--- /dev/null
+/*
+ * SPEAr thermal driver.
+ *
+ * Copyright (C) 2011-2012 ST Microelectronics
+ * Author: Vincenzo Frascino <vincenzo.frascino@st.com>
+ *
+ * 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/clk.h>
+#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 MD_FACTOR 1000
+
+/* SPEAr Thermal Sensor Dev Structure */
+struct spear_thermal_dev {
+ /* pointer to base address of the thermal sensor */
+ void __iomem *thermal_base;
+ /* clk structure */
+ struct clk *clk;
+ /* pointer to thermal flags */
+ unsigned int flags;
+};
+
+static inline int thermal_get_temp(struct thermal_zone_device *thermal,
+ unsigned long *temp)
+{
+ struct spear_thermal_dev *stdev = thermal->devdata;
+
+ /*
+ * Data are ready to be read after 628 usec from POWERDOWN signal
+ * (PDN) = 1
+ */
+ *temp = (readl_relaxed(stdev->thermal_base) & 0x7F) * MD_FACTOR;
+ return 0;
+}
+
+static struct thermal_zone_device_ops ops = {
+ .get_temp = thermal_get_temp,
+};
+
+#ifdef CONFIG_PM
+static int spear_thermal_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+ unsigned int actual_mask = 0;
+
+ /* Disable SPEAr Thermal Sensor */
+ actual_mask = readl_relaxed(stdev->thermal_base);
+ writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
+
+ clk_disable(stdev->clk);
+ dev_info(dev, "Suspended.\n");
+
+ return 0;
+}
+
+static int spear_thermal_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+ unsigned int actual_mask = 0;
+ int ret = 0;
+
+ ret = clk_enable(stdev->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Can't enable clock\n");
+ return ret;
+ }
+
+ /* Enable SPEAr Thermal Sensor */
+ actual_mask = readl_relaxed(stdev->thermal_base);
+ writel_relaxed(actual_mask | stdev->flags, stdev->thermal_base);
+
+ dev_info(dev, "Resumed.\n");
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,
+ spear_thermal_resume);
+
+static int spear_thermal_probe(struct platform_device *pdev)
+{
+ struct thermal_zone_device *spear_thermal = NULL;
+ struct spear_thermal_dev *stdev;
+ struct device_node *np = pdev->dev.of_node;
+ struct resource *res;
+ int ret = 0, val;
+
+ if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {
+ dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");
+ return -EINVAL;
+ }
+
+ stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
+ if (!stdev)
+ return -ENOMEM;
+
+ /* Enable thermal sensor */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ stdev->thermal_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(stdev->thermal_base))
+ return PTR_ERR(stdev->thermal_base);
+
+ stdev->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(stdev->clk)) {
+ dev_err(&pdev->dev, "Can't get clock\n");
+ return PTR_ERR(stdev->clk);
+ }
+
+ ret = clk_enable(stdev->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Can't enable clock\n");
+ return ret;
+ }
+
+ stdev->flags = val;
+ writel_relaxed(stdev->flags, stdev->thermal_base);
+
+ spear_thermal = thermal_zone_device_register("spear_thermal", 0, 0,
+ stdev, &ops, NULL, 0, 0);
+ if (IS_ERR(spear_thermal)) {
+ dev_err(&pdev->dev, "thermal zone device is NULL\n");
+ ret = PTR_ERR(spear_thermal);
+ goto disable_clk;
+ }
+
+ platform_set_drvdata(pdev, spear_thermal);
+
+ dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%p.\n",
+ stdev->thermal_base);
+
+ return 0;
+
+disable_clk:
+ clk_disable(stdev->clk);
+
+ return ret;
+}
+
+static int spear_thermal_exit(struct platform_device *pdev)
+{
+ unsigned int actual_mask = 0;
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+
+ thermal_zone_device_unregister(spear_thermal);
+
+ /* Disable SPEAr Thermal Sensor */
+ actual_mask = readl_relaxed(stdev->thermal_base);
+ writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
+
+ clk_disable(stdev->clk);
+
+ return 0;
+}
+
+static const struct of_device_id spear_thermal_id_table[] = {
+ { .compatible = "st,thermal-spear1340" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, spear_thermal_id_table);
+
+static struct platform_driver spear_thermal_driver = {
+ .probe = spear_thermal_probe,
+ .remove = spear_thermal_exit,
+ .driver = {
+ .name = "spear_thermal",
+ .pm = &spear_thermal_pm_ops,
+ .of_match_table = spear_thermal_id_table,
+ },
+};
+
+module_platform_driver(spear_thermal_driver);
+
+MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>");
+MODULE_DESCRIPTION("SPEAr thermal driver");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff