Adds a new spi_transcieve_cb API which enables asynchronous
SPI transactions with callback notification.
The exist spi_transcieve_async API remains and uses the new
spi_transcieve_cb API to provide a k_poll_signal notifier.
The driver API changes to provide a callback and userdata
parameter to async transcieve. All drivers in the tree
have been updated to the change.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
Implement support for half duplex communication in the bit bang SPI
driver. The SPI driver will use the MOSI pin is for both TX and RX
operations when using half duplex mode.
In half-duplex mode, the driver configures the MOSI pin as an input
pin for input only transactions. Transactions that are bidirectional
are forbidden. After an SPI transaction, the MOSI pin is left as an
input if it was an RX transaction or an output after a TX
transaction. Like before, the MOSI pin is initialized as an
(inactive) output pin when the bus is initialized.
Signed-off-by: Andreas Sandberg <andreas@sandberg.uk>
spi_context_cs_configure_all() is currently called from
spi_bitbang_transceive(). This causes a glitch when combined with
SPI_HOLD_ON_CS is used.
Move the initialization to spi_bitbang_init which is what the other
SPI drivers seem to do.
Signed-off-by: Andreas Sandberg <andreas@sandberg.uk>
The SPI bitbang driver doesn't correctly initialize the list of CS
GPIOs. As a consequence, SPI buses using the bitbang driver won't
drive CS low. Add the missing initialization.
Signed-off-by: Andreas Sandberg <andreas@sandberg.uk>
In order to bring consistency in-tree, migrate all drivers to the new
prefix <zephyr/...>. Note that the conversion has been scripted, refer
to #45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
This adds an spi master mode driver via bitbanged gpio. Only syncronous
transfers are implemented. Clock signal timing is accomplished via busy
waits, the gpios are manipulated via the standard gpio interface; these
two factors limit the frequency at which it can operate - but here
a simple and generic implementation was chosen over performance.
The driver supports the various clock polarity and phase
configurations, and can also work with word sizes which are non
multiples of 8bits, currently up to 16 bits.
A sample program is also added demonstrating basic use of the driver
with 9bit data words.
Signed-off-by: Marc Reilly <marc@cpdesign.com.au>
