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23 October 2021, 00:29:24 UTC
Revision 0020d3ef915fc01a0184bc96eeb3c240bded5d8e authored by Hans Verkuil on 30 March 2006, 22:50:34 UTC, committed by Mauro Carvalho Chehab on 02 April 2006, 07:56:06 UTC 
V4L/DVB (3693): Fix msp3400c and bttv stereo/mono/bilingual detection/handling
 
- msp3400c did not detect the second carrier, thus being always mono.
- properly mute the msp3400c while detecting the carrier.
- fix checks on the presence of scart2/3 inputs and scart 2 output.
- implement proper audio mode fallbacks for msp3400c/d, identical to the
  way msp3400g works.
- MODE_STEREO no longer produces dual languages when set for a bilingual
  transmission, instead it falls back to LANG1. Use LANG1_LANG2 to hear
  both languages of a bilingual transmission. This is much more intuitive
  for the user and is in accordance with the preferred usage in the v4l2
  specification.
- bttv tried to implement v4l2 calls with v4l1 calls to the i2c devices,
  completely mangling the audmode/rxsubchans handling. v4l2 calls now do
  v4l2 calls to the i2c devices.
- fixed broken i2c_vidiocschan in bttv.
- add start/end lines to LOG_STATUS.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
1 parent 9bc7400
Raw File
Tip revision: 0020d3ef915fc01a0184bc96eeb3c240bded5d8e authored by Hans Verkuil on 30 March 2006, 22:50:34 UTC
V4L/DVB (3693): Fix msp3400c and bttv stereo/mono/bilingual detection/handling
Tip revision: 0020d3e
hweight.c 
#include <linux/module.h>
#include <asm/types.h>

/**
 * hweightN - returns the hamming weight of a N-bit word
 * @x: the word to weigh
 *
 * The Hamming Weight of a number is the total number of bits set in it.
 */

unsigned int hweight32(unsigned int w)
{
	unsigned int res = w - ((w >> 1) & 0x55555555);
	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
	res = (res + (res >> 4)) & 0x0F0F0F0F;
	res = res + (res >> 8);
	return (res + (res >> 16)) & 0x000000FF;
}
EXPORT_SYMBOL(hweight32);

unsigned int hweight16(unsigned int w)
{
	unsigned int res = w - ((w >> 1) & 0x5555);
	res = (res & 0x3333) + ((res >> 2) & 0x3333);
	res = (res + (res >> 4)) & 0x0F0F;
	return (res + (res >> 8)) & 0x00FF;
}
EXPORT_SYMBOL(hweight16);

unsigned int hweight8(unsigned int w)
{
	unsigned int res = w - ((w >> 1) & 0x55);
	res = (res & 0x33) + ((res >> 2) & 0x33);
	return (res + (res >> 4)) & 0x0F;
}
EXPORT_SYMBOL(hweight8);

unsigned long hweight64(__u64 w)
{
#if BITS_PER_LONG == 32
	return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w);
#elif BITS_PER_LONG == 64
	__u64 res = w - ((w >> 1) & 0x5555555555555555ul);
	res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
	res = (res + (res >> 4)) & 0x0F0F0F0F0F0F0F0Ful;
	res = res + (res >> 8);
	res = res + (res >> 16);
	return (res + (res >> 32)) & 0x00000000000000FFul;
#else
#error BITS_PER_LONG not defined
#endif
}
EXPORT_SYMBOL(hweight64);
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