It is incorrect to call spi_context_release() on a
spi_dw_data object's ctx field before data->ctx->config is first
set in spi_dw_configure(). This is because spi_context_release()
reads ctx->config->operation. In particular, during spi_dw_init(),
calling spi_context_release() reads the uninitialized memory in
spi->ctx->config->operation.
Call spi_context_unlock_unconditionally() instead to properly increase
the semaphore count.
Without this patch, the first call to spi_transceive() can block
forever depending on the value of the uninitialized memory holding
spi->ctx->config->operation.
Signed-off-by: Marti Bolivar <marti.bolivar@linaro.org>
3ac9ca0859