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V4L/DVB: lgs8gxx: Use shifts rather than multiply/divide when possible

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If val is a u64, then following:

	val *= (u64)1 << 32;
	val /= (u64)1 << 32;

should surely be better represented as:

	val <<= 32;
	val >>= 32;

Especially as, for the division, the compiler might want to actually do a
division:

drivers/built-in.o: In function `lgs8gxx_get_afc_phase':
drivers/media/dvb/frontends/lgs8gxx.c:250: undefined reference to `__udivdi3'

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
David Howells
2009-12-11 13:11:05 -03:00
committed by Mauro Carvalho Chehab
parent 5bf5834738
commit 3ab1b9cecd
1 changed files with 2 additions and 2 deletions
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4
drivers/media/dvb/frontends/lgs8gxx.c
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@@ -199,7 +199,7 @@ static int lgs8gxx_set_if_freq(struct lgs8gxx_state *priv, u32 freq /*in kHz*/)
val = freq; val = freq;
if (freq != 0) { if (freq != 0) {
val *= (u64)1 << 32; val <<= 32;
if (if_clk != 0) if (if_clk != 0)
do_div(val, if_clk); do_div(val, if_clk);
v32 = val & 0xFFFFFFFF; v32 = val & 0xFFFFFFFF;
@@ -246,7 +246,7 @@ static int lgs8gxx_get_afc_phase(struct lgs8gxx_state *priv)
val = v32; val = v32;
val *= priv->config->if_clk_freq; val *= priv->config->if_clk_freq;
val /= (u64)1 << 32; val >>= 32;
dprintk("AFC = %u kHz\n", (u32)val); dprintk("AFC = %u kHz\n", (u32)val);
return 0; return 0;
} }