linux/arch/mips/alchemy/devboards/pm.c

255 lines
6.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Alchemy Development Board example suspend userspace interface.
*
* (c) 2008 Manuel Lauss <mano@roarinelk.homelinux.net>
*/
#include <linux/init.h>
#include <linux/kobject.h>
#include <linux/suspend.h>
#include <linux/sysfs.h>
#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/gpio-au1000.h>
#include <asm/mach-db1x00/bcsr.h>
/*
* Generic suspend userspace interface for Alchemy development boards.
* This code exports a few sysfs nodes under /sys/power/db1x/ which
* can be used by userspace to en/disable all au1x-provided wakeup
* sources and configure the timeout after which the the TOYMATCH2 irq
* is to trigger a wakeup.
*/
static unsigned long db1x_pm_sleep_secs;
static unsigned long db1x_pm_wakemsk;
static unsigned long db1x_pm_last_wakesrc;
static int db1x_pm_enter(suspend_state_t state)
{
unsigned short bcsrs[16];
int i, j, hasint;
/* save CPLD regs */
hasint = bcsr_read(BCSR_WHOAMI);
hasint = BCSR_WHOAMI_BOARD(hasint) >= BCSR_WHOAMI_DB1200;
j = (hasint) ? BCSR_MASKSET : BCSR_SYSTEM;
for (i = BCSR_STATUS; i <= j; i++)
bcsrs[i] = bcsr_read(i);
/* shut off hexleds */
bcsr_write(BCSR_HEXCLEAR, 3);
/* enable GPIO based wakeup */
alchemy_gpio1_input_enable();
/* clear and setup wake cause and source */
alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
alchemy_wrsys(0, AU1000_SYS_WAKESRC);
alchemy_wrsys(db1x_pm_wakemsk, AU1000_SYS_WAKEMSK);
/* setup 1Hz-timer-based wakeup: wait for reg access */
while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
asm volatile ("nop");
alchemy_wrsys(alchemy_rdsys(AU1000_SYS_TOYREAD) + db1x_pm_sleep_secs,
AU1000_SYS_TOYMATCH2);
/* wait for value to really hit the register */
while (alchemy_rdsys(AU1000_SYS_CNTRCTRL) & SYS_CNTRL_M20)
asm volatile ("nop");
/* ...and now the sandman can come! */
au_sleep();
/* restore CPLD regs */
for (i = BCSR_STATUS; i <= BCSR_SYSTEM; i++)
bcsr_write(i, bcsrs[i]);
/* restore CPLD int registers */
if (hasint) {
bcsr_write(BCSR_INTCLR, 0xffff);
bcsr_write(BCSR_MASKCLR, 0xffff);
bcsr_write(BCSR_INTSTAT, 0xffff);
bcsr_write(BCSR_INTSET, bcsrs[BCSR_INTSET]);
bcsr_write(BCSR_MASKSET, bcsrs[BCSR_MASKSET]);
}
/* light up hexleds */
bcsr_write(BCSR_HEXCLEAR, 0);
return 0;
}
static int db1x_pm_begin(suspend_state_t state)
{
if (!db1x_pm_wakemsk) {
printk(KERN_ERR "db1x: no wakeup source activated!\n");
return -EINVAL;
}
return 0;
}
static void db1x_pm_end(void)
{
/* read and store wakeup source, the clear the register. To
* be able to clear it, WAKEMSK must be cleared first.
