1/*
2 * Alchemy Development Board example suspend userspace interface.
3 *
4 * (c) 2008 Manuel Lauss <mano@roarinelk.homelinux.net>
5 */
6
7#include <linux/init.h>
8#include <linux/kobject.h>
9#include <linux/suspend.h>
10#include <linux/sysfs.h>
11#include <asm/mach-au1x00/au1000.h>
12#include <asm/mach-au1x00/gpio.h>
13#include <asm/mach-db1x00/bcsr.h>
14
15/*
16 * Generic suspend userspace interface for Alchemy development boards.
17 * This code exports a few sysfs nodes under /sys/power/db1x/ which
18 * can be used by userspace to en/disable all au1x-provided wakeup
19 * sources and configure the timeout after which the the TOYMATCH2 irq
20 * is to trigger a wakeup.
21 */
22
23
24static unsigned long db1x_pm_sleep_secs;
25static unsigned long db1x_pm_wakemsk;
26static unsigned long db1x_pm_last_wakesrc;
27
28static int db1x_pm_enter(suspend_state_t state)
29{
30	unsigned short bcsrs[16];
31	int i, j, hasint;
32
33	/* save CPLD regs */
34	hasint = bcsr_read(BCSR_WHOAMI);
35	hasint = BCSR_WHOAMI_BOARD(hasint) >= BCSR_WHOAMI_DB1200;
36	j = (hasint) ? BCSR_MASKSET : BCSR_SYSTEM;
37
38	for (i = BCSR_STATUS; i <= j; i++)
39		bcsrs[i] = bcsr_read(i);
40
41	/* shut off hexleds */
42	bcsr_write(BCSR_HEXCLEAR, 3);
43
44	/* enable GPIO based wakeup */
45	alchemy_gpio1_input_enable();
46
47	/* clear and setup wake cause and source */
48	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
49	alchemy_wrsys(0, AU1000_SYS_WAKESRC);
50
51	alchemy_wrsys(db1x_pm_wakemsk, AU1000_SYS_WAKEMSK);
52
53	/* setup 1Hz-timer-based wakeup: wait for reg access */
54	while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
55		asm volatile ("nop");
56
57	alchemy_wrsys(alchemy_rdsys(AU1000_SYS_TOYREAD) + db1x_pm_sleep_secs,
58		      AU1000_SYS_TOYMATCH2);
59
60	/* wait for value to really hit the register */
61	while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
62		asm volatile ("nop");
63
64	/* ...and now the sandman can come! */
65	au_sleep();
66
67
68	/* restore CPLD regs */
69	for (i = BCSR_STATUS; i <= BCSR_SYSTEM; i++)
70		bcsr_write(i, bcsrs[i]);
71
72	/* restore CPLD int registers */
73	if (hasint) {
74		bcsr_write(BCSR_INTCLR, 0xffff);
75		bcsr_write(BCSR_MASKCLR, 0xffff);
76		bcsr_write(BCSR_INTSTAT, 0xffff);
77		bcsr_write(BCSR_INTSET, bcsrs[BCSR_INTSET]);
78		bcsr_write(BCSR_MASKSET, bcsrs[BCSR_MASKSET]);
79	}
80
81	/* light up hexleds */
82	bcsr_write(BCSR_HEXCLEAR, 0);
83
84	return 0;
85}
86
87static int db1x_pm_begin(suspend_state_t state)
88{
89	if (!db1x_pm_wakemsk) {
90		printk(KERN_ERR "db1x: no wakeup source activated!\n");
91		return -EINVAL;
92	}
93
94	return 0;
95}
96
97static void db1x_pm_end(void)
98{
99	/* read and store wakeup source, the clear the register. To
100	 * be able to clear it, WAKEMSK must be cleared first.
