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Diffstat (limited to 'arch/sh/boards/mach-x3proto/gpio.c')
-rw-r--r--arch/sh/boards/mach-x3proto/gpio.c136
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..f82d3a6a8
--- /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_domain_irq(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;
+}