linux-kernel - Re: [PATCH v4 1/7] clk: msm8996-gcc: change halt check for USB/PCIE pipe

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Date:   Thu, 29 Mar 2018 13:55:55 -0700
From:   Doug Anderson <dianders@...omium.org>
To:     Manu Gautam <mgautam@...eaurora.org>
Cc:     Kishon Vijay Abraham I <kishon@...com>,
        Rob Herring <robh@...nel.org>,
        Stephen Boyd <sboyd@...eaurora.org>,
        LKML <linux-kernel@...r.kernel.org>, devicetree@...r.kernel.org,
        Rob Herring <robh+dt@...nel.org>,
        Vivek Gautam <vivek.gautam@...eaurora.org>,
        Evan Green <evgreen@...omium.org>,
        linux-arm-msm@...r.kernel.org, Andy Gross <andy.gross@...aro.org>,
        David Brown <david.brown@...aro.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        "open list:ARM/QUALCOMM SUPPORT" <linux-soc@...r.kernel.org>,
        "open list:COMMON CLK FRAMEWORK" <linux-clk@...r.kernel.org>
Subject: Re: [PATCH v4 1/7] clk: msm8996-gcc: change halt check for USB/PCIE pipe_clk

Hi,

On Thu, Mar 29, 2018 at 4:04 AM, Manu Gautam <mgautam@...eaurora.org> wrote:
> The USB and PCIE pipe clocks are sourced from external clocks
> inside the QMP USB/PCIE PHYs. Enabling or disabling of PIPE RCG
> clocks is dependent on PHY initialization sequence hence
> update halt_check to BRANCH_HALT_DELAY for these clocks so
> that clock status bit is not polled when enabling or disabling
> the clocks. It allows to simplify PHY client driver code which
> is both user and source of the pipe_clk and avoid error logging
> related status check on clk_disable/enable.
>
> Signed-off-by: Manu Gautam <mgautam@...eaurora.org>
> ---
>  drivers/clk/qcom/gcc-msm8996.c | 4 ++++
>  1 file changed, 4 insertions(+)

As per my feedback on <https://patchwork.kernel.org/patch/10314937/>,
I'm not a fan of this.  Hopefully we can adjust the PHY driver so it's
not needed.

-Doug