spi: at91-usart: Remove some dead code

dma_request_chan() does not return NULL. It returns a valid pointer or an
error pointer.

So, some dead code can be removed.

The IS_ERR_OR_NULL() in the error handling path are still needed, because
the error handling path is common to the whole function and the
ctlr->dma_xx are NULL when at91_usart_spi_configure_dma() is called.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/84eb08daf85d203b34af9d8d08abf86804211413.1694961365.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-at91-usart.c b/drivers/spi/spi-at91-usart.c
index b11d0f993cc761751bbd1b270b798afcd042da4a..1cea8e159344ec82a72be1b4410ee36bd3a95420 100644 (file)
--- a/drivers/spi/spi-at91-usart.c
+++ b/drivers/spi/spi-at91-usart.c
@@ -132,28 +132,14 @@ static int at91_usart_spi_configure_dma(struct spi_controller *ctlr,
        dma_cap_set(DMA_SLAVE, mask);
 
        ctlr->dma_tx = dma_request_chan(dev, "tx");
-       if (IS_ERR_OR_NULL(ctlr->dma_tx)) {
-               if (IS_ERR(ctlr->dma_tx)) {
-                       err = PTR_ERR(ctlr->dma_tx);
-                       goto at91_usart_spi_error_clear;
-               }
-
-               dev_dbg(dev,
-                       "DMA TX channel not available, SPI unable to use DMA\n");
-               err = -EBUSY;
+       if (IS_ERR(ctlr->dma_tx)) {
+               err = PTR_ERR(ctlr->dma_tx);
                goto at91_usart_spi_error_clear;
        }
 
        ctlr->dma_rx = dma_request_chan(dev, "rx");
-       if (IS_ERR_OR_NULL(ctlr->dma_rx)) {
-               if (IS_ERR(ctlr->dma_rx)) {
-                       err = PTR_ERR(ctlr->dma_rx);
-                       goto at91_usart_spi_error;
-               }
-
-               dev_dbg(dev,
-                       "DMA RX channel not available, SPI unable to use DMA\n");
-               err = -EBUSY;
+       if (IS_ERR(ctlr->dma_rx)) {
+               err = PTR_ERR(ctlr->dma_rx);
                goto at91_usart_spi_error;
        }