On Thu, Oct 14, 2021 at 03:09:08PM +0200, Krzysztof Adamski wrote:
> Recent patch added possibility to disable selected channels. That would
> only make sure that the ENODATA is returned for those channels but would
> not configure the actual hardware.
>
> With this patch, the config register is written to make sure the
> channels are disabled also at hardware level.
>
> Signed-off-by: Krzysztof Adamski <krzysztof.adamski@xxxxxxxxx>
Applied, again after "s/^ / /"
Guenter
> ---
> drivers/hwmon/tmp421.c | 44 ++++++++++++++++++++++++++++++++++++------
> 1 file changed, 38 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
> index 606914f20910..b402e81ae5d5 100644
> --- a/drivers/hwmon/tmp421.c
> +++ b/drivers/hwmon/tmp421.c
> @@ -33,6 +33,9 @@ enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
> /* The TMP421 registers */
> #define TMP421_STATUS_REG 0x08
> #define TMP421_CONFIG_REG_1 0x09
> +#define TMP421_CONFIG_REG_2 0x0A
> +#define TMP421_CONFIG_REG_REN(x) (BIT(3 + (x)))
> +#define TMP421_CONFIG_REG_REN_MASK GENMASK(6, 3)
> #define TMP421_CONVERSION_RATE_REG 0x0B
> #define TMP421_N_FACTOR_REG_1 0x21
> #define TMP421_MANUFACTURER_ID_REG 0xFE
> @@ -162,6 +165,34 @@ static int tmp421_update_device(struct tmp421_data *data)
> return 0;
> }
>
> +static int tmp421_enable_channels(struct tmp421_data *data)
> +{
> + int err;
> + struct i2c_client *client = data->client;
> + struct device *dev = &client->dev;
> + int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2);
> + int new, i;
> +
> + if (old < 0) {
> + dev_err(dev, "error reading register, can't disable channels\n");
> + return old;
> + }
> +
> + new = old & ~TMP421_CONFIG_REG_REN_MASK;
> + for (i = 0; i < data->channels; i++)
> + if (data->channel[i].enabled)
> + new |= TMP421_CONFIG_REG_REN(i);
> +
> + if (new == old)
> + return 0;
> +
> + err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new);
> + if (err < 0)
> + dev_err(dev, "error writing register, can't disable channels\n");
> +
> + return err;
> +}
> +
> static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
> u32 attr, int channel, long *val)
> {
> @@ -217,9 +248,10 @@ static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
> }
> }
>
> -static int tmp421_init_client(struct i2c_client *client)
> +static int tmp421_init_client(struct tmp421_data *data)
> {
> int config, config_orig;
> + struct i2c_client *client = data->client;
>
> /* Set the conversion rate to 2 Hz */
> i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
> @@ -240,7 +272,7 @@ static int tmp421_init_client(struct i2c_client *client)
> i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
> }
>
> - return 0;
> + return tmp421_enable_channels(data);
> }
>
> static int tmp421_detect(struct i2c_client *client,
> @@ -391,10 +423,6 @@ static int tmp421_probe(struct i2c_client *client)
> data->channels = i2c_match_id(tmp421_id, client)->driver_data;
> data->client = client;
>
> - err = tmp421_init_client(client);
> - if (err)
> - return err;
> -
> for (i = 0; i < data->channels; i++) {
> data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT;
> data->channel[i].enabled = true;
> @@ -404,6 +432,10 @@ static int tmp421_probe(struct i2c_client *client)
> if (err)
> return err;
>
> + err = tmp421_init_client(data);
> + if (err)
> + return err;
> +
> data->chip.ops = &tmp421_ops;
> data->chip.info = data->info;
>
