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path: root/arch/mips/jz4740/gpio.c
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Diffstat (limited to 'arch/mips/jz4740/gpio.c')
-rw-r--r--arch/mips/jz4740/gpio.c604
1 files changed, 604 insertions, 0 deletions
diff --git a/arch/mips/jz4740/gpio.c b/arch/mips/jz4740/gpio.c
new file mode 100644
index 00000000000..38f60f35156
--- /dev/null
+++ b/arch/mips/jz4740/gpio.c
@@ -0,0 +1,604 @@
+/*
+ * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
+ * JZ4740 platform GPIO support
+ *
+ * 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.
+ *
+ * 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.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/spinlock.h>
+#include <linux/sysdev.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include <asm/mach-jz4740/base.h>
+
+#define JZ4740_GPIO_BASE_A (32*0)
+#define JZ4740_GPIO_BASE_B (32*1)
+#define JZ4740_GPIO_BASE_C (32*2)
+#define JZ4740_GPIO_BASE_D (32*3)
+
+#define JZ4740_GPIO_NUM_A 32
+#define JZ4740_GPIO_NUM_B 32
+#define JZ4740_GPIO_NUM_C 31
+#define JZ4740_GPIO_NUM_D 32
+
+#define JZ4740_IRQ_GPIO_BASE_A (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_A)
+#define JZ4740_IRQ_GPIO_BASE_B (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_B)
+#define JZ4740_IRQ_GPIO_BASE_C (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_C)
+#define JZ4740_IRQ_GPIO_BASE_D (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_D)
+
+#define JZ_REG_GPIO_PIN 0x00
+#define JZ_REG_GPIO_DATA 0x10
+#define JZ_REG_GPIO_DATA_SET 0x14
+#define JZ_REG_GPIO_DATA_CLEAR 0x18
+#define JZ_REG_GPIO_MASK 0x20
+#define JZ_REG_GPIO_MASK_SET 0x24
+#define JZ_REG_GPIO_MASK_CLEAR 0x28
+#define JZ_REG_GPIO_PULL 0x30
+#define JZ_REG_GPIO_PULL_SET 0x34
+#define JZ_REG_GPIO_PULL_CLEAR 0x38
+#define JZ_REG_GPIO_FUNC 0x40
+#define JZ_REG_GPIO_FUNC_SET 0x44
+#define JZ_REG_GPIO_FUNC_CLEAR 0x48
+#define JZ_REG_GPIO_SELECT 0x50
+#define JZ_REG_GPIO_SELECT_SET 0x54
+#define JZ_REG_GPIO_SELECT_CLEAR 0x58
+#define JZ_REG_GPIO_DIRECTION 0x60
+#define JZ_REG_GPIO_DIRECTION_SET 0x64
+#define JZ_REG_GPIO_DIRECTION_CLEAR 0x68
+#define JZ_REG_GPIO_TRIGGER 0x70
+#define JZ_REG_GPIO_TRIGGER_SET 0x74
+#define JZ_REG_GPIO_TRIGGER_CLEAR 0x78
+#define JZ_REG_GPIO_FLAG 0x80
+#define JZ_REG_GPIO_FLAG_CLEAR 0x14
+
+#define GPIO_TO_BIT(gpio) BIT(gpio & 0x1f)
+#define GPIO_TO_REG(gpio, reg) (gpio_to_jz_gpio_chip(gpio)->base + (reg))
+#define CHIP_TO_REG(chip, reg) (gpio_chip_to_jz_gpio_chip(chip)->base + (reg))
+
+struct jz_gpio_chip {
+ unsigned int irq;
+ unsigned int irq_base;
+ uint32_t wakeup;
+ uint32_t suspend_mask;
+ uint32_t edge_trigger_both;
+
+ void __iomem *base;
+
+ spinlock_t lock;
+
+ struct gpio_chip gpio_chip;
+ struct irq_chip irq_chip;
+ struct sys_device sysdev;
+};
+
+static struct jz_gpio_chip jz4740_gpio_chips[];
+
+static inline struct jz_gpio_chip *gpio_to_jz_gpio_chip(unsigned int gpio)
+{
+ return &jz4740_gpio_chips[gpio >> 5];
+}
+
