diff mbox

[v3,1/2] thermal: Add qcom tsens thermal sensor driver

Message ID 1424760442-12564-2-git-send-email-nrajan@codeaurora.org (mailing list archive)
State Superseded, archived
Delegated to: Eduardo Valentin
Headers show

Commit Message

Narendran Rajan Feb. 24, 2015, 6:47 a.m. UTC
TSENS supports reading temperature from multiple thermal
sensors present in QCOM SOCs.
TSENS HW is enabled only when the main sensor is requested.
TSENS block is disabled if the main senors is disabled
irrespective of any other sensors that are being enabled

The driver needs calibration data which is read from qfprom.
Calibration data location is configured through dt files.

Based on code by Siddartha Mohanadoss and Stephen Boyd.

Cc: Siddartha Mohanadoss <smohanad@codeaurora.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Narendran Rajan <nrajan@codeaurora.org>
---
 .../devicetree/bindings/thermal/qcom-thermal.txt   |  59 +++
 drivers/thermal/Kconfig                            |  14 +
 drivers/thermal/Makefile                           |   1 +
 drivers/thermal/qcom-tsens.c                       | 493 +++++++++++++++++++++
 4 files changed, 567 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/thermal/qcom-thermal.txt
 create mode 100644 drivers/thermal/qcom-tsens.c

Comments

Eduardo Valentin Feb. 25, 2015, 7:44 p.m. UTC | #1
On Mon, Feb 23, 2015 at 10:47:21PM -0800, Narendran Rajan wrote:
> TSENS supports reading temperature from multiple thermal
> sensors present in QCOM SOCs.
> TSENS HW is enabled only when the main sensor is requested.
> TSENS block is disabled if the main senors is disabled
> irrespective of any other sensors that are being enabled
> 
> The driver needs calibration data which is read from qfprom.
> Calibration data location is configured through dt files.
> 
> Based on code by Siddartha Mohanadoss and Stephen Boyd.
> 
> Cc: Siddartha Mohanadoss <smohanad@codeaurora.org>
> Cc: Stephen Boyd <sboyd@codeaurora.org>
> Signed-off-by: Narendran Rajan <nrajan@codeaurora.org>
> ---
>  .../devicetree/bindings/thermal/qcom-thermal.txt   |  59 +++
>  drivers/thermal/Kconfig                            |  14 +
>  drivers/thermal/Makefile                           |   1 +
>  drivers/thermal/qcom-tsens.c                       | 493 +++++++++++++++++++++
>  4 files changed, 567 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/qcom-thermal.txt
>  create mode 100644 drivers/thermal/qcom-tsens.c
> 
> diff --git a/Documentation/devicetree/bindings/thermal/qcom-thermal.txt b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> new file mode 100644
> index 0000000..d513043
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> @@ -0,0 +1,59 @@
> +* QCOM SoC Temperature Sensor (TSENS)

Can you please add a brief description of this device and maybe a
pointer/reference to its documentation?


What are the current QCOM SoC supported? Or in which SoCs should we
expect to see TSENS in?

> +
> +Required properties:
> +- compatible : "qcom,qcom-tsens"
> +- qcom,tsens-slopes : Must contain slope value for each of the sensors controlled
> +			by this device
> +- qcom,qfprom : An array of triplets containing tsens calibration data.
> +		The first element in the triplet is a phandle
> +                to qfprom compatible node, second element is an offset to calibration
> +                data within this node, third element indicates size of calibration
> +                data. In general, there would be two elements in this array - the
> +                first containing information on primary calibration data
> +                and second containing information on backup calibration data
> +- qcom,qfprom-names : Names for each calibration data
> +- #thermal-sensor-cells : Should be 1. See ./thermal.txt for a description.
> +
> +Example:
> +
> +tsens: tsens-msm8960 {
> +		compatible = "qcom,qcom-tsens";
> +		qcom,tsens-slopes = <1176 1176 1154 1176 1111
> +				1132 1132 1199 1132 1199
> +				1132>;

Please use the thermal zone coefficients property here. Describing
slopes is possible with current thermal.txt descriptors.



> +		qcom,qfprom = <&imem 0x400 11>, <&imem 0x410 11>;
> +		qcom,qfprom-names = "calib", "backup_calib";
> +		#thermal-sensor-cells = <1>;
> +	};
> +
> +Example: referring to thermal sensors:
> +thermal-zones {
> +	cpu_thermal: cpu_thermal {
> +		polling-delay-passive = <1000>; /* milliseconds */
> +		polling-delay = <5000>; /* milliseconds */
> +
> +		/* sensor ID */
> +		thermal-sensors = <&tsens 1>;
> +
> +		trips {
> +			cpu_alert0: cpu_alert {
> +				temperature = <80000>; /* millicelsius */
> +				hysteresis = <2000>; /* millicelsius */
> +				type = "passive";
> +			};
> +			cpu_crit: cpu_crit {
> +				temperature = <120000>; /* millicelsius */
> +				hysteresis = <2000>; /* millicelsius */
> +				type = "critical";
> +			};
> +		};
> +
> +		cooling-maps {
> +			map0 {
> +				trip = <&cpu_alert0>;
> +				cooling-device =
> +					<&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +			};
> +		};
> +	};
> +};
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index af40db0..a57f1164 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -285,6 +285,20 @@ config ACPI_THERMAL_REL
>  	tristate
>  	depends on ACPI
>  
> +config THERMAL_QCOM_TSENS
> +	tristate "Qualcomm Tsens Temperature driver"
> +	depends on THERMAL
> +	depends on ARCH_QCOM
> +	help
> +	  QCOM tsens thermal driver provides support for Temperature sensor
> +	  (TSENS) found on QCOM SoCs. It supports four configurable trip points
> +	  and controls multiple sensors on the SOC. The four trip points are
> +	  common across all sensors present in the SoC. The number of sensors
> +	  present varies from chip to chip and are set through device tree entry.
> +	  The driver presents as a standard thermal zone device with configurable
> +	  trip points and cooling device mapping through standard thermal zone
> +	  device tree.

Should we assume this driver supports all QCOM SoCs?

