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authorPaul Mundt <lethal@linux-sh.org>2010-10-04 02:59:29 +0900
committerPaul Mundt <lethal@linux-sh.org>2010-10-04 02:59:29 +0900
commit550591143eead286f2cd9d124a55d4a99ed024de (patch)
tree5f1edc1b8c8e0829f04a5d24b9083bd5a054c1fb /arch/sh/boards/mach-x3proto
parentd39d0ed196aa1685bb24771e92f78633c66ac9cb (diff)
sh: mach-x3proto: Support for baseboard GPIOs.
This adds trivial support for the GPIOs implemented through the baseboard CPLD, used for driving the button matrix. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/boards/mach-x3proto')
-rw-r--r--arch/sh/boards/mach-x3proto/Makefile2
-rw-r--r--arch/sh/boards/mach-x3proto/gpio.c135
2 files changed, 137 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-x3proto/Makefile b/arch/sh/boards/mach-x3proto/Makefile
index 983e4551fec..708c21c919f 100644
--- a/arch/sh/boards/mach-x3proto/Makefile
+++ b/arch/sh/boards/mach-x3proto/Makefile
@@ -1 +1,3 @@
obj-y += setup.o ilsel.o
+
+obj-$(CONFIG_GENERIC_GPIO) += gpio.o
diff --git a/arch/sh/boards/mach-x3proto/gpio.c b/arch/sh/boards/mach-x3proto/gpio.c
new file mode 100644
index 00000000000..9fcd7ce6aa4
--- /dev/null
+++ b/arch/sh/boards/mach-x3proto/gpio.c
@@ -0,0 +1,135 @@
+/*
+ * arch/sh/boards/mach-x3proto/gpio.c
+ *
+ * Renesas SH-X3 Prototype Baseboard GPIO Support.
+ *
+ * Copyright (C) 2010 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.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 unsigned int x3proto_gpio_irq_map[NR_BASEBOARD_GPIOS] = { 0, };
+
+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)
+{
+ return x3proto_gpio_irq_map[gpio];
+}
+
+static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+ struct irq_chip *chip = get_irq_desc_chip(desc);
+ unsigned long mask;
+ int pin;
+
+ chip->mask_ack(irq);
+
+ mask = __raw_readw(KEYDETR);
+
+ for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)
+ generic_handle_irq(x3proto_gpio_to_irq(NULL, pin));
+
+ chip->unmask(irq);
+}
+
+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,
+};
+
+int __init x3proto_gpio_setup(void)
+{
+ unsigned int ilsel;
+ int ret, i;
+
+ ilsel = ilsel_enable(ILSEL_KEY);
+ if (unlikely(ilsel < 0))
+ return ilsel;
+
+ ret = gpiochip_add(&x3proto_gpio_chip);
+ if (unlikely(ret))
+ goto err_gpio;
+
+ for (i = 0; i < NR_BASEBOARD_GPIOS; i++) {
+ unsigned long flags;
+ unsigned int irq = create_irq();
+
+ if (unlikely(irq < 0)) {
+ ret = -EINVAL;
+ goto err_irq;
+ }
+
+ spin_lock_irqsave(&x3proto_gpio_lock, flags);
+ x3proto_gpio_irq_map[i] = irq;
+ set_irq_chip_and_handler_name(irq, &dummy_irq_chip,
+ handle_simple_irq, "gpio");
+ spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
+ }
+
+ 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);
+
+ set_irq_chained_handler(ilsel, x3proto_gpio_irq_handler);
+ set_irq_wake(ilsel, 1);
+
+ return 0;
+
+err_irq:
+ for (; i >= 0; --i)
+ if (x3proto_gpio_irq_map[i])
+ destroy_irq(x3proto_gpio_irq_map[i]);
+
+ ret = gpiochip_remove(&x3proto_gpio_chip);
+ if (unlikely(ret))
+ pr_err("Failed deregistering GPIO\n");
+
+err_gpio:
+ synchronize_irq(ilsel);
+
+ ilsel_disable(ILSEL_KEY);
+
+ return ret;
+}