| Message ID | 20201210212534.216197-13-krzk@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/18] ARM: dts: exynos: correct fuel gauge interrupt trigger level on GT-I9100 | expand |
On Thu, 10 Dec 2020 22:25:29 +0100, Krzysztof Kozlowski wrote: > 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> > > --- > > This patch should wait till DTS changes are merged, as it relies on > proper Devicetree. > --- > Documentation/devicetree/bindings/clock/maxim,max77686.txt | 4 ++-- > Documentation/devicetree/bindings/mfd/max77686.txt | 2 +- > Documentation/devicetree/bindings/regulator/max77686.txt | 2 +- > drivers/mfd/max77686.c | 3 +-- > 4 files changed, 5 insertions(+), 6 deletions(-) > Acked-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/clock/maxim,max77686.txt b/Documentation/devicetree/bindings/clock/maxim,max77686.txt index 3472b461ca93..c10849efb444 100644 --- 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 42968b7144e0..4447d074894a 100644 --- 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 e9f7578ca09a..ff3d2dec8c4b 100644 --- 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 2ad554b921d9..f9e12ab2bc75 100644 --- 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);
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> --- This patch should wait till DTS changes are merged, as it relies on proper Devicetree. --- Documentation/devicetree/bindings/clock/maxim,max77686.txt | 4 ++-- Documentation/devicetree/bindings/mfd/max77686.txt | 2 +- Documentation/devicetree/bindings/regulator/max77686.txt | 2 +- drivers/mfd/max77686.c | 3 +-- 4 files changed, 5 insertions(+), 6 deletions(-)