> +
>  menu "Texas Instruments thermal drivers"
>  source "drivers/thermal/ti-soc-thermal/Kconfig"
>  endmenu
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index fa0dc48..3fdf6b9 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -39,3 +39,4 @@ obj-$(CONFIG_TI_SOC_THERMAL)	+= ti-soc-thermal/
>  obj-$(CONFIG_INT340X_THERMAL)  += int340x_thermal/
>  obj-$(CONFIG_ST_THERMAL)	+= st/
>  obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
> +obj-$(CONFIG_THERMAL_QCOMTSENS)	+= qcom-tsens.o
> diff --git a/drivers/thermal/qcom-tsens.c b/drivers/thermal/qcom-tsens.c
> new file mode 100644
> index 0000000..accc6a74
> --- /dev/null
> +++ b/drivers/thermal/qcom-tsens.c
> @@ -0,0 +1,493 @@
> +/* 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/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/thermal.h>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +#include <linux/err.h>
> +#include <linux/pm.h>
> +#include <linux/bitops.h>
> +#include <linux/regmap.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <soc/qcom/qfprom.h>
> +
> +#define TSENS_CAL_MDEGC                         30000
> +
> +#define TSENS_8960_CONFIG_ADDR                  0x3640
> +#define TSENS_8960_CONFIG                       0x9b
> +#define TSENS_8960_CONFIG_MASK                  0xff
> +
> +#define TSENS_CNTL_ADDR                         0x3620
> +#define TSENS_EN                                BIT(0)
> +#define TSENS_SW_RST                            BIT(1)
> +#define SENSOR0_EN                              BIT(3)
> +#define TSENS_MIN_STATUS_MASK                   BIT(0)
> +#define TSENS_LOWER_STATUS_CLR                  BIT(1)
> +#define TSENS_UPPER_STATUS_CLR                  BIT(2)
> +#define TSENS_MAX_STATUS_MASK                   BIT(3)
> +#define TSENS_8960_MEASURE_PERIOD               BIT(18)
> +#define TSENS_8660_MEASURE_PERIOD               BIT(16)
> +#define TSENS_8960_SLP_CLK_ENA                  BIT(26)
> +#define TSENS_8660_SLP_CLK_ENA                  BIT(24)
> +#define TSENS_8064_STATUS_CNTL                  0x3660
> +
> +#define TSENS_THRESHOLD_ADDR                    0x3624
> +#define TSENS_THRESHOLD_MAX_CODE                0xff
> +#define TSENS_THRESHOLD_MIN_CODE                0
> +#define TSENS_THRESHOLD_MAX_LIMIT_SHIFT         24
> +#define TSENS_THRESHOLD_MIN_LIMIT_SHIFT         16
> +#define TSENS_THRESHOLD_UPPER_LIMIT_SHIFT       8
> +#define TSENS_THRESHOLD_LOWER_LIMIT_SHIFT       0
> +
> +/* Initial temperature threshold values */
> +#define TSENS_LOWER_LIMIT_TH                    0x50
> +#define TSENS_UPPER_LIMIT_TH                    0xdf
> +#define TSENS_MIN_LIMIT_TH                      0x0
> +#define TSENS_MAX_LIMIT_TH                      0xff
> +
> +#define TSENS_S0_STATUS_ADDR                    0x3628
> +
> +#define TSENS_INT_STATUS_ADDR                   0x363c
> +#define TSENS_TRDY_MASK                         BIT(7)
> +
> +#define TSENS_SENSOR0_SHIFT                     3
> +
> +#define TSENS_8660_CONFIG                       1
> +#define TSENS_8660_CONFIG_SHIFT                 28
> +#define TSENS_8660_CONFIG_MASK                  (3 << TSENS_8660_CONFIG_SHIFT)
> +#define TSENS_SENSORABOVEFIVE_OFFSET            40
> +
> +struct tsens_device;
> +
> +struct tsens_sensor {
> +	struct thermal_zone_device	*tz_dev;
> +	enum thermal_device_mode	mode;
> +	unsigned int			sensor_num;
> +	int				offset;
> +	int				slope;
> +	struct tsens_device		*tmdev;
> +	u32                             status;
> +};
> +
> +struct tsens_device {
> +	struct device		*dev;
> +	bool			prev_reading_avail;
> +	unsigned int		num_sensors;
> +	int			pm_tsens_thr_data;
> +	int			pm_tsens_cntl;
> +	u32			slp_clk_enable;
> +	struct regmap		*map;
> +	struct regmap_field	*status_field;
> +	struct tsens_sensor	sensor[0];
> +};
> +
> +/* Temperature on y axis and ADC-code on x-axis */
> +static int
> +tsens_tz_code_to_mdegC(u32 adc_code, const struct tsens_sensor *s)
> +{
> +	return s->slope * adc_code + s->offset;
> +}
> +
> +static int tsens_tz_get_temp(void *_sensor,
> +			     long *temp)
> +{
> +	const struct tsens_sensor *tm_sensor = _sensor;
> +	struct tsens_device *tmdev = tm_sensor->tmdev;
> +	u32 code, trdy;
> +
> +	if (tm_sensor->mode != THERMAL_DEVICE_ENABLED)
> +		return -EINVAL;
> +
> +	if (!tmdev->prev_reading_avail) {
> +		while (!regmap_read(tmdev->map, TSENS_INT_STATUS_ADDR, &trdy) &&
> +		       !(trdy & TSENS_TRDY_MASK))
> +			usleep_range(1000, 1100);
> +		tmdev->prev_reading_avail = true;
> +	}
> +
> +	regmap_read(tmdev->map, tm_sensor->status, &code);
> +	*temp = tsens_tz_code_to_mdegC(code, tm_sensor);
> +
> +	tmdev->prev_reading_avail = false;
> +
> +	dev_dbg(tmdev->dev, "Sensor %d temp is: %ld",
> +		tm_sensor->sensor_num, *temp);
> +	return 0;
> +}
> +
> +/*
> + * If the main sensor is disabled, rest of the sensors are disabled
> + * along with the clock.
> + * If the main sensor is disabled and a sub-sensor is enabled
> + * return with an error.
> + */
> +static int tsens_tz_set_mode(struct tsens_sensor *tm_sensor,
> +			      enum thermal_device_mode mode)
> +{
> +	struct tsens_device *tmdev = tm_sensor->tmdev;
> +	unsigned int i, n = tmdev->num_sensors;
> +	u32 reg, mask;
> +
> +	if (mode == tm_sensor->mode)
> +		return 0;
> +
> +	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg);
> +
> +	mask = BIT(tm_sensor->sensor_num + TSENS_SENSOR0_SHIFT);
> +	if (mode == THERMAL_DEVICE_ENABLED) {
> +		if (!(reg & SENSOR0_EN) && mask != SENSOR0_EN) {
> +			dev_warn(tmdev->dev, "Main sensor not enabled\n");
> +			return -EINVAL;
> +		}
> +
> +		regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg | TSENS_SW_RST);
> +		reg |= mask | tmdev->slp_clk_enable | TSENS_EN;
> +
> +		tmdev->prev_reading_avail = false;
> +	} else {
> +		reg &= ~mask;
> +		if (!(reg & SENSOR0_EN)) {
> +			dev_warn(tmdev->dev, "Main sensor not enabled. Disabling subsensors\n");
> +
> +			reg &= ~GENMASK(n + TSENS_SENSOR0_SHIFT - 1,
> +					TSENS_SENSOR0_SHIFT);
> +			reg &= ~TSENS_EN;
> +
> +			reg &= ~tmdev->slp_clk_enable;
> +
> +			/* Disable all sub-sensors */
> +			for (i = 1; i < n; i++)
> +				tmdev->sensor[i].mode = mode;
> +		}
> +	}
> +
> +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg);
> +	tm_sensor->mode = mode;
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int tsens_suspend(struct device *dev)
> +{
> +	int i;
> +	unsigned int mask;
> +	struct tsens_device *tmdev = dev_get_drvdata(dev);
> +	struct regmap *map = tmdev->map;
> +
> +	regmap_read(map, TSENS_THRESHOLD_ADDR, &tmdev->pm_tsens_thr_data);
> +	regmap_read(map, TSENS_CNTL_ADDR, &tmdev->pm_tsens_cntl);
> +
> +	mask = tmdev->slp_clk_enable | TSENS_EN;
> +	regmap_update_bits(map, TSENS_CNTL_ADDR, mask, 0);
> +
> +	tmdev->prev_reading_avail = false;
> +	for (i = 0; i < tmdev->num_sensors; i++)
> +		tmdev->sensor[i].mode = THERMAL_DEVICE_DISABLED;
> +
> +	return 0;
> +}
> +
> +static int tsens_resume(struct device *dev)
> +{
> +	int i;
> +	unsigned long reg_cntl;
> +	struct tsens_device *tmdev = dev_get_drvdata(dev);
> +	struct regmap *map = tmdev->map;
> +
> +	regmap_update_bits(map, TSENS_CNTL_ADDR, TSENS_SW_RST, TSENS_SW_RST);
> +	regmap_field_update_bits(tmdev->status_field,
> +			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK,
> +			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK);
> +
> +	/*
> +	* Separate CONFIG restore is needed only for 8960. For 8660
> +	* config is part of CTRL Addr and its restored as such
> +	*/
> +	if (tmdev->num_sensors > 1)
> +		regmap_update_bits(map, TSENS_8960_CONFIG_ADDR,
> +				TSENS_8960_CONFIG_MASK,
> +				TSENS_8960_CONFIG);
> +
> +	regmap_write(map, TSENS_THRESHOLD_ADDR, tmdev->pm_tsens_thr_data);
> +	regmap_write(map, TSENS_CNTL_ADDR, tmdev->pm_tsens_cntl);
> +
> +	reg_cntl = tmdev->pm_tsens_cntl;
> +	reg_cntl >>= TSENS_SENSOR0_SHIFT;
> +	for_each_set_bit(i, &reg_cntl, tmdev->num_sensors)
> +		tmdev->sensor[i].mode = THERMAL_DEVICE_ENABLED;
> +
> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(tsens_pm_ops, tsens_suspend, tsens_resume);
> +#define TSENS_PM_OPS	(&tsens_pm_ops)
> +
> +#else /* CONFIG_PM_SLEEP */
> +
> +#define TSENS_PM_OPS	NULL
> +
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static void tsens_disable_mode(const struct tsens_device *tmdev)
> +{
> +	u32 reg_cntl;
> +	u32 mask;
> +
> +	mask = GENMASK(tmdev->num_sensors - 1, 0);
> +	mask <<= TSENS_SENSOR0_SHIFT;
> +	mask |= TSENS_EN;
> +
> +	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg_cntl);
> +	reg_cntl &= ~mask;
> +
> +	reg_cntl &= ~tmdev->slp_clk_enable;
> +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
> +}
> +
> +static void tsens_hw_init(struct tsens_device *tmdev)
> +{
> +	u32 reg_cntl, reg_thr;
> +
> +	reg_cntl = TSENS_SW_RST;
