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From:   Jeff LaBundy <jeff@labundy.com>
To:     lee.jones@linaro.org
Cc:     linux-kernel@vger.kernel.org, Jeff LaBundy <jeff@labundy.com>
Subject: [PATCH v2 4/6] mfd: iqs62x: Increase interrupt handler return delay
Date:   Sun, 17 Jan 2021 21:57:06 -0600
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The time the device takes to deassert its RDY output following an
I2C stop condition scales with the core clock frequency.

To prevent level-triggered interrupts from being reasserted after
the interrupt handler returns, increase the time before returning
to account for the worst-case delay (~90 us) plus margin.

Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
---
Changes in v2:
  - Added Acked-for-MFD-by trailer

 drivers/mfd/iqs62x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/iqs62x.c b/drivers/mfd/iqs62x.c
index 7a1ff7c..07c9725 100644
--- a/drivers/mfd/iqs62x.c
+++ b/drivers/mfd/iqs62x.c
@@ -533,7 +533,7 @@ static irqreturn_t iqs62x_irq(int irq, void *context)
 	 * ensure the device's RDY output has been deasserted by the time the
 	 * interrupt handler returns.
 	 */
-	usleep_range(50, 100);
+	usleep_range(150, 200);

 	return IRQ_HANDLED;
 }
--
2.7.4