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authorDavid Howells <dhowells@redhat.com>2013-03-28 22:48:28 +0400
committerSarah Sharp <sarah.a.sharp@linux.intel.com>2013-04-03 21:28:31 +0400
commit6a5d6943fe0e4b1e4c43c3aa1919360f68ae2f9a (patch)
tree9699df081c3ba3734dcca3fec525dc3d49e0e069 /drivers/usb/host/xhci.h
parent505bdbc79d20f8f2a56c02498f079bb23b0ef756 (diff)
downloadlinux-6a5d6943fe0e4b1e4c43c3aa1919360f68ae2f9a.tar.xz
xhci: Use ilog2() rather than __ffs() for calculating SEGMENT_SHIFT
Use ilog2() rather than __ffs() for calculating SEGMENT_SHIFT as ilog2() can be worked out at compile time, whereas __ffs() must be calculated at runtime. Signed-off-by: David Howells <dhowells@redhat.com> cc: Sarah Sharp <sarah.a.sharp@linux.intel.com> cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> cc: linux-usb@vger.kernel.org Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Diffstat (limited to 'drivers/usb/host/xhci.h')
-rw-r--r--drivers/usb/host/xhci.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 63582719e0fb..ca550ddb0b1d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1239,7 +1239,7 @@ union xhci_trb {
/* Allow two commands + a link TRB, along with any reserved command TRBs */
#define MAX_RSVD_CMD_TRBS (TRBS_PER_SEGMENT - 3)
#define SEGMENT_SIZE (TRBS_PER_SEGMENT*16)
-#define SEGMENT_SHIFT (__ffs(SEGMENT_SIZE))
+#define SEGMENT_SHIFT (ilog2(SEGMENT_SIZE))
/* TRB buffer pointers can't cross 64KB boundaries */
#define TRB_MAX_BUFF_SHIFT 16
#define TRB_MAX_BUFF_SIZE (1 << TRB_MAX_BUFF_SHIFT)