> +	regmap_update_bits(tmdev->map, TSENS_CNTL_ADDR, TSENS_SW_RST, reg_cntl);
> +
> +	if (tmdev->num_sensors > 1) {
> +		reg_cntl |= TSENS_8960_SLP_CLK_ENA | TSENS_8960_MEASURE_PERIOD;
> +		reg_cntl &= ~TSENS_SW_RST;
> +		regmap_update_bits(tmdev->map, TSENS_8960_CONFIG_ADDR,
> +				   TSENS_8960_CONFIG_MASK, TSENS_8960_CONFIG);
> +		tmdev->slp_clk_enable = TSENS_8960_SLP_CLK_ENA;
> +
> +	} else {
> +		reg_cntl |= TSENS_8660_SLP_CLK_ENA | TSENS_8660_MEASURE_PERIOD;
> +		reg_cntl &= ~TSENS_8660_CONFIG_MASK;
> +		reg_cntl |= TSENS_8660_CONFIG << TSENS_8660_CONFIG_SHIFT;
> +		tmdev->slp_clk_enable = TSENS_8660_SLP_CLK_ENA;
> +	}
> +
> +	reg_cntl |= GENMASK(tmdev->num_sensors - 1, 0) << TSENS_SENSOR0_SHIFT;
> +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
> +
> +	regmap_field_update_bits(tmdev->status_field,
> +			TSENS_LOWER_STATUS_CLR | TSENS_UPPER_STATUS_CLR |
> +			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK,
> +			TSENS_LOWER_STATUS_CLR | TSENS_UPPER_STATUS_CLR |
> +			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK);
> +
> +	reg_cntl |= TSENS_EN;
> +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
> +
> +	reg_thr = (TSENS_LOWER_LIMIT_TH << TSENS_THRESHOLD_LOWER_LIMIT_SHIFT) |
> +		(TSENS_UPPER_LIMIT_TH << TSENS_THRESHOLD_UPPER_LIMIT_SHIFT) |
> +		(TSENS_MIN_LIMIT_TH << TSENS_THRESHOLD_MIN_LIMIT_SHIFT) |
> +		(TSENS_MAX_LIMIT_TH << TSENS_THRESHOLD_MAX_LIMIT_SHIFT);
> +	regmap_write(tmdev->map, TSENS_THRESHOLD_ADDR, reg_thr);
> +}
> +
> +static int
> +tsens_calib_sensors(struct tsens_device *tmdev)
> +{
> +	int i;
> +	u8 *byte_data;
> +	u32 num_read;
> +	struct tsens_sensor *s = tmdev->sensor;
> +
> +	byte_data = devm_qfprom_get_data_byname(tmdev->dev, "calib", &num_read);
> +
> +	if (IS_ERR(byte_data) || !byte_data[0]
> +		|| num_read != tmdev->num_sensors)
> +		byte_data = devm_qfprom_get_data_byname(tmdev->dev,
> +			"backup_calib", &num_read);
> +
> +	if (IS_ERR(byte_data) || !byte_data[0]
> +		|| num_read != tmdev->num_sensors)
> +		return -EINVAL;
> +
> +	for (i = 0; i < num_read; i++, s++)
> +		s->offset = TSENS_CAL_MDEGC - s->slope * byte_data[i];
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops tsens_thermal_of_ops = {
> +	.get_temp = tsens_tz_get_temp,
> +};
> +
> +static int tsens_register(struct tsens_device *tmdev, int i)
> +{
> +	u32 addr = TSENS_S0_STATUS_ADDR;
> +	struct tsens_sensor *s = &tmdev->sensor[i];
> +
> +	/*
> +	* The status registers for each sensor are discontiguous
> +	* because some SoCs have 5 sensors while others have more
> +	* but the control registers stay in the same place, i.e.
> +	* directly after the first 5 status registers.
> +	*/
> +	if (i >= 5)
> +		addr += TSENS_SENSORABOVEFIVE_OFFSET;
> +
> +	addr += i * 4;
> +
> +	s->mode = THERMAL_DEVICE_ENABLED;
> +	s->sensor_num = i;
> +	s->status = addr;
> +	s->tmdev = tmdev;
> +	s->tz_dev = thermal_zone_of_sensor_register(tmdev->dev, i, s,
> +					&tsens_thermal_of_ops);
> +
> +	if (IS_ERR(s->tz_dev))
> +		return -ENODEV;
> +
> +	return 0;
> +}
> +
> +static int tsens_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	int ret, i, num;
> +	struct tsens_sensor *s;
> +	struct tsens_device *tmdev;
> +	struct regmap *map;
> +	struct reg_field *field;
> +	static struct reg_field status_0 = {
> +		.reg = TSENS_8064_STATUS_CNTL,
> +		.lsb = 0,
> +		.msb = 3,
> +	};
> +	static struct reg_field status_8 = {
> +		.reg = TSENS_CNTL_ADDR,
> +		.lsb = 8,
> +		.msb = 11,
> +	};
> +
> +	num = of_property_count_u32_elems(np, "qcom,tsens-slopes");
> +	if (num <= 0) {
> +		dev_err(&pdev->dev, "invalid tsens slopes\n");
> +		return -EINVAL;
> +	}
> +
> +	tmdev = devm_kzalloc(&pdev->dev, sizeof(*tmdev) +
> +			     num * sizeof(struct tsens_sensor), GFP_KERNEL);
> +	if (tmdev == NULL)
> +		return -ENOMEM;
> +
> +	tmdev->dev = &pdev->dev;
> +	tmdev->num_sensors = num;
> +
> +	for (i = 0, s = tmdev->sensor; i < num; i++, s++)
> +		of_property_read_u32_index(np, "qcom,tsens-slopes", i,
> +					   &s->slope);
> +
> +	ret = tsens_calib_sensors(tmdev);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "tsense calibration failed\n");
> +		return ret;
> +	}
> +
> +	tmdev->map = map = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!map)
> +		return -ENODEV;
> +
> +	/* Status bits move when the sensor bits next to them overlap */
> +	if (num > 5)
> +		field = &status_0;
> +	else
> +		field = &status_8;
> +
> +	tmdev->status_field = devm_regmap_field_alloc(&pdev->dev, map, *field);
> +	if (IS_ERR(tmdev->status_field)) {
> +		dev_err(&pdev->dev, "regmap alloc failed\n");
> +		return PTR_ERR(tmdev->status_field);
> +	}
> +
> +	tsens_hw_init(tmdev);
> +
> +	/*
> +	* Register sensor 0 separately. This sensor is always
> +	* expected to be present and if this fails, thermal
> +	* sensor probe would fail.
> +	* Other sensors are optional and if registration fails
> +	* disable the sensor and continue
> +	*/
> +	ret = tsens_register(tmdev, 0);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Registering failed for primary sensor");
> +		ret = -ENODEV;
> +		goto fail;
> +	} else {
> +		tsens_tz_set_mode(&tmdev->sensor[0], THERMAL_DEVICE_ENABLED);
> +	}
> +
> +	for (i = 1;  i < tmdev->num_sensors; i++) {
> +		ret = tsens_register(tmdev, i);
> +
> +		if (ret < 0) {
> +			dev_err(&pdev->dev,
> +				"Registering sensor(%i) failed - disabled", i);
> +			tsens_tz_set_mode(&tmdev->sensor[i],
> +				THERMAL_DEVICE_DISABLED);
> +		} else {
> +			tsens_tz_set_mode(&tmdev->sensor[i],
> +				THERMAL_DEVICE_ENABLED);
> +		}
> +	}
> +
> +	platform_set_drvdata(pdev, tmdev);
> +
> +	return 0;
> +fail:
> +	dev_err(&pdev->dev, "Tsens driver init failed\n");
> +	tsens_disable_mode(tmdev);
> +	return ret;
> +}
> +
> +static int tsens_remove(struct platform_device *pdev)
> +{
> +	int i;
> +	struct tsens_sensor *s;
> +	struct tsens_device *tmdev = platform_get_drvdata(pdev);
> +
> +	tsens_disable_mode(tmdev);
> +	for (i = 0, s = tmdev->sensor; i < tmdev->num_sensors; i++, s++)
> +		thermal_zone_device_unregister(s->tz_dev);
> +
> +	return 0;
> +}
> +
> +static struct of_device_id tsens_match_table[] = {
> +	{.compatible = "qcom,qcom-tsens"},
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(of, tsens_match_table);
> +
> +static struct platform_driver tsens_driver = {
> +	.probe = tsens_probe,
> +	.remove = tsens_remove,
> +	.driver = {
> +		.of_match_table = tsens_match_table,
> +		.name = "qcom-tsens",
> +		.pm	= TSENS_PM_OPS,
> +	},
> +};
> +module_platform_driver(tsens_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("QCOM Temperature Sensor driver");
> +MODULE_ALIAS("platform:qcom-tsens");
> -- 
> Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
>
Narendran Rajan Feb. 26, 2015, 5 a.m. UTC | #2
> -----Original Message-----
> From: linux-arm-msm-owner@vger.kernel.org [mailto:linux-arm-msm-
> owner@vger.kernel.org] On Behalf Of Eduardo Valentin
> Sent: Wednesday, February 25, 2015 11:44 AM
> To: Narendran Rajan
> Cc: Zhang Rui; Linux ARM MSM; Linux PM; Siddartha Mohanadoss; Stephen
> Boyd
> Subject: Re: [v3 1/2] thermal: Add qcom tsens thermal sensor driver
> 
> On Mon, Feb 23, 2015 at 10:47:21PM -0800, Narendran Rajan wrote:
> > TSENS supports reading temperature from multiple thermal sensors
> > present in QCOM SOCs.
> > TSENS HW is enabled only when the main sensor is requested.
> > TSENS block is disabled if the main senors is disabled irrespective of
> > any other sensors that are being enabled
> >
> > The driver needs calibration data which is read from qfprom.
> > Calibration data location is configured through dt files.
> >
> > Based on code by Siddartha Mohanadoss and Stephen Boyd.
> >
> > Cc: Siddartha Mohanadoss <smohanad@codeaurora.org>
> > Cc: Stephen Boyd <sboyd@codeaurora.org>
> > Signed-off-by: Narendran Rajan <nrajan@codeaurora.org>
> > ---
> >  .../devicetree/bindings/thermal/qcom-thermal.txt   |  59 +++
> >  drivers/thermal/Kconfig                            |  14 +
> >  drivers/thermal/Makefile                           |   1 +
> >  drivers/thermal/qcom-tsens.c                       | 493
+++++++++++++++++++++
> >  4 files changed, 567 insertions(+)
> >  create mode 100644
> > Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> >  create mode 100644 drivers/thermal/qcom-tsens.c
> >
> > diff --git
> > a/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> > b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> > new file mode 100644
> > index 0000000..d513043
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
> > @@ -0,0 +1,59 @@
> > +* QCOM SoC Temperature Sensor (TSENS)
> 
> Can you please add a brief description of this device and maybe a
> pointer/reference to its documentation?
> 
> 
> What are the current QCOM SoC supported? Or in which SoCs should we
> expect to see TSENS in?
> 

