Touchscreen failure with CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND

[Fabio Estevam]

Hi Viresh,

On Mon, Apr 24, 2017 at 1:07 AM, Viresh Kumar <viresh.kumar at linaro.org> wrote:

> So as Rafael pointed out the problem doesn't happen if you stay at the max
> frequencies, but otherwise.
>
> You need to investigate on why that is the case. You can go to the cpufreq sysfs
> directory and see what frequencies are getting selected, etc..

Yes, when the CPU frequency stays at 996 MHz I do not see the
touchscreen failure. When it goes to 396MHz I do see see touchscreeen
events getting lost.

> Give me output of this for now:
>
> grep . /sys/devices/system/cpu/cpufreq/policy0/*
> grep . /sys/devices/system/cpu/cpufreq/policy0/stats/*

Here it goes, thanks.

# grep . /sys/devices/system/cpu/cpufreq/policy0/*
/sys/devices/system/cpu/cpufreq/policy0/affected_cpus:0 1 2 3
/sys/devices/system/cpu/cpufreq/policy0/cpuinfo_cur_freq:396000
/sys/devices/system/cpu/cpufreq/policy0/cpuinfo_max_freq:996000
/sys/devices/system/cpu/cpufreq/policy0/cpuinfo_min_freq:396000
/sys/devices/system/cpu/cpufreq/policy0/cpuinfo_transition_latency:109036
/sys/devices/system/cpu/cpufreq/policy0/related_cpus:0 1 2 3
/sys/devices/system/cpu/cpufreq/policy0/scaling_available_frequencies:396000
792000 996000
/sys/devices/system/cpu/cpufreq/policy0/scaling_available_governors:ondemand
performance
/sys/devices/system/cpu/cpufreq/policy0/scaling_cur_freq:396000
/sys/devices/system/cpu/cpufreq/policy0/scaling_driver:imx6q-cpufreq
/sys/devices/system/cpu/cpufreq/policy0/scaling_governor:ondemand
/sys/devices/system/cpu/cpufreq/policy0/scaling_max_freq:996000
/sys/devices/system/cpu/cpufreq/policy0/scaling_min_freq:396000
/sys/devices/system/cpu/cpufreq/policy0/scaling_setspeed:<unsupported>

# grep . /sys/devices/system/cpu/cpufreq/policy0/stats/*
grep: /sys/devices/system/cpu/cpufreq/policy0/stats/reset: Permission denied
/sys/devices/system/cpu/cpufreq/policy0/stats/time_in_state:396000 2869
/sys/devices/system/cpu/cpufreq/policy0/stats/time_in_state:792000 76
/sys/devices/system/cpu/cpufreq/policy0/stats/time_in_state:996000 33
/sys/devices/system/cpu/cpufreq/policy0/stats/total_trans:8
/sys/devices/system/cpu/cpufreq/policy0/stats/trans_table:   From  :    To
/sys/devices/system/cpu/cpufreq/policy0/stats/trans_table:         :
 396000    792000    996000
/sys/devices/system/cpu/cpufreq/policy0/stats/trans_table:   396000:
      0         2         0
/sys/devices/system/cpu/cpufreq/policy0/stats/trans_table:   792000:
      2         0         2
/sys/devices/system/cpu/cpufreq/policy0/stats/trans_table:   996000:
      1         1         0