mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
254 lines
7.2 KiB
C
254 lines
7.2 KiB
C
/*
|
|
* linux/drivers/parisc/power.c
|
|
* HP PARISC soft power switch support driver
|
|
*
|
|
* Copyright (c) 2001-2007 Helge Deller <deller@gmx.de>
|
|
* All rights reserved.
|
|
*
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions, and the following disclaimer,
|
|
* without modification.
|
|
* 2. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* Alternatively, this software may be distributed under the terms of the
|
|
* GNU General Public License ("GPL").
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
|
|
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
*
|
|
*
|
|
* HINT:
|
|
* Support of the soft power switch button may be enabled or disabled at
|
|
* runtime through the "/proc/sys/kernel/power" procfs entry.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/sched/signal.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/pm.h>
|
|
|
|
#include <asm/pdc.h>
|
|
#include <asm/io.h>
|
|
#include <asm/led.h>
|
|
|
|
#define DRIVER_NAME "powersw"
|
|
#define KTHREAD_NAME "kpowerswd"
|
|
|
|
/* how often should the power button be polled ? */
|
|
#define POWERSWITCH_POLL_PER_SEC 2
|
|
|
|
/* how long does the power button needs to be down until we react ? */
|
|
#define POWERSWITCH_DOWN_SEC 2
|
|
|
|
/* assembly code to access special registers */
|
|
/* taken from PCXL ERS page 82 */
|
|
#define DIAG_CODE(code) (0x14000000 + ((code)<<5))
|
|
|
|
#define MFCPU_X(rDiagReg, t_ch, t_th, code) \
|
|
(DIAG_CODE(code) + ((rDiagReg)<<21) + ((t_ch)<<16) + ((t_th)<<0) )
|
|
|
|
#define MTCPU(dr, gr) MFCPU_X(dr, gr, 0, 0x12) /* move value of gr to dr[dr] */
|
|
#define MFCPU_C(dr, gr) MFCPU_X(dr, gr, 0, 0x30) /* for dr0 and dr8 only ! */
|
|
#define MFCPU_T(dr, gr) MFCPU_X(dr, 0, gr, 0xa0) /* all dr except dr0 and dr8 */
|
|
|
|
#define __getDIAG(dr) ( { \
|
|
register unsigned long __res asm("r28");\
|
|
__asm__ __volatile__ ( \
|
|
".word %1" : "=&r" (__res) : "i" (MFCPU_T(dr,28) ) \
|
|
); \
|
|
__res; \
|
|
} )
|
|
|
|
/* local shutdown counter */
|
|
static int shutdown_timer __read_mostly;
|
|
|
|
/* check, give feedback and start shutdown after one second */
|
|
static void process_shutdown(void)
|
|
{
|
|
if (shutdown_timer == 0)
|
|
printk(KERN_ALERT KTHREAD_NAME ": Shutdown requested...\n");
|
|
|
|
shutdown_timer++;
|
|
|
|
/* wait until the button was pressed for 1 second */
|
|
if (shutdown_timer == (POWERSWITCH_DOWN_SEC*POWERSWITCH_POLL_PER_SEC)) {
|
|
static const char msg[] = "Shutting down...";
|
|
printk(KERN_INFO KTHREAD_NAME ": %s\n", msg);
|
|
lcd_print(msg);
|
|
|
|
/* send kill signal */
|
|
if (kill_cad_pid(SIGINT, 1)) {
|
|
/* just in case killing init process failed */
|
|
machine_power_off();
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* main power switch task struct */
|
|
static struct task_struct *power_task;
|
|
|
|
/* filename in /proc which can be used to enable/disable the power switch */
|
|
#define SYSCTL_FILENAME "sys/kernel/power"
|
|
|
|
/* soft power switch enabled/disabled */
|
|
int pwrsw_enabled __read_mostly = 1;
|
|
|
|
/* main kernel thread worker. It polls the button state */
|
|
static int kpowerswd(void *param)
|
|
{
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
do {
|
|
int button_not_pressed;
|
|
unsigned long soft_power_reg = (unsigned long) param;
|
|
|
|
schedule_timeout_interruptible(pwrsw_enabled ? HZ : HZ/POWERSWITCH_POLL_PER_SEC);
|
|
|
|
if (unlikely(!pwrsw_enabled))
|
|
continue;
|
|
|
|
if (soft_power_reg) {
|
|
/*
|
|
* Non-Gecko-style machines:
|
|
* Check the power switch status which is read from the
|
|
* real I/O location at soft_power_reg.
