Hi Dmitry
On 2020/04/11 7:38, Dmitry Osipenko wrote:
31.03.2020 13:50, Jiada Wang пишет:
From: Nick Dyer <nick.dyer@xxxxxxxxxxx>
The path of enabling the IRQ in the probe function is not safe in level
triggered operation, if it was already powered up and there is a message
waiting on the device (eg finger down) because the object table has not yet
been read. This forces the ISR into a hard loop.
Delay enabling the interrupt until it is first needed.
- if (data->use_retrigen_workaround) {
+ /* Presence of data->irq means IRQ initialised */
+ data->irq = data->client->irq;
IIRC, IRQ=0 could be a valid interrupt since this is a "virtual"
interrupt number.
...
init_completion(&data->chg_completion);
@@ -3826,26 +3842,22 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
return error;
}
What about just to tell the IRQ core not to enable the interrupt
handling during of the devm_request_threaded_irq()?
To achieve that, add this line here:
irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
- error = devm_request_threaded_irq(&client->dev, client->irq,
- NULL, mxt_interrupt, IRQF_ONESHOT,
- client->name, data);
...
Then the interrupt will be requested in the disabled state and it will
be enabled only after the first enable_irq() invocation.
thanks, I think your solution makes more sense,
I will replace with your suggested solution in next version
Thanks,
Jiada
