d5eb9c325ed0c91009641ff462f60aa9afd7711c
[linux-2.6.git] / arch / mips / alchemy / devboards / pm.c
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
13 /*
14  * Generic suspend userspace interface for Alchemy development boards.
15  * This code exports a few sysfs nodes under /sys/power/db1x/ which
16  * can be used by userspace to en/disable all au1x-provided wakeup
17  * sources and configure the timeout after which the the TOYMATCH2 irq
18  * is to trigger a wakeup.
19  */
20
21
22 static unsigned long db1x_pm_sleep_secs;
23 static unsigned long db1x_pm_wakemsk;
24 static unsigned long db1x_pm_last_wakesrc;
25
26 static int db1x_pm_enter(suspend_state_t state)
27 {
28         /* enable GPIO based wakeup */
29         au_writel(1, SYS_PININPUTEN);
30
31         /* clear and setup wake cause and source */
32         au_writel(0, SYS_WAKEMSK);
33         au_sync();
34         au_writel(0, SYS_WAKESRC);
35         au_sync();
36
37         au_writel(db1x_pm_wakemsk, SYS_WAKEMSK);
38         au_sync();
39
40         /* setup 1Hz-timer-based wakeup: wait for reg access */
41         while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20)
42                 asm volatile ("nop");
43
44         au_writel(au_readl(SYS_TOYREAD) + db1x_pm_sleep_secs, SYS_TOYMATCH2);
45         au_sync();
46
47         /* wait for value to really hit the register */
48         while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20)
49                 asm volatile ("nop");
50
51         /* ...and now the sandman can come! */
52         au_sleep();
53
54         return 0;
55 }
56
57 static int db1x_pm_begin(suspend_state_t state)
58 {
59         if (!db1x_pm_wakemsk) {
60                 printk(KERN_ERR "db1x: no wakeup source activated!\n");
61                 return -EINVAL;
62         }
63
64         return 0;
65 }
66
67 static void db1x_pm_end(void)
68 {
69         /* read and store wakeup source, the clear the register. To
70          * be able to clear it, WAKEMSK must be cleared first.
71          */
72         db1x_pm_last_wakesrc = au_readl(SYS_WAKESRC);
73
74         au_writel(0, SYS_WAKEMSK);
75         au_writel(0, SYS_WAKESRC);
76         au_sync();
77
78 }
79
80 static struct platform_suspend_ops db1x_pm_ops = {
81         .valid          = suspend_valid_only_mem,
82         .begin          = db1x_pm_begin,
83         .enter          = db1x_pm_enter,
84         .end            = db1x_pm_end,
85 };
86
87 #define ATTRCMP(x) (0 == strcmp(attr->attr.name, #x))
88
89 static ssize_t db1x_pmattr_show(struct kobject *kobj,
90                                 struct kobj_attribute *attr,
91                                 char *buf)
92 {
93         int idx;
94
95         if (ATTRCMP(timer_timeout))
96                 return sprintf(buf, "%lu\n", db1x_pm_sleep_secs);
97
98         else if (ATTRCMP(timer))
99                 return sprintf(buf, "%u\n",
100                                 !!(db1x_pm_wakemsk & SYS_WAKEMSK_M2));
101
102         else if (ATTRCMP(wakesrc))
103                 return sprintf(buf, "%lu\n", db1x_pm_last_wakesrc);
104
105         else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
106                  ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
107                  ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
108                 idx = (attr->attr.name)[4] - '0';
109                 return sprintf(buf, "%d\n",
110                         !!(db1x_pm_wakemsk & SYS_WAKEMSK_GPIO(idx)));
111
112         } else if (ATTRCMP(wakemsk)) {
113                 return sprintf(buf, "%08lx\n", db1x_pm_wakemsk);
114         }
115
116         return -ENOENT;
117 }
118
119 static ssize_t db1x_pmattr_store(struct kobject *kobj,
