28 lines
		
	
	
		
			666 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			28 lines
		
	
	
		
			666 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
What:		/dev/gpiochip[0-9]+
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Date:		November 2015
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KernelVersion:	4.4
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Contact:	linux-gpio@vger.kernel.org
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Description:
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		The character device files /dev/gpiochip* are the interface
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		between GPIO chips and userspace.
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		The ioctl(2)-based ABI is defined and documented in
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		[include/uapi]<linux/gpio.h>.
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		The following file operations are supported:
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		open(2)
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		  Currently the only useful flags are O_RDWR.
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		ioctl(2)
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		  Initiate various actions.
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		  See the inline documentation in [include/uapi]<linux/gpio.h>
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		  for descriptions of all ioctls.
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		close(2)
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		  Stops and free up the I/O contexts that was associated
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		  with the file descriptor.
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Users:		TBD
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