gpio/ep93xx: move driver to drivers/gpio

The GPIO driver should reside in drivers/gpio.

v3: Change Kconfig option to def_bool y
v2: Make the Kconfig symbol a silent option, dependent on ARCH_EP93XX

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 410 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-ep93xx.c b/drivers/gpio/gpio-ep93xx.c
new file mode 100644
index 00000000000..415dce37b88
--- /dev/null
+++ b/drivers/gpio/gpio-ep93xx.c
@@ -0,0 +1,410 @@
+/*
+ * 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.
+ */
+
+#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+
+#include <mach/hardware.h>
+
+/*************************************************************************
+ * Interrupt handling for EP93xx on-chip GPIOs
+ *************************************************************************/
+static unsigned char gpio_int_unmasked[3];
+static unsigned char gpio_int_enabled[3];
+static unsigned char gpio_int_type1[3];
+static unsigned char gpio_int_type2[3];
+static unsigned char gpio_int_debounce[3];
+
+/* Port ordering is: A B F */
+static const u8 int_type1_register_offset[3]	= { 0x90, 0xac, 0x4c };
+static const u8 int_type2_register_offset[3]	= { 0x94, 0xb0, 0x50 };
+static const u8 eoi_register_offset[3]		= { 0x98, 0xb4, 0x54 };
+static const u8 int_en_register_offset[3]	= { 0x9c, 0xb8, 0x58 };
+static const u8 int_debounce_register_offset[3]	= { 0xa8, 0xc4, 0x64 };
+
+static void ep93xx_gpio_update_int_params(unsigned port)
+{
+	BUG_ON(port > 2);
+
+	__raw_writeb(0, EP93XX_GPIO_REG(int_en_register_offset[port]));
+
+	__raw_writeb(gpio_int_type2[port],
+		EP93XX_GPIO_REG(int_type2_register_offset[port]));
+
+	__raw_writeb(gpio_int_type1[port],
+		EP93XX_GPIO_REG(int_type1_register_offset[port]));
+
+	__raw_writeb(gpio_int_unmasked[port] & gpio_int_enabled[port],
+		EP93XX_GPIO_REG(int_en_register_offset[port]));
+}
+
+static inline void ep93xx_gpio_int_mask(unsigned line)
+{
+	gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7));
+}
+
+static void ep93xx_gpio_int_debounce(unsigned int irq, bool enable)
+{
+	int line = irq_to_gpio(irq);
+	int port = line >> 3;
+	int port_mask = 1 << (line & 7);
+
+	if (enable)
+		gpio_int_debounce[port] |= port_mask;
+	else
+		gpio_int_debounce[port] &= ~port_mask;
+
+	__raw_writeb(gpio_int_debounce[port],
+		EP93XX_GPIO_REG(int_debounce_register_offset[port]));
+}
+
+static void ep93xx_gpio_ab_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned char status;
+	int i;
+
+	status = __raw_readb(EP93XX_GPIO_A_INT_STATUS);
+	for (i = 0; i < 8; i++) {
+		if (status & (1 << i)) {
+			int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_A(0)) + i;
+			generic_handle_irq(gpio_irq);
+		}
+	}
+
+	status = __raw_readb(EP93XX_GPIO_B_INT_STATUS);
+	for (i = 0; i < 8; i++) {
+		if (status & (1 << i)) {
+			int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_B(0)) + i;
+			generic_handle_irq(gpio_irq);
+		}
+	}
+}
+
+static void ep93xx_gpio_f_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	/*
+	 * map discontiguous hw irq range to continuous sw irq range:
+	 *
+	 *  IRQ_EP93XX_GPIO{0..7}MUX -> gpio_to_irq(EP93XX_GPIO_LINE_F({0..7})
+	 */
+	int port_f_idx = ((irq + 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */
+	int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_F(0)) + port_f_idx;
+
+	generic_handle_irq(gpio_irq);
+}
+
+static void ep93xx_gpio_irq_ack(struct irq_data *d)
+{
+	int line = irq_to_gpio(d->irq);
+	int port = line >> 3;
+	int port_mask = 1 << (line & 7);
+
+	if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) {
+		gpio_int_type2[port] ^= port_mask; /* switch edge direction */
+		ep93xx_gpio_update_int_params(port);
+	}
+
+	__raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port]));
+}
+
+static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
+{
+	int line = irq_to_gpio(d->irq);
+	int port = line >> 3;
+	int port_mask = 1 << (line & 7);
+
+	if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH)
+		gpio_int_type2[port] ^= port_mask; /* switch edge direction */
+
+	gpio_int_unmasked[port] &= ~port_mask;
+	ep93xx_gpio_update_int_params(port);
+