I added it elsewhere, but missed adding here. Will add. Thx

> > +
> > +Required properties:
> > +- compatible : "qcom,qcom-tsens"
> > +- qcom,tsens-slopes : Must contain slope value for each of the sensors
> controlled
> > +			by this device
> > +- qcom,qfprom : An array of triplets containing tsens calibration data.
> > +		The first element in the triplet is a phandle
> > +                to qfprom compatible node, second element is an offset
to
> calibration
> > +                data within this node, third element indicates size of
calibration
> > +                data. In general, there would be two elements in this
array - the
> > +                first containing information on primary calibration
data
> > +                and second containing information on backup
> > +calibration data
> > +- qcom,qfprom-names : Names for each calibration data
> > +- #thermal-sensor-cells : Should be 1. See ./thermal.txt for a
description.
> > +
> > +Example:
> > +
> > +tsens: tsens-msm8960 {
> > +		compatible = "qcom,qcom-tsens";
> > +		qcom,tsens-slopes = <1176 1176 1154 1176 1111
> > +				1132 1132 1199 1132 1199
> > +				1132>;
> 
> Please use the thermal zone coefficients property here. Describing slopes
is
> possible with current thermal.txt descriptors.
> 

When I read the purpose of coefficients in the documentation, it wasn't
clear
what the purpose was. It talks about describing the relationship between
various
sensors and no references in the code too.. Could you please confirm if this
could be 
used for describing the HW specific parameter (which is an absolute value
for each tsens sensor)

> 
> 
> > +		qcom,qfprom = <&imem 0x400 11>, <&imem 0x410 11>;
> > +		qcom,qfprom-names = "calib", "backup_calib";
> > +		#thermal-sensor-cells = <1>;
> > +	};
> > +
> > +Example: referring to thermal sensors:
> > +thermal-zones {
> > +	cpu_thermal: cpu_thermal {
> > +		polling-delay-passive = <1000>; /* milliseconds */
> > +		polling-delay = <5000>; /* milliseconds */
> > +
> > +		/* sensor ID */
> > +		thermal-sensors = <&tsens 1>;
> > +
> > +		trips {
> > +			cpu_alert0: cpu_alert {
> > +				temperature = <80000>; /* millicelsius */
> > +				hysteresis = <2000>; /* millicelsius */
> > +				type = "passive";
> > +			};
> > +			cpu_crit: cpu_crit {
> > +				temperature = <120000>; /* millicelsius */
> > +				hysteresis = <2000>; /* millicelsius */
> > +				type = "critical";
> > +			};
> > +		};
> > +
> > +		cooling-maps {
> > +			map0 {
> > +				trip = <&cpu_alert0>;
> > +				cooling-device =
> > +					<&cpu0 THERMAL_NO_LIMIT
> THERMAL_NO_LIMIT>;
> > +			};
> > +		};
> > +	};
> > +};
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index
> > af40db0..a57f1164 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -285,6 +285,20 @@ config ACPI_THERMAL_REL
> >  	tristate
> >  	depends on ACPI
> >
> > +config THERMAL_QCOM_TSENS
> > +	tristate "Qualcomm Tsens Temperature driver"
> > +	depends on THERMAL
> > +	depends on ARCH_QCOM
> > +	help
> > +	  QCOM tsens thermal driver provides support for Temperature
> sensor
> > +	  (TSENS) found on QCOM SoCs. It supports four configurable trip
> points
> > +	  and controls multiple sensors on the SOC. The four trip points are
> > +	  common across all sensors present in the SoC. The number of
> sensors
> > +	  present varies from chip to chip and are set through device tree
> entry.
> > +	  The driver presents as a standard thermal zone device with
> configurable
> > +	  trip points and cooling device mapping through standard thermal
> zone
> > +	  device tree.
> 
> Should we assume this driver supports all QCOM SoCs?
> 
No, only the A family chipsets (msm8660, msm8960, ipq6064). The B family 
chipset register layouts and programming model is slightly different.
Abstracting 
this out through a dtsi looked overkill and probably 
cleaner to write a separate driver for B family chips.

Let me check if there is a consensus around this and will update the
description
Accordingly.

