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authorArnd Bergmann <arnd@arndb.de>2011-10-31 14:08:10 +0100
committerArnd Bergmann <arnd@arndb.de>2011-10-31 14:08:10 +0100
commit08cab72f91c8b28ffabfd143119bccdd4a115ad7 (patch)
treeccd5583971caecd82bf2d1e62691bf6e0362d650 /include/linux/cpu_pm.h
parent86c1e5a74af11e4817ffa6d7748d9ac1353b5b53 (diff)
parentf37a53cc5d8a8fb199e41386d125d8c2ed9e54ef (diff)
Merge branch 'dt/gic' into next/dt
Conflicts: arch/arm/include/asm/localtimer.h arch/arm/mach-msm/board-msm8x60.c arch/arm/mach-omap2/board-generic.c
Diffstat (limited to 'include/linux/cpu_pm.h')
-rw-r--r--include/linux/cpu_pm.h109
1 files changed, 109 insertions, 0 deletions
diff --git a/include/linux/cpu_pm.h b/include/linux/cpu_pm.h
new file mode 100644
index 00000000000..455b233dd3b
--- /dev/null
+++ b/include/linux/cpu_pm.h
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Author:
+ * Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#ifndef _LINUX_CPU_PM_H
+#define _LINUX_CPU_PM_H
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+
+/*
+ * When a CPU goes to a low power state that turns off power to the CPU's
+ * power domain, the contents of some blocks (floating point coprocessors,
+ * interrupt controllers, caches, timers) in the same power domain can
+ * be lost. The cpm_pm notifiers provide a method for platform idle, suspend,
+ * and hotplug implementations to notify the drivers for these blocks that
+ * they may be reset.
+ *
+ * All cpu_pm notifications must be called with interrupts disabled.
+ *
+ * The notifications are split into two classes: CPU notifications and CPU
+ * cluster notifications.
+ *
+ * CPU notifications apply to a single CPU and must be called on the affected
+ * CPU. They are used to save per-cpu context for affected blocks.
+ *
+ * CPU cluster notifications apply to all CPUs in a single power domain. They
+ * are used to save any global context for affected blocks, and must be called
+ * after all the CPUs in the power domain have been notified of the low power
+ * state.
+ */
+
+/*
+ * Event codes passed as unsigned long val to notifier calls
+ */
+enum cpu_pm_event {
+ /* A single cpu is entering a low power state */
+ CPU_PM_ENTER,
+
+ /* A single cpu failed to enter a low power state */
+ CPU_PM_ENTER_FAILED,
+
+ /* A single cpu is exiting a low power state */
+ CPU_PM_EXIT,
+
+ /* A cpu power domain is entering a low power state */
+ CPU_CLUSTER_PM_ENTER,
+
+ /* A cpu power domain failed to enter a low power state */
+ CPU_CLUSTER_PM_ENTER_FAILED,
+
+ /* A cpu power domain is exiting a low power state */
+ CPU_CLUSTER_PM_EXIT,
+};
+
+#ifdef CONFIG_CPU_PM
+int cpu_pm_register_notifier(struct notifier_block *nb);
+int cpu_pm_unregister_notifier(struct notifier_block *nb);
+int cpu_pm_enter(void);
+int cpu_pm_exit(void);
+int cpu_cluster_pm_enter(void);
+int cpu_cluster_pm_exit(void);
+
+#else
+
+static inline int cpu_pm_register_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+
+static inline int cpu_pm_unregister_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+
+static inline int cpu_pm_enter(void)
+{
+ return 0;
+}
+
+static inline int cpu_pm_exit(void)
+{
+ return 0;
+}
+
+static inline int cpu_cluster_pm_enter(void)
+{
+ return 0;
+}
+
+static inline int cpu_cluster_pm_exit(void)
+{
+ return 0;
+}
+#endif
+#endif