+static inline struct jz_gpio_chip *gpio_chip_to_jz_gpio_chip(struct gpio_chip *gpio_chip)
+{
+ return container_of(gpio_chip, struct jz_gpio_chip, gpio_chip);
+}
+
+static inline struct jz_gpio_chip *irq_to_jz_gpio_chip(unsigned int irq)
+{
+ return get_irq_chip_data(irq);
+}
+
+static inline void jz_gpio_write_bit(unsigned int gpio, unsigned int reg)
+{
+ writel(GPIO_TO_BIT(gpio), GPIO_TO_REG(gpio, reg));
+}
+
+int jz_gpio_set_function(int gpio, enum jz_gpio_function function)
+{
+ if (function == JZ_GPIO_FUNC_NONE) {
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_CLEAR);
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
+ } else {
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_SET);
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
+ switch (function) {
+ case JZ_GPIO_FUNC1:
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
+ break;
+ case JZ_GPIO_FUNC3:
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_SET);
+ case JZ_GPIO_FUNC2: /* Falltrough */
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_SET);
+ break;
+ default:
+ BUG();
+ break;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(jz_gpio_set_function);
+
+int jz_gpio_bulk_request(const struct jz_gpio_bulk_request *request, size_t num)
+{
+ size_t i;
+ int ret;
+
+ for (i = 0; i < num; ++i, ++request) {
+ ret = gpio_request(request->gpio, request->name);
+ if (ret)
+ goto err;
+ jz_gpio_set_function(request->gpio, request->function);
+ }
+
+ return 0;
+
+err:
+ for (--request; i > 0; --i, --request) {
+ gpio_free(request->gpio);
+ jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(jz_gpio_bulk_request);
+
+void jz_gpio_bulk_free(const struct jz_gpio_bulk_request *request, size_t num)
+{
+ size_t i;
+
+ for (i = 0; i < num; ++i, ++request) {
+ gpio_free(request->gpio);
+ jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
+ }
+
+}
+EXPORT_SYMBOL_GPL(jz_gpio_bulk_free);
+
+void jz_gpio_bulk_suspend(const struct jz_gpio_bulk_request *request, size_t num)
+{
+ size_t i;
+
+ for (i = 0; i < num; ++i, ++request) {
+ jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
+ jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_DIRECTION_CLEAR);
+ jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_PULL_SET);
+ }
+}
+EXPORT_SYMBOL_GPL(jz_gpio_bulk_suspend);
+
+void jz_gpio_bulk_resume(const struct jz_gpio_bulk_request *request, size_t num)
+{
+ size_t i;
+
+ for (i = 0; i < num; ++i, ++request)
+ jz_gpio_set_function(request->gpio, request->function);
+}
+EXPORT_SYMBOL_GPL(jz_gpio_bulk_resume);
+
+void jz_gpio_enable_pullup(unsigned gpio)
+{
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_CLEAR);
+}
+EXPORT_SYMBOL_GPL(jz_gpio_enable_pullup);
+
+void jz_gpio_disable_pullup(unsigned gpio)
+{
+ jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_SET);
+}
+EXPORT_SYMBOL_GPL(jz_gpio_disable_pullup);
+
+static int jz_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+ return !!(readl(CHIP_TO_REG(chip, JZ_REG_GPIO_PIN)) & BIT(gpio));
+}
+
+static void jz_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
