Re: [PATCH v5 6/9] hwmon: (tmp421) support HWMON_T_ENABLE

[Guenter Roeck <linux@roeck-us.net>]

On Thu, Oct 14, 2021 at 03:09:58PM +0200, Krzysztof Adamski wrote:
> Since the recent patches added possibility of disabling sensor channels
> via DT, it only make sense to allow controlling that from userspace via
> HWMON_T_ENABLE mechanism. This patches adds support for that.
> 
> Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>

Applied, with the usual fixup.

Guenter

> ---
>  drivers/hwmon/tmp421.c | 33 +++++++++++++++++++++++++++++----
>  1 file changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
> index b402e81ae5d5..2e20c558fcb0 100644
> --- a/drivers/hwmon/tmp421.c
> +++ b/drivers/hwmon/tmp421.c
> @@ -203,21 +203,25 @@ static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
>  	if (ret)
>  		return ret;
>  
> -	if (!tmp421->channel[channel].enabled)
> -		return -ENODATA;
> -
>  	switch (attr) {
>  	case hwmon_temp_input:
> +		if (!tmp421->channel[channel].enabled)
> +			return -ENODATA;
>  		*val = temp_from_raw(tmp421->channel[channel].temp,
>  				     tmp421->config & TMP421_CONFIG_RANGE);
>  		return 0;
>  	case hwmon_temp_fault:
> +		if (!tmp421->channel[channel].enabled)
> +			return -ENODATA;
>  		/*
>  		 * Any of OPEN or /PVLD bits indicate a hardware mulfunction
>  		 * and the conversion result may be incorrect
>  		 */
>  		*val = !!(tmp421->channel[channel].temp & 0x03);
>  		return 0;
> +	case hwmon_temp_enable:
> +		*val = tmp421->channel[channel].enabled;
> +		return 0;
>  	default:
>  		return -EOPNOTSUPP;
>  	}
> @@ -234,6 +238,24 @@ static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type,
>  	return 0;
>  }
>  
> +static int tmp421_write(struct device *dev, enum hwmon_sensor_types type,
> +			u32 attr, int channel, long val)
> +{
> +	struct tmp421_data *data = dev_get_drvdata(dev);
> +	int ret;
> +
> +	switch (attr) {
> +	case hwmon_temp_enable:
> +		data->channel[channel].enabled = val;
> +		ret = tmp421_enable_channels(data);
> +		break;
> +	default:
> +	    ret = -EOPNOTSUPP;
> +	}
> +
> +	return ret;
> +}
> +
>  static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
>  				 u32 attr, int channel)
>  {
> @@ -243,6 +265,8 @@ static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
>  		return 0444;
>  	case hwmon_temp_label:
>  		return 0444;
> +	case hwmon_temp_enable:
> +		return 0644;
>  	default:
>  		return 0;
>  	}
> @@ -402,6 +426,7 @@ static const struct hwmon_ops tmp421_ops = {
>  	.is_visible = tmp421_is_visible,
>  	.read = tmp421_read,
>  	.read_string = tmp421_read_string,
> +	.write = tmp421_write,
>  };
>  
>  static int tmp421_probe(struct i2c_client *client)
> @@ -424,7 +449,7 @@ static int tmp421_probe(struct i2c_client *client)
>  	data->client = client;
>  
>  	for (i = 0; i < data->channels; i++) {
> -		data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT;
> +		data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_ENABLE;
>  		data->channel[i].enabled = true;
>  	}
>