linux-kernel - Re: [PATCH RESEND v5 0/7] Input: synaptics-rmi4 - add quirks for third party touchscreen controllers

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] [day] [month] [year] [list]

Message-ID: <aggtzmlxvj4so6t7trlo5ianjcbq2jrsodv6hlkhtrvgl2qpqj@gflvqocxjckb>
Date: Wed, 6 Aug 2025 21:29:14 -0700
From: Dmitry Torokhov <dmitry.torokhov@...il.com>
To: david@...t.cz
Cc: Kaustabh Chakraborty <kauschluss@...root.org>, 
	Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
	Conor Dooley <conor+dt@...nel.org>, "Jason A. Donenfeld" <Jason@...c4.com>, 
	Matthias Schiffer <matthias.schiffer@...tq-group.com>, Vincent Huang <vincent.huang@...synaptics.com>, 
	linux-input@...r.kernel.org, devicetree@...r.kernel.org, linux-kernel@...r.kernel.org, 
	phone-devel@...r.kernel.org, ~postmarketos/upstreaming@...ts.sr.ht, 
	Casey Connolly <casey.connolly@...aro.org>, Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
Subject: Re: [PATCH RESEND v5 0/7] Input: synaptics-rmi4 - add quirks for
 third party touchscreen controllers

Hi David,

On Thu, Jul 31, 2025 at 11:06:50PM +0200, David Heidelberg via B4 Relay wrote:
> With the growing popularity of running upstream Linux on mobile devices,
> we're beginning to run into more and more edgecases. The OnePlus 6 is a
> fairly well supported 2018 era smartphone, selling over a million units
> in it's first 22 days. With this level of popularity, it's almost
> inevitable that we get third party replacement displays, and as a
> result, replacement touchscreen controllers.
> 
> The OnePlus 6 shipped with an extremely usecase specific touchscreen
> driver, it implemented only the bare minimum parts of the highly generic
> rmi4 protocol, instead hardcoding most of the register addresses.
> 
> As a result, the third party touchscreen controllers that are often
> found in replacement screens, implement only the registers that the
> downstream driver reads from. They additionally have other restrictions
> such as heavy penalties on unaligned reads.
> 
> This series attempts to implement the necessary workaround to support
> some of these chips with the rmi4 driver. Although it's worth noting
> that at the time of writing there are other unofficial controllers in
> the wild that don't work even with these patches.
> 
> We have been shipping these patches in postmarketOS for the last several
> years, and they are known to not cause any regressions on the OnePlus
> 6/6T (with the official Synaptics controller), however I don't own any
> other rmi4 hardware to further validate this.

Sorry for not handling the patches in the last few submissions. I am
planning on addressing them once merge window opens.

Thanks.

-- 
Dmitry