--- /dev/null
+/*
+ * 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");
projects / linux-beck.git / commitdiff