openwrt/target/linux/atheros/files/arch/mips/atheros/gpio.c

340 lines
9.8 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2003 Atheros Communications, Inc., All Rights Reserved.
* Copyright (C) 2006 FON Technology, SL.
* Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
* Copyright (C) 2007 Othello <bach_ag@hotmail.com>
*/
/*
* Support for AR531X GPIO -- General Purpose Input/Output Pins
*/
#include <linux/autoconf.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <asm/addrspace.h>
#include <asm/io.h>
#include <asm/irq_cpu.h>
#include <asm/gpio.h>
#include "ar531x.h"
/*
GPIO Interrupt Support
Make use of request_irq() and the function gpio_to_irq() to trap gpio events
*/
/* Global variables */
static u32 ar531x_gpio_intr_Mask = 0;
/*
AR5312: I don't have any devices with this chip. Assumed to be similar to AR5215
will someone who has one try the code and remove this message if it works?
*/
#ifdef CONFIG_ATHEROS_AR5315
/*
AR5315: Up to 2 GPIO pins may be monitored simultaneously
specifying more pins if you already have 2 will not have any effect
however, the excess gpio irqs will also be triggered if a valid gpio being monitored triggers
only high, low or edge triggered interrupt supported
*/
static unsigned int ar5315_gpio_set_type_gpio = 0;
static unsigned int ar5315_gpio_set_type_lvl = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
#endif
#ifdef CONFIG_ATHEROS_AR5312
/* Enable the specified AR5312_GPIO_IRQ interrupt */
static void ar5312_gpio_intr_enable(unsigned int irq) {
u32 reg;
unsigned int gpio;
unsigned int imr;
gpio = irq - (AR531X_GPIO_IRQ(0));
if (gpio >= AR531X_NUM_GPIO)
return;
ar531x_gpio_intr_Mask |= (1<<gpio);
reg = sysRegRead(AR531X_GPIO_CR);
reg &= ~(AR531X_GPIO_CR_M(gpio) | AR531X_GPIO_CR_UART(gpio) | AR531X_GPIO_CR_INT(gpio));
reg |= AR531X_GPIO_CR_I(gpio);
reg |= AR531X_GPIO_CR_INT(gpio);
sysRegWrite(AR531X_GPIO_CR, reg);
(void)sysRegRead(AR531X_GPIO_CR); /* flush to hardware */
imr = sysRegRead(AR531X_IMR);
imr |= AR531X_ISR_GPIO;
sysRegWrite(AR531X_IMR, imr);
imr = sysRegRead(AR531X_IMR); /* flush write buffer */
}
/* Disable the specified AR5312_GPIO_IRQ interrupt */
static void ar5312_gpio_intr_disable(unsigned int irq) {
u32 reg;
unsigned int gpio;
gpio = irq - (AR531X_GPIO_IRQ(0));
if (gpio >= AR531X_NUM_GPIO)
return;
reg = sysRegRead(AR531X_GPIO_CR);
reg &= ~(AR531X_GPIO_CR_M(gpio) | AR531X_GPIO_CR_UART(gpio) | AR531X_GPIO_CR_INT(gpio));
reg |= AR531X_GPIO_CR_I(gpio);
/* No GPIO_CR_INT bit */
sysRegWrite(AR531X_GPIO_CR, reg);
(void)sysRegRead(AR531X_GPIO_CR); /* flush to hardware */
/* Disable Interrupt if no gpio needs triggering */
if (ar531x_gpio_intr_Mask != 0) {
unsigned int imr;
imr = sysRegRead(AR531X_IMR);
imr &= ~AR531X_ISR_GPIO;
sysRegWrite(AR531X_IMR, imr);
imr = sysRegRead(AR531X_IMR); /* flush write buffer */
}
ar531x_gpio_intr_Mask &= ~(1<<gpio);
}
/* Turn on the specified AR5312_GPIO_IRQ interrupt */
static unsigned int ar5312_gpio_intr_startup(unsigned int irq) {
ar5312_gpio_intr_enable(irq);
return 0;
}
static void ar5312_gpio_intr_end(unsigned int irq) {
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
