Re: [PATCH v5] Fix freeze in lm8333 i2c keyboard driver

On Wed, May 03, 2023 at 08:44:06PM -0500, Jeff LaBundy wrote:

Hi Tomas,

On Wed, May 03, 2023 at 05:32:31PM +0200, Tomas Mudrunka wrote:

quoted

LM8333 uses gpio interrupt line which is triggered by falling edge.
When button is pressed before driver is loaded,
driver will miss the edge and never respond again.
To fix this we run the interrupt handler before registering IRQ
to clear the interrupt via i2c command.

Signed-off-by: Tomas Mudrunka <redacted>
---

Reviewed-by: Jeff LaBundy <redacted>

quoted

 drivers/input/keyboard/lm8333.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/input/keyboard/lm8333.c b/drivers/input/keyboard/lm8333.c
index 7457c3220..52108c370 100644
--- a/drivers/input/keyboard/lm8333.c
+++ b/drivers/input/keyboard/lm8333.c

@@ -178,6 +178,8 @@ static int lm8333_probe(struct i2c_client *client)
 			dev_warn(&client->dev, "Unable to set active time\n");
 	}
 
+	lm8333_irq_thread(client->irq, lm8333);

So this is still racy, isn't it? The interrupt may come after read is
done, but before we register the handler.

quoted

+
 	err = request_threaded_irq(client->irq, NULL, lm8333_irq_thread,
 				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 				   "lm8333", lm8333);
-- 
2.40.1

Thanks.

-- 
Dmitry