ASoC: wm8994: Implement FLL bypass support

Later WM8994 class devices can bypass the FLL from BCLK. Do this
automatically when the FLL input and output frequencies match up.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 20 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 8b05e78b11c..01ecdb56ecd 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -1977,6 +1977,14 @@ static int _wm8994_set_fll(struct snd_soc_codec *codec, int id, int src,
         snd_soc_update_bits(codec, WM8994_FLL1_CONTROL_1 + reg_offset,
                             WM8994_FLL1_ENA, 0);
 
+        if (wm8994->fll_byp && src == WM8994_FLL_SRC_BCLK &&
+            freq_in == freq_out) {
+                dev_dbg(codec->dev, "Bypassing FLL%d\n", id + 1);
+                snd_soc_update_bits(codec, WM8994_FLL1_CONTROL_5 + reg_offset,
+                                    WM8958_FLL1_BYP, WM8958_FLL1_BYP);
+                goto out;
+        }
+
         reg = (fll.outdiv << WM8994_FLL1_OUTDIV_SHIFT) |
                 (fll.fll_fratio << WM8994_FLL1_FRATIO_SHIFT);
         snd_soc_update_bits(codec, WM8994_FLL1_CONTROL_2 + reg_offset,
@@ -1991,6 +1999,7 @@ static int _wm8994_set_fll(struct snd_soc_codec *codec, int id, int src,
                                     fll.n << WM8994_FLL1_N_SHIFT);
 
         snd_soc_update_bits(codec, WM8994_FLL1_CONTROL_5 + reg_offset,
+                            WM8958_FLL1_BYP |
                             WM8994_FLL1_REFCLK_DIV_MASK |
                             WM8994_FLL1_REFCLK_SRC_MASK,
                             (fll.clk_ref_div << WM8994_FLL1_REFCLK_DIV_SHIFT) |
@@ -2053,6 +2062,7 @@ static int _wm8994_set_fll(struct snd_soc_codec *codec, int id, int src,
                 }
         }
 
+out:
         wm8994->fll[id].in = freq_in;
         wm8994->fll[id].out = freq_out;
         wm8994->fll[id].src = src;
@@ -3579,6 +3589,14 @@ static int wm8994_codec_probe(struct snd_soc_codec *codec)
         case WM8958:
                 wm8994->hubs.dcs_readback_mode = 1;
                 wm8994->hubs.hp_startup_mode = 1;
+
+                switch (wm8994->revision) {
+                case 0:
+                        break;
+                default:
+                        wm8994->fll_byp = true;
+                        break;
+                }
                 break;
 
         case WM1811:
@@ -3586,6 +3604,7 @@ static int wm8994_codec_probe(struct snd_soc_codec *codec)
                 wm8994->hubs.no_series_update = 1;
                 wm8994->hubs.hp_startup_mode = 1;
                 wm8994->hubs.no_cache_class_w = true;
+                wm8994->fll_byp = true;
 
                 switch (wm8994->revision) {
                 case 0:
diff --git a/sound/soc/codecs/wm8994.h b/sound/soc/codecs/wm8994.h
index c724112998d..91650bba205 100644
--- a/sound/soc/codecs/wm8994.h
+++ b/sound/soc/codecs/wm8994.h
@@ -79,6 +79,7 @@ struct wm8994_priv {
         struct wm8994_fll_config fll[2], fll_suspend[2];
         struct completion fll_locked[2];
         bool fll_locked_irq;
+        bool fll_byp;
 
         int vmid_refcount;
         int active_refcount;