[patch V4 27/31] serial: use parity8 in max3100

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From	zengzhaoxiu@163.com
Newsgroups	linux.kernel
Subject	[patch V4 27/31] serial: use parity8 in max3100
Date	Wed, 29 Jun 2016 19:30:01 +0200
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From: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>

Use parity8(c) instead "hweight8(c) & 1" to improve readability,
and improve performance on some CPUs that without popcount support.

Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
---
 drivers/tty/serial/max3100.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index 5c4c280..a0cc84a 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -155,7 +155,7 @@ static int max3100_do_parity(struct max3100_port *s, u16 c)
 	else
 		c &= 0xff;
 
-	parity = parity ^ (hweight8(c) & 1);
+	parity ^= parity8(c);
 	return parity;
 }
 
-- 
2.7.4

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Re: [patch V4 27/31] serial: use parity32 in max3100 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-06-25 19:30 +0200
  [patch V4 27/31] serial: use parity8 in max3100 zengzhaoxiu@163.com - 2016-06-29 17:20 +0200
    Re: [patch V4 27/31] serial: use parity8 in max3100 Greg KH <gregkh@linuxfoundation.org> - 2016-06-29 18:50 +0200
      [patch V4 27/31] serial: use parity8 in max3100 zengzhaoxiu@163.com - 2016-06-29 19:30 +0200

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