Commit fe0c935a authored by Johannes Berg's avatar Johannes Berg Committed by Linus Torvalds
Browse files

rework pm_ops pm_disk_mode, kill misuse



This patch series cleans up some misconceptions about pm_ops.  Some users of
the pm_ops structure attempt to use it to stop the user from entering suspend
to disk, this, however, is not possible since the user can always use
"shutdown" in /sys/power/disk and then the pm_ops are never invoked.  Also,
platforms that don't support suspend to disk simply should not allow
configuring SOFTWARE_SUSPEND (read the help text on it, it only selects
suspend to disk and nothing else, all the other stuff depends on PM).

The pm_ops structure is actually intended to provide a way to enter
platform-defined sleep states (currently supported states are "standby" and
"mem" (suspend to ram)) and additionally (if SOFTWARE_SUSPEND is configured)
allows a platform to support a platform specific way to enter low-power mode
once everything has been saved to disk.  This is currently only used by ACPI
(S4).

This patch:

The pm_ops.pm_disk_mode is used in totally bogus ways since nobody really
seems to understand what it actually does.

This patch clarifies the pm_disk_mode description.

It also removes all the arm and sh users that think they can veto suspend to
disk via pm_ops; not so since the user can always do echo shutdown >
/sys/power/disk, they need to find a better way involving Kconfig or such.

ACPI is the only user left with a non-zero pm_disk_mode.

