Re: [PATCH v11 4/8] Input: goodix - add power management support

From: Rafael J. Wysocki
Date: Thu Nov 19 2015 - 17:18:15 EST


Hi,

On Thu, Nov 19, 2015 at 7:24 PM, Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
> On Thu, Nov 19, 2015 at 02:26:37PM +0200, Irina Tirdea wrote:
>> Implement suspend/resume for goodix driver.
>>

[cut]

>>
>> +static int __maybe_unused goodix_suspend(struct device *dev)
>> +{
>> + struct i2c_client *client = to_i2c_client(dev);
>> + struct goodix_ts_data *ts = i2c_get_clientdata(client);
>> + int error;
>> +
>> + /* We need gpio pins to suspend/resume */
>> + if (!ts->gpiod_int || !ts->gpiod_rst)
>> + return 0;
>> +
>> + wait_for_completion(&ts->firmware_loading_complete);
>
> This is not that nice as it may lead to angry splats from the PM core if
> firmware loading takes too long and we start suspending before it
> completes.

What exactly do you mean? The suspend watchdog or something else?

> Rafael, if we issue pm_stay_awake() before requesting firmware and
> pm_relax() once it is done, will this prevent the current suspend
> timeouts?

pm_stay_awake() only works if the checking of wakeup sources is
enabled which generally depends on what user space does.

Thanks,
Rafael
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