Merge branch 'for_3.12/imx' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal into imx

4 files changed, 426 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/thermal/imx-thermal.txt b/Documentation/devicetree/bindings/thermal/imx-thermal.txt
new file mode 100644
index 000000000000..541c25e49abf
--- /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 e988c81d763c..69eed55b88b0 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 67184a293e3f..dff19c610bb0 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 000000000000..d16c33c7f3f0
--- /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");