ar5312_gpio_intr_enable(irq);
}
asmlinkage void ar5312_gpio_irq_dispatch(void) {
int i;
u32 gpioIntPending;
gpioIntPending = sysRegRead(AR531X_GPIO_DI) & ar531x_gpio_intr_Mask;
sysRegWrite(AR531X_ISR, sysRegRead(AR531X_IMR) | ~AR531X_ISR_GPIO);
for (i=0; i<AR531X_GPIO_IRQ_COUNT; i++) {
if (gpioIntPending & (1 << i))
do_IRQ(AR531X_GPIO_IRQ(i));
}
}
#endif /* #ifdef CONFIG_ATHEROS_AR5312 */
#ifdef CONFIG_ATHEROS_AR5315
/* Enable the specified AR5315_GPIO_IRQ interrupt */
static void ar5315_gpio_intr_enable(unsigned int irq) {
u32 reg;
unsigned int gpio;
unsigned int imr;
unsigned int i;
gpio = irq - (AR531X_GPIO_IRQ(0));
if (gpio >= AR5315_NUM_GPIO)
return;
ar531x_gpio_intr_Mask |= (1<<gpio);
reg = sysRegRead(AR5315_GPIO_CR);
reg &= ~(AR5315_GPIO_CR_M(gpio));
reg |= AR5315_GPIO_CR_I(gpio);
sysRegWrite(AR5315_GPIO_CR, reg);
(void)sysRegRead(AR5315_GPIO_CR); /* flush write to hardware */
/* Locate a free register slot to enable gpio intr
will fail silently if no more slots are available
*/
reg = sysRegRead(AR5315_GPIO_INT);
for (i=0 ; i<=AR5315_GPIO_INT_MAX_Y ; i++) {
/* Free slot means trigger level = 0 */
if ( AR5315_GPIO_INT_LVL_OFF ==
(reg & AR5315_GPIO_INT_LVL_M) ) {
unsigned int def_lvl = AR5315_GPIO_INT_LVL_EDGE;
if (ar5315_gpio_set_type_gpio == gpio)
def_lvl = ar5315_gpio_set_type_lvl;
/* Set the gpio level trigger mode */
/* reg &= ~(AR5315_GPIO_INT_LVL_M(i)); */
reg |= AR5315_GPIO_INT_LVL(i);
/* Enable the gpio pin */
reg &= ~(AR5315_GPIO_INT_M);
reg |= AR5315_GPIO_INT_S(i);
sysRegWrite(AR5315_GPIO_INT, reg);
(void)sysRegRead(AR5315_GPIO_INT); /* flush write to hardware */
/* break out of for loop */
break;
} /* end if trigger level for slot i is 0 */
} /* end for each slot */
imr = sysRegRead(AR5315_IMR);
imr |= AR5315_ISR_GPIO;
sysRegWrite(AR5315_IMR, imr);
imr = sysRegRead(AR5315_IMR); /* flush write buffer */
}
/* Disable the specified AR5315_GPIO_IRQ interrupt */
static void ar5315_gpio_intr_disable(unsigned int irq) {
u32 reg;
unsigned int gpio;
unsigned int i;
gpio = irq - (AR531X_GPIO_IRQ(0));
if (gpio >= AR5315_NUM_GPIO)
return;
reg = sysRegRead(AR5315_GPIO_CR);
reg &= ~(AR5315_GPIO_CR_M(gpio));
reg |= AR5315_GPIO_CR_I(gpio);
sysRegWrite(AR5315_GPIO_CR, reg);
(void)sysRegRead(AR5315_GPIO_CR); /* flush write to hardware */
/* Locate a the correct register slot to disable gpio intr */
reg = sysRegRead(AR5315_GPIO_INT);
for (i=0 ; i<=AR5315_GPIO_INT_MAX_Y ; i++) {
/* If this correct */
if ( AR5315_GPIO_INT_S(i) ==
(reg & AR5315_GPIO_INT_M) ) {
/* Clear the gpio level trigger mode */
reg &= ~(AR5315_GPIO_INT_LVL_M);
sysRegWrite(AR5315_GPIO_INT, reg);
(void)sysRegRead(AR5315_GPIO_INT); /* flush write to hardware */
break;
} /* end if trigger level for slot i is 0 */
} /* end for each slot */
/* Disable interrupt only if no gpio needs triggering */
if (ar531x_gpio_intr_Mask != 0) {
unsigned int imr;
imr = sysRegRead(AR5315_IMR);
imr &= ~AR5315_ISR_GPIO;
sysRegWrite(AR5315_IMR, imr);
imr = sysRegRead(AR5315_IMR); /* flush write buffer */
}
ar531x_gpio_intr_Mask &= ~(1<<gpio);
}
/* Turn on the specified AR5315_GPIO_IRQ interrupt */
