blob: 836f1cc760c26d672bee7d79b37b362185c40a99 [file] [log] [blame] [edit]
// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIO driver for the IP block found in the Nomadik SoC; it is an AMBA device,
* managing 32 pins with alternate functions. It can also handle the STA2X11
* block from ST.
*
* The GPIO chips are shared with pinctrl-nomadik if used; it needs access for
* pinmuxing functionality and others.
*
* This driver also handles the mobileye,eyeq5-gpio compatible. It is an STA2X11
* but with only data, direction and interrupts register active. We want to
* avoid touching SLPM, RWIMSC, FWIMSC, AFSLA and AFSLB registers; that is,
* wake and alternate function registers. It is NOT compatible with
* pinctrl-nomadik.
*
* Copyright (C) 2008,2009 STMicroelectronics
* Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
* Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
* Copyright (C) 2011-2013 Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/cleanup.h>
#include <linux/clk.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/reset.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/gpio/gpio-nomadik.h>
#ifndef CONFIG_PINCTRL_NOMADIK
static DEFINE_SPINLOCK(nmk_gpio_slpm_lock);
#endif
void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip, unsigned int offset,
enum nmk_gpio_slpm mode)
{
u32 slpm;
/* We should NOT have been called. */
if (WARN_ON(nmk_chip->is_mobileye_soc))
return;
slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
if (mode == NMK_GPIO_SLPM_NOCHANGE)
slpm |= BIT(offset);
else
slpm &= ~BIT(offset);
writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
}
static void __nmk_gpio_set_output(struct nmk_gpio_chip *nmk_chip,
unsigned int offset, int val)
{
if (val)
writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DATS);
else
writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DATC);
}
void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
unsigned int offset, int val)
{
writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DIRS);
__nmk_gpio_set_output(nmk_chip, offset, val);
}
/* IRQ functions */
static void nmk_gpio_irq_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
clk_enable(nmk_chip->clk);
writel(BIT(d->hwirq), nmk_chip->addr + NMK_GPIO_IC);
clk_disable(nmk_chip->clk);
}
enum nmk_gpio_irq_type {
NORMAL,
WAKE,
};
static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
int offset, enum nmk_gpio_irq_type which,
bool enable)
{
u32 *rimscval;
u32 *fimscval;
u32 rimscreg;
u32 fimscreg;
if (which == NORMAL) {
rimscreg = NMK_GPIO_RIMSC;
fimscreg = NMK_GPIO_FIMSC;
rimscval = &nmk_chip->rimsc;
fimscval = &nmk_chip->fimsc;
} else {
/* We should NOT have been called. */
if (WARN_ON(nmk_chip->is_mobileye_soc))
return;
rimscreg = NMK_GPIO_RWIMSC;
fimscreg = NMK_GPIO_FWIMSC;
rimscval = &nmk_chip->rwimsc;
fimscval = &nmk_chip->fwimsc;
}
/* we must individually set/clear the two edges */
if (nmk_chip->edge_rising & BIT(offset)) {
if (enable)
*rimscval |= BIT(offset);
else
*rimscval &= ~BIT(offset);
writel(*rimscval, nmk_chip->addr + rimscreg);
}
if (nmk_chip->edge_falling & BIT(offset)) {
if (enable)
*fimscval |= BIT(offset);
else
*fimscval &= ~BIT(offset);
writel(*fimscval, nmk_chip->addr + fimscreg);
}
}
static void __nmk_gpio_set_wake(struct nmk_gpio_chip *nmk_chip,
int offset, bool on)
{
/* We should NOT have been called. */
if (WARN_ON(nmk_chip->is_mobileye_soc))
return;
/*
* Ensure WAKEUP_ENABLE is on. No need to disable it if wakeup is
* disabled, since setting SLPM to 1 increases power consumption, and
* wakeup is anyhow controlled by the RIMSC and FIMSC registers.
