Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / thermal / kirkwood_thermal.c

diff --git a/kernel/drivers/thermal/kirkwood_thermal.c b/kernel/drivers/thermal/kirkwood_thermal.c
new file mode 100644 (file)
index 0000000..11041fe
--- /dev/null
+++ b/kernel/drivers/thermal/kirkwood_thermal.c
@@ -0,0 +1,125 @@
+/*
+ * 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. According to Marvell internal
+        * documentation the formula for this is:
+        * Celsius = (322-reg)/1.3625
+        */
+       reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
+               KIRKWOOD_THERMAL_TEMP_MASK;
+       *temp = ((3220000000UL - (10000000UL * reg)) / 13625);
+
+       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;
+
+       priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       priv->sensor = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(priv->sensor))
+               return PTR_ERR(priv->sensor);
+
+       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);
+
+       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",
+               .of_match_table = 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");