--- /dev/null
+From ca3de46b50809000b5ba708634e26ad979a4a63a Mon Sep 17 00:00:00 2001
+From: Shawn Guo <shawn.guo@linaro.org>
+Date: Mon, 24 Jun 2013 14:30:44 +0800
+Subject: [PATCH] thermal: add imx thermal driver support
+
+This is based on the initial imx thermal work done by
+Rob Lee <rob.lee@linaro.org> (Not sure if the email address is still
+valid). Since he is no longer interested in the work and I have
+rewritten a significant amount of the code, I just took the authorship
+over from him.
+
+It adds the imx thermal support using Temperature Monitor (TEMPMON)
+block found on some Freescale i.MX SoCs. The driver uses syscon regmap
+interface to access TEMPMON control registers and calibration data, and
+supports cpufreq as the cooling device.
+
+Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
+Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
+---
+ .../devicetree/bindings/thermal/imx-thermal.txt | 17 +
+ drivers/thermal/Kconfig | 11 +
+ drivers/thermal/Makefile | 1 +
+ drivers/thermal/imx_thermal.c | 397 +++++++++++++++++++++
+ 4 files changed, 426 insertions(+)
+ create mode 100644 Documentation/devicetree/bindings/thermal/imx-thermal.txt
+ create mode 100644 drivers/thermal/imx_thermal.c
+
+diff --git a/Documentation/devicetree/bindings/thermal/imx-thermal.txt b/Documentation/devicetree/bindings/thermal/imx-thermal.txt
+new file mode 100644
+index 0000000..541c25e
+--- /dev/null
++++ b/Documentation/devicetree/bindings/thermal/imx-thermal.txt
+@@ -0,0 +1,17 @@
++* Temperature Monitor (TEMPMON) on Freescale i.MX SoCs
++
++Required properties:
++- compatible : "fsl,imx6q-thermal"
++- fsl,tempmon : phandle pointer to system controller that contains TEMPMON
++ control registers, e.g. ANATOP on imx6q.
++- fsl,tempmon-data : phandle pointer to fuse controller that contains TEMPMON
++ calibration data, e.g. OCOTP on imx6q. The details about calibration data
++ can be found in SoC Reference Manual.
++
++Example:
++
++tempmon {
++ compatible = "fsl,imx6q-tempmon";
++ fsl,tempmon = <&anatop>;
++ fsl,tempmon-data = <&ocotp>;
++};
+diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
+index e988c81..69eed55 100644
+--- a/drivers/thermal/Kconfig
++++ b/drivers/thermal/Kconfig
+@@ -91,6 +91,17 @@ config THERMAL_EMULATION
+ because userland can easily disable the thermal policy by simply
+ flooding this sysfs node with low temperature values.
+
++config IMX_THERMAL
++ tristate "Temperature sensor driver for Freescale i.MX SoCs"
++ depends on CPU_THERMAL
++ depends on MFD_SYSCON
++ depends on OF
++ help
++ Support for Temperature Monitor (TEMPMON) found on Freescale i.MX SoCs.
++ It supports one critical trip point and one passive trip point. The
++ cpufreq is used as the cooling device to throttle CPUs when the
++ passive trip is crossed.
