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Research on Fully-Free phone
Added by Trevor Best almost 10 years ago
Hi All,
I've been doing research into the viability of manufacturing a fully free phone, and I was wondering where I would find information on parts. Is there some central resource for cell phone parts? Also how do I tell if they are fully free once I find them? Please forgive my naivete :)
Replies (5)
RE: Research on Fully-Free phone - Added by Paul Kocialkowski almost 10 years ago
- Make sure the full Linux kernel source can be released
- Pick a platform where all the bootloaders are free software (e.g. iMX, OMAP, Allwinner)
- Disable any signature check on the bootloaders and kernel
- Make UART pins available for easier debugging and flashing when
working on e.g. a free software bootloader - Make sure the modem is not part of the SoC and cannot access the
phone's memory, RAM, GPS and cannot control the audio chip. - Make sure it is easy to reflash the phone with free software tools
- Make sure the chips use standard protocols (Modem would use AT, GPS
would use NMEA, etc) - Make sure the kernel interfaces are standard Linux interfaces (ALSA,
V4L2, etc) - Use the ath9k_htc WiFi chipset, which can be embedded in a phone and
has a free firmware - Use a platform with a Mali or Adreno GPU, for which we are likely to
see a working free software implementation in the near future
In order to reliable achieve privacy, a way to disconnect the modem from its antenna is the way to go.
RE: Research on Fully-Free phone - Added by Scott Heppler almost 10 years ago
"Use a platform with a Mali or Adreno GPU, for which we are likely to
see a working free software implementation in the near future"
RE: Research on Fully-Free phone - Added by G S over 9 years ago
Paul Kocialkowski wrote:
In order to reliable achieve privacy, a way to disconnect the modem from its antenna is the way to go.
Hello. I tried the antenna disconnection on some cheap android phone and the result is rather discouraging:
even with antenna disconnected the phone was still able to pick up the wifi signal from nearby wifi routers, just with way poorer strength. I had no sim card to test the signal for GSM channel but being in city with lots of cellular towers I think there is a risk that with GSM signal being strong from the outside - the disconnection of external antenna does not make much difference.
So - anyone having any experience with disabling GSM modem really properly? I just something for pocket note taking without any wifi/call functionality. So I carry it with me, take notes and export them through usb wire. There are lots of cheap Android phones to be potentially converted to such 'PDA' format - but it seems there is no reliable way to fully disable all wireless even if one is ready to cut mainboard wires and solder/un-solder stuff?
Any comments?
RE: Research on Fully-Free phone - Added by Glenn McGrath over 9 years ago
To "disable" an antenna you could connect it to an earth (or 0v) or transmit noise into it to corrupt what it is receiving.
There is also a thing called a faraday cage, which doesnt sound very practical, but i think its the concept used behind the RFID blocking sleeves used to prevent the theft of credit cards details.
RE: Research on Fully-Free phone - Added by Paul Kocialkowski over 9 years ago
I had no sim card to test the signal for GSM channel but being in city with lots of cellular towers I think there is a risk that with GSM signal being strong from the outside - the disconnection of external antenna does not make much difference.
It would be worth trying with GSM as well, I am uncertain about whether it can still substantially use the GSM network to e.g. transmit data.
So - anyone having any experience with disabling GSM modem really properly? I just something for pocket note taking without any wifi/call functionality. So I carry it with me, take notes and export them through usb wire. There are lots of cheap Android phones to be potentially converted to such 'PDA' format - but it seems there is no reliable way to fully disable all wireless even if one is ready to cut mainboard wires and solder/un-solder stuff?
Well, you could probably just keep it powered off/not booted. I will soon (months) add instructions on how to do that for each device.