Re: [PATCH v5 0/7] PM / devfreq: Use OPP interface to handle the frequency

From: Bjorn Andersson
Date: Thu Nov 09 2017 - 19:13:12 EST


On Thu 09 Nov 15:56 PST 2017, MyungJoo Ham wrote:

> > On Sun, Oct 22, 2017 at 6:32 PM, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> 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