spi: rspi: Merge rspi_send_pio() and rspi_receive_pio()

rspi_send_pio() and rspi_receive_pio() are very similar:
  - the former only sends data, using TX Only Mode,
  - the latter sends and receives full duplex data to/from the hardware,
    but uses dummy transmit data.
Merge them into rspi_transfer_out_in(), now supporting full duplex if
needed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index d837c502930889e04203cf45025ed6e6f5aae214..cc90136d02c8523418ea7755dc92ce987bf296ef 100644 (file)
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -389,27 +389,6 @@ static int rspi_data_out_in(struct rspi_data *rspi, u8 data)
        return rspi_data_in(rspi);
 }
 
-static int rspi_send_pio(struct rspi_data *rspi, struct spi_transfer *t)
-{
-       int remain = t->len, ret;
-       const u8 *data = t->tx_buf;
-
-       while (remain > 0) {
-               rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
-                           RSPI_SPCR);
-
-               ret = rspi_data_out(rspi, *data++);
-               if (ret < 0)
-                       return ret;
-               remain--;
-       }
-
-       /* Waiting for the last transmission */
-       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
-
-       return 0;
-}
-
 static int qspi_send_pio(struct rspi_data *rspi, struct spi_transfer *t)
 {
        int remain = t->len, ret;
@@ -563,28 +542,6 @@ static void rspi_receive_init(const struct rspi_data *rspi)
                            RSPI_SPSR);
 }
 
-static int rspi_receive_pio(struct rspi_data *rspi, struct spi_transfer *t)
-{
-       int remain = t->len, ret;
-       u8 *data = t->rx_buf;
-
-       rspi_receive_init(rspi);
-
-       while (remain > 0) {
-               rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
-                           RSPI_SPCR);
-
-               /* dummy write data for generate clock */
-               ret = rspi_data_out_in(rspi, DUMMY_DATA);
-               if (ret < 0)
-                       return ret;
-               *data++ = ret;
-               remain--;
-       }
-
-       return 0;
-}
-
 static void qspi_receive_init(const struct rspi_data *rspi)
 {
        u8 spsr;
@@ -729,27 +686,61 @@ static int rspi_is_dma(const struct rspi_data *rspi, struct spi_transfer *t)
        return 0;
 }
 
+static int rspi_transfer_out_in(struct rspi_data *rspi,
+                               struct spi_transfer *xfer)
+{
+       int remain = xfer->len, ret;
+       const u8 *tx_buf = xfer->tx_buf;
+       u8 *rx_buf = xfer->rx_buf;
+       u8 spcr, data;
+
+       rspi_receive_init(rspi);
+
+       spcr = rspi_read8(rspi, RSPI_SPCR);
+       if (rx_buf)
+               spcr &= ~SPCR_TXMD;
+       else
+               spcr |= SPCR_TXMD;
+       rspi_write8(rspi, spcr, RSPI_SPCR);
+
+       while (remain > 0) {
+               data = tx_buf ? *tx_buf++ : DUMMY_DATA;
+               ret = rspi_data_out(rspi, data);
+               if (ret < 0)
+                       return ret;
+               if (rx_buf) {
+                       ret = rspi_data_in(rspi);
+                       if (ret < 0)
+                               return ret;
+                       *rx_buf++ = ret;
+               }
+               remain--;
+       }
+
+       /* Wait for the last transmission */
+       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
+
+       return 0;
+}
+
 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
                             struct spi_transfer *xfer)
 {
        struct rspi_data *rspi = spi_master_get_devdata(master);
-       int ret = 0;
+       int ret;
+
+       if (!rspi_is_dma(rspi, xfer))
+               return rspi_transfer_out_in(rspi, xfer);
 
        if (xfer->tx_buf) {
-               if (rspi_is_dma(rspi, xfer))
-                       ret = rspi_send_dma(rspi, xfer);
-               else
-                       ret = rspi_send_pio(rspi, xfer);
+               ret = rspi_send_dma(rspi, xfer);
                if (ret < 0)
                        return ret;
        }
-       if (xfer->rx_buf) {
-               if (rspi_is_dma(rspi, xfer))
-                       ret = rspi_receive_dma(rspi, xfer);
-               else
-                       ret = rspi_receive_pio(rspi, xfer);
-       }
-       return ret;
+       if (xfer->rx_buf)
+               return rspi_receive_dma(rspi, xfer);
+
+       return 0;
 }
 
 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,