linux-kernel - Re: [PATCH v3 12/12] i2c: qcom-geni: Enable I2C on SA8255p Qualcomm platforms

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]

Message-ID: <8e410852-37f2-452b-b851-19b7c4222727@oss.qualcomm.com>
Date: Fri, 30 Jan 2026 13:34:47 +0100
From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
To: Praveen Talari <praveen.talari@....qualcomm.com>,
        Andi Shyti <andi.shyti@...nel.org>, Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley
 <conor+dt@...nel.org>,
        Mukesh Kumar Savaliya <mukesh.savaliya@....qualcomm.com>,
        Viken Dadhaniya <viken.dadhaniya@....qualcomm.com>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>, linux-arm-msm@...r.kernel.org,
        linux-i2c@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, bryan.odonoghue@...aro.org,
        dmitry.baryshkov@....qualcomm.com, bjorn.andersson@....qualcomm.com
Cc: prasad.sodagudi@....qualcomm.com, quic_vtanuku@...cinc.com,
        aniket.randive@....qualcomm.com, chandana.chiluveru@....qualcomm.com
Subject: Re: [PATCH v3 12/12] i2c: qcom-geni: Enable I2C on SA8255p Qualcomm
 platforms

On 1/12/26 11:47 AM, Praveen Talari wrote:
> The Qualcomm automotive SA8255p SoC relies on firmware to configure
> platform resources, including clocks, interconnects and TLMM.
> The driver requests resources operations over SCMI using power
> and performance protocols.
> 
> The SCMI power protocol enables or disables resources like clocks,
> interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs,
> such as resume/suspend, to control power on/off.
> 
> The SCMI performance protocol manages I2C frequency, with each
> frequency rate represented by a performance level. The driver uses
> geni_se_set_perf_opp() API to request the desired frequency rate..
> 
> As part of geni_se_set_perf_opp(), the OPP for the requested frequency
> is obtained using dev_pm_opp_find_freq_floor() and the performance
> level is set using dev_pm_opp_set_opp().
> 
> Signed-off-by: Praveen Talari <praveen.talari@....qualcomm.com>
> ---

[...]

> +static const struct geni_i2c_desc sa8255p_geni_i2c = {
> +	.resources_init = geni_se_domain_attach,
> +	.set_rate = geni_se_set_perf_opp,

This means, on SCMI devices you won't don't the vote on the POWER
domain (or PERF for that matter) and switch the GPIOs to a _suspend
state - is that by design?

Konrad