root/drivers/media/i2c/m52790.c

DEFINITIONS

1. to_state
2. m52790_write
3. m52790_s_routing
4. m52790_g_register
5. m52790_s_register
6. m52790_log_status
7. m52790_probe
8. m52790_remove

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * m52790 i2c ivtv driver.
   4  * Copyright (C) 2007  Hans Verkuil
   5  *
   6  * A/V source switching Mitsubishi M52790SP/FP
   7  */
   8 
   9 
  10 #include <linux/module.h>
  11 #include <linux/types.h>
  12 #include <linux/slab.h>
  13 #include <linux/ioctl.h>
  14 #include <linux/uaccess.h>
  15 #include <linux/i2c.h>
  16 #include <linux/videodev2.h>
  17 #include <media/i2c/m52790.h>
  18 #include <media/v4l2-device.h>
  19 
  20 MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
  21 MODULE_AUTHOR("Hans Verkuil");
  22 MODULE_LICENSE("GPL");
  23 
  24 
  25 struct m52790_state {
  26         struct v4l2_subdev sd;
  27         u16 input;
  28         u16 output;
  29 };
  30 
  31 static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
  32 {
  33         return container_of(sd, struct m52790_state, sd);
  34 }
  35 
  36 /* ----------------------------------------------------------------------- */
  37 
  38 static int m52790_write(struct v4l2_subdev *sd)
  39 {
  40         struct m52790_state *state = to_state(sd);
  41         struct i2c_client *client = v4l2_get_subdevdata(sd);
  42 
  43         u8 sw1 = (state->input | state->output) & 0xff;
  44         u8 sw2 = (state->input | state->output) >> 8;
  45 
  46         return i2c_smbus_write_byte_data(client, sw1, sw2);
  47 }
  48 
  49 /* Note: audio and video are linked and cannot be switched separately.
  50    So audio and video routing commands are identical for this chip.
  51    In theory the video amplifier and audio modes could be handled
  52    separately for the output, but that seems to be overkill right now.
  53    The same holds for implementing an audio mute control, this is now
  54    part of the audio output routing. The normal case is that another
  55    chip takes care of the actual muting so making it part of the
  56    output routing seems to be the right thing to do for now. */
  57 static int m52790_s_routing(struct v4l2_subdev *sd,
  58                             u32 input, u32 output, u32 config)
  59 {
  60         struct m52790_state *state = to_state(sd);
  61 
  62         state->input = input;
  63         state->output = output;
  64         m52790_write(sd);
  65         return 0;
  66 }
  67 
  68 #ifdef CONFIG_VIDEO_ADV_DEBUG
  69 static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
  70 {
  71         struct m52790_state *state = to_state(sd);
  72 
  73         if (reg->reg != 0)
  74                 return -EINVAL;
  75         reg->size = 1;
  76         reg->val = state->input | state->output;
  77         return 0;
  78 }
  79 
  80 static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
  81 {
  82         struct m52790_state *state = to_state(sd);
  83 
  84         if (reg->reg != 0)
  85                 return -EINVAL;
  86         state->input = reg->val & 0x0303;
  87         state->output = reg->val & ~0x0303;
  88         m52790_write(sd);
  89         return 0;
  90 }
  91 #endif
  92 
  93 static int m52790_log_status(struct v4l2_subdev *sd)
  94 {
  95         struct m52790_state *state = to_state(sd);
  96 
  97         v4l2_info(sd, "Switch 1: %02x\n",
  98                         (state->input | state->output) & 0xff);
  99         v4l2_info(sd, "Switch 2: %02x\n",
 100                         (state->input | state->output) >> 8);
 101         return 0;
 102 }
 103 
 104 /* ----------------------------------------------------------------------- */
 105 
 106 static const struct v4l2_subdev_core_ops m52790_core_ops = {
 107         .log_status = m52790_log_status,
 108 #ifdef CONFIG_VIDEO_ADV_DEBUG
 109         .g_register = m52790_g_register,
 110         .s_register = m52790_s_register,
 111 #endif
 112 };
 113 
 114 static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
 115         .s_routing = m52790_s_routing,
 116 };
 117 
 118 static const struct v4l2_subdev_video_ops m52790_video_ops = {
 119         .s_routing = m52790_s_routing,
 120 };
 121 
 122 static const struct v4l2_subdev_ops m52790_ops = {
 123         .core = &m52790_core_ops,
 124         .audio = &m52790_audio_ops,
 125         .video = &m52790_video_ops,
 126 };
 127 
 128 /* ----------------------------------------------------------------------- */
 129 
 130 /* i2c implementation */
 131 
 132 static int m52790_probe(struct i2c_client *client,
 133                         const struct i2c_device_id *id)
 134 {
 135         struct m52790_state *state;
 136         struct v4l2_subdev *sd;
 137 
 138         /* Check if the adapter supports the needed features */
 139         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 140                 return -EIO;
 141 
 142         v4l_info(client, "chip found @ 0x%x (%s)\n",
 143                         client->addr << 1, client->adapter->name);
 144 
 145         state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
 146         if (state == NULL)
 147                 return -ENOMEM;
 148 
 149         sd = &state->sd;
 150         v4l2_i2c_subdev_init(sd, client, &m52790_ops);
 151         state->input = M52790_IN_TUNER;
 152         state->output = M52790_OUT_STEREO;
 153         m52790_write(sd);
 154         return 0;
 155 }
 156 
 157 static int m52790_remove(struct i2c_client *client)
 158 {
 159         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 160 
 161         v4l2_device_unregister_subdev(sd);
 162         return 0;
 163 }
 164 
 165 /* ----------------------------------------------------------------------- */
 166 
 167 static const struct i2c_device_id m52790_id[] = {
 168         { "m52790", 0 },
 169         { }
 170 };
 171 MODULE_DEVICE_TABLE(i2c, m52790_id);
 172 
 173 static struct i2c_driver m52790_driver = {
 174         .driver = {
 175                 .name   = "m52790",
 176         },
 177         .probe          = m52790_probe,
 178         .remove         = m52790_remove,
 179         .id_table       = m52790_id,
 180 };
 181 
 182 module_i2c_driver(m52790_driver);