[ARM] 3140/1: NSLU2 machine support

Patch from Alessandro Zummo

This patch adds support for the LinkSys NSLU2 running with
both big and little-endian kernels. The LinkSys NSLU2 is
a cost engineered ARM, XScale 420 based system similar to
the the Intel IXDP425 evaluation board. It uses the
IXP4XX ARCH.

While this patch applies independently of other patches
the resultant kernel requires further patches to successfully
use onboard devices, including the onboard flash. Since these
patches are independent of this one they will be submitted
separately.

A defconfig is not included here because not all of
the required drivers are actually in the kernel.
We intend to provide one as soon as the patches
will be incorporated in mainstream.

This patch is the combined work of nslu2-linux.org

Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 92 insertions, 0 deletions

diff --git a/arch/arm/mach-ixp4xx/nslu2-power.c b/arch/arm/mach-ixp4xx/nslu2-power.c
new file mode 100644
index 0000000000000..18fbc8c0fb306
--- /dev/null
+++ b/arch/arm/mach-ixp4xx/nslu2-power.c
@@ -0,0 +1,92 @@
+/*
+ * arch/arm/mach-ixp4xx/nslu2-power.c
+ *
+ * NSLU2 Power/Reset driver
+ *
+ * Copyright (C) 2005 Tower Technologies
+ *
+ * based on nslu2-io.c
+ *  Copyright (C) 2004 Karen Spearel
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ * Maintainers: http://www.nslu2-linux.org/
+ *
+ * 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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/interrupt.h>
+
+#include <asm/mach-types.h>
+
+extern void ctrl_alt_del(void);
+
+static irqreturn_t nslu2_power_handler(int irq, void *dev_id, struct pt_regs *regs)
+{
+	/* Signal init to do the ctrlaltdel action, this will bypass init if
+	 * it hasn't started and do a kernel_restart.
+	 */
+	ctrl_alt_del();
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t nslu2_reset_handler(int irq, void *dev_id, struct pt_regs *regs)
+{
+	/* This is the paper-clip reset, it shuts the machine down directly.
+	 */
+	machine_power_off();
+
+	return IRQ_HANDLED;
+}
+
+static int __init nslu2_power_init(void)
+{
+	if (!(machine_is_nslu2()))
+		return 0;
+
+	*IXP4XX_GPIO_GPISR = 0x20400000;	/* read the 2 irqs to clr */
+
+	set_irq_type(NSLU2_RB_IRQ, IRQT_LOW);
+	set_irq_type(NSLU2_PB_IRQ, IRQT_HIGH);
+
+	gpio_line_isr_clear(NSLU2_RB_GPIO);
+	gpio_line_isr_clear(NSLU2_PB_GPIO);
+
+	if (request_irq(NSLU2_RB_IRQ, &nslu2_reset_handler,
+		SA_INTERRUPT, "NSLU2 reset button", NULL) < 0) {
+
+		printk(KERN_DEBUG "Reset Button IRQ %d not available\n",
+			NSLU2_RB_IRQ);
+
+		return -EIO;
+	}
+
+	if (request_irq(NSLU2_PB_IRQ, &nslu2_power_handler,
+		SA_INTERRUPT, "NSLU2 power button", NULL) < 0) {
+
+		printk(KERN_DEBUG "Power Button IRQ %d not available\n",
+			NSLU2_PB_IRQ);
+
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static void __exit nslu2_power_exit(void)
+{
+	free_irq(NSLU2_RB_IRQ, NULL);
+	free_irq(NSLU2_PB_IRQ, NULL);
+}
+
+module_init(nslu2_power_init);
+module_exit(nslu2_power_exit);
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("NSLU2 Power/Reset driver");
+MODULE_LICENSE("GPL");