*/
if (nmk_chip->sleepmode && on) {
__nmk_gpio_set_slpm(nmk_chip, offset,
NMK_GPIO_SLPM_WAKEUP_ENABLE);
}
__nmk_gpio_irq_modify(nmk_chip, offset, WAKE, on);
}
static void nmk_gpio_irq_maskunmask(struct nmk_gpio_chip *nmk_chip,
struct irq_data *d, bool enable)
{
unsigned long flags;
clk_enable(nmk_chip->clk);
spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
spin_lock(&nmk_chip->lock);
__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, enable);
if (!nmk_chip->is_mobileye_soc && !(nmk_chip->real_wake & BIT(d->hwirq)))
__nmk_gpio_set_wake(nmk_chip, d->hwirq, enable);
spin_unlock(&nmk_chip->lock);
spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
clk_disable(nmk_chip->clk);
}
static void nmk_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
nmk_gpio_irq_maskunmask(nmk_chip, d, false);
gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}
static void nmk_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
gpiochip_enable_irq(gc, irqd_to_hwirq(d));
nmk_gpio_irq_maskunmask(nmk_chip, d, true);
}
static int nmk_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
unsigned long flags;
/* Handler is registered in all cases. */
if (nmk_chip->is_mobileye_soc)
return -ENXIO;
clk_enable(nmk_chip->clk);
spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
spin_lock(&nmk_chip->lock);
if (irqd_irq_disabled(d))
__nmk_gpio_set_wake(nmk_chip, d->hwirq, on);
if (on)
nmk_chip->real_wake |= BIT(d->hwirq);
else
nmk_chip->real_wake &= ~BIT(d->hwirq);
spin_unlock(&nmk_chip->lock);
spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
clk_disable(nmk_chip->clk);
return 0;
}
static int nmk_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
bool enabled = !irqd_irq_disabled(d);
bool wake = irqd_is_wakeup_set(d);
unsigned long flags;
if (type & IRQ_TYPE_LEVEL_HIGH)
return -EINVAL;
if (type & IRQ_TYPE_LEVEL_LOW)
return -EINVAL;
clk_enable(nmk_chip->clk);
spin_lock_irqsave(&nmk_chip->lock, flags);
if (enabled)
__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, false);
if (!nmk_chip->is_mobileye_soc && (enabled || wake))
__nmk_gpio_irq_modify(nmk_chip, d->hwirq, WAKE, false);
nmk_chip->edge_rising &= ~BIT(d->hwirq);
if (type & IRQ_TYPE_EDGE_RISING)
nmk_chip->edge_rising |= BIT(d->hwirq);
nmk_chip->edge_falling &= ~BIT(d->hwirq);
if (type & IRQ_TYPE_EDGE_FALLING)
nmk_chip->edge_falling |= BIT(d->hwirq);
if (enabled)
__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, true);
if (!nmk_chip->is_mobileye_soc && (enabled || wake))
__nmk_gpio_irq_modify(nmk_chip, d->hwirq, WAKE, true);
spin_unlock_irqrestore(&nmk_chip->lock, flags);
clk_disable(nmk_chip->clk);
return 0;
}
static unsigned int nmk_gpio_irq_startup(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
clk_enable(nmk_chip->clk);
nmk_gpio_irq_unmask(d);
return 0;
}
static void nmk_gpio_irq_shutdown(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
nmk_gpio_irq_mask(d);
clk_disable(nmk_chip->clk);
}
static irqreturn_t nmk_gpio_irq_handler(int irq, void *dev_id)
{
struct nmk_gpio_chip *nmk_chip = dev_id;
struct gpio_chip *chip = &nmk_chip->chip;
unsigned long mask = GENMASK(chip->ngpio - 1, 0);
unsigned long status;
int bit;
clk_enable(nmk_chip->clk);
status = readl(nmk_chip->addr + NMK_GPIO_IS);
/* Ensure we cannot leave pending bits; this should never occur. */
if (unlikely(status & ~mask))
writel(status & ~mask, nmk_chip->addr + NMK_GPIO_IC);
clk_disable(nmk_chip->clk);
for_each_set_bit(bit, &status, chip->ngpio)
