From b46cce5902def84d35f3b043e89ab764f6c9746e Mon Sep 17 00:00:00 2001 From: Anson Huang Date: Tue, 24 Dec 2013 09:43:24 -0500 Subject: thermal: imx: correct suspend/resume flow Fixes regression introduced by: commit 37713a1e8e4c1a1067ad4c99296f78d3c82ed9c4 Author: Philipp Zabel Date: Thu Aug 1 18:33:12 2013 +0200 thermal: imx: implement thermal alarm interrupt handling The commit 37713a1e8e4 makes imx thermal sensor always powered up as alarm function is enabled, but the suspend callback of imx thermal returns success only if thermal sensor is powered down, so it will always returns fail hence break system's suspend, this patch disables imx thermal sensor before suspend and re-enable it after resume. Signed-off-by: Anson Huang Acked-by: Shawn Guo Signed-off-by: Zhang Rui --- drivers/thermal/imx_thermal.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-) (limited to 'drivers/thermal/imx_thermal.c') diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c index 1d6c801c1eb9..1f63c1fbcb49 100644 --- a/drivers/thermal/imx_thermal.c +++ b/drivers/thermal/imx_thermal.c @@ -490,27 +490,30 @@ 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 -- cgit v1.2.3