forked from Minki/linux
ASoC: arizona: Prefer lower FRATIO in pseudo-fractional mode
When setting up an FLL in pseudo-fractional mode it is preferred to use a lower FRATIO if possible to give a higher reference clock frequency. This patch swaps the two loops in arizona_calc_fratio() so that lower FRATIOs are tried first. The decrementing loop is also changed to start from init_ratio because the original settings might already give a fractional value for N.K Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
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@ -2037,7 +2037,21 @@ static int arizona_calc_fratio(struct arizona_fll *fll,
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init_ratio, Fref, refdiv);
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while (div <= ARIZONA_FLL_MAX_REFDIV) {
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for (ratio = init_ratio; ratio <= ARIZONA_FLL_MAX_FRATIO;
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/* start from init_ratio because this may already give a
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* fractional N.K
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*/
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for (ratio = init_ratio; ratio > 0; ratio--) {
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if (target % (ratio * Fref)) {
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cfg->refdiv = refdiv;
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cfg->fratio = ratio - 1;
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arizona_fll_dbg(fll,
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"pseudo: found fref=%u refdiv=%d(%d) ratio=%d\n",
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Fref, refdiv, div, ratio);
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return ratio;
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}
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}
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for (ratio = init_ratio + 1; ratio <= ARIZONA_FLL_MAX_FRATIO;
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ratio++) {
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if ((ARIZONA_FLL_VCO_CORNER / 2) /
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(fll->vco_mult * ratio) < Fref) {
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@ -2063,17 +2077,6 @@ static int arizona_calc_fratio(struct arizona_fll *fll,
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}
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}
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for (ratio = init_ratio - 1; ratio > 0; ratio--) {
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if (target % (ratio * Fref)) {
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cfg->refdiv = refdiv;
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cfg->fratio = ratio - 1;
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arizona_fll_dbg(fll,
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"pseudo: found fref=%u refdiv=%d(%d) ratio=%d\n",
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Fref, refdiv, div, ratio);
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return ratio;
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}
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}
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div *= 2;
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Fref /= 2;
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refdiv++;
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