suspend: constify platform_suspend_ops
[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 #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
24 static unsigned long db1x_pm_sleep_secs;
25 static unsigned long db1x_pm_wakemsk;
26 static unsigned long db1x_pm_last_wakesrc;
27
28 static 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         au_writel(0, SYS_WAKEMSK);
49         au_sync();
50         au_writel(0, SYS_WAKESRC);
51         au_sync();
52
53         au_writel(db1x_pm_wakemsk, SYS_WAKEMSK);
54         au_sync();
55
56         /* setup 1Hz-timer-based wakeup: wait for reg access */
57         while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20)
58                 asm volatile ("nop");
59
60         au_writel(au_readl(SYS_TOYREAD) + db1x_pm_sleep_secs, SYS_TOYMATCH2);
61         au_sync();
62
63         /* wait for value to really hit the register */
64         while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20)
65                 asm volatile ("nop");
66
67         /* ...and now the sandman can come! */
68         au_sleep();
69
70
71         /* restore CPLD regs */
72         for (i = BCSR_STATUS; i <= BCSR_SYSTEM; i++)
73                 bcsr_write(i, bcsrs[i]);
74
75         /* restore CPLD int registers */
76         if (hasint) {
77                 bcsr_write(BCSR_INTCLR, 0xffff);
78                 bcsr_write(BCSR_MASKCLR, 0xffff);
79                 bcsr_write(BCSR_INTSTAT, 0xffff);
80                 bcsr_write(BCSR_INTSET, bcsrs[BCSR_INTSET]);
81                 bcsr_write(BCSR_MASKSET, bcsrs[BCSR_MASKSET]);
82         }
83
84         /* light up hexleds */
85         bcsr_write(BCSR_HEXCLEAR, 0);
86
87         return 0;
88 }
89
90 static int db1x_pm_begin(suspend_state_t state)
91 {
92         if (!db1x_pm_wakemsk) {
93                 printk(KERN_ERR "db1x: no wakeup source activated!\n");
94                 return -EINVAL;
95         }
96
97         return 0;
98 }
99
100 static void db1x_pm_end(void)
101 {
102         /* read and store wakeup source, the clear the register. To
103          * be able to clear it, WAKEMSK must be cleared first.
104          */
105         db1x_pm_last_wakesrc = au_readl(SYS_WAKESRC);
106
107         au_writel(0, SYS_WAKEMSK);
108         au_writel(0, SYS_WAKESRC);
109         au_sync();
110
111 }
112
113 static const struct platform_suspend_ops db1x_pm_ops = {
114         .valid          = suspend_valid_only_mem,
115         .begin          = db1x_pm_begin,
116         .enter          = db1x_pm_enter,
117         .end            = db1x_pm_end,
118 };
119
120 #define ATTRCMP(x) (0 == strcmp(attr->attr.name, #x))
121
122 static ssize_t db1x_pmattr_show(struct kobject *kobj,
123                                 struct kobj_attribute *attr,
124                                 char *buf)
125 {
126         int idx;
127
128         if (ATTRCMP(timer_timeout))
129                 return sprintf(buf, "%lu\n", db1x_pm_sleep_secs);
130
131         else if (ATTRCMP(timer))
132                 return sprintf(buf, "%u\n",
133                                 !!(db1x_pm_wakemsk & SYS_WAKEMSK_M2));
134
135         else if (ATTRCMP(wakesrc))
136                 return sprintf(buf, "%lu\n", db1x_pm_last_wakesrc);
137
138         else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
139                  ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
140                  ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
141                 idx = (attr->attr.name)[4] - '0';
142                 return sprintf(buf, "%d\n",
143                         !!(db1x_pm_wakemsk & SYS_WAKEMSK_GPIO(idx)));
144
145         } else if (ATTRCMP(wakemsk)) {
146                 return sprintf(buf, "%08lx\n", db1x_pm_wakemsk);
147         }
148
149         return -ENOENT;
