lpm_enter() must not enter PM1+ if the UART TX FIFO is not empty. Otherwise, the
UART clock gets disabled, and its TX is broken.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Some peripherals have their clocks automatically gated in PM1+ modes, so they
cannot operate. This new mechanism gives peripherals a way to prohibit PM1+
modes so that they can properly complete their current operations before
entering PM1+.
This mechanism is implemented with peripheral functions registered to the LPM
module. These functions return whether the associated peripheral permits or not
PM1+ modes. They are called by the LPM module each time PM1+ might be possible.
If any of the peripherals wants to block PM1+, then the system is only dropped
to PM0.
Partly from: George Oikonomou
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
This uses the core/dev/spi.h header and implements the spi_init()
function and the various macros for SPI operation. ssi.h contains all of
the register locations and information.
This implementation is not very versatile, mostly because I don't how to
make it flexible in the contiki system. It supports pin muxing for the
four spi pins, but other than that picks sensible defaults.
The SPI macros (like SPI_READ()) are defined in
cpu/cc2538/spi-arch.h. In order to use the SPI driver, add the following
includes to your project:
#include "spi-arch.h
#include "dev/spi.h"
Historically $(OBJECTDIR) was created when Makefile.include is read. A
consequence is that combining "clean" with "all" (or any other build
target) results in an error because the clean removes the object
directory that is required to exist when building dependencies.
Creating $(OBJECTDIR) on-demand ensures it is present when needed.
Removed creation of $(OBJECTDIR) on initial read, and added an order-only
dependency forcing its creation all Makefile* rules where the target is
explicitly or implicitly in $(OBJECTDIR).
- For the CC2538, simplify handling of USB_CDC_ACM_LINE_STATE
events. Ignore the Carrier Control (RTS) bit when receiving
a SET_CONTROL_LINE _STATE request, we are a full duplex device.
- Improve behaviour of the CC2531 USB stick when there is no
process on the host to read IN data. Basically, we adopt the
CC2538 approach and we only send data when a DTE is present
