Subject: [PATCH v4 2/8] thermal: qcom: tsens-8916: Add support for 8916 family of SoCs

From: [email-masked] (Rajendra Nayak)
Date: Thu, 05 Nov 2015 12:40:18 +0530

On 11/03/2015 02:12 AM, Eduardo Valentin wrote:
> On Fri, Oct 09, 2015 at 03:11:04PM +0530, Rajendra Nayak wrote:
>> Add support to calibrate sensors on 8916 family and also add common
>> functions to read temperature from sensors (This can be reused on
>> other SoCs having similar TSENS device)
>> The calibration data is read from eeprom using the generic nvmem
>> framework apis.
>>
>> Based on the original code by Siddartha Mohanadoss and Stephen Boyd.
>>
>> Signed-off-by: Rajendra Nayak <[email-masked]>
>> ---
>>  drivers/thermal/qcom/Makefile       |   2 +-
>>  drivers/thermal/qcom/tsens-8916.c   | 107 +++++++++++++++++++++++++++++
>>  drivers/thermal/qcom/tsens-common.c | 130 ++++++++++++++++++++++++++++++++++++
> 
> Just a small comment on organization, does it make sense to move tsens-common
> addition to the first patch, and then leave this patch only with the
> support for 8916 (like you did for the other chips)?

So the common code gets used for 8916 and hence I added it here as part of this patch.
I can as well move it to the first patch in the series, should not be an issue.

> 
>>  drivers/thermal/qcom/tsens.c        |   1 +
>>  drivers/thermal/qcom/tsens.h        |  11 +++
>>  5 files changed, 250 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/thermal/qcom/tsens-8916.c
>>  create mode 100644 drivers/thermal/qcom/tsens-common.c
>>
>> diff --git a/drivers/thermal/qcom/Makefile b/drivers/thermal/qcom/Makefile
>> index 401069b..05c98e4 100644
>> --- a/drivers/thermal/qcom/Makefile
>> +++ b/drivers/thermal/qcom/Makefile
>> @@ -1,2 +1,2 @@
>>  obj-$(CONFIG_QCOM_TSENS)	+= qcom_tsens.o
>> -qcom_tsens-y			+= tsens.o
>> +qcom_tsens-y			+= tsens.o tsens-common.o tsens-8916.o
>> diff --git a/drivers/thermal/qcom/tsens-8916.c b/drivers/thermal/qcom/tsens-8916.c
>> new file mode 100644
>> index 0000000..a69aea3
>> --- /dev/null
>> +++ b/drivers/thermal/qcom/tsens-8916.c
>> @@ -0,0 +1,107 @@
>> +/*
>> + * Copyright (c) 2015, The Linux Foundation. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 and
>> + * only version 2 as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + */
>> +
>> +#include <linux/platform_device.h>
>> +#include "tsens.h"
>> +
>> +/* eeprom layout data for 8916 */
>> +#define BASE0_MASK	0x0000007f
>> +#define BASE1_MASK	0xfe000000
>> +#define BASE0_SHIFT	0
>> +#define BASE1_SHIFT	25
>> +