120                                  struct kobj_attribute *attr,
121                                  const char *instr,
122                                  size_t bytes)
123 {
124         unsigned long l;
125         int tmp;
126
127         if (ATTRCMP(timer_timeout)) {
128                 tmp = strict_strtoul(instr, 0, &l);
129                 if (tmp)
130                         return tmp;
131
132                 db1x_pm_sleep_secs = l;
133
134         } else if (ATTRCMP(timer)) {
135                 if (instr[0] != '0')
136                         db1x_pm_wakemsk |= SYS_WAKEMSK_M2;
137                 else
138                         db1x_pm_wakemsk &= ~SYS_WAKEMSK_M2;
139
140         } else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
141                    ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
142                    ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
143                 tmp = (attr->attr.name)[4] - '0';
144                 if (instr[0] != '0') {
145                         db1x_pm_wakemsk |= SYS_WAKEMSK_GPIO(tmp);
146                 } else {
147                         db1x_pm_wakemsk &= ~SYS_WAKEMSK_GPIO(tmp);
148                 }
149
150         } else if (ATTRCMP(wakemsk)) {
151                 tmp = strict_strtoul(instr, 0, &l);
152                 if (tmp)
153                         return tmp;
154
155                 db1x_pm_wakemsk = l & 0x0000003f;
156
157         } else
158                 bytes = -ENOENT;
159
160         return bytes;
161 }
162
163 #define ATTR(x)                                                 \
164         static struct kobj_attribute x##_attribute =            \
165                 __ATTR(x, 0664, db1x_pmattr_show,               \
166                                 db1x_pmattr_store);
167
168 ATTR(gpio0)             /* GPIO-based wakeup enable */
169 ATTR(gpio1)
170 ATTR(gpio2)
171 ATTR(gpio3)
172 ATTR(gpio4)
173 ATTR(gpio5)
174 ATTR(gpio6)
175 ATTR(gpio7)
176 ATTR(timer)             /* TOYMATCH2-based wakeup enable */
177 ATTR(timer_timeout)     /* timer-based wakeup timeout value, in seconds */
178 ATTR(wakesrc)           /* contents of SYS_WAKESRC after last wakeup */
179 ATTR(wakemsk)           /* direct access to SYS_WAKEMSK */
180
181 #define ATTR_LIST(x)    & x ## _attribute.attr
182 static struct attribute *db1x_pmattrs[] = {
183         ATTR_LIST(gpio0),
184         ATTR_LIST(gpio1),
185         ATTR_LIST(gpio2),
186         ATTR_LIST(gpio3),
187         ATTR_LIST(gpio4),
188         ATTR_LIST(gpio5),
189         ATTR_LIST(gpio6),
190         ATTR_LIST(gpio7),
191         ATTR_LIST(timer),
192         ATTR_LIST(timer_timeout),
193         ATTR_LIST(wakesrc),
194         ATTR_LIST(wakemsk),
195         NULL,           /* terminator */
196 };
197
198 static struct attribute_group db1x_pmattr_group = {
199         .name   = "db1x",
200         .attrs  = db1x_pmattrs,
201 };
202
203 /*
204  * Initialize suspend interface
205  */
206 static int __init pm_init(void)
207 {
208         /* init TOY to tick at 1Hz if not already done. No need to wait
209          * for confirmation since there's plenty of time from here to
210          * the next suspend cycle.
211          */
212         if (au_readl(SYS_TOYTRIM) != 32767) {
213                 au_writel(32767, SYS_TOYTRIM);
214                 au_sync();
215         }
216
217         db1x_pm_last_wakesrc = au_readl(SYS_WAKESRC);
218
219         au_writel(0, SYS_WAKESRC);
220         au_sync();
221         au_writel(0, SYS_WAKEMSK);
222         au_sync();
223
224         suspend_set_ops(&db1x_pm_ops);
225
226         return sysfs_create_group(power_kobj, &db1x_pmattr_group);
227 }
228
229 late_initcall(pm_init);