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Subject: Re: [PATCH] Fix resume for ELAN2097 touchscreen.
From:   Kai-Heng Feng <kai.heng.feng@canonical.com>
In-Reply-To: <nycvar.YFH.7.76.1902150834180.11598@cbobk.fhfr.pm>
Date:   Fri, 15 Feb 2019 17:24:57 +0800
Cc:     Benjamin Tissoires <benjamin.tissoires@gmail.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>
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References: <20190211070040.4569-1-jbroadus@gmail.com>
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To:     Jiri Kosina <jikos@kernel.org>, james broadus <jbroadus@gmail.com>
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Hi Jiri and James,

> On Feb 15, 2019, at 15:35, Jiri Kosina <jikos@kernel.org> wrote:
> 
> On Thu, 14 Feb 2019, james broadus wrote:
> 
>>> This should be fixed in hid.git#for-5.1/i2c-hid already by commit
>>> 1475af255e18f. Could you please confirm that?
>>> 
>> 
>> Hi Jiri. That change mutes the log messages, but I'm still counting 
>> around 35000 interrupts per second after resume and touch does not work. 
>> With the reset, the device works properly.
> 
> Ah, I see. Should your patch then actually replace 1475af255e18f?

Sorry for the late reply, was off because of Lunar new year.

Commit 1475af255e18f is to silence the message when using the touchpad, so it’s different to this patch.

I’ve seen similar bugs happens on new platforms that defaults S2Idle (Modern Standby), but user uses S3 instead.
On those systems, S3 was never tested, so the BIOS doesn’t cut the touchpad’s power off during S3, and the IRQ line wasn’t getting properly reset.

So if the platform defaults to S2Idle but user wants to use S3, this issue happens.
If that’s the case, maybe it’s better to report to the platform vendor.

Kai-Heng

> 
> Thanks,
> 
> -- 
> Jiri Kosina
> SUSE Labs
>