Re: [PATCH] HID: i2c-hid: add polling mode based on connected GPIO chip's pin status

From: Barnabás Pőcze
Date: Thu Oct 15 2020 - 06:34:02 EST


Hi,

I believe this patch causes I2C HID devices not to work with IRQs after resuming
from suspend.


> [...]
> #ifdef CONFIG_PM_SLEEP
> @@ -1183,7 +1292,8 @@ static int i2c_hid_suspend(struct device *dev)
> /* Save some power */
> i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
>
> - disable_irq(client->irq);
> + if (polling_mode == I2C_POLLING_DISABLED)
> + disable_irq(client->irq);
>

The IRQ is disabled when suspending if polling is *off*.


> if (device_may_wakeup(&client->dev)) {
> wake_status = enable_irq_wake(client->irq);
> @@ -1216,7 +1326,7 @@ static int i2c_hid_resume(struct device *dev)
>
> if (ihid->pdata.post_power_delay_ms)
> msleep(ihid->pdata.post_power_delay_ms);
> - } else if (ihid->irq_wake_enabled) {
> + } else if (ihid->irq_wake_enabled && polling_mode != I2C_POLLING_DISABLED) {

As a side note, I'm not sure if the 'polling_mode != I2C_POLLING_DISABLED' part
is necessary (or that it's necessary *here*). It causes 'i2c_hid_resume' and
'i2c_hid_suspend' to be "asymmetric" which - I believe - may cause problems.


> wake_status = disable_irq_wake(client->irq);
> if (!wake_status)
> ihid->irq_wake_enabled = false;
> @@ -1225,7 +1335,8 @@ static int i2c_hid_resume(struct device *dev)
> wake_status);
> }
>
> - enable_irq(client->irq);
> + if (polling_mode != I2C_POLLING_DISABLED)
> + enable_irq(client->irq);
>

The IRQ is enabled when resuming if polling is *on*. It should be enabled if polling is *off*
in my opinion.


> [...]


Regards,
Barnabás Pőcze