thermal: Add support for the thermal sensor on Kirkwood SoCs
This patch adds support for Kirkwood 88F6282 and 88F6283 thermal sensor.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
diff --git a/drivers/thermal/kirkwood_thermal.c b/drivers/thermal/kirkwood_thermal.c
new file mode 100644
index 0000000..65cb4f0
--- /dev/null
+++ b/drivers/thermal/kirkwood_thermal.c
@@ -0,0 +1,134 @@
+/*
+ * Kirkwood thermal sensor driver
+ *
+ * Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
+ *
+ * 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 KIRKWOOD_THERMAL_VALID_OFFSET 9
+#define KIRKWOOD_THERMAL_VALID_MASK 0x1
+#define KIRKWOOD_THERMAL_TEMP_OFFSET 10
+#define KIRKWOOD_THERMAL_TEMP_MASK 0x1FF
+
+/* Kirkwood Thermal Sensor Dev Structure */
+struct kirkwood_thermal_priv {
+ void __iomem *sensor;
+};
+
+static int kirkwood_get_temp(struct thermal_zone_device *thermal,
+ unsigned long *temp)
+{
+ unsigned long reg;
+ struct kirkwood_thermal_priv *priv = thermal->devdata;
+
+ reg = readl_relaxed(priv->sensor);
+
+ /* Valid check */
+ if (!(reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
+ KIRKWOOD_THERMAL_VALID_MASK) {
+ dev_err(&thermal->device,
+ "Temperature sensor reading not valid\n");
+ return -EIO;
+ }
+
+ /*
+ * Calculate temperature. See Section 8.10.1 of the 88AP510,
+ * datasheet, which has the same sensor.
+ * Documentation/arm/Marvell/README
+ */
+ reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
+ KIRKWOOD_THERMAL_TEMP_MASK;
+ *temp = ((2281638UL - (7298*reg)) / 10);
+
+ return 0;
+}
+
+static struct thermal_zone_device_ops ops = {
+ .get_temp = kirkwood_get_temp,
+};
+
+static const struct of_device_id kirkwood_thermal_id_table[] = {
+ { .compatible = "marvell,kirkwood-thermal" },
+ {}
+};
+
+static int kirkwood_thermal_probe(struct platform_device *pdev)
+{
+ struct thermal_zone_device *thermal = NULL;
+ struct kirkwood_thermal_priv *priv;
+ struct resource *res;
+
+ 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;
+ }
+
+ thermal = thermal_zone_device_register("kirkwood_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 kirkwood_thermal_exit(struct platform_device *pdev)
+{
+ struct thermal_zone_device *kirkwood_thermal =
+ platform_get_drvdata(pdev);
+
+ thermal_zone_device_unregister(kirkwood_thermal);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
+
+static struct platform_driver kirkwood_thermal_driver = {
+ .probe = kirkwood_thermal_probe,
+ .remove = kirkwood_thermal_exit,
+ .driver = {
+ .name = "kirkwood_thermal",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(kirkwood_thermal_id_table),
+ },
+};
+
+module_platform_driver(kirkwood_thermal_driver);
+
+MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
+MODULE_DESCRIPTION("kirkwood thermal driver");
+MODULE_LICENSE("GPL");