ASoC: adau: Factor out shared PLL configuration code

Multiple devices from the ADAU family share the same PLL structure and
configuration register layout. Introduce a new helper module that can be
used to calculated the PLL configuration registers based on a specified
input frequency and the desired output frequency of the PLL.

The ADAU1761/ADAU1781 and ADAU1373 drivers are updated to make use of this
new helper module. But future drivers for additional devices from the ADAU
family are also expected to make use of it.

In anticipation of sharing more infrastructure code between different
devices from the ADAU family the new module is called adau-utils.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 10 insertions, 28 deletions

diff --git a/sound/soc/codecs/adau1373.c b/sound/soc/codecs/adau1373.c
index fe1353a797b9..1556b360fa15 100644
--- a/sound/soc/codecs/adau1373.c
+++ b/sound/soc/codecs/adau1373.c
@@ -23,6 +23,7 @@
 #include <sound/adau1373.h>
 
 #include "adau1373.h"
+#include "adau-utils.h"
 
 struct adau1373_dai {
 	unsigned int clk_src;
@@ -1254,7 +1255,8 @@ static int adau1373_set_pll(struct snd_soc_codec *codec, int pll_id,
 {
 	struct adau1373 *adau1373 = snd_soc_codec_get_drvdata(codec);
 	unsigned int dpll_div = 0;
-	unsigned int x, r, n, m, i, j, mode;
+	uint8_t pll_regs[5];
+	int ret;
 
 	switch (pll_id) {
 	case ADAU1373_PLL1:
@@ -1295,27 +1297,8 @@ static int adau1373_set_pll(struct snd_soc_codec *codec, int pll_id,
 		dpll_div++;
 	}
 
-	if (freq_out % freq_in != 0) {
-		/* fout = fin * (r + (n/m)) / x */
-		x = DIV_ROUND_UP(freq_in, 13500000);
-		freq_in /= x;
-		r = freq_out / freq_in;
-		i = freq_out % freq_in;
-		j = gcd(i, freq_in);
-		n = i / j;
-		m = freq_in / j;
-		x--;
-		mode = 1;
-	} else {
-		/* fout = fin / r */
-		r = freq_out / freq_in;
-		n = 0;
-		m = 0;
-		x = 0;
-		mode = 0;
-	}
-
-	if (r < 2 || r > 8 || x > 3 || m > 0xffff || n > 0xffff)
+	ret = adau_calc_pll_cfg(freq_in, freq_out, pll_regs);
+	if (ret)
 		return -EINVAL;
 
 	if (dpll_div) {
@@ -1330,12 +1313,11 @@ static int adau1373_set_pll(struct snd_soc_codec *codec, int pll_id,
 
 	regmap_write(adau1373->regmap, ADAU1373_DPLL_CTRL(pll_id),
 		(source << 4) | dpll_div);
-	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL1(pll_id), (m >> 8) & 0xff);
-	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL2(pll_id), m & 0xff);
-	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL3(pll_id), (n >> 8) & 0xff);
-	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL4(pll_id), n & 0xff);
-	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL5(pll_id),
-		(r << 3) | (x << 1) | mode);
+	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL1(pll_id), pll_regs[0]);
+	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL2(pll_id), pll_regs[1]);
+	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL3(pll_id), pll_regs[2]);
+	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL4(pll_id), pll_regs[3]);
+	regmap_write(adau1373->regmap, ADAU1373_PLL_CTRL5(pll_id), pll_regs[4]);
 
 	/* Set sysclk to pll_rate / 4 */
 	regmap_update_bits(adau1373->regmap, ADAU1373_CLK_SRC_DIV(pll_id), 0x3f, 0x09);