> > +
> >  menu "Texas Instruments thermal drivers"
> >  source "drivers/thermal/ti-soc-thermal/Kconfig"
> >  endmenu
> > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index
> > fa0dc48..3fdf6b9 100644
> > --- a/drivers/thermal/Makefile
> > +++ b/drivers/thermal/Makefile
> > @@ -39,3 +39,4 @@ obj-$(CONFIG_TI_SOC_THERMAL)	+= ti-soc-
> thermal/
> >  obj-$(CONFIG_INT340X_THERMAL)  += int340x_thermal/
> >  obj-$(CONFIG_ST_THERMAL)	+= st/
> >  obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
> > +obj-$(CONFIG_THERMAL_QCOMTSENS)	+= qcom-tsens.o
> > diff --git a/drivers/thermal/qcom-tsens.c
> > b/drivers/thermal/qcom-tsens.c new file mode 100644 index
> > 0000000..accc6a74
> > --- /dev/null
> > +++ b/drivers/thermal/qcom-tsens.c
> > @@ -0,0 +1,493 @@
> > +/* 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/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/thermal.h>
> > +#include <linux/delay.h>
> > +#include <linux/slab.h>
> > +#include <linux/err.h>
> > +#include <linux/pm.h>
> > +#include <linux/bitops.h>
> > +#include <linux/regmap.h>
> > +#include <linux/of.h>
> > +#include <linux/of_platform.h>
> > +#include <soc/qcom/qfprom.h>
> > +
> > +#define TSENS_CAL_MDEGC                         30000
> > +
> > +#define TSENS_8960_CONFIG_ADDR                  0x3640
> > +#define TSENS_8960_CONFIG                       0x9b
> > +#define TSENS_8960_CONFIG_MASK                  0xff
> > +
> > +#define TSENS_CNTL_ADDR                         0x3620
> > +#define TSENS_EN                                BIT(0)
> > +#define TSENS_SW_RST                            BIT(1)
> > +#define SENSOR0_EN                              BIT(3)
> > +#define TSENS_MIN_STATUS_MASK                   BIT(0)
> > +#define TSENS_LOWER_STATUS_CLR                  BIT(1)
> > +#define TSENS_UPPER_STATUS_CLR                  BIT(2)
> > +#define TSENS_MAX_STATUS_MASK                   BIT(3)
> > +#define TSENS_8960_MEASURE_PERIOD               BIT(18)
> > +#define TSENS_8660_MEASURE_PERIOD               BIT(16)
> > +#define TSENS_8960_SLP_CLK_ENA                  BIT(26)
> > +#define TSENS_8660_SLP_CLK_ENA                  BIT(24)
> > +#define TSENS_8064_STATUS_CNTL                  0x3660
> > +
> > +#define TSENS_THRESHOLD_ADDR                    0x3624
> > +#define TSENS_THRESHOLD_MAX_CODE                0xff
> > +#define TSENS_THRESHOLD_MIN_CODE                0
> > +#define TSENS_THRESHOLD_MAX_LIMIT_SHIFT         24
> > +#define TSENS_THRESHOLD_MIN_LIMIT_SHIFT         16
> > +#define TSENS_THRESHOLD_UPPER_LIMIT_SHIFT       8
> > +#define TSENS_THRESHOLD_LOWER_LIMIT_SHIFT       0
> > +
> > +/* Initial temperature threshold values */
> > +#define TSENS_LOWER_LIMIT_TH                    0x50
> > +#define TSENS_UPPER_LIMIT_TH                    0xdf
> > +#define TSENS_MIN_LIMIT_TH                      0x0
> > +#define TSENS_MAX_LIMIT_TH                      0xff
> > +
> > +#define TSENS_S0_STATUS_ADDR                    0x3628
> > +
> > +#define TSENS_INT_STATUS_ADDR                   0x363c
> > +#define TSENS_TRDY_MASK                         BIT(7)
> > +
> > +#define TSENS_SENSOR0_SHIFT                     3
> > +
> > +#define TSENS_8660_CONFIG                       1
> > +#define TSENS_8660_CONFIG_SHIFT                 28
> > +#define TSENS_8660_CONFIG_MASK                  (3 <<
> TSENS_8660_CONFIG_SHIFT)
> > +#define TSENS_SENSORABOVEFIVE_OFFSET            40
> > +
> > +struct tsens_device;
> > +
> > +struct tsens_sensor {
> > +	struct thermal_zone_device	*tz_dev;
> > +	enum thermal_device_mode	mode;
> > +	unsigned int			sensor_num;
> > +	int				offset;
> > +	int				slope;
> > +	struct tsens_device		*tmdev;
> > +	u32                             status;
> > +};
> > +
> > +struct tsens_device {
> > +	struct device		*dev;
> > +	bool			prev_reading_avail;
> > +	unsigned int		num_sensors;
> > +	int			pm_tsens_thr_data;
> > +	int			pm_tsens_cntl;
> > +	u32			slp_clk_enable;
> > +	struct regmap		*map;
> > +	struct regmap_field	*status_field;
> > +	struct tsens_sensor	sensor[0];
> > +};
> > +
> > +/* Temperature on y axis and ADC-code on x-axis */ static int
> > +tsens_tz_code_to_mdegC(u32 adc_code, const struct tsens_sensor *s) {
> > +	return s->slope * adc_code + s->offset; }
> > +
> > +static int tsens_tz_get_temp(void *_sensor,
> > +			     long *temp)
> > +{
> > +	const struct tsens_sensor *tm_sensor = _sensor;
> > +	struct tsens_device *tmdev = tm_sensor->tmdev;
> > +	u32 code, trdy;
> > +
> > +	if (tm_sensor->mode != THERMAL_DEVICE_ENABLED)
> > +		return -EINVAL;
> > +
> > +	if (!tmdev->prev_reading_avail) {
> > +		while (!regmap_read(tmdev->map,
> TSENS_INT_STATUS_ADDR, &trdy) &&
> > +		       !(trdy & TSENS_TRDY_MASK))
> > +			usleep_range(1000, 1100);
> > +		tmdev->prev_reading_avail = true;
> > +	}
> > +
> > +	regmap_read(tmdev->map, tm_sensor->status, &code);
> > +	*temp = tsens_tz_code_to_mdegC(code, tm_sensor);
> > +
> > +	tmdev->prev_reading_avail = false;
> > +
> > +	dev_dbg(tmdev->dev, "Sensor %d temp is: %ld",
> > +		tm_sensor->sensor_num, *temp);
> > +	return 0;
> > +}
> > +
> > +/*
> > + * If the main sensor is disabled, rest of the sensors are disabled
> > + * along with the clock.
> > + * If the main sensor is disabled and a sub-sensor is enabled
> > + * return with an error.
> > + */
> > +static int tsens_tz_set_mode(struct tsens_sensor *tm_sensor,
> > +			      enum thermal_device_mode mode) {
> > +	struct tsens_device *tmdev = tm_sensor->tmdev;
> > +	unsigned int i, n = tmdev->num_sensors;
> > +	u32 reg, mask;
> > +
> > +	if (mode == tm_sensor->mode)
> > +		return 0;
> > +
> > +	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg);
> > +
> > +	mask = BIT(tm_sensor->sensor_num + TSENS_SENSOR0_SHIFT);
> > +	if (mode == THERMAL_DEVICE_ENABLED) {
> > +		if (!(reg & SENSOR0_EN) && mask != SENSOR0_EN) {
> > +			dev_warn(tmdev->dev, "Main sensor not
> enabled\n");
> > +			return -EINVAL;
> > +		}
> > +
> > +		regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg |
> TSENS_SW_RST);
> > +		reg |= mask | tmdev->slp_clk_enable | TSENS_EN;
> > +
> > +		tmdev->prev_reading_avail = false;
> > +	} else {
> > +		reg &= ~mask;
> > +		if (!(reg & SENSOR0_EN)) {
> > +			dev_warn(tmdev->dev, "Main sensor not enabled.
> Disabling
> > +subsensors\n");
> > +
> > +			reg &= ~GENMASK(n + TSENS_SENSOR0_SHIFT - 1,
> > +					TSENS_SENSOR0_SHIFT);
> > +			reg &= ~TSENS_EN;
> > +
> > +			reg &= ~tmdev->slp_clk_enable;
> > +
> > +			/* Disable all sub-sensors */
> > +			for (i = 1; i < n; i++)
> > +				tmdev->sensor[i].mode = mode;
> > +		}
> > +	}
> > +
> > +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg);
> > +	tm_sensor->mode = mode;
> > +
> > +	return 0;
> > +}
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static int tsens_suspend(struct device *dev) {
> > +	int i;
> > +	unsigned int mask;
> > +	struct tsens_device *tmdev = dev_get_drvdata(dev);
> > +	struct regmap *map = tmdev->map;
> > +
> > +	regmap_read(map, TSENS_THRESHOLD_ADDR, &tmdev-
> >pm_tsens_thr_data);
> > +	regmap_read(map, TSENS_CNTL_ADDR, &tmdev->pm_tsens_cntl);
> > +
> > +	mask = tmdev->slp_clk_enable | TSENS_EN;
> > +	regmap_update_bits(map, TSENS_CNTL_ADDR, mask, 0);
> > +
> > +	tmdev->prev_reading_avail = false;
> > +	for (i = 0; i < tmdev->num_sensors; i++)
> > +		tmdev->sensor[i].mode = THERMAL_DEVICE_DISABLED;
> > +
> > +	return 0;
> > +}
> > +
> > +static int tsens_resume(struct device *dev) {
> > +	int i;
> > +	unsigned long reg_cntl;
> > +	struct tsens_device *tmdev = dev_get_drvdata(dev);
> > +	struct regmap *map = tmdev->map;
> > +
> > +	regmap_update_bits(map, TSENS_CNTL_ADDR, TSENS_SW_RST,
> TSENS_SW_RST);
> > +	regmap_field_update_bits(tmdev->status_field,
> > +			TSENS_MIN_STATUS_MASK |
> TSENS_MAX_STATUS_MASK,
> > +			TSENS_MIN_STATUS_MASK |
> TSENS_MAX_STATUS_MASK);
> > +
> > +	/*
> > +	* Separate CONFIG restore is needed only for 8960. For 8660
> > +	* config is part of CTRL Addr and its restored as such
> > +	*/
> > +	if (tmdev->num_sensors > 1)
> > +		regmap_update_bits(map, TSENS_8960_CONFIG_ADDR,
> > +				TSENS_8960_CONFIG_MASK,
> > +				TSENS_8960_CONFIG);
> > +
> > +	regmap_write(map, TSENS_THRESHOLD_ADDR, tmdev-
> >pm_tsens_thr_data);
> > +	regmap_write(map, TSENS_CNTL_ADDR, tmdev->pm_tsens_cntl);
> > +
> > +	reg_cntl = tmdev->pm_tsens_cntl;
