staging: vt6655: CARDqGetNextTBTT calculate qwTSF using do_div

Use do_div to compute equation as shown replacing existing code.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Malcolm Priestley 2014-08-10 12:21:59 +01:00 committed by Greg Kroah-Hartman
parent 0fc2a76eef
commit 989ae8601b
1 changed files with 10 additions and 19 deletions

View File

@ -1995,27 +1995,18 @@ bool CARDbGetCurrentTSF(void __iomem *dwIoBase, u64 *pqwCurrTSF)
*/
u64 CARDqGetNextTBTT(u64 qwTSF, unsigned short wBeaconInterval)
{
unsigned int uLowNextTBTT;
unsigned int uHighRemain, uLowRemain;
unsigned int uBeaconInterval;
u32 beacon_int;
uBeaconInterval = wBeaconInterval * 1024;
// Next TBTT = ((local_current_TSF / beacon_interval) + 1) * beacon_interval
uLowNextTBTT = ((qwTSF & 0xffffffffULL) >> 10) << 10;
// low dword (mod) bcn
uLowRemain = (uLowNextTBTT) % uBeaconInterval;
// high dword (mod) bcn
uHighRemain = (((0xffffffff % uBeaconInterval) + 1) * (u32)(qwTSF >> 32))
% uBeaconInterval;
uLowRemain = (uHighRemain + uLowRemain) % uBeaconInterval;
uLowRemain = uBeaconInterval - uLowRemain;
beacon_int = wBeaconInterval * 1024;
// check if carry when add one beacon interval
if ((~uLowNextTBTT) < uLowRemain)
qwTSF = ((qwTSF >> 32) + 1) << 32;
qwTSF = (qwTSF & 0xffffffff00000000ULL) |
(u64)(uLowNextTBTT + uLowRemain);
/* Next TBTT =
* ((local_current_TSF / beacon_interval) + 1) * beacon_interval
*/
if (beacon_int) {
do_div(qwTSF, beacon_int);
qwTSF += 1;
qwTSF *= beacon_int;
}
return qwTSF;
}