From ff74ad639e81ccd39d132ba67329b9b74b1bdf3f Mon Sep 17 00:00:00 2001
From: Daniel Baluta <daniel.baluta@nxp.com>
Date: Mon, 13 Mar 2017 18:57:23 +0200
Subject: [PATCH 1/2] MLK-14277: ASoC: codec: wm8960: Refactor sysclk freq
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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>
---
 sound/soc/codecs/wm8960.c | 82 +++++++++++++++++++++++++++++++++++------------
 1 file changed, 62 insertions(+), 20 deletions(-)

diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
index e1429e3..c01f3de 100644
--- 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
+ * @_i: sysclk_divs index for found sysclk
+ * @_j: dac_divs index for found lrclk
+ * @_k: bclk_divs index for found bclk
+ *
+ * Returns:
+ * -1, in case no sysclk frequency available found
+ *  0, in case an exact match is found. See @_i, @_j, @_k
+ *
+ */
+int wm8960_configure_sysclk(struct wm8960_priv *wm8960, int mclk,
+             int *_i, int *_j, int *_k)
+{
+   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) {
+                   *_i = i;
+                   *_j = j;
+                   *_k = 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,
@@ -643,27 +702,10 @@ 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) {
+       else if (wm8960->clk_id != WM8960_SYSCLK_AUTO) {
            dev_err(codec->dev, "failed to configure clock\n");
            return -EINVAL;
        }
--
2.7.4