From: Lynn Lei <lynnl.wit@gmail.com>
To: sudipm.mukherjee@gmail.com
Cc: teddy.wang@siliconmotion.com, gregkh@linuxfoundation.org,
linux-fbdev@vger.kernel.org, devel@driverdev.osuosl.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] staging: sm750fb: refactor the clock frequency calculation method
Date: Sun, 2 Jul 2017 20:24:26 +0800 [thread overview]
Message-ID: <20170702122426.GA17561@lynnl.wit> (raw)
speed up calculation by merging two divisions into one.
Signed-off-by: Lynn Lei <lynnl.wit@gmail.com>
---
drivers/staging/sm750fb/ddk750_chip.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/staging/sm750fb/ddk750_chip.c b/drivers/staging/sm750fb/ddk750_chip.c
index c51761221131..5970c3792f27 100644
--- a/drivers/staging/sm750fb/ddk750_chip.c
+++ b/drivers/staging/sm750fb/ddk750_chip.c
@@ -44,7 +44,7 @@ static unsigned int get_mxclk_freq(void)
OD = (pll_reg & PLL_CTRL_OD_MASK) >> PLL_CTRL_OD_SHIFT;
POD = (pll_reg & PLL_CTRL_POD_MASK) >> PLL_CTRL_POD_SHIFT;
- return DEFAULT_INPUT_CLOCK * M / N / (1 << OD) / (1 << POD);
+ return DEFAULT_INPUT_CLOCK * M / N / (1 << (OD + POD));
}
/*
--
2.13.2
next reply other threads:[~2017-07-02 12:24 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-02 12:24 Lynn Lei [this message]
2017-07-03 6:21 ` [PATCH] staging: sm750fb: refactor the clock frequency calculation method Greg KH
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