++
+ config SPEAR_THERMAL
+ bool "SPEAr thermal sensor driver"
+ depends on PLAT_SPEAR
+diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
+index 67184a2..dff19c6 100644
+--- a/drivers/thermal/Makefile
++++ b/drivers/thermal/Makefile
+@@ -21,6 +21,7 @@ obj-$(CONFIG_EXYNOS_THERMAL) += exynos_thermal.o
+ obj-$(CONFIG_DOVE_THERMAL) += dove_thermal.o
+ obj-$(CONFIG_DB8500_THERMAL) += db8500_thermal.o
+ obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o
++obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o
+ obj-$(CONFIG_DB8500_CPUFREQ_COOLING) += db8500_cpufreq_cooling.o
+ obj-$(CONFIG_INTEL_POWERCLAMP) += intel_powerclamp.o
+ obj-$(CONFIG_X86_PKG_TEMP_THERMAL) += x86_pkg_temp_thermal.o
+diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
+new file mode 100644
+index 0000000..d16c33c
+--- /dev/null
++++ b/drivers/thermal/imx_thermal.c
+@@ -0,0 +1,397 @@
++/*
++ * Copyright 2013 Freescale Semiconductor, Inc.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ */
++
++#include <linux/cpu_cooling.h>
++#include <linux/cpufreq.h>
++#include <linux/delay.h>
++#include <linux/device.h>
++#include <linux/init.h>
++#include <linux/io.h>
++#include <linux/kernel.h>
++#include <linux/mfd/syscon.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/platform_device.h>
++#include <linux/regmap.h>
++#include <linux/slab.h>
++#include <linux/thermal.h>
++#include <linux/types.h>
++
++#define REG_SET 0x4
++#define REG_CLR 0x8
++#define REG_TOG 0xc
++
++#define MISC0 0x0150
++#define MISC0_REFTOP_SELBIASOFF (1 << 3)
++
++#define TEMPSENSE0 0x0180
++#define TEMPSENSE0_TEMP_CNT_SHIFT 8
++#define TEMPSENSE0_TEMP_CNT_MASK (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
++#define TEMPSENSE0_FINISHED (1 << 2)
++#define TEMPSENSE0_MEASURE_TEMP (1 << 1)
++#define TEMPSENSE0_POWER_DOWN (1 << 0)
++
++#define TEMPSENSE1 0x0190
++#define TEMPSENSE1_MEASURE_FREQ 0xffff
++
++#define OCOTP_ANA1 0x04e0
++
++/* The driver supports 1 passive trip point and 1 critical trip point */
++enum imx_thermal_trip {
++ IMX_TRIP_PASSIVE,
++ IMX_TRIP_CRITICAL,
++ IMX_TRIP_NUM,
++};
++
++/*
++ * It defines the temperature in millicelsius for passive trip point
++ * that will trigger cooling action when crossed.
++ */
++#define IMX_TEMP_PASSIVE 85000
++
++/*
++ * The maximum die temperature on imx parts is 105C, let's give some cushion
++ * for noise and possible temperature rise between measurements.
++ */
++#define IMX_TEMP_CRITICAL 100000
++
++#define IMX_POLLING_DELAY 2000 /* millisecond */
++#define IMX_PASSIVE_DELAY 1000
++
++struct imx_thermal_data {
++ struct thermal_zone_device *tz;
++ struct thermal_cooling_device *cdev;
++ enum thermal_device_mode mode;
++ struct regmap *tempmon;
++ int c1, c2; /* See formula in imx_get_sensor_data() */
++};
++
++static int imx_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
++{
++ struct imx_thermal_data *data = tz->devdata;
++ struct regmap *map = data->tempmon;
++ static unsigned long last_temp;
++ unsigned int n_meas;
++ u32 val;
++
++ /*
++ * Every time we measure the temperature, we will power on the
++ * temperature sensor, enable measurements, take a reading,
++ * disable measurements, power off the temperature sensor.
++ */
++ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
++ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
++
++ /*
++ * According to the temp sensor designers, it may require up to ~17us
++ * to complete a measurement.
