Building a software serial driver

[Torrie Fischer]

Hi, Pranay.

Thanks for having a look.

On Tuesday, June 24, 2014 13:42:35 Pranay Srivastava wrote:
> 
> I looked at uart_register code, it seems there's no read callback so
> that's why you are getting that -EIO.

From what I understand, I'm supposed to set up the interrupts needed in the 
startup function which is called when the device is opened. This never happens 
though, as adding a printk results in no output.

> I think you can put this call in your start_tx since uart_start is
> calling port->start_tx at the end so i guess you should be good there.

I suspect that start_tx is not getting called since adding a printk in my 
start_tx function doesn't result in any output.

> 
> I don't have much idea how will you read from it though.

I'm able to read from it by waiting for a rising edge interrupt and then bit-
banging the GPIO line in userspace, though at a slow baud that is unusable. I 
need 9600 to read from my device :)
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