The patch also sets the default mode to shutdown again, but when a new pm_ops
is registered its pm_disk_mode is selected as default, that way the default
stays for ACPI where it is apparently required.
Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Acked-by: default avatarRussell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: default avatarPaul Mundt <lethal@linux-sh.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 1173a729
......@@ -766,7 +766,6 @@ static void sharpsl_apm_get_power_status(struct apm_power_info *info)
}
static struct pm_ops sharpsl_pm_ops = {
.pm_disk_mode = PM_DISK_FIRMWARE,
.prepare = pxa_pm_prepare,
.enter = corgi_pxa_pm_enter,
.finish = pxa_pm_finish,
......
......@@ -201,7 +201,6 @@ error:
static struct pm_ops at91_pm_ops ={
.pm_disk_mode = 0,
.valid = at91_pm_valid_state,
.prepare = at91_pm_prepare,
.enter = at91_pm_enter,
......
......@@ -698,7 +698,6 @@ static struct irqaction omap_wakeup_irq = {
static struct pm_ops omap_pm_ops ={
.pm_disk_mode = 0,
.prepare = omap_pm_prepare,
.enter = omap_pm_enter,
.finish = omap_pm_finish,
......
......@@ -370,7 +370,6 @@ static int omap2_pm_finish(suspend_state_t state)
}
static struct pm_ops omap_pm_ops = {
.pm_disk_mode = 0,
.prepare = omap2_pm_prepare,
.enter = omap2_pm_enter,
.finish = omap2_pm_finish,
......
......@@ -223,11 +223,7 @@ int pxa_pm_finish(suspend_state_t state)
EXPORT_SYMBOL_GPL(pxa_pm_finish);
/*
* Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
*/
static struct pm_ops pxa_pm_ops = {
.pm_disk_mode = PM_DISK_FIRMWARE,
.prepare = pxa_pm_prepare,
.enter = pxa_pm_enter,
.finish = pxa_pm_finish,
......
......@@ -59,9 +59,6 @@ static int sa11x0_pm_enter(suspend_state_t state)
unsigned long gpio, sleep_save[SLEEP_SAVE_SIZE];
struct timespec delta, rtc;
if (state != PM_SUSPEND_MEM)
return -EINVAL;
/* preserve current time */
rtc.tv_sec = RCNR;
rtc.tv_nsec = 0;
......@@ -134,11 +131,7 @@ unsigned long sleep_phys_sp(void *sp)
return virt_to_phys(sp);
}
/*
* Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
*/
static struct pm_ops sa11x0_pm_ops = {
.pm_disk_mode = PM_DISK_FIRMWARE,
.enter = sa11x0_pm_enter,
};
......
......@@ -511,11 +511,6 @@ static int s3c2410_pm_enter(suspend_state_t state)
return -EINVAL;
}
if (state != PM_SUSPEND_MEM) {
printk(KERN_ERR PFX "error: only PM_SUSPEND_MEM supported\n");
return -EINVAL;
}
/* check if we have anything to wake-up with... bad things seem
* to happen if you suspend with no wakeup (system will often
* require a full power-cycle)
......@@ -633,11 +628,7 @@ static int s3c2410_pm_finish(suspend_state_t state)
return 0;
}
/*
* Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
*/
static struct pm_ops s3c2410_pm_ops = {
.pm_disk_mode = PM_DISK_FIRMWARE,
.prepare = s3c2410_pm_prepare,
.enter = s3c2410_pm_enter,
.finish = s3c2410_pm_finish,
......
......@@ -27,9 +27,6 @@ static int hp6x0_pm_enter(suspend_state_t state)
u16 hd64461_stbcr;
#endif
if (state != PM_SUSPEND_MEM)
return -EINVAL;
#ifdef CONFIG_HD64461_ENABLER
outb(0, HD64461_PCC1CSCIER);
......@@ -70,11 +67,7 @@ static int hp6x0_pm_enter(suspend_state_t state)
return 0;
}
/*
* Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
*/
static struct pm_ops hp6x0_pm_ops = {
.pm_disk_mode = PM_DISK_FIRMWARE,
.enter = hp6x0_pm_enter,
};
......
......@@ -112,6 +112,8 @@ typedef int __bitwise suspend_state_t;
typedef int __bitwise suspend_disk_method_t;
/* invalid must be 0 so struct pm_ops initialisers can leave it out */
#define PM_DISK_INVALID ((__force suspend_disk_method_t) 0)
#define PM_DISK_FIRMWARE ((__force suspend_disk_method_t) 1)
#define PM_DISK_PLATFORM ((__force suspend_disk_method_t) 2)
#define PM_DISK_SHUTDOWN ((__force suspend_disk_method_t) 3)
......@@ -137,17 +139,16 @@ typedef int __bitwise suspend_disk_method_t;
* @finish: Called when the system has left the given state and all devices
* are resumed. The return value is ignored.
*
* @pm_disk_mode: Set to the disk method that the user should be able to
* configure for suspend-to-disk. Since %PM_DISK_SHUTDOWN,
* %PM_DISK_REBOOT, %PM_DISK_TEST and %PM_DISK_TESTPROC
* are always allowed, currently only %PM_DISK_PLATFORM
* makes sense. If the user then choses %PM_DISK_PLATFORM,
* the @prepare call will be called before suspending to disk
* (if present), the @enter call should be present and will
* be called after all state has been saved and the machine
* is ready to be shut down/suspended/..., and the @finish
* callback is called after state has been restored. All
* these calls are called with %PM_SUSPEND_DISK as the state.
* @pm_disk_mode: The generic code always allows one of the shutdown methods
* %PM_DISK_SHUTDOWN, %PM_DISK_REBOOT, %PM_DISK_TEST and
* %PM_DISK_TESTPROC. If this variable is set, the mode it is set
* to is allowed in addition to those modes and is also made default.
* When this mode is sent selected, the @prepare call will be called
* before suspending to disk (if present), the @enter call should be
* present and will be called after all state has been saved and the
* machine is ready to be powered off; the @finish callback is called
* after state has been restored. All these calls are called with
* %PM_SUSPEND_DISK as the state.
*/
struct pm_ops {
int (*valid)(suspend_state_t state);
......
......@@ -39,7 +39,13 @@ static inline int platform_prepare(void)
{
int error = 0;
if (pm_disk_mode == PM_DISK_PLATFORM) {
switch (pm_disk_mode) {
case PM_DISK_TEST:
case PM_DISK_TESTPROC:
case PM_DISK_SHUTDOWN:
case PM_DISK_REBOOT:
break;
default:
if (pm_ops && pm_ops->prepare)
error = pm_ops->prepare(PM_SUSPEND_DISK);
}
......@@ -48,40 +54,48 @@ static inline int platform_prepare(void)
/**
* power_down - Shut machine down for hibernate.
* @mode: Suspend-to-disk mode
*
* Use the platform driver, if configured so, and return gracefully if it
* fails.
* Otherwise, try to power off and reboot. If they fail, halt the machine,
* there ain't no turning back.
* Use the platform driver, if configured so; otherwise try
* to power off or reboot.
*/
static void power_down(suspend_disk_method_t mode)
static void power_down(void)
{
switch(mode) {
case PM_DISK_PLATFORM:
if (pm_ops && pm_ops->enter) {
kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
pm_ops->enter(PM_SUSPEND_DISK);
break;
}
switch (pm_disk_mode) {
case PM_DISK_TEST:
case PM_DISK_TESTPROC:
break;
case PM_DISK_SHUTDOWN:
kernel_power_off();
break;
case PM_DISK_REBOOT:
kernel_restart(NULL);
break;
default:
if (pm_ops && pm_ops->enter) {
kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
pm_ops->enter(PM_SUSPEND_DISK);
break;
}
}
kernel_halt();
/* Valid image is on the disk, if we continue we risk serious data corruption
after resume. */
/*
* Valid image is on the disk, if we continue we risk serious data
* corruption after resume.
*/
printk(KERN_CRIT "Please power me down manually\n");
while(1);
}
static inline void platform_finish(void)
{
if (pm_disk_mode == PM_DISK_PLATFORM) {
switch (pm_disk_mode) {
case PM_DISK_TEST:
case PM_DISK_TESTPROC:
case PM_DISK_SHUTDOWN:
case PM_DISK_REBOOT:
break;
default:
if (pm_ops && pm_ops->finish)
pm_ops->finish(PM_SUSPEND_DISK);
}
......@@ -166,7 +180,7 @@ int pm_suspend_disk(void)
pr_debug("PM: writing image.\n");
error = swsusp_write();
if (!error)
power_down(pm_disk_mode);
power_down();
else {
swsusp_free();
goto Thaw;
......@@ -338,10 +352,14 @@ static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
}
}
if (mode) {
if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT ||
mode == PM_DISK_TEST || mode == PM_DISK_TESTPROC) {
switch (mode) {
case PM_DISK_SHUTDOWN:
case PM_DISK_REBOOT:
case PM_DISK_TEST:
case PM_DISK_TESTPROC:
pm_disk_mode = mode;
} else {
break;
default:
if (pm_ops && pm_ops->enter &&
(mode == pm_ops->pm_disk_mode))
pm_disk_mode = mode;
......
......@@ -30,7 +30,7 @@
DEFINE_MUTEX(pm_mutex);
struct pm_ops *pm_ops;
suspend_disk_method_t pm_disk_mode = PM_DISK_PLATFORM;
suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN;
/**
* pm_set_ops - Set the global power method table.
......@@ -41,6 +41,10 @@ void pm_set_ops(struct pm_ops * ops)
{
mutex_lock(&pm_mutex);
pm_ops = ops;
if (ops && ops->pm_disk_mode != PM_DISK_INVALID) {
pm_disk_mode = ops->pm_disk_mode;
} else
pm_disk_mode = PM_DISK_SHUTDOWN;
mutex_unlock(&pm_mutex);
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment