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 <[email protected]>
---
drivers/base/regmap/regmap-irq.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index d10456f..763c60d 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)
--
1.7.9.5
On Tue, Oct 22, 2013 at 06:44:32PM +0800, Yi Zhang wrote:
> clear the status bit if the mask register doesn't prevent
> the chip level irq from being asserted
Applied, thanks.