From 52473b07401891fd963db44ca691ec9ec441546c Mon Sep 17 00:00:00 2001 From: Marek Czerski Date: Wed, 3 Feb 2021 22:49:00 +0100 Subject: [PATCH] power: reset: ltc2952: make trigger delay configurable Make trigger delay configurable through device tree with trigger-delay-ms property. Trigger delay is the time to wait before starting shutdown sequence after trigger line assertion. Trigger delay must take into account the OFFT time configured with the capacitor connected to OFFT pin of the LTC2952 chip. Basically, the higher the capacitance connected to OFFT pin, the larger trigger delay must be. Signed-off-by: Marek Czerski Acked-by: Rob Herring Signed-off-by: Sebastian Reichel --- .../devicetree/bindings/power/reset/ltc2952-poweroff.txt | 4 ++++ drivers/power/reset/ltc2952-poweroff.c | 8 ++++++++ 2 files changed, 12 insertions(+) diff --git a/Documentation/devicetree/bindings/power/reset/ltc2952-poweroff.txt b/Documentation/devicetree/bindings/power/reset/ltc2952-poweroff.txt index cd2d7f5..38e54b3 100644 --- a/Documentation/devicetree/bindings/power/reset/ltc2952-poweroff.txt +++ b/Documentation/devicetree/bindings/power/reset/ltc2952-poweroff.txt @@ -17,6 +17,9 @@ Optional properties: chip's trigger line. If this property is not set, the trigger function is ignored and the chip is kept alive until an explicit kill signal is received +- trigger-delay-ms The number of milliseconds to wait after trigger line + assertion before executing shut down procedure. + The default is 2500ms. Example: @@ -24,6 +27,7 @@ ltc2952 { compatible = "lltc,ltc2952"; trigger-gpios = <&gpio0 1 GPIO_ACTIVE_LOW>; + trigger-delay-ms = <2000>; watchdog-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>; kill-gpios = <&gpio0 2 GPIO_ACTIVE_LOW>; }; diff --git a/drivers/power/reset/ltc2952-poweroff.c b/drivers/power/reset/ltc2952-poweroff.c index 3189279..d1495af 100644 --- a/drivers/power/reset/ltc2952-poweroff.c +++ b/drivers/power/reset/ltc2952-poweroff.c @@ -55,6 +55,7 @@ #include #include #include +#include struct ltc2952_poweroff { struct hrtimer timer_trigger; @@ -172,10 +173,17 @@ static void ltc2952_poweroff_default(struct ltc2952_poweroff *data) static int ltc2952_poweroff_init(struct platform_device *pdev) { int ret; + u32 trigger_delay_ms; struct ltc2952_poweroff *data = platform_get_drvdata(pdev); ltc2952_poweroff_default(data); + if (!device_property_read_u32(&pdev->dev, "trigger-delay-ms", + &trigger_delay_ms)) { + data->trigger_delay = ktime_set(trigger_delay_ms / MSEC_PER_SEC, + (trigger_delay_ms % MSEC_PER_SEC) * NSEC_PER_MSEC); + } + data->gpio_watchdog = devm_gpiod_get(&pdev->dev, "watchdog", GPIOD_OUT_LOW); if (IS_ERR(data->gpio_watchdog)) { -- 2.7.4