If a irq is already disabled, irq_shutdown may try to disable it again,
for example:
devm_request_irq->irq_startup->irq_enable
disable_irq <-- disabled
devm_free_irq->irq_shutdown <-- disable it again
This would confuse some chips which require balanced irq enable and
disable, for example pinctrl-rockchip & pinctrl-nomadik.
Add a state check before calling irq_disable to prevent that.
v2: Rewrite commit message.
v3: Rewrite commit message and not skip irq_shutdown.
Signed-off-by: Jeffy Chen <jeffy.c...@rock-chips.com>
---
Changes in v3:
Rewrite commit message and not skip irq_shutdown.
Changes in v2:
Rewrite commit message.
kernel/irq/chip.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 686be4b..0ac0c56 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -206,13 +206,23 @@ int irq_startup(struct irq_desc *desc, bool resend)
void irq_shutdown(struct irq_desc *desc)
{
+ int irq_disabled = irqd_irq_disabled(&desc->irq_data);
+
irq_state_set_disabled(desc);
desc->depth = 1;
if (desc->irq_data.chip->irq_shutdown)
desc->irq_data.chip->irq_shutdown(&desc->irq_data);
- else if (desc->irq_data.chip->irq_disable)
+ /*
+ * 1/ Some chips may require balanced irq enable &_disable.
+ * 2/ Due to the lazy disable approach, a irq could be
+ * disabled but unmasked.
+ *
+ * So if this irq is already disabled, let's mask it instead
+ * of trying to call irq_disable again.
+ */
+ else if (desc->irq_data.chip->irq_disable && !irq_disabled)
desc->irq_data.chip->irq_disable(&desc->irq_data);
- else
+ else if (desc->irq_data.chip->irq_mask)
desc->irq_data.chip->irq_mask(&desc->irq_data);
irq_domain_deactivate_irq(&desc->irq_data);
irq_state_set_masked(desc);
--
2.1.4