generic_handle_domain_irq_safe(chip->irq.domain, bit);
return IRQ_RETVAL((status & mask) != 0);
}
/* I/O Functions */
static int nmk_gpio_get_dir(struct gpio_chip *chip, unsigned int offset)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
int dir;
clk_enable(nmk_chip->clk);
dir = readl(nmk_chip->addr + NMK_GPIO_DIR) & BIT(offset);
clk_disable(nmk_chip->clk);
if (dir)
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned int offset)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
clk_enable(nmk_chip->clk);
writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DIRC);
clk_disable(nmk_chip->clk);
return 0;
}
static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned int offset)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
int value;
clk_enable(nmk_chip->clk);
value = !!(readl(nmk_chip->addr + NMK_GPIO_DAT) & BIT(offset));
clk_disable(nmk_chip->clk);
return value;
}
static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned int offset,
int val)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
clk_enable(nmk_chip->clk);
__nmk_gpio_set_output(nmk_chip, offset, val);
clk_disable(nmk_chip->clk);
}
static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned int offset,
int val)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
clk_enable(nmk_chip->clk);
__nmk_gpio_make_output(nmk_chip, offset, val);
clk_disable(nmk_chip->clk);
return 0;
}
#ifdef CONFIG_DEBUG_FS
static int nmk_gpio_get_mode(struct nmk_gpio_chip *nmk_chip, int offset)
{
u32 afunc, bfunc;
/* We don't support modes. */
if (nmk_chip->is_mobileye_soc)
return NMK_GPIO_ALT_GPIO;
clk_enable(nmk_chip->clk);
afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & BIT(offset);
bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & BIT(offset);
clk_disable(nmk_chip->clk);
return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
}
void nmk_gpio_dbg_show_one(struct seq_file *s, struct pinctrl_dev *pctldev,
struct gpio_chip *chip, unsigned int offset,
unsigned int gpio)
{
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
int mode;
bool is_out;
bool data_out;
bool pull;
static const char * const modes[] = {
[NMK_GPIO_ALT_GPIO] = "gpio",
[NMK_GPIO_ALT_A] = "altA",
[NMK_GPIO_ALT_B] = "altB",
[NMK_GPIO_ALT_C] = "altC",
[NMK_GPIO_ALT_C + 1] = "altC1",
[NMK_GPIO_ALT_C + 2] = "altC2",
[NMK_GPIO_ALT_C + 3] = "altC3",
[NMK_GPIO_ALT_C + 4] = "altC4",
};
char *label = gpiochip_dup_line_label(chip, offset);
if (IS_ERR(label))
return;
clk_enable(nmk_chip->clk);
is_out = !!(readl(nmk_chip->addr + NMK_GPIO_DIR) & BIT(offset));
pull = !(readl(nmk_chip->addr + NMK_GPIO_PDIS) & BIT(offset));
data_out = !!(readl(nmk_chip->addr + NMK_GPIO_DAT) & BIT(offset));
mode = nmk_gpio_get_mode(nmk_chip, offset);
#ifdef CONFIG_PINCTRL_NOMADIK
if (mode == NMK_GPIO_ALT_C && pctldev)
mode = nmk_prcm_gpiocr_get_mode(pctldev, gpio);
#endif
if (is_out) {
seq_printf(s, " gpio-%-3d (%-20.20s) out %s %s",
gpio,
label ?: "(none)",
data_out ? "hi" : "lo",
(mode < 0) ? "unknown" : modes[mode]);
} else {
int irq = chip->to_irq(chip, offset);
const int pullidx = pull ? 1 : 0;
int val;
static const char * const pulls[] = {
"none ",
"pull enabled",
};
seq_printf(s, " gpio-%-3d (%-20.20s) in %s %s",
gpio,
label ?: "(none)",
pulls[pullidx],
(mode < 0) ? "unknown" : modes[mode]);
val = nmk_gpio_get_input(chip, offset);
seq_printf(s, " VAL %d", val);
/*
* This races with request_irq(), set_irq_type(),
* and set_irq_wake() ... but those are "rare".