150 }
151
152 static ssize_t db1x_pmattr_store(struct kobject *kobj,
153                                  struct kobj_attribute *attr,
154                                  const char *instr,
155                                  size_t bytes)
156 {
157         unsigned long l;
158         int tmp;
159
160         if (ATTRCMP(timer_timeout)) {
161                 tmp = strict_strtoul(instr, 0, &l);
162                 if (tmp)
163                         return tmp;
164
165                 db1x_pm_sleep_secs = l;
166
167         } else if (ATTRCMP(timer)) {
168                 if (instr[0] != '0')
169                         db1x_pm_wakemsk |= SYS_WAKEMSK_M2;
170                 else
171                         db1x_pm_wakemsk &= ~SYS_WAKEMSK_M2;
172
173         } else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
174                    ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
175                    ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
176                 tmp = (attr->attr.name)[4] - '0';
177                 if (instr[0] != '0') {
178                         db1x_pm_wakemsk |= SYS_WAKEMSK_GPIO(tmp);
179                 } else {
180                         db1x_pm_wakemsk &= ~SYS_WAKEMSK_GPIO(tmp);
181                 }
182
183         } else if (ATTRCMP(wakemsk)) {
184                 tmp = strict_strtoul(instr, 0, &l);
185                 if (tmp)
186                         return tmp;
187
188                 db1x_pm_wakemsk = l & 0x0000003f;
189
190         } else
191                 bytes = -ENOENT;
192
193         return bytes;
194 }
195
196 #define ATTR(x)                                                 \
197         static struct kobj_attribute x##_attribute =            \
198                 __ATTR(x, 0664, db1x_pmattr_show,               \
199                                 db1x_pmattr_store);
200
201 ATTR(gpio0)             /* GPIO-based wakeup enable */
202 ATTR(gpio1)
203 ATTR(gpio2)
204 ATTR(gpio3)
205 ATTR(gpio4)
206 ATTR(gpio5)
207 ATTR(gpio6)
208 ATTR(gpio7)
209 ATTR(timer)             /* TOYMATCH2-based wakeup enable */
210 ATTR(timer_timeout)     /* timer-based wakeup timeout value, in seconds */
211 ATTR(wakesrc)           /* contents of SYS_WAKESRC after last wakeup */
212 ATTR(wakemsk)           /* direct access to SYS_WAKEMSK */
213
214 #define ATTR_LIST(x)    & x ## _attribute.attr
215 static struct attribute *db1x_pmattrs[] = {
216         ATTR_LIST(gpio0),
217         ATTR_LIST(gpio1),
218         ATTR_LIST(gpio2),
219         ATTR_LIST(gpio3),
220         ATTR_LIST(gpio4),
221         ATTR_LIST(gpio5),
222         ATTR_LIST(gpio6),
223         ATTR_LIST(gpio7),
224         ATTR_LIST(timer),
225         ATTR_LIST(timer_timeout),
226         ATTR_LIST(wakesrc),
227         ATTR_LIST(wakemsk),
228         NULL,           /* terminator */
229 };
230
231 static struct attribute_group db1x_pmattr_group = {
232         .name   = "db1x",
233         .attrs  = db1x_pmattrs,
234 };
235
236 /*
237  * Initialize suspend interface
238  */
239 static int __init pm_init(void)
240 {
241         /* init TOY to tick at 1Hz if not already done. No need to wait
242          * for confirmation since there's plenty of time from here to
243          * the next suspend cycle.
244          */
245         if (au_readl(SYS_TOYTRIM) != 32767) {
246                 au_writel(32767, SYS_TOYTRIM);
247                 au_sync();
248         }
249
250         db1x_pm_last_wakesrc = au_readl(SYS_WAKESRC);
251
252         au_writel(0, SYS_WAKESRC);
253         au_sync();
254         au_writel(0, SYS_WAKEMSK);
255         au_sync();
256
257         suspend_set_ops(&db1x_pm_ops);
258
259         return sysfs_create_group(power_kobj, &db1x_pmattr_group);
260 }
261
262 late_initcall(pm_init);