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gpio/ep93xx: convert to platform_driver and use basic_mmio_gpio library
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This converts the gpio-ep93xx driver into a platform_driver and uses
the basic_mmio_gpio library.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
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H Hartley Sweeten authored and Grant Likely committed Jun 8, 2011
1 parent 6dd599f commit 1e4c884
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Showing 3 changed files with 140 additions and 128 deletions.
27 changes: 20 additions & 7 deletions arch/arm/mach-ep93xx/core.c
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Original file line number Diff line number Diff line change
Expand Up @@ -174,14 +174,10 @@ struct sys_timer ep93xx_timer = {
/*************************************************************************
* EP93xx IRQ handling
*************************************************************************/
extern void ep93xx_gpio_init_irq(void);

void __init ep93xx_init_irq(void)
{
vic_init(EP93XX_VIC1_BASE, 0, EP93XX_VIC1_VALID_IRQ_MASK, 0);
vic_init(EP93XX_VIC2_BASE, 32, EP93XX_VIC2_VALID_IRQ_MASK, 0);

ep93xx_gpio_init_irq();
}


Expand Down Expand Up @@ -240,6 +236,24 @@ unsigned int ep93xx_chip_revision(void)
return v;
}

/*************************************************************************
* EP93xx GPIO
*************************************************************************/
static struct resource ep93xx_gpio_resource[] = {
{
.start = EP93XX_GPIO_PHYS_BASE,
.end = EP93XX_GPIO_PHYS_BASE + 0xcc - 1,
.flags = IORESOURCE_MEM,
},
};

static struct platform_device ep93xx_gpio_device = {
.name = "gpio-ep93xx",
.id = -1,
.num_resources = ARRAY_SIZE(ep93xx_gpio_resource),
.resource = ep93xx_gpio_resource,
};

/*************************************************************************
* EP93xx peripheral handling
*************************************************************************/
Expand Down Expand Up @@ -866,14 +880,13 @@ void __init ep93xx_register_ac97(void)
platform_device_register(&ep93xx_pcm_device);
}

extern void ep93xx_gpio_init(void);

void __init ep93xx_init_devices(void)
{
/* Disallow access to MaverickCrunch initially */
ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_CPENA);

ep93xx_gpio_init();
/* Get the GPIO working early, other devices need it */
platform_device_register(&ep93xx_gpio_device);

amba_device_register(&uart1_device, &iomem_resource);
amba_device_register(&uart2_device, &iomem_resource);
Expand Down
1 change: 1 addition & 0 deletions drivers/gpio/Kconfig
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Original file line number Diff line number Diff line change
Expand Up @@ -87,6 +87,7 @@ config GPIO_IT8761E
config GPIO_EP93XX
def_bool y
depends on ARCH_EP93XX
select GPIO_GENERIC

config GPIO_EXYNOS4
def_bool y
Expand Down
240 changes: 119 additions & 121 deletions drivers/gpio/gpio-ep93xx.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@
* Generic EP93xx GPIO handling
*
* Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com>
* Copyright (c) 2011 H Hartley Sweeten <hsweeten@visionengravers.com>
*
* Based on code originally from:
* linux/arch/arm/mach-ep93xx/core.c
Expand All @@ -14,14 +15,20 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/init.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/basic_mmio_gpio.h>

#include <mach/hardware.h>

struct ep93xx_gpio {
void __iomem *mmio_base;
struct bgpio_chip bgc[8];
};

/*************************************************************************
* Interrupt handling for EP93xx on-chip GPIOs
*************************************************************************/
Expand Down Expand Up @@ -223,7 +230,7 @@ static struct irq_chip ep93xx_gpio_irq_chip = {
.irq_set_type = ep93xx_gpio_irq_type,
};

void __init ep93xx_gpio_init_irq(void)
static void ep93xx_gpio_init_irq(void)
{
int gpio_irq;

