[RFC 18/18] power: supply: max17040: Do not enforce (incorrect) interrupt trigger type
iskren.chernev at gmail.com
Fri Dec 11 10:44:26 EST 2020
On 12/11/20 9:47 AM, Krzysztof Kozlowski wrote:
> On Thu, Dec 10, 2020 at 10:25:34PM +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.
>> Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
>> This patch should wait till DTS changes are merged, as it relies on
>> proper Devicetree.
>> .../devicetree/bindings/power/supply/max17040_battery.txt | 2 +-
>> drivers/power/supply/max17040_battery.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>> diff --git
>> index c802f664b508..194eb9fe574d 100644
>> @@ -39,7 +39,7 @@ Example:
>> reg = <0x36>;
>> maxim,alert-low-soc-level = <10>;
>> interrupt-parent = <&gpio7>;
>> - interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
>> + interrupts = <2 IRQ_TYPE_LEVEL_LOW>;
>> diff --git a/drivers/power/supply/max17040_battery.c
>> index d956c67d5155..f737de0470de 100644
>> --- a/drivers/power/supply/max17040_battery.c
>> +++ b/drivers/power/supply/max17040_battery.c
>> @@ -367,7 +367,7 @@ static int max17040_enable_alert_irq(struct
>> flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
> This has to be removed. I will fix it in v2.
> Best regards,
I removed the IRQF_TRIGGER_FALLING, tweaked the DT as per the DT patch, and
it worked on the samsung klte.
I don't understand how the DT irq flag ends up being used by the kernel. It
is never explicitly read from DT or passed to interrupt API, only i2c->irq,
which is a pure int.
Fixing the DT and the drivers will hopefully set a precedent, so future
drivers (when copied/tweaked from existing drivers) will do it right.
Acked-by: Iskren Chernev <iskren.chernev at gmail.com>
>> ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
>> - max17040_thread_handler, flags,
>> + max17040_thread_handler, IRQF_ONESHOT,
>> chip->battery->desc->name, chip);
>> return ret;
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