------------------------------------------------------- */
 199
 200 static const struct i2c_device_id m52790_id[] = {
 201         { "m52790", 0 },
 202         { }
 203 };
 204 MODULE_DEVICE_TABLE(i2c, m52790_id);
 205
 206 static struct i2c_driver m52790_driver = {
 207         .driver = {
 208                 .owner  = THIS_MODULE,
 209                 .name   = "m52790",
 210         },
 211         .probe          = m52790_probe,
 212         .remove         = m52790_remove,
 213         .id_table       = m52790_id,
 214 };
 215
 216 static __init int init_m52790(void)
 217 {
 218         return i2c_add_driver(&m52790_driver);
 219 }
 220
 221 static __exit void exit_m52790(void)
 222 {
 223         i2c_del_driver(&m52790_driver);
 224 }
 225
 226 module_init(init_m52790);
 227 module_exit(exit_m52790);