From: Mukesh Savaliya <mukesh.savaliya@oss.qualcomm.com>
To: Bjorn Andersson <andersson@kernel.org>
Cc: viken.dadhaniya@oss.qualcomm.com, andi.shyti@kernel.org,
robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org,
vkoul@kernel.org, Frank.Li@kernel.org, konradybcio@kernel.org,
dmitry.baryshkov@oss.qualcomm.com, linmq006@gmail.com,
quic_jseerapu@quicinc.com, agross@kernel.org,
linux-arm-msm@vger.kernel.org, linux-i2c@vger.kernel.org,
devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
dmaengine@vger.kernel.org, krzysztof.kozlowski@oss.qualcomm.com,
bartosz.golaszewski@oss.qualcomm.com,
bjorn.andersson@oss.qualcomm.com, konrad.dybcio@oss.qualcomm.com
Subject: Re: [PATCH v7 3/4] soc: qcom: geni-se: Keep pinctrl active for multi-owner controllers
Date: Mon, 25 May 2026 12:46:09 +0530 [thread overview]
Message-ID: <9a0a2ba2-4f1b-425d-979b-fe59192bb2cd@oss.qualcomm.com> (raw)
In-Reply-To: <ag_HGVQjIQuMoKO6@baldur>
Hi Bjorn, Thanks for the detailed review.
On 5/22/2026 8:36 AM, Bjorn Andersson wrote:
> On Thu, Apr 23, 2026 at 08:25:50PM +0530, Mukesh Kumar Savaliya wrote:
>> On platforms where a GENI Serial Engine is shared with another system
>> processor, selecting the "sleep" pinctrl state can disrupt ongoing
>> transfers initiated by the other processor.
>>
>
> Isn't it strange that the DeviceTree will define a sleep state for the
> OS to select, but when this other property is set the OS should never
> select this state?
>
The intent here is that for multi-owner configurations the
“sleep” pinctrl state is not safe to use, since the pins may
still be actively driven by another execution environment.
Selecting the sleep state in such cases can disrupt transfers
initiated by the other owner.
You're right that this constraint is currently not described
in the binding, which makes the behavior non-obvious.
shall i update the DT binding to clarify that when
"qcom,qup-multi-owner" is present ? The OS must not transition
the pins to the "sleep" state, as the hardware is shared and
may be active outside of Linux control.
Alternatively, we can also consider relaxing the requirement
to define a sleep state for such nodes if that aligns better
with DT expectations.
>> Teach geni_se_resources_off() to skip selecting the pinctrl sleep state
>> when the Serial Engine is marked as shared, while still allowing the
>> rest of the resource shutdown sequence to proceed.
>>
>> This is required for multi-owner configurations (described via DeviceTree
>> with qcom,qup-multi-owner on the protocol controller node).
>>
>
> The requirement as such is reasonable, but you don't define in the
> binding that when this property is set, the sleep state must not be
> selected by the OS...
>
Please let me know if you prefer second approach over the first, i shall
update accordingly.
> Regards,
> Bjorn
>
>> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
>> Signed-off-by: Mukesh Kumar Savaliya <mukesh.savaliya@oss.qualcomm.com>
>> ---
[...]
next prev parent reply other threads:[~2026-05-25 7:16 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-23 14:55 [PATCH v7 0/4] Enable multi-owner I2C support for QCOM GENI controllers Mukesh Kumar Savaliya
2026-04-23 14:55 ` [PATCH v7 1/4] dt-bindings: i2c: qcom,i2c-geni: Document multi-owner controller support Mukesh Kumar Savaliya
2026-04-23 14:55 ` [PATCH v7 2/4] dmaengine: qcom: gpi: Add lock/unlock TREs for multi-owner I2C transfers Mukesh Kumar Savaliya
2026-04-23 14:55 ` [PATCH v7 3/4] soc: qcom: geni-se: Keep pinctrl active for multi-owner controllers Mukesh Kumar Savaliya
2026-05-22 3:06 ` Bjorn Andersson
2026-05-25 7:16 ` Mukesh Savaliya [this message]
2026-06-15 10:54 ` Mukesh Savaliya
2026-04-23 14:55 ` [PATCH v7 4/4] i2c: qcom-geni: Support multi-owner controllers in GPI mode Mukesh Kumar Savaliya
2026-05-22 3:15 ` Bjorn Andersson
2026-05-25 7:19 ` Mukesh Savaliya
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=9a0a2ba2-4f1b-425d-979b-fe59192bb2cd@oss.qualcomm.com \
--to=mukesh.savaliya@oss.qualcomm.com \
--cc=Frank.Li@kernel.org \
--cc=agross@kernel.org \
--cc=andersson@kernel.org \
--cc=andi.shyti@kernel.org \
--cc=bartosz.golaszewski@oss.qualcomm.com \
--cc=bjorn.andersson@oss.qualcomm.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=dmaengine@vger.kernel.org \
--cc=dmitry.baryshkov@oss.qualcomm.com \
--cc=konrad.dybcio@oss.qualcomm.com \
--cc=konradybcio@kernel.org \
--cc=krzk+dt@kernel.org \
--cc=krzysztof.kozlowski@oss.qualcomm.com \
--cc=linmq006@gmail.com \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=quic_jseerapu@quicinc.com \
--cc=robh@kernel.org \
--cc=viken.dadhaniya@oss.qualcomm.com \
--cc=vkoul@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox