Let’s take a look at the steps required to manually install a firmware update to the Wink Hub.
The update works by booting into a separate linux image located on different flash partitions so that it can then download new images and flash them to the main application partitions.
So to update manually we are going to do the same thing, but first we need to root the updater before we boot into it.
Let’s mount the rootfs of the updater to /tmp/updater:
ubiattach -p /dev/mtd2
mount -t ubifs ubi2:rootfs /tmp/updater
We need to remove the root password on this image like before, copy over our ssh key, and remove the S99local script that runs the update process from /etc/init.d. Also make sure we have our wifi configuration saved properly to the database (see original root post). We may also want to save copies of other files we have modified such as from /var/www. For insurance let’s also unlock the bootloader:
fw_setenv bootdelay 5
The bootloader parameters are sometimes restored to defaults so we should also edit /database_default/u-boot.env here and each time we update the app-rootfs.
Once we are ready to boot over we can do:
echo "1" > /database/DO_UPDATE
Then we are ready to reboot.
Once we are booted into the updater image we can follow the example of the /root/platform/upgrade.sh script to manually download and flash the updates. So far only the application rootfs has been updated and can be downloaded from:
At this time the update is small enough that we can download it to /tmp and flash it using:
ubiformat /dev/mtd5 -f /tmp/app-rootfs.ubi
After they are in place, we will need to root again using the same process outlined above (except we are working with /dev/mtd5 now). Also pay attention to any changes that may be present in the update such as disabling the UART login (/etc/inittab), not starting dropbear, etc… And we should modify the S31platform script and block the cloud addresses again as we did in the original root post.
Once we are ready to boot back into the application we can do:
echo "0" > /database/DO_UPDATE
And reboot, fingers crossed.
PS – Let’s say we want to take a look at the rootfs before we update. To do so on a linux desktop, we can download the ubi image and:
modprobe nandsim first_id_byte=0x01 second_id_byte=0xf1 third_id_byte=0x00 fourth_id_byte=0x1d
dd if=app-rootfs.ubi of=/dev/mtdblock0 bs=2048
ubiattach /dev/ubi_ctrl -m 0 -O 2048
mount -t ubifs ubi0_0 /media/ubifs
The above assumes you have no other mtdblock devices on your system. It also simulates the actual flash chip used in the device which is larger than necessary for just playing with the rootfs.