static unsigned int ar5315_gpio_intr_startup(unsigned int irq) {
ar5315_gpio_intr_enable(irq);
return 0;
}
static void ar5315_gpio_intr_end(unsigned int irq) {
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
ar5315_gpio_intr_enable(irq);
}
static int ar5315_gpio_intr_set_type(unsigned int irq, unsigned int flow_type) {
ar5315_gpio_set_type_gpio = irq - (AR531X_GPIO_IRQ(0));
if (ar5315_gpio_set_type_gpio > AR5315_NUM_GPIO)
return -EINVAL;
switch (flow_type & IRQF_TRIGGER_MASK) {
case IRQF_TRIGGER_RISING:
case IRQF_TRIGGER_FALLING:
printk(KERN_WARNING "AR5315 GPIO %u falling back to edge triggered\n", ar5315_gpio_set_type_gpio);
case IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING:
ar5315_gpio_set_type_lvl = AR5315_GPIO_INT_LVL_EDGE;
break;
case IRQF_TRIGGER_LOW:
ar5315_gpio_set_type_lvl = AR5315_GPIO_INT_LVL_LOW;
break;
case IRQF_TRIGGER_HIGH:
ar5315_gpio_set_type_lvl = AR5315_GPIO_INT_LVL_HIGH;
break;
default:
return -EINVAL;
}
return 0;
}
asmlinkage void ar5315_gpio_irq_dispatch(void){
int i;
u32 gpioIntPending;
gpioIntPending = sysRegRead(AR5315_GPIO_DI) & ar531x_gpio_intr_Mask;
sysRegWrite(AR5315_ISR, sysRegRead(AR5315_IMR) | ~AR5315_ISR_GPIO);
for (i=0; i<AR531X_GPIO_IRQ_COUNT; i++) {
if (gpioIntPending & (1 << i))
do_IRQ(AR531X_GPIO_IRQ(i));
}
}
#endif /* #ifdef CONFIG_ATHEROS_AR5315 */
/* Common Code */
static struct irq_chip ar531x_gpio_intr_controller = {
.typename = "AR531X GPIO",
};
/* ARGSUSED */
irqreturn_t
spurious_gpio_handler(int cpl, void *dev_id)
{
u32 gpioDataIn;
DO_AR5312(gpioDataIn = sysRegRead(AR531X_GPIO_DI);)
DO_AR5315(gpioDataIn = sysRegRead(AR5315_GPIO_DI);)
printk("spurious_gpio_handler: 0x%08x dev=%p DI=0x%08x gpioIntMask=0x%08x\n",
cpl, dev_id, gpioDataIn, ar531x_gpio_intr_Mask);
return IRQ_NONE;
}
static struct irqaction spurious_gpio = {
.handler = spurious_gpio_handler,
.name = "spurious_gpio",
};
/* Initialize AR531X GPIO interrupts */
static int __init ar531x_gpio_init(void)
{
int i;
DO_AR5312( \
ar531x_gpio_intr_controller.startup = ar5312_gpio_intr_startup; \
ar531x_gpio_intr_controller.shutdown = ar5312_gpio_intr_disable; \
ar531x_gpio_intr_controller.enable = ar5312_gpio_intr_enable; \
ar531x_gpio_intr_controller.disable = ar5312_gpio_intr_disable; \
ar531x_gpio_intr_controller.ack = ar5312_gpio_intr_disable; \
ar531x_gpio_intr_controller.end = ar5312_gpio_intr_end; \
)
DO_AR5315( \
ar531x_gpio_intr_controller.startup = ar5315_gpio_intr_startup; \
ar531x_gpio_intr_controller.shutdown = ar5315_gpio_intr_disable; \
ar531x_gpio_intr_controller.enable = ar5315_gpio_intr_enable; \
ar531x_gpio_intr_controller.disable = ar5315_gpio_intr_disable; \
ar531x_gpio_intr_controller.ack = ar5315_gpio_intr_disable; \
ar531x_gpio_intr_controller.end = ar5315_gpio_intr_end; \
ar531x_gpio_intr_controller.set_type = ar5315_gpio_intr_set_type; \
)
for (i = AR531X_GPIO_IRQ_BASE;
i < AR531X_GPIO_IRQ_BASE + AR531X_GPIO_IRQ_COUNT;
i++) {
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = NULL;
irq_desc[i].depth = 1;
irq_desc[i].chip = &ar531x_gpio_intr_controller;
}
setup_irq(AR531X_GPIO_IRQ_NONE, &spurious_gpio);
return 0;
}
subsys_initcall(ar531x_gpio_init);