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