mtd: implement common reboot notifier boilerplate

cfi_cmdset_000{1,2}.c already implement their own reboot notifiers, and
we're going to add one for NAND. Let's put the boilerplate in one place.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Scott Branden <sbranden@broadcom.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 4c611871d7e6..cbc0fc46d2d6 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -37,6 +37,7 @@
 #include <linux/backing-dev.h>
 #include <linux/gfp.h>
 #include <linux/slab.h>
+#include <linux/reboot.h>
 
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
@@ -365,6 +366,17 @@ static struct device_type mtd_devtype = {
         .release        = mtd_release,
 };
 
+static int mtd_reboot_notifier(struct notifier_block *n, unsigned long state,
+                               void *cmd)
+{
+        struct mtd_info *mtd;
+
+        mtd = container_of(n, struct mtd_info, reboot_notifier);
+        mtd->_reboot(mtd);
+
+        return NOTIFY_DONE;
+}
+
 /**
  *      add_mtd_device - register an MTD device
  *      @mtd: pointer to new MTD device info structure
@@ -565,6 +577,11 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
                         err = -ENODEV;
         }
 
+        if (mtd->_reboot) {
+                mtd->reboot_notifier.notifier_call = mtd_reboot_notifier;
+                register_reboot_notifier(&mtd->reboot_notifier);
+        }
+
         return err;
 }
 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
@@ -579,6 +596,9 @@ int mtd_device_unregister(struct mtd_info *master)
 {
         int err;
 
+        if (master->_reboot)
+                unregister_reboot_notifier(&master->reboot_notifier);
+
         err = del_mtd_partitions(master);
         if (err)
                 return err;