Patch "ALSA: hda - Really restrict i915 notifier to HSW+" has been added to the 4.5-stable tree

This is a note to let you know that I've just added the patch titled

ALSA: hda - Really restrict i915 notifier to HSW+

to the 4.5-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
alsa-hda-really-restrict-i915-notifier-to-hsw.patch
and it can be found in the queue-4.5 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Takashi Iwai <[email protected]>
Date: Fri, 18 Mar 2016 15:10:08 +0100
Subject: ALSA: hda - Really restrict i915 notifier to HSW+
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From: Takashi Iwai <[email protected]>

commit 691be973c0621255abb31572a98e35c57be70212 upstream.

The commit [b62232d429fa: ALSA: hda - Limit i915 HDMI binding only for HSW and later] tried to limit the usage of i915 audio notifier to the recent Intel models and switch to the old method on pre-Haswell models. However, it assumed that the i915 component binding hasn't been done on such models, and the assumption was wrong: namely, Baytrail had already the i915 component binding due to powerwell control. Thus, the workaround wasn't applied to Baytrail.

For fixing this properly, this patch introduces a new flag indicating the usage of audio notifier and codec_has_acomp() refers to this flag instead of checking the existence of audio component.

---
 sound/pci/hda/patch_hdmi.c |   24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

@@ -152,13 +152,17 @@ struct hdmi_spec {
 	struct hda_pcm_stream pcm_playback;
 
 	/* i915/powerwell (Haswell+/Valleyview+) specific */
+	bool use_acomp_notifier; /* use i915 eld_notify callback for hotplug */
 	struct i915_audio_component_audio_ops i915_audio_ops;
 	bool i915_bound; /* was i915 bound in this driver? */
 };
 
 #ifdef CONFIG_SND_HDA_I915
-#define codec_has_acomp(codec) \
-	((codec)->bus->core.audio_component != NULL)
+static inline bool codec_has_acomp(struct hda_codec *codec)
+{
+	struct hdmi_spec *spec = codec->spec;
+	return spec->use_acomp_notifier;
+}
 #else
 #define codec_has_acomp(codec)	false
 #endif

@@ -2461,12 +2465,18 @@ static int patch_generic_hdmi(struct hda
 	codec->spec = spec;
 	hdmi_array_init(spec, 4);
 
+#ifdef CONFIG_SND_HDA_I915
 	/* Try to bind with i915 for Intel HSW+ codecs (if not done yet) */
-	if (!codec_has_acomp(codec) &&
-	    (codec->core.vendor_id >> 16) == 0x8086 &&
-	    is_haswell_plus(codec))
-		if (!snd_hdac_i915_init(&codec->bus->core))
-			spec->i915_bound = true;
+	if ((codec->core.vendor_id >> 16) == 0x8086 &&
+	    is_haswell_plus(codec)) {
+		if (!codec->bus->core.audio_component)
+			if (!snd_hdac_i915_init(&codec->bus->core))
+				spec->i915_bound = true;
+		/* use i915 audio component notifier for hotplug */
+		if (codec->bus->core.audio_component)
+			spec->use_acomp_notifier = true;
+	}
+#endif
 
 	if (is_haswell_plus(codec)) {
 		intel_haswell_enable_all_pins(codec, true);

Patches currently in stable-queue which might be from [email protected] are

queue-4.5/alsa-hda-apply-reboot-d3-fix-for-cx20724-codec-too.patch queue-4.5/alsa-intel8x0-add-clock-quirk-entry-for-ad1981b-on-ibm-thinkpad-x41.patch queue-4.5/alsa-hda-add-new-gpu-codec-id-0x10de0082-to-snd-hda.patch queue-4.5/alsa-hda-limit-i915-hdmi-binding-only-for-hsw-and-later.patch queue-4.5/alsa-hda-fix-unexpected-resume-through-regmap-code-path.patch queue-4.5/alsa-hda-fix-missing-eld-update-at-unplugging.patch queue-4.5/alsa-hda-really-restrict-i915-notifier-to-hsw.patch queue-4.5/alsa-usb-audio-add-microsoft-hd-5001-to-quirks.patch queue-4.5/alsa-hda-workaround-for-unbalanced-i915-power-refcount-by-concurrent-probe.patch queue-4.5/alsa-usb-audio-fix-null-dereference-in-create_fixed_stream_quirk.patch queue-4.5/alsa-hda-fix-spurious-kernel-warning-on-baytrail-hdmi.patch queue-4.5/alsa-usb-audio-minor-code-cleanup-in-create_fixed_stream_quirk.patch queue-4.5/alsa-pcm-avoid-bug-string-for-warnings-again.patch queue-4.5/alsa-usb-audio-fix-double-free-in-error-paths-after-snd_usb_add_audio_stream-call.patch queue-4.5/alsa-hda-fix-unconditional-gpio-toggle-via-automute.patch queue-4.5/alsa-hda-don-t-handle-eld-notify-from-invalid-port.patch queue-4.5/alsa-usb-audio-add-sanity-checks-for-endpoint-accesses.patch queue-4.5/alsa-hda-fix-the-mic-mute-button-and-led-problem-for-a-lenovo-aio.patch queue-4.5/alsa-hda-fix-forgotten-hdmi-monitor_present-update.patch