1 files changed, 78 insertions, 15 deletions

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index c4d26de74349..7070110aba2a 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -15,6 +15,7 @@
 #include <linux/timer.h>
 #include <linux/major.h>
 #include <linux/fs.h>
+#include <linux/err.h>
 #include <linux/ioctl.h>
 #include <linux/init.h>
 #include <linux/mtd/compatmac.h>
@@ -192,14 +193,14 @@ int unregister_mtd_user (struct mtd_notifier *old)
  *      Given a number and NULL address, return the num'th entry in the device
  *      table, if any.  Given an address and num == -1, search the device table
  *      for a device with that address and return if it's still present. Given
- *      both, return the num'th driver only if its address matches. Return NULL
- *      if not.
+ *      both, return the num'th driver only if its address matches. Return
+ *      error code if not.
  */
 
 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
 {
         struct mtd_info *ret = NULL;
-        int i;
+        int i, err = -ENODEV;
 
         mutex_lock(&mtd_table_mutex);
 
@@ -213,14 +214,73 @@ struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
                         ret = NULL;
         }
 
-        if (ret && !try_module_get(ret->owner))
-                ret = NULL;
+        if (!ret)
+                goto out_unlock;
+
+        if (!try_module_get(ret->owner))
+                goto out_unlock;
 
-        if (ret)
-                ret->usecount++;
+        if (ret->get_device) {
+                err = ret->get_device(ret);
+                if (err)
+                        goto out_put;
+        }
 
+        ret->usecount++;
         mutex_unlock(&mtd_table_mutex);
         return ret;
+
+out_put:
+        module_put(ret->owner);
+out_unlock:
+        mutex_unlock(&mtd_table_mutex);
+        return ERR_PTR(err);
+}
+
+/**
+ *      get_mtd_device_nm - obtain a validated handle for an MTD device by
+ *      device name
+ *      @name: MTD device name to open
+ *
+ *      This function returns MTD device description structure in case of
+ *      success and an error code in case of failure.
+ */
+
+struct mtd_info *get_mtd_device_nm(const char *name)
+{
+        int i, err = -ENODEV;
+        struct mtd_info *mtd = NULL;
+
+        mutex_lock(&mtd_table_mutex);
+
+        for (i = 0; i < MAX_MTD_DEVICES; i++) {
+                if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) {
+                        mtd = mtd_table[i];
+                        break;
+                }
+        }
+
+        if (!mtd)
+                goto out_unlock;
+
+        if (!try_module_get(mtd->owner))
+                goto out_unlock;
+
+        if (mtd->get_device) {
+                err = mtd->get_device(mtd);
+                if (err)
+                        goto out_put;
+        }
+
+        mtd->usecount++;
+        mutex_unlock(&mtd_table_mutex);
+        return mtd;
+
+out_put:
+        module_put(mtd->owner);
+out_unlock:
+        mutex_unlock(&mtd_table_mutex);
+        return ERR_PTR(err);
 }
 
 void put_mtd_device(struct mtd_info *mtd)
@@ -229,6 +289,8 @@ void put_mtd_device(struct mtd_info *mtd)
 
         mutex_lock(&mtd_table_mutex);
         c = --mtd->usecount;
+        if (mtd->put_device)
+                mtd->put_device(mtd);
         mutex_unlock(&mtd_table_mutex);
         BUG_ON(c < 0);
 
@@ -236,7 +298,7 @@ void put_mtd_device(struct mtd_info *mtd)
 }
 
 /* default_mtd_writev - default mtd writev method for MTD devices that
- *                      dont implement their own
+ *                      don't implement their own
  */
 
 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
@@ -264,13 +326,14 @@ int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
         return ret;
 }
 
-EXPORT_SYMBOL(add_mtd_device);
-EXPORT_SYMBOL(del_mtd_device);
-EXPORT_SYMBOL(get_mtd_device);
-EXPORT_SYMBOL(put_mtd_device);
-EXPORT_SYMBOL(register_mtd_user);
-EXPORT_SYMBOL(unregister_mtd_user);
-EXPORT_SYMBOL(default_mtd_writev);
+EXPORT_SYMBOL_GPL(add_mtd_device);
+EXPORT_SYMBOL_GPL(del_mtd_device);
+EXPORT_SYMBOL_GPL(get_mtd_device);
+EXPORT_SYMBOL_GPL(get_mtd_device_nm);
+EXPORT_SYMBOL_GPL(put_mtd_device);
+EXPORT_SYMBOL_GPL(register_mtd_user);
+EXPORT_SYMBOL_GPL(unregister_mtd_user);
+EXPORT_SYMBOL_GPL(default_mtd_writev);
 
 #ifdef CONFIG_PROC_FS