> > +	reg_cntl >>= TSENS_SENSOR0_SHIFT;
> > +	for_each_set_bit(i, &reg_cntl, tmdev->num_sensors)
> > +		tmdev->sensor[i].mode = THERMAL_DEVICE_ENABLED;
> > +
> > +	return 0;
> > +}
> > +
> > +static SIMPLE_DEV_PM_OPS(tsens_pm_ops, tsens_suspend,
> tsens_resume);
> > +#define TSENS_PM_OPS	(&tsens_pm_ops)
> > +
> > +#else /* CONFIG_PM_SLEEP */
> > +
> > +#define TSENS_PM_OPS	NULL
> > +
> > +#endif /* CONFIG_PM_SLEEP */
> > +
> > +static void tsens_disable_mode(const struct tsens_device *tmdev) {
> > +	u32 reg_cntl;
> > +	u32 mask;
> > +
> > +	mask = GENMASK(tmdev->num_sensors - 1, 0);
> > +	mask <<= TSENS_SENSOR0_SHIFT;
> > +	mask |= TSENS_EN;
> > +
> > +	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg_cntl);
> > +	reg_cntl &= ~mask;
> > +
> > +	reg_cntl &= ~tmdev->slp_clk_enable;
> > +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl); }
> > +
> > +static void tsens_hw_init(struct tsens_device *tmdev) {
> > +	u32 reg_cntl, reg_thr;
> > +
> > +	reg_cntl = TSENS_SW_RST;
> > +	regmap_update_bits(tmdev->map, TSENS_CNTL_ADDR,
> TSENS_SW_RST,
> > +reg_cntl);
> > +
> > +	if (tmdev->num_sensors > 1) {
> > +		reg_cntl |= TSENS_8960_SLP_CLK_ENA |
> TSENS_8960_MEASURE_PERIOD;
> > +		reg_cntl &= ~TSENS_SW_RST;
> > +		regmap_update_bits(tmdev->map,
> TSENS_8960_CONFIG_ADDR,
> > +				   TSENS_8960_CONFIG_MASK,
> TSENS_8960_CONFIG);
> > +		tmdev->slp_clk_enable = TSENS_8960_SLP_CLK_ENA;
> > +
> > +	} else {
> > +		reg_cntl |= TSENS_8660_SLP_CLK_ENA |
> TSENS_8660_MEASURE_PERIOD;
> > +		reg_cntl &= ~TSENS_8660_CONFIG_MASK;
> > +		reg_cntl |= TSENS_8660_CONFIG <<
> TSENS_8660_CONFIG_SHIFT;
> > +		tmdev->slp_clk_enable = TSENS_8660_SLP_CLK_ENA;
> > +	}
> > +
> > +	reg_cntl |= GENMASK(tmdev->num_sensors - 1, 0) <<
> TSENS_SENSOR0_SHIFT;
> > +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
> > +
> > +	regmap_field_update_bits(tmdev->status_field,
> > +			TSENS_LOWER_STATUS_CLR |
> TSENS_UPPER_STATUS_CLR |
> > +			TSENS_MIN_STATUS_MASK |
> TSENS_MAX_STATUS_MASK,
> > +			TSENS_LOWER_STATUS_CLR |
> TSENS_UPPER_STATUS_CLR |
> > +			TSENS_MIN_STATUS_MASK |
> TSENS_MAX_STATUS_MASK);
> > +
> > +	reg_cntl |= TSENS_EN;
> > +	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
> > +
> > +	reg_thr = (TSENS_LOWER_LIMIT_TH <<
> TSENS_THRESHOLD_LOWER_LIMIT_SHIFT) |
> > +		(TSENS_UPPER_LIMIT_TH <<
> TSENS_THRESHOLD_UPPER_LIMIT_SHIFT) |
> > +		(TSENS_MIN_LIMIT_TH <<
> TSENS_THRESHOLD_MIN_LIMIT_SHIFT) |
> > +		(TSENS_MAX_LIMIT_TH <<
> TSENS_THRESHOLD_MAX_LIMIT_SHIFT);
> > +	regmap_write(tmdev->map, TSENS_THRESHOLD_ADDR, reg_thr); }
> > +
> > +static int
> > +tsens_calib_sensors(struct tsens_device *tmdev) {
> > +	int i;
> > +	u8 *byte_data;
> > +	u32 num_read;
> > +	struct tsens_sensor *s = tmdev->sensor;
> > +
> > +	byte_data = devm_qfprom_get_data_byname(tmdev->dev, "calib",
> > +&num_read);
> > +
> > +	if (IS_ERR(byte_data) || !byte_data[0]
> > +		|| num_read != tmdev->num_sensors)
> > +		byte_data = devm_qfprom_get_data_byname(tmdev->dev,
> > +			"backup_calib", &num_read);
> > +
> > +	if (IS_ERR(byte_data) || !byte_data[0]
> > +		|| num_read != tmdev->num_sensors)
> > +		return -EINVAL;
> > +
> > +	for (i = 0; i < num_read; i++, s++)
> > +		s->offset = TSENS_CAL_MDEGC - s->slope * byte_data[i];
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct thermal_zone_of_device_ops tsens_thermal_of_ops =
> {
> > +	.get_temp = tsens_tz_get_temp,
> > +};
> > +
> > +static int tsens_register(struct tsens_device *tmdev, int i) {
> > +	u32 addr = TSENS_S0_STATUS_ADDR;
> > +	struct tsens_sensor *s = &tmdev->sensor[i];
> > +
> > +	/*
> > +	* The status registers for each sensor are discontiguous
> > +	* because some SoCs have 5 sensors while others have more
> > +	* but the control registers stay in the same place, i.e.
> > +	* directly after the first 5 status registers.
> > +	*/
> > +	if (i >= 5)
> > +		addr += TSENS_SENSORABOVEFIVE_OFFSET;
> > +
> > +	addr += i * 4;
> > +
> > +	s->mode = THERMAL_DEVICE_ENABLED;
> > +	s->sensor_num = i;
> > +	s->status = addr;
> > +	s->tmdev = tmdev;
> > +	s->tz_dev = thermal_zone_of_sensor_register(tmdev->dev, i, s,
> > +					&tsens_thermal_of_ops);
> > +
> > +	if (IS_ERR(s->tz_dev))
> > +		return -ENODEV;
> > +
> > +	return 0;
> > +}
> > +
> > +static int tsens_probe(struct platform_device *pdev) {
> > +	struct device_node *np = pdev->dev.of_node;
> > +	int ret, i, num;
> > +	struct tsens_sensor *s;
> > +	struct tsens_device *tmdev;
> > +	struct regmap *map;
> > +	struct reg_field *field;
> > +	static struct reg_field status_0 = {
> > +		.reg = TSENS_8064_STATUS_CNTL,
> > +		.lsb = 0,
> > +		.msb = 3,
> > +	};
> > +	static struct reg_field status_8 = {
> > +		.reg = TSENS_CNTL_ADDR,
> > +		.lsb = 8,
> > +		.msb = 11,
> > +	};
> > +
> > +	num = of_property_count_u32_elems(np, "qcom,tsens-slopes");
> > +	if (num <= 0) {
> > +		dev_err(&pdev->dev, "invalid tsens slopes\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	tmdev = devm_kzalloc(&pdev->dev, sizeof(*tmdev) +
> > +			     num * sizeof(struct tsens_sensor), GFP_KERNEL);
> > +	if (tmdev == NULL)
> > +		return -ENOMEM;
> > +
> > +	tmdev->dev = &pdev->dev;
> > +	tmdev->num_sensors = num;
> > +
> > +	for (i = 0, s = tmdev->sensor; i < num; i++, s++)
> > +		of_property_read_u32_index(np, "qcom,tsens-slopes", i,
> > +					   &s->slope);
> > +
> > +	ret = tsens_calib_sensors(tmdev);
> > +	if (ret < 0) {
> > +		dev_err(&pdev->dev, "tsense calibration failed\n");
> > +		return ret;
> > +	}
> > +
> > +	tmdev->map = map = dev_get_regmap(pdev->dev.parent, NULL);
> > +	if (!map)
> > +		return -ENODEV;
> > +
> > +	/* Status bits move when the sensor bits next to them overlap */
> > +	if (num > 5)
> > +		field = &status_0;
> > +	else
> > +		field = &status_8;
> > +
> > +	tmdev->status_field = devm_regmap_field_alloc(&pdev->dev, map,
> *field);
> > +	if (IS_ERR(tmdev->status_field)) {
> > +		dev_err(&pdev->dev, "regmap alloc failed\n");
> > +		return PTR_ERR(tmdev->status_field);
> > +	}
> > +
> > +	tsens_hw_init(tmdev);
> > +
> > +	/*
> > +	* Register sensor 0 separately. This sensor is always
> > +	* expected to be present and if this fails, thermal
> > +	* sensor probe would fail.
> > +	* Other sensors are optional and if registration fails
> > +	* disable the sensor and continue
> > +	*/
> > +	ret = tsens_register(tmdev, 0);
> > +	if (ret < 0) {
> > +		dev_err(&pdev->dev, "Registering failed for primary
> sensor");
> > +		ret = -ENODEV;
> > +		goto fail;
> > +	} else {
> > +		tsens_tz_set_mode(&tmdev->sensor[0],
> THERMAL_DEVICE_ENABLED);
> > +	}
> > +
> > +	for (i = 1;  i < tmdev->num_sensors; i++) {
> > +		ret = tsens_register(tmdev, i);
> > +
> > +		if (ret < 0) {
> > +			dev_err(&pdev->dev,
> > +				"Registering sensor(%i) failed - disabled",
i);
> > +			tsens_tz_set_mode(&tmdev->sensor[i],
> > +				THERMAL_DEVICE_DISABLED);
> > +		} else {
> > +			tsens_tz_set_mode(&tmdev->sensor[i],
> > +				THERMAL_DEVICE_ENABLED);
> > +		}
> > +	}
> > +
> > +	platform_set_drvdata(pdev, tmdev);
> > +
> > +	return 0;
> > +fail:
> > +	dev_err(&pdev->dev, "Tsens driver init failed\n");
> > +	tsens_disable_mode(tmdev);
> > +	return ret;
> > +}
> > +
> > +static int tsens_remove(struct platform_device *pdev) {
> > +	int i;
> > +	struct tsens_sensor *s;
> > +	struct tsens_device *tmdev = platform_get_drvdata(pdev);
> > +
> > +	tsens_disable_mode(tmdev);
> > +	for (i = 0, s = tmdev->sensor; i < tmdev->num_sensors; i++, s++)
> > +		thermal_zone_device_unregister(s->tz_dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct of_device_id tsens_match_table[] = {
> > +	{.compatible = "qcom,qcom-tsens"},
> > +	{},
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, tsens_match_table);
> > +
> > +static struct platform_driver tsens_driver = {
> > +	.probe = tsens_probe,
> > +	.remove = tsens_remove,
> > +	.driver = {
> > +		.of_match_table = tsens_match_table,
> > +		.name = "qcom-tsens",
> > +		.pm	= TSENS_PM_OPS,
> > +	},
> > +};
> > +module_platform_driver(tsens_driver);
> > +
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_DESCRIPTION("QCOM Temperature Sensor driver");
> > +MODULE_ALIAS("platform:qcom-tsens");
> > --
> > Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc.
> > is a member of the Code Aurora Forum, a Linux Foundation Collaborative
> > Project
> >

