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tuner_e4k: Fix reference to 65535 vs 65536 

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
This commit is contained in:
Sylvain Munaut 2012-03-29 08:47:51 +02:00
parent 585c6d378a
commit 311885441c
1 changed files with 3 additions and 3 deletions
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6
firmware/src/tuner_e4k.c
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@ -403,7 +403,7 @@ static unsigned int compute_fvco(uint32_t f_osc, uint8_t z, uint16_t x)
* handle the fractional part with integer arithmetic:
* Fvco = Fosc * (Z + X/Y) <=> Fvco = Fosc * Z + (Fosc * X)/Y
* This avoids X/Y = 0. However, then we would overflow a 32bit
* integer, as we cannot hold e.g. 26 MHz * 65535 either.
* integer, as we cannot hold e.g. 26 MHz * 65536 either.
*/
fvco_z = (uint64_t)f_osc * z;
@ -533,9 +533,9 @@ int e4k_compute_pll_params(struct e4k_pll_params *oscp, uint32_t fosc, uint32_t
/* compute fractional part. this will not overflow,
* as fosc(max) = 30MHz and z(max) = 255 */
remainder = intended_fvco - (fosc * z);
/* remainder(max) = 30MHz, E4K_PLL_Y = 65535 -> 64bit! */
/* remainder(max) = 30MHz, E4K_PLL_Y = 65536 -> 64bit! */
x = (remainder * E4K_PLL_Y) / fosc;
/* x(max) as result of this computation is 65535 */
/* x(max) as result of this computation is 65536 */
flo = compute_flo(fosc, z, x, r);
if (flo < 0)