Expand Down Expand Up @@ -258,151 +265,142 @@ void __init ep93xx_gpio_init_irq(void)
/*************************************************************************
* gpiolib interface for EP93xx on-chip GPIOs
*************************************************************************/
struct ep93xx_gpio_chip {
struct gpio_chip chip;

void __iomem *data_reg;
void __iomem *data_dir_reg;
struct ep93xx_gpio_bank {
const char *label;
int data;
int dir;
int base;
bool has_debounce;
};

#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip)
#define EP93XX_GPIO_BANK(_label, _data, _dir, _base, _debounce) \
{ \
.label = _label, \
.data = _data, \
.dir = _dir, \
.base = _base, \
.has_debounce = _debounce, \
}

static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = {
EP93XX_GPIO_BANK("A", 0x00, 0x10, 0, true),
EP93XX_GPIO_BANK("B", 0x04, 0x14, 8, true),
EP93XX_GPIO_BANK("C", 0x08, 0x18, 40, false),
EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24, false),
EP93XX_GPIO_BANK("E", 0x20, 0x24, 32, false),
EP93XX_GPIO_BANK("F", 0x30, 0x34, 16, true),
EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48, false),
EP93XX_GPIO_BANK("H", 0x40, 0x44, 56, false),
};

static int ep93xx_gpio_set_debounce(struct gpio_chip *chip,
unsigned offset, unsigned debounce)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
u8 v;
int gpio = chip->base + offset;
int irq = gpio_to_irq(gpio);

local_irq_save(flags);
v = __raw_readb(ep93xx_chip->data_dir_reg);
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_dir_reg);
local_irq_restore(flags);
if (irq < 0)
return -EINVAL;

ep93xx_gpio_int_debounce(irq, debounce ? true : false);

return 0;
}

static int ep93xx_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int val)
static int ep93xx_gpio_add_bank(struct bgpio_chip *bgc, struct device *dev,
void __iomem *mmio_base, struct ep93xx_gpio_bank *bank)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
int line;
u8 v;

local_irq_save(flags);
void __iomem *data = mmio_base + bank->data;
void __iomem *dir = mmio_base + bank->dir;
int err;

/* Set the value */
v = __raw_readb(ep93xx_chip->data_reg);
if (val)
v |= (1 << offset);
else
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_reg);

/* Drive as an output */
line = chip->base + offset;
if (line <= EP93XX_GPIO_LINE_MAX_IRQ) {
/* Ports A/B/F */
ep93xx_gpio_int_mask(line);
ep93xx_gpio_update_int_params(line >> 3);
}
err = bgpio_init(bgc, dev, 1, data, NULL, NULL, dir, NULL, false);
if (err)
return err;

v = __raw_readb(ep93xx_chip->data_dir_reg);
v |= (1 << offset);
__raw_writeb(v, ep93xx_chip->data_dir_reg);
bgc->gc.label = bank->label;
bgc->gc.base = bank->base;

local_irq_restore(flags);
if (bank->has_debounce)
bgc->gc.set_debounce = ep93xx_gpio_set_debounce;

return 0;
return gpiochip_add(&bgc->gc);
}

static int ep93xx_gpio_get(struct gpio_chip *chip, unsigned offset)
static int __devinit ep93xx_gpio_probe(struct platform_device *pdev)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
struct ep93xx_gpio *ep93xx_gpio;
struct resource *res;
void __iomem *mmio;
int i;
int ret;

return !!(__raw_readb(ep93xx_chip->data_reg) & (1 << offset));
}
ep93xx_gpio = kzalloc(sizeof(*ep93xx_gpio), GFP_KERNEL);
if (!ep93xx_gpio)
return -ENOMEM;

static void ep93xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
unsigned long flags;
u8 v;

local_irq_save(flags);
v = __raw_readb(ep93xx_chip->data_reg);
if (val)
v |= (1 << offset);
else
v &= ~(1 << offset);
__raw_writeb(v, ep93xx_chip->data_reg);
local_irq_restore(flags);
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
ret = -ENXIO;
goto exit_free;
}

