/*
* 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 <asm-generic/bug.h>
enum mxc_gpio_hwtype {
IMX1_GPIO, /* runs on i.mx1 */
IMX21_GPIO, /* runs on i.mx21 and i.mx27 */
IMX31_GPIO, /* runs on all other i.mx */
};
/* device type dependent stuff */
struct mxc_gpio_hwdata {
unsigned dr_reg;
unsigned gdir_reg;
unsigned psr_reg;
unsigned icr1_reg;
unsigned icr2_reg;
unsigned imr_reg;
unsigned isr_reg;
unsigned low_level;
unsigned high_level;
unsigned rise_edge;
unsigned fall_edge;
};
struct mxc_gpio_port {
struct list_head node;
void __iomem *base;
int irq;
int irq_high;
int virtual_irq_start;
struct bgpio_chip bgc;
u32 both_edges;
};
static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = {
.dr_reg = 0x1c,
.gdir_reg = 0x00,
.psr_reg = 0x24,
.icr1_reg = 0x28,
.icr2_reg = 0x2c,
.imr_reg = 0x30,
.isr_reg = 0x34,
.low_level = 0x03,
.high_level = 0x02,
.rise_edge = 0x00,
.fall_edge = 0x01,
};
static struct mxc_gpio_hwdata imx31_gpio_hwdata = {
.dr_reg = 0x00,
.gdir_reg = 0x04,
.psr_reg = 0x08,
.icr1_reg = 0x0c,
.icr2_reg = 0x10,
.imr_reg = 0x14,
.isr_reg = 0x18,
.low_level = 0x00,
.high_level = 0x01,
.rise_edge = 0x02,
.fall_edge = 0x03,
};
static enum mxc_gpio_hwtype mxc_gpio_hwtype;
static struct mxc_gpio_hwdata *mxc_gpio_hwdata;
#define GPIO_DR (mxc_gpio_hwdata->dr_reg)
#define GPIO_GDIR (mxc_gpio_hwdata->gdir_reg)
#define GPIO_PSR (mxc_gpio_hwdata->psr_reg)
#define GPIO_ICR1 (mxc_gpio_hwdata->icr1_reg)
#define GPIO_ICR2 (mxc_gpio_hwdata->icr2_reg)
#define GPIO_IMR (mxc_gpio_hwdata->imr_reg)
#define GPIO_ISR (mxc_gpio_hwdata->isr_reg)
#define GPIO_INT_LOW_LEV (mxc_gpio_hwdata->low_level)
#define GPIO_INT_HIGH_LEV (mxc_gpio_hwdata->high_level)
#define GPIO_INT_RISE_EDGE (mxc_gpio_hwdata->rise_edge)
#define GPIO_INT_FALL_EDGE (mxc_gpio_hwdata->fall_edge)
#define GPIO_INT_NONE 0x4
static struct platform_device_id mxc_gpio_devtype[] = {
{
.name = "imx1-gpio",
.driver_data = IMX1_GPIO,
}, {
.name = "imx21-gpio",
.driver_data = IMX21_GPIO,
}, {
.name = "imx31-gpio",
.driver_data = IMX31_GPIO,
}, {
/* sentinel */
}
};
/*
* MX2 has one interrupt *for all* gpio ports. The list is used
* to save the references to all ports, so that mx2_gpio_irq_handler
* can walk through all interrupt status registers.
*/
static LIST_HEAD(mxc_gpio_ports);
/* Note: This driver assumes 32 GPIOs are handled in one register */
static int gpio_set_irq_type(struct irq_data *d, u32 type)
{
u32 gpio = irq_to_gpio(d->irq);
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxc_gpio_port *port = gc->private;
u32 bit, val;
int edge;
void __iomem *reg = port->base;
port->both_edges &= ~(1 << (gpio & 31));
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_EDGE_BOTH:
val = gpio_get_value(gpio);
if (val) {
edge = GPIO_INT_LOW_LEV;
pr_debug("mxc: set GPIO %d to low trigger\n", gpio);
} else {
edge = GPIO_INT_HIGH_LEV;
pr_debug("mxc: set GPIO %d to high trigger\n", gpio);
}
port->both_edges |= 1 << (gpio & 31);
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;
}
reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
bit = gpio & 0xf;
val = readl(reg) & ~(0x3 << (bit << 1));
writel(val | (edge << (bit << 1)), reg);
writel(1 << (gpio & 0x1f), port->base + GPIO_ISR);
return 0;
}
static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
{
void __iomem *reg = port->base;
u32 bit, val;
int edge;
reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
bit = gpio & 0xf;
val = readl(reg);
edge = (val >> (bit << 1)) & 3;
val &= ~(0x3 << (bit << 1));
if (edge == GPIO_INT_HIGH_LEV) {
edge = GPIO_INT_LOW_LEV;
pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
} else if (edge == GPIO_INT_LOW_LEV) {
edge = GPIO_INT_HIGH_LEV;
pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
} else {
pr_err("mxc: invalid configuration for GPIO %d: %x\n",
gpio, edge);
return;
}
writel(val | (edge << (bit << 1)), reg);
}
/* handle 32 interrupts in one status register */
static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
{
u32 gpio_irq_no_base = port->virtual_irq_start;
while (irq_stat != 0) {
int irqoffset = fls(irq_stat) - 1;
if (port->both_edges & (1 << irqoffset))
mxc_flip_edge(port, irqoffset);
generic_handle_irq(gpio_irq_no_base + irqoffset);
irq_stat &= ~(1 << irqoffset);
}
}
/* MX1 and MX3 has one interrupt *per* gpio port */
static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc)
{
u32 irq_stat;
struct mxc_gpio_port *port = irq_get_handler_data(irq);
irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
mxc_gpio_irq_handler(port, irq_stat);
