1 files changed, 125 insertions, 0 deletions

diff --git a/arch/arm/mach-ixp4xx/dsmg600-power.c b/arch/arm/mach-ixp4xx/dsmg600-power.c
new file mode 100644
index 000000000000..34717872d076
--- /dev/null
+++ b/arch/arm/mach-ixp4xx/dsmg600-power.c
@@ -0,0 +1,125 @@
+/*
+ * arch/arm/mach-ixp4xx/dsmg600-power.c
+ *
+ * DSM-G600 Power/Reset driver
+ * Author: Michael Westerhof <mwester@dls.net>
+ *
+ * Based on nslu2-power.c
+ *  Copyright (C) 2005 Tower Technologies
+ *  Author: Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * which was based on nslu2-io.c
+ *  Copyright (C) 2004 Karen Spearel
+ *
+ * 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 <linux/irq.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+
+#include <asm/mach-types.h>
+
+extern void ctrl_alt_del(void);
+
+/* This is used to make sure the power-button pusher is serious.  The button
+ * must be held until the value of this counter reaches zero.
+ */
+static volatile int power_button_countdown;
+
+/* Must hold the button down for at least this many counts to be processed */
+#define PBUTTON_HOLDDOWN_COUNT 4 /* 2 secs */
+
+static void dsmg600_power_handler(unsigned long data);
+static DEFINE_TIMER(dsmg600_power_timer, dsmg600_power_handler, 0, 0);
+
+static void dsmg600_power_handler(unsigned long data)
+{
+        /* This routine is called twice per second to check the
+         * state of the power button.
+         */
+
+        if (*IXP4XX_GPIO_GPINR & DSMG600_PB_BM) {
+
+                /* IO Pin is 1 (button pushed) */
+                if (power_button_countdown == 0) {
+                        /* Signal init to do the ctrlaltdel action, this will bypass
+                         * init if it hasn't started and do a kernel_restart.
+                         */
+                        ctrl_alt_del();
+
+                        /* Change the state of the power LED to "blink" */
+                        gpio_line_set(DSMG600_LED_PWR_GPIO, IXP4XX_GPIO_LOW);
+                }
+                power_button_countdown--;
+
+        } else {
+                power_button_countdown = PBUTTON_HOLDDOWN_COUNT;
+        }
+
+        mod_timer(&dsmg600_power_timer, jiffies + msecs_to_jiffies(500));
+}
+
+static irqreturn_t dsmg600_reset_handler(int irq, void *dev_id)
+{
+        /* This is the paper-clip reset, it shuts the machine down directly. */
+        machine_power_off();
+
+        return IRQ_HANDLED;
+}
+
+static int __init dsmg600_power_init(void)
+{
+        if (!(machine_is_dsmg600()))
+                return 0;
+
+        if (request_irq(DSMG600_RB_IRQ, &dsmg600_reset_handler,
+                IRQF_DISABLED | IRQF_TRIGGER_LOW, "DSM-G600 reset button",
+                NULL) < 0) {
+
+                printk(KERN_DEBUG "Reset Button IRQ %d not available\n",
+                        DSMG600_RB_IRQ);
+
+                return -EIO;
+        }
+
+        /* The power button on the D-Link DSM-G600 is on GPIO 15, but
+         * it cannot handle interrupts on that GPIO line.  So we'll
+         * have to poll it with a kernel timer.
+         */
+
+        /* Make sure that the power button GPIO is set up as an input */
+        gpio_line_config(DSMG600_PB_GPIO, IXP4XX_GPIO_IN);
+
+        /* Set the initial value for the power button IRQ handler */
+        power_button_countdown = PBUTTON_HOLDDOWN_COUNT;
+
+        mod_timer(&dsmg600_power_timer, jiffies + msecs_to_jiffies(500));
+
+        return 0;
+}
+
+static void __exit dsmg600_power_exit(void)
+{
+        if (!(machine_is_dsmg600()))
+                return;
+
+        del_timer_sync(&dsmg600_power_timer);
+
+        free_irq(DSMG600_RB_IRQ, NULL);
+}
+
+module_init(dsmg600_power_init);
+module_exit(dsmg600_power_exit);
+
+MODULE_AUTHOR("Michael Westerhof <mwester@dls.net>");
+MODULE_DESCRIPTION("DSM-G600 Power/Reset driver");
+MODULE_LICENSE("GPL");