Add a new getrecvbuf callback to the SPI slave device operations
that allows the slave device to provide a pre-allocated receive
buffer directly to the controller. This enables zero-copy data
transfer by allowing the controller to receive data directly into
the device's buffer instead of copying.
Changes:
- Add SPIS_DEV_GETRECVBUF macro and getrecvbuf callback to
spi_slave_devops_s structure in include/nuttx/spi/slave.h
- Implement getrecvbuf in rpmsg_port_spi_slave driver
- Update getdata to return 0 as it's no longer used for this path
Signed-off-by: liaoao <liaoao@xiaomi.com>
liaoao
ae6ad9c193