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 <yizh...@marvell.com>
---
drivers/base/regmap/regmap-irq.c | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index d10456f..9b0148f 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -61,7 +61,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
{
struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
struct regmap *map = d->map;
- int i, ret;
+ int i, j, ret, bits_length;
u32 reg;
if (d->chip->runtime_pm) {
@@ -105,6 +105,31 @@ 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->chip->ack_base) {
+ reg = d->chip->ack_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+
+ bits_length = d->map->format.val_bytes * BITS_PER_BYTE;
+ for (j = 0; j < bits_length; j++) {
+ if (!(d->mask_buf[i] & (0x1 << j))) {
+ ret = regmap_update_bits(d->map, reg,
+ (0x1 << j), 0);
+ if (ret != 0)
+ dev_err(d->map->dev,
+ "Failed to ack 0x%x:
%d\n",
+ reg, ret);
+ }
+ }
+ /* no need to sync status_buf, update in irq handler */
+ }
}
if (d->chip->runtime_pm)
--
1.7.9.5
--
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