[PATCH 1/2] PM: Remove legacy PM

Rafael J. Wysocki
2008-03-13T22:52:49Z

From: Pavel Machek <pavel@suse.cz>

AFAICT pm_send_all is a nop when noone uses pm_register...

Hmm.. can we just force CONFIG_PM_LEGACY=n, and see what happens?

Or maybe this is better idea? It may break build somewhere, but it
should be easy to fix... (it builds here, i386 and x86-64).

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
arch/frv/kernel/pm.c | 8 -
arch/mips/au1000/common/power.c | 17 ---
arch/x86/kernel/apm_32.c | 15 --
kernel/power/Kconfig | 10 -
kernel/power/Makefile | 1
kernel/power/pm.c | 205 ----------------------------------------
6 files changed, 2 insertions(+), 254 deletions(-)

Index: linux-2.6/arch/frv/kernel/pm.c
===================================================================
--- linux-2.6.orig/arch/frv/kernel/pm.c
+++ linux-2.6/arch/frv/kernel/pm.c
@@ -163,14 +163,11 @@ static int sysctl_pm_do_suspend(ctl_tabl
if ((mode != 1) && (mode != 5))
return -EINVAL;

- retval = pm_send_all(PM_SUSPEND, (void *)3);
-
if (retval == 0) {
if (mode == 5)
retval = pm_do_bus_sleep();
else
retval = pm_do_suspend();
- pm_send_all(PM_RESUME, (void *)0);
}

return retval;
@@ -183,9 +180,6 @@ static int try_set_cmode(int new_cmode)
if (!(clock_cmodes_permitted & (1<<new_cmode)))
return -EINVAL;

- /* tell all the drivers we're suspending */
- pm_send_all(PM_SUSPEND, (void *)3);
-
/* now change cmode */
local_irq_disable();
frv_dma_pause_all();
@@ -201,8 +195,6 @@ static int try_set_cmode(int new_cmode)
frv_dma_resume_all();
local_irq_enable();

- /* tell all the drivers we're resuming */
- pm_send_all(PM_RESUME, (void *)0);
return 0;
}

Index: linux-2.6/arch/mips/au1000/common/power.c
===================================================================
--- linux-2.6.orig/arch/mips/au1000/common/power.c
+++ linux-2.6/arch/mips/au1000/common/power.c
@@ -258,7 +258,6 @@ int au_sleep(void)
static int pm_do_sleep(ctl_table * ctl, int write, struct file *file,
void __user *buffer, size_t * len, loff_t *ppos)
{
- int retval = 0;
#ifdef SLEEP_TEST_TIMEOUT
#define TMPBUFLEN2 16
char buf[TMPBUFLEN2], *p;
@@ -278,33 +277,21 @@ static int pm_do_sleep(ctl_table * ctl,
p = buf;
sleep_ticks = simple_strtoul(p, &p, 0);
#endif
- retval = pm_send_all(PM_SUSPEND, (void *) 2);
-
- if (retval)
- return retval;

au_sleep();
- retval = pm_send_all(PM_RESUME, (void *) 0);
}
- return retval;
+ return 0;
}

static int pm_do_suspend(ctl_table * ctl, int write, struct file *file,
void __user *buffer, size_t * len, loff_t *ppos)
{
- int retval = 0;
-
if (!write) {
*len = 0;
} else {
- retval = pm_send_all(PM_SUSPEND, (void *) 2);
- if (retval)
- return retval;
suspend_mode = 1;
-
- retval = pm_send_all(PM_RESUME, (void *) 0);
}
- return retval;
+ return 0;
}

Index: linux-2.6/arch/x86/kernel/apm_32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/apm_32.c
+++ linux-2.6/arch/x86/kernel/apm_32.c
@@ -1189,19 +1189,6 @@ static int suspend(int vetoable)
int err;
struct apm_user *as;

