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-au1000.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         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
  87 static 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
  97 static 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
 108 static 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
 117 static 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
 147 static 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
 196 ATTR(gpio0)             /* GPIO-based wakeup enable */
 197 ATTR(gpio1)
 198 ATTR(gpio2)
 199 ATTR(gpio3)
 200 ATTR(gpio4)
 201 ATTR(gpio5)
 202 ATTR(gpio6)
 203 ATTR(gpio7)
 204 ATTR(timer)             /* TOYMATCH2-based wakeup enable */
 205 ATTR(timer_timeout)     /* timer-based wakeup timeout value, in seconds */
 206 ATTR(wakesrc)           /* contents of SYS_WAKESRC after last wakeup */
 207 ATTR(wakemsk)           /* direct access to SYS_WAKEMSK */
 208
 209 #define ATTR_LIST(x)    & x ## _attribute.attr
 210 static 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
 226 static struct attribute_group db1x_pmattr_group = {
 227         .name   = "db1x",
 228         .attrs  = db1x_pmattrs,
 229 };
 230
 231 /*
 232  * Initialize suspend interface
 233  */
 234 static 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
 253 late_initcall(pm_init);