summaryrefslogtreecommitdiffstats
path: root/kernel/arch/mips/alchemy/devboards/pm.c
blob: 93024dc6b314d904dc297ec5691975b5fd35ea6c (plain)
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
/*
 * Alchemy Development Board example suspend userspace interface.
 *
 * (c) 2008 Manuel Lauss <mano@roarinelk.homelinux.net>
 */

#include <linux/init.h>
#include <linux/kobject.h>
#include <linux/suspend.h>
#include <linux/sysfs.h>
#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/gpio-au1000.h>
#include <asm/mach-db1x00/bcsr.h>

/*
 * Generic suspend userspace interface for Alchemy development boards.
 * This code exports a few sysfs nodes under /sys/power/db1x/ which
 * can be used by userspace to en/disable all au1x-provided wakeup
 * sources and configure the timeout after which the the TOYMATCH2 irq
 * is to trigger a wakeup.
 */


static unsigned long db1x_pm_sleep_secs;
static unsigned long db1x_pm_wakemsk;
static unsigned long db1x_pm_last_wakesrc;

static int db1x_pm_enter(suspend_state_t state)
{
	unsigned short bcsrs[16];
	int i, j, hasint;

	/* save CPLD regs */
	hasint = bcsr_read(BCSR_WHOAMI);
	hasint = BCSR_WHOAMI_BOARD(hasint) >= BCSR_WHOAMI_DB1200;
	j = (hasint) ? BCSR_MASKSET : BCSR_SYSTEM;

	for (i = BCSR_STATUS; i <= j; i++)
		bcsrs[i] = bcsr_read(i);

	/* shut off hexleds */
	bcsr_write(BCSR_HEXCLEAR, 3);

	/* enable GPIO based wakeup */
	alchemy_gpio1_input_enable();

	/* clear and setup wake cause and source */
	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
	alchemy_wrsys(0, AU1000_SYS_WAKESRC);

	alchemy_wrsys(db1x_pm_wakemsk, AU1000_SYS_WAKEMSK);

	/* setup 1Hz-timer-based wakeup: wait for reg access */
	while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
		asm volatile ("nop");

	alchemy_wrsys(alchemy_rdsys(AU1000_SYS_TOYREAD) + db1x_pm_sleep_secs,
		      AU1000_SYS_TOYMATCH2);

	/* wait for value to really hit the register */
	while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
		asm volatile ("nop");

	/* ...and now the sandman can come! */
	au_sleep();


	/* restore CPLD regs */
	for (i = BCSR_STATUS; i <= BCSR_SYSTEM; i++)
		bcsr_write(i, bcsrs[i]);

	/* restore CPLD int registers */
	if (hasint) {
		bcsr_write(BCSR_INTCLR, 0xffff);
		bcsr_write(BCSR_MASKCLR, 0xffff);
		bcsr_write(BCSR_INTSTAT, 0xffff);
		bcsr_write(BCSR_INTSET, bcsrs[BCSR_INTSET]);
		bcsr_write(BCSR_MASKSET, bcsrs[BCSR_MASKSET]);
	}

	/* light up hexleds */
	bcsr_write(BCSR_HEXCLEAR, 0);

	return 0;
}

static int db1x_pm_begin(suspend_state_t state)
{
	if (!db1x_pm_wakemsk) {
		printk(KERN_ERR "db1x: no wakeup source activated!\n");
		return -EINVAL;
	}

	return 0;
}

static void db1x_pm_end(void)
{
	/* read and store wakeup source, the clear the register. To
	 * be able to clear it, WAKEMSK must be cleared first.
	 */
	db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);

	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
	alchemy_wrsys(0, AU1000_SYS_WAKESRC);
}

static const struct platform_suspend_ops db1x_pm_ops = {
	.valid		= suspend_valid_only_mem,
	.begin		= db1x_pm_begin,
	.enter		= db1x_pm_enter,
	.end		= db1x_pm_end,
};

