1 files changed, 43 insertions, 15 deletions

diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index 66f0405f7e53..b16f3cda97ff 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -9,7 +9,15 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+/*
+ * When the first attempt at device initialization fails, we may need to
+ * wait a little bit and retry. This timeout, by default 3 seconds, gives
+ * device time to start up. Required on BCM2708 and a few other chipsets.
+ */
+#define MTD_DEFAULT_TIMEOUT	3
+
 #include <linux/module.h>
+#include <linux/delay.h>
 #include <linux/fs.h>
 #include <linux/blkdev.h>
 #include <linux/bio.h>
@@ -209,10 +217,14 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
 }
 
 
-static struct block2mtd_dev *add_device(char *devname, int erase_size)
+static struct block2mtd_dev *add_device(char *devname, int erase_size,
+		int timeout)
 {
+#ifndef MODULE
+	int i;
+#endif
 	const fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL;
-	struct block_device *bdev;
+	struct block_device *bdev = ERR_PTR(-ENODEV);
 	struct block2mtd_dev *dev;
 	char *name;
 
@@ -225,15 +237,28 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size)
 
 	/* Get a handle on the device */
 	bdev = blkdev_get_by_path(devname, mode, dev);
-#ifndef MODULE
-	if (IS_ERR(bdev)) {
-
-		/* We might not have rootfs mounted at this point. Try
-		   to resolve the device name by other means. */
 
-		dev_t devt = name_to_dev_t(devname);
-		if (devt)
-			bdev = blkdev_get_by_dev(devt, mode, dev);
+#ifndef MODULE
+	/*
+	 * We might not have the root device mounted at this point.
+	 * Try to resolve the device name by other means.
+	 */
+	for (i = 0; IS_ERR(bdev) && i <= timeout; i++) {
+		dev_t devt;
+
+		if (i)
+			/*
+			 * Calling wait_for_device_probe in the first loop
+			 * was not enough, sleep for a bit in subsequent
+			 * go-arounds.
+			 */
+			msleep(1000);
+		wait_for_device_probe();
+
+		devt = name_to_dev_t(devname);
+		if (!devt)
+			continue;
+		bdev = blkdev_get_by_dev(devt, mode, dev);
 	}
 #endif
 
@@ -280,6 +305,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size)
 		/* Device didn't get added, so free the entry */
 		goto err_destroy_mutex;
 	}
+
 	list_add(&dev->list, &blkmtd_device_list);
 	pr_info("mtd%d: [%s] erase_size = %dKiB [%d]\n",
 		dev->mtd.index,
@@ -348,16 +374,19 @@ static inline void kill_final_newline(char *str)
 
 #ifndef MODULE
 static int block2mtd_init_called = 0;
-static char block2mtd_paramline[80 + 12]; /* 80 for device, 12 for erase size */
+/* 80 for device, 12 for erase size */
+static char block2mtd_paramline[80 + 12];
 #endif
 
 static int block2mtd_setup2(const char *val)
 {
-	char buf[80 + 12]; /* 80 for device, 12 for erase size */
+	/* 80 for device, 12 for erase size, 80 for name, 8 for timeout */
+	char buf[80 + 12 + 80 + 8];
 	char *str = buf;
 	char *token[2];
 	char *name;
 	size_t erase_size = PAGE_SIZE;
+	unsigned long timeout = MTD_DEFAULT_TIMEOUT;
 	int i, ret;
 
 	if (strnlen(val, sizeof(buf)) >= sizeof(buf)) {
@@ -395,7 +424,7 @@ static int block2mtd_setup2(const char *val)
 		}
 	}
 
-	add_device(name, erase_size);
+	add_device(name, erase_size, timeout);
 
 	return 0;
 }
@@ -463,8 +492,7 @@ static void block2mtd_exit(void)
 	}
 }
 
-
-module_init(block2mtd_init);
+late_initcall(block2mtd_init);
 module_exit(block2mtd_exit);
 
 MODULE_LICENSE("GPL");