ASoC: arizona: Fixed a bug in FLL fractional calculation (01f58153) · Commits · 戴 / test

Previously arizona_calc_fll() was checking if the target frequency is exactly divisible by reference frequency, but should have been product of the ratio and the reference frequency. Also scale down the Lamba and Theta coefficients be under 16-bits in order to match the registers. Signed-off-by:

Ryo Tsutsui <ryo.tsutsui@wolfsonmicro.com> Signed-off-by:

Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by:

Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@vger.kernel.org

sound/soc/codecs/arizona.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -910,7 +910,7 @@ static int arizona_calc_fll(struct arizona_fll *fll,

		cfg->n = target / (ratio * Fref);

		if (target % Fref) {
		if (target % (ratio * Fref)) {
		gcd_fll = gcd(target, ratio * Fref);
		arizona_fll_dbg(fll, "GCD=%u\n", gcd_fll);

		@@ -922,6 +922,15 @@ static int arizona_calc_fll(struct arizona_fll *fll,
		cfg->lambda = 0;
		}

		/* Round down to 16bit range with cost of accuracy lost.
		* Denominator must be bigger than numerator so we only
		* take care of it.
		*/
		while (cfg->lambda >= (1 << 16)) {
		cfg->theta >>= 1;
		cfg->lambda >>= 1;
		}

		arizona_fll_dbg(fll, "N=%x THETA=%x LAMBDA=%x\n",
		cfg->n, cfg->theta, cfg->lambda);
		arizona_fll_dbg(fll, "FRATIO=%x(%d) OUTDIV=%x REFCLK_DIV=%x\n",

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