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>

diff --git a/arch/sh/boards/mach-x3proto/Makefile b/arch/sh/boards/mach-x3proto/Makefile
index 983e4551fecff8c39656b1993c696abbb764933d..708c21c919ff8c46dc71222afaf668d11b31738c 100644 (file)
--- 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 (file)
index 0000000..9fcd7ce
--- /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;
+}

diff --git a/arch/sh/include/mach-x3proto/mach/hardware.h b/arch/sh/include/mach-x3proto/mach/hardware.h
new file mode 100644 (file)
index 0000000..52bca57
--- /dev/null
+++ b/arch/sh/include/mach-x3proto/mach/hardware.h
@@ -0,0 +1,12 @@
+#ifndef __MACH_X3PROTO_HARDWARE_H
+#define __MACH_X3PROTO_HARDWARE_H
+
+struct gpio_chip;
+
+/* arch/sh/boards/mach-x3proto/gpio.c */
+int x3proto_gpio_setup(void);
+extern struct gpio_chip x3proto_gpio_chip;
+
+#define NR_BASEBOARD_GPIOS     16
+
+#endif /* __MACH_X3PROTO_HARDWARE_H */