linux-kernel - [PATCH v2 7/7] power: supply: max17040: Do not enforce (incorrect) interrupt trigger type

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Date:   Wed, 26 May 2021 13:20:36 -0400
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...onical.com>
To:     Chanwoo Choi <cw00.choi@...sung.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@...onical.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Lee Jones <lee.jones@...aro.org>,
        Sebastian Reichel <sre@...nel.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>,
        Alessandro Zummo <a.zummo@...ertech.it>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org,
        devicetree@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-samsung-soc@...r.kernel.org, linux-rtc@...r.kernel.org
Cc:     Krzysztof Kozlowski <krzk@...nel.org>,
        Iskren Chernev <iskren.chernev@...il.com>
Subject: [PATCH v2 7/7] power: supply: max17040: Do not enforce (incorrect) interrupt trigger type

From: Krzysztof Kozlowski <krzk@...nel.org>

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@...nel.org>
Acked-by: Iskren Chernev <iskren.chernev@...il.com>

---

Changes since v1:
1. Remove the 'flags' variable.
2. Added ack.
3. Rebase - the bindings were converted to dtschema.
---
 .../devicetree/bindings/power/supply/maxim,max17040.yaml      | 2 +-
 drivers/power/supply/max17040_battery.c                       | 4 +---
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/power/supply/maxim,max17040.yaml b/Documentation/devicetree/bindings/power/supply/maxim,max17040.yaml
index de91cf3f058c..f792d06db413 100644
--- a/Documentation/devicetree/bindings/power/supply/maxim,max17040.yaml
+++ b/Documentation/devicetree/bindings/power/supply/maxim,max17040.yaml
@@ -89,7 +89,7 @@ examples:
         reg = <0x36>;
         maxim,alert-low-soc-level = <10>;
         interrupt-parent = <&gpio7>;
-        interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+        interrupts = <2 IRQ_TYPE_LEVEL_LOW>;
         wakeup-source;
       };
     };
diff --git a/drivers/power/supply/max17040_battery.c b/drivers/power/supply/max17040_battery.c
index 1aab868adabf..e80dd9141ae7 100644
--- a/drivers/power/supply/max17040_battery.c
+++ b/drivers/power/supply/max17040_battery.c
@@ -361,12 +361,10 @@ static irqreturn_t max17040_thread_handler(int id, void *dev)
 static int max17040_enable_alert_irq(struct max17040_chip *chip)
 {
 	struct i2c_client *client = chip->client;
-	unsigned int flags;
 	int ret;
 
-	flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
 	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;
-- 
2.27.0