spi: rspi: Extract rspi_pio_transfer()

The various PIO loops are very similar. Consolidate into a single
function rspi_pio_transfer().

Both buffer pointers can be NULL, as RSPI supports TX-only mode, and
Dual/Quad SPI Transfers are unidirectional.

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

1 files changed, 33 insertions, 62 deletions

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index ece8f6037943..fdbd46d0c570 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -438,15 +438,24 @@ static int rspi_data_in(struct rspi_data *rspi)
         return data;
 }
 
-static int rspi_data_out_in(struct rspi_data *rspi, u8 data)
+static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
+                             unsigned int n)
 {
-        int ret;
-
-        ret = rspi_data_out(rspi, data);
-        if (ret < 0)
-                return ret;
+        while (n-- > 0) {
+                if (tx) {
+                        int ret = rspi_data_out(rspi, *tx++);
+                        if (ret < 0)
+                                return ret;
+                }
+                if (rx) {
+                        int ret = rspi_data_in(rspi);
+                        if (ret < 0)
+                                return ret;
+                        *rx++ = ret;
+                }
+        }
 
-        return rspi_data_in(rspi);
+        return 0;
 }
 
 static void rspi_dma_complete(void *arg)
@@ -644,13 +653,11 @@ static int rspi_is_dma(const struct rspi_data *rspi, struct spi_transfer *t)
 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;
+        int ret;
 
         spcr = rspi_read8(rspi, RSPI_SPCR);
-        if (rx_buf) {
+        if (xfer->rx_buf) {
                 rspi_receive_init(rspi);
                 spcr &= ~SPCR_TXMD;
         } else {
@@ -658,18 +665,9 @@ static int rspi_transfer_out_in(struct rspi_data *rspi,
         }
         rspi_write8(rspi, spcr, RSPI_SPCR);
 
-        while (remain > 0) {
-                ret = rspi_data_out(rspi, *tx_buf++);
-                if (ret < 0)
-                        return ret;
-                if (rx_buf) {
-                        ret = rspi_data_in(rspi);
-                        if (ret < 0)
-                                return ret;
-                        *rx_buf++ = ret;
-                }
-                remain--;
-        }
+        ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
+        if (ret < 0)
+                return ret;
 
         /* Wait for the last transmission */
         rspi_wait_for_tx_empty(rspi);
@@ -694,19 +692,13 @@ static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
 static int rspi_rz_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;
+        int ret;
 
         rspi_rz_receive_init(rspi);
 
-        while (remain > 0) {
-                ret = rspi_data_out_in(rspi, *tx_buf++);
-                if (ret < 0)
-                        return ret;
-                *rx_buf++ = ret;
-                remain--;
-        }
+        ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
+        if (ret < 0)
+                return ret;
 
         /* Wait for the last transmission */
         rspi_wait_for_tx_empty(rspi);
@@ -726,19 +718,13 @@ static int rspi_rz_transfer_one(struct spi_master *master,
 static int qspi_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;
+        int ret;
 
         qspi_receive_init(rspi);
 
-        while (remain > 0) {
-                ret = rspi_data_out_in(rspi, *tx_buf++);
-                if (ret < 0)
-                        return ret;
-                *rx_buf++ = ret;
-                remain--;
-        }
+        ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
+        if (ret < 0)
+                return ret;
 
         /* Wait for the last transmission */
         rspi_wait_for_tx_empty(rspi);
@@ -748,15 +734,11 @@ static int qspi_transfer_out_in(struct rspi_data *rspi,
 
 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
 {
-        const u8 *buf = xfer->tx_buf;
-        unsigned int i;
         int ret;
 
-        for (i = 0; i < xfer->len; i++) {
-                ret = rspi_data_out(rspi, *buf++);
-                if (ret < 0)
-                        return ret;
-        }
+        ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
+        if (ret < 0)
+                return ret;
 
         /* Wait for the last transmission */
         rspi_wait_for_tx_empty(rspi);
@@ -766,18 +748,7 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
 
 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
 {
-        u8 *buf = xfer->rx_buf;
-        unsigned int i;
-        int ret;
-
-        for (i = 0; i < xfer->len; i++) {
-                ret = rspi_data_in(rspi);
-                if (ret < 0)
-                        return ret;
-                *buf++ = ret;
-        }
-
-        return 0;
+        return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
 }
 
 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,