+{
+ uint32_t __iomem *reg = CHIP_TO_REG(chip, JZ_REG_GPIO_DATA_SET);
+ reg += !value;
+ writel(BIT(gpio), reg);
+}
+
+static int jz_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
+ int value)
+{
+ writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_SET));
+ jz_gpio_set_value(chip, gpio, value);
+
+ return 0;
+}
+
+static int jz_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+ writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_CLEAR));
+
+ return 0;
+}
+
+int jz_gpio_port_direction_input(int port, uint32_t mask)
+{
+ writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_CLEAR));
+
+ return 0;
+}
+EXPORT_SYMBOL(jz_gpio_port_direction_input);
+
+int jz_gpio_port_direction_output(int port, uint32_t mask)
+{
+ writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_SET));
+
+ return 0;
+}
+EXPORT_SYMBOL(jz_gpio_port_direction_output);
+
+void jz_gpio_port_set_value(int port, uint32_t value, uint32_t mask)
+{
+ writel(~value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_CLEAR));
+ writel(value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_SET));
+}
+EXPORT_SYMBOL(jz_gpio_port_set_value);
+
+uint32_t jz_gpio_port_get_value(int port, uint32_t mask)
+{
+ uint32_t value = readl(GPIO_TO_REG(port, JZ_REG_GPIO_PIN));
+
+ return value & mask;
+}
+EXPORT_SYMBOL(jz_gpio_port_get_value);
+
+int gpio_to_irq(unsigned gpio)
+{
+ return JZ4740_IRQ_GPIO(0) + gpio;
+}
+EXPORT_SYMBOL_GPL(gpio_to_irq);
+
+int irq_to_gpio(unsigned irq)
+{
+ return irq - JZ4740_IRQ_GPIO(0);
+}
+EXPORT_SYMBOL_GPL(irq_to_gpio);
+
+#define IRQ_TO_BIT(irq) BIT(irq_to_gpio(irq) & 0x1f)
+
+static void jz_gpio_check_trigger_both(struct jz_gpio_chip *chip, unsigned int irq)
+{
+ uint32_t value;
+ void __iomem *reg;
+ uint32_t mask = IRQ_TO_BIT(irq);
+
+ if (!(chip->edge_trigger_both & mask))
+ return;
+
+ reg = chip->base;
+
+ value = readl(chip->base + JZ_REG_GPIO_PIN);
+ if (value & mask)
+ reg += JZ_REG_GPIO_DIRECTION_CLEAR;
+ else
+ reg += JZ_REG_GPIO_DIRECTION_SET;
+
+ writel(mask, reg);
+}
+
+static void jz_gpio_irq_demux_handler(unsigned int irq, struct irq_desc *desc)
+{
+ uint32_t flag;
+ unsigned int gpio_irq;
+ unsigned int gpio_bank;
+ struct jz_gpio_chip *chip = get_irq_desc_data(desc);
+
+ gpio_bank = JZ4740_IRQ_GPIO0 - irq;
+
+ flag = readl(chip->base + JZ_REG_GPIO_FLAG);
+
+ if (!flag)
+ return;
+
+ gpio_irq = __fls(flag);
+
+ jz_gpio_check_trigger_both(chip, irq);
+
+ gpio_irq += (gpio_bank << 5) + JZ4740_IRQ_GPIO(0);
+
+ generic_handle_irq(gpio_irq);
+};
+
+static inline void jz_gpio_set_irq_bit(unsigned int irq, unsigned int reg)
+{
+ struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
+ writel(IRQ_TO_BIT(irq), chip->base + reg);
+}
+
+static void jz_gpio_irq_mask(unsigned int irq)
+{
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_SET);
+};
+
+static void jz_gpio_irq_unmask(unsigned int irq)
+{
+ struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
+
+ jz_gpio_check_trigger_both(chip, irq);
