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-rw-r--r--drivers/media/dvb/frontends/atbm8830.c19
1 files changed, 14 insertions, 5 deletions
diff --git a/drivers/media/dvb/frontends/atbm8830.c b/drivers/media/dvb/frontends/atbm8830.c
index d77684893d9..59881a5944e 100644
--- a/drivers/media/dvb/frontends/atbm8830.c
+++ b/drivers/media/dvb/frontends/atbm8830.c
@@ -19,6 +19,7 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
+#include <asm/div64.h>
#include "dvb_frontend.h"
#include "atbm8830.h"
@@ -102,8 +103,12 @@ static inline int atbm8830_reglatch_lock(struct atbm_state *priv, int lock)
static int set_osc_freq(struct atbm_state *priv, u32 freq /*in kHz*/)
{
u32 val;
+ u64 t;
- val = (u64)0x100000 * freq / 30400;
+ /* 0x100000 * freq / 30.4MHz */
+ t = (u64)0x100000 * freq;
+ do_div(t, 30400);
+ val = t;
atbm8830_write_reg(priv, REG_OSC_CLK, val);
atbm8830_write_reg(priv, REG_OSC_CLK + 1, val >> 8);
@@ -116,14 +121,18 @@ static int set_if_freq(struct atbm_state *priv, u32 freq /*in kHz*/)
{
u32 fs = priv->config->osc_clk_freq;
- double t;
+ u64 t;
u32 val;
u8 dat;
- t = 2 * 3.141593 * (freq - fs) / fs * (1 << 22);
- val = t;
-
if (freq != 0) {
+ /* 2 * PI * (freq - fs) / fs * (2 ^ 22) */
+ t = (u64) 2 * 31416 * (freq - fs);
+ t <<= 22;
+ do_div(t, fs);
+ do_div(t, 1000);
+ val = t;
+
atbm8830_write_reg(priv, REG_TUNER_BASEBAND, 1);
atbm8830_write_reg(priv, REG_IF_FREQ, val);
atbm8830_write_reg(priv, REG_IF_FREQ+1, val >> 8);