target/linux/apm821xx/patches-5.4/803-hwmon-tc654-add-detection-routine.patch

   1 From 694f9bfb8efaef8a33e8992015ff9d0866faf4a2 Mon Sep 17 00:00:00 2001
   2 From: Christian Lamparter <chunkeey@gmail.com>
   3 Date: Sun, 17 Dec 2017 17:27:15 +0100
   4 Subject: [PATCH 1/2] hwmon: tc654 add detection routine
   5
   6 This patch adds a detection routine for the TC654/TC655
   7 chips.  Both IDs are listed in the Datasheet.
   8
   9 Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
  10 ---
  11  drivers/hwmon/tc654.c | 29 +++++++++++++++++++++++++++++
  12  1 file changed, 29 insertions(+)
  13
  14 --- a/drivers/hwmon/tc654.c
  15 +++ b/drivers/hwmon/tc654.c
  16 @@ -55,6 +55,11 @@ enum tc654_regs {
  17  /* Register data is read (and cached) at most once per second. */
  18  #define TC654_UPDATE_INTERVAL          HZ
  19
  20 +/* Manufacturer and Version Identification Register Values */
  21 +#define TC654_MFR_ID_MICROCHIP         0x84
  22 +#define TC654_VER_ID                   0x00
  23 +#define TC655_VER_ID                   0x01
  24 +
  25  struct tc654_data {
  26         struct i2c_client *client;
  27
  28 @@ -482,6 +487,29 @@ static const struct i2c_device_id tc654_
  29         {}
  30  };
  31
  32 +static int
  33 +tc654_detect(struct i2c_client *new_client, struct i2c_board_info *info)
  34 +{
  35 +       struct i2c_adapter *adapter = new_client->adapter;
  36 +       int manufacturer, product;
  37 +
  38 +       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
  39 +               return -ENODEV;
  40 +
  41 +       manufacturer = i2c_smbus_read_byte_data(new_client, TC654_REG_MFR_ID);
  42 +       if (manufacturer != TC654_MFR_ID_MICROCHIP)
  43 +               return -ENODEV;
  44 +
  45 +       product = i2c_smbus_read_byte_data(new_client, TC654_REG_VER_ID);
  46 +       if (!((product == TC654_VER_ID) || (product == TC655_VER_ID)))
  47 +               return -ENODEV;
  48 +
  49 +       strlcpy(info->type, product == TC654_VER_ID ? "tc654" : "tc655",
  50 +               I2C_NAME_SIZE);
  51 +       return 0;
  52 +}
  53 +
  54 +
  55  MODULE_DEVICE_TABLE(i2c, tc654_id);
  56
  57  static struct i2c_driver tc654_driver = {
  58 @@ -490,6 +518,7 @@ static struct i2c_driver tc654_driver =
  59                    },
  60         .probe = tc654_probe,
  61         .id_table = tc654_id,
  62 +       .detect = tc654_detect,
  63  };
  64
  65  module_i2c_driver(tc654_driver);