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-rw-r--r--firmware/zpu/lib/spi.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/firmware/zpu/lib/spi.c b/firmware/zpu/lib/spi.c
index 190658d61..6f2f74899 100644
--- a/firmware/zpu/lib/spi.c
+++ b/firmware/zpu/lib/spi.c
@@ -42,11 +42,14 @@ uint32_t spi_transact(bool readback, int slave, uint32_t data, int length, uint3
if ((flags & SPI_LATCH_RISE) != 0) control_word |= (1 << SPI_CORE_DATA_IN_EDGE_SHIFT);
if ((flags & SPI_LATCH_FALL) != 0) control_word |= (0 << SPI_CORE_DATA_IN_EDGE_SHIFT);
+ const uint32_t data_out = data << (32 - length);
+
spi_wait();
spi_core->control = control_word;
- spi_core->data = (data << (32 - length));
+ spi_core->data = data_out;
- if (readback) spi_wait();
+ if (!readback) return 0;
+ spi_wait();
return readback_mux->spi;
}