kernel: bump 4.9 to 4.9.96
[openwrt/staging/wigyori.git] / target / linux / generic / pending-4.9 / 490-ubi-auto-attach-mtd-device-named-ubi-or-data-on-boot.patch
1 From: Daniel Golle <daniel@makrotopia.org>
2 Subject: ubi: auto-attach mtd device named "ubi" or "data" on boot
3
4 Signed-off-by: Daniel Golle <daniel@makrotopia.org>
5 ---
6 drivers/mtd/ubi/build.c | 36 ++++++++++++++++++++++++++++++++++++
7 1 file changed, 36 insertions(+)
8
9 --- a/drivers/mtd/ubi/build.c
10 +++ b/drivers/mtd/ubi/build.c
11 @@ -1223,6 +1223,49 @@ static struct mtd_info * __init open_mtd
12 return mtd;
13 }
14
15 +/*
16 + * This function tries attaching mtd partitions named either "ubi" or "data"
17 + * during boot.
18 + */
19 +static void __init ubi_auto_attach(void)
20 +{
21 + int err;
22 + struct mtd_info *mtd;
23 +
24 + /* try attaching mtd device named "ubi" or "data" */
25 + mtd = open_mtd_device("ubi");
26 + if (IS_ERR(mtd))
27 + mtd = open_mtd_device("data");
28 +
29 + if (!IS_ERR(mtd)) {
30 + size_t len;
31 + char magic[4];
32 +
33 + /* check for a valid ubi magic */
34 + err = mtd_read(mtd, 0, 4, &len, (void *) magic);
35 + if (!err && len == 4 && strncmp(magic, "UBI#", 4)) {
36 + pr_err("UBI error: no valid UBI magic found inside mtd%d\n", mtd->index);
37 + put_mtd_device(mtd);
38 + return;
39 + }
40 +
41 + /* auto-add only media types where UBI makes sense */
42 + if (mtd->type == MTD_NANDFLASH ||
43 + mtd->type == MTD_NORFLASH ||
44 + mtd->type == MTD_DATAFLASH ||
45 + mtd->type == MTD_MLCNANDFLASH) {
46 + mutex_lock(&ubi_devices_mutex);
47 + pr_notice("UBI: auto-attach mtd%d\n", mtd->index);
48 + err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0);
49 + mutex_unlock(&ubi_devices_mutex);
50 + if (err < 0) {
51 + pr_err("UBI error: cannot attach mtd%d\n", mtd->index);
52 + put_mtd_device(mtd);
53 + }
54 + }
55 + }
56 +}
57 +
58 static int __init ubi_init(void)
59 {
60 int err, i, k;
61 @@ -1306,6 +1349,12 @@ static int __init ubi_init(void)
62 }
63 }
64
65 + /* auto-attach mtd devices only if built-in to the kernel and no ubi.mtd
66 + * parameter was given */
67 + if (IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
68 + !ubi_is_module() && !mtd_devs)
69 + ubi_auto_attach();
70 +
71 err = ubiblock_init();
72 if (err) {
73 pr_err("UBI error: block: cannot initialize, error %d", err);