firmware loader: cache devices firmware during suspend/resume cycle
This patch implements caching devices' firmware automatically
during system syspend/resume cycle, so any device drivers can
call request_firmware or request_firmware_nowait inside resume
path to get the cached firmware if they have loaded firmwares
successfully at least once before entering suspend.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 8ca0052..5bd2100a 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -24,6 +24,7 @@
#include <linux/list.h>
#include <linux/async.h>
#include <linux/pm.h>
+#include <linux/suspend.h>
#include "base.h"
#include "power/power.h"
@@ -108,6 +109,8 @@
wait_queue_head_t wait_queue;
int cnt;
struct delayed_work work;
+
+ struct notifier_block pm_notify;
};
struct firmware_buf {
@@ -1217,6 +1220,31 @@
msecs_to_jiffies(delay));
}
+#ifdef CONFIG_PM
+static int fw_pm_notify(struct notifier_block *notify_block,
+ unsigned long mode, void *unused)
+{
+ switch (mode) {
+ case PM_HIBERNATION_PREPARE:
+ case PM_SUSPEND_PREPARE:
+ device_cache_fw_images();
+ break;
+
+ case PM_POST_SUSPEND:
+ case PM_POST_HIBERNATION:
+ case PM_POST_RESTORE:
+ device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
+ break;
+ }
+
+ return 0;
+}
+#else
+static int fw_pm_notify(struct notifier_block *notify_block,
+ unsigned long mode, void *unused)
+{}
+#endif
+
static void __init fw_cache_init(void)
{
spin_lock_init(&fw_cache.lock);
@@ -1229,6 +1257,9 @@
init_waitqueue_head(&fw_cache.wait_queue);
INIT_DELAYED_WORK(&fw_cache.work,
device_uncache_fw_images_work);
+
+ fw_cache.pm_notify.notifier_call = fw_pm_notify;
+ register_pm_notifier(&fw_cache.pm_notify);
}
static int __init firmware_class_init(void)
@@ -1239,6 +1270,7 @@
static void __exit firmware_class_exit(void)
{
+ unregister_pm_notifier(&fw_cache.pm_notify);
class_unregister(&firmware_class);
}