1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/*
* 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");
|
