TXx9 GPIO set/get routines are spinlock-safe.  This patch make
gpio_direction_{input,output} routines also spinlock-safe so that they
can be used during early board setup.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
		
	
			
		
			
				
	
	
		
			89 lines
		
	
	
	
		
			2.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			89 lines
		
	
	
	
		
			2.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * A gpio chip driver for TXx9 SoCs
 | |
|  *
 | |
|  * Copyright (C) 2008 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
 | |
|  *
 | |
|  * This program is free software; you can redistribute it and/or modify
 | |
|  * it under the terms of the GNU General Public License version 2 as
 | |
|  * published by the Free Software Foundation.
 | |
|  */
 | |
| 
 | |
| #include <linux/init.h>
 | |
| #include <linux/spinlock.h>
 | |
| #include <linux/gpio.h>
 | |
| #include <linux/errno.h>
 | |
| #include <linux/io.h>
 | |
| #include <asm/txx9pio.h>
 | |
| 
 | |
| static DEFINE_SPINLOCK(txx9_gpio_lock);
 | |
| 
 | |
| static struct txx9_pio_reg __iomem *txx9_pioptr;
 | |
| 
 | |
| static int txx9_gpio_get(struct gpio_chip *chip, unsigned int offset)
 | |
| {
 | |
| 	return __raw_readl(&txx9_pioptr->din) & (1 << offset);
 | |
| }
 | |
| 
 | |
| static void txx9_gpio_set_raw(unsigned int offset, int value)
 | |
| {
 | |
| 	u32 val;
 | |
| 	val = __raw_readl(&txx9_pioptr->dout);
 | |
| 	if (value)
 | |
| 		val |= 1 << offset;
 | |
| 	else
 | |
| 		val &= ~(1 << offset);
 | |
| 	__raw_writel(val, &txx9_pioptr->dout);
 | |
| }
 | |
| 
 | |
| static void txx9_gpio_set(struct gpio_chip *chip, unsigned int offset,
 | |
| 			  int value)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 	spin_lock_irqsave(&txx9_gpio_lock, flags);
 | |
| 	txx9_gpio_set_raw(offset, value);
 | |
| 	mmiowb();
 | |
| 	spin_unlock_irqrestore(&txx9_gpio_lock, flags);
 | |
| }
 | |
| 
 | |
| static int txx9_gpio_dir_in(struct gpio_chip *chip, unsigned int offset)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 	spin_lock_irqsave(&txx9_gpio_lock, flags);
 | |
| 	__raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset),
 | |
| 		     &txx9_pioptr->dir);
 | |
| 	mmiowb();
 | |
| 	spin_unlock_irqrestore(&txx9_gpio_lock, flags);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int txx9_gpio_dir_out(struct gpio_chip *chip, unsigned int offset,
 | |
| 			     int value)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 	spin_lock_irqsave(&txx9_gpio_lock, flags);
 | |
| 	txx9_gpio_set_raw(offset, value);
 | |
| 	__raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset),
 | |
| 		     &txx9_pioptr->dir);
 | |
| 	mmiowb();
 | |
| 	spin_unlock_irqrestore(&txx9_gpio_lock, flags);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static struct gpio_chip txx9_gpio_chip = {
 | |
| 	.get = txx9_gpio_get,
 | |
| 	.set = txx9_gpio_set,
 | |
| 	.direction_input = txx9_gpio_dir_in,
 | |
| 	.direction_output = txx9_gpio_dir_out,
 | |
| 	.label = "TXx9",
 | |
| };
 | |
| 
 | |
| int __init txx9_gpio_init(unsigned long baseaddr,
 | |
| 			  unsigned int base, unsigned int num)
 | |
| {
 | |
| 	txx9_pioptr = ioremap(baseaddr, sizeof(struct txx9_pio_reg));
 | |
| 	if (!txx9_pioptr)
 | |
| 		return -ENODEV;
 | |
| 	txx9_gpio_chip.base = base;
 | |
| 	txx9_gpio_chip.ngpio = num;
 | |
| 	return gpiochip_add(&txx9_gpio_chip);
 | |
| }
 |