mtd: add logic for TP-Link ramips recovery magic

This adds an option to set the recovery flag of newer TP-Link MediaTek
boards and remove it after a successful write.

To make use of this feature, add the '-t' option to mtd-write.

The '-t' option takes the mtd partition containing the recovery flag
(usually 'romfile') as an argument. Make sure this partition is not
flagged as read-only!

Example:
 > mtd -t romfile write owrt.bin firmware

This command writes the recovery-flag before it begins writing the image
to the firmware partition. After the image-write has been successful,
the recovery flag is removed.

This way, the TP-Link web-recovery is automatically enabled on an
unsucessful flash (e.g. power loss).

This option is only available if the mtd package is compiled for the
ramips target.

Signed-off-by: David Bauer <mail@david-bauer.net>

1 files changed, 32 insertions, 1 deletions

diff --git a/package/system/mtd/src/mtd.c b/package/system/mtd/src/mtd.c
index fa04c0f95b..eccb4f6a1a 100644
--- a/package/system/mtd/src/mtd.c
+++ b/package/system/mtd/src/mtd.c
@@ -85,6 +85,7 @@ static char *buf = NULL;
 static char *imagefile = NULL;
 static enum mtd_image_format imageformat = MTD_IMAGE_FORMAT_UNKNOWN;
 static char *jffs2file = NULL, *jffs2dir = JFFS2_DEFAULT_DIR;
+static char *tpl_uboot_args_part;
 static int buflen = 0;
 int quiet;
 int no_erase;
@@ -554,6 +555,17 @@ resume:
 		lseek(fd, part_offset, SEEK_SET);
 	}
 
+	/* Write TP-Link recovery flag */
+	if (tpl_uboot_args_part && mtd_tpl_recoverflag_write) {
+		if (quiet < 2)
+			fprintf(stderr, "Writing recovery flag to %s\n", tpl_uboot_args_part);
+		result = mtd_tpl_recoverflag_write(tpl_uboot_args_part, true);
+		if (result < 0) {
+			fprintf(stderr, "Could not write TP-Link recovery flag to %s: %i", mtd, result);
+			exit(1);
+		}
+	}
+
 	indicate_writing(mtd);
 
 	w = e = 0;
@@ -716,6 +728,18 @@ resume:
 #endif
 
 	close(fd);
+
+	/* Clear TP-Link recovery flag */
+	if (tpl_uboot_args_part && mtd_tpl_recoverflag_write) {
+		if (quiet < 2)
+			fprintf(stderr, "Removing recovery flag from %s\n", tpl_uboot_args_part);
+		result = mtd_tpl_recoverflag_write(tpl_uboot_args_part, false);
+		if (result < 0) {
+			fprintf(stderr, "Could not clear TP-Link recovery flag to %s: %i", mtd, result);
+			exit(1);
+		}
+	}
+
 	return 0;
 }
 
@@ -771,6 +795,10 @@ static void usage(void)
 		fprintf(stderr,
 	"        -c datasize             amount of data to be used for checksum calculation (for fixtrx / fixseama / fixwrg / fixwrgg)\n");
 	}
+	if (mtd_tpl_recoverflag_write) {
+		fprintf(stderr,
+	"        -t <partition>          write TP-Link recovery-flag to <partition> (for write)\n");
+	}
 	fprintf(stderr,
 #ifdef FIS_SUPPORT
 	"        -F <part>[:<size>[:<entrypoint>]][,<part>...]\n"
@@ -828,7 +856,7 @@ int main (int argc, char **argv)
 #ifdef FIS_SUPPORT
 			"F:"
 #endif
-			"frnqe:d:s:j:p:o:c:l:")) != -1)
+			"frnqe:d:s:j:p:o:c:t:l:")) != -1)
 		switch (ch) {
 			case 'f':
 				force = 1;
@@ -896,6 +924,9 @@ int main (int argc, char **argv)
 					usage();
 				}
 				break;
+			case 't':
+				tpl_uboot_args_part = optarg;
+				break;
 #ifdef FIS_SUPPORT
 			case 'F':
 				fis_layout = optarg;