Hi all,
I am currently using SDK 7.00 for am335x custom board, I am trying to read the value of an input. I am using kernel 3.12 kernel. The only way I have found is to manually export the gpio and then read the value but i want read gpio buttons through sys. here i am using pre defined gpio drive gpio_keys.c. find the device tree bellow... gpio_keys_s0: gpio_keys_s0 { pinctrl-single,pins = < 0x2c (PIN_INPUT_PULLUP | MUX_MODE7) /*key_init GPIO0_27 */ 0x20 (PIN_INPUT_PULLUP | MUX_MODE7) /* Alaram_key GPIO0_22 */ 0x28 (PIN_INPUT_PULLUP | MUX_MODE7) /* Cancel_key GPIO0_26---- 0x28 */ 0x24 (PIN_INPUT_PULLUP | MUX_MODE7) /* Away_key GPIO0_23 */ >; }; gpio_buttons: gpio_buttons@0 { compatible = "gpio-keys"; pinctrl-names = "default"; pinctrl-0 = <&gpio_keys_s0>; #address-cells = <1>; #size-cells = <0>; switch@1 { label = "key_init"; debounce_interval = <50>; linux,code = <100>; gpios = <&gpio0 27 GPIO_ACTIVE_HIGH>; gpio-key,wakeup; }; switch@2 { label = "Alaram_key"; linux,code = <0x102>; gpios = <&gpio0 22 GPIO_ACTIVE_HIGH>; }; switch@3 { label = "Cancel_key"; linux,code = <0x103>; gpios = <&gpio0 26 GPIO_ACTIVE_HIGH>; gpio-key,wakeup; }; switch@4 { label = "Away_key"; linux,code = <0x108>; gpios = <&gpio0 23 GPIO_ACTIVE_HIGH>; }; }; I can see the the events occur in /dev/input/event0. root@am335x-evm:/dev/input# cat event1 ▒Dm8▒R ▒Dm8▒R ▒Dm8'S ▒Dm8'S ▒Dm8= The problem is I need to read the value and not trigger off of an interrupt. but i want read the value through sys file like leds output root@am335x-evm:/sys/class/leds/beaglebone:green:usr3# root@am335x-evm:/sys/class/leds/beaglebone:green:usr3# echo 1 >brightness root@am335x-evm:/sys/class/leds/beaglebone:green:usr3# cat brightness 1 please help me how to read input gpio data as well as how to export gpio buttons attributes to sys directory Thankas & Regards shankar -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.