>> +#define S0_P1_MASK	0x00000f80
>> +#define S1_P1_MASK	0x003e0000
>> +#define S2_P1_MASK	0xf8000000
>> +#define S3_P1_MASK	0x000003e0
>> +#define S4_P1_MASK	0x000f8000
>> +
>> +#define S0_P2_MASK	0x0001f000
>> +#define S1_P2_MASK	0x07c00000
>> +#define S2_P2_MASK	0x0000001f
>> +#define S3_P2_MASK	0x00007c00
>> +#define S4_P2_MASK	0x01f00000
>> +
>> +#define S0_P1_SHIFT	7
>> +#define S1_P1_SHIFT	17
>> +#define S2_P1_SHIFT	27
>> +#define S3_P1_SHIFT	5
>> +#define S4_P1_SHIFT	15
>> +
>> +#define S0_P2_SHIFT	12
>> +#define S1_P2_SHIFT	22
>> +#define S2_P2_SHIFT	0
>> +#define S3_P2_SHIFT	10
>> +#define S4_P2_SHIFT	20
>> +
>> +#define CAL_SEL_MASK	0xe0000000
>> +#define CAL_SEL_SHIFT	29
>> +
>> +static int calibrate_8916(struct tsens_device *tmdev)
>> +{
>> +	int base0 = 0, base1 = 0, i;
>> +	u32 p1[5], p2[5];
>> +	int mode = 0;
>> +	u32 *qfprom_cdata, *qfprom_csel;
>> +
>> +	qfprom_cdata = (u32 *)qfprom_read(tmdev->dev, "calib");
>> +	if (IS_ERR(qfprom_cdata))
>> +		return PTR_ERR(qfprom_cdata);
>> +
>> +	qfprom_csel = (u32 *)qfprom_read(tmdev->dev, "calib_sel");
>> +	if (IS_ERR(qfprom_csel))
>> +		return PTR_ERR(qfprom_csel);
>> +
>> +	mode = (qfprom_csel[0] & CAL_SEL_MASK) >> CAL_SEL_SHIFT;
>> +	dev_dbg(tmdev->dev, "calibration mode is %d\n", mode);
>> +
>> +	switch (mode) {
>> +	case TWO_PT_CALIB:
>> +		base1 = (qfprom_cdata[1] & BASE1_MASK) >> BASE1_SHIFT;
>> +		p2[0] = (qfprom_cdata[0] & S0_P2_MASK) >> S0_P2_SHIFT;
>> +		p2[1] = (qfprom_cdata[0] & S1_P2_MASK) >> S1_P2_SHIFT;
>> +		p2[2] = (qfprom_cdata[1] & S2_P2_MASK) >> S2_P2_SHIFT;
>> +		p2[3] = (qfprom_cdata[1] & S3_P2_MASK) >> S3_P2_SHIFT;
>> +		p2[4] = (qfprom_cdata[1] & S4_P2_MASK) >> S4_P2_SHIFT;
>> +		for (i = 0; i < tmdev->num_sensors; i++)
>> +			p2[i] = ((base1 + p2[i]) << 3);
>> +		/* Fall through */
>> +	case ONE_PT_CALIB2:
>> +		base0 = (qfprom_cdata[0] & BASE0_MASK);
>> +		p1[0] = (qfprom_cdata[0] & S0_P1_MASK) >> S0_P1_SHIFT;
>> +		p1[1] = (qfprom_cdata[0] & S1_P1_MASK) >> S1_P1_SHIFT;
>> +		p1[2] = (qfprom_cdata[0] & S2_P1_MASK) >> S2_P1_SHIFT;
>> +		p1[3] = (qfprom_cdata[1] & S3_P1_MASK) >> S3_P1_SHIFT;
>> +		p1[4] = (qfprom_cdata[1] & S4_P1_MASK) >> S4_P1_SHIFT;
>> +		for (i = 0; i < tmdev->num_sensors; i++)
>> +			p1[i] = (((base0) + p1[i]) << 3);
>> +		break;
>> +	default:
>> +		for (i = 0; i < tmdev->num_sensors; i++) {
>> +			p1[i] = 500;
>> +			p2[i] = 780;
>> +		}
>> +		break;
>> +	}
>> +
>> +	compute_intercept_slope(tmdev, p1, p2, mode);
>> +
>> +	return 0;
> 
> Can calibration fail ? In which cases?

