/*
* MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
*
* Based on code from Freescale,
* Copyright (C) 2004-2010 Freescale Semiconductor, 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
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/basic_mmio_gpio.h>
#include <linux/module.h>
#include <mach/mxs.h>
#define MXS_SET 0x4
#define MXS_CLR 0x8
#define PINCTRL_DOUT(n) ((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
#define PINCTRL_DIN(n) ((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
#define PINCTRL_DOE(n) ((cpu_is_mx23() ? 0x0700 : 0x0b00) + (n) * 0x10)
#define PINCTRL_PIN2IRQ(n) ((cpu_is_mx23() ? 0x0800 : 0x1000) + (n) * 0x10)
#define PINCTRL_IRQEN(n) ((cpu_is_mx23() ? 0x0900 : 0x1100) + (n) * 0x10)
#define PINCTRL_IRQLEV(n) ((cpu_is_mx23() ? 0x0a00 : 0x1200) + (n) * 0x10)
#define PINCTRL_IRQPOL(n) ((cpu_is_mx23() ? 0x0b00 : 0x1300) + (n) * 0x10)
#define PINCTRL_IRQSTAT(n) ((cpu_is_mx23() ? 0x0c00 : 0x1400) + (n) * 0x10)
#define GPIO_INT_FALL_EDGE 0x0
#define GPIO_INT_LOW_LEV 0x1
#define GPIO_INT_RISE_EDGE 0x2
#define GPIO_INT_HIGH_LEV 0x3
#define GPIO_INT_LEV_MASK (1 << 0)
#define GPIO_INT_POL_MASK (1 << 1)
#define irq_to_gpio(irq) ((irq) - MXS_GPIO_IRQ_START)
struct mxs_gpio_port {
void __iomem *base;
int id;
int irq;
int virtual_irq_start;
struct bgpio_chip bgc;
};
/* Note: This driver assumes 32 GPIOs are handled in one register */
static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
{
u32 gpio = irq_to_gpio(d->irq);
u32 pin_mask = 1 << (gpio & 31);
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxs_gpio_port *port = gc->private;
void __iomem *pin_addr;
int edge;
switch (type) {
case IRQ_TYPE_EDGE_RISING:
edge = GPIO_INT_RISE_EDGE;
break;
case IRQ_TYPE_EDGE_FALLING:
edge = GPIO_INT_FALL_EDGE;
break;
case IRQ_TYPE_LEVEL_LOW:
edge = GPIO_INT_LOW_LEV;
break;
case IRQ_TYPE_LEVEL_HIGH:
edge = GPIO_INT_HIGH_LEV;
break;
default:
return -EINVAL;
}
/* set level or edge */
pin_addr = port->base + PINCTRL_IRQLEV(port->id);
if (edge & GPIO_INT_LEV_MASK)
writel(pin_mask, pin_addr + MXS_SET);
else
writel(pin_mask, pin_addr + MXS_CLR);
/* set polarity */
pin_addr = port->base + PINCTRL_IRQPOL(port->id);
if (edge & GPIO_INT_POL_MASK)
writel(pin_mask, pin_addr + MXS_SET);
else
writel(pin_mask, pin_addr + MXS_CLR);
writel(1 << (gpio & 0x1f),
port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
return 0;
}
/* MXS has one interrupt *per* gpio port */
static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
{
u32 irq_stat;
struct mxs_gpio_port *port = irq_get_handler_data(irq);
u32 gpio_irq_no_base = port->virtual_irq_start;
desc->irq_data.chip->irq_ack(&desc->irq_data);
irq_stat = readl(port->base + PINCTRL_IRQSTAT(port->id)) &
readl(port->base + PINCTRL_IRQEN(port->id));
while (irq_stat != 0) {
int irqoffset = fls(irq_stat) - 1;
generic_handle_irq(gpio_irq_no_base + irqoffset);
irq_stat &= ~(1 << irqoffset);
}
}
/*
* Set interrupt number "irq" in the GPIO as a wake-up source.
* While system is running, all registered GPIO interrupts need to have
* wake-up enabled. When system is suspended, only selected GPIO interrupts
* need to have wake-up enabled.
* @param irq interrupt source number
* @param enable enable as wake-up if equal to non-zero
* @return This function returns 0 on success.
*/
static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxs_gpio_port *port = gc->private;
if (enable)
enable_irq_wake(port->irq);
else
disable_irq_wake(port->irq);
return 0;
}
static void __init mxs_gpio_init_gc(struct mxs_gpio_port *port)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_alloc_generic_chip("gpio-mxs", 1, port->virtual_irq_start,
port->base, handle_level_irq);
gc->private = port;
ct = gc->chip_types;
ct->chip.irq_ack = irq_gc_ack_set_bit;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_set_type = mxs_gpio_set_irq_type;
ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
ct->regs.ack = PINCTRL_IRQSTAT(port->id) + MXS_CLR;
ct->regs.mask = PINCTRL_IRQEN(port->id);
irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
}
static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
struct bgpio_chip *bgc = to_bgpio_chip(gc);
struct mxs_gpio_port *port =
container_of(bgc, struct mxs_gpio_port, bgc);
return port->virtual_irq_start + offset;
}
static int __devinit mxs_gpio_probe(struct platform_device *pdev)
{
static void __iomem *base;
struct mxs_gpio_port *port;
struct resource *iores = NULL;
int err;
port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
port->id = pdev->id;
port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
port->irq = platform_get_irq(pdev, 0);
if (port->irq < 0)
return port->irq;
/*
* map memory region only once, as all the gpio ports
* share the same one
*/
if (!base) {
iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_request_and_ioremap(&pdev->dev, iores);
if (!base)
return -EADDRNOTAVAIL;
}
port->base = base;
/*
* select the pin interrupt functionality but initially
* disable the interrupts
*/
writel(~0U, port->base + PINCTRL_PIN2IRQ(port->id));
writel(0, port->base + PINCTRL_IRQEN(port->id));
/* clear address has to be used to clear IRQSTAT bits */
writel(~0U, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
/* gpio-mxs can be a generic irq chip */
mxs_gpio_init_gc(port);
/* setup one handler for each entry */
irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
irq_set_handler_data(port->irq, port);
err = bgpio_init(&port->bgc, &pdev->dev, 4,
port->base + PINCTRL_DIN(port->id),
port->base + PINCTRL_DOUT(port->id), NULL,
port->base + PINCTRL_DOE(port->id), NULL, false);
if (err)
return err;
port->bgc.gc.to_irq = mxs_gpio_to_irq;
port->bgc.gc.base = port->id * 32;
err = gpiochip_add(&port->bgc.gc);
if (err) {
bgpio_remove(&port->bgc);
return err;
}
return 0;
}
static struct platform_driver mxs_gpio_driver = {
.driver = {
.name = "gpio-mxs",
.owner = THIS_MODULE,
},
.probe = mxs_gpio_probe,
};
static int __init mxs_gpio_init(void)
{
return platform_driver_register(&mxs_gpio_driver);
}
postcore_initcall(mxs_gpio_init);
MODULE_AUTHOR("Freescale Semiconductor, "
"Daniel Mack <danielncaiaq.de>, "
"Juergen Beisert <kernel@pengutronix.de>");
MODULE_DESCRIPTION("Freescale MXS GPIO");
MODULE_LICENSE("GPL");
