ALSA: hda: Make snd_hdac_display_power() void function

After the recent refactoring, snd_hdac_display_power() doesn't return
any error, hence it can be defined to return void.
This makes many error checks redundant and allows us to reduce them
gracefully.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/hda_component.h b/include/sound/hda_component.h
index 767c8d8..2ec31b3 100644
--- a/include/sound/hda_component.h
+++ b/include/sound/hda_component.h
@@ -12,8 +12,8 @@
 
 #ifdef CONFIG_SND_HDA_COMPONENT
 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable);
-int snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx,
-			   bool enable);
+void snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx,
+			    bool enable);
 int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid,
 			     int dev_id, int rate);
 int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid, int dev_id,
@@ -30,10 +30,9 @@
 {
 	return 0;
 }
-static inline int snd_hdac_display_power(struct hdac_bus *bus,
-					 unsigned int idx, bool enable)
+static inline void snd_hdac_display_power(struct hdac_bus *bus,
+					  unsigned int idx, bool enable)
 {
-	return 0;
 }
 static inline int snd_hdac_sync_audio_rate(struct hdac_device *codec,
 					   hda_nid_t nid, int dev_id, int rate)
diff --git a/sound/hda/hdac_component.c b/sound/hda/hdac_component.c
index dd76641..a6d37b9 100644
--- a/sound/hda/hdac_component.c
+++ b/sound/hda/hdac_component.c
@@ -62,10 +62,8 @@
  *
  * This function updates the power status, and calls the get_power() and
  * put_power() ops accordingly, toggling the codec wakeup, too.
- *
- * Returns zero for success or a negative error code.
  */
-int snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx, bool enable)
+void snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx, bool enable)
 {
 	struct drm_audio_component *acomp = bus->audio_component;
 
@@ -77,7 +75,7 @@
 		clear_bit(idx, &bus->display_power_status);
 
 	if (!acomp || !acomp->ops)
-		return 0;
+		return;
 
 	if (bus->display_power_status) {
 		if (!bus->display_power_active) {
@@ -94,8 +92,6 @@
 			bus->display_power_active = false;
 		}
 	}
-
-	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_display_power);
 
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 5399d01..e784130 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -2216,12 +2216,7 @@
 	 * this power. For other platforms, like Baytrail/Braswell, only the
 	 * display codec needs the power and it can be released after probe.
 	 */
-	err = display_power(chip, true);
-	if (err < 0) {
-		dev_err(chip->card->dev,
-			"Cannot turn on display power on i915\n");
-		goto i915_power_fail;
-	}
+	display_power(chip, true);
 
 	err = azx_first_init(chip);
 	if (err < 0)
@@ -2271,8 +2266,6 @@
 out_free:
 	if (err < 0 || !hda->need_i915_power)
 		display_power(chip, false);
-
-i915_power_fail:
 	if (err < 0)
 		hda->init_failed = 1;
 	complete_all(&hda->probe_wait);
diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c
index c3d551d..552ed19 100644
--- a/sound/soc/codecs/hdac_hdmi.c
+++ b/sound/soc/codecs/hdac_hdmi.c
@@ -2031,13 +2031,8 @@
 	 * Turned off in the runtime_suspend during the first explicit
 	 * pm_runtime_suspend call.
 	 */
-	ret = snd_hdac_display_power(hdev->bus, hdev->addr, true);
-	if (ret < 0) {
-		dev_err(&hdev->dev,
-			"Cannot turn on display power on i915 err: %d\n",
-			ret);
-		return ret;
-	}
+	snd_hdac_display_power(hdev->bus, hdev->addr, true);
+
 	ret = hdac_hdmi_parse_and_map_nid(hdev, &hdmi_dais, &num_dais);
 	if (ret < 0) {
 		dev_err(&hdev->dev,
@@ -2169,7 +2164,6 @@
 	struct hdac_device *hdev = dev_to_hdac_dev(dev);
 	struct hdac_bus *bus = hdev->bus;
 	struct hdac_ext_link *hlink = NULL;
-	int err;
 
 	dev_dbg(dev, "Enter: %s\n", __func__);
 
