diff mbox

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

Message ID 20150226190755.GB4941@developer.amazonguestwifi.org (mailing list archive)
State New, archived
Headers show

Commit Message

Eduardo Valentin Feb. 26, 2015, 7:07 p.m. UTC 
Narendran,

On Wed, Feb 25, 2015 at 09:00:53PM -0800, Narendran Rajan wrote:
> 
> > -----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


OK.

<cut>

> > > +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)


Yes, that optional property is to be used to specify the adjustment required
on top of the temperature readings coming from sensors. Typically due to
sensor placement, or because you need to combine several sensor readings
to get the desired temperature extrapolation to your thermal zone. The
thermal framework currently supports only one sensor per thermal zone though.

For the first case, the same temperature sensor (HW) may be placed in
different locations, from platform to platform (or even board version to
board version). Therefore, the raw readings from the hardware may need
adjustment. This seams the case you want to solve by adding a new DT
entry, specific to QCOM.

I want to have your DT spread with specific entry, given that we have
one that is originally thought to solve the same problem. I agree with
you though, that the current kernel code does not implement this
property. But, now it seams to be a good timing to get minimal support
for it. I know it is not the common case, but thing of your DT binding
as a separated thing from the Linux kernel. In theory, DT bindings are
not specific to Linux. It turns out that Linux just happens to support
what is specified by DT.

That, said, the thermal DT already supports simple linear temperature
extrapolation. We just need to add the support to Linux of-thermal.
Let me know if something like the below will help you to remove your
specific DT entry. You will need to change your code to fetch
slope and offset from thermal zone params structure (struct
thermal_zone_params) of your thermal zones. Also, you will need to add
the coefficients (slope and offset) in each thermal zone entry of your
DT.

/** This code is compiled tested only */





> 
> > 
> > 
> > > +		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
>
diff mbox

Patch

diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
index 668fb1b..13ed2a5 100644
--- a/drivers/thermal/of-thermal.c
+++ b/drivers/thermal/of-thermal.c
@@ -58,6 +58,8 @@  struct __thermal_bind_params {
  * @mode: current thermal zone device mode (enabled/disabled)
  * @passive_delay: polling interval while passive cooling is activated
  * @polling_delay: zone polling interval
+ * @slope: slope of the temperature adjustment curve
+ * @offset: offset of the temperature adjustment curve
  * @ntrips: number of trip points
  * @trips: an array of trip points (0..ntrips - 1)
  * @num_tbps: number of thermal bind params
@@ -70,6 +72,8 @@  struct __thermal_zone {
 	enum thermal_device_mode mode;
 	int passive_delay;
 	int polling_delay;
+	int slope;
+	int offset;
 
 	/* trip data */
 	int ntrips;
@@ -715,7 +719,7 @@  static int thermal_of_populate_trip(struct device_node *np,
  * @np parameter and fills the read data into a __thermal_zone data structure
  * and return this pointer.
  *
- * TODO: Missing properties to parse: thermal-sensor-names and coefficients
+ * TODO: Missing properties to parse: thermal-sensor-names
  *
  * Return: On success returns a valid struct __thermal_zone,
  * otherwise, it returns a corresponding ERR_PTR(). Caller must
@@ -727,7 +731,7 @@  thermal_of_build_thermal_zone(struct device_node *np)
 	struct device_node *child = NULL, *gchild;
 	struct __thermal_zone *tz;
 	int ret, i;
-	u32 prop;
+	u32 prop, coef[2];
 
 	if (!np) {
 		pr_err("no thermal zone np\n");
@@ -752,6 +756,20 @@  thermal_of_build_thermal_zone(struct device_node *np)
 	}
 	tz->polling_delay = prop;
 
+	/*
+	 * REVIST: for now, the thermal framework supports only
+	 * one sensor per thermal zone. Thus, we are considering
+	 * only the first two values as slope and offset.
+	 */
+	ret = of_property_read_u32_array(np, "coefficients", coef, 2);
+	if (ret == 0) {
+		tz->slope = coef[0];
+		tz->offset = coef[1];
+	} else {
+		tz->slope = 1;
+		tz->offset = 0;
+	}
+
 	/* trips */
 	child = of_get_child_by_name(np, "trips");
 
@@ -891,6 +909,10 @@  int __init of_parse_thermal_zones(void)
 		/* No hwmon because there might be hwmon drivers registering */
 		tzp->no_hwmon = true;
 
+		/* these two are left for temperature drivers to use */
+		tzp->slope = tz->slope;
+		tzp->offset = tz->offset;
+
 		zone = thermal_zone_device_register(child->name, tz->ntrips,
 						    0, tz,
 						    ops, tzp,
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 5eac316..2261db6 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -253,6 +253,16 @@  struct thermal_zone_params {
 
 	int num_tbps;	/* Number of tbp entries */
 	struct thermal_bind_params *tbp;
+	/*
+	 * @slope:	slope of a linear temperature adjustment curve.
+	 * 		Used by thermal zone drivers.
+	 */
+	int slope;
+	/*
+	 * @offset:	offset of a linear temperature adjustment curve.
+	 * 		Used by thermal zone drivers (default 0).
+	 */
+	int offset;
 };
 
 struct thermal_genl_event {