Commit 689f2a01 authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Russell King

[ARM] 4590/1: ns9xxx: add gpio handling functions

This implementation conforms to the general GPIO API
introduced in 2.6.21.

This patch was signed-of by David Brownell before I exported the functions
using EXPORT_SYMBOL.
Signed-off-by: default avatarUwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent ba7d850a
......@@ -318,6 +318,7 @@ config ARCH_KS8695
config ARCH_NS9XXX
bool "NetSilicon NS9xxx"
select GENERIC_GPIO
help
Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
System.
......
obj-y := irq.o time.o generic.o
obj-y := irq.o time.o generic.o gpio.o
obj-$(CONFIG_MACH_CC9P9360DEV) += mach-cc9p9360dev.o
obj-$(CONFIG_MACH_CC9P9360JS) += mach-cc9p9360js.o
......
/*
* arch/arm/mach-ns9xxx/gpio.c
*
* Copyright (C) 2006 by Digi International Inc.
* All rights reserved.
*
* 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/compiler.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <asm/arch-ns9xxx/gpio.h>
#include <asm/arch-ns9xxx/processor.h>
#include <asm/arch-ns9xxx/regs-bbu.h>
#include <asm/bug.h>
#include <asm/types.h>
#include <asm/bitops.h>
#if defined(CONFIG_PROCESSOR_NS9360)
#define GPIO_MAX 72
#elif defined(CONFIG_PROCESSOR_NS9750)
#define GPIO_MAX 49
#endif
/* protects BBU_GCONFx and BBU_GCTRLx */
static spinlock_t gpio_lock = __SPIN_LOCK_UNLOCKED(gpio_lock);
/* only access gpiores with atomic ops */
static DECLARE_BITMAP(gpiores, GPIO_MAX);
static inline int ns9xxx_valid_gpio(unsigned gpio)
{
#if defined(CONFIG_PROCESSOR_NS9360)
if (processor_is_ns9360())
return gpio <= 72;
else
#endif
#if defined(CONFIG_PROCESSOR_NS9750)
if (processor_is_ns9750())
return gpio <= 49;
else
#endif
BUG();
}
static inline volatile u32 *ns9xxx_gpio_get_gconfaddr(unsigned gpio)
{
if (gpio < 56)
return &BBU_GCONFb1(gpio / 8);
else
/*
* this could be optimised away on
* ns9750 only builds, but it isn't ...
*/
return &BBU_GCONFb2((gpio - 56) / 8);
}
static inline volatile u32 *ns9xxx_gpio_get_gctrladdr(unsigned gpio)
{
if (gpio < 32)
return &BBU_GCTRL1;
else if (gpio < 64)
return &BBU_GCTRL2;
else
/* this could be optimised away on ns9750 only builds */
return &BBU_GCTRL3;
}
static inline volatile u32 *ns9xxx_gpio_get_gstataddr(unsigned gpio)
{
if (gpio < 32)
return &BBU_GSTAT1;
else if (gpio < 64)
return &BBU_GSTAT2;
else
/* this could be optimised away on ns9750 only builds */
return &BBU_GSTAT3;
}
int gpio_request(unsigned gpio, const char *label)
{
if (likely(ns9xxx_valid_gpio(gpio)))
return test_and_set_bit(gpio, gpiores) ? -EBUSY : 0;
else
return -EINVAL;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned gpio)
{
clear_bit(gpio, gpiores);
return;
}
EXPORT_SYMBOL(gpio_free);
/*
* each gpio can serve for 4 different purposes [0..3]. These are called
* "functions" and passed in the parameter func. Functions 0-2 are always some
* special things, function 3 is GPIO. If func == 3 dir specifies input or
* output, and with inv you can enable an inverter (independent of func).
*/
static int __ns9xxx_gpio_configure(unsigned gpio, int dir, int inv, int func)
{
volatile u32 *conf = ns9xxx_gpio_get_gconfaddr(gpio);
u32 confval;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
confval = *conf;
REGSETIM_IDX(confval, BBU_GCONFx, DIR, gpio & 7, dir);
REGSETIM_IDX(confval, BBU_GCONFx, INV, gpio & 7, inv);
REGSETIM_IDX(confval, BBU_GCONFx, FUNC, gpio & 7, func);
*conf = confval;
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
int ns9xxx_gpio_configure(unsigned gpio, int inv, int func)
{
if (likely(ns9xxx_valid_gpio(gpio))) {
if (func == 3) {
printk(KERN_WARNING "use gpio_direction_input "
"or gpio_direction_output\n");
return -EINVAL;
} else
return __ns9xxx_gpio_configure(gpio, 0, inv, func);
} else
return -EINVAL;
}
EXPORT_SYMBOL(ns9xxx_gpio_configure);
int gpio_direction_input(unsigned gpio)
{
if (likely(ns9xxx_valid_gpio(gpio))) {
return __ns9xxx_gpio_configure(gpio, 0, 0, 3);
} else
return -EINVAL;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned gpio, int value)
{
if (likely(ns9xxx_valid_gpio(gpio))) {
gpio_set_value(gpio, value);
return __ns9xxx_gpio_configure(gpio, 1, 0, 3);
} else
return -EINVAL;
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_get_value(unsigned gpio)
{
volatile u32 *stat = ns9xxx_gpio_get_gstataddr(gpio);
int ret;
ret = 1 & (*stat >> (gpio & 31));
return ret;
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned gpio, int value)
{
volatile u32 *ctrl = ns9xxx_gpio_get_gctrladdr(gpio);
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
if (value)
*ctrl |= 1 << (gpio & 31);
else
*ctrl &= ~(1 << (gpio & 31));
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(gpio_set_value);
/*
* include/asm-arm/arch-ns9xxx/gpio.h
*
* Copyright (C) 2007 by Digi International Inc.
* All rights reserved.
*
* 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.
*/
#ifndef __ASM_ARCH_GPIO_H
#define __ASM_ARCH_GPIO_H
#include <asm/errno.h>
int gpio_request(unsigned gpio, const char *label);
void gpio_free(unsigned gpio);
int ns9xxx_gpio_configure(unsigned gpio, int inv, int func);
int gpio_direction_input(unsigned gpio);
int gpio_direction_output(unsigned gpio, int value);
int gpio_get_value(unsigned gpio);
void gpio_set_value(unsigned gpio, int value);
/*
* ns9xxx can use gpio pins to trigger an irq, but it's not generic
* enough to be supported by the gpio_to_irq/irq_to_gpio interface
*/
static inline int gpio_to_irq(unsigned gpio)
{
return -EINVAL;
}
static inline int irq_to_gpio(unsigned irq)
{
return -EINVAL;
}
/* get the cansleep() stubs */
#include <asm-generic/gpio.h>
#endif /* ifndef __ASM_ARCH_GPIO_H */
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