*/
if (irq > 0 && irq_has_action(irq)) {
char *trigger;
bool wake;
if (nmk_chip->edge_rising & BIT(offset))
trigger = "edge-rising";
else if (nmk_chip->edge_falling & BIT(offset))
trigger = "edge-falling";
else
trigger = "edge-undefined";
wake = !!(nmk_chip->real_wake & BIT(offset));
seq_printf(s, " irq-%d %s%s",
irq, trigger, wake ? " wakeup" : "");
}
}
clk_disable(nmk_chip->clk);
}
static void nmk_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
unsigned int i, gpio = chip->base;
for (i = 0; i < chip->ngpio; i++, gpio++) {
nmk_gpio_dbg_show_one(s, NULL, chip, i, gpio);
seq_puts(s, "\n");
}
}
#else
#define nmk_gpio_dbg_show NULL
#endif
/*
* We will allocate memory for the state container using devm* allocators
* binding to the first device reaching this point, it doesn't matter if
* it is the pin controller or GPIO driver. However we need to use the right
* platform device when looking up resources so pay attention to pdev.
*/
struct nmk_gpio_chip *nmk_gpio_populate_chip(struct fwnode_handle *fwnode,
struct platform_device *pdev)
{
struct nmk_gpio_chip *nmk_chip;
struct platform_device *gpio_pdev;
struct device *dev = &pdev->dev;
struct reset_control *reset;
struct device *gpio_dev;
struct gpio_chip *chip;
struct resource *res;
struct clk *clk;
void __iomem *base;
u32 id, ngpio;
int ret;
gpio_dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
if (!gpio_dev) {
dev_err(dev, "populate \"%pfwP\": device not found\n", fwnode);
return ERR_PTR(-ENODEV);
}
gpio_pdev = to_platform_device(gpio_dev);
if (device_property_read_u32(gpio_dev, "gpio-bank", &id)) {
dev_err(dev, "populate: gpio-bank property not found\n");
platform_device_put(gpio_pdev);
return ERR_PTR(-EINVAL);
}
#ifdef CONFIG_PINCTRL_NOMADIK
if (id >= ARRAY_SIZE(nmk_gpio_chips)) {
dev_err(dev, "populate: invalid id: %u\n", id);
platform_device_put(gpio_pdev);
return ERR_PTR(-EINVAL);
}
/* Already populated? */
nmk_chip = nmk_gpio_chips[id];
if (nmk_chip) {
platform_device_put(gpio_pdev);
return nmk_chip;
}
#endif
nmk_chip = devm_kzalloc(dev, sizeof(*nmk_chip), GFP_KERNEL);
if (!nmk_chip) {
platform_device_put(gpio_pdev);
return ERR_PTR(-ENOMEM);
}
if (device_property_read_u32(gpio_dev, "ngpios", &ngpio)) {
ngpio = NMK_GPIO_PER_CHIP;
dev_dbg(dev, "populate: using default ngpio (%u)\n", ngpio);
}
nmk_chip->is_mobileye_soc = device_is_compatible(gpio_dev,
"mobileye,eyeq5-gpio");
nmk_chip->bank = id;
chip = &nmk_chip->chip;
chip->base = -1;
chip->ngpio = ngpio;
chip->label = dev_name(gpio_dev);
chip->parent = gpio_dev;
/* NOTE: different devices! No devm_platform_ioremap_resource() here! */
res = platform_get_resource(gpio_pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base)) {
platform_device_put(gpio_pdev);
return ERR_CAST(base);
}
nmk_chip->addr = base;
/* NOTE: do not use devm_ here! */
clk = clk_get_optional(gpio_dev, NULL);
if (IS_ERR(clk)) {
platform_device_put(gpio_pdev);
return ERR_CAST(clk);
}
clk_prepare(clk);
nmk_chip->clk = clk;
/* NOTE: do not use devm_ here! */
reset = reset_control_get_optional_shared(gpio_dev, NULL);
if (IS_ERR(reset)) {
clk_unprepare(clk);
clk_put(clk);
platform_device_put(gpio_pdev);
dev_err(dev, "failed getting reset control: %pe\n",
reset);
return ERR_CAST(reset);
}
/*
* Reset might be shared and asserts/deasserts calls are unbalanced. We
* only support sharing this reset with other gpio-nomadik devices that
* use this reset to ensure deassertion at probe.
