From: Johannes Berg 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: Johannes Berg Cc: David Brownell Acked-by: Pavel Machek Cc: Cc: Len Brown Acked-by: Russell King Cc: Greg KH Cc: "Rafael J. Wysocki" Acked-by: Paul Mundt Signed-off-by: Andrew Morton --- arch/arm/common/sharpsl_pm.c | 1 arch/arm/mach-at91/pm.c | 1 arch/arm/mach-omap1/pm.c | 1 arch/arm/mach-omap2/pm.c | 1 arch/arm/mach-pxa/pm.c | 4 -- arch/arm/mach-sa1100/pm.c | 7 --- arch/arm/plat-s3c24xx/pm.c | 9 ---- arch/sh/boards/hp6xx/pm.c | 7 --- include/linux/pm.h | 23 ++++++------ kernel/power/disk.c | 60 +++++++++++++++++++++------------ kernel/power/main.c | 6 ++- 11 files changed, 56 insertions(+), 64 deletions(-) diff -puN arch/arm/common/sharpsl_pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/common/sharpsl_pm.c --- a/arch/arm/common/sharpsl_pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/common/sharpsl_pm.c @@ -766,7 +766,6 @@ static void sharpsl_apm_get_power_status } 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, diff -puN arch/arm/mach-at91/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/mach-at91/pm.c --- a/arch/arm/mach-at91/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/mach-at91/pm.c @@ -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, diff -puN arch/arm/mach-omap1/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/mach-omap1/pm.c --- a/arch/arm/mach-omap1/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/mach-omap1/pm.c @@ -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, diff -puN arch/arm/mach-omap2/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/mach-omap2/pm.c --- a/arch/arm/mach-omap2/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/mach-omap2/pm.c @@ -370,7 +370,6 @@ static int omap2_pm_finish(suspend_state } static struct pm_ops omap_pm_ops = { - .pm_disk_mode = 0, .prepare = omap2_pm_prepare, .enter = omap2_pm_enter, .finish = omap2_pm_finish, diff -puN arch/arm/mach-pxa/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/mach-pxa/pm.c --- a/arch/arm/mach-pxa/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/mach-pxa/pm.c @@ -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, diff -puN arch/arm/mach-sa1100/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/mach-sa1100/pm.c --- a/arch/arm/mach-sa1100/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/mach-sa1100/pm.c @@ -59,9 +59,6 @@ static int sa11x0_pm_enter(suspend_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, }; diff -puN arch/arm/plat-s3c24xx/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/arm/plat-s3c24xx/pm.c --- a/arch/arm/plat-s3c24xx/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/arm/plat-s3c24xx/pm.c @@ -511,11 +511,6 @@ static int s3c2410_pm_enter(suspend_stat 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_sta 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, diff -puN arch/sh/boards/hp6xx/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse arch/sh/boards/hp6xx/pm.c --- a/arch/sh/boards/hp6xx/pm.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/arch/sh/boards/hp6xx/pm.c @@ -27,9 +27,6 @@ static int hp6x0_pm_enter(suspend_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_ 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, }; diff -puN include/linux/pm.h~rework-pm_ops-pm_disk_mode-kill-misuse include/linux/pm.h --- a/include/linux/pm.h~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/include/linux/pm.h @@ -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_metho * @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); diff -puN kernel/power/disk.c~rework-pm_ops-pm_disk_mode-kill-misuse kernel/power/disk.c --- a/kernel/power/disk.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/kernel/power/disk.c @@ -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); } @@ -176,7 +190,7 @@ 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; @@ -364,10 +378,14 @@ static ssize_t disk_store(struct subsyst } } 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; diff -puN kernel/power/main.c~rework-pm_ops-pm_disk_mode-kill-misuse kernel/power/main.c --- a/kernel/power/main.c~rework-pm_ops-pm_disk_mode-kill-misuse +++ a/kernel/power/main.c @@ -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); } _