++ */
++ usleep_range(20, 50);
++
++ regmap_read(map, TEMPSENSE0, &val);
++ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
++ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
++
++ if ((val & TEMPSENSE0_FINISHED) == 0) {
++ dev_dbg(&tz->device, "temp measurement never finished\n");
++ return -EAGAIN;
++ }
++
++ n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
++
++ /* See imx_get_sensor_data() for formula derivation */
++ *temp = data->c2 + data->c1 * n_meas;
++
++ if (*temp != last_temp) {
++ dev_dbg(&tz->device, "millicelsius: %ld\n", *temp);
++ last_temp = *temp;
++ }
++
++ return 0;
++}
++
++static int imx_get_mode(struct thermal_zone_device *tz,
++ enum thermal_device_mode *mode)
++{
++ struct imx_thermal_data *data = tz->devdata;
++
++ *mode = data->mode;
++
++ return 0;
++}
++
++static int imx_set_mode(struct thermal_zone_device *tz,
++ enum thermal_device_mode mode)
++{
++ struct imx_thermal_data *data = tz->devdata;
++
++ if (mode == THERMAL_DEVICE_ENABLED) {
++ tz->polling_delay = IMX_POLLING_DELAY;
++ tz->passive_delay = IMX_PASSIVE_DELAY;
++ } else {
++ tz->polling_delay = 0;
++ tz->passive_delay = 0;
++ }
++
++ data->mode = mode;
++ thermal_zone_device_update(tz);
++
++ return 0;
++}
++
++static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
++ enum thermal_trip_type *type)
++{
++ *type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
++ THERMAL_TRIP_CRITICAL;
++ return 0;
++}
++
++static int imx_get_crit_temp(struct thermal_zone_device *tz,
++ unsigned long *temp)
++{
++ *temp = IMX_TEMP_CRITICAL;
++ return 0;
++}
++
++static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
++ unsigned long *temp)
++{
++ *temp = (trip == IMX_TRIP_PASSIVE) ? IMX_TEMP_PASSIVE :
++ IMX_TEMP_CRITICAL;
++ return 0;
++}
++
++static int imx_bind(struct thermal_zone_device *tz,
++ struct thermal_cooling_device *cdev)
++{
++ int ret;
++
++ ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
++ THERMAL_NO_LIMIT,
++ THERMAL_NO_LIMIT);
++ if (ret) {
++ dev_err(&tz->device,
++ "binding zone %s with cdev %s failed:%d\n",
++ tz->type, cdev->type, ret);
++ return ret;
++ }
++
++ return 0;
++}
++
++static int imx_unbind(struct thermal_zone_device *tz,
++ struct thermal_cooling_device *cdev)
++{
++ int ret;
++
++ ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
++ if (ret) {
++ dev_err(&tz->device,
++ "unbinding zone %s with cdev %s failed:%d\n",
++ tz->type, cdev->type, ret);
++ return ret;
++ }
++
++ return 0;
++}
++
++static const struct thermal_zone_device_ops imx_tz_ops = {
++ .bind = imx_bind,
++ .unbind = imx_unbind,
++ .get_temp = imx_get_temp,
++ .get_mode = imx_get_mode,
++ .set_mode = imx_set_mode,
++ .get_trip_type = imx_get_trip_type,
++ .get_trip_temp = imx_get_trip_temp,
++ .get_crit_temp = imx_get_crit_temp,
++};
++
++static int imx_get_sensor_data(struct platform_device *pdev)
++{
++ struct imx_thermal_data *data = platform_get_drvdata(pdev);
++ struct regmap *map;
++ int t1, t2, n1, n2;
++ int ret;
++ u32 val;
++
++ map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
++ "fsl,tempmon-data");
++ if (IS_ERR(map)) {
++ ret = PTR_ERR(map);
++ dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
++ return ret;
++ }
++
++ ret = regmap_read(map, OCOTP_ANA1, &val);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
++ return ret;
++ }
++
++ if (val == 0 || val == ~0) {
++ dev_err(&pdev->dev, "invalid sensor calibration data\n");
++ return -EINVAL;
++ }
++
++ /*
++ * Sensor data layout:
++ * [31:20] - sensor value @ 25C
++ * [19:8] - sensor value of hot
++ * [7:0] - hot temperature value
++ */
++ n1 = val >> 20;
++ n2 = (val & 0xfff00) >> 8;
++ t2 = val & 0xff;
++ t1 = 25; /* t1 always 25C */
++
++ /*
++ * Derived from linear interpolation,
++ * Tmeas = T2 + (Nmeas - N2) * (T1 - T2) / (N1 - N2)
++ * We want to reduce this down to the minimum computation necessary
++ * for each temperature read. Also, we want Tmeas in millicelsius
++ * and we don't want to lose precision from integer division. So...
