ASoC: wm_hubs: Special case headphones for digital paths in more use cases

The optimisations which we can do with caching the headphone DCS result in
wm_hubs have only been enabled in cases where class W is enabled. However,
there are more use cases which can benefit from the cache, especially with
WM8994 series devices with their more advanced digital routing.

Rather than keying off the class W information from the CODECs have a
check in wm_hubs for a suitable path and use that to determine if we can
deploy our headphone optimisations.

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

4 files changed, 45 insertions, 14 deletions

diff --git a/sound/soc/codecs/wm8993.c b/sound/soc/codecs/wm8993.c
index d256a9340644..8bb005926aa0 100644
--- a/sound/soc/codecs/wm8993.c
+++ b/sound/soc/codecs/wm8993.c
@@ -852,7 +852,6 @@ static int class_w_put(struct snd_kcontrol *kcontrol,
                                             0);
                 }
                 wm8993->class_w_users++;
-                wm8993->hubs_data.class_w = true;
         }
 
         /* Implement the change */
@@ -869,7 +868,6 @@ static int class_w_put(struct snd_kcontrol *kcontrol,
                                             WM8993_CP_DYN_V);
                 }
                 wm8993->class_w_users--;
-                wm8993->hubs_data.class_w = false;
         }
 
         dev_dbg(codec->dev, "Indirect DAC use count now %d\n",
diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index a22c29386243..2475e1c10334 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -998,13 +998,11 @@ static void wm8994_update_class_w(struct snd_soc_codec *codec)
                                     WM8994_CP_DYN_PWR |
                                     WM8994_CP_DYN_SRC_SEL_MASK,
                                     source | WM8994_CP_DYN_PWR);
-                wm8994->hubs.class_w = true;
 
         } else {
                 dev_dbg(codec->dev, "Class W disabled\n");
                 snd_soc_update_bits(codec, WM8994_CLASS_W_1,
                                     WM8994_CP_DYN_PWR, 0);
-                wm8994->hubs.class_w = false;
         }
 }
 
@@ -3609,7 +3607,7 @@ static int wm8994_codec_probe(struct snd_soc_codec *codec)
                 wm8994->hubs.dcs_readback_mode = 2;
                 wm8994->hubs.no_series_update = 1;
                 wm8994->hubs.hp_startup_mode = 1;
-                wm8994->hubs.no_cache_class_w = true;
+                wm8994->hubs.no_cache_dac_hp_direct = true;
                 wm8994->fll_byp = true;
 
                 switch (wm8994->revision) {
diff --git a/sound/soc/codecs/wm_hubs.c b/sound/soc/codecs/wm_hubs.c
index f13f2886339c..15aed8b7d981 100644
--- a/sound/soc/codecs/wm_hubs.c
+++ b/sound/soc/codecs/wm_hubs.c
@@ -109,6 +109,42 @@ irqreturn_t wm_hubs_dcs_done(int irq, void *data)
 }
 EXPORT_SYMBOL_GPL(wm_hubs_dcs_done);
 
+static bool wm_hubs_dac_hp_direct(struct snd_soc_codec *codec)
+{
+        int reg;
+
+        /* If we're going via the mixer we'll need to do additional checks */
+        reg = snd_soc_read(codec, WM8993_OUTPUT_MIXER1);
+        if (!(reg & WM8993_DACL_TO_HPOUT1L)) {
+                if (reg & ~WM8993_DACL_TO_MIXOUTL) {
+                        dev_vdbg(codec->dev, "Analogue paths connected: %x\n",
+                                 reg & ~WM8993_DACL_TO_HPOUT1L);
+                        return false;
+                } else {
+                        dev_vdbg(codec->dev, "HPL connected to mixer\n");
+                        return false;
+                }
+        } else {
+                dev_vdbg(codec->dev, "HPL connected to DAC\n");
+        }
+
+        reg = snd_soc_read(codec, WM8993_OUTPUT_MIXER2);
+        if (!(reg & WM8993_DACR_TO_HPOUT1R)) {
+                if (reg & ~WM8993_DACR_TO_MIXOUTR) {
+                        dev_vdbg(codec->dev, "Analogue paths connected: %x\n",
+                                 reg & ~WM8993_DACR_TO_HPOUT1R);
+                        return false;
+                } else {
+                        dev_vdbg(codec->dev, "HPR connected to mixer\n");
+                        return false;
+                }
+        } else {
+                dev_vdbg(codec->dev, "HPR connected to DAC\n");
+        }
+
+        return true;
+}
+
 /*
  * Startup calibration of the DC servo
  */
@@ -129,10 +165,10 @@ static void calibrate_dc_servo(struct snd_soc_codec *codec)
 
         /* If we're using a digital only path and have a previously
          * callibrated DC servo offset stored then use that. */
-        if (hubs->class_w && hubs->class_w_dcs) {
+        if (wm_hubs_dac_hp_direct(codec) && hubs->dac_hp_direct_dcs) {
                 dev_dbg(codec->dev, "Using cached DC servo offset %x\n",
-                        hubs->class_w_dcs);
-                snd_soc_write(codec, dcs_reg, hubs->class_w_dcs);
+                        hubs->dac_hp_direct_dcs);
+                snd_soc_write(codec, dcs_reg, hubs->dac_hp_direct_dcs);
                 wait_for_dc_servo(codec,
                                   WM8993_DCS_TRIG_DAC_WR_0 |
                                   WM8993_DCS_TRIG_DAC_WR_1);
@@ -207,8 +243,8 @@ static void calibrate_dc_servo(struct snd_soc_codec *codec)
 
         /* Save the callibrated offset if we're in class W mode and
          * therefore don't have any analogue signal mixed in. */
-        if (hubs->class_w && !hubs->no_cache_class_w)
-                hubs->class_w_dcs = dcs_cfg;
+        if (wm_hubs_dac_hp_direct(codec) && !hubs->no_cache_dac_hp_direct)
+                hubs->dac_hp_direct_dcs = dcs_cfg;
 }
 
 /*
@@ -224,7 +260,7 @@ static int wm8993_put_dc_servo(struct snd_kcontrol *kcontrol,
         ret = snd_soc_put_volsw(kcontrol, ucontrol);
 
         /* Updating the analogue gains invalidates the DC servo cache */
-        hubs->class_w_dcs = 0;
+        hubs->dac_hp_direct_dcs = 0;
 
         /* If we're applying an offset correction then updating the
          * callibration would be likely to introduce further offsets. */
diff --git a/sound/soc/codecs/wm_hubs.h b/sound/soc/codecs/wm_hubs.h
index 5705276f4943..8bb9f1b51bf3 100644
--- a/sound/soc/codecs/wm_hubs.h
+++ b/sound/soc/codecs/wm_hubs.h
@@ -30,9 +30,8 @@ struct wm_hubs_data {
         int series_startup;
         int no_series_update;
 
-        bool no_cache_class_w;
-        bool class_w;
-        u16 class_w_dcs;
+        bool no_cache_dac_hp_direct;
+        u16 dac_hp_direct_dcs;
 
         bool lineout1_se;
         bool lineout1n_ena;