- if (pm_send_all(PM_SUSPEND, (void *)3)) {
- /* Vetoed */
- if (vetoable) {
- if (apm_info.connection_version > 0x100)
- set_system_power_state(APM_STATE_REJECT);
- err = -EBUSY;
- ignore_sys_suspend = 0;
- printk(KERN_WARNING "apm: suspend was vetoed.\n");
- goto out;
- }
- printk(KERN_CRIT "apm: suspend was vetoed, but suspending anyway.\n");
- }
-
device_suspend(PMSG_SUSPEND);
local_irq_disable();
device_power_down(PMSG_SUSPEND);
@@ -1224,7 +1211,6 @@ static int suspend(int vetoable)
device_power_up();
local_irq_enable();
device_resume();
- pm_send_all(PM_RESUME, (void *)0);
queue_event(APM_NORMAL_RESUME, NULL);
out:
spin_lock(&user_list_lock);
@@ -1337,7 +1323,6 @@ static void check_events(void)
if ((event != APM_NORMAL_RESUME)
|| (ignore_normal_resume == 0)) {
device_resume();
- pm_send_all(PM_RESUME, (void *)0);
queue_event(event, NULL);
}
ignore_normal_resume = 0;
Index: linux-2.6/kernel/power/Kconfig
===================================================================
--- linux-2.6.orig/kernel/power/Kconfig
+++ linux-2.6/kernel/power/Kconfig
@@ -19,16 +19,6 @@ config PM
will issue the hlt instruction if nothing is to be done, thereby
sending the processor to sleep and saving power.

-config PM_LEGACY
- bool "Legacy Power Management API (DEPRECATED)"
- depends on PM
- default n
- ---help---
- Support for pm_register() and friends. This old API is obsoleted
- by the driver model.
-
- If unsure, say N.
-
config PM_DEBUG
bool "Power Management Debug Support"
depends on PM
Index: linux-2.6/kernel/power/Makefile
===================================================================
--- linux-2.6.orig/kernel/power/Makefile
+++ linux-2.6/kernel/power/Makefile
@@ -4,7 +4,6 @@ EXTRA_CFLAGS += -DDEBUG
endif

obj-y := main.o
-obj-$(CONFIG_PM_LEGACY) += pm.o
obj-$(CONFIG_PM_SLEEP) += process.o console.o
obj-$(CONFIG_HIBERNATION) += swsusp.o disk.o snapshot.o swap.o user.o