@@ -2195,11 +2189,9 @@
 
 	snd_hdac_ext_bus_link_put(bus, hlink);
 
-	err = snd_hdac_display_power(bus, hdev->addr, false);
-	if (err < 0)
-		dev_err(dev, "Cannot turn off display power on i915\n");
+	snd_hdac_display_power(bus, hdev->addr, false);
 
-	return err;
+	return 0;
 }
 
 static int hdac_hdmi_runtime_resume(struct device *dev)
@@ -2207,7 +2199,6 @@
 	struct hdac_device *hdev = dev_to_hdac_dev(dev);
 	struct hdac_bus *bus = hdev->bus;
 	struct hdac_ext_link *hlink = NULL;
-	int err;
 
 	dev_dbg(dev, "Enter: %s\n", __func__);
 
@@ -2223,11 +2214,7 @@
 
 	snd_hdac_ext_bus_link_get(bus, hlink);
 
-	err = snd_hdac_display_power(bus, hdev->addr, true);
-	if (err < 0) {
-		dev_err(dev, "Cannot turn on display power on i915\n");
-		return err;
-	}
+	snd_hdac_display_power(bus, hdev->addr, true);
 
 	hdac_hdmi_skl_enable_all_pins(hdev);
 	hdac_hdmi_skl_enable_dp12(hdev);
diff --git a/sound/soc/intel/skylake/skl.c b/sound/soc/intel/skylake/skl.c
index 64f8433..5c224a0 100644
--- a/sound/soc/intel/skylake/skl.c
+++ b/sound/soc/intel/skylake/skl.c
@@ -311,7 +311,7 @@
 	struct pci_dev *pci = to_pci_dev(dev);
 	struct hdac_bus *bus = pci_get_drvdata(pci);
 	struct skl *skl  = bus_to_skl(bus);
-	int ret = 0;
+	int ret;
 
 	/*
 	 * Do not suspend if streams which are marked ignore suspend are
@@ -333,14 +333,10 @@
 		skl->skl_sst->fw_loaded = false;
 	}
 
-	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI)) {
-		ret = snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
-		if (ret < 0)
-			dev_err(bus->dev,
-				"Cannot turn OFF display power on i915\n");
-	}
+	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI))
+		snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
 
-	return ret;
+	return 0;
 }
 
 static int skl_resume(struct device *dev)
@@ -352,14 +348,8 @@
 	int ret;
 
 	/* Turned OFF in HDMI codec driver after codec reconfiguration */
-	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI)) {
-		ret = snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
-		if (ret < 0) {
-			dev_err(bus->dev,
-				"Cannot turn on display power on i915\n");
-			return ret;
-		}
-	}
+	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI))
+		snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
 
 	/*
 	 * resume only when we are not in suspend active, otherwise need to
@@ -783,11 +773,9 @@
 	if (err < 0)
 		return err;
 
-	err = snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
-	if (err < 0)
-		dev_err(bus->dev, "Cannot turn on display power on i915\n");
+	snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
 
-	return err;
+	return 0;
 }
 
 static void skl_probe_work(struct work_struct *work)
@@ -837,14 +825,8 @@
 	list_for_each_entry(hlink, &bus->hlink_list, list)
 		snd_hdac_ext_bus_link_put(bus, hlink);
 
-	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI)) {
-		err = snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
-		if (err < 0) {
-			dev_err(bus->dev, "Cannot turn off display power on i915\n");
-			skl_machine_device_unregister(skl);
-			return;
-		}
-	}
+	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI))
+		snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
 
 	/* configure PM */
 	pm_runtime_put_noidle(bus->dev);
@@ -855,7 +837,7 @@
 
 out_err:
 	if (IS_ENABLED(CONFIG_SND_SOC_HDAC_HDMI))
-		err = snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
+		snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, false);
 }
 
 /*