Re: [PATCH v5 09/20] thermal/drivers/tsens: Support using nvmem cells for calibration data

[Konrad Dybcio <konrad.dybcio@linaro.org>]

On 29.12.2022 12:52, Dmitry Baryshkov wrote:
> On Thu, 29 Dec 2022 at 13:47, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>> On 29.12.2022 12:42, Dmitry Baryshkov wrote:
>>> On Thu, 29 Dec 2022 at 12:47, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>>>> On 29.12.2022 04:00, Dmitry Baryshkov wrote:
>>>>> Add a unified function using nvmem cells for parsing the calibration
>>>>> data rather than parsing the calibration blob manually.
>>>>>
>>>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>>> ---
>>>>>  drivers/thermal/qcom/tsens-v0_1.c | 15 ++++++
>>>>>  drivers/thermal/qcom/tsens-v1.c   | 11 ++++-
>>>>>  drivers/thermal/qcom/tsens.c      | 76 +++++++++++++++++++++++++++++++
>>>>>  drivers/thermal/qcom/tsens.h      |  5 ++
>>>>>  4 files changed, 106 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/thermal/qcom/tsens-v0_1.c b/drivers/thermal/qcom/tsens-v0_1.c
>>>>> index 579028ea48f4..6c9e491f9559 100644
>>>>> --- a/drivers/thermal/qcom/tsens-v0_1.c
>>>>> +++ b/drivers/thermal/qcom/tsens-v0_1.c
>>>>> @@ -229,6 +229,11 @@ static int calibrate_8916(struct tsens_priv *priv)
>>>>>       u32 p1[5], p2[5];
>>>>>       int mode = 0;
>>>>>       u32 *qfprom_cdata, *qfprom_csel;
>>>>> +     int ret;
>>>>> +
>>>>> +     ret = tsens_calibrate_nvmem(priv, 3);
>>>>> +     if (!ret)
>>>>> +             return 0;
>>>>>
>>>>>       qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>>>>>       if (IS_ERR(qfprom_cdata))
>>>>> @@ -286,6 +291,11 @@ static int calibrate_8939(struct tsens_priv *priv)
>>>>>       int mode = 0;
>>>>>       u32 *qfprom_cdata;
>>>>>       u32 cdata[4];
>>>>> +     int ret;
>>>>> +
>>>>> +     ret = tsens_calibrate_common(priv);
>>>>> +     if (!ret)
>>>>> +             return 0;
>>>>>
>>>>>       qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>>>>>       if (IS_ERR(qfprom_cdata))
>>>>> @@ -486,6 +496,11 @@ static int calibrate_9607(struct tsens_priv *priv)
>>>>>       u32 p1[5], p2[5];
>>>>>       int mode = 0;
>>>>>       u32 *qfprom_cdata;
>>>>> +     int ret;
>>>>> +
>>>>> +     ret = tsens_calibrate_common(priv);
>>>>> +     if (!ret)
>>>>> +             return 0;
>>>>>
>>>>>       qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>>>>>       if (IS_ERR(qfprom_cdata))
>>>>> diff --git a/drivers/thermal/qcom/tsens-v1.c b/drivers/thermal/qcom/tsens-v1.c
>>>>> index 83c2853546d0..5bba75a845c5 100644
>>>>> --- a/drivers/thermal/qcom/tsens-v1.c
>>>>> +++ b/drivers/thermal/qcom/tsens-v1.c
>>>>> @@ -143,7 +143,11 @@ static int calibrate_v1(struct tsens_priv *priv)
>>>>>       u32 p1[10], p2[10];
>>>>>       u32 mode = 0, lsb = 0, msb = 0;
>>>>>       u32 *qfprom_cdata;
>>>>> -     int i;
>>>>> +     int i, ret;
>>>>> +
>>>>> +     ret = tsens_calibrate_common(priv);
>>>>> +     if (!ret)
>>>>> +             return 0;
>>>>>
>>>>>       qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>>>>>       if (IS_ERR(qfprom_cdata))
>>>>> @@ -209,6 +213,11 @@ static int calibrate_8976(struct tsens_priv *priv)
>>>>>       u32 p1[11], p2[11];
>>>>>       int mode = 0, tmp = 0;
>>>>>       u32 *qfprom_cdata;
>>>>> +     int ret;
>>>>> +
>>>>> +     ret = tsens_calibrate_common(priv);
>>>>> +     if (!ret)
>>>>> +             return 0;
>>>>>
>>>>>       qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>>>>>       if (IS_ERR(qfprom_cdata))
>>>>> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
>>>>> index b191e19df93d..ce568a68de4a 100644
>>>>> --- a/drivers/thermal/qcom/tsens.c
>>>>> +++ b/drivers/thermal/qcom/tsens.c
>>>>> @@ -70,6 +70,82 @@ char *qfprom_read(struct device *dev, const char *cname)
>>>>>       return ret;
>>>>>  }
>>>>>
>>>>> +int tsens_calibrate_nvmem(struct tsens_priv *priv, int shift)
>>>>> +{
>>>>> +     u32 mode;
>>>>> +     u32 base1, base2;
>>>>> +     u32 p1[MAX_SENSORS], p2[MAX_SENSORS];
>>>>> +     char name[] = "sXX_pY"; /* s10_p1 */
>>>>> +     int i, ret;
>>>>> +
>>>>> +     if (priv->num_sensors > MAX_SENSORS)
>>>>> +             return -EINVAL;
>>>>> +
>>>>> +     ret = nvmem_cell_read_variable_le_u32(priv->dev, "mode", &mode);
>>>>> +     if (ret == -ENOENT)
>>>>> +             dev_warn(priv->dev, "Please migrate to separate nvmem cells for calibration data\n");
>>>>> +     if (ret < 0)
>>>>> +             return ret;
>>>>> +
>>>>> +     dev_dbg(priv->dev, "calibration mode is %d\n", mode);
>>>>> +
>>>>> +     ret = nvmem_cell_read_variable_le_u32(priv->dev, "base1", &base1);
>>>>> +     if (ret < 0)
>>>>> +             return ret;
>>>>> +
>>>>> +     ret = nvmem_cell_read_variable_le_u32(priv->dev, "base2", &base2);
>>>>> +     if (ret < 0)
>>>>> +             return ret;
>>>>> +
>>>>> +     for (i = 0; i < priv->num_sensors; i++) {
>>>>> +             ret = snprintf(name, sizeof(name), "s%d_p1", priv->sensor[i].hw_id);
>>>> I think you forgot to update the underscore to a hyphen here
>>>> (unless the nvmem api does some magic internally).
>>>
>>> No. Please see the nvmem-cell-names property of the tsens nodes. It
>>> uses underscores. Then OF code translates this sX_pY string into an
>>> index in the nvmem-cells array or phandles. The sX-pY@ZZ node name is
>>> not used during lookups at all.
>> Right, I overlooked that!
>>
>>>
>>>>
>>>> Konrad
>>>>> +             if (ret < 0)
>>>>> +                     return ret;
>>>>> +
>>>>> +             ret = nvmem_cell_read_variable_le_u32(priv->dev, name, &p1[i]);
>>>>> +             if (ret)
>>>>> +                     return ret;
>>>>> +
>>>>> +             ret = snprintf(name, sizeof(name), "s%d_p2", priv->sensor[i].hw_id);
>>>>> +             if (ret < 0)
>>>>> +                     return ret;
>>>>> +
>>>>> +             ret = nvmem_cell_read_variable_le_u32(priv->dev, name, &p2[i]);
>>>>> +             if (ret)
>>>>> +                     return ret;
>>>>> +     }
>>>>> +
>>>>> +     switch (mode) {
>>>>> +     case ONE_PT_CALIB:
>>>>> +             for (i = 0; i < priv->num_sensors; i++)
>>>>> +                     p1[i] = p1[i] + (base1 << shift);
>>>>> +             break;
>>>>> +     case TWO_PT_CALIB:
>>>>> +             for (i = 0; i < priv->num_sensors; i++)
>>>>> +                     p2[i] = (p2[i] + base2) << shift;
>>>>> +             fallthrough;
>>>>> +     case ONE_PT_CALIB2:
>>>>> +             for (i = 0; i < priv->num_sensors; i++)
>>>>> +                     p1[i] = (p1[i] + base1) << shift;
>>>>> +             break;
>>>>> +     default:
>>>>> +             dev_dbg(priv->dev, "calibrationless mode\n");
>> This could be a dev_warn, as we usually don't expect it to happen.
> 
> I'm not so sure here. Current code handles this case without any
> warnings, as one of the expected cases So, I don't think the rework
> should start emitting warnings.
Right, perhaps that's something to consider at a different time.

