linux-kernel - Re: [PATCH v2] HID: i2c-hid: wait for i2c touchpad deep-sleep to power-up transition

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Mon, 15 Apr 2024 15:22:49 +0200
From: Johan Hovold <johan@...nel.org>
To: Kenny Levinsen <kl@...wtf>
Cc: lma@...omium.org, benjamin.tissoires@...hat.com, dianders@...omium.org,
	dtor@...omium.org, hdegoede@...hat.com, jikos@...nel.org,
	johan+linaro@...nel.org, kai.heng.feng@...onical.com,
	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
	mripard@...nel.org, rad@...omium.org
Subject: Re: [PATCH v2] HID: i2c-hid: wait for i2c touchpad deep-sleep to
 power-up transition

On Mon, Apr 15, 2024 at 12:28:28PM +0200, Kenny Levinsen wrote:
> > The problem is that the probe function calling i2c_smbus_read_byte()
> > is not aware that
> > uC on the other end is in a deep sleep state so the first read will
> > fail and so the whole probe.

> Well, the probe was just added to "avoid scary messages", so we could 
> just do away with it and fix the "scary messages" instead.

We also use it for devices that may not be populated (e.g. an optional
touchscreen) and in that case we should not print anything.

Johan