29 lines
		
	
	
		
			705 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			29 lines
		
	
	
		
			705 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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| 
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| 		The ioctl(2)-based ABI is defined in
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| 		[include/uapi]<linux/gpio.h> and documented in
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| 		Documentation/userspace-api/gpio/chardev.rst.
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| 
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| 		The following file operations are supported:
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| 
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| 		open(2)
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| 		  Currently the only useful flags are O_RDWR.
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| 
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| 		ioctl(2)
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| 		  Initiate various actions.
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| 
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| 		  See Documentation/userspace-api/gpio/chardev.rst
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| 		  for a description of all ioctls.
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| 
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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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| 
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| Users:		TBD
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