[alsa-devel] [PATCH 4/4] ASoC: arizona: Optimise FLL loop gains
For optimal performance the FLL loop gain should be adjusted depending on the frequency of the input clock for the loop.
Signed-off-by: Mark Brown broonie@opensource.wolfsonmicro.com --- sound/soc/codecs/arizona.c | 43 +++++++++++++++++++++++++++++++++++++++---- 1 file changed, 39 insertions(+), 4 deletions(-)
diff --git a/sound/soc/codecs/arizona.c b/sound/soc/codecs/arizona.c index 41c116f..29dd641 100644 --- a/sound/soc/codecs/arizona.c +++ b/sound/soc/codecs/arizona.c @@ -1175,6 +1175,16 @@ static struct { { 1000000, 13500000, 0, 1 }, };
+static struct { + unsigned int min; + unsigned int max; + u16 gain; +} fll_gains[] = { + { 0, 256000, 0 }, + { 256000, 1000000, 2 }, + { 1000000, 13500000, 4 }, +}; + struct arizona_fll_cfg { int n; int theta; @@ -1182,6 +1192,7 @@ struct arizona_fll_cfg { int refdiv; int outdiv; int fratio; + int gain; };
static int arizona_calc_fll(struct arizona_fll *fll, @@ -1241,6 +1252,18 @@ static int arizona_calc_fll(struct arizona_fll *fll, return -EINVAL; }
+ for (i = 0; i < ARRAY_SIZE(fll_gains); i++) { + if (fll_gains[i].min <= Fref && Fref <= fll_gains[i].max) { + cfg->gain = fll_gains[i].gain; + break; + } + } + if (i == ARRAY_SIZE(fll_gains)) { + arizona_fll_err(fll, "Unable to find gain for Fref=%uHz\n", + Fref); + return -EINVAL; + } + cfg->n = target / (ratio * Fref);
if (target % (ratio * Fref)) { @@ -1268,13 +1291,15 @@ static int arizona_calc_fll(struct arizona_fll *fll, cfg->n, cfg->theta, cfg->lambda); arizona_fll_dbg(fll, "FRATIO=%x(%d) OUTDIV=%x REFCLK_DIV=%x\n", cfg->fratio, cfg->fratio, cfg->outdiv, cfg->refdiv); + arizona_fll_dbg(fll, "GAIN=%d\n", cfg->gain);
return 0;
}
static void arizona_apply_fll(struct arizona *arizona, unsigned int base, - struct arizona_fll_cfg *cfg, int source) + struct arizona_fll_cfg *cfg, int source, + bool sync) { regmap_update_bits(arizona->regmap, base + 3, ARIZONA_FLL1_THETA_MASK, cfg->theta); @@ -1289,6 +1314,15 @@ static void arizona_apply_fll(struct arizona *arizona, unsigned int base, cfg->refdiv << ARIZONA_FLL1_CLK_REF_DIV_SHIFT | source << ARIZONA_FLL1_CLK_REF_SRC_SHIFT);
+ if (sync) + regmap_update_bits(arizona->regmap, base + 0x7, + ARIZONA_FLL1_GAIN_MASK, + cfg->gain << ARIZONA_FLL1_GAIN_SHIFT); + else + regmap_update_bits(arizona->regmap, base + 0x9, + ARIZONA_FLL1_GAIN_MASK, + cfg->gain << ARIZONA_FLL1_GAIN_SHIFT); + regmap_update_bits(arizona->regmap, base + 2, ARIZONA_FLL1_CTRL_UPD | ARIZONA_FLL1_N_MASK, ARIZONA_FLL1_CTRL_UPD | cfg->n); @@ -1326,17 +1360,18 @@ static void arizona_enable_fll(struct arizona_fll *fll, ARIZONA_FLL1_OUTDIV_MASK, ref->outdiv << ARIZONA_FLL1_OUTDIV_SHIFT);
- arizona_apply_fll(arizona, fll->base, ref, fll->ref_src); + arizona_apply_fll(arizona, fll->base, ref, fll->ref_src, + false); if (fll->sync_src >= 0) arizona_apply_fll(arizona, fll->base + 0x10, sync, - fll->sync_src); + fll->sync_src, true); } else if (fll->sync_src >= 0) { regmap_update_bits(arizona->regmap, fll->base + 5, ARIZONA_FLL1_OUTDIV_MASK, sync->outdiv << ARIZONA_FLL1_OUTDIV_SHIFT);
arizona_apply_fll(arizona, fll->base, sync, - fll->sync_src); + fll->sync_src, false); } else { arizona_fll_err(fll, "No clocks provided\n"); return;
participants (1)
-
Mark Brown