What is Sysfs interface?

sysfs is a pseudo file system provided by the Linux kernel that exports information about various kernel subsystems, hardware devices, and associated device drivers from the kernel’s device model to user space through virtual files.

How do I Unexport my GPIO pin?

To export a pin, we write the pin name/number to the pseudo file /sys/class/gpio/export….Basic Steps

  1. Export the pin.
  2. Set the pin direction (input or output).
  3. If an output pin, set the level to low or high.
  4. If an input pin, read the pin’s level (low or high).
  5. When done, unexport the pin.

How do I find my GPIO pin number?

The Linux GPIO number for a certain GPIO pin can be determined by adding the GPIO pin index to the port base index. For instance: i. MX6 GPIO2_4 (port 2, pin 4) is: 32 + 4 = 36.

What is sysfs and Procfs?

proc and sysfs are two pseudo filesystems that give a window onto the inner workings of the kernel. They both represent kernel data as files in a hierarchy of directories: when you read one of the files, the contents you see do not come from disk storage, it has been formatted on-the-fly by a function in the kernel.

Is sysfs a system call?

The (obsolete) sysfs() system call returns information about the filesystem types currently present in the kernel.

Why is Sysfs deprecated?

Since linux 4.8 the GPIO sysfs interface is deprecated. Due to its many drawbacks and bad design decisions a new user space interface has been implemented in the form of the GPIO character device which is now the preferred method of interaction with GPIOs which can’t otherwise be serviced by a kernel driver.

What is GPIO configuration?

A GPIO port is a platform-defined grouping of GPIO pins that can be configured for output or input. Like GPIO pins, each GPIO port is identified by a numerical ID and by a name.