ASoC: codec: wm8960: Refactor sysclk freq search

Add a separate function for finding (sysclk, lrclk, bclk)
when the clock is auto or mclk. This makes code easier to
read and reduces the indentation level in wm8960_configure_clocking.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
index 3bf081a7e450993324bb435887aedd23d0bc578f..25a4a11929fe1deb83d881b6e13cffa919bb6499 100644 (file)
--- a/sound/soc/codecs/wm8960.c
+++ b/sound/soc/codecs/wm8960.c
@@ -604,12 +604,71 @@ static const int bclk_divs[] = {
        120, 160, 220, 240, 320, 320, 320
 };
 
+/**
+ * wm8960_configure_sysclk - checks if there is a sysclk frequency available
+ *     The sysclk must be chosen such that:
+ *             - sysclk     = MCLK / sysclk_divs
+ *             - lrclk      = sysclk / dac_divs
+ *             - 10 * bclk  = sysclk / bclk_divs
+ *
+ * @wm8960_priv: wm8960 codec private data
+ * @mclk: MCLK used to derive sysclk
+ * @sysclk_idx: sysclk_divs index for found sysclk
+ * @dac_idx: dac_divs index for found lrclk
+ * @bclk_idx: bclk_divs index for found bclk
+ *
+ * Returns:
+ * -1, in case no sysclk frequency available found
+ *  0, in case an exact (@sysclk_idx, @dac_idx, @bclk_idx) match is found
+ */
+static
+int wm8960_configure_sysclk(struct wm8960_priv *wm8960, int mclk,
+                           int *sysclk_idx, int *dac_idx, int *bclk_idx)
+{
+       int sysclk, bclk, lrclk;
+       int i, j, k;
+       int diff;
+
+       bclk = wm8960->bclk;
+       lrclk = wm8960->lrclk;
+
+       /* check if the sysclk frequency is available. */
+       for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
+               if (sysclk_divs[i] == -1)
+                       continue;
+               sysclk = mclk / sysclk_divs[i];
+               for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {
+                       if (sysclk != dac_divs[j] * lrclk)
+                               continue;
+                       for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k) {
+                               diff = sysclk - bclk * bclk_divs[k] / 10;
+                               if (diff == 0) {
+                                       *sysclk_idx = i;
+                                       *dac_idx = j;
+                                       *bclk_idx = k;
+                                       break;
+                               }
+                       }
+                       if (k != ARRAY_SIZE(bclk_divs))
+                               break;
+               }
+               if (j != ARRAY_SIZE(dac_divs))
+                       break;
+       }
+
+       if (i != ARRAY_SIZE(sysclk_divs))
+               return 0;
+
+       return -1;
+}
+
 static int wm8960_configure_clocking(struct snd_soc_codec *codec)
 {
        struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
        int sysclk, bclk, lrclk, freq_out, freq_in;
        u16 iface1 = snd_soc_read(codec, WM8960_IFACE1);
        int i, j, k;
+       int ret;
 
        if (!(iface1 & (1<<6))) {
                dev_dbg(codec->dev,
@@ -643,25 +702,8 @@ static int wm8960_configure_clocking(struct snd_soc_codec *codec)
        }
 
        if (wm8960->clk_id != WM8960_SYSCLK_PLL) {
-               /* check if the sysclk frequency is available. */
-               for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
-                       if (sysclk_divs[i] == -1)
-                               continue;
-                       sysclk = freq_out / sysclk_divs[i];
-                       for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {
-                               if (sysclk != dac_divs[j] * lrclk)
-                                       continue;
-                               for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k)
-                                       if (sysclk == bclk * bclk_divs[k] / 10)
-                                               break;
-                               if (k != ARRAY_SIZE(bclk_divs))
-                                       break;
-                       }
-                       if (j != ARRAY_SIZE(dac_divs))
-                               break;
-               }
-
-               if (i != ARRAY_SIZE(sysclk_divs)) {
+               ret = wm8960_configure_sysclk(wm8960, freq_out, &i, &j, &k);
+               if (ret == 0) {
                        goto configure_clock;
                } else if (wm8960->clk_id != WM8960_SYSCLK_AUTO) {
                        dev_err(codec->dev, "failed to configure clock\n");