++ * milli_Tmeas = 1000 * T2 + 1000 * (Nmeas - N2) * (T1 - T2) / (N1 - N2)
++ * Let constant c1 = 1000 * (T1 - T2) / (N1 - N2)
++ * milli_Tmeas = (1000 * T2) + c1 * (Nmeas - N2)
++ * milli_Tmeas = (1000 * T2) + (c1 * Nmeas) - (c1 * N2)
++ * Let constant c2 = (1000 * T2) - (c1 * N2)
++ * milli_Tmeas = c2 + (c1 * Nmeas)
++ */
++ data->c1 = 1000 * (t1 - t2) / (n1 - n2);
++ data->c2 = 1000 * t2 - data->c1 * n2;
++
++ return 0;
++}
++
++static int imx_thermal_probe(struct platform_device *pdev)
++{
++ struct imx_thermal_data *data;
++ struct cpumask clip_cpus;
++ struct regmap *map;
++ int ret;
++
++ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
++ if (!data)
++ return -ENOMEM;
++
++ map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
++ if (IS_ERR(map)) {
++ ret = PTR_ERR(map);
++ dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
++ return ret;
++ }
++ data->tempmon = map;
++
++ platform_set_drvdata(pdev, data);
++
++ ret = imx_get_sensor_data(pdev);
++ if (ret) {
++ dev_err(&pdev->dev, "failed to get sensor data\n");
++ return ret;
++ }
++
++ /* Make sure sensor is in known good state for measurements */
++ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
++ regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
++ regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
++ regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
++ regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
++
++ cpumask_set_cpu(0, &clip_cpus);
++ data->cdev = cpufreq_cooling_register(&clip_cpus);
++ if (IS_ERR(data->cdev)) {
++ ret = PTR_ERR(data->cdev);
++ dev_err(&pdev->dev,
++ "failed to register cpufreq cooling device: %d\n", ret);
++ return ret;
++ }
++
++ data->tz = thermal_zone_device_register("imx_thermal_zone",
++ IMX_TRIP_NUM, 0, data,
++ &imx_tz_ops, NULL,
++ IMX_PASSIVE_DELAY,
++ IMX_POLLING_DELAY);
++ if (IS_ERR(data->tz)) {
++ ret = PTR_ERR(data->tz);
++ dev_err(&pdev->dev,
++ "failed to register thermal zone device %d\n", ret);
++ cpufreq_cooling_unregister(data->cdev);
++ return ret;
++ }
++
++ data->mode = THERMAL_DEVICE_ENABLED;
++
++ return 0;
++}
++
++static int imx_thermal_remove(struct platform_device *pdev)
++{
++ struct imx_thermal_data *data = platform_get_drvdata(pdev);
++
++ thermal_zone_device_unregister(data->tz);
++ cpufreq_cooling_unregister(data->cdev);
++
++ return 0;
++}
++
++#ifdef CONFIG_PM_SLEEP
++static int imx_thermal_suspend(struct device *dev)
++{
++ struct imx_thermal_data *data = dev_get_drvdata(dev);
++ struct regmap *map = data->tempmon;
++ u32 val;
++
++ regmap_read(map, TEMPSENSE0, &val);
++ if ((val & TEMPSENSE0_POWER_DOWN) == 0) {
++ /*
++ * If a measurement is taking place, wait for a long enough
++ * time for it to finish, and then check again. If it still
++ * does not finish, something must go wrong.
++ */
++ udelay(50);
++ regmap_read(map, TEMPSENSE0, &val);
++ if ((val & TEMPSENSE0_POWER_DOWN) == 0)
++ return -ETIMEDOUT;
++ }
++
++ return 0;
++}
++
++static int imx_thermal_resume(struct device *dev)
++{
++ /* Nothing to do for now */
++ return 0;
++}
++#endif
++
++static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
++ imx_thermal_suspend, imx_thermal_resume);
++
++static const struct of_device_id of_imx_thermal_match[] = {
++ { .compatible = "fsl,imx6q-tempmon", },
++ { /* end */ }
++};
++
++static struct platform_driver imx_thermal = {
++ .driver = {
++ .name = "imx_thermal",
++ .owner = THIS_MODULE,
++ .pm = &imx_thermal_pm_ops,
++ .of_match_table = of_imx_thermal_match,
++ },
++ .probe = imx_thermal_probe,
++ .remove = imx_thermal_remove,
++};
++module_platform_driver(imx_thermal);
++
++MODULE_AUTHOR("Freescale Semiconductor, Inc.");
++MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
++MODULE_LICENSE("GPL v2");
++MODULE_ALIAS("platform:imx-thermal");
+--
+1.8.4
+
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