ASoC: tlv320aic3x: Use regulator notifiers for optimizing the cache sync
authorJarkko Nikula <jhnikula@gmail.com>
Mon, 20 Sep 2010 07:39:13 +0000 (10:39 +0300)
committerLiam Girdwood <lrg@slimlogic.co.uk>
Mon, 20 Sep 2010 17:40:47 +0000 (18:40 +0100)
There is no need to reset the codec and perform cache sync if none of the
supply regulators were not disabled. Patch registers a notifier callback for
each supply and callback then sets a flag to indicate when cache sync is
required.

HW writes are also needless when codec bias is off so cache_only flag is set
independently of actual supply regulators state.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
sound/soc/codecs/tlv320aic3x.c

index 5f8a7c4045c2f3c38b76acb8d54a973d0b98325e..5356946fb6b295c971fd78ea6e0586ccccbb533b 100644 (file)
@@ -61,9 +61,18 @@ static const char *aic3x_supply_names[AIC3X_NUM_SUPPLIES] = {
        "DRVDD",        /* ADC Analog and Output Driver Voltage */
 };
 
+struct aic3x_priv;
+
+struct aic3x_disable_nb {
+       struct notifier_block nb;
+       struct aic3x_priv *aic3x;
+};
+
 /* codec private data */
 struct aic3x_priv {
+       struct snd_soc_codec *codec;
        struct regulator_bulk_data supplies[AIC3X_NUM_SUPPLIES];
+       struct aic3x_disable_nb disable_nb[AIC3X_NUM_SUPPLIES];
        enum snd_soc_control_type control_type;
        struct aic3x_setup_data *setup;
        void *control_data;
@@ -122,6 +131,8 @@ static int aic3x_read(struct snd_soc_codec *codec, unsigned int reg,
 {
        u8 *cache = codec->reg_cache;
 
+       if (codec->cache_only)
+               return -EINVAL;
        if (reg >= AIC3X_CACHEREGNUM)
                return -1;
 
@@ -1052,6 +1063,26 @@ static int aic3x_init_3007(struct snd_soc_codec *codec)
        return 0;
 }
 
+static int aic3x_regulator_event(struct notifier_block *nb,
+                                unsigned long event, void *data)
+{
+       struct aic3x_disable_nb *disable_nb =
+               container_of(nb, struct aic3x_disable_nb, nb);
+       struct aic3x_priv *aic3x = disable_nb->aic3x;
+
+       if (event & REGULATOR_EVENT_DISABLE) {
+               /*
+                * Put codec to reset and require cache sync as at least one
+                * of the supplies was disabled
+                */
+               if (aic3x->gpio_reset >= 0)
+                       gpio_set_value(aic3x->gpio_reset, 0);
+               aic3x->codec->cache_sync = 1;
+       }
+
+       return 0;
+}
+
 static int aic3x_set_power(struct snd_soc_codec *codec, int power)
 {
        struct aic3x_priv *aic3x = snd_soc_codec_get_drvdata(codec);
@@ -1064,6 +1095,13 @@ static int aic3x_set_power(struct snd_soc_codec *codec, int power)
                if (ret)
                        goto out;
                aic3x->power = 1;
+               /*
+                * Reset release and cache sync is necessary only if some
+                * supply was off or if there were cached writes
+                */
+               if (!codec->cache_sync)
+                       goto out;
+
                if (aic3x->gpio_reset >= 0) {
                        udelay(1);
                        gpio_set_value(aic3x->gpio_reset, 1);
@@ -1078,8 +1116,8 @@ static int aic3x_set_power(struct snd_soc_codec *codec, int power)
                codec->cache_sync = 0;
        } else {
                aic3x->power = 0;
-               if (aic3x->gpio_reset >= 0)
-                       gpio_set_value(aic3x->gpio_reset, 0);
+               /* HW writes are needless when bias is off */
+               codec->cache_only = 1;
                ret = regulator_bulk_disable(ARRAY_SIZE(aic3x->supplies),
                                             aic3x->supplies);
        }
@@ -1315,6 +1353,7 @@ static int aic3x_probe(struct snd_soc_codec *codec)
        int ret, i;
 
        codec->control_data = aic3x->control_data;
+       aic3x->codec = codec;
 
        ret = snd_soc_codec_set_cache_io(codec, 8, 8, aic3x->control_type);
        if (ret != 0) {
@@ -1338,6 +1377,18 @@ static int aic3x_probe(struct snd_soc_codec *codec)
                dev_err(codec->dev, "Failed to request supplies: %d\n", ret);
                goto err_get;
        }
+       for (i = 0; i < ARRAY_SIZE(aic3x->supplies); i++) {
+               aic3x->disable_nb[i].nb.notifier_call = aic3x_regulator_event;
+               aic3x->disable_nb[i].aic3x = aic3x;
+               ret = regulator_register_notifier(aic3x->supplies[i].consumer,
+                                                 &aic3x->disable_nb[i].nb);
+               if (ret) {
+                       dev_err(codec->dev,
+                               "Failed to request regulator notifier: %d\n",
+                                ret);
+                       goto err_notif;
+               }
+       }
 
        ret = regulator_bulk_enable(ARRAY_SIZE(aic3x->supplies),
                                    aic3x->supplies);
@@ -1372,6 +1423,10 @@ static int aic3x_probe(struct snd_soc_codec *codec)
        return 0;
 
 err_enable:
+err_notif:
+       while (i--)
+               regulator_unregister_notifier(aic3x->supplies[i].consumer,
+                                             &aic3x->disable_nb[i].nb);
        regulator_bulk_free(ARRAY_SIZE(aic3x->supplies), aic3x->supplies);
 err_get:
        if (aic3x->gpio_reset >= 0)
@@ -1384,6 +1439,7 @@ err_gpio:
 static int aic3x_remove(struct snd_soc_codec *codec)
 {
        struct aic3x_priv *aic3x = snd_soc_codec_get_drvdata(codec);
+       int i;
 
        aic3x_set_bias_level(codec, SND_SOC_BIAS_OFF);
        if (aic3x->gpio_reset >= 0) {
@@ -1391,6 +1447,9 @@ static int aic3x_remove(struct snd_soc_codec *codec)
                gpio_free(aic3x->gpio_reset);
        }
        regulator_bulk_disable(ARRAY_SIZE(aic3x->supplies), aic3x->supplies);
+       for (i = 0; i < ARRAY_SIZE(aic3x->supplies); i++)
+               regulator_unregister_notifier(aic3x->supplies[i].consumer,
+                                             &aic3x->disable_nb[i].nb);
        regulator_bulk_free(ARRAY_SIZE(aic3x->supplies), aic3x->supplies);
 
        return 0;