Thermal: Dove: Add Themal sensor support for Dove.

The Marvell Dove SoC has a thermal sensor. Add a driver using the
thermal framework.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

3 files changed, 218 insertions, 0 deletions

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 5070fbee24ef..24d913aa1003 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -126,6 +126,14 @@ config EXYNOS_THERMAL_EMUL
           device directory to support emulation mode. With emulation mode sysfs
           node, you can manually input temperature to TMU for simulation purpose.
 
+config DOVE_THERMAL
+        tristate "Temperature sensor on Marvell Dove SoCs"
+        depends on ARCH_DOVE
+        depends on OF
+        help
+          Support for the Dove thermal sensor driver in the Linux thermal
+          framework.
+
 config DB8500_THERMAL
         bool "DB8500 thermal management"
         depends on ARCH_U8500
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index b32c35de67e7..f5c01cce7768 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
 obj-$(CONFIG_RCAR_THERMAL)      += rcar_thermal.o
 obj-$(CONFIG_KIRKWOOD_THERMAL)  += kirkwood_thermal.o
 obj-$(CONFIG_EXYNOS_THERMAL)    += exynos_thermal.o
+obj-$(CONFIG_DOVE_THERMAL)      += dove_thermal.o
 obj-$(CONFIG_DB8500_THERMAL)    += db8500_thermal.o
 obj-$(CONFIG_DB8500_CPUFREQ_COOLING)    += db8500_cpufreq_cooling.o
 obj-$(CONFIG_INTEL_POWERCLAMP)  += intel_powerclamp.o
diff --git a/drivers/thermal/dove_thermal.c b/drivers/thermal/dove_thermal.c
new file mode 100644
index 000000000000..7b0bfa0e7a9c
--- /dev/null
+++ b/drivers/thermal/dove_thermal.c
@@ -0,0 +1,209 @@
+/*
+ * Dove thermal sensor driver
+ *
+ * Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+
+#define DOVE_THERMAL_TEMP_OFFSET        1
+#define DOVE_THERMAL_TEMP_MASK          0x1FF
+
+/* Dove Thermal Manager Control and Status Register */
+#define PMU_TM_DISABLE_OFFS             0
+#define PMU_TM_DISABLE_MASK             (0x1 << PMU_TM_DISABLE_OFFS)
+
+/* Dove Theraml Diode Control 0 Register */
+#define PMU_TDC0_SW_RST_MASK            (0x1 << 1)
+#define PMU_TDC0_SEL_VCAL_OFFS          5
+#define PMU_TDC0_SEL_VCAL_MASK          (0x3 << PMU_TDC0_SEL_VCAL_OFFS)
+#define PMU_TDC0_REF_CAL_CNT_OFFS       11
+#define PMU_TDC0_REF_CAL_CNT_MASK       (0x1FF << PMU_TDC0_REF_CAL_CNT_OFFS)
+#define PMU_TDC0_AVG_NUM_OFFS           25
+#define PMU_TDC0_AVG_NUM_MASK           (0x7 << PMU_TDC0_AVG_NUM_OFFS)
+
+/* Dove Thermal Diode Control 1 Register */
+#define PMU_TEMP_DIOD_CTRL1_REG         0x04
+#define PMU_TDC1_TEMP_VALID_MASK        (0x1 << 10)
+
+/* Dove Thermal Sensor Dev Structure */
+struct dove_thermal_priv {
+        void __iomem *sensor;
+        void __iomem *control;
+};
+
+static int dove_init_sensor(const struct dove_thermal_priv *priv)
+{
+        u32 reg;
+        u32 i;
+
+        /* Configure the Diode Control Register #0 */
+        reg = readl_relaxed(priv->control);
+
+        /* Use average of 2 */
+        reg &= ~PMU_TDC0_AVG_NUM_MASK;
+        reg |= (0x1 << PMU_TDC0_AVG_NUM_OFFS);
+
+        /* Reference calibration value */
+        reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
+        reg |= (0x0F1 << PMU_TDC0_REF_CAL_CNT_OFFS);
+
+        /* Set the high level reference for calibration */
+        reg &= ~PMU_TDC0_SEL_VCAL_MASK;
+        reg |= (0x2 << PMU_TDC0_SEL_VCAL_OFFS);
+        writel(reg, priv->control);
+
+        /* Reset the sensor */
+        reg = readl_relaxed(priv->control);
+        writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);
+        writel(reg, priv->control);
+
+        /* Enable the sensor */
+        reg = readl_relaxed(priv->sensor);
+        reg &= ~PMU_TM_DISABLE_MASK;
+        writel(reg, priv->sensor);
+
+        /* Poll the sensor for the first reading */
