clockevent: sun4i: Fix race condition in the probe code

[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / thermal / imx_thermal.c

diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index 1d6c801..45af765 100644 (file)
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -7,6 +7,7 @@
  *
  */
 
+#include <linux/clk.h>
 #include <linux/cpu_cooling.h>
 #include <linux/cpufreq.h>
 #include <linux/delay.h>
@@ -73,6 +74,7 @@ struct imx_thermal_data {
        unsigned long last_temp;
        bool irq_enabled;
        int irq;
+       struct clk *thermal_clk;
 };
 
 static void imx_set_alarm_temp(struct imx_thermal_data *data,
@@ -284,7 +286,7 @@ static int imx_unbind(struct thermal_zone_device *tz,
        return 0;
 }
 
-static const struct thermal_zone_device_ops imx_tz_ops = {
+static struct thermal_zone_device_ops imx_tz_ops = {
        .bind = imx_bind,
        .unbind = imx_unbind,
        .get_temp = imx_get_temp,
@@ -457,6 +459,22 @@ static int imx_thermal_probe(struct platform_device *pdev)
                return ret;
        }
 
+       data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
+       if (IS_ERR(data->thermal_clk)) {
+               dev_warn(&pdev->dev, "failed to get thermal clk!\n");
+       } else {
+               /*
+                * Thermal sensor needs clk on to get correct value, normally
+                * we should enable its clk before taking measurement and disable
+                * clk after measurement is done, but if alarm function is enabled,
+                * hardware will auto measure the temperature periodically, so we
+                * need to keep the clk always on for alarm function.
+                */
+               ret = clk_prepare_enable(data->thermal_clk);
+               if (ret)
+                       dev_warn(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
+       }
+
        /* Enable measurements at ~ 10 Hz */
        regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
        measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
@@ -478,6 +496,8 @@ static int imx_thermal_remove(struct platform_device *pdev)
 
        /* Disable measurements */
        regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
+       if (!IS_ERR(data->thermal_clk))
+               clk_disable_unprepare(data->thermal_clk);
 
        thermal_zone_device_unregister(data->tz);
        cpufreq_cooling_unregister(data->cdev);
@@ -490,27 +510,30 @@ static int imx_thermal_suspend(struct device *dev)
 {
        struct imx_thermal_data *data = dev_get_drvdata(dev);
        struct regmap *map = data->tempmon;
-       u32 val;
 
-       regmap_read(map, TEMPSENSE0, &val);
-       if ((val & TEMPSENSE0_POWER_DOWN) == 0) {
-               /*
-                * If a measurement is taking place, wait for a long enough
-                * time for it to finish, and then check again.  If it still
-                * does not finish, something must go wrong.
-                */
-               udelay(50);
-               regmap_read(map, TEMPSENSE0, &val);
-               if ((val & TEMPSENSE0_POWER_DOWN) == 0)
-                       return -ETIMEDOUT;
-       }
+       /*
+        * Need to disable thermal sensor, otherwise, when thermal core
+        * try to get temperature before thermal sensor resume, a wrong
+        * temperature will be read as the thermal sensor is powered
+        * down.
+        */
+       regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
+       regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
+       data->mode = THERMAL_DEVICE_DISABLED;
 
        return 0;
 }
 
 static int imx_thermal_resume(struct device *dev)
 {
-       /* Nothing to do for now */
+       struct imx_thermal_data *data = dev_get_drvdata(dev);
+       struct regmap *map = data->tempmon;
+
+       /* Enabled thermal sensor after resume */
+       regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
+       regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
+       data->mode = THERMAL_DEVICE_ENABLED;
+
        return 0;
 }
 #endif
@@ -522,6 +545,7 @@ static const struct of_device_id of_imx_thermal_match[] = {
        { .compatible = "fsl,imx6q-tempmon", },
        { /* end */ }
 };
+MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
 
 static struct platform_driver imx_thermal = {
        .driver = {