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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/media/dvb-core/dvb_math.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/media/dvb-core/dvb_math.h')
-rw-r--r-- | kernel/drivers/media/dvb-core/dvb_math.h | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/kernel/drivers/media/dvb-core/dvb_math.h b/kernel/drivers/media/dvb-core/dvb_math.h new file mode 100644 index 000000000..aecc867e9 --- /dev/null +++ b/kernel/drivers/media/dvb-core/dvb_math.h @@ -0,0 +1,58 @@ +/* + * dvb-math provides some complex fixed-point math + * operations shared between the dvb related stuff + * + * Copyright (C) 2006 Christoph Pfister (christophpfister@gmail.com) + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __DVB_MATH_H +#define __DVB_MATH_H + +#include <linux/types.h> + +/** + * computes log2 of a value; the result is shifted left by 24 bits + * + * to use rational values you can use the following method: + * intlog2(value) = intlog2(value * 2^x) - x * 2^24 + * + * example: intlog2(8) will give 3 << 24 = 3 * 2^24 + * example: intlog2(9) will give 3 << 24 + ... = 3.16... * 2^24 + * example: intlog2(1.5) = intlog2(3) - 2^24 = 0.584... * 2^24 + * + * @param value The value (must be != 0) + * @return log2(value) * 2^24 + */ +extern unsigned int intlog2(u32 value); + +/** + * computes log10 of a value; the result is shifted left by 24 bits + * + * to use rational values you can use the following method: + * intlog10(value) = intlog10(value * 10^x) - x * 2^24 + * + * example: intlog10(1000) will give 3 << 24 = 3 * 2^24 + * due to the implementation intlog10(1000) might be not exactly 3 * 2^24 + * + * look at intlog2 for similar examples + * + * @param value The value (must be != 0) + * @return log10(value) * 2^24 + */ +extern unsigned int intlog10(u32 value); + +#endif |