The LP SPI driver read and wrote the W0..W15 data buffer registers a
whole 32-bit word at a time, which overran the caller's buffer for
transfers whose length was not a multiple of four bytes and corrupted
the received data. Read and write the data buffer byte-granularly so
sub-word transfers no longer alias adjacent bytes.
The master transfer also programmed the shared bit-length register from
tx_length alone, truncating receive-longer-than-transmit transactions,
and always enabled MOSI even on read-only transfers, clocking out stale
buffer contents. Size each hardware transaction by max(tx_length,
rx_length) and gate MOSI/MISO on the corresponding buffer.
The slave path reused the master's single-shot flow, so it re-triggered
reg_update after preload (clocking out the previous transaction's data)
and offered no way for the caller to publish readiness before the master
started the clock. Split the slave transfer into an arm step that
preloads the buffer and starts the user phase, and a wait step that
blocks on TRANS_DONE and drains only the bytes the master actually
clocked in, tracked in software since reg_usr is not a reliable busy
indicator in slave mode.
Set the LP IO direction for the SPI pads, add
lp_core_lp_spi_bus_deinit() to release the LP GPIO pins, and reset the
LP SPI peripheral at bus initialization so a stale configuration from a
previous run cannot leak into the next.
Use dual-path macros: C keeps fragment-style designated initializers;
C++ uses GNU statement expressions (ESP_LOG_CONFIG_INIT pattern).
Add compile-only C++ regression tests for LP UART/I2C and ULP RISC-V I2C.
Closes https://github.com/espressif/esp-idf/issues/18369
Co-authored-by: Cursor <cursoragent@cursor.com>
lp_core_i2c.h header file has sda and scl pins hardcoded to GPIO6 and
GPIO7 which works only for ESP32C6. ESP32C5 uses GPIO2 and GPIO3 for
I2C SDA and SCL. Hence, added LP_I2C_SCL_IO and LP_I2C_SDA_IO macros
under conditional compilation in library header file, so there is no
need to hardcode I2C GPIO pins and any other test apps or examples
that are including the LP I2C header file can also use Macro directly.
This commit adds a UART driver for the LP core to interact with the LP
UART. The commit also adds an example to demonstrate the usage of the LP
UART driver.
This commit adds support for the LP I2C peripheral driver to be used by
the LP core. An example is also added to demonstrate the usage of the LP
I2C peripheral from the LP core.
