I'm using a commercial board based on the LS1021A SoC which is running Linux.
I would like to test the GPIO's functionality by configuring it as output and probing the signal.
From userspace Linux I would like to export a gpio port and use the sysfs gpio files to manipulate the port. But to do that I need to know what each gpio<number> represents.
This is the port mapping as provided by debugfs:
~ cat /sys/kernel/debug/gpio
GPIOs 358-359, i2c/0-0060, gpio-pca9532, can sleep:
gpio-358 ( |backlight ) out lo
GPIOs 360-367, platform/stmpe-gpio, stmpe, can sleep:
gpio-360 ((none) ) in lo edge-inactive
gpio-361 ((none) ) in lo edge-inactive
gpio-362 ((none) ) in lo edge-inactive
gpio-363 ((none) ) in lo edge-inactive
gpio-364 ((none) ) in lo edge-inactive
gpio-365 ((none) ) in lo edge-inactive
gpio-366 ((none) ) in lo edge-inactive
gpio-367 ((none) ) in lo edge-inactive
GPIOs 368-375, i2c/0-0021, pca9554, can sleep:
GPIOs 376-383, i2c/0-0020, pca9554, can sleep:
GPIOs 384-415, /soc/gpio@2330000:
GPIOs 416-447, /soc/gpio@2320000:
GPIOs 448-479, /soc/gpio@2310000:
GPIOs 480-511, /soc/gpio@2300000:
According to this mapping GPIO1 is assigned the numbers from 480 to 511.
Is GPIO1_13 == 480 , GPIO1_14 == 481 ....and so on?
Same question for the rest of the ports
GPIO2_4 == 448 , GPIO2_5 == 449
GPIO3_0 == 416, GPIO3_1 == 417
Can you please confirm that this mapping is correct?
Thanks
Solved! Go to Solution.
The GPIO1_13 is 480+13= 493.
The GPIO2_4 is 448+4=452
The GPIO3_0 == 416, GPIO3_1 == 417
Look at the following pages:
https://www.kernel.org/doc/Documentation/gpio/sysfs.txt
CI20_GPIO_LED_Blink_Tutorial
http://falsinsoft.blogspot.ru/2012/11/access-gpio-from-linux-user-space.html
https://wiki.openwrt.org/doc/hardware/port.gpio
Have a great day,
Pavel Chubakov
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The GPIO1_13 is 480+13= 493.
The GPIO2_4 is 448+4=452
The GPIO3_0 == 416, GPIO3_1 == 417
Look at the following pages:
https://www.kernel.org/doc/Documentation/gpio/sysfs.txt
CI20_GPIO_LED_Blink_Tutorial
http://falsinsoft.blogspot.ru/2012/11/access-gpio-from-linux-user-space.html
https://wiki.openwrt.org/doc/hardware/port.gpio
Have a great day,
Pavel Chubakov
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
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