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path: root/drivers/spi/spi-xilinx.c
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Diffstat (limited to 'drivers/spi/spi-xilinx.c')
-rw-r--r--drivers/spi/spi-xilinx.c74
1 files changed, 35 insertions, 39 deletions
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index e1d769607425..34d18dcfa0db 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -267,7 +267,6 @@ 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;
- u16 cr;
/* We get here with transmitter inhibited */
@@ -276,7 +275,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
xspi->remaining_bytes = t->len;
INIT_COMPLETION(xspi->done);
- xilinx_spi_fill_tx_fifo(xspi);
/* Enable the transmit empty interrupt, which we use to determine
* progress on the transmission.
@@ -285,12 +283,41 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY,
xspi->regs + XIPIF_V123B_IIER_OFFSET);
- /* Start the transfer by not inhibiting the transmitter any longer */
- cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) &
- ~XSPI_CR_TRANS_INHIBIT;
- xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET);
+ for (;;) {
+ u16 cr;
+ u8 sr;
+
+ xilinx_spi_fill_tx_fifo(xspi);
+
+ /* Start the transfer by not inhibiting the transmitter any
+ * longer
+ */
+ cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) &
+ ~XSPI_CR_TRANS_INHIBIT;
+ xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET);
+
+ wait_for_completion(&xspi->done);
+
+ /* A transmit has just completed. Process received data and
+ * check for more data to transmit. Always inhibit the
+ * transmitter while the Isr refills the transmit register/FIFO,
+ * or make sure it is stopped if we're done.
+ */
+ cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET);
+ xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT,
+ xspi->regs + XSPI_CR_OFFSET);
+
+ /* Read out all the data from the Rx FIFO */
+ sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET);
+ while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) {
+ xspi->rx_fn(xspi);
+ sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET);
+ }
- wait_for_completion(&xspi->done);
+ /* See if there is more data to send */
+ if (!xspi->remaining_bytes > 0)
+ break;
+ }
/* Disable the transmit empty interrupt */
xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET);
@@ -314,38 +341,7 @@ static irqreturn_t xilinx_spi_irq(int irq, void *dev_id)
xspi->write_fn(ipif_isr, xspi->regs + XIPIF_V123B_IISR_OFFSET);
if (ipif_isr & XSPI_INTR_TX_EMPTY) { /* Transmission completed */
- u16 cr;
- u8 sr;
-
- /* A transmit has just completed. Process received data and
- * check for more data to transmit. Always inhibit the
- * transmitter while the Isr refills the transmit register/FIFO,
- * or make sure it is stopped if we're done.
- */
- cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET);
- xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT,
- xspi->regs + XSPI_CR_OFFSET);
-
- /* Read out all the data from the Rx FIFO */
- sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET);
- while ((sr & XSPI_SR_RX_EMPTY_MASK) == 0) {
- xspi->rx_fn(xspi);
- sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET);
- }
-
- /* See if there is more data to send */
- if (xspi->remaining_bytes > 0) {
- xilinx_spi_fill_tx_fifo(xspi);
- /* Start the transfer by not inhibiting the
- * transmitter any longer
- */
- xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET);
- } else {
- /* No more data to send.
- * Indicate the transfer is completed.
- */
- complete(&xspi->done);
- }
+ complete(&xspi->done);
}
return IRQ_HANDLED;