linux-kernel - Re: [PATCH V7 5/5] arm64: dts: qcom: sc7280: Add pm8008 support for sc7280-idp

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: <7e3d1ff3-f1a0-3a4d-a056-e3dce1a9a28d@quicinc.com>
Date:   Mon, 7 Mar 2022 20:19:31 +0530
From:   "Satya Priya Kakitapalli (Temp)" <quic_c_skakit@...cinc.com>
To:     Stephen Boyd <swboyd@...omium.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Rob Herring <robh+dt@...nel.org>
CC:     Lee Jones <lee.jones@...aro.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>,
        Das Srinagesh <gurus@...eaurora.org>,
        <linux-arm-msm@...r.kernel.org>, <devicetree@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>, <quic_collinsd@...cinc.com>,
        <quic_subbaram@...cinc.com>, <quic_jprakash@...cinc.com>
Subject: Re: [PATCH V7 5/5] arm64: dts: qcom: sc7280: Add pm8008 support for
 sc7280-idp


On 3/1/2022 2:06 AM, Stephen Boyd wrote:
> Quoting Satya Priya Kakitapalli (Temp) (2022-02-28 06:25:06)
>> On 2/19/2022 7:31 AM, Stephen Boyd wrote:
>>> Quoting Satya Priya (2022-02-18 03:01:03)
>>>> +               pins = "gpio4";
>>>> +               function = "normal";
>>>> +               bias-disable;
>>>> +               output-high;
>>> Is this a reset signal? Should the driver be deasserting the reset when
>>> it is ready? That could be the same time the gpio is acquired.
>>
>> I didn't get your question exactly.. hope this answers your query
>>
>> The pm8008 chip needs this gpio to be toggled , in order to come out of
>> reset and start any transactions..
>>
>> Please let me know if you have more queries
> Yes that answers it for me. Thanks.
>
> This is a reset gpio and should be a DT property like
>
> 	reset-gpios = <&pm8350c_gpios 4 GPIO_ACTIVE_HIGH>
>
> in the pm8008 node. When the driver probes it should get the gpio and
> do any toggling to take it out of reset. It shouldn't be done through
> pinconf settings.


Okay, IIUC,  I have to remove the output-high here and add reset-gpios 
in pm8008 DT node. And then add below code in pm8008 mfd driver probe

+               chip->reset_gpio = devm_gpiod_get(chip->dev, "reset", 
GPIOD_OUT_HIGH);
+               if (IS_ERR(chip->reset_gpio)) {
+                       dev_err(chip->dev, "failed to acquire reset 
gpio\n");
+                       return PTR_ERR(chip->reset_gpio);
+               }
+               gpiod_set_value(chip->reset_gpio, 1);

This is working for me, Please let me know if I'm  missing something.