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/ioctl.h>
  26 #include <asm/uaccess.h>
  27 #include <linux/i2c.h>
  28 #include <linux/i2c-id.h>
  29 #include <linux/videodev.h>
  30 #include <media/m52790.h>
  31 #include <media/v4l2-common.h>
  32 #include <media/v4l2-chip-ident.h>
  33 #include <media/v4l2-i2c-drv-legacy.h>
  34
  35 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
  36 MODULE_AUTHOR("Hans Verkuil");
  37 MODULE_LICENSE("GPL");
  38
  39 static unsigned short normal_i2c[] = { 0x90 >> 1, I2C_CLIENT_END };
  40
  41
  42 I2C_CLIENT_INSMOD;
  43
  44 struct m52790_state {
  45         u16 input;
  46         u16 output;
  47 };
  48
  49 /* ----------------------------------------------------------------------- */
  50
  51 static int m52790_write(struct i2c_client *client)
  52 {
  53         struct m52790_state *state = i2c_get_clientdata(client);
  54         u8 sw1 = (state->input | state->output) & 0xff;
  55         u8 sw2 = (state->input | state->output) >> 8;
  56
  57         return i2c_smbus_write_byte_data(client, sw1, sw2);
  58 }
  59
  60 static int m52790_command(struct i2c_client *client, unsigned int cmd,
  61                             void *arg)
  62 {
  63         struct m52790_state *state = i2c_get_clientdata(client);
  64         struct v4l2_routing *route = arg;
  65
  66         /* Note: audio and video are linked and cannot be switched separately.
  67            So audio and video routing commands are identical for this chip.
  68            In theory the video amplifier and audio modes could be handled
  69            separately for the output, but that seems to be overkill right now.
  70            The same holds for implementing an audio mute control, this is now
  71            part of the audio output routing. The normal case is that another
  72            chip takes care of the actual muting so making it part of the
  73            output routing seems to be the right thing to do for now. */
  74         switch (cmd) {
  75         case VIDIOC_INT_G_AUDIO_ROUTING:
  76         case VIDIOC_INT_G_VIDEO_ROUTING:
  77                 route->input = state->input;
  78                 route->output = state->output;
  79                 break;
  80
  81         case VIDIOC_INT_S_AUDIO_ROUTING:
  82         case VIDIOC_INT_S_VIDEO_ROUTING:
  83                 state->input = route->input;
  84                 state->output = route->output;
  85                 m52790_write(client);
  86                 break;
  87
  88 #ifdef CONFIG_VIDEO_ADV_DEBUG
  89         case VIDIOC_DBG_G_REGISTER:
  90         case VIDIOC_DBG_S_REGISTER:
  91         {
  92                 struct v4l2_register *reg = arg;
  93
  94                 if (!v4l2_chip_match_i2c_client(client,
  95                                         reg->match_type, reg->match_chip))
  96                         return -EINVAL;
  97                 if (!capable(CAP_SYS_ADMIN))
  98                         return -EPERM;
  99                 if (reg->reg != 0)
 100                         return -EINVAL;
 101                 if (cmd == VIDIOC_DBG_G_REGISTER)
 102                         reg->val = state->input | state->output;
 103                 else {
 104                         state->input = reg->val & 0x0303;
 105                         state->output = reg->val & ~0x0303;
 106                         m52790_write(client);
 107                 }
 108                 break;
 109         }
 110 #endif
 111
 112         case VIDIOC_G_CHIP_IDENT:
 113                 return v4l2_chip_ident_i2c_client(client, arg,
 114                                 V4L2_IDENT_M52790, 0);
 115
 116         case VIDIOC_LOG_STATUS:
 117                 v4l_info(client, "Switch 1: %02x\n",
 118                                 (state->input | state->output) & 0xff);
 119                 v4l_info(client, "Switch 2: %02x\n",
 120                                 (state->input | state->output) >> 8);
 121                 break;
 122
 123         default:
 124                 return -EINVAL;
 125         }
 126         return 0;
 127 }
 128
 129 /* ----------------------------------------------------------------------- */
 130
 131 /* i2c implementation */
 132
 133 static int m52790_probe(struct i2c_client *client)
 134 {
 135         struct m52790_state *state;
 136
 137         /* Check if the adapter supports the needed features */
 138         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 139                 return -EIO;
 140
 141         snprintf(client->name, sizeof(client->name) - 1, "m52790");
 142
 143         v4l_info(client, "chip found @ 0x%x (%s)\n",
 144                         client->addr << 1, client->adapter->name);
 145
 146         state = kmalloc(sizeof(struct m52790_state), GFP_KERNEL);
 147         if (state == NULL)
 148                 return -ENOMEM;
 149
 150         state->input = M52790_IN_TUNER;
 151         state->output = M52790_OUT_STEREO;
 152         i2c_set_clientdata(client, state);
 153         m52790_write(client);
 154         return 0;
 155 }
 156
 157 static int m52790_remove(struct i2c_client *client)
 158 {
 159         kfree(i2c_get_clientdata(client));
 160         return 0;
 161 }
 162
 163 /* ----------------------------------------------------------------------- */
 164
 165 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
 166         .name = "m52790",
 167         .driverid = I2C_DRIVERID_M52790,
 168         .command = m52790_command,
 169         .probe = m52790_probe,
 170         .remove = m52790_remove,
 171 };
 172