+	__raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port]));
+}
+
+static void ep93xx_gpio_irq_mask(struct irq_data *d)
+{
+	int line = irq_to_gpio(d->irq);
+	int port = line >> 3;
+
+	gpio_int_unmasked[port] &= ~(1 << (line & 7));
+	ep93xx_gpio_update_int_params(port);
+}
+
+static void ep93xx_gpio_irq_unmask(struct irq_data *d)
+{
+	int line = irq_to_gpio(d->irq);
+	int port = line >> 3;
+
+	gpio_int_unmasked[port] |= 1 << (line & 7);
+	ep93xx_gpio_update_int_params(port);
+}
+
+/*
+ * gpio_int_type1 controls whether the interrupt is level (0) or
+ * edge (1) triggered, while gpio_int_type2 controls whether it
+ * triggers on low/falling (0) or high/rising (1).
+ */
+static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)
+{
+	const int gpio = irq_to_gpio(d->irq);
+	const int port = gpio >> 3;
+	const int port_mask = 1 << (gpio & 7);
+	irq_flow_handler_t handler;
+
+	gpio_direction_input(gpio);
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		gpio_int_type1[port] |= port_mask;
+		gpio_int_type2[port] |= port_mask;
+		handler = handle_edge_irq;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		gpio_int_type1[port] |= port_mask;
+		gpio_int_type2[port] &= ~port_mask;
+		handler = handle_edge_irq;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		gpio_int_type1[port] &= ~port_mask;
+		gpio_int_type2[port] |= port_mask;
+		handler = handle_level_irq;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		gpio_int_type1[port] &= ~port_mask;
+		gpio_int_type2[port] &= ~port_mask;
+		handler = handle_level_irq;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		gpio_int_type1[port] |= port_mask;
+		/* set initial polarity based on current input level */
+		if (gpio_get_value(gpio))
+			gpio_int_type2[port] &= ~port_mask; /* falling */
+		else
+			gpio_int_type2[port] |= port_mask; /* rising */
+		handler = handle_edge_irq;
+		break;
+	default:
+		pr_err("failed to set irq type %d for gpio %d\n", type, gpio);
+		return -EINVAL;
+	}
+
+	__irq_set_handler_locked(d->irq, handler);
+
+	gpio_int_enabled[port] |= port_mask;
+
+	ep93xx_gpio_update_int_params(port);
+
+	return 0;
+}
+
+static struct irq_chip ep93xx_gpio_irq_chip = {
+	.name		= "GPIO",
+	.irq_ack	= ep93xx_gpio_irq_ack,
+	.irq_mask_ack	= ep93xx_gpio_irq_mask_ack,
+	.irq_mask	= ep93xx_gpio_irq_mask,
+	.irq_unmask	= ep93xx_gpio_irq_unmask,
+	.irq_set_type	= ep93xx_gpio_irq_type,
+};
+
+void __init ep93xx_gpio_init_irq(void)
+{
+	int gpio_irq;
+
+	for (gpio_irq = gpio_to_irq(0);
+	     gpio_irq <= gpio_to_irq(EP93XX_GPIO_LINE_MAX_IRQ); ++gpio_irq) {
+		irq_set_chip_and_handler(gpio_irq, &ep93xx_gpio_irq_chip,
+					 handle_level_irq);
+		set_irq_flags(gpio_irq, IRQF_VALID);
+	}
+
+	irq_set_chained_handler(IRQ_EP93XX_GPIO_AB,
+				ep93xx_gpio_ab_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO0MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO1MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO2MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO3MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO4MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO5MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO6MUX,
+				ep93xx_gpio_f_irq_handler);
+	irq_set_chained_handler(IRQ_EP93XX_GPIO7MUX,
+				ep93xx_gpio_f_irq_handler);
+}
+
+
+/*************************************************************************
+ * gpiolib interface for EP93xx on-chip GPIOs
+ *************************************************************************/
+struct ep93xx_gpio_chip {
+	struct gpio_chip	chip;
+
+	void __iomem		*data_reg;
+	void __iomem		*data_dir_reg;
+};
+
+#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip)
+
+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 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 (irq < 0)
+		return -EINVAL;
+
+	ep93xx_gpio_int_debounce(irq, debounce ? true : false);
+
+	return 0;
+}
+
+#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),			\
+	}
+
+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;
+
+	/* 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);
+
+	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);
+	}
+}