[v7, 3/3] thermal: mediatek: add another get_temp ops for thermal sensors

[Michael Kao]

Hi Maintainers,

Gentle pin for this patch.

Thanks

On Tue, 2021-03-16 at 15:01 +0800, Michael Kao wrote:
> Provide thermal zone to read thermal sensor
> in the SoC. We can read all the thermal sensors
> value in the SoC by the node /sys/class/thermal/
> 
> In mtk_thermal_bank_temperature, return -EAGAIN instead of -EACCESS
> on the first read of sensor that often are bogus values.
> This can avoid following warning on boot:
> 
>   thermal thermal_zone6: failed to read out thermal zone (-13)
> 
> Signed-off-by: Michael Kao <michael.kao at mediatek.com>
> Signed-off-by: Hsin-Yi Wang <hsinyi at chromium.org>
> ---
>  drivers/thermal/mtk_thermal.c | 100 +++++++++++++++++++++++++---------
>  1 file changed, 75 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/thermal/mtk_thermal.c b/drivers/thermal/mtk_thermal.c
> index 149c6d7fd5a0..57e4f08a947e 100644
> --- a/drivers/thermal/mtk_thermal.c
> +++ b/drivers/thermal/mtk_thermal.c
> @@ -245,6 +245,11 @@ enum mtk_thermal_version {
>  
>  struct mtk_thermal;
>  
> +struct mtk_thermal_zone {
> +	struct mtk_thermal *mt;
> +	int id;
> +};
> +
>  struct thermal_bank_cfg {
>  	unsigned int num_sensors;
>  	const int *sensors;
> @@ -637,6 +642,30 @@ static void mtk_thermal_put_bank(struct mtk_thermal_bank *bank)
>  		mutex_unlock(&mt->lock);
>  }
>  
> +static u32 _get_sensor_temp(struct mtk_thermal *mt, int id)
> +{
> +	u32 raw;
> +	int temp;
> +
> +	raw = readl(mt->thermal_base + mt->conf->msr[id]);
> +
> +	if (mt->conf->version == MTK_THERMAL_V1)
> +		temp = raw_to_mcelsius_v1(mt, id, raw);
> +	else
> +		temp = raw_to_mcelsius_v2(mt, id, raw);
> +
> +	/*
> +	 * The first read of a sensor often contains very high bogus
> +	 * temperature value. Filter these out so that the system does
> +	 * not immediately shut down.
> +	 */
> +
> +	if (temp > 200000)
> +		return -EAGAIN;
> +	else
> +		return temp;
> +}
> +
>  /**
>   * mtk_thermal_bank_temperature - get the temperature of a bank
>   * @bank:	The bank
> @@ -647,28 +676,11 @@ static void mtk_thermal_put_bank(struct mtk_thermal_bank *bank)
>  static int mtk_thermal_bank_temperature(struct mtk_thermal_bank *bank)
>  {
>  	struct mtk_thermal *mt = bank->mt;
> -	const struct mtk_thermal_data *conf = mt->conf;
>  	int i, temp = INT_MIN, max = INT_MIN;
> -	u32 raw;
> -
> -	for (i = 0; i < conf->bank_data[bank->id].num_sensors; i++) {
> -		raw = readl(mt->thermal_base + conf->msr[i]);
>  
> -		if (mt->conf->version == MTK_THERMAL_V1) {
> -			temp = raw_to_mcelsius_v1(
> -				mt, conf->bank_data[bank->id].sensors[i], raw);
> -		} else {
> -			temp = raw_to_mcelsius_v2(
> -				mt, conf->bank_data[bank->id].sensors[i], raw);
> -		}
> +	for (i = 0; i < mt->conf->bank_data[bank->id].num_sensors; i++) {
>  
> -		/*
> -		 * The first read of a sensor often contains very high bogus
> -		 * temperature value. Filter these out so that the system does
> -		 * not immediately shut down.
> -		 */
> -		if (temp > 200000)
> -			temp = 0;
> +		temp = _get_sensor_temp(mt, i);
>  
>  		if (temp > max)
>  			max = temp;
> @@ -679,7 +691,8 @@ static int mtk_thermal_bank_temperature(struct mtk_thermal_bank *bank)
>  
>  static int mtk_read_temp(void *data, int *temperature)
>  {
> -	struct mtk_thermal *mt = data;
> +	struct mtk_thermal_zone *tz = data;
> +	struct mtk_thermal *mt = tz->mt;
>  	int i;
>  	int tempmax = INT_MIN;
>  
> @@ -698,10 +711,28 @@ static int mtk_read_temp(void *data, int *temperature)
>  	return 0;
>  }
>  
> +static int mtk_read_sensor_temp(void *data, int *temperature)
> +{
> +	struct mtk_thermal_zone *tz = data;
> +	struct mtk_thermal *mt = tz->mt;
> +	int id = tz->id - 1;
> +
> +	if (id < 0)
> +		return -EACCES;
> +
> +	*temperature = _get_sensor_temp(mt, id);
> +
> +	return 0;
> +}
> +
>  static const struct thermal_zone_of_device_ops mtk_thermal_ops = {
>  	.get_temp = mtk_read_temp,
>  };
>  
> +static const struct thermal_zone_of_device_ops mtk_thermal_sensor_ops = {
> +	.get_temp = mtk_read_sensor_temp,
> +};
> +
>  static void mtk_thermal_init_bank(struct mtk_thermal *mt, int num,
>  				  u32 apmixed_phys_base, u32 auxadc_phys_base,
>  				  int ctrl_id)
> @@ -992,6 +1023,7 @@ static int mtk_thermal_probe(struct platform_device *pdev)
>  	u64 auxadc_phys_base, apmixed_phys_base;
>  	struct thermal_zone_device *tzdev;
>  	void __iomem *apmixed_base, *auxadc_base;
> +	struct mtk_thermal_zone *tz;
>  
>  	mt = devm_kzalloc(&pdev->dev, sizeof(*mt), GFP_KERNEL);
>  	if (!mt)
> @@ -1080,11 +1112,29 @@ static int mtk_thermal_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, mt);
>  
> -	tzdev = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, mt,
> -						     &mtk_thermal_ops);
> -	if (IS_ERR(tzdev)) {
> -		ret = PTR_ERR(tzdev);
> -		goto err_disable_clk_peri_therm;
> +	for (i = 0; i < mt->conf->num_sensors + 1; i++) {
> +		tz = devm_kmalloc(&pdev->dev, sizeof(*tz), GFP_KERNEL);
> +		if (!tz)
> +			return -ENOMEM;
> +
> +		tz->mt = mt;
> +		tz->id = i;
> +
> +		tzdev = devm_thermal_zone_of_sensor_register(&pdev->dev, i, tz, (i == 0) ?
> +							     &mtk_thermal_ops :
> +							     &mtk_thermal_sensor_ops);
> +
> +		if (IS_ERR(tzdev)) {
> +			if (PTR_ERR(tzdev) == -ENODEV) {
> +				dev_warn(&pdev->dev,
> +					 "sensor %d not registered in thermal zone in dt\n", i);
> +				continue;
> +			}
> +			if (PTR_ERR(tzdev) == -EACCES) {
> +				ret = PTR_ERR(tzdev);
> +				goto err_disable_clk_peri_therm;
> +			}
> +		}
>  	}
>  
>  	return 0;