#define ATTRCMP(x) (0 == strcmp(attr->attr.name, #x))

static ssize_t db1x_pmattr_show(struct kobject *kobj,
				struct kobj_attribute *attr,
				char *buf)
{
	int idx;

	if (ATTRCMP(timer_timeout))
		return sprintf(buf, "%lu\n", db1x_pm_sleep_secs);

	else if (ATTRCMP(timer))
		return sprintf(buf, "%u\n",
				!!(db1x_pm_wakemsk & SYS_WAKEMSK_M2));

	else if (ATTRCMP(wakesrc))
		return sprintf(buf, "%lu\n", db1x_pm_last_wakesrc);

	else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
		 ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
		 ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
		idx = (attr->attr.name)[4] - '0';
		return sprintf(buf, "%d\n",
			!!(db1x_pm_wakemsk & SYS_WAKEMSK_GPIO(idx)));

	} else if (ATTRCMP(wakemsk)) {
		return sprintf(buf, "%08lx\n", db1x_pm_wakemsk);
	}

	return -ENOENT;
}

static ssize_t db1x_pmattr_store(struct kobject *kobj,
				 struct kobj_attribute *attr,
				 const char *instr,
				 size_t bytes)
{
	unsigned long l;
	int tmp;

	if (ATTRCMP(timer_timeout)) {
		tmp = kstrtoul(instr, 0, &l);
		if (tmp)
			return tmp;

		db1x_pm_sleep_secs = l;

	} else if (ATTRCMP(timer)) {
		if (instr[0] != '0')
			db1x_pm_wakemsk |= SYS_WAKEMSK_M2;
		else
			db1x_pm_wakemsk &= ~SYS_WAKEMSK_M2;

	} else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
		   ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
		   ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
		tmp = (attr->attr.name)[4] - '0';
		if (instr[0] != '0') {
			db1x_pm_wakemsk |= SYS_WAKEMSK_GPIO(tmp);
		} else {
			db1x_pm_wakemsk &= ~SYS_WAKEMSK_GPIO(tmp);
		}

	} else if (ATTRCMP(wakemsk)) {
		tmp = kstrtoul(instr, 0, &l);
		if (tmp)
			return tmp;

		db1x_pm_wakemsk = l & 0x0000003f;

	} else
		bytes = -ENOENT;

	return bytes;
}

#define ATTR(x)							\
	static struct kobj_attribute x##_attribute =		\
		__ATTR(x, 0664, db1x_pmattr_show,		\
				db1x_pmattr_store);

ATTR(gpio0)		/* GPIO-based wakeup enable */
ATTR(gpio1)
ATTR(gpio2)
ATTR(gpio3)
ATTR(gpio4)
ATTR(gpio5)
ATTR(gpio6)
ATTR(gpio7)
ATTR(timer)		/* TOYMATCH2-based wakeup enable */
ATTR(timer_timeout)	/* timer-based wakeup timeout value, in seconds */
ATTR(wakesrc)		/* contents of SYS_WAKESRC after last wakeup */
ATTR(wakemsk)		/* direct access to SYS_WAKEMSK */

#define ATTR_LIST(x)	& x ## _attribute.attr
static struct attribute *db1x_pmattrs[] = {
	ATTR_LIST(gpio0),
	ATTR_LIST(gpio1),
	ATTR_LIST(gpio2),
	ATTR_LIST(gpio3),
	ATTR_LIST(gpio4),
	ATTR_LIST(gpio5),
	ATTR_LIST(gpio6),
	ATTR_LIST(gpio7),
	ATTR_LIST(timer),
	ATTR_LIST(timer_timeout),
	ATTR_LIST(wakesrc),
	ATTR_LIST(wakemsk),
	NULL,		/* terminator */
};

static struct attribute_group db1x_pmattr_group = {
	.name	= "db1x",
	.attrs	= db1x_pmattrs,
};

/*
 * Initialize suspend interface
 */
static int __init pm_init(void)
{
	/* init TOY to tick at 1Hz if not already done. No need to wait
	 * for confirmation since there's plenty of time from here to
	 * the next suspend cycle.
	 */
	if (alchemy_rdsys(AU1000_SYS_TOYTRIM) != 32767)
		alchemy_wrsys(32767, AU1000_SYS_TOYTRIM);

	db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);

	alchemy_wrsys(0, AU1000_SYS_WAKESRC);
	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);

	suspend_set_ops(&db1x_pm_ops);

	return sysfs_create_group(power_kobj, &db1x_pmattr_group);
}

late_initcall(pm_init);