+
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_CLEAR);
+};
+
+/* TODO: Check if function is gpio */
+static unsigned int jz_gpio_irq_startup(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_SET);
+
+ desc->status &= ~IRQ_MASKED;
+ jz_gpio_irq_unmask(irq);
+
+ return 0;
+}
+
+static void jz_gpio_irq_shutdown(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ jz_gpio_irq_mask(irq);
+ desc->status |= IRQ_MASKED;
+
+ /* Set direction to input */
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_CLEAR);
+}
+
+static void jz_gpio_irq_ack(unsigned int irq)
+{
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_FLAG_CLEAR);
+};
+
+static int jz_gpio_irq_set_type(unsigned int irq, unsigned int flow_type)
+{
+ struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ jz_gpio_irq_mask(irq);
+
+ if (flow_type == IRQ_TYPE_EDGE_BOTH) {
+ uint32_t value = readl(chip->base + JZ_REG_GPIO_PIN);
+ if (value & IRQ_TO_BIT(irq))
+ flow_type = IRQ_TYPE_EDGE_FALLING;
+ else
+ flow_type = IRQ_TYPE_EDGE_RISING;
+ chip->edge_trigger_both |= IRQ_TO_BIT(irq);
+ } else {
+ chip->edge_trigger_both &= ~IRQ_TO_BIT(irq);
+ }
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
+ jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (!(desc->status & IRQ_MASKED))
+ jz_gpio_irq_unmask(irq);
+
+ return 0;
+}
+
+static int jz_gpio_irq_set_wake(unsigned int irq, unsigned int on)
+{
+ struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
+ spin_lock(&chip->lock);
+ if (on)
+ chip->wakeup |= IRQ_TO_BIT(irq);
+ else
+ chip->wakeup &= ~IRQ_TO_BIT(irq);
+ spin_unlock(&chip->lock);
+
+ set_irq_wake(chip->irq, on);
+ return 0;
+}
+
+/*
+ * This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+static struct lock_class_key gpio_lock_class;
+
+#define JZ4740_GPIO_CHIP(_bank) { \
+ .irq_base = JZ4740_IRQ_GPIO_BASE_ ## _bank, \
+ .gpio_chip = { \
+ .label = "Bank " # _bank, \
+ .owner = THIS_MODULE, \
+ .set = jz_gpio_set_value, \
+ .get = jz_gpio_get_value, \
+ .direction_output = jz_gpio_direction_output, \
+ .direction_input = jz_gpio_direction_input, \
+ .base = JZ4740_GPIO_BASE_ ## _bank, \
+ .ngpio = JZ4740_GPIO_NUM_ ## _bank, \
+ }, \
+ .irq_chip = { \
+ .name = "GPIO Bank " # _bank, \
+ .mask = jz_gpio_irq_mask, \
+ .unmask = jz_gpio_irq_unmask, \
+ .ack = jz_gpio_irq_ack, \
+ .startup = jz_gpio_irq_startup, \
+ .shutdown = jz_gpio_irq_shutdown, \
+ .set_type = jz_gpio_irq_set_type, \
+ .set_wake = jz_gpio_irq_set_wake, \
+ }, \
+}
+
+static struct jz_gpio_chip jz4740_gpio_chips[] = {
+ JZ4740_GPIO_CHIP(A),
+ JZ4740_GPIO_CHIP(B),
+ JZ4740_GPIO_CHIP(C),
+ JZ4740_GPIO_CHIP(D),
+};
+
+static inline struct jz_gpio_chip *sysdev_to_chip(struct sys_device *dev)
+{
+ return container_of(dev, struct jz_gpio_chip, sysdev);
+}
+
+static int jz4740_gpio_suspend(struct sys_device *dev, pm_message_t state)
+{
+ struct jz_gpio_chip *chip = sysdev_to_chip(dev);
+
+ chip->suspend_mask = readl(chip->base + JZ_REG_GPIO_MASK);
+ writel(~(chip->wakeup), chip->base + JZ_REG_GPIO_MASK_SET);