}
/* MX2 has one interrupt *for all* gpio ports */
static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc)
{
u32 irq_msk, irq_stat;
struct mxc_gpio_port *port;
/* walk through all interrupt status registers */
list_for_each_entry(port, &mxc_gpio_ports, node) {
irq_msk = readl(port->base + GPIO_IMR);
if (!irq_msk)
continue;
irq_stat = readl(port->base + GPIO_ISR) & irq_msk;
if (irq_stat)
mxc_gpio_irq_handler(port, irq_stat);
}
}
/*
* 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 gpio_set_wake_irq(struct irq_data *d, u32 enable)
{
u32 gpio = irq_to_gpio(d->irq);
u32 gpio_idx = gpio & 0x1F;
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxc_gpio_port *port = gc->private;
if (enable) {
if (port->irq_high && (gpio_idx >= 16))
enable_irq_wake(port->irq_high);
else
enable_irq_wake(port->irq);
} else {
if (port->irq_high && (gpio_idx >= 16))
disable_irq_wake(port->irq_high);
else
disable_irq_wake(port->irq);
}
return 0;
}
static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_alloc_generic_chip("gpio-mxc", 1, port->virtual_irq_start,
port->base, handle_level_irq);
gc->private = port;
ct = gc->chip_types;
ct->chip.irq_ack = irq_gc_ack,
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_set_type = gpio_set_irq_type;
ct->chip.irq_set_wake = gpio_set_wake_irq,
ct->regs.ack = GPIO_ISR;
ct->regs.mask = GPIO_IMR;
irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK,
IRQ_NOREQUEST, 0);
}
static void __devinit mxc_gpio_get_hw(struct platform_device *pdev)
{
enum mxc_gpio_hwtype hwtype = pdev->id_entry->driver_data;
if (mxc_gpio_hwtype) {
/*
* The driver works with a reasonable presupposition,
* that is all gpio ports must be the same type when
* running on one soc.
*/
BUG_ON(mxc_gpio_hwtype != hwtype);
return;
}
if (hwtype == IMX31_GPIO)
mxc_gpio_hwdata = &imx31_gpio_hwdata;
else
mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
mxc_gpio_hwtype = hwtype;
}
static int __devinit mxc_gpio_probe(struct platform_device *pdev)
{
struct mxc_gpio_port *port;
struct resource *iores;
int err;
mxc_gpio_get_hw(pdev);
port = kzalloc(sizeof(struct mxc_gpio_port), GFP_KERNEL);
if (!port)
return -ENOMEM;
port->virtual_irq_start = MXC_GPIO_IRQ_START + pdev->id * 32;
iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!iores) {
err = -ENODEV;
goto out_kfree;
}
if (!request_mem_region(iores->start, resource_size(iores),
pdev->name)) {
err = -EBUSY;
goto out_kfree;
}
port->base = ioremap(iores->start, resource_size(iores));
if (!port->base) {
err = -ENOMEM;
goto out_release_mem;
}
port->irq_high = platform_get_irq(pdev, 1);
port->irq = platform_get_irq(pdev, 0);
if (port->irq < 0) {
err = -EINVAL;
goto out_iounmap;
}
/* disable the interrupt and clear the status */
writel(0, port->base + GPIO_IMR);
writel(~0, port->base + GPIO_ISR);
/* gpio-mxc can be a generic irq chip */
mxc_gpio_init_gc(port);
if (mxc_gpio_hwtype == IMX21_GPIO) {
/* setup one handler for all GPIO interrupts */
if (pdev->id == 0)
irq_set_chained_handler(port->irq,
mx2_gpio_irq_handler);
} else {
/* setup one handler for each entry */
irq_set_chained_handler(port->irq, mx3_gpio_irq_handler);
irq_set_handler_data(port->irq, port);
if (port->irq_high > 0) {
/* setup handler for GPIO 16 to 31 */
irq_set_chained_handler(port->irq_high,
mx3_gpio_irq_handler);
irq_set_handler_data(port->irq_high, port);
}
}
err = bgpio_init(&port->bgc, &pdev->dev, 4,
port->base + GPIO_PSR,
port->base + GPIO_DR, NULL,
port->base + GPIO_GDIR, NULL, false);
if (err)
goto out_iounmap;
port->bgc.gc.base = pdev->id * 32;
port->bgc.dir = port->bgc.read_reg(port->bgc.reg_dir);
port->bgc.data = port->bgc.read_reg(port->bgc.reg_set);
err = gpiochip_add(&port->bgc.gc);
if (err)
goto out_bgpio_remove;
list_add_tail(&port->node, &mxc_gpio_ports);
return 0;
out_bgpio_remove:
bgpio_remove(&port->bgc);
out_iounmap:
iounmap(port->base);
out_release_mem:
release_mem_region(iores->start, resource_size(iores));
out_kfree:
kfree(port);
dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
return err;
}
static struct platform_driver mxc_gpio_driver = {
.driver = {
.name = "gpio-mxc",
.owner = THIS_MODULE,
},
.probe = mxc_gpio_probe,
.id_table = mxc_gpio_devtype,
};
static int __init gpio_mxc_init(void)
{
return platform_driver_register(&mxc_gpio_driver);
}
postcore_initcall(gpio_mxc_init);
MODULE_AUTHOR("Freescale Semiconductor, "
"Daniel Mack <danielncaiaq.de>, "
"Juergen Beisert <kernel@pengutronix.de>");
MODULE_DESCRIPTION("Freescale MXC GPIO");
MODULE_LICENSE("GPL");
