From 4bd7145b194af7cd96fc56d2ebee583b3edf03d3 Mon Sep 17 00:00:00 2001 From: Yi Zhang Date: Tue, 22 Oct 2013 18:44:32 +0800 Subject: regmap: irq: clear status when disable irq clear the status bit if the mask register doesn't prevent the chip level irq from being asserted OR in the following sequence, there will be irq storm happens: 1) interrupt is triggered; 2) another thread disables it(the mask bit is set); 3) _Then_ the interrupt thread is not ACKed(the status bit is not cleared), and it's ignored; 4) if the irq is still asserted because of the uncleared status bit, the irq storm happens; Signed-off-by: Yi Zhang Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-irq.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c index d10456ffd81..763c60d3d27 100644 --- a/drivers/base/regmap/regmap-irq.c +++ b/drivers/base/regmap/regmap-irq.c @@ -105,6 +105,22 @@ static void regmap_irq_sync_unlock(struct irq_data *data) "Failed to sync wakes in %x: %d\n", reg, ret); } + + if (!d->chip->init_ack_masked) + continue; + /* + * Ack all the masked interrupts uncondictionly, + * OR if there is masked interrupt which hasn't been Acked, + * it'll be ignored in irq handler, then may introduce irq storm + */ + if (d->mask_buf[i] && d->chip->ack_base) { + reg = d->chip->ack_base + + (i * map->reg_stride * d->irq_reg_stride); + ret = regmap_write(map, reg, d->mask_buf[i]); + if (ret != 0) + dev_err(d->map->dev, "Failed to ack 0x%x: %d\n", + reg, ret); + } } if (d->chip->runtime_pm) -- cgit v1.2.3-70-g09d2