This commit refactors USB string code, making it, hopefully, less
buggy and more easier to understand. It also removes "magic" bit
manipulation and "magic" numbers;
This commits adds a new error code that can be return from a
registered control callback: USBD_REQ_NEXT_CALLBACK. This return code
signifies that the callback is done processing the data successfully,
but user would like to have all matching callbacks down the callback
chain to be executed too.
This change allows for example to intercept standard requests like
GET_DESCRIPTOR, do some small action upon receiving of one, but still
have the standard callback executed and do it's job. This way user
doesn't have to re-implement standard GET_DESCRIPTOR functionality if
they want to intercept that request to do some small thing.
This commit add an extra field to the _usbd_device, that allows to
keep track of the number of USB strings which allows simplify
boundaries checking code in usb_standard_get_descriptor.
This commit also changes the index base for strings in
usb_standard_get_descriptor which allows to get rid of necessity to
have a dummy one-character string in a strings array.
this adds support for energy micro's efm32 tiny gecko, gecko, leopard gecko and
giant gecko series.
also, the experimental libopencmsis is included in this branch, as it is
required for full operation of the free energymicro standard library
this merges common c and header files of different architectures, adds a
dispatch mechanism and yaml descriptions of interrupt handlers from which the
whole interrupt table setup c code is generated.
the LM3S irq list was previously unused as it was missing in the
dispatch files; now it got added. (before HEAD^, it wouldn't have made
any difference because the discriminating constant wasn't defined
anyway)
also, this enhances the warning messages
the only change this results in in the example binaries is in the
hackrf-jellybean/systick example, where the the check in
systick_set_clocksource for overflowing from the stm32 area gets used.
these register definitions are common to all cortex mcus. some of the
registers might not be implemented everywhere (especially the floating
point registers), but defining them does no harm.
this modification does not result in any changes in the example
binaries.
