mfd: max77686: Do not enforce (incorrect) interrupt trigger type

Interrupt line can be configured on different hardware in different way,
even inverted.  Therefore driver should not enforce specific trigger
type - edge falling - but instead rely on Devicetree to configure it.

The Maxim 77686 datasheet describes the interrupt line as active low
with a requirement of acknowledge from the CPU therefore the edge
falling is not correct.

The interrupt line is shared between PMIC and RTC driver, so using level
sensitive interrupt is here especially important to avoid races.  With
an edge configuration in case if first PMIC signals interrupt followed
shortly after by the RTC, the interrupt might not be yet cleared/acked
thus the second one would not be noticed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210602110445.33536-2-krzysztof.kozlowski@canonical.com

diff --git a/Documentation/devicetree/bindings/clock/maxim,max77686.txt b/Documentation/devicetree/bindings/clock/maxim,max77686.txt
index 3472b46..c10849e 100644 (file)
--- a/Documentation/devicetree/bindings/clock/maxim,max77686.txt
+++ b/Documentation/devicetree/bindings/clock/maxim,max77686.txt
@@ -49,7 +49,7 @@ Example:
                max77686: max77686@9 {
                        compatible = "maxim,max77686";
                        interrupt-parent = <&wakeup_eint>;
-                       interrupts = <26 0>;
+                       interrupts = <26 IRQ_TYPE_LEVEL_LOW>;
                        reg = <0x09>;
                        #clock-cells = <1>;
 
@@ -74,7 +74,7 @@ Example:
                max77802: max77802@9 {
                        compatible = "maxim,max77802";
                        interrupt-parent = <&wakeup_eint>;
-                       interrupts = <26 0>;
+                       interrupts = <26 IRQ_TYPE_LEVEL_LOW>;
                        reg = <0x09>;
                        #clock-cells = <1>;
 

diff --git a/Documentation/devicetree/bindings/mfd/max77686.txt b/Documentation/devicetree/bindings/mfd/max77686.txt
index 42968b7..4447d07 100644 (file)
--- a/Documentation/devicetree/bindings/mfd/max77686.txt
+++ b/Documentation/devicetree/bindings/mfd/max77686.txt
@@ -21,6 +21,6 @@ Example:
        max77686: pmic@9 {
                compatible = "maxim,max77686";
                interrupt-parent = <&wakeup_eint>;
-               interrupts = <26 0>;
+               interrupts = <26 IRQ_TYPE_LEVEL_LOW>;
                reg = <0x09>;
        };

diff --git a/Documentation/devicetree/bindings/regulator/max77686.txt b/Documentation/devicetree/bindings/regulator/max77686.txt
index e9f7578..ff3d2de 100644 (file)
--- a/Documentation/devicetree/bindings/regulator/max77686.txt
+++ b/Documentation/devicetree/bindings/regulator/max77686.txt
@@ -43,7 +43,7 @@ Example:
        max77686: pmic@9 {
                compatible = "maxim,max77686";
                interrupt-parent = <&wakeup_eint>;
-               interrupts = <26 IRQ_TYPE_NONE>;
+               interrupts = <26 IRQ_TYPE_LEVEL_LOW>;
                reg = <0x09>;
 
                voltage-regulators {

diff --git a/drivers/mfd/max77686.c b/drivers/mfd/max77686.c
index 2ad554b..f9e12ab 100644 (file)
--- a/drivers/mfd/max77686.c
+++ b/drivers/mfd/max77686.c
@@ -209,8 +209,7 @@ static int max77686_i2c_probe(struct i2c_client *i2c)
 
        ret = devm_regmap_add_irq_chip(&i2c->dev, max77686->regmap,
                                       max77686->irq,
-                                      IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
-                                      IRQF_SHARED, 0, irq_chip,
+                                      IRQF_ONESHOT | IRQF_SHARED, 0, irq_chip,
                                       &max77686->irq_data);
        if (ret < 0) {
                dev_err(&i2c->dev, "failed to add PMIC irq chip: %d\n", ret);