diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/dvb/frontends/atbm8830.c | 19 |
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); |