101	 */
102	db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);
103
104	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
105	alchemy_wrsys(0, AU1000_SYS_WAKESRC);
106}
107
108static const struct platform_suspend_ops db1x_pm_ops = {
109	.valid		= suspend_valid_only_mem,
110	.begin		= db1x_pm_begin,
111	.enter		= db1x_pm_enter,
112	.end		= db1x_pm_end,
113};
114
115#define ATTRCMP(x) (0 == strcmp(attr->attr.name, #x))
116
117static ssize_t db1x_pmattr_show(struct kobject *kobj,
118				struct kobj_attribute *attr,
119				char *buf)
120{
121	int idx;
122
123	if (ATTRCMP(timer_timeout))
124		return sprintf(buf, "%lu\n", db1x_pm_sleep_secs);
125
126	else if (ATTRCMP(timer))
127		return sprintf(buf, "%u\n",
128				!!(db1x_pm_wakemsk & SYS_WAKEMSK_M2));
129
130	else if (ATTRCMP(wakesrc))
131		return sprintf(buf, "%lu\n", db1x_pm_last_wakesrc);
132
133	else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
134		 ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
135		 ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
136		idx = (attr->attr.name)[4] - '0';
137		return sprintf(buf, "%d\n",
138			!!(db1x_pm_wakemsk & SYS_WAKEMSK_GPIO(idx)));
139
140	} else if (ATTRCMP(wakemsk)) {
141		return sprintf(buf, "%08lx\n", db1x_pm_wakemsk);
142	}
143
144	return -ENOENT;
145}
146
147static ssize_t db1x_pmattr_store(struct kobject *kobj,
148				 struct kobj_attribute *attr,
149				 const char *instr,
150				 size_t bytes)
151{
152	unsigned long l;
153	int tmp;
154
155	if (ATTRCMP(timer_timeout)) {
156		tmp = kstrtoul(instr, 0, &l);
157		if (tmp)
158			return tmp;
159
160		db1x_pm_sleep_secs = l;
161
162	} else if (ATTRCMP(timer)) {
163		if (instr[0] != '0')
164			db1x_pm_wakemsk |= SYS_WAKEMSK_M2;
165		else
166			db1x_pm_wakemsk &= ~SYS_WAKEMSK_M2;
167
168	} else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
169		   ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
170		   ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
171		tmp = (attr->attr.name)[4] - '0';
172		if (instr[0] != '0') {
173			db1x_pm_wakemsk |= SYS_WAKEMSK_GPIO(tmp);
174		} else {
175			db1x_pm_wakemsk &= ~SYS_WAKEMSK_GPIO(tmp);
176		}
177
178	} else if (ATTRCMP(wakemsk)) {
179		tmp = kstrtoul(instr, 0, &l);
180		if (tmp)
181			return tmp;
182
183		db1x_pm_wakemsk = l & 0x0000003f;
184
185	} else
186		bytes = -ENOENT;
187
188	return bytes;
189}
190
191#define ATTR(x)							\
192	static struct kobj_attribute x##_attribute =		\
193		__ATTR(x, 0664, db1x_pmattr_show,		\
194				db1x_pmattr_store);
195
196ATTR(gpio0)		/* GPIO-based wakeup enable */
197ATTR(gpio1)
198ATTR(gpio2)
199ATTR(gpio3)
200ATTR(gpio4)
201ATTR(gpio5)
202ATTR(gpio6)
203ATTR(gpio7)
204ATTR(timer)		/* TOYMATCH2-based wakeup enable */
205ATTR(timer_timeout)	/* timer-based wakeup timeout value, in seconds */
206ATTR(wakesrc)		/* contents of SYS_WAKESRC after last wakeup */
207ATTR(wakemsk)		/* direct access to SYS_WAKEMSK */
208
209#define ATTR_LIST(x)	& x ## _attribute.attr
210static struct attribute *db1x_pmattrs[] = {
211	ATTR_LIST(gpio0),
212	ATTR_LIST(gpio1),
213	ATTR_LIST(gpio2),
214	ATTR_LIST(gpio3),
215	ATTR_LIST(gpio4),
216	ATTR_LIST(gpio5),
217	ATTR_LIST(gpio6),
218	ATTR_LIST(gpio7),
219	ATTR_LIST(timer),
220	ATTR_LIST(timer_timeout),
221	ATTR_LIST(wakesrc),
222	ATTR_LIST(wakemsk),
223	NULL,		/* terminator */
224};
225
226static struct attribute_group db1x_pmattr_group = {
227	.name	= "db1x",
228	.attrs	= db1x_pmattrs,
229};
230
231/*
232 * Initialize suspend interface
233 */
234static int __init pm_init(void)
235{
236	/* init TOY to tick at 1Hz if not already done. No need to wait
237	 * for confirmation since there's plenty of time from here to
238	 * the next suspend cycle.
239	 */
240	if (alchemy_rdsys(AU1000_SYS_TOYTRIM) != 32767)
241		alchemy_wrsys(32767, AU1000_SYS_TOYTRIM);
242
243	db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);
244
245	alchemy_wrsys(0, AU1000_SYS_WAKESRC);
246	alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
247
248	suspend_set_ops(&db1x_pm_ops);
249
250	return sysfs_create_group(power_kobj, &db1x_pmattr_group);
251}
252
253late_initcall(pm_init);
254