[PARISC] Convert soft power switch driver to kthread
And remove it's reference in time.c.
Allow lcd_print() to take a const char *.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/drivers/parisc/power.c b/drivers/parisc/power.c
index 9228e21..6dedbde 100644
--- a/drivers/parisc/power.c
+++ b/drivers/parisc/power.c
@@ -2,7 +2,7 @@
* linux/drivers/parisc/power.c
* HP PARISC soft power switch support driver
*
- * Copyright (c) 2001-2005 Helge Deller <deller@gmx.de>
+ * Copyright (c) 2001-2007 Helge Deller <deller@gmx.de>
* All rights reserved.
*
*
@@ -29,7 +29,6 @@
* 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.
@@ -38,34 +37,28 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
-#include <linux/string.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/workqueue.h>
+#include <linux/kthread.h>
#include <asm/pdc.h>
#include <asm/io.h>
#include <asm/led.h>
-#include <asm/uaccess.h>
+#define DRIVER_NAME "powersw"
+#define KTHREAD_NAME "kpowerswd"
-#ifdef DEBUG
-# define DPRINTK(x...) printk(x)
-#else
-# define DPRINTK(x...)
-#endif
+/* 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
-/* filename in /proc which can be used to enable/disable the power switch */
-#define SYSCTL_FILENAME "sys/kernel/power"
-
-
+/* assembly code to access special registers */
+/* taken from PCXL ERS page 82 */
#define DIAG_CODE(code) (0x14000000 + ((code)<<5))
-/* this will go to processor.h or any other place... */
-/* taken from PCXL ERS page 82 */
#define MFCPU_X(rDiagReg, t_ch, t_th, code) \
(DIAG_CODE(code) + ((rDiagReg)<<21) + ((t_ch)<<16) + ((t_th)<<0) )
@@ -76,111 +69,95 @@
#define __getDIAG(dr) ( { \
register unsigned long __res asm("r28");\
__asm__ __volatile__ ( \
- ".word %1\n nop\n" : "=&r" (__res) : "i" (MFCPU_T(dr,28)) \
+ ".word %1" : "=&r" (__res) : "i" (MFCPU_T(dr,28) ) \
); \
__res; \
} )
-
-static void deferred_poweroff(struct work_struct *unused)
-{
- if (kill_cad_pid(SIGINT, 1)) {
- /* just in case killing init process failed */
- machine_power_off();
- }
-}
-
-/*
- * This function gets called from interrupt context.
- * As it's called within an interrupt, it wouldn't sync if we don't
- * use schedule_work().
- */
-
-static DECLARE_WORK(poweroff_work, deferred_poweroff);
-
-static void poweroff(void)
-{
- static int powering_off __read_mostly;
-
- if (powering_off)
- return;
-
- powering_off++;
- schedule_work(&poweroff_work);
-}
-
-
-/* local time-counter for shutdown */
+/* 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)
- DPRINTK(KERN_INFO "Shutdown requested...\n");
+ printk(KERN_ALERT KTHREAD_NAME ": Shutdown requested...\n");
shutdown_timer++;
/* wait until the button was pressed for 1 second */
- if (shutdown_timer == HZ) {
-#if defined (DEBUG) || defined(CONFIG_CHASSIS_LCD_LED)
- static char msg[] = "Shutting down...";
-#endif
- DPRINTK(KERN_INFO "%s\n", msg);
+ 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);
- poweroff();
+
+ /* send kill signal */
+ if (kill_cad_pid(SIGINT, 1)) {
+ /* just in case killing init process failed */
+ if (pm_power_off)
+ pm_power_off();
+ }
}
}
-/* main power switch tasklet struct (scheduled from time.c) */
-DECLARE_TASKLET_DISABLED(power_tasklet, NULL, 0);
+/* 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;
-/*
- * 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.
- *
- */
-static void gecko_tasklet_func(unsigned long unused)
+/* main kernel thread worker. It polls the button state */
+static int kpowerswd(void *param)
{
- if (unlikely(!pwrsw_enabled))
- return;
+ __set_current_state(TASK_RUNNING);
- if (__getDIAG(25) & 0x80000000) {
- /* power switch button not pressed or released again */
- /* Warning: Some machines do never reset this DIAG flag! */
- shutdown_timer = 0;
- } else {
- process_shutdown();
- }
-}
+ do {
+ int button_not_pressed;
+ unsigned long soft_power_reg = (unsigned long) param;
+
+ schedule_timeout_interruptible(pwrsw_enabled ? HZ : HZ/POWERSWITCH_POLL_PER_SEC);
+ __set_current_state(TASK_RUNNING);
+
+ 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());
-/*
- * 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.
- */
-
-static void polling_tasklet_func(unsigned long soft_power_reg)
-{
- unsigned long current_status;
-
- if (unlikely(!pwrsw_enabled))
- return;
-
- current_status = gsc_readl(soft_power_reg);
- if (current_status & 0x1) {
- /* power switch button not pressed */
- shutdown_timer = 0;
- } else {
- process_shutdown();
- }
+ return 0;
}
@@ -220,7 +197,7 @@
static int __init power_init(void)
{
unsigned long ret;
- unsigned long soft_power_reg = 0;
+ unsigned long soft_power_reg;
#if 0
request_irq( IRQ_FROM_REGION(CPU_IRQ_REGION)+2, &powerfail_interrupt,
@@ -235,44 +212,44 @@
soft_power_reg = -1UL;
switch (soft_power_reg) {
- case 0: printk(KERN_INFO "Gecko-style soft power switch enabled.\n");
- power_tasklet.func = gecko_tasklet_func;
+ case 0: printk(KERN_INFO DRIVER_NAME ": Gecko-style soft power switch enabled.\n");
break;
- case -1UL: printk(KERN_INFO "Soft power switch support not available.\n");
+ case -1UL: printk(KERN_INFO DRIVER_NAME ": Soft power switch support not available.\n");
return -ENODEV;
- default: printk(KERN_INFO "Soft power switch enabled, polling @ 0x%08lx.\n",
+ default: printk(KERN_INFO DRIVER_NAME ": Soft power switch at 0x%08lx enabled.\n",
soft_power_reg);
- power_tasklet.data = soft_power_reg;
- power_tasklet.func = polling_tasklet_func;
+ }
+
+ 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);
- tasklet_enable(&power_tasklet);
-
return 0;
}
static void __exit power_exit(void)
{
- if (!power_tasklet.func)
- return;
+ kthread_stop(power_task);
- tasklet_disable(&power_tasklet);
atomic_notifier_chain_unregister(&panic_notifier_list,
&parisc_panic_block);
- power_tasklet.func = NULL;
+
pdc_soft_power_button(0);
}
-module_init(power_init);
+arch_initcall(power_init);
module_exit(power_exit);
-MODULE_AUTHOR("Helge Deller");
+MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
MODULE_DESCRIPTION("Soft power switch driver");
MODULE_LICENSE("Dual BSD/GPL");