mtd: adapt writebufsize calculation for concat

If different chips with different writebufsize are concatenated,
the writebufsize from the concat device has to be taken from
the device with the largest writebuffer. This writebufsize
is used later on in the UBI layer for the min I/O size.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 5f5777bd3f75f9cb2c9849aa5004174cb1911184..5060e608ea5d40a1fc6307829c31922abb5199a9 100644 (file)
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -750,6 +750,7 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[],       /* subdevices to c
        struct mtd_concat *concat;
        uint32_t max_erasesize, curr_erasesize;
        int num_erase_region;
+       int max_writebufsize = 0;
 
        printk(KERN_NOTICE "Concatenating MTD devices:\n");
        for (i = 0; i < num_devs; i++)
@@ -776,7 +777,12 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[],      /* subdevices to c
        concat->mtd.size = subdev[0]->size;
        concat->mtd.erasesize = subdev[0]->erasesize;
        concat->mtd.writesize = subdev[0]->writesize;
-       concat->mtd.writebufsize = subdev[0]->writebufsize;
+
+       for (i = 0; i < num_devs; i++)
+               if (max_writebufsize < subdev[i]->writebufsize)
+                       max_writebufsize = subdev[i]->writebufsize;
+       concat->mtd.writebufsize = max_writebufsize;
+
        concat->mtd.subpage_sft = subdev[0]->subpage_sft;
        concat->mtd.oobsize = subdev[0]->oobsize;
        concat->mtd.oobavail = subdev[0]->oobavail;