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Date: Thu, 9 Nov 2017 16:12:59 -0800
From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Chanwoo Choi <cw00.choi@samsung.com>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        "rafael.j.wysocki@intel.com" <rafael.j.wysocki@intel.com>,
        "chanwoo@kernel.org" <chanwoo@kernel.org>,
        Inki Dae <inki.dae@samsung.com>, lkml <linux-kernel@vger.kernel.org>,
        Linux PM list <linux-pm@vger.kernel.org>,
        Vinayak Holikatti <vinholikatti@gmail.com>,
        Vivek Gautam <vivek.gautam@codeaurora.org>
Subject: Re: [PATCH v5 0/7] PM / devfreq: Use OPP interface to handle the
 frequency
Message-ID: <20171110001259.GD28761@minitux>
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On Thu 09 Nov 15:56 PST 2017, MyungJoo Ham wrote:

> > On Sun, Oct 22, 2017 at 6:32 PM, Chanwoo Choi <cw00.choi@samsung.com> wrote:
> > > These patches makes the devfreq to use the OPP interface and clean-up codes.
> > >
> >
> > Hi Chanwoo,
> >
> > This patch series breaks UFS support on modern Qualcomm platforms
> > (e.g. MSM8996).
> 
> Could you please show us the code location of it? 
> 

The driver is drivers/scsi/ufs/ufshcd.c function ufshcd_probe_hba()
calls devm_devfreq_add_device() without there being an opp table
associated with hba->dev. This used to return fine and
ufshcd_devfreq_target() was called with *freq = UINT_MAX.

Unfortunately the driver seems to be designed in such a way that without
a call to ufshcd_devfreq_target() with *freq 0 or UINT_MAX some clock is
left off, causing my board to reboot; so there's unfortunately a few
levels of issues to fix here.

Regards,
Bjorn