4,199
edits
Changes
From IGEP - ISEE Wiki
no edit summary
===== First way: =====
This mode has a issue, when your system reboot or shutdown you will need to configure again. Using user space to configure mux and powerdown TFP410. Logging with root user via SSH or Serial cable.<br> NOTE: Poky distribution does not have debug filesystem enabled. Mount it: <pre>mount -t debugfs none /sys/kernel/debug</pre> Go to /sys/kernel/debug/omap_mux/<br> Set hdq_sio to gpio170 (mode 4): <pre>echo 0x104 > hdp_sio</pre> Revise that: <pre>root@localhost:/sys/kernel/debug/omap_mux# cat hdq_sio name: hdq_sio.gpio_170 (0x480021c6/0x196 = 0x0104), b j25, t NAmode: OMAP_PIN_INPUT | OMAP_MUX_MODE4signals: hdq_sio | sys_altclk | i2c2_sccbe | i2c3_sccbe | gpio_170 | NA | NA | safe_moderoot@localhost:/sys/kernel/debug/omap_mux# </pre> Go to: /sys/class/gpio/ Check that gpio170 is in user space: <pre>root@localhost:/sys/class/gpio# lsexport gpio137 gpio138 gpio139 gpio170 gpio64 gpiochip0 gpiochip128 gpiochip160 gpiochip192 gpiochip32 gpiochip64 gpiochip96 unexportroot@localhost:/sys/class/gpio# </pre> If you don't have it, you should export gpio170: <br> <pre>echo 170 > /sys/class/gpio/export </pre> Set gpio170 to low value to disable TFP410: <pre>echo 0 > /sys/class/gpio/gpio170/value</pre> Revise that: <pre>root@localhost:/sys/class/gpio# cat /sys/class/gpio/gpio170/value 0root@localhost:/sys/class/gpio# </pre> It was tested using alternate peripherals like UARTs and GPIOs.<br>
=====Second way:=====