[ARM] 4988/1: Add GPIO lib support to the EP93xx

Adds support for the generic GPIO lib to the EP93xx family. The gpio
handling code has been moved from core.c to a new file called gpio.c.
The GPIO based IRQ code has not been changed.

Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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 000000000000..dc2e4c00d989
--- /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 <asm/arch/ep93xx-regs.h>
+#include <asm/io.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", 0x30, 0x34, 40),
+	EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24),
+	EP93XX_GPIO_BANK("E", 0x20, 0x24, 32),
+	EP93XX_GPIO_BANK("F", 0x08, 0x18, 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);
+}