ASoC: wm8994: Lower AIFnCLK divisor when dropping to 32kHz

When lowering SYSCLK to 50kHz for accessory detection also lower the
AIFnCLK divisor to normalise the clocking configuration within the
device. This will not disrupt audio as we cannot support active audio
with such a low SYSCLK.

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

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 1d1b43fe1722205f6939b38b05fc1f537263d9c0..ab332e380fb3f58f570f16297632d05699c16eb7 100644 (file)
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -2258,6 +2258,18 @@ out:
 
        configure_clock(codec);
 
+       /*
+        * If SYSCLK will be less than 50kHz adjust AIFnCLK dividers
+        * for detection.
+        */
+       if (max(wm8994->aifclk[0], wm8994->aifclk[1]) < 50000) {
+               dev_dbg(codec->dev, "Configuring AIFs for 128fs\n");
+               snd_soc_update_bits(codec, WM8994_AIF1_RATE,
+                                   WM8994_AIF1CLK_RATE_MASK, 0x1);
+               snd_soc_update_bits(codec, WM8994_AIF2_RATE,
+                                   WM8994_AIF2CLK_RATE_MASK, 0x1);
+       }
+
        return 0;
 }