For support of SWD we need to be able to clock out special bit
sequences over TMS or SWDIO. Create this as a generic operation,
not yet called by anything, which is split as usual into:
- upper level abstraction ... here, jtag_add_tms_seq();
- midlayer implementation logic hooking that to the lowlevel code;
- lowlevel minidriver operation ... here, interface_add_tms_seq();
- message type for request queue, here JTAG_TMS.
This is done slightly differently than other operations: there's a flag
saying whether the interface driver supports this request. (In fact a
flag *word* so upper layers can learn about other capabilities too ...
for example, supporting SWD operations.)
That approach (flag) lets this method *eventually* be used to eliminate
pathmove() and statemove() support from most adapter drivers, by moving
all that logic into the mid-layer and increasing uniformity between the
various drivers. (Which will in turn reduce subtle bugginess.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
a3245bd7cd