1 files changed, 278 insertions, 0 deletions

diff --git a/drivers/parisc/power.c b/drivers/parisc/power.c
new file mode 100644
index 000000000000..ff75e9296df9
--- /dev/null
+++ b/drivers/parisc/power.c
@@ -0,0 +1,278 @@
+/*
+ * linux/arch/parisc/kernel/power.c
+ * HP PARISC soft power switch support driver
+ *
+ * Copyright (c) 2001-2002 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/config.h>
+#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 <asm/pdc.h>
+#include <asm/io.h>
+#include <asm/led.h>
+#include <asm/uaccess.h>
+
+
+#ifdef DEBUG
+# define DPRINTK(x...) printk(x)
+#else
+# define DPRINTK(x...)
+#endif
+
+
+/* filename in /proc which can be used to enable/disable the power switch */
+#define SYSCTL_FILENAME         "sys/kernel/power"
+
+
+#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) )
+        
+#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\n nop\n" : "=&r" (__res) : "i" (MFCPU_T(dr,28)) \
+        );                                      \
+        __res;                                  \
+} )
+
+
+static void deferred_poweroff(void *dummy)
+{
+        extern int cad_pid;     /* from kernel/sys.c */
+        if (kill_proc(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, NULL);
+
+static void poweroff(void)
+{
+        static int powering_off;
+
+        if (powering_off)
+                return;
+
+        powering_off++;
+        schedule_work(&poweroff_work);
+}
+
+
+/* local time-counter for shutdown */
+static int shutdown_timer;
+
+/* check, give feedback and start shutdown after one second */
+static void process_shutdown(void)
+{
+        if (shutdown_timer == 0)
+                DPRINTK(KERN_INFO "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);
+                lcd_print(msg);
+                poweroff();
+        }
+}
+
+
+/* main power switch tasklet struct (scheduled from time.c) */
+DECLARE_TASKLET_DISABLED(power_tasklet, NULL, 0);
+
+/* soft power switch enabled/disabled */
+int pwrsw_enabled = 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)
+{
+        if (!pwrsw_enabled)
+                return;
+
+        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();
+        }
+}
+
+
+
+/*
+ * 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 (!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();
+        }
+}
+
+
+/*
+ * powerfail interruption handler (irq IRQ_FROM_REGION(CPU_IRQ_REGION)+2) 
+ */
+#if 0
+static void powerfail_interrupt(int code, void *x, struct pt_regs *regs)
+{
+        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 = 0;
+
+#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 "Gecko-style soft power switch enabled.\n");
+                        power_tasklet.func = gecko_tasklet_func;
+                        break;
+                        
+        case -1UL:      printk(KERN_INFO "Soft power switch support not available.\n");
+                        return -ENODEV;
+        
+        default:        printk(KERN_INFO "Soft power switch enabled, polling @ 0x%08lx.\n",
+                                soft_power_reg);
+                        power_tasklet.data = soft_power_reg;
+                        power_tasklet.func = polling_tasklet_func;
+        }
+
+        /* Register a call for panic conditions. */
+        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;
+
+        tasklet_disable(&power_tasklet);
+        notifier_chain_unregister(&panic_notifier_list, &parisc_panic_block);
+        power_tasklet.func = NULL;
+        pdc_soft_power_button(0);
+}
+
+module_init(power_init);
+module_exit(power_exit);
+
+
+MODULE_AUTHOR("Helge Deller");
+MODULE_DESCRIPTION("Soft power switch driver");
+MODULE_LICENSE("Dual BSD/GPL");