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);