this is "generic" in that it doesn't require the user to set up anything
specific to go to dormant sleep, unlike the C sdk which requires clock
sources to be configured explicitly and doesn't much care about PLLs. we
will instead take a snapshot of the current clock configuration, switch
to a known clock source (very slow rosc, in this case), go to sleep, and
on wakeup undo everything we've done (ensuring stability of PLLs and
such).
tested locally, but adding tests to HIL seems infeasible. we'd need at
least another pico or extensive modifications to teleprobe since
dormant-sleep breaks SWD (except to rescue-dp), neither of which is
feasible at this point. if we *did* want to add tests we should check
for both rtc wakeups (with an external rtc clock source) and gpio wakeups.
this temporarily takes ownership of pins because we need to clear edge
interrupts before waiting for them (otherwise we may wait indefinitely),
we want to clean up the dormant-wake bits after a wakeup, and doing
anything *else* with the input while we're waiting for a wakeup isn't
possible at all. doing it like this lets us not impose any cost on those
who don't use dormant wakes without entangling dormant waits too badly
with regular interrupt waits.
with uniform treatment of adc inputs it's easy enough to add a new
sampling method. dma sampling only supports one channel at the moment,
though round-robin sampling would be a simple extension (probably a new
trait that's implemented for Channel and &[Channel]). continuous dma as
proposed in #1608 also isn't done here, we'd expect that to be a
compound dma::Channel that internally splits a buffer in half and
dispatches callbacks or something like that.
this lets us treat pins and the temperature sensor uniformly using the
same interface. uniformity in turn lets us add more adc features without
combinatorial explosion of methods and types needed to handle them all.
so far only bank0 interrupts were processed and configured, even if a
qspi pin was given. this is obviously not the right thing to do, so
let's rectify that. the fact that no problems have shown up so far does
suggest that most, if not all, applications don't use this functionality
at all.
this will be mostly not useful to anyone since flash is attached to
qspi, and using flash chips that don't use the *entire* qspi interface
will severly slow down the chip. the code overhead is minimal right now,
but if we also fix interrupt support on qspi pins this will
change (adding more code to potentially hot paths, using more memory for
wakers that are never used, and preventing the qspi gpio irq from being
used in software interrupts as RTIC applications may want to do).
we'll need access to the pin io bank registers for an upcoming fix, and
having both `io` and `io_bank` or similar can get confusing quickly.
rename `io` to `gpio` to avoid this, and also match the type while there.
this removed the RelocatedProgram construction step from pio uses.
there's not all that much to be said for the extra step because the
origin can be set on the input program itself, and the remaining
information exposed by RelocatedProgram can be exposed from
LoadedProgram instead (even though it's already available on the pio_asm
programs, albeit perhaps less convenient). we do lose access to the
relocated instruction iterator, but we also cannot think of anything
this iterator would actually be useful for outside of program loading.
Make sure that the ptr() function for ROM functions always returns
the actual ROM pointer. This allows the use of flash I/O while the
function cache is enabled.
using these will require some linker script intervention. setting the
core0 stack needs linker intervention anyway (to provide _stack_start),
having it also provide _stack_end for the guard to use is not that much
of a stretch.
the region field of the register is four bits wide followed by the valid
bit that causes the rnr update we rely on for the rasr write. 0x08 is
just a bit short to reach the valid bit, and since rp2040 has only 8
regions it (at best) doesn't do anything at all.
the adc constantly pulls a small but significant amount of current while
the hardware is enabled. this can have quite an effect on sleeping
devices that also use the adc.
Change embassy-rp i2c.rs impl of embedded_hal_async::i2c::I2c::transaction
to only do the call to setup() for address once per call to transactions.
Calling setup multiple times results in I2C transactions being skipped
on the bus, even across calls to transaction() or devices.
- don't require an irq binding for blocking-only adc
- abstract adc pins into an AnyPin like interface, erasing the actual
peripheral type at runtime.
- add pull-up/pull-down functions for adc pins
- add a test (mostly a copy of the example, to be honest)
- configure adc pads according to datasheet
- report conversion errors (although they seem exceedingly rare?)
- drop embedded-hal interfaces. embedded-hal channels can do neither
AnyPin nor pullup/pulldown without encoding both into the type
