LXR linux/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
  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        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
  90static 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
 100static 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
 113static 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
 122static 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
 152static 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
 201ATTR(gpio0)             /* GPIO-based wakeup enable */
 202ATTR(gpio1)
 203ATTR(gpio2)
 204ATTR(gpio3)
 205ATTR(gpio4)
 206ATTR(gpio5)
 207ATTR(gpio6)
 208ATTR(gpio7)
 209ATTR(timer)             /* TOYMATCH2-based wakeup enable */
 210ATTR(timer_timeout)     /* timer-based wakeup timeout value, in seconds */
 211ATTR(wakesrc)           /* contents of SYS_WAKESRC after last wakeup */
 212ATTR(wakemsk)           /* direct access to SYS_WAKEMSK */
 213
 214#define ATTR_LIST(x)    & x ## _attribute.attr
 215static 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
 231static struct attribute_group db1x_pmattr_group = {
 232        .name   = "db1x",
 233        .attrs  = db1x_pmattrs,
 234};
 235
 236/*
 237 * Initialize suspend interface
 238 */
 239static 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
 262late_initcall(pm_init);
 263