spi: spi-axi-engine: fix write buffer value to register

This patch fixes buffer value writes in register. The register width is equal with the word length. The value written must be the same size so we must shift 8 bit values and create a value equal to the word length. Signed-off-by: Mircea Caprioru <[email protected]>
analogdevicesinc · Jan 23, 2019 · 42d22f4 · 42d22f4
1 parent 8905c17
commit 42d22f4
Showing 1 changed file with 8 additions and 3 deletions.
diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
@@ -455,11 +455,16 @@ static void spi_engine_write_buff(struct spi_engine *spi_engine,
 				   const uint8_t *buf)
 {
 	void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_SDO_DATA_FIFO;
-	uint8_t len, i;
+	uint8_t len, i, word_len;
+	uint32_t val = 0;
+
+	word_len = spi_engine->word_length;
+	len = DIV_ROUND_DOWN_ULL(word_len, 8);
 
-	len = DIV_ROUND_UP(spi_engine->word_length, 8);
 	for (i = 0; i < len; i++)
-		writel_relaxed(buf[i], addr);
+		val |= buf[i] << (word_len - 8 * (i + 1));
+
+	writel_relaxed(val, addr);
 }
 
 static bool spi_engine_write_tx_fifo(struct spi_engine *spi_engine)