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r82xx: pll tweaks beyond my ken

pull/6/head
Kyle Keen 2014-08-03 14:38:32 -04:00
rodzic d59b178cc1
commit 29d2c849f9
1 zmienionych plików z 13 dodań i 15 usunięć
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28
src/tuner_r82xx.c
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@ -460,7 +460,6 @@ static int r82xx_set_pll(struct r82xx_priv *priv, uint32_t freq)
uint32_t vco_min = 1770000;
uint32_t vco_max = vco_min * 2;
uint32_t freq_khz, pll_ref, pll_ref_khz;
uint16_t n_sdm = 2;
uint16_t sdm = 0;
uint8_t mix_div = 2;
uint8_t div_buf = 0;
@ -492,6 +491,8 @@ static int r82xx_set_pll(struct r82xx_priv *priv, uint32_t freq)
return rc;
/* Calculate divider */
if(freq_khz < vco_min/64) vco_min /= 2;
if(freq_khz >= vco_max/2) vco_max *= 2;
while (mix_div <= 64) {
if (((freq_khz * mix_div) >= vco_min) &&
((freq_khz * mix_div) < vco_max)) {
@ -505,14 +506,16 @@ static int r82xx_set_pll(struct r82xx_priv *priv, uint32_t freq)
mix_div = mix_div << 1;
}
rc = r82xx_read(priv, 0x00, data, sizeof(data));
if (rc < 0)
return rc;
if (priv->cfg->rafael_chip == CHIP_R828D)
vco_power_ref = 1;
/*
rc = r82xx_read(priv, 0x00, data, sizeof(data));
if (rc < 0)
return rc;
vco_fine_tune = (data[4] & 0x30) >> 4;
*/
vco_fine_tune = 2;
if (vco_fine_tune > vco_power_ref)
div_num = div_num - 1;
@ -527,7 +530,10 @@ static int r82xx_set_pll(struct r82xx_priv *priv, uint32_t freq)
nint = vco_freq / (2 * pll_ref);
vco_fra = (vco_freq - 2 * pll_ref * nint) / 1000;
if (nint > ((128 / vco_power_ref) - 1)) {
if (priv->cfg->rafael_chip == CHIP_R828D && nint > 127) {
fprintf(stderr, "[R828D] No valid PLL values for %u Hz!\n", freq);
return -1;
} else if (nint > 76) {
fprintf(stderr, "[R82XX] No valid PLL values for %u Hz!\n", freq);
return -1;
}
@ -553,15 +559,7 @@ static int r82xx_set_pll(struct r82xx_priv *priv, uint32_t freq)
return rc;
/* sdm calculator */
while (vco_fra > 1) {
if (vco_fra > (2 * pll_ref_khz / n_sdm)) {
sdm = sdm + 32768 / (n_sdm / 2);
vco_fra = vco_fra - 2 * pll_ref_khz / n_sdm;
if (n_sdm >= 0x8000)
break;
}
n_sdm <<= 1;
}
sdm = (((vco_freq<<16)+pll_ref) / (2*pll_ref)) & 0xFFFF;
rc = r82xx_write_reg(priv, 0x16, sdm >> 8);
if (rc < 0)