Part Number: AM3354
Tool/software: Linux
DTS file:
gpio_pins: gpio_pins{
pinctrl-single,pins = <
0x158 (PIN_INPUT_PULLDOWN | MUX_MODE2) /*(B16) spi0_d1.i2c1_sda */
0x150 ( PIN_INPUT_PULLDOWN | MUX_MODE7 ) /*(A17) spi0_sclk.gpio0[2]*/
0x154 ( PIN_INPUT_PULLDOWN | MUX_MODE7 ) /*(B17) spi0_d0.gpio0[3] */
>;
};
After loading the dtb file on the board able to see the grouped gpio pins as below
# cat /sys/kernel/debug/pinctrl/44e10880..*/pingroups
group: pinmux_gpio_pins
pin 86 (PIN86)
pin 84 (PIN84)
pin 85 (PIN85)
When we export the 86, 84 and 85 pins and tried to read the gpio pins are giving status 0 every time. Even the pins are changed to High and Low.
#echo '84' > /sys/class/gpio/export
#echo '85' > /sys/class/gpio/export
#echo '86' > /sys/class/gpio/export
#echo "in" > /sys/class/gpio/gpio84/direction
#echo "in" > /sys/class/gpio/gpio85/direction
#echo "in" > /sys/class/gpio/gpio86/direction
Default:
#echo "Gpio-84: "`cat /sys/class/gpio/gpio84/value`
Gpio-84: 0
#echo "Gpio-85: "`cat /sys/class/gpio/gpio85/value`
Gpio-85: 0
#echo "Gpio-86: "`cat /sys/class/gpio/gpio86/value`
Gpio-86: 0
After pull up:
#echo "Gpio-84: "`cat /sys/class/gpio/gpio84/value`
Gpio-84: 0
#echo "Gpio-85: "`cat /sys/class/gpio/gpio85/value`
Gpio-85: 0
#echo "Gpio-86: "`cat /sys/class/gpio/gpio86/value`
Gpio-86: 0
Please help to solve this issue.
Thanks in advance!
