Android – Page 5 – Roo's View

Restore Rogers Galaxy Tab 7 to stock

When I got my Galaxy Tab 7″ one of the first things I did was to see if I could collect the stock firmware in a format that was useful in case I ever wanted to restore the tablet back to it’s stock form. It turned out that the 2.2 based firmware was not easily available on the net, and neither was the 2.3 version.

The results of my work are captured in an XDA thread, but restoring from those captures was an exercise left to the reader. The 2.2 (froyo) image is captured directly from the device, I first rooted the tablet with SuperOneClick then used rotobackup to capture a heimdall friendly set of files for flashing. The original work was tracked in another XDA thread where you can read the blow by blow if you’re interested. For 2.3 (gingerbread) I was able to grab the intermediate files from Kies during the normal upgrade process – the rest of this post will talk about how to use those files to restore the P1000R to a stock 2.3 state.

I’m using heimdall version 1.3.1 on Linux, but other versions and platforms should work fine. I particularly like using Linux to flash the GalaxyTab as it doesn’t suffer the same driver madness that Windows seems to have, USB devices just work. I’ll assume you can find the download and extract the files.

You’ll want to specify the PIT file – gt-p1000_mr.pit, it’s safe to select the repartition box as we’ll be doing the full monty here [sharp eyed readers will notice that the picture at the top of this post doesn’t have the box checked, that’s a mistake on my part – go ahead and check it]. The files map to the heimdall partition names as follows:

MODEM -> modem.bin CACHE -> cache.rfs KERNEL -> zImage FACTORYFS -> factoryfs.rfs PARAM -> param.lfs IBL+PBL -> boot.bin SBL -> sbl.bin

So click on the Add button and specify the partition type and files from the downloaded and extracted ROM.

Next you need to get your device into download mode. My preferred approach is to hold the power+volume down buttons until the download screen appears (yellow triangle with android digging). Now you can click start on heimdall.

Under Linux at least , this will hit 100% and then fail to reboot. That’s ok. Wait a minute or two to make sure it’s really done, then force it to reboot into recovery mode by holding power+volume up until you see the recovery screen.

Assuming the flash has gone well, the stock recovery will start up and automatically try to install some updates. You should see:

-- Updating filesystem... E:failed to mount /dbdata (Invalid argument) E:discard_filesystem_for_rfs:Can't mount /dbdata

-- Wiping cache... Formatting /cache Cache wipe failed.

Don’t panic. Remember that this update was expecting to have come from a properly installed 2.2 stock, we’re leaping into the middle of the process.

Using the recovery menus, select ‘factory reset + wipe data’ followed by ‘wipe cache’. One hint for those not used to the stock recovery image, the capacitive home button is used to select entries and volume up/down for navigation.

Now you can reboot. The first boot will take a while as it sorts things out and rebuilds the cache(s). All should go well and you’ll be greeted by the stock home screen.

i9000 ICS – CyanogenMod 9 Alpha

One of the things that I look for in a phone is community support. For me there are two main reasons this is important: 1) It’s nice to have a large group of people you can ask questions of, or an active forum you can search for answers on 2) When later versions of Android are released, that community will hopefully build a version for your phone.

If you’ve been watching the tech news, there have been rumors that Samsung will support Ice Cream Sandwich (ICS) on the Samsung Galaxy S (SGS) and claims that it won’t. The latest news appears to be that they will not upgrade the device, a bit sad as it was only released 18 months ago. So not even kept current through the length of most cell company contracts. This is one area where the iPhone has done right for the consumer.

If you’re interested in getting ICS for your i9000 (or in my case the i9000m) skip over to the XDA Forum and read through the huge thread. The team behind it are the same folk who helped bring CyanogenMod to the SGS originally and are now working on CM9. This is an alpha, there will be rough edges and I don’t suggest people leap in unless they are very brave.

I originally tried Build 11 and that didn’t work well enough for me to switch from the 7.1 stable I was on but it was close. Build 12 appears to be quite good, with a few changes I needed to make for my usage, specifically adding dropbear (SSHD) and rsync so I can do nightly backups (which I’ll talk about at the end of this post).

The forum thread has these instructions for people coming from CM7

Upgrading from CM7?

Do a Nandroid Backup!

WIPE (wipe data/factory reset + wipe cache partition)

Install the ROM from internal sdcard using ClockworkMod (CWM) Recovery

Optionally install the Google Addon

I would recommend that you consider getting CM7 first, it’s a good base to work from and there will be better how to and help to get it working. Experience there will translate over to working with the ICS Alpha.

Here are my steps I used when moving to ICS .

Do some backups of your application data
Backup SMS using SMS Backup+
Backup Plume settings (and any other apps that support backup)
Take some screenshots of your home screens, nice reference to what you have. Also consider grabbing a list of the apps you have installed
Reboot into recovery – perform a backup in CWM
“backup and restore -> Backup”
Mount USB mode in CWM
” mounts and storage -> mount USB storage”
Copy backup to PC (just in case something really bad happens)
Copy new ICS Alpha files to phone
teamhacksung_galaxysmtd-ota-eng.BUILD12.zip
gappsv7.1.zip
Now wipe from CWM
“wipe data/factory reset”
“wipe cache partition”
Install the two .zip files we copied above, build12 first.
At this point my heart always stops, as during the install of the firmware, the phone will reboot suddenly. Do. Not. Panic.
It will automatically boot into ICS after the install. Now optionally reboot into recovery to install gapps.

There is a list of known issues in the main thread, you can post bug reports there but please search the thread so you don’t ask something obvious. There is another thread for discussion (ie: anything that is not a bug report).