+        for (i = 0; i < 1000000; i++) {
+                reg = readl_relaxed(priv->sensor);
+                if (reg & DOVE_THERMAL_TEMP_MASK)
+                        break;
+        }
+
+        if (i == 1000000)
+                return -EIO;
+
+        return 0;
+}
+
+static int dove_get_temp(struct thermal_zone_device *thermal,
+                          unsigned long *temp)
+{
+        unsigned long reg;
+        struct dove_thermal_priv *priv = thermal->devdata;
+
+        /* Valid check */
+        reg = readl_relaxed(priv->control + PMU_TEMP_DIOD_CTRL1_REG);
+        if ((reg & PMU_TDC1_TEMP_VALID_MASK) == 0x0) {
+                dev_err(&thermal->device,
+                        "Temperature sensor reading not valid\n");
+                return -EIO;
+        }
+
+        /*
+         * Calculate temperature. See Section 8.10.1 of 88AP510,
+         * Documentation/arm/Marvell/README
+         */
+        reg = readl_relaxed(priv->sensor);
+        reg = (reg >> DOVE_THERMAL_TEMP_OFFSET) & DOVE_THERMAL_TEMP_MASK;
+        *temp = ((2281638UL - (7298*reg)) / 10);
+
+        return 0;
+}
+
+static struct thermal_zone_device_ops ops = {
+        .get_temp = dove_get_temp,
+};
+
+static const struct of_device_id dove_thermal_id_table[] = {
+        { .compatible = "marvell,dove-thermal" },
+        {}
+};
+
+static int dove_thermal_probe(struct platform_device *pdev)
+{
+        struct thermal_zone_device *thermal = NULL;
+        struct dove_thermal_priv *priv;
+        struct resource *res;
+        int ret;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "Failed to get platform resource\n");
+                return -ENODEV;
+        }
+
+        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        priv->sensor = devm_request_and_ioremap(&pdev->dev, res);
+        if (!priv->sensor) {
+                dev_err(&pdev->dev, "Failed to request_ioremap memory\n");
+                return -EADDRNOTAVAIL;
+        }
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+        if (!res) {
+                dev_err(&pdev->dev, "Failed to get platform resource\n");
+                return -ENODEV;
+        }
+        priv->control = devm_request_and_ioremap(&pdev->dev, res);
+        if (!priv->control) {
+                dev_err(&pdev->dev, "Failed to request_ioremap memory\n");
+                return -EADDRNOTAVAIL;
+        }
+
+        ret = dove_init_sensor(priv);
+        if (ret) {
+                dev_err(&pdev->dev, "Failed to initialize sensor\n");
+                return ret;
+        }
+
+        thermal = thermal_zone_device_register("dove_thermal", 0, 0,
+                                               priv, &ops, NULL, 0, 0);
+        if (IS_ERR(thermal)) {
+                dev_err(&pdev->dev,
+                        "Failed to register thermal zone device\n");
+                return PTR_ERR(thermal);
+        }
+
+        platform_set_drvdata(pdev, thermal);
+
+        return 0;
+}
+
+static int dove_thermal_exit(struct platform_device *pdev)
+{
+        struct thermal_zone_device *dove_thermal =
+                platform_get_drvdata(pdev);
+
+        thermal_zone_device_unregister(dove_thermal);
+        platform_set_drvdata(pdev, NULL);
+
+        return 0;
+}
+
+MODULE_DEVICE_TABLE(of, dove_thermal_id_table);
+
+static struct platform_driver dove_thermal_driver = {
+        .probe = dove_thermal_probe,
+        .remove = dove_thermal_exit,
+        .driver = {
+                .name = "dove_thermal",
+                .owner = THIS_MODULE,
+                .of_match_table = of_match_ptr(dove_thermal_id_table),
+        },
+};
+
+module_platform_driver(dove_thermal_driver);
+
+MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
+MODULE_DESCRIPTION("Dove thermal driver");
+MODULE_LICENSE("GPL");