| Message ID | 20201210212534.216197-17-krzk@kernel.org |
|---|---|
| State | Accepted |
| Commit | 8163fbd97144a488b1edd1776765eec394b0cf17 |
| Headers | show |
| Series | [01/18] ARM: dts: exynos: correct fuel gauge interrupt trigger level on GT-I9100 | expand |
On Thu, 10 Dec 2020 22:25:33 +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 14577/77836 datasheets describe 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 charger 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/mfd/max14577.txt | 4 ++-- > drivers/mfd/max14577.c | 6 +++--- > 2 files changed, 5 insertions(+), 5 deletions(-) > Acked-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/mfd/max14577.txt b/Documentation/devicetree/bindings/mfd/max14577.txt index 92070b346756..be11943a0560 100644 --- a/Documentation/devicetree/bindings/mfd/max14577.txt +++ b/Documentation/devicetree/bindings/mfd/max14577.txt @@ -71,7 +71,7 @@ max14577@25 { compatible = "maxim,max14577"; reg = <0x25>; interrupt-parent = <&gpx1>; - interrupts = <5 IRQ_TYPE_NONE>; + interrupts = <5 IRQ_TYPE_LEVEL_LOW>; muic: max14577-muic { compatible = "maxim,max14577-muic"; @@ -106,7 +106,7 @@ max77836@25 { compatible = "maxim,max77836"; reg = <0x25>; interrupt-parent = <&gpx1>; - interrupts = <5 IRQ_TYPE_NONE>; + interrupts = <5 IRQ_TYPE_LEVEL_LOW>; muic: max77836-muic { compatible = "maxim,max77836-muic"; diff --git a/drivers/mfd/max14577.c b/drivers/mfd/max14577.c index be185e9d5f16..6c487fa14e9c 100644 --- a/drivers/mfd/max14577.c +++ b/drivers/mfd/max14577.c @@ -332,7 +332,7 @@ static int max77836_init(struct max14577 *max14577) } ret = regmap_add_irq_chip(max14577->regmap_pmic, max14577->irq, - IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED, + IRQF_ONESHOT | IRQF_SHARED, 0, &max77836_pmic_irq_chip, &max14577->irq_data_pmic); if (ret != 0) { @@ -418,14 +418,14 @@ static int max14577_i2c_probe(struct i2c_client *i2c, irq_chip = &max77836_muic_irq_chip; mfd_devs = max77836_devs; mfd_devs_size = ARRAY_SIZE(max77836_devs); - irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED; + irq_flags = IRQF_ONESHOT | IRQF_SHARED; break; case MAXIM_DEVICE_TYPE_MAX14577: default: irq_chip = &max14577_irq_chip; mfd_devs = max14577_devs; mfd_devs_size = ARRAY_SIZE(max14577_devs); - irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT; + irq_flags = IRQF_ONESHOT; break; }
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 14577/77836 datasheets describe 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 charger 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/mfd/max14577.txt | 4 ++-- drivers/mfd/max14577.c | 6 +++--- 2 files changed, 5 insertions(+), 5 deletions(-)