usb: host: xhci-plat: Remove useless DMA-32 fallback configuration
authorChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Sat, 15 Jan 2022 08:06:31 +0000 (09:06 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 26 Jan 2022 13:01:19 +0000 (14:01 +0100)
As stated in [1], dma_set_mask() with a 64-bit mask never fails if
dev->dma_mask is non-NULL.
So, if it fails, the 32 bits case will also fail for the same reason.

Simplify code and remove some dead code accordingly.

[1]: https://lore.kernel.org/linux-kernel/YL3vSPK5DXTNvgdx@infradead.org/#t

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/178f859197bebb385609a7c9458fb972ed312e5d.1642233968.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-plat.c

index c1edcc9..93b3216 100644 (file)
@@ -226,20 +226,13 @@ static int xhci_plat_probe(struct platform_device *pdev)
        if (!sysdev)
                sysdev = &pdev->dev;
 
-       /* Try to set 64-bit DMA first */
        if (WARN_ON(!sysdev->dma_mask))
                /* Platform did not initialize dma_mask */
-               ret = dma_coerce_mask_and_coherent(sysdev,
-                                                  DMA_BIT_MASK(64));
+               ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
        else
                ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
-
-       /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */
-       if (ret) {
-               ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(32));
-               if (ret)
-                       return ret;
-       }
+       if (ret)
+               return ret;
 
        pm_runtime_set_active(&pdev->dev);
        pm_runtime_enable(&pdev->dev);