openwrt_archive/target/linux/generic/patches-3.18/490-ubi-auto-attach-mtd-device-named-ubi-or-data-on-boot.patch
Imre Kaloz 7b966f8ef7 generic: allow ubi autoattach to run on NOR flash
Some devices out there only have a NOR flash to store the rootfs on.
 
While using UBI is arguable on this kind of flash, this is something that should
be supported.
 
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Imre Kaloz <kaloz@openwrt.org>



SVN-Revision: 44260
2015-02-05 11:21:31 +00:00

77 lines
2.1 KiB
Diff

From 8a52e4100d7c3a4a1dfddfa02b8864a9b0068c13 Mon Sep 17 00:00:00 2001
From: Daniel Golle <daniel@makrotopia.org>
Date: Sat, 17 May 2014 03:36:18 +0200
Subject: [PATCH 1/5] ubi: auto-attach mtd device named "ubi" or "data" on boot
To: openwrt-devel@lists.openwrt.org
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
drivers/mtd/ubi/build.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1209,6 +1209,49 @@ static struct mtd_info * __init open_mtd
return mtd;
}
+/*
+ * This function tries attaching mtd partitions named either "ubi" or "data"
+ * during boot.
+ */
+static void __init ubi_auto_attach(void)
+{
+ int err;
+ struct mtd_info *mtd;
+
+ /* try attaching mtd device named "ubi" or "data" */
+ mtd = open_mtd_device("ubi");
+ if (IS_ERR(mtd))
+ mtd = open_mtd_device("data");
+
+ if (!IS_ERR(mtd)) {
+ size_t len;
+ char magic[4];
+
+ /* check for a valid ubi magic */
+ err = mtd_read(mtd, 0, 4, &len, (void *) magic);
+ if (!err && len == 4 && strncmp(magic, "UBI#", 4)) {
+ ubi_err("no valid UBI magic found inside mtd%d", mtd->index);
+ put_mtd_device(mtd);
+ return;
+ }
+
+ /* auto-add only media types where UBI makes sense */
+ if (mtd->type == MTD_NANDFLASH ||
+ mtd->type == MTD_NORFLASH ||
+ mtd->type == MTD_DATAFLASH ||
+ mtd->type == MTD_MLCNANDFLASH) {
+ mutex_lock(&ubi_devices_mutex);
+ ubi_msg("auto-attach mtd%d", mtd->index);
+ err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0);
+ mutex_unlock(&ubi_devices_mutex);
+ if (err < 0) {
+ ubi_err("cannot attach mtd%d", mtd->index);
+ put_mtd_device(mtd);
+ }
+ }
+ }
+}
+
static int __init ubi_init(void)
{
int err, i, k;
@@ -1298,6 +1341,12 @@ static int __init ubi_init(void)
}
}
+ /* auto-attach mtd devices only if built-in to the kernel and no ubi.mtd
+ * parameter was given */
+ if (config_enabled(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
+ !ubi_is_module() && !mtd_devs)
+ ubi_auto_attach();
+
err = ubiblock_init();
if (err) {
ubi_err("block: cannot initialize, error %d", err);