*/
db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);
alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
alchemy_wrsys(0, AU1000_SYS_WAKESRC);
}
static const struct platform_suspend_ops db1x_pm_ops = {
.valid = suspend_valid_only_mem,
.begin = db1x_pm_begin,
.enter = db1x_pm_enter,
.end = db1x_pm_end,
};
#define ATTRCMP(x) (0 == strcmp(attr->attr.name, #x))
static ssize_t db1x_pmattr_show(struct kobject *kobj,
struct kobj_attribute *attr,
char *buf)
{
int idx;
if (ATTRCMP(timer_timeout))
return sprintf(buf, "%lu\n", db1x_pm_sleep_secs);
else if (ATTRCMP(timer))
return sprintf(buf, "%u\n",
!!(db1x_pm_wakemsk & SYS_WAKEMSK_M2));
else if (ATTRCMP(wakesrc))
return sprintf(buf, "%lu\n", db1x_pm_last_wakesrc);
else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
idx = (attr->attr.name)[4] - '0';
return sprintf(buf, "%d\n",
!!(db1x_pm_wakemsk & SYS_WAKEMSK_GPIO(idx)));
} else if (ATTRCMP(wakemsk)) {
return sprintf(buf, "%08lx\n", db1x_pm_wakemsk);
}
return -ENOENT;
}
static ssize_t db1x_pmattr_store(struct kobject *kobj,
struct kobj_attribute *attr,
const char *instr,
size_t bytes)
{
unsigned long l;
int tmp;
if (ATTRCMP(timer_timeout)) {
tmp = kstrtoul(instr, 0, &l);
if (tmp)
return tmp;
db1x_pm_sleep_secs = l;
} else if (ATTRCMP(timer)) {
if (instr[0] != '0')
db1x_pm_wakemsk |= SYS_WAKEMSK_M2;
else
db1x_pm_wakemsk &= ~SYS_WAKEMSK_M2;
} else if (ATTRCMP(gpio0) || ATTRCMP(gpio1) || ATTRCMP(gpio2) ||
ATTRCMP(gpio3) || ATTRCMP(gpio4) || ATTRCMP(gpio5) ||
ATTRCMP(gpio6) || ATTRCMP(gpio7)) {
tmp = (attr->attr.name)[4] - '0';
if (instr[0] != '0') {
db1x_pm_wakemsk |= SYS_WAKEMSK_GPIO(tmp);
} else {
db1x_pm_wakemsk &= ~SYS_WAKEMSK_GPIO(tmp);
}
} else if (ATTRCMP(wakemsk)) {
tmp = kstrtoul(instr, 0, &l);
if (tmp)
return tmp;
db1x_pm_wakemsk = l & 0x0000003f;
} else
bytes = -ENOENT;
return bytes;
}
#define ATTR(x) \
static struct kobj_attribute x##_attribute = \
__ATTR(x, 0664, db1x_pmattr_show, \
db1x_pmattr_store);
ATTR(gpio0) /* GPIO-based wakeup enable */
ATTR(gpio1)
ATTR(gpio2)
ATTR(gpio3)
ATTR(gpio4)
ATTR(gpio5)
ATTR(gpio6)
ATTR(gpio7)
ATTR(timer) /* TOYMATCH2-based wakeup enable */
ATTR(timer_timeout) /* timer-based wakeup timeout value, in seconds */
ATTR(wakesrc) /* contents of SYS_WAKESRC after last wakeup */
ATTR(wakemsk) /* direct access to SYS_WAKEMSK */
#define ATTR_LIST(x) & x ## _attribute.attr
static struct attribute *db1x_pmattrs[] = {
ATTR_LIST(gpio0),
ATTR_LIST(gpio1),
ATTR_LIST(gpio2),
ATTR_LIST(gpio3),
ATTR_LIST(gpio4),
ATTR_LIST(gpio5),
ATTR_LIST(gpio6),
ATTR_LIST(gpio7),
ATTR_LIST(timer),
ATTR_LIST(timer_timeout),
ATTR_LIST(wakesrc),
ATTR_LIST(wakemsk),
NULL, /* terminator */
};
static struct attribute_group db1x_pmattr_group = {
.name = "db1x",
.attrs = db1x_pmattrs,
};
/*
* Initialize suspend interface
*/
static int __init pm_init(void)
{
/* init TOY to tick at 1Hz if not already done. No need to wait
* for confirmation since there's plenty of time from here to
* the next suspend cycle.
*/
if (alchemy_rdsys(AU1000_SYS_TOYTRIM) != 32767)
alchemy_wrsys(32767, AU1000_SYS_TOYTRIM);
db1x_pm_last_wakesrc = alchemy_rdsys(AU1000_SYS_WAKESRC);
alchemy_wrsys(0, AU1000_SYS_WAKESRC);
alchemy_wrsys(0, AU1000_SYS_WAKEMSK);
suspend_set_ops(&db1x_pm_ops);
return sysfs_create_group(power_kobj, &db1x_pmattr_group);
}
late_initcall(pm_init);