drivers: fix dma_get_required_mask

commit: e88a0c2ca81207a75afe5bbb8020541dabf606ac
Date: Sun, 9 Mar 2008 11:57:56 -0500
Subject: drivers: fix dma_get_required_mask

There's a bug in the current implementation of dma_get_required_mask()
where it ands the returned mask with the current device mask.  This
rather defeats the purpose if you're using the call to determine what
your mask should be (since you will at that time have the default
DMA_32BIT_MASK).  This bug results in any driver that uses this function
*always* getting a 32 bit mask, which is wrong.

Fix by removing the and with dev->dma_mask.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index fb56092414821645342071f5c0da32ef2a486b4b..39d8b7b4c140c2e4584ca6e716ca537689a9628f 100644 (file)
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -647,7 +647,7 @@ u64 dma_get_required_mask(struct device *dev)
                high_totalram += high_totalram - 1;
                mask = (((u64)high_totalram) << 32) + 0xffffffff;
        }
-       return mask & *dev->dma_mask;
+       return mask;
 }
 EXPORT_SYMBOL_GPL(dma_get_required_mask);
 #endif