When we come out of system suspend state (S3) the tsadc will have been reset and back at its default state. While reprogramming the tsadc it's possible that we'll glitch the output and unintentionally cause the "over temperature" GPIO to be asserted. Since the over temperature GPIO is often hooked up to something that will cause a reboot or shutdown in hardware, this glitch can be catastrophic on some boards. We'll add support for selecting the "sleep" pinctrl state at suspend time. Boards can use this to effectively disable the tsadc at suspend time and avoid glitches when the system is resumed. Signed-off-by: Caesar Wang <wxt at rock-chips.com> --- Changes in v4: - take the Doug's commit as correct decription. Changes in v3: - Add the pinctrl state for in the suspend/resume. Changes in v2: None Changes in v1: None drivers/thermal/rockchip_thermal.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/thermal/rockchip_thermal.c b/drivers/thermal/rockchip_thermal.c index c89ffb2..3b8fbda 100644 --- a/drivers/thermal/rockchip_thermal.c +++ b/drivers/thermal/rockchip_thermal.c @@ -642,6 +642,8 @@ static int __maybe_unused rockchip_thermal_suspend(struct device *dev) clk_disable(thermal->pclk); clk_disable(thermal->clk); + pinctrl_pm_select_sleep_state(dev); + return 0; } @@ -678,6 +680,8 @@ static int __maybe_unused rockchip_thermal_resume(struct device *dev) for (i = 0; i < ARRAY_SIZE(thermal->sensors); i++) rockchip_thermal_toggle_sensor(&thermal->sensors[i], true); + pinctrl_pm_select_default_state(dev); + return 0; } -- 1.9.1
