kernel: copy kernel 4.19 code to 5.4

No changes were done to the patches while coping them. Currently they do
not apply on top of kernel 5.4.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 97 insertions, 0 deletions

diff --git a/target/linux/generic/pending-5.4/490-ubi-auto-attach-mtd-device-named-ubi-or-data-on-boot.patch b/target/linux/generic/pending-5.4/490-ubi-auto-attach-mtd-device-named-ubi-or-data-on-boot.patch
new file mode 100644
index 0000000000..79d18d036f
--- /dev/null
+++ b/target/linux/generic/pending-5.4/490-ubi-auto-attach-mtd-device-named-ubi-or-data-on-boot.patch
@@ -0,0 +1,97 @@
+From: Daniel Golle <daniel@makrotopia.org>
+Subject: ubi: auto-attach mtd device named "ubi" or "data" on boot
+
+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
+@@ -1181,6 +1181,73 @@ 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;
++	loff_t offset = 0;
++	size_t len;
++	char magic[4];
++
++	/* 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))
++		return;
++
++	/* get the first not bad block */
++	if (mtd_can_have_bb(mtd))
++		while (mtd_block_isbad(mtd, offset)) {
++			offset += mtd->erasesize;
++
++			if (offset > mtd->size) {
++				pr_err("UBI error: Failed to find a non-bad "
++				       "block on mtd%d\n", mtd->index);
++				goto cleanup;
++			}
++		}
++
++	/* check if the read from flash was successful */
++	err = mtd_read(mtd, offset, 4, &len, (void *) magic);
++	if ((err && !mtd_is_bitflip(err)) || len != 4) {
++		pr_err("UBI error: unable to read from mtd%d\n", mtd->index);
++		goto cleanup;
++	}
++
++	/* check for a valid ubi magic */
++	if (strncmp(magic, "UBI#", 4)) {
++		pr_err("UBI error: no valid UBI magic found inside mtd%d\n", mtd->index);
++		goto cleanup;
++	}
++
++	/* don't auto-add media types where UBI doesn't makes sense */
++	if (mtd->type != MTD_NANDFLASH &&
++	    mtd->type != MTD_NORFLASH &&
++	    mtd->type != MTD_DATAFLASH &&
++	    mtd->type != MTD_MLCNANDFLASH)
++		goto cleanup;
++
++	mutex_lock(&ubi_devices_mutex);
++	pr_notice("UBI: auto-attach mtd%d\n", mtd->index);
++	err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0);
++	mutex_unlock(&ubi_devices_mutex);
++	if (err < 0) {
++		pr_err("UBI error: cannot attach mtd%d\n", mtd->index);
++		goto cleanup;
++	}
++
++	return;
++
++cleanup:
++	put_mtd_device(mtd);
++}
++
+ static int __init ubi_init(void)
+ {
+ 	int err, i, k;
+@@ -1264,6 +1331,12 @@ 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 (IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
++	    !ubi_is_module() && !mtd_devs)
++		ubi_auto_attach();
++
+ 	err = ubiblock_init();
+ 	if (err) {
+ 		pr_err("UBI error: block: cannot initialize, error %d\n", err);