*/
ret = reset_control_deassert(reset);
if (ret) {
reset_control_put(reset);
clk_unprepare(clk);
clk_put(clk);
platform_device_put(gpio_pdev);
dev_err(dev, "failed reset deassert: %d\n", ret);
return ERR_PTR(ret);
}
#ifdef CONFIG_PINCTRL_NOMADIK
nmk_gpio_chips[id] = nmk_chip;
#endif
return nmk_chip;
}
static void nmk_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
seq_printf(p, "nmk%u-%u-%u", nmk_chip->bank,
gc->base, gc->base + gc->ngpio - 1);
}
static const struct irq_chip nmk_irq_chip = {
.irq_ack = nmk_gpio_irq_ack,
.irq_mask = nmk_gpio_irq_mask,
.irq_unmask = nmk_gpio_irq_unmask,
.irq_set_type = nmk_gpio_irq_set_type,
.irq_set_wake = nmk_gpio_irq_set_wake,
.irq_startup = nmk_gpio_irq_startup,
.irq_shutdown = nmk_gpio_irq_shutdown,
.irq_print_chip = nmk_gpio_irq_print_chip,
.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static int nmk_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct nmk_gpio_chip *nmk_chip;
struct gpio_irq_chip *girq;
bool supports_sleepmode;
struct gpio_chip *chip;
int irq;
int ret;
nmk_chip = nmk_gpio_populate_chip(dev_fwnode(dev), pdev);
if (IS_ERR(nmk_chip)) {
dev_err(dev, "could not populate nmk chip struct\n");
return PTR_ERR(nmk_chip);
}
supports_sleepmode =
device_property_read_bool(dev, "st,supports-sleepmode");
/* Correct platform device ID */
pdev->id = nmk_chip->bank;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
/*
* The virt address in nmk_chip->addr is in the nomadik register space,
* so we can simply convert the resource address, without remapping
*/
nmk_chip->sleepmode = supports_sleepmode;
spin_lock_init(&nmk_chip->lock);
chip = &nmk_chip->chip;
chip->parent = dev;
chip->request = gpiochip_generic_request;
chip->free = gpiochip_generic_free;
chip->get_direction = nmk_gpio_get_dir;
chip->direction_input = nmk_gpio_make_input;
chip->get = nmk_gpio_get_input;
chip->direction_output = nmk_gpio_make_output;
chip->set = nmk_gpio_set_output;
chip->dbg_show = nmk_gpio_dbg_show;
chip->can_sleep = false;
chip->owner = THIS_MODULE;
girq = &chip->irq;
gpio_irq_chip_set_chip(girq, &nmk_irq_chip);
girq->parent_handler = NULL;
girq->num_parents = 0;
girq->parents = NULL;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_edge_irq;
ret = devm_request_irq(dev, irq, nmk_gpio_irq_handler, IRQF_SHARED,
dev_name(dev), nmk_chip);
if (ret) {
dev_err(dev, "failed requesting IRQ\n");
return ret;
}
if (!nmk_chip->is_mobileye_soc) {
clk_enable(nmk_chip->clk);
nmk_chip->lowemi = readl_relaxed(nmk_chip->addr + NMK_GPIO_LOWEMI);
clk_disable(nmk_chip->clk);
}
ret = gpiochip_add_data(chip, nmk_chip);
if (ret)
return ret;
platform_set_drvdata(pdev, nmk_chip);
dev_info(dev, "chip registered\n");
return 0;
}
static const struct of_device_id nmk_gpio_match[] = {
{ .compatible = "st,nomadik-gpio", },
{ .compatible = "mobileye,eyeq5-gpio", },
{}
};
static struct platform_driver nmk_gpio_driver = {
.driver = {
.name = "nomadik-gpio",
.of_match_table = nmk_gpio_match,
.suppress_bind_attrs = true,
},
.probe = nmk_gpio_probe,
};
static int __init nmk_gpio_init(void)
{
return platform_driver_register(&nmk_gpio_driver);
}
subsys_initcall(nmk_gpio_init);