Messages in this thread | | | From | Bjorn Andersson <> | Date | Mon, 6 Nov 2017 10:11:13 -0800 | Subject | Re: [PATCH v5 0/7] PM / devfreq: Use OPP interface to handle the frequency |
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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).
Prior to this series the call to devm_devfreq_add_device() would return ok even though the ufshcd device does not come with a opp table. Afaict the code then relies on the devfreq code to target 0 and MAX_INT (see ufshcd_devfreq_target()), to switch between a "high" and "low" frequency.
I'm quite skeptical of the ufshcd code, so can you please confirm if this usage of the devfreq interface is valid or not?
PS. If I do register some frequencies (and hack up ufshcd_devfreq_target() accordingly) this works again, but the "high" and "low" currently affects two clocks with different frequencies, so I'm not sure how to properly describe the two clocks frequencies. Should I just map "high"/"low" of the primary clock to "high"/"low" frequencies of the secondary clock?
Regards, Bjorn
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