diff options
author | Dmitry Torokhov <dtor@insightbb.com> | 2007-05-08 01:31:11 -0400 |
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committer | Dmitry Torokhov <dtor@insightbb.com> | 2007-05-08 01:31:11 -0400 |
commit | 334d0dd8b660557608142f0f77abc6812b48f08b (patch) | |
tree | 9393a9aa099d7d42deda5f9f5054796c0c769be7 /arch/arm/mach-ixp4xx/dsmg600-power.c | |
parent | 3f07d8796262f6aee135c8dd9a91210da9f888e4 (diff) | |
parent | 5b94f675f57e4ff16c8fda09088d7480a84dcd91 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Diffstat (limited to 'arch/arm/mach-ixp4xx/dsmg600-power.c')
-rw-r--r-- | arch/arm/mach-ixp4xx/dsmg600-power.c | 125 |
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 00000000000..34717872d07 --- /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"); |