1 files changed, 136 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-x3proto/gpio.c b/arch/sh/boards/mach-x3proto/gpio.c
new file mode 100644
index 000000000..efc992f64
--- /dev/null
+++ b/arch/sh/boards/mach-x3proto/gpio.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/boards/mach-x3proto/gpio.c
+ *
+ * Renesas SH-X3 Prototype Baseboard GPIO Support.
+ *
+ * Copyright (C) 2010 - 2012  Paul Mundt
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/gpio/driver.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <mach/ilsel.h>
+#include <mach/hardware.h>
+
+#define KEYCTLR	0xb81c0000
+#define KEYOUTR	0xb81c0002
+#define KEYDETR 0xb81c0004
+
+static DEFINE_SPINLOCK(x3proto_gpio_lock);
+static struct irq_domain *x3proto_irq_domain;
+
+static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+	unsigned long flags;
+	unsigned int data;
+
+	spin_lock_irqsave(&x3proto_gpio_lock, flags);
+	data = __raw_readw(KEYCTLR);
+	data |= (1 << gpio);
+	__raw_writew(data, KEYCTLR);
+	spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
+
+	return 0;
+}
+
+static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio)
+{
+	return !!(__raw_readw(KEYDETR) & (1 << gpio));
+}
+
+static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
+{
+	int virq;
+
+	if (gpio < chip->ngpio)
+		virq = irq_create_mapping(x3proto_irq_domain, gpio);
+	else
+		virq = -ENXIO;
+
+	return virq;
+}
+
+static void x3proto_gpio_irq_handler(struct irq_desc *desc)
+{
+	struct irq_data *data = irq_desc_get_irq_data(desc);
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	unsigned long mask;
+	int pin;
+
+	chip->irq_mask_ack(data);
+
+	mask = __raw_readw(KEYDETR);
+	for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)
+		generic_handle_irq(irq_linear_revmap(x3proto_irq_domain, pin));
+
+	chip->irq_unmask(data);
+}
+
+struct gpio_chip x3proto_gpio_chip = {
+	.label			= "x3proto-gpio",
+	.direction_input	= x3proto_gpio_direction_input,
+	.get			= x3proto_gpio_get,
+	.to_irq			= x3proto_gpio_to_irq,
+	.base			= -1,
+	.ngpio			= NR_BASEBOARD_GPIOS,
+};
+
+static int x3proto_gpio_irq_map(struct irq_domain *domain, unsigned int virq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler_name(virq, &dummy_irq_chip, handle_simple_irq,
+				      "gpio");
+
+	return 0;
+}
+
+static struct irq_domain_ops x3proto_gpio_irq_ops = {
+	.map	= x3proto_gpio_irq_map,
+	.xlate	= irq_domain_xlate_twocell,
+};
+
+int __init x3proto_gpio_setup(void)
+{
+	int ilsel, ret;
+
+	ilsel = ilsel_enable(ILSEL_KEY);
+	if (unlikely(ilsel < 0))
+		return ilsel;
+
+	ret = gpiochip_add_data(&x3proto_gpio_chip, NULL);
+	if (unlikely(ret))
+		goto err_gpio;
+
+	x3proto_irq_domain = irq_domain_add_linear(NULL, NR_BASEBOARD_GPIOS,
+						   &x3proto_gpio_irq_ops, NULL);
+	if (unlikely(!x3proto_irq_domain))
+		goto err_irq;
+
+	pr_info("registering '%s' support, handling GPIOs %u -> %u, "
+		"bound to IRQ %u\n",
+		x3proto_gpio_chip.label, x3proto_gpio_chip.base,
+		x3proto_gpio_chip.base + x3proto_gpio_chip.ngpio,
+		ilsel);
+
+	irq_set_chained_handler(ilsel, x3proto_gpio_irq_handler);
+	irq_set_irq_wake(ilsel, 1);
+
+	return 0;
+
+err_irq:
+	gpiochip_remove(&x3proto_gpio_chip);
+	ret = 0;
+err_gpio:
+	synchronize_irq(ilsel);
+
+	ilsel_disable(ILSEL_KEY);
+
+	return ret;
+}