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-rw-r--r--arch/arm/mach-ep93xx/gpio.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/arch/arm/mach-ep93xx/gpio.c b/arch/arm/mach-ep93xx/gpio.c
new file mode 100644
index 0000000..482cf3d
--- /dev/null
+++ b/arch/arm/mach-ep93xx/gpio.c
@@ -0,0 +1,158 @@
+/*
+ * linux/arch/arm/mach-ep93xx/gpio.c
+ *
+ * Generic EP93xx GPIO handling
+ *
+ * Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com>
+ *
+ * Based on code originally from:
+ * linux/arch/arm/mach-ep93xx/core.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/io.h>
+
+#include <mach/ep93xx-regs.h>
+#include <asm/gpio.h>
+
+struct ep93xx_gpio_chip {
+ struct gpio_chip chip;
+
+ unsigned int data_reg;
+ unsigned int data_dir_reg;
+};
+
+#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip)
+
+/* From core.c */
+extern void ep93xx_gpio_int_mask(unsigned line);
+extern void ep93xx_gpio_update_int_params(unsigned port);
+
+static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ 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_dir_reg);
+ v &= ~(1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_dir_reg);
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int ep93xx_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int val)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+ unsigned long flags;
+ int line;
+ u8 v;
+
+ local_irq_save(flags);
+
+ /* 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);
+ }
+
+ v = __raw_readb(ep93xx_chip->data_dir_reg);
+ v |= (1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_dir_reg);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int ep93xx_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+
+ return !!(__raw_readb(ep93xx_chip->data_reg) & (1 << offset));
+}
+
+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);
+}
+
+static void ep93xx_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+ u8 data_reg, data_dir_reg;
+ int i;
+
+ data_reg = __raw_readb(ep93xx_chip->data_reg);
+ data_dir_reg = __raw_readb(ep93xx_chip->data_dir_reg);
+
+ for (i = 0; i < chip->ngpio; i++)
+ seq_printf(s, "GPIO %s%d: %s %s\n", chip->label, i,
+ (data_reg & (1 << i)) ? "set" : "clear",
+ (data_dir_reg & (1 << i)) ? "out" : "in");
+}
+
+#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, \
+ .dbg_show = ep93xx_gpio_dbg_show, \
+ .base = base_gpio, \
+ .ngpio = 8, \
+ }, \
+ .data_reg = EP93XX_GPIO_REG(dr), \
+ .data_dir_reg = EP93XX_GPIO_REG(ddr), \
+ }
+
+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),
+};
+
+void __init ep93xx_gpio_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++)
+ gpiochip_add(&ep93xx_gpio_banks[i].chip);
+}
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