63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
/* SPDX-License-Identifier: GPL-2.0+ */
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/*
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 * Simple GPIO access from SPL. This only supports a single GPIO space,
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 * typically the SoC GPIO banks.
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 *
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 * Copyright 2018 Google LLC
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 */
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#ifndef __SPL_GPIO_H
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#define __SPL_GPIO_H
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#include <asm/gpio.h>
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/*
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 * The functions listed here should be implemented in the SoC GPIO driver.
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 * They correspond to the normal GPIO API (asm-generic/gpio.h). The GPIO
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 * number is encoded in an unsigned int by an SoC-specific means. Pull
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 * values are also SoC-specific.
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 *
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 * This API should only be used in TPL/SPL where GPIO access is needed but
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 * driver model is not available (yet) or adds too much overhead.
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 *
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 * The caller must supply the GPIO register base since this information is
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 * often specific to a particular SoC generation. This allows the GPIO
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 * code to be fairly generic.
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 *
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 * Only a single implementation of each of these functions can be provided.
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 *
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 * The 'gpio' value can include both a bank and a GPIO number, if desired. The
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 * encoding is SoC-specific.
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 */
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/**
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 * spl_gpio_set_pull() - Set the pull up/down state of a GPIO
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 *
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 * @regs: Pointer to GPIO registers
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 * @gpio: GPIO to adjust (SoC-specific)
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 * @pull: Pull value (SoC-specific)
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 * Return: return 0 if OK, -ve on error
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 */
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int spl_gpio_set_pull(void *regs, uint gpio, int pull);
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/**
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 * spl_gpio_output() - Set a GPIO as an output
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 *
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 * @regs: Pointer to GPIO registers
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 * @gpio: GPIO to adjust (SoC-specific)
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 * @value: 0 to set the output low, 1 to set it high
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 * Return: return 0 if OK, -ve on error
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 */
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int spl_gpio_output(void *regs, uint gpio, int value);
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/**
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 * spl_gpio_input() - Set a GPIO as an input
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 *
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 * @regs: Pointer to GPIO registers
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 * @gpio: GPIO to adjust (SoC-specific)
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 * Return: return 0 if OK, -ve on error
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 */
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int spl_gpio_input(void *regs, uint gpio);
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#endif /* __SPL_GPIO_H */
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