spi: omap2-mcspi: Move bytes per word calculation to the function

Introduce mcspi_bytes_per_word function as replacement for the next code
fragment:

int c = (word_len <= 8)  ? 1 :
	(word_len <= 16) ? 2 :
	/* word_len <= 32 */ 4;

This code used 2 times in current driver code and will be used 2 times in
the next FIFO buffer support patch. Replace it with inline function with clear
name to improve code legibility.

Signed-off-by: Illia Smyrnov <illia.smyrnov@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 13 insertions, 6 deletions

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 000922abcb87..5a93a0df551f 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -186,6 +186,16 @@ static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
         mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
 }
 
+static inline int mcspi_bytes_per_word(int word_len)
+{
+        if (word_len <= 8)
+                return 1;
+        else if (word_len <= 16)
+                return 2;
+        else /* word_len <= 32 */
+                return 4;
+}
+
 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
                 int is_read, int enable)
 {
@@ -432,10 +442,9 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
                         else /* word_len <= 32 */
                                 ((u32 *)xfer->rx_buf)[elements++] = w;
                 } else {
+                        int bytes_per_word = mcspi_bytes_per_word(word_len);
                         dev_err(&spi->dev, "DMA RX penultimate word empty");
-                        count -= (word_len <= 8)  ? 2 :
-                                (word_len <= 16) ? 4 :
-                                /* word_len <= 32 */ 8;
+                        count -= (bytes_per_word << 1);
                         omap2_mcspi_set_enable(spi, 1);
                         return count;
                 }
@@ -453,9 +462,7 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
                         ((u32 *)xfer->rx_buf)[elements] = w;
         } else {
                 dev_err(&spi->dev, "DMA RX last word empty");
-                count -= (word_len <= 8)  ? 1 :
-                         (word_len <= 16) ? 2 :
-                       /* word_len <= 32 */ 4;
+                count -= mcspi_bytes_per_word(word_len);
         }
         omap2_mcspi_set_enable(spi, 1);
         return count;