yes, it can if the eeprom reads fail for instance.

> 
>> +}
>> +
>> +const struct tsens_ops ops_8916 = {
>> +	.init		= init_common,
>> +	.calibrate	= calibrate_8916,
>> +	.get_temp	= get_temp_common,
>> +};
>> diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
>> new file mode 100644
>> index 0000000..4acf52c
>> --- /dev/null
>> +++ b/drivers/thermal/qcom/tsens-common.c
>> @@ -0,0 +1,130 @@
>> +/*
>> + * Copyright (c) 2015, The Linux Foundation. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 and
>> + * only version 2 as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + */
>> +
>> +#include <linux/platform_device.h>
>> +#include <linux/nvmem-consumer.h>
>> +#include <linux/err.h>
>> +#include <linux/io.h>
>> +#include <linux/of_address.h>
>> +#include <linux/regmap.h>
>> +#include "tsens.h"
>> +
>> +#define S0_ST_ADDR		0x1030
>> +#define SN_ADDR_OFFSET		0x4
>> +#define SN_ST_TEMP_MASK		0x3ff
>> +#define CAL_DEGC_PT1		30
>> +#define CAL_DEGC_PT2		120
>> +#define SLOPE_FACTOR		1000
>> +
>> +char *qfprom_read(struct device *dev, const char *cname)
>> +{
>> +	struct nvmem_cell *cell;
>> +	ssize_t data;
>> +	char *ret;
>> +
>> +	cell = nvmem_cell_get(dev, cname);
>> +	if (IS_ERR(cell))
>> +		return ERR_CAST(cell);
>> +
>> +	ret = nvmem_cell_read(cell, &data);
>> +	nvmem_cell_put(cell);
> nip: add a blank line here.
>> +	return ret;
>> +}
>> +
>> +void compute_intercept_slope(struct tsens_device *tmdev, u32 *p1,
>> +			     u32 *p2, u32 mode)
>> +{
>> +	int i;
>> +	int num, den;
>> +
>> +	for (i = 0; i < tmdev->num_sensors; i++) {
>> +		dev_dbg(tmdev->dev,
>> +			"sensor%d - data_point1:%#x data_point2:%#x\n",
>> +			i, p1[i], p2[i]);
>> +
>> +		if (mode == TWO_PT_CALIB) {
>> +			/*
>> +			 * slope (m) = adc_code2 - adc_code1 (y2 - y1)/
>> +			 *	temp_120_degc - temp_30_degc (x2 - x1)
>> +			 */
>> +			num = p2[i] - p1[i];
>> +			num *= SLOPE_FACTOR;
>> +			den = CAL_DEGC_PT2 - CAL_DEGC_PT1;
>> +			tmdev->sensor[i].slope = num / den;
>> +		}
>> +
>> +		tmdev->sensor[i].offset = (p1[i] * SLOPE_FACTOR) -
>> +				(CAL_DEGC_PT1 *
>> +				tmdev->sensor[i].slope);
>> +		dev_dbg(tmdev->dev, "offset:%d\n", tmdev->sensor[i].offset);
>> +	}
>> +}
>> +
>> +static inline int code_to_degc(u32 adc_code, const struct tsens_sensor *s)
>> +{
>> +	int degc, num, den;
>> +
>> +	num = (adc_code * SLOPE_FACTOR) - s->offset;
>> +	den = s->slope;
>> +
>> +	if (num > 0)
>> +		degc = num + (den / 2);
>> +	else if (num < 0)
>> +		degc = num - (den / 2);
>> +	else
>> +		degc = num;
>> +
>> +	degc /= den;
>> +
>> +	return degc;
>> +}
>> +
>> +int get_temp_common(struct tsens_device *tmdev, int id, int *temp)
>> +{
>> +	struct tsens_sensor *s = &tmdev->sensor[id];
>> +	u32 code;
>> +	unsigned int sensor_addr;
>> +	int last_temp = 0, ret;
>> +
>> +	sensor_addr = S0_ST_ADDR + s->hw_id * SN_ADDR_OFFSET;
>> +	ret = regmap_read(tmdev->map, sensor_addr, &code);
>> +	if (ret)
>> +		return ret;
>> +	last_temp = code & SN_ST_TEMP_MASK;
>> +
>> +	*temp = code_to_degc(last_temp, s) * 1000;
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct regmap_config tsens_config = {
>> +	.reg_bits	= 32,
>> +	.val_bits	= 32,
>> +	.reg_stride	= 4,
>> +};
>> +
>> +int init_common(struct tsens_device *tmdev)
>> +{
>> +	void __iomem *base;
>> +
>> +	base = of_iomap(tmdev->dev->of_node, 0);
>> +	if (IS_ERR(base))
>> +		return -EINVAL;
>> +
>> +	tmdev->map = devm_regmap_init_mmio(tmdev->dev, base, &tsens_config);
> 
> Should this function be marked as __init so devm_* works?
> 
>> +	if (!tmdev->map)
>> +		return -ENODEV;
> 
> Should you do iounmap?

yes, will fix these.
thanks,
Rajendra

> 
>> +
>> +	return 0;
>> +}
>> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
>> index 87f5215..3d49293 100644
>> --- a/drivers/thermal/qcom/tsens.c
>> +++ b/drivers/thermal/qcom/tsens.c
>> @@ -65,6 +65,7 @@ static SIMPLE_DEV_PM_OPS(tsens_pm_ops, tsens_suspend, tsens_resume);
>>  static const struct of_device_id tsens_table[] = {
>>  	{
>>  		.compatible = "qcom,msm8916-tsens",
>> +		.data = &ops_8916,
>>  	}, {
>>  		.compatible = "qcom,msm8974-tsens",
>>  	},
>> diff --git a/drivers/thermal/qcom/tsens.h b/drivers/thermal/qcom/tsens.h
>> index f0fc353..0923822 100644
>> --- a/drivers/thermal/qcom/tsens.h
>> +++ b/drivers/thermal/qcom/tsens.h
>> @@ -13,6 +13,10 @@
>>  #ifndef __QCOM_TSENS_H__
>>  #define __QCOM_TSENS_H__
>>  
>> +#define ONE_PT_CALIB		0x1
>> +#define ONE_PT_CALIB2		0x2
>> +#define TWO_PT_CALIB		0x3
>> +
>>  struct tsens_device;
>>  
>>  struct tsens_sensor {
>> @@ -55,4 +59,11 @@ struct tsens_device {
>>  	struct tsens_sensor		sensor[0];
>>  };
>>  
>> +char *qfprom_read(struct device *, const char *);
>> +void compute_intercept_slope(struct tsens_device *, u32 *, u32 *, u32);
>> +int init_common(struct tsens_device *);
>> +int get_temp_common(struct tsens_device *, int, int *);
>> +
>> +extern const struct tsens_ops ops_8916;
>> +
>>  #endif /* __QCOM_TSENS_H__ */
>> -- 
>> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
>> of Code Aurora Forum, hosted by The Linux Foundation
>>

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation