linux-kernel - Re: [PATCH] regmap: irq: Acknowledge also interrupts that are masked

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Date:	Mon, 22 Jul 2013 13:11:14 +0200
From:	Philipp Zabel <p.zabel@...gutronix.de>
To:	Mark Brown <broonie@...nel.org>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] regmap: irq: Acknowledge also interrupts that are masked

Hi Mark,

Am Montag, den 22.07.2013, 11:08 +0100 schrieb Mark Brown:
> On Mon, Jul 22, 2013 at 11:24:52AM +0200, Philipp Zabel wrote:
> > In case the hardware interrupt mask register does not prevent the chip level
> > irq from being asserted by the corresponding interrupt status bit, stray
> > masked interrupts should to be acknowledged, too.
> 
> > Signed-off-by: Philipp Zabel <p.zabel@...gutronix.de>
> > ---
> > I have seen GPI interrupts trigger on DA9063 trigger after being masked during
> > initialization, and once the status bits are set, the interrupt handler routine
> > never clears them, which keeps the chip irq line asserted forever.
> 
> This can't be the standard behaviour since it breaks expectations as to
> what happens for masked interrupts.  Though based on your description of
> the problem it sounds like a quirk to ack interrupts immediately after
> masking them might do the trick instead of the full on always ack
> behaviour.

thanks, this seems to work, too:

diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index 1643e88..4c99ed8 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -418,6 +418,24 @@ int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 				reg, ret);
 			goto err_alloc;
 		}
+
+		/* Ack masked but set interrupts */
+		reg = chip->status_base +
+			(i * map->reg_stride * d->irq_reg_stride);
+		ret = regmap_read(map, reg, &d->status_buf[i]);
+		if (ret != 0) {
+			dev_err(map->dev, "Failed to read IRQ status: %d\n",
+				ret);
+			goto err_alloc;
+		}
+
+		reg = chip->ack_base +
+			(i * map->reg_stride * d->irq_reg_stride);
+		ret = regmap_write(map, reg, d->status_buf[i] & d->mask_buf[i]);
+		if (ret != 0) {
+			dev_err(map->dev, "Failed to ack 0x%x: %d\n", reg, ret);
+			goto err_alloc;
+		}
 	}
 
 	/* Wake is disabled by default */
-- 
1.8.3.2

Can something like this be done unconditionally, or should I add a quirk
flag to regmap_irq_chip?

regards
Philipp

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