Konrad
> 
>> Other than that:
>>
>> Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>>
>> Konrad
>>>>> +             for (i = 0; i < priv->num_sensors; i++) {
>>>>> +                     p1[i] = 500;
>>>>> +                     p2[i] = 780;
>>>>> +             }
>>>>> +     }
>>>>> +
>>>>> +     compute_intercept_slope(priv, p1, p2, mode);
>>>>> +
>>>>> +     return 0;
>>>>> +}
>>>>> +
>>>>> +int tsens_calibrate_common(struct tsens_priv *priv)
>>>>> +{
>>>>> +     return tsens_calibrate_nvmem(priv, 2);
>>>>> +}
>>>>> +
>>>>>  /*
>>>>>   * Use this function on devices where slope and offset calculations
>>>>>   * depend on calibration data read from qfprom. On others the slope
>>>>> diff --git a/drivers/thermal/qcom/tsens.h b/drivers/thermal/qcom/tsens.h
>>>>> index 7dd5fc246894..645ae02438fa 100644
>>>>> --- a/drivers/thermal/qcom/tsens.h
>>>>> +++ b/drivers/thermal/qcom/tsens.h
>>>>> @@ -6,6 +6,7 @@
>>>>>  #ifndef __QCOM_TSENS_H__
>>>>>  #define __QCOM_TSENS_H__
>>>>>
>>>>> +#define NO_PT_CALIB          0x0
>>>>>  #define ONE_PT_CALIB         0x1
>>>>>  #define ONE_PT_CALIB2                0x2
>>>>>  #define TWO_PT_CALIB         0x3
>>>>> @@ -17,6 +18,8 @@
>>>>>  #define THRESHOLD_MAX_ADC_CODE       0x3ff
>>>>>  #define THRESHOLD_MIN_ADC_CODE       0x0
>>>>>
>>>>> +#define MAX_SENSORS 16
>>>>> +
>>>>>  #include <linux/interrupt.h>
>>>>>  #include <linux/thermal.h>
>>>>>  #include <linux/regmap.h>
>>>>> @@ -582,6 +585,8 @@ struct tsens_priv {
>>>>>  };
>>>>>
>>>>>  char *qfprom_read(struct device *dev, const char *cname);
>>>>> +int tsens_calibrate_nvmem(struct tsens_priv *priv, int shift);
>>>>> +int tsens_calibrate_common(struct tsens_priv *priv);
>>>>>  void compute_intercept_slope(struct tsens_priv *priv, u32 *pt1, u32 *pt2, u32 mode);
>>>>>  int init_common(struct tsens_priv *priv);
>>>>>  int get_temp_tsens_valid(const struct tsens_sensor *s, int *temp);
>>>
>>>
>>>
> 
> 
>