diff options
Diffstat (limited to 'drivers/thermal/imx_thermal.c')
| -rw-r--r-- | drivers/thermal/imx_thermal.c | 54 |
1 files changed, 39 insertions, 15 deletions
diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c index 1d6c801c1eb9..45af765a3198 100644 --- 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 = { |