First, an introduction, i have been lurking around these forums for a while but i didn't had an account, so hello :)
This post is just a part of a personal project im trying to do in converting my kindle into a kind of "cyberdeck". My primary goal is to have plenty of storage in it so i began searching for ways to do it.
I saw posts of people replacing the internal eMMC chip in their kindle, and although it is a great idea, i'm no soldering BGA expert to accomplish that (also, my kindle is a KT4, so i think there's no documented attempt in this model).
Another approach could be finding the solder points of a usb port inside of the kindle (which from what i've seen, happens to be more common on models with a 3G modem variant) which i think the KT4 doesn't have (correct me if they do).
So i began investigating the CPU on my kindle and found out it is an imx6 SoloLite, which has SPI capabilities (the same communication protocol used by SD Cards). I ssh'd into my kindle and found out that there are indeed spi ports "exposed" but the kernel was compiled with only kernel-space use of SPI, in contrast with i2c. So no spidev approach, unless i recompile the kernel with userspace SPI. I could do this and was about to, until i found "mmc_spi.c", a file in the linux kernel source describing a device tree overlay (kind of like a plugin) that itself supports mounting SD cards connected through SPI ports directly into the filesystem, neat right?
More specifically i found this tutorial for the raspberry pi demonstrating how it could be used. Although i was not going to follow this tutorial step-by-step, it served as a guide that i could adapt to the kindle.
I needed a device-tree-compiler, which i already got working by manually installing the respective armel debian package, my next step would be identifying the actual SPI test points in the back of the board.
So here's my question, how would i go in identifying this specific ports?
Thanks! and sorry for the long preamble to the question, wanted to give context.
This post is just a part of a personal project im trying to do in converting my kindle into a kind of "cyberdeck". My primary goal is to have plenty of storage in it so i began searching for ways to do it.
I saw posts of people replacing the internal eMMC chip in their kindle, and although it is a great idea, i'm no soldering BGA expert to accomplish that (also, my kindle is a KT4, so i think there's no documented attempt in this model).
Another approach could be finding the solder points of a usb port inside of the kindle (which from what i've seen, happens to be more common on models with a 3G modem variant) which i think the KT4 doesn't have (correct me if they do).
So i began investigating the CPU on my kindle and found out it is an imx6 SoloLite, which has SPI capabilities (the same communication protocol used by SD Cards). I ssh'd into my kindle and found out that there are indeed spi ports "exposed" but the kernel was compiled with only kernel-space use of SPI, in contrast with i2c. So no spidev approach, unless i recompile the kernel with userspace SPI. I could do this and was about to, until i found "mmc_spi.c", a file in the linux kernel source describing a device tree overlay (kind of like a plugin) that itself supports mounting SD cards connected through SPI ports directly into the filesystem, neat right?
More specifically i found this tutorial for the raspberry pi demonstrating how it could be used. Although i was not going to follow this tutorial step-by-step, it served as a guide that i could adapt to the kindle.
I needed a device-tree-compiler, which i already got working by manually installing the respective armel debian package, my next step would be identifying the actual SPI test points in the back of the board.
So here's my question, how would i go in identifying this specific ports?
Thanks! and sorry for the long preamble to the question, wanted to give context.