I am unable to turn off the LED's on the PINTO-TH board using the latest 3.0 sakoman image created with "sudo ./mksdcard.sh /dev/sdc overo gnome".
uname -a reveals "Linux omap3-multi 3.0.0 #1 Wed Dec 7 15:18:15 PST 2011 armv7l GNU/Linux"
I have tried to turn them off using "echo 0 > /sys/class/leds/overo\:red\:gpio21/brightness" and "echo 0 > /sys/class/leds/overo\:blue\:gpio22/brightness".
I have tried a second PINTO-TH board, and had the same results.
Is there something I need to enable in the kernel before I can control the LED's?
How do I enable setting output values or reading input values on all of the IO pins exposed on PINTO-TH/Thumbo boards? I have heard reference to modifying board-overo.c? in the kernel, but as yet have not gained an understanding of what is need to be done to enable all the IO lines.
My goal is to get as close as I can to "Enabling CPU_IDLE in the kernel build results in a reduction to 142mA @
5V (0.71 Watts), a quite impressive savings of 0.47 Watts!" from http://www.sakoman.com/OMAP/an-overiew-of-omap3-power-management-with-2639-pm.html
Running the overo Fire COM on a PINTO-TH board I am seeing minimum consumption levels of 5v @ 0.29A ( 1.45 Watts ) I suppose I could already be at the lowest levels given that I have the radio's on...
cpufrequtils 006: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to firstname.lastname@example.org, please.
analyzing CPU 0:
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 300 us.
hardware limits: 125 MHz - 720 MHz
available frequency steps: 125 MHz, 250 MHz, 500 MHz, 550 MHz, 600 MHz, 720 MHz
available cpufreq governors: conservative, ondemand, powersave, userspace, performance
current policy: frequency should be within 125 MHz and 720 MHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 125 MHz (asserted by call to hardware).
cpufreq stats: 125 MHz:0.39%, 250 MHz:0.00%, 500 MHz:99.61%, 550 MHz:0.00%, 600 MHz:0.00%, 720 MHz:0.00% (1)
The current kernel's configuration (zgrep'd /proc/config.gz for CPU, IDLE, or POWER)
# CONFIG_CPU_BPREDICT_DISABLE is not set
# CONFIG_CPU_DCACHE_DISABLE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
# CONFIG_CPU_ICACHE_DISABLE is not set
# CONFIG_DEBUG_FORCE_WEAK_PER_CPU is not set
# CONFIG_HID_LCPOWER is not set
# CONFIG_HID_WACOM_POWER_SUPPLY is not set
# CONFIG_PDA_POWER is not set
# CONFIG_POWER_SUPPLY_DEBUG is not set
# CONFIG_TEST_POWER is not set
# CPU Frequency scaling
# CPU Power Management
# on-CPU RTC drivers
Can anyone spot where I have gone wrong?