Index: linux-2.6/kernel/power/pm.c
===================================================================
--- linux-2.6.orig/kernel/power/pm.c
+++ /dev/null
@@ -1,205 +0,0 @@
-/*
- * pm.c - Power management interface
- *
- * Copyright (C) 2000 Andrew Henroid
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/pm.h>
-#include <linux/pm_legacy.h>
-#include <linux/interrupt.h>
-#include <linux/mutex.h>
-
-/*
- * Locking notes:
- * pm_devs_lock can be a semaphore providing pm ops are not called
- * from an interrupt handler (already a bad idea so no change here). Each
- * change must be protected so that an unlink of an entry doesn't clash
- * with a pm send - which is permitted to sleep in the current architecture
- *
- * Module unloads clashing with pm events now work out safely, the module
- * unload path will block until the event has been sent. It may well block
- * until a resume but that will be fine.
- */
-
-static DEFINE_MUTEX(pm_devs_lock);
-static LIST_HEAD(pm_devs);
-
-/**
- * pm_register - register a device with power management
- * @type: device type
- * @id: device ID
- * @callback: callback function
- *
- * Add a device to the list of devices that wish to be notified about
- * power management events. A &pm_dev structure is returned on success,
- * on failure the return is %NULL.
- *
- * The callback function will be called in process context and
- * it may sleep.
- */
-
-struct pm_dev *pm_register(pm_dev_t type,
- unsigned long id,
- pm_callback callback)
-{
- struct pm_dev *dev = kzalloc(sizeof(struct pm_dev), GFP_KERNEL);
- if (dev) {
- dev->type = type;
- dev->id = id;
- dev->callback = callback;
-
- mutex_lock(&pm_devs_lock);
- list_add(&dev->entry, &pm_devs);
- mutex_unlock(&pm_devs_lock);
- }
- return dev;
-}
-
-/**
- * pm_send - send request to a single device
- * @dev: device to send to
- * @rqst: power management request
- * @data: data for the callback
- *
- * Issue a power management request to a given device. The
- * %PM_SUSPEND and %PM_RESUME events are handled specially. The
- * data field must hold the intended next state. No call is made
- * if the state matches.
- *
- * BUGS: what stops two power management requests occurring in parallel
- * and conflicting.
- *
- * WARNING: Calling pm_send directly is not generally recommended, in
- * particular there is no locking against the pm_dev going away. The
- * caller must maintain all needed locking or have 'inside knowledge'
- * on the safety. Also remember that this function is not locked against
- * pm_unregister. This means that you must handle SMP races on callback
- * execution and unload yourself.
- */
-
-static int pm_send(struct pm_dev *dev, pm_request_t rqst, void *data)
-{
- int status = 0;
- unsigned long prev_state, next_state;
-
- if (in_interrupt())
- BUG();
-
- switch (rqst) {
- case PM_SUSPEND:
- case PM_RESUME:
- prev_state = dev->state;
- next_state = (unsigned long) data;
- if (prev_state != next_state) {
- if (dev->callback)
- status = (*dev->callback)(dev, rqst, data);
- if (!status) {
- dev->state = next_state;
- dev->prev_state = prev_state;
- }
- }
- else {
- dev->prev_state = prev_state;
- }
- break;
- default:
- if (dev->callback)
- status = (*dev->callback)(dev, rqst, data);
- break;
- }
- return status;
-}
-
-/*
- * Undo incomplete request
- */
-static void pm_undo_all(struct pm_dev *last)
-{
- struct list_head *entry = last->entry.prev;
- while (entry != &pm_devs) {
- struct pm_dev *dev = list_entry(entry, struct pm_dev, entry);
- if (dev->state != dev->prev_state) {
- /* previous state was zero (running) resume or
- * previous state was non-zero (suspended) suspend
- */
- pm_request_t undo = (dev->prev_state
- ? PM_SUSPEND:PM_RESUME);
- pm_send(dev, undo, (void*) dev->prev_state);
- }
- entry = entry->prev;
- }
-}
-
-/**
- * pm_send_all - send request to all managed devices
- * @rqst: power management request
- * @data: data for the callback
- *
- * Issue a power management request to a all devices. The
- * %PM_SUSPEND events are handled specially. Any device is
- * permitted to fail a suspend by returning a non zero (error)
- * value from its callback function. If any device vetoes a
- * suspend request then all other devices that have suspended
- * during the processing of this request are restored to their
- * previous state.
- *
- * WARNING: This function takes the pm_devs_lock. The lock is not dropped until
- * the callbacks have completed. This prevents races against pm locking
- * functions, races against module unload pm_unregister code. It does
- * mean however that you must not issue pm_ functions within the callback
- * or you will deadlock and users will hate you.
- *
- * Zero is returned on success. If a suspend fails then the status
- * from the device that vetoes the suspend is returned.
- *
- * BUGS: what stops two power management requests occurring in parallel
- * and conflicting.
- */
-
-int pm_send_all(pm_request_t rqst, void *data)
-{
- struct list_head *entry;
-
- mutex_lock(&pm_devs_lock);
- entry = pm_devs.next;
- while (entry != &pm_devs) {
- struct pm_dev *dev = list_entry(entry, struct pm_dev, entry);
- if (dev->callback) {
- int status = pm_send(dev, rqst, data);
- if (status) {
- /* return devices to previous state on
- * failed suspend request
- */
- if (rqst == PM_SUSPEND)
- pm_undo_all(dev);
- mutex_unlock(&pm_devs_lock);
- return status;
- }
- }
- entry = entry->next;
- }
- mutex_unlock(&pm_devs_lock);
- return 0;
-}
-
-EXPORT_SYMBOL(pm_register);
-EXPORT_SYMBOL(pm_send_all);
-