Each time I’ve done this type of upgrade I seem to get burned by the Android Market treating the new ROM as if it were a new device, thus it doesn’t restore any of my apps. Good thing I had taken a backup of the list above. Having done this a few times, using a desktop web browser to the Market and installing from there to my phone is much faster.

My experience so far

The good stuff:

ICS is very, very pretty
Recent applications with preview is cool
Quick access to camera on lock screen is nice
Web browser handling of multiple windows more like iOS Safari
Calendar is a big improvement, phone interface much nicer too
It has USB mode instead of MTP

Why it’s still an alpha

I was unlucky and had a sync problem with the calendar
This is a known problem with a solution – flash the gapps_fixer.zip
Every once in a while the lock screen has no touch response, lock/unlock again with power button fixes
I had mapped long press menu to search, that CM feature isn’t supported (yet?)
I miss “quiet times” from CM – using Sound Manager v2 to get same function
Power-off sound comes a while after screen is dark – I disabled the sound to resolve

So far no major issues. Only 1 of the ~50 apps I use indicated it wasn’t compatible – and I’m sure that’s just how they’ve tagged it in the market. The battery life appears to be about the same as CM 7.1.

One observation was my modem didn’t change from KG3 unlike my experience flashing CM7 where the modem did change, it seems my understanding of how the modem is updated (or not) is flawed.

I also briefly tried out a pure AOSP from Onecosmic and while it seems a bit more mature than the CM9 Alpha, it didn’t fit what I wanted (personal taste).

Getting SSHD and rsync working

I had previously written about getting SSHD working on CM7.1 and that I used rsnapshot to do incremental nightly backups of my phone. This has saved me at least once when my phone got very sick and needed to be wipe and freshly installed, having a day old backup was nice. Also when going from version to version I’m able to grab configuration details like the dropbear configuration – this allows me to reuse the same keyed ssh login without having to repeat the entire setup.

The ICS Alpha was missing dropbear. It turns out that the version from CM7.1 can be used – I specifically picked the ones from nightly build 181.

First you need to remount the /system filesystem to be read-write.

mount -o remount,rw /dev/block/mtdblock2 /system

Grab dropbear, dropbearkey and rsync and put them in /system/xbin. Make sure to use chmod 755 on them to make them executable. Probably a good idea to reboot after this.

As I’m going to re-use my configuration files from my backup, I don’t need to use the setup steps from my blog post – I just use the abbreviated version below, but if you’re doing this clean follow the original write up.

# mkdir /data/dropbear # mkdir /data/dropbear/.ssh

Copy the following files from backup to the phone

/data/dropbear/.ssh /data/dropbear/.ssh/authorized_keys /data/dropbear/dropbear_rsa_host_key /data/dropbear/dropbear_dss_host_key

Then just fix the permissions

# chmod 755 /data/dropbear /data/dropbear/.ssh # chmod 644 /data/dropbear/dropbear*host_key # chmod 600 /data/dropbear/.ssh/authorized_keys

The ICS Alpha is also missing the ability to set the hostname, you can hack around it by using the following command.

# setprop net.hostname yourhostname

And of course, we need to launch dropbear

# dropbear -s -g

I still need to figure out how to get these into a script that will run on reboot, for now I’m just doing the last two command manually after every reboot.

Unlocking Samsung Galaxy S Vibrant (Bell)

I’ve been a big fan of unlocked GSM phones since my first one back in 2009. I’ve also been through a surprising number of different phone since then, but all of them have been 2nd (or 3rd) hand and have been a good price for a phone that still has lots of use left in it. My latest phone the Samsung Galaxy S Vibrant (i9000m) is no different, but it came to me locked to Bell.

I purchased the i9000m knowing it could be easily unlocked if you had the right magic. With the stock firmware, if you don’t have the phone unlocked you’ll see what’s pictured at the top of this post when you install a SIM card.

It turns out the forums have a great how to guide, with pointers to an app on the Android Market if you’re afraid of a little bit of hex editing. It should go without saying that I selected the hex editing route. I’ll describe the steps I used here, but all credit to the folks in the forums for figuring this out.

I will assume that you’ve rooted your i9000m and you’re not incapable of using a hex editor.

Step 1: We’re going to copy some non-volatile memory off the phone that contains the ‘lock’. Perform the following commands on the phone (probably via ADB).

$ su # cat /efs/nv_data.bin >> /sdcard/nv_data.bin

Now copy that file onto your PC for editing. Make a backup of the original before step 2.

Step 2: Edit that file, I used hexedit on Ubuntu. The lock bit is inside of the byte at 0x181469 in the file. See the green circle below, change that 01 into a 00 and save the file.

Starting at offset 0x181468 you should see the series of digits: ff 01 00 00 00 00 46 46

The XDA post describes it as follows:

There are 5 different types of locks in 5 different bytes

the FF byte should be left alone
the first byte after the FF is the network lock
the next byte is the network subset lock
the next byte is the sp lock
the next byte is the cp lock
the last byte appears to be a data lock.
the 46 46 should be left alone

Step 3: Use the modified file to update your phone. Let’s assume you copied the modified file to /sdcard/nv_data.bin on the phone, and again the commands below are executed on the phone.

$ su # rm /efs/nv_data.bin # rm /efs/nv_data.bin.md5 # cat /sdcard/nv_data.bin >> /efs/nv_data.bin # chmod 755 /efs/nv_data.bin # chown radio.radio /efs/nv_data.bin || chown 1001.1001 /efs/nv_data.bin # reboot

That’s it, you’re unlocked. The unlock should persist across ROM (firmware) changes.

References: a great article with pointers to valuable information on the i9000 series.