linux-kernel - [PATCH] rtc: pcf2127: use IRQ flags obtained from device tree if available

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Message-Id: <20220117225742.1252362-1-hugo@hugovil.com>
Date:   Mon, 17 Jan 2022 17:57:42 -0500
From:   Hugo Villeneuve <hugo@...ovil.com>
To:     Alessandro Zummo <a.zummo@...ertech.it>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc:     hugo@...ovil.com, Hugo Villeneuve <hvilleneuve@...onoff.com>,
        linux-rtc@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] rtc: pcf2127: use IRQ flags obtained from device tree if available

From: Hugo Villeneuve <hvilleneuve@...onoff.com>

If the interrupt pin of the PCF2127 is routed to the input of a GPIO
expander using the pca953x driver, the later will only accept an IRQ
of type IRQ_TYPE_EDGE_FALLING or IRQ_TYPE_EDGE_RISING, and the IRQ
request will fail.

Therefore, allow the IRQ type to be passed from the device tree data
if available.

Signed-off-by: Hugo Villeneuve <hvilleneuve@...onoff.com>
---
 drivers/rtc/rtc-pcf2127.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index e6d0838ccfe3..cea10fdbb010 100644
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -659,9 +659,20 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
 	clear_bit(RTC_FEATURE_ALARM, pcf2127->rtc->features);
 
 	if (alarm_irq > 0) {
+		unsigned long flags;
+
+		/*
+		 * If flags = 0, devm_request_threaded_irq() will use IRQ flags
+		 * obtained from device tree.
+		 */
+		if (dev_fwnode(dev))
+			flags = 0;
+		else
+			flags = IRQF_TRIGGER_LOW;
+
 		ret = devm_request_threaded_irq(dev, alarm_irq, NULL,
 						pcf2127_rtc_irq,
-						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						flags | IRQF_ONESHOT,
 						dev_name(dev), dev);
 		if (ret) {
 			dev_err(dev, "failed to request alarm irq\n");
-- 
2.30.2