Thx, Naren

Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, 
a Linux Foundation Collaborative Project

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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/thermal/qcom-thermal.txt b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
new file mode 100644
index 0000000..d513043
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/qcom-thermal.txt
@@ -0,0 +1,59 @@ 
+* QCOM SoC Temperature Sensor (TSENS)
+
+Required properties:
+- compatible : "qcom,qcom-tsens"
+- qcom,tsens-slopes : Must contain slope value for each of the sensors controlled
+			by this device
+- qcom,qfprom : An array of triplets containing tsens calibration data.
+		The first element in the triplet is a phandle
+                to qfprom compatible node, second element is an offset to calibration
+                data within this node, third element indicates size of calibration
+                data. In general, there would be two elements in this array - the
+                first containing information on primary calibration data
+                and second containing information on backup calibration data
+- qcom,qfprom-names : Names for each calibration data
+- #thermal-sensor-cells : Should be 1. See ./thermal.txt for a description.
+
+Example:
+
+tsens: tsens-msm8960 {
+		compatible = "qcom,qcom-tsens";
+		qcom,tsens-slopes = <1176 1176 1154 1176 1111
+				1132 1132 1199 1132 1199
+				1132>;
+		qcom,qfprom = <&imem 0x400 11>, <&imem 0x410 11>;
+		qcom,qfprom-names = "calib", "backup_calib";
+		#thermal-sensor-cells = <1>;
+	};
+
+Example: referring to thermal sensors:
+thermal-zones {
+	cpu_thermal: cpu_thermal {
+		polling-delay-passive = <1000>; /* milliseconds */
+		polling-delay = <5000>; /* milliseconds */
+
+		/* sensor ID */
+		thermal-sensors = <&tsens 1>;
+
+		trips {
+			cpu_alert0: cpu_alert {
+				temperature = <80000>; /* millicelsius */
+				hysteresis = <2000>; /* millicelsius */
+				type = "passive";
+			};
+			cpu_crit: cpu_crit {
+				temperature = <120000>; /* millicelsius */
+				hysteresis = <2000>; /* millicelsius */
+				type = "critical";
+			};
+		};
+
+		cooling-maps {
+			map0 {
+				trip = <&cpu_alert0>;
+				cooling-device =
+					<&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			};
+		};
+	};
+};
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index af40db0..a57f1164 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -285,6 +285,20 @@  config ACPI_THERMAL_REL
 	tristate
 	depends on ACPI
 