static int ep93xx_gpio_set_debounce(struct gpio_chip *chip,
unsigned offset, unsigned debounce)
{
int gpio = chip->base + offset;
int irq = gpio_to_irq(gpio);
if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
ret = -EBUSY;
goto exit_free;
}

if (irq < 0)
return -EINVAL;
mmio = ioremap(res->start, resource_size(res));
if (!mmio) {
ret = -ENXIO;
goto exit_release;
}
ep93xx_gpio->mmio_base = mmio;

ep93xx_gpio_int_debounce(irq, debounce ? true : false);
/* Default all ports to GPIO */
ep93xx_devcfg_set_bits(EP93XX_SYSCON_DEVCFG_KEYS |
EP93XX_SYSCON_DEVCFG_GONK |
EP93XX_SYSCON_DEVCFG_EONIDE |
EP93XX_SYSCON_DEVCFG_GONIDE |
EP93XX_SYSCON_DEVCFG_HONIDE);

return 0;
}
for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
struct bgpio_chip *bgc = &ep93xx_gpio->bgc[i];
struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i];

#define EP93XX_GPIO_BANK(name, dr, ddr, base_gpio) \
{ \
.chip = { \
.label = name, \
.direction_input = ep93xx_gpio_direction_input, \
.direction_output = ep93xx_gpio_direction_output, \
.get = ep93xx_gpio_get, \
.set = ep93xx_gpio_set, \
.base = base_gpio, \
.ngpio = 8, \
}, \
.data_reg = EP93XX_GPIO_REG(dr), \
.data_dir_reg = EP93XX_GPIO_REG(ddr), \
if (ep93xx_gpio_add_bank(bgc, &pdev->dev, mmio, bank))
dev_warn(&pdev->dev, "Unable to add gpio bank %s\n",
bank->label);
}

static struct ep93xx_gpio_chip ep93xx_gpio_banks[] = {
EP93XX_GPIO_BANK("A", 0x00, 0x10, 0),
EP93XX_GPIO_BANK("B", 0x04, 0x14, 8),
EP93XX_GPIO_BANK("C", 0x08, 0x18, 40),
EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24),
EP93XX_GPIO_BANK("E", 0x20, 0x24, 32),
EP93XX_GPIO_BANK("F", 0x30, 0x34, 16),
EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48),
EP93XX_GPIO_BANK("H", 0x40, 0x44, 56),
};
ep93xx_gpio_init_irq();

void __init ep93xx_gpio_init(void)
{
int i;
return 0;

/* Set Ports C, D, E, G, and H for GPIO use */
ep93xx_devcfg_set_bits(EP93XX_SYSCON_DEVCFG_KEYS |
EP93XX_SYSCON_DEVCFG_GONK |
EP93XX_SYSCON_DEVCFG_EONIDE |
EP93XX_SYSCON_DEVCFG_GONIDE |
EP93XX_SYSCON_DEVCFG_HONIDE);
exit_release:
release_mem_region(res->start, resource_size(res));
exit_free:
kfree(ep93xx_gpio);
dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, ret);
return ret;
}

for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
struct gpio_chip *chip = &ep93xx_gpio_banks[i].chip;

/*
* Ports A, B, and F support input debouncing when
* used as interrupts.
*/
if (!strcmp(chip->label, "A") ||
!strcmp(chip->label, "B") ||
!strcmp(chip->label, "F"))
chip->set_debounce = ep93xx_gpio_set_debounce;

gpiochip_add(chip);
}
static struct platform_driver ep93xx_gpio_driver = {
.driver = {
.name = "gpio-ep93xx",
.owner = THIS_MODULE,
},
.probe = ep93xx_gpio_probe,
};

static int __init ep93xx_gpio_init(void)
{
pr_info("%s\n", __func__);
return platform_driver_register(&ep93xx_gpio_driver);
}
postcore_initcall(ep93xx_gpio_init);

MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com> "
"H Hartley Sweeten <hsweeten@visionengravers.com>");
MODULE_DESCRIPTION("EP93XX GPIO driver");
MODULE_LICENSE("GPL");

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