android_kernel_xiaomi_sm8350/drivers/gpio/gpio-mxc.c
Shawn Guo 7e6086d9e5 gpio/mxc: specify gpio base for device tree probe
Currently, unlike the non-DT probe where the gpio base is specified
with pdev->id, the DT probe uses the base dynamically allocated by
gpio core, which uses a completely different numbering scheme.  This
causes two issues to user space applications which access sysfs entry
/sys/class/gpio/gpioN.

* It breaks the compatibility with user space applications between
  non-DT and DT kernels.

* It's not intuitive and sometimes hard for users to map the Linux
  gpio number to the actual hardware pin.

Use alias to identify the gpio port/bank, and then the gpio base
can be specified with port id to solve above issues.  If alias is not
defined in device tree, the base number dynamically allocated by gpio
core will be used.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-08-07 08:55:22 +02:00

532 lines
14 KiB
C

/*
* 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/irqdomain.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/basic_mmio_gpio.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <asm-generic/bug.h>
#include <asm/mach/irq.h>
enum mxc_gpio_hwtype {
IMX1_GPIO, /* runs on i.mx1 */
IMX21_GPIO, /* runs on i.mx21 and i.mx27 */
IMX31_GPIO, /* runs on i.mx31 */
IMX35_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;
int edge_sel_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;
struct irq_domain *domain;
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,
.edge_sel_reg = -EINVAL,
.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,
.edge_sel_reg = -EINVAL,
.low_level = 0x00,
.high_level = 0x01,
.rise_edge = 0x02,
.fall_edge = 0x03,
};
static struct mxc_gpio_hwdata imx35_gpio_hwdata = {
.dr_reg = 0x00,
.gdir_reg = 0x04,
.psr_reg = 0x08,
.icr1_reg = 0x0c,
.icr2_reg = 0x10,
.imr_reg = 0x14,
.isr_reg = 0x18,
.edge_sel_reg = 0x1c,
.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_EDGE_SEL (mxc_gpio_hwdata->edge_sel_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_BOTH_EDGES 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,
}, {
.name = "imx35-gpio",
.driver_data = IMX35_GPIO,
}, {
/* sentinel */
}
};
static const struct of_device_id mxc_gpio_dt_ids[] = {
{ .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], },
{ .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], },
{ .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], },
{ .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_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)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxc_gpio_port *port = gc->private;
u32 bit, val;
u32 gpio_idx = d->hwirq;
u32 gpio = port->bgc.gc.base + gpio_idx;
int edge;
void __iomem *reg = port->base;
port->both_edges &= ~(1 << gpio_idx);
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:
if (GPIO_EDGE_SEL >= 0) {
edge = GPIO_INT_BOTH_EDGES;
} else {
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_idx;
}
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;
}
if (GPIO_EDGE_SEL >= 0) {
val = readl(port->base + GPIO_EDGE_SEL);
if (edge == GPIO_INT_BOTH_EDGES)
writel(val | (1 << gpio_idx),
port->base + GPIO_EDGE_SEL);
else
writel(val & ~(1 << gpio_idx),
port->base + GPIO_EDGE_SEL);
}
if (edge != GPIO_INT_BOTH_EDGES) {
reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
bit = gpio_idx & 0xf;
val = readl(reg) & ~(0x3 << (bit << 1));
writel(val | (edge << (bit << 1)), reg);
}
writel(1 << gpio_idx, 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)
{
while (irq_stat != 0) {
int irqoffset = fls(irq_stat) - 1;
if (port->both_edges & (1 << irqoffset))
mxc_flip_edge(port, irqoffset);
generic_handle_irq(irq_find_mapping(port->domain, 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);
struct irq_chip *chip = irq_get_chip(irq);
chained_irq_enter(chip, desc);
irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
mxc_gpio_irq_handler(port, irq_stat);
chained_irq_exit(chip, desc);
}
/* 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)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct mxc_gpio_port *port = gc->private;
u32 gpio_idx = d->hwirq;
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, int irq_base)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_alloc_generic_chip("gpio-mxc", 1, irq_base,
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 = 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)
{
const struct of_device_id *of_id =
of_match_device(mxc_gpio_dt_ids, &pdev->dev);
enum mxc_gpio_hwtype hwtype;
if (of_id)
pdev->id_entry = of_id->data;
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 == IMX35_GPIO)
mxc_gpio_hwdata = &imx35_gpio_hwdata;
else if (hwtype == IMX31_GPIO)
mxc_gpio_hwdata = &imx31_gpio_hwdata;
else
mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
mxc_gpio_hwtype = hwtype;
}
static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
struct bgpio_chip *bgc = to_bgpio_chip(gc);
struct mxc_gpio_port *port =
container_of(bgc, struct mxc_gpio_port, bgc);
return irq_find_mapping(port->domain, offset);
}
static int __devinit mxc_gpio_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct mxc_gpio_port *port;
struct resource *iores;
int irq_base;
int err;
mxc_gpio_get_hw(pdev);
port = kzalloc(sizeof(struct mxc_gpio_port), GFP_KERNEL);
if (!port)
return -ENOMEM;
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);
if (mxc_gpio_hwtype == IMX21_GPIO) {
/*
* Setup one handler for all GPIO interrupts. Actually setting
* the handler is needed only once, but doing it for every port
* is more robust and easier.
*/
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, 0);
if (err)
goto out_iounmap;
port->bgc.gc.to_irq = mxc_gpio_to_irq;
port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
pdev->id * 32;
err = gpiochip_add(&port->bgc.gc);
if (err)
goto out_bgpio_remove;
irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
if (irq_base < 0) {
err = irq_base;
goto out_gpiochip_remove;
}
port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
&irq_domain_simple_ops, NULL);
if (!port->domain) {
err = -ENODEV;
goto out_irqdesc_free;
}
/* gpio-mxc can be a generic irq chip */
mxc_gpio_init_gc(port, irq_base);
list_add_tail(&port->node, &mxc_gpio_ports);
return 0;
out_irqdesc_free:
irq_free_descs(irq_base, 32);
out_gpiochip_remove:
WARN_ON(gpiochip_remove(&port->bgc.gc) < 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,
.of_match_table = mxc_gpio_dt_ids,
},
.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");