+config THERMAL_QCOM_TSENS
+	tristate "Qualcomm Tsens Temperature driver"
+	depends on THERMAL
+	depends on ARCH_QCOM
+	help
+	  QCOM tsens thermal driver provides support for Temperature sensor
+	  (TSENS) found on QCOM SoCs. It supports four configurable trip points
+	  and controls multiple sensors on the SOC. The four trip points are
+	  common across all sensors present in the SoC. The number of sensors
+	  present varies from chip to chip and are set through device tree entry.
+	  The driver presents as a standard thermal zone device with configurable
+	  trip points and cooling device mapping through standard thermal zone
+	  device tree.
+
 menu "Texas Instruments thermal drivers"
 source "drivers/thermal/ti-soc-thermal/Kconfig"
 endmenu
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index fa0dc48..3fdf6b9 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -39,3 +39,4 @@  obj-$(CONFIG_TI_SOC_THERMAL)	+= ti-soc-thermal/
 obj-$(CONFIG_INT340X_THERMAL)  += int340x_thermal/
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
+obj-$(CONFIG_THERMAL_QCOMTSENS)	+= qcom-tsens.o
diff --git a/drivers/thermal/qcom-tsens.c b/drivers/thermal/qcom-tsens.c
new file mode 100644
index 0000000..accc6a74
--- /dev/null
+++ b/drivers/thermal/qcom-tsens.c
@@ -0,0 +1,493 @@ 
+/* 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/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/pm.h>
+#include <linux/bitops.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <soc/qcom/qfprom.h>
+
+#define TSENS_CAL_MDEGC                         30000
+
+#define TSENS_8960_CONFIG_ADDR                  0x3640
+#define TSENS_8960_CONFIG                       0x9b
+#define TSENS_8960_CONFIG_MASK                  0xff
+
+#define TSENS_CNTL_ADDR                         0x3620
+#define TSENS_EN                                BIT(0)
+#define TSENS_SW_RST                            BIT(1)
+#define SENSOR0_EN                              BIT(3)
+#define TSENS_MIN_STATUS_MASK                   BIT(0)
+#define TSENS_LOWER_STATUS_CLR                  BIT(1)
+#define TSENS_UPPER_STATUS_CLR                  BIT(2)
+#define TSENS_MAX_STATUS_MASK                   BIT(3)
+#define TSENS_8960_MEASURE_PERIOD               BIT(18)
+#define TSENS_8660_MEASURE_PERIOD               BIT(16)
+#define TSENS_8960_SLP_CLK_ENA                  BIT(26)
+#define TSENS_8660_SLP_CLK_ENA                  BIT(24)
+#define TSENS_8064_STATUS_CNTL                  0x3660
+
+#define TSENS_THRESHOLD_ADDR                    0x3624
+#define TSENS_THRESHOLD_MAX_CODE                0xff
+#define TSENS_THRESHOLD_MIN_CODE                0
+#define TSENS_THRESHOLD_MAX_LIMIT_SHIFT         24
+#define TSENS_THRESHOLD_MIN_LIMIT_SHIFT         16
+#define TSENS_THRESHOLD_UPPER_LIMIT_SHIFT       8
+#define TSENS_THRESHOLD_LOWER_LIMIT_SHIFT       0
+
+/* Initial temperature threshold values */
+#define TSENS_LOWER_LIMIT_TH                    0x50
+#define TSENS_UPPER_LIMIT_TH                    0xdf
+#define TSENS_MIN_LIMIT_TH                      0x0
+#define TSENS_MAX_LIMIT_TH                      0xff
+
+#define TSENS_S0_STATUS_ADDR                    0x3628
+
+#define TSENS_INT_STATUS_ADDR                   0x363c
+#define TSENS_TRDY_MASK                         BIT(7)
+
+#define TSENS_SENSOR0_SHIFT                     3
+
+#define TSENS_8660_CONFIG                       1
+#define TSENS_8660_CONFIG_SHIFT                 28
+#define TSENS_8660_CONFIG_MASK                  (3 << TSENS_8660_CONFIG_SHIFT)
+#define TSENS_SENSORABOVEFIVE_OFFSET            40
+
+struct tsens_device;
+
+struct tsens_sensor {
+	struct thermal_zone_device	*tz_dev;
+	enum thermal_device_mode	mode;
+	unsigned int			sensor_num;
+	int				offset;
+	int				slope;
+	struct tsens_device		*tmdev;
+	u32                             status;
+};
+
+struct tsens_device {
+	struct device		*dev;
+	bool			prev_reading_avail;
+	unsigned int		num_sensors;
+	int			pm_tsens_thr_data;
+	int			pm_tsens_cntl;
+	u32			slp_clk_enable;
+	struct regmap		*map;
+	struct regmap_field	*status_field;
+	struct tsens_sensor	sensor[0];
+};
+
+/* Temperature on y axis and ADC-code on x-axis */
+static int
+tsens_tz_code_to_mdegC(u32 adc_code, const struct tsens_sensor *s)
+{
+	return s->slope * adc_code + s->offset;
+}
+
+static int tsens_tz_get_temp(void *_sensor,
+			     long *temp)
+{
+	const struct tsens_sensor *tm_sensor = _sensor;
+	struct tsens_device *tmdev = tm_sensor->tmdev;
+	u32 code, trdy;
+
+	if (tm_sensor->mode != THERMAL_DEVICE_ENABLED)
+		return -EINVAL;
+
+	if (!tmdev->prev_reading_avail) {
+		while (!regmap_read(tmdev->map, TSENS_INT_STATUS_ADDR, &trdy) &&
+		       !(trdy & TSENS_TRDY_MASK))
+			usleep_range(1000, 1100);
+		tmdev->prev_reading_avail = true;
+	}
+
+	regmap_read(tmdev->map, tm_sensor->status, &code);
+	*temp = tsens_tz_code_to_mdegC(code, tm_sensor);
+
+	tmdev->prev_reading_avail = false;
+
+	dev_dbg(tmdev->dev, "Sensor %d temp is: %ld",
+		tm_sensor->sensor_num, *temp);
+	return 0;
+}
+
+/*
+ * If the main sensor is disabled, rest of the sensors are disabled
+ * along with the clock.
+ * If the main sensor is disabled and a sub-sensor is enabled
+ * return with an error.
+ */
+static int tsens_tz_set_mode(struct tsens_sensor *tm_sensor,
+			      enum thermal_device_mode mode)
+{
+	struct tsens_device *tmdev = tm_sensor->tmdev;
+	unsigned int i, n = tmdev->num_sensors;
+	u32 reg, mask;
+
+	if (mode == tm_sensor->mode)
+		return 0;
+
+	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg);
+
+	mask = BIT(tm_sensor->sensor_num + TSENS_SENSOR0_SHIFT);
+	if (mode == THERMAL_DEVICE_ENABLED) {
+		if (!(reg & SENSOR0_EN) && mask != SENSOR0_EN) {
+			dev_warn(tmdev->dev, "Main sensor not enabled\n");
+			return -EINVAL;
+		}
+
+		regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg | TSENS_SW_RST);
+		reg |= mask | tmdev->slp_clk_enable | TSENS_EN;
+
+		tmdev->prev_reading_avail = false;
+	} else {
+		reg &= ~mask;
+		if (!(reg & SENSOR0_EN)) {
+			dev_warn(tmdev->dev, "Main sensor not enabled. Disabling subsensors\n");
+
+			reg &= ~GENMASK(n + TSENS_SENSOR0_SHIFT - 1,
+					TSENS_SENSOR0_SHIFT);
+			reg &= ~TSENS_EN;
+
+			reg &= ~tmdev->slp_clk_enable;
+
+			/* Disable all sub-sensors */
+			for (i = 1; i < n; i++)
+				tmdev->sensor[i].mode = mode;
+		}
+	}
+
+	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg);
+	tm_sensor->mode = mode;
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tsens_suspend(struct device *dev)
+{
+	int i;
+	unsigned int mask;
+	struct tsens_device *tmdev = dev_get_drvdata(dev);
+	struct regmap *map = tmdev->map;
+
+	regmap_read(map, TSENS_THRESHOLD_ADDR, &tmdev->pm_tsens_thr_data);
+	regmap_read(map, TSENS_CNTL_ADDR, &tmdev->pm_tsens_cntl);
+
+	mask = tmdev->slp_clk_enable | TSENS_EN;
+	regmap_update_bits(map, TSENS_CNTL_ADDR, mask, 0);
+
+	tmdev->prev_reading_avail = false;
+	for (i = 0; i < tmdev->num_sensors; i++)
+		tmdev->sensor[i].mode = THERMAL_DEVICE_DISABLED;
+
+	return 0;
+}
+
+static int tsens_resume(struct device *dev)
+{
+	int i;
+	unsigned long reg_cntl;
+	struct tsens_device *tmdev = dev_get_drvdata(dev);
+	struct regmap *map = tmdev->map;
+
+	regmap_update_bits(map, TSENS_CNTL_ADDR, TSENS_SW_RST, TSENS_SW_RST);
+	regmap_field_update_bits(tmdev->status_field,
+			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK,
+			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK);
+
+	/*
+	* Separate CONFIG restore is needed only for 8960. For 8660
+	* config is part of CTRL Addr and its restored as such
+	*/
+	if (tmdev->num_sensors > 1)
+		regmap_update_bits(map, TSENS_8960_CONFIG_ADDR,
+				TSENS_8960_CONFIG_MASK,
+				TSENS_8960_CONFIG);
+
+	regmap_write(map, TSENS_THRESHOLD_ADDR, tmdev->pm_tsens_thr_data);
+	regmap_write(map, TSENS_CNTL_ADDR, tmdev->pm_tsens_cntl);
+
+	reg_cntl = tmdev->pm_tsens_cntl;
+	reg_cntl >>= TSENS_SENSOR0_SHIFT;
+	for_each_set_bit(i, &reg_cntl, tmdev->num_sensors)
+		tmdev->sensor[i].mode = THERMAL_DEVICE_ENABLED;
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(tsens_pm_ops, tsens_suspend, tsens_resume);
+#define TSENS_PM_OPS	(&tsens_pm_ops)
+
+#else /* CONFIG_PM_SLEEP */
+
+#define TSENS_PM_OPS	NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+static void tsens_disable_mode(const struct tsens_device *tmdev)
+{
+	u32 reg_cntl;
+	u32 mask;
+
+	mask = GENMASK(tmdev->num_sensors - 1, 0);
+	mask <<= TSENS_SENSOR0_SHIFT;
+	mask |= TSENS_EN;
+
+	regmap_read(tmdev->map, TSENS_CNTL_ADDR, &reg_cntl);
+	reg_cntl &= ~mask;
+
+	reg_cntl &= ~tmdev->slp_clk_enable;
+	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
+}
+
+static void tsens_hw_init(struct tsens_device *tmdev)
+{
+	u32 reg_cntl, reg_thr;
+
+	reg_cntl = TSENS_SW_RST;
+	regmap_update_bits(tmdev->map, TSENS_CNTL_ADDR, TSENS_SW_RST, reg_cntl);
+
+	if (tmdev->num_sensors > 1) {
+		reg_cntl |= TSENS_8960_SLP_CLK_ENA | TSENS_8960_MEASURE_PERIOD;
+		reg_cntl &= ~TSENS_SW_RST;
+		regmap_update_bits(tmdev->map, TSENS_8960_CONFIG_ADDR,
+				   TSENS_8960_CONFIG_MASK, TSENS_8960_CONFIG);
+		tmdev->slp_clk_enable = TSENS_8960_SLP_CLK_ENA;
+
+	} else {
+		reg_cntl |= TSENS_8660_SLP_CLK_ENA | TSENS_8660_MEASURE_PERIOD;
+		reg_cntl &= ~TSENS_8660_CONFIG_MASK;
+		reg_cntl |= TSENS_8660_CONFIG << TSENS_8660_CONFIG_SHIFT;
+		tmdev->slp_clk_enable = TSENS_8660_SLP_CLK_ENA;
+	}
+
+	reg_cntl |= GENMASK(tmdev->num_sensors - 1, 0) << TSENS_SENSOR0_SHIFT;
+	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
+
+	regmap_field_update_bits(tmdev->status_field,
+			TSENS_LOWER_STATUS_CLR | TSENS_UPPER_STATUS_CLR |
+			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK,
+			TSENS_LOWER_STATUS_CLR | TSENS_UPPER_STATUS_CLR |
+			TSENS_MIN_STATUS_MASK | TSENS_MAX_STATUS_MASK);
+
+	reg_cntl |= TSENS_EN;
+	regmap_write(tmdev->map, TSENS_CNTL_ADDR, reg_cntl);
+
+	reg_thr = (TSENS_LOWER_LIMIT_TH << TSENS_THRESHOLD_LOWER_LIMIT_SHIFT) |
+		(TSENS_UPPER_LIMIT_TH << TSENS_THRESHOLD_UPPER_LIMIT_SHIFT) |
+		(TSENS_MIN_LIMIT_TH << TSENS_THRESHOLD_MIN_LIMIT_SHIFT) |
+		(TSENS_MAX_LIMIT_TH << TSENS_THRESHOLD_MAX_LIMIT_SHIFT);
+	regmap_write(tmdev->map, TSENS_THRESHOLD_ADDR, reg_thr);
+}
+
+static int
+tsens_calib_sensors(struct tsens_device *tmdev)
+{
+	int i;
+	u8 *byte_data;
+	u32 num_read;
+	struct tsens_sensor *s = tmdev->sensor;
+
+	byte_data = devm_qfprom_get_data_byname(tmdev->dev, "calib", &num_read);
+
+	if (IS_ERR(byte_data) || !byte_data[0]
+		|| num_read != tmdev->num_sensors)
+		byte_data = devm_qfprom_get_data_byname(tmdev->dev,
+			"backup_calib", &num_read);
+
+	if (IS_ERR(byte_data) || !byte_data[0]
+		|| num_read != tmdev->num_sensors)
+		return -EINVAL;
+
+	for (i = 0; i < num_read; i++, s++)
+		s->offset = TSENS_CAL_MDEGC - s->slope * byte_data[i];
+
+	return 0;
+}
+
+static const struct thermal_zone_of_device_ops tsens_thermal_of_ops = {
+	.get_temp = tsens_tz_get_temp,
+};
+
+static int tsens_register(struct tsens_device *tmdev, int i)
+{
+	u32 addr = TSENS_S0_STATUS_ADDR;
+	struct tsens_sensor *s = &tmdev->sensor[i];
+
+	/*
+	* The status registers for each sensor are discontiguous
+	* because some SoCs have 5 sensors while others have more
+	* but the control registers stay in the same place, i.e.
+	* directly after the first 5 status registers.
+	*/
+	if (i >= 5)
+		addr += TSENS_SENSORABOVEFIVE_OFFSET;
+
+	addr += i * 4;
+
+	s->mode = THERMAL_DEVICE_ENABLED;
+	s->sensor_num = i;
+	s->status = addr;
+	s->tmdev = tmdev;
+	s->tz_dev = thermal_zone_of_sensor_register(tmdev->dev, i, s,
+					&tsens_thermal_of_ops);
+
+	if (IS_ERR(s->tz_dev))
+		return -ENODEV;
+
+	return 0;
+}
+
+static int tsens_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	int ret, i, num;
+	struct tsens_sensor *s;
+	struct tsens_device *tmdev;
+	struct regmap *map;
+	struct reg_field *field;
+	static struct reg_field status_0 = {
+		.reg = TSENS_8064_STATUS_CNTL,
+		.lsb = 0,
+		.msb = 3,
+	};
+	static struct reg_field status_8 = {
+		.reg = TSENS_CNTL_ADDR,
+		.lsb = 8,
+		.msb = 11,
+	};
+
+	num = of_property_count_u32_elems(np, "qcom,tsens-slopes");
+	if (num <= 0) {
+		dev_err(&pdev->dev, "invalid tsens slopes\n");
+		return -EINVAL;
+	}
+
+	tmdev = devm_kzalloc(&pdev->dev, sizeof(*tmdev) +
+			     num * sizeof(struct tsens_sensor), GFP_KERNEL);
+	if (tmdev == NULL)
+		return -ENOMEM;
+
+	tmdev->dev = &pdev->dev;
+	tmdev->num_sensors = num;
+
+	for (i = 0, s = tmdev->sensor; i < num; i++, s++)
+		of_property_read_u32_index(np, "qcom,tsens-slopes", i,
+					   &s->slope);
+
+	ret = tsens_calib_sensors(tmdev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "tsense calibration failed\n");
+		return ret;
+	}
+
+	tmdev->map = map = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!map)
+		return -ENODEV;
+
+	/* Status bits move when the sensor bits next to them overlap */
+	if (num > 5)
+		field = &status_0;
+	else
+		field = &status_8;
+
+	tmdev->status_field = devm_regmap_field_alloc(&pdev->dev, map, *field);
+	if (IS_ERR(tmdev->status_field)) {
+		dev_err(&pdev->dev, "regmap alloc failed\n");
+		return PTR_ERR(tmdev->status_field);
+	}
+
+	tsens_hw_init(tmdev);
+
+	/*
+	* Register sensor 0 separately. This sensor is always
+	* expected to be present and if this fails, thermal
+	* sensor probe would fail.
+	* Other sensors are optional and if registration fails
+	* disable the sensor and continue
+	*/
+	ret = tsens_register(tmdev, 0);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Registering failed for primary sensor");
+		ret = -ENODEV;
+		goto fail;
+	} else {
+		tsens_tz_set_mode(&tmdev->sensor[0], THERMAL_DEVICE_ENABLED);
+	}
+
+	for (i = 1;  i < tmdev->num_sensors; i++) {
+		ret = tsens_register(tmdev, i);
+
+		if (ret < 0) {
+			dev_err(&pdev->dev,
+				"Registering sensor(%i) failed - disabled", i);
+			tsens_tz_set_mode(&tmdev->sensor[i],
+				THERMAL_DEVICE_DISABLED);
+		} else {
+			tsens_tz_set_mode(&tmdev->sensor[i],
+				THERMAL_DEVICE_ENABLED);
+		}
+	}
+
+	platform_set_drvdata(pdev, tmdev);
+
+	return 0;
+fail:
+	dev_err(&pdev->dev, "Tsens driver init failed\n");
+	tsens_disable_mode(tmdev);
+	return ret;
+}
+
+static int tsens_remove(struct platform_device *pdev)
+{
+	int i;
+	struct tsens_sensor *s;
+	struct tsens_device *tmdev = platform_get_drvdata(pdev);
+
+	tsens_disable_mode(tmdev);
+	for (i = 0, s = tmdev->sensor; i < tmdev->num_sensors; i++, s++)
+		thermal_zone_device_unregister(s->tz_dev);
+
+	return 0;
+}
+
+static struct of_device_id tsens_match_table[] = {
+	{.compatible = "qcom,qcom-tsens"},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, tsens_match_table);
+
+static struct platform_driver tsens_driver = {
+	.probe = tsens_probe,
+	.remove = tsens_remove,
+	.driver = {
+		.of_match_table = tsens_match_table,
+		.name = "qcom-tsens",
+		.pm	= TSENS_PM_OPS,
+	},
+};
+module_platform_driver(tsens_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("QCOM Temperature Sensor driver");
+MODULE_ALIAS("platform:qcom-tsens");