The ADC has a 12bit resolution and its raw output can be read via sysctl(8)
interface.
The driver allows the setup of ADC clock, samples average and open delay
(the number of clock cycles to wait before start the conversion).
The TSC_ADC module is set in the general purpose mode (no touchscreen
support).
Tested on Beaglebone-black.
Written based on AM335x TRM.
Reviewed by: rpaulo
Approved by: adrian (mentor)
Tested by: me, Brian J. McGovern, Sulev-Madis Silber (ketas)
and the functionality it provided into arm/exception.S. Rename the main
irq handling routine from arm_handler_execute() to arm_irq_handler() to
make it more congruent with how other exception handlers are named, and
also update its signature to reflect what has long been reality: it is
passed just a trapframe pointer, no interrupt number argument.
appropriate for each of the 'foo' in the tree. This will allow us to
compile them together (although symbol conflicts prevent us from doing
that today, this just fixes the file name collision).
The TI uart hardware is ns16550-compatible, except that before it can
be used the clocks and power have to be enabled and a non-standard
mode control register has to be set to put the device in uart mode
(as opposed to irDa or other serial protocols). This adds the extra
code in an extension to the standard ns8250 probe routine, and the
rest of the driver is just the standard ns8250 code.
