Re: [PATCH v10 31/55] Input: atmel_mxt_ts - delay enabling IRQ when not using regulators

[Wang, Jiada]

Hi Dmitry

On 2020/04/11 7:38, Dmitry Osipenko wrote:
> 31.03.2020 13:50, Jiada Wang ÐÐÑÐÑ:
> > 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