spi/xilinx: Leave the IRQ always enabled.

Instead of enabling the IRQ and disabling it for every transaction.

Specially the small transactions (1,2 words) benefit from removing 3 bus
accesses.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index 1890af8f8636c723d8f69429a6426d65fdff1116..d933207c212ce96753b3c4ca5dcb09ecf8cff89b 100644 (file)
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -167,8 +167,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi)
        /* Reset the SPI device */
        xspi->write_fn(XIPIF_V123B_RESET_MASK,
                regs_base + XIPIF_V123B_RESETR_OFFSET);
-       /* Disable all the interrupts just in case */
-       xspi->write_fn(0, regs_base + XIPIF_V123B_IIER_OFFSET);
+       /* Enable the transmit empty interrupt, which we use to determine
+        * progress on the transmission.
+        */
+       xspi->write_fn(XSPI_INTR_TX_EMPTY,
+                       regs_base + XIPIF_V123B_IIER_OFFSET);
        /* Enable the global IPIF interrupt */
        xspi->write_fn(XIPIF_V123B_GINTR_ENABLE,
                regs_base + XIPIF_V123B_DGIER_OFFSET);
@@ -237,7 +240,6 @@ static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi, int n_words)
 static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
 {
        struct xilinx_spi *xspi = spi_master_get_devdata(spi->master);
-       u32 ipif_ier;
 
        /* We get here with transmitter inhibited */
 
@@ -246,14 +248,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
        xspi->remaining_bytes = t->len;
        reinit_completion(&xspi->done);
 
-
-       /* Enable the transmit empty interrupt, which we use to determine
-        * progress on the transmission.
-        */
-       ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET);
-       xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY,
-               xspi->regs + XIPIF_V123B_IIER_OFFSET);
-
        for (;;) {
                u16 cr;
                int n_words;
@@ -290,9 +284,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
                        break;
        }
 
-       /* Disable the transmit empty interrupt */
-       xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET);
-
        return t->len - xspi->remaining_bytes;
 }