|
|
* Bit 31 ("the lowest bit) is the status of the power switch.
|
|
* This bit is "1" if the button is NOT pressed.
|
|
*/
|
|
button_not_pressed = (gsc_readl(soft_power_reg) & 0x1);
|
|
} else {
|
|
/*
|
|
* On gecko style machines (e.g. 712/xx and 715/xx)
|
|
* the power switch status is stored in Bit 0 ("the highest bit")
|
|
* of CPU diagnose register 25.
|
|
* Warning: Some machines never reset the DIAG flag, even if
|
|
* the button has been released again.
|
|
*/
|
|
button_not_pressed = (__getDIAG(25) & 0x80000000);
|
|
}
|
|
|
|
if (likely(button_not_pressed)) {
|
|
if (unlikely(shutdown_timer && /* avoid writing if not necessary */
|
|
shutdown_timer < (POWERSWITCH_DOWN_SEC*POWERSWITCH_POLL_PER_SEC))) {
|
|
shutdown_timer = 0;
|
|
printk(KERN_INFO KTHREAD_NAME ": Shutdown request aborted.\n");
|
|
}
|
|
} else
|
|
process_shutdown();
|
|
|
|
|
|
} while (!kthread_should_stop());
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* powerfail interruption handler (irq IRQ_FROM_REGION(CPU_IRQ_REGION)+2)
|
|
*/
|
|
#if 0
|
|
static void powerfail_interrupt(int code, void *x)
|
|
{
|
|
printk(KERN_CRIT "POWERFAIL INTERRUPTION !\n");
|
|
poweroff();
|
|
}
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* parisc_panic_event() is called by the panic handler.
|
|
* As soon as a panic occurs, our tasklets above will not be
|
|
* executed any longer. This function then re-enables the
|
|
* soft-power switch and allows the user to switch off the system
|
|
*/
|
|
static int parisc_panic_event(struct notifier_block *this,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
/* re-enable the soft-power switch */
|
|
pdc_soft_power_button(0);
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block parisc_panic_block = {
|
|
.notifier_call = parisc_panic_event,
|
|
.priority = INT_MAX,
|
|
};
|
|
|
|
|
|
static int __init power_init(void)
|
|
{
|
|
unsigned long ret;
|
|
unsigned long soft_power_reg;
|
|
|
|
#if 0
|
|
request_irq( IRQ_FROM_REGION(CPU_IRQ_REGION)+2, &powerfail_interrupt,
|
|
0, "powerfail", NULL);
|
|
#endif
|
|
|
|
/* enable the soft power switch if possible */
|
|
ret = pdc_soft_power_info(&soft_power_reg);
|
|
if (ret == PDC_OK)
|
|
ret = pdc_soft_power_button(1);
|
|
if (ret != PDC_OK)
|
|
soft_power_reg = -1UL;
|
|
|
|
switch (soft_power_reg) {
|
|
case 0: printk(KERN_INFO DRIVER_NAME ": Gecko-style soft power switch enabled.\n");
|
|
break;
|
|
|
|
case -1UL: printk(KERN_INFO DRIVER_NAME ": Soft power switch support not available.\n");
|
|
return -ENODEV;
|
|
|
|
default: printk(KERN_INFO DRIVER_NAME ": Soft power switch at 0x%08lx enabled.\n",
|
|
soft_power_reg);
|
|
}
|
|
|
|
power_task = kthread_run(kpowerswd, (void*)soft_power_reg, KTHREAD_NAME);
|
|
if (IS_ERR(power_task)) {
|
|
printk(KERN_ERR DRIVER_NAME ": thread creation failed. Driver not loaded.\n");
|
|
pdc_soft_power_button(0);
|
|
return -EIO;
|
|
}
|
|
|
|
/* Register a call for panic conditions. */
|
|
atomic_notifier_chain_register(&panic_notifier_list,
|
|
&parisc_panic_block);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit power_exit(void)
|
|
{
|
|
kthread_stop(power_task);
|
|
|
|
atomic_notifier_chain_unregister(&panic_notifier_list,
|
|
&parisc_panic_block);
|
|
|
|
pdc_soft_power_button(0);
|
|
}
|
|
|
|
arch_initcall(power_init);
|
|
module_exit(power_exit);
|
|
|
|
|
|
MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
|
|
MODULE_DESCRIPTION("Soft power switch driver");
|
|
MODULE_LICENSE("Dual BSD/GPL");
|