You need root access to change cpufreq values. I'm not sure if this is available on the Google IO devices but try:
adb root to switch into root mode, or adb su <foo> userspace is not compiled into the kernel for the ADP2, you will need to either compile a custom kernel, or just pin the min/max speeds to the speed you wish to set. -- Mike On Tue, Mar 23, 2010 at 1:16 PM, ecss utdallas <dianyuangua...@gmail.com> wrote: > Firstly, many thanks for your answer. That really helps a lot. I am using > the ADP2 actually a google IO phone. When I did "adb shell cat > /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governor". The result > is : "ondemand, performance". It means that the sytem on my phone only > supports ondemand and performance scaling governors. Also when I try to use > "adb shell echo userspace > /sys/devices/.../scaling_governor", it always > shows the problem that " Permission denied". Did you face similar problem > when enable userspace governor? Would you please give me some advice on how > to solve these problems? I will appreciate very very much for your help. > > On Mon, Mar 22, 2010 at 1:42 PM, Mike Chan <m...@android.com> wrote: >> >> What phone did you buy? If you're talking about the Nexus One the >> userspace governor is already compiled into the kernel. Otherwise >> you'll probably have to recompile the kernel with the userspace >> governor. >> >> We do DVFS using the ondemand governor currently. >> >> To enable userspace governor: >> adb shell echo "userspace > >> /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor" >> >> To set the speed: >> >> adb shell echo "xxx > >> /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq" >> >> -- Mike >> >> >> >> On Sun, Mar 21, 2010 at 11:28 PM, xlshe <dianyuangua...@gmail.com> wrote: >> > I have bought the android develop phone 2. I want to do some research >> > about >> > power management on ADP2. But I wonder if ADP2 support Dynamic Voltage >> > and >> > Frequency Scaling(DVFS). That means whether we can change the CPU >> > frequency >> > dynamically on ADP2. Previously, someone told me that I can rebuild >> > the >> > android OS kernel and turn on the user space and then I can set the >> > CPU >> > frequency. I have tried to rebuild the kernel just as " >> > http://source.android.com/documentation/building-for-dream"; said. But >> > I >> > still don't know how to turn on the user space when built the kernel >> > and >> > don't know how to set the CPU frequency on ADP2. Would you kindly give >> > me >> > some support on how to dynamically set the CPU frequency on ADP2? I >> > will >> > appreciate very very much for your support. >> > >> > -- >> > unsubscribe: android-kernel+unsubscr...@googlegroups.com >> > website: http://groups.google.com/group/android-kernel >> > >> > To unsubscribe from this group, send email to >> > android-kernel+unsubscribegooglegroups.com or reply to this email with the >> > words "REMOVE ME" as the subject. >> > >> >> -- >> unsubscribe: android-kernel+unsubscr...@googlegroups.com >> website: http://groups.google.com/group/android-kernel >> >> To unsubscribe from this group, send email to >> android-kernel+unsubscribegooglegroups.com or reply to this email with the >> words "REMOVE ME" as the subject. > > -- > unsubscribe: android-kernel+unsubscr...@googlegroups.com > website: http://groups.google.com/group/android-kernel > > To unsubscribe from this group, send email to > android-kernel+unsubscribegooglegroups.com or reply to this email with the > words "REMOVE ME" as the subject. > -- unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel To unsubscribe from this group, send email to android-kernel+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.