+ writel(chip->wakeup, chip->base + JZ_REG_GPIO_MASK_CLEAR);
+
+ return 0;
+}
+
+static int jz4740_gpio_resume(struct sys_device *dev)
+{
+ struct jz_gpio_chip *chip = sysdev_to_chip(dev);
+ uint32_t mask = chip->suspend_mask;
+
+ writel(~mask, chip->base + JZ_REG_GPIO_MASK_CLEAR);
+ writel(mask, chip->base + JZ_REG_GPIO_MASK_SET);
+
+ return 0;
+}
+
+static struct sysdev_class jz4740_gpio_sysdev_class = {
+ .name = "gpio",
+ .suspend = jz4740_gpio_suspend,
+ .resume = jz4740_gpio_resume,
+};
+
+static int jz4740_gpio_chip_init(struct jz_gpio_chip *chip, unsigned int id)
+{
+ int ret, irq;
+
+ chip->sysdev.id = id;
+ chip->sysdev.cls = &jz4740_gpio_sysdev_class;
+ ret = sysdev_register(&chip->sysdev);
+
+ if (ret)
+ return ret;
+
+ spin_lock_init(&chip->lock);
+
+ chip->base = ioremap(JZ4740_GPIO_BASE_ADDR + (id * 0x100), 0x100);
+
+ gpiochip_add(&chip->gpio_chip);
+
+ chip->irq = JZ4740_IRQ_INTC_GPIO(id);
+ set_irq_data(chip->irq, chip);
+ set_irq_chained_handler(chip->irq, jz_gpio_irq_demux_handler);
+
+ for (irq = chip->irq_base; irq < chip->irq_base + chip->gpio_chip.ngpio; ++irq) {
+ lockdep_set_class(&irq_desc[irq].lock, &gpio_lock_class);
+ set_irq_chip_data(irq, chip);
+ set_irq_chip_and_handler(irq, &chip->irq_chip, handle_level_irq);
+ }
+
+ return 0;
+}
+
+static int __init jz4740_gpio_init(void)
+{
+ unsigned int i;
+ int ret;
+
+ ret = sysdev_class_register(&jz4740_gpio_sysdev_class);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i)
+ jz4740_gpio_chip_init(&jz4740_gpio_chips[i], i);
+
+ printk(KERN_INFO "JZ4740 GPIO initalized\n");
+
+ return 0;
+}
+arch_initcall(jz4740_gpio_init);
+
+#ifdef CONFIG_DEBUG_FS
+
+static inline void gpio_seq_reg(struct seq_file *s, struct jz_gpio_chip *chip,
+ const char *name, unsigned int reg)
+{
+ seq_printf(s, "\t%s: %08x\n", name, readl(chip->base + reg));
+}
+
+static int gpio_regs_show(struct seq_file *s, void *unused)
+{
+ struct jz_gpio_chip *chip = jz4740_gpio_chips;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i, ++chip) {
+ seq_printf(s, "==GPIO %d==\n", i);
+ gpio_seq_reg(s, chip, "Pin", JZ_REG_GPIO_PIN);
+ gpio_seq_reg(s, chip, "Data", JZ_REG_GPIO_DATA);
+ gpio_seq_reg(s, chip, "Mask", JZ_REG_GPIO_MASK);
+ gpio_seq_reg(s, chip, "Pull", JZ_REG_GPIO_PULL);
+ gpio_seq_reg(s, chip, "Func", JZ_REG_GPIO_FUNC);
+ gpio_seq_reg(s, chip, "Select", JZ_REG_GPIO_SELECT);
+ gpio_seq_reg(s, chip, "Direction", JZ_REG_GPIO_DIRECTION);
+ gpio_seq_reg(s, chip, "Trigger", JZ_REG_GPIO_TRIGGER);
+ gpio_seq_reg(s, chip, "Flag", JZ_REG_GPIO_FLAG);
+ }
+
+ return 0;
+}
+
+static int gpio_regs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, gpio_regs_show, NULL);
+}
+
+static const struct file_operations gpio_regs_operations = {
+ .open = gpio_regs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init gpio_debugfs_init(void)
+{
+ (void) debugfs_create_file("jz_regs_gpio", S_IFREG | S_IRUGO,
+ NULL, NULL, &gpio_regs_operations);
+ return 0;
+}
+subsys_initcall(gpio_debugfs_init);
+
+#endif