DART-SD410 Yocto GPIO
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DART-SD410 - Using GPIO
User LED4 (D15) connected to GPIO2 of the PMIC. The LED4 is not defined in the apq8016-var-dt410.dtsi file under gpio-leds section.
This allow user acces to this LED as GPIO device.
To change the state of the LED via serial console type:
# cd /sys/class/gpio # echo 509 > export This line creates a new directory gpio509 The number 509 calculated as 2 + 508. 2 is the GPIO number, 508 is static offset for PMIC gpio. So changing any other PMIC GPIO will lead to 508 + GPIO number. # cd gpio509 # echo out > direction # echo 1 > value The led will turn on #echo 0 > value The led will turn off
To read the current state type:
# cat value The output will be 0
You can change active state to active low.
# echo 1 > active_low # echo 0 > value The led is active low, writing 0 will turn on the led. # echo 1 > value The led is active low, writing 1 will turn off the led.
The Boot Select switch (SW3) connected to CPU GPIO81 the gpio offset for CPU is 0. to read its value use:
# cd /sys/class/gpio # echo 81 > export # cd gpio81 # cat value If the switch is in OFF position the output is 0. If the switch is in ON position the output is 1.
To see all allocated GPIOs in the system type:
# cat /sys/kernel/debug/gpio The output will be: GPIOs 0-121, platform/1000000.pinctrl, 1000000.pinctrl: gpio0 : in 2 16mA no pull gpio1 : in 2 16mA no pull gpio2 : in 2 16mA no pull gpio3 : in 2 16mA no pull gpio4 : out 2 16mA no pull gpio5 : out 2 16mA no pull gpio6 : in 0 2mA pull down gpio7 : in 0 2mA pull down gpio8 : in 1 12mA no pull gpio9 : in 1 12mA no pull gpio10 : out 0 2mA no pull gpio11 : in 1 12mA no pull gpio12 : out 0 2mA pull down gpio13 : in 0 2mA pull down gpio14 : in 2 16mA no pull gpio15 : in 2 16mA no pull gpio16 : in 1 12mA no pull gpio17 : in 1 12mA no pull gpio18 : out 0 2mA no pull gpio19 : in 1 12mA no pull gpio20 : in 0 2mA pull down gpio21 : out 0 16mA pull down gpio22 : in 2 16mA no pull gpio23 : in 2 16mA no pull gpio24 : in 0 2mA pull down gpio25 : in 0 2mA pull down gpio26 : in 0 2mA pull down gpio27 : in 1 16mA no pull gpio28 : out 0 16mA no pull gpio29 : in 1 16mA no pull gpio30 : in 1 16mA no pull gpio31 : in 0 2mA pull down gpio32 : out 0 16mA no pull gpio33 : out 0 16mA no pull gpio34 : in 0 2mA pull down gpio35 : in 0 2mA pull down gpio36 : in 0 2mA pull down gpio37 : in 0 2mA pull down gpio38 : in 0 2mA pull up gpio39 : in 0 2mA pull down gpio40 : in 1 6mA pull down gpio41 : in 1 6mA pull down gpio42 : in 1 6mA pull down gpio43 : in 1 6mA pull down gpio44 : in 1 6mA pull down gpio45 : in 0 2mA pull down gpio46 : in 0 2mA pull down gpio47 : in 0 2mA pull down gpio48 : in 0 2mA pull down gpio49 : in 0 2mA pull down gpio50 : in 0 2mA pull down gpio51 : in 0 2mA pull down gpio52 : in 0 2mA pull down gpio53 : in 0 2mA pull down gpio54 : in 0 2mA pull down gpio55 : in 0 2mA pull down gpio56 : in 0 2mA pull down gpio57 : in 0 2mA pull down gpio58 : in 0 2mA pull down gpio59 : in 0 2mA pull down gpio60 : in 0 2mA pull down gpio61 : in 0 2mA pull down gpio62 : in 0 2mA pull down gpio63 : in 1 8mA pull down gpio64 : in 1 8mA pull down gpio65 : in 1 8mA pull down gpio66 : in 1 8mA pull down gpio67 : in 1 8mA pull down gpio68 : in 1 8mA pull down gpio69 : in 0 2mA pull down gpio70 : in 0 2mA pull down gpio71 : in 0 2mA pull down gpio72 : in 0 2mA pull down gpio73 : in 0 2mA pull down gpio74 : in 0 2mA pull down gpio75 : in 0 2mA pull down gpio76 : in 0 2mA pull down gpio77 : in 0 2mA pull down gpio78 : in 0 2mA pull down gpio79 : in 0 2mA pull down gpio80 : in 0 2mA pull down gpio81 : in 0 2mA pull down gpio82 : in 0 2mA pull down gpio83 : in 0 2mA pull down gpio84 : in 0 2mA pull down gpio85 : in 0 2mA pull down gpio86 : in 0 2mA pull down gpio87 : in 0 2mA pull down gpio88 : in 0 2mA pull down gpio89 : in 0 2mA pull down gpio90 : in 0 2mA pull down gpio91 : in 0 2mA pull down gpio92 : in 0 2mA pull down gpio93 : in 0 2mA pull down gpio94 : in 0 2mA pull down gpio95 : in 0 2mA pull down gpio96 : out 0 2mA pull down gpio97 : in 0 2mA pull down gpio98 : in 0 2mA pull down gpio99 : in 0 2mA pull down gpio100 : in 0 2mA pull down gpio101 : in 0 2mA pull down gpio102 : in 0 2mA pull down gpio103 : in 0 2mA pull down gpio104 : in 0 2mA pull down gpio105 : in 0 2mA pull down gpio106 : in 0 2mA pull down gpio107 : in 0 8mA pull up gpio108 : in 0 2mA pull down gpio109 : in 0 2mA pull down gpio110 : in 0 2mA pull down gpio111 : in 0 2mA pull down gpio112 : in 1 8mA pull down gpio113 : in 0 2mA pull down gpio114 : in 0 2mA pull down gpio115 : in 0 2mA pull down gpio116 : in 1 8mA pull down gpio117 : in 1 8mA pull down gpio118 : in 1 8mA pull down gpio119 : in 1 8mA pull down gpio120 : out 0 16mA pull down gpio121 : in 0 8mA pull up GPIOs 504-507, platform/200f000.spmi:pm8916@0:mpps@a000, 200f000.spmi:pm8916@0:mpps@a000: mpp1 : out analog vin-2 0 0.6kOhm high mpp2 : out digital vin-0 0 0.6kOhm low mpp3 : out digital vin-0 0 0.6kOhm low mpp4 : out digital vin-3 0 0.6kOhm low GPIOs 508-511, platform/200f000.spmi:pm8916@0:gpios@c000, 200f000.spmi:pm8916@0:gpios@c000: gpio1 : out normal vin-0 pull-down 10uA push-pull low high gpio2 : out normal vin-0 pull-down 10uA push-pull low high gpio3 : out normal vin-0 pull-down 10uA push-pull high high gpio4 : out normal vin-0 pull-down 10uA push-pull low high
From this table you can see that offsets are:
- CPU gpio is 0
- PMIC gpio is 508
- PMIC mpp is 504