DMA-API: usb: ohci-sa1111: add a note about DMA masks

Add a comment to explain why this driver doesn't call any of the DMA
API dma_set_mask() functions.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/usb/host/ohci-sa1111.c b/drivers/usb/host/ohci-sa1111.c
index 17b2a7dad77b81cb8d7edb8e69a97ae490d78a63..aa9e127bbe718d52b8c994910c2c30826f5db06e 100644 (file)
--- a/drivers/usb/host/ohci-sa1111.c
+++ b/drivers/usb/host/ohci-sa1111.c
@@ -185,6 +185,12 @@ static int ohci_hcd_sa1111_probe(struct sa1111_dev *dev)
        if (usb_disabled())
                return -ENODEV;
 
+       /*
+        * We don't call dma_set_mask_and_coherent() here because the
+        * DMA mask has already been appropraitely setup by the core
+        * SA-1111 bus code (which includes bug workarounds.)
+        */
+
        hcd = usb_create_hcd(&ohci_sa1111_hc_driver, &dev->dev, "sa1111");
        if (!hcd)
                return -ENOMEM;