I have a problem that I've been working on for the last couple of days but haven't made any significant progress. I'm hoping that I might find some help here.
So I have a Riotboard, and I have to figure out a way how to get the entire peripheral break-out header working on Android, so I can write some control methods and pass them over to Android developers. I personally think it's a bit weird, that you have a hardware Android board and not ship it out with direct control capabilities, but hey, that's life for you.
Anyways, as you probably know, the main issue with working on Android is the lack of a device tree and I can't afford to wait for one. I've downloaded the last android image source files with the intention of either writing my own character driver or modifying the kernel settings so I'd successfully break out the hardware into user-space and then compiling a complete custom image. This is where I hit a wall. I'm not a Linux developer, but I've been learning intensively and covered a lot of ground in the last couple of days. But when checking over the kernel source files, I've figured out that there are layers and layers of abstractions in the code and I can't wrap my head around them.
I've learned a lot reading through and following this thread:
and I've gotten pretty familiar with the device datasheet -> I have all the relevant register addresses written out, but I'm still having trouble connecting the dots and building a working implementation. Currently, I'm really desperate simply to get the GPIO working, but my final goal is to enable every peripheral on the break-out -> Uart's, SPI, I2C and PWM.
I'm guessing a good place to start would be modifying the u-boot to set the MUX registers on GPIO's to 0x05. Can anyone help me with this and perhaps push me in the right direction?