This is a note to let you know that I've just added the patch titled ALSA: hda - Manage power well properly for resume to the 4.7-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-manage-power-well-properly-for-resume.patch and it can be found in the queue-4.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a52ff34e5ec61749c62c6618b76a9d6dbecee450 Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Thu, 4 Aug 2016 22:38:36 +0200 Subject: ALSA: hda - Manage power well properly for resume From: Takashi Iwai <tiwai@xxxxxxx> commit a52ff34e5ec61749c62c6618b76a9d6dbecee450 upstream. For SKL and later Intel chips, we control the power well per codec basis via link_power callback since the commit [03b135cebc47: ALSA: hda - remove dependency on i915 power well for SKL]. However, there are a few exceptional cases where the gfx registers are accessed from the audio driver: namely the wakeup override bit toggling at (both system and runtime) resume. This seems causing a kernel warning when accessed during the power well down (and likely resulting in the bogus register accesses). This patch puts the proper power up / down sequence around the resume code so that the wakeup bit is fiddled properly while the power is up. (The other callback, sync_audio_rate, is used only in the PCM callback, so it's guaranteed in the power-on.) Also, by this proper power up/down, the instantaneous flip of wakeup bit in the resume callback that was introduced by the commit [033ea349a7cd: ALSA: hda - Fix Skylake codec timeout] becomes superfluous, as snd_hdac_display_power() already does it. So we can clean it up together. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96214 Fixes: 03b135cebc47 ('ALSA: hda - remove dependency on i915 power well for SKL') Tested-by: Hans de Goede <hdegoede@xxxxxxxxxx> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/pci/hda/hda_intel.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -906,20 +906,23 @@ static int azx_resume(struct device *dev struct snd_card *card = dev_get_drvdata(dev); struct azx *chip; struct hda_intel *hda; + struct hdac_bus *bus; if (!card) return 0; chip = card->private_data; hda = container_of(chip, struct hda_intel, chip); + bus = azx_bus(chip); if (chip->disabled || hda->init_failed || !chip->running) return 0; - if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL - && hda->need_i915_power) { - snd_hdac_display_power(azx_bus(chip), true); - snd_hdac_i915_set_bclk(azx_bus(chip)); + if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) { + snd_hdac_display_power(bus, true); + if (hda->need_i915_power) + snd_hdac_i915_set_bclk(bus); } + if (chip->msi) if (pci_enable_msi(pci) < 0) chip->msi = 0; @@ -929,6 +932,11 @@ static int azx_resume(struct device *dev hda_intel_init_chip(chip, true); + /* power down again for link-controlled chips */ + if ((chip->driver_caps & AZX_DCAPS_I915_POWERWELL) && + !hda->need_i915_power) + snd_hdac_display_power(bus, false); + snd_power_change_state(card, SNDRV_CTL_POWER_D0); trace_azx_resume(chip); @@ -1008,6 +1016,7 @@ static int azx_runtime_resume(struct dev chip = card->private_data; hda = container_of(chip, struct hda_intel, chip); + bus = azx_bus(chip); if (chip->disabled || hda->init_failed) return 0; @@ -1015,15 +1024,9 @@ static int azx_runtime_resume(struct dev return 0; if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) { - bus = azx_bus(chip); - if (hda->need_i915_power) { - snd_hdac_display_power(bus, true); + snd_hdac_display_power(bus, true); + if (hda->need_i915_power) snd_hdac_i915_set_bclk(bus); - } else { - /* toggle codec wakeup bit for STATESTS read */ - snd_hdac_set_codec_wakeup(bus, true); - snd_hdac_set_codec_wakeup(bus, false); - } } /* Read STATESTS before controller reset */ @@ -1043,6 +1046,11 @@ static int azx_runtime_resume(struct dev azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) & ~STATESTS_INT_MASK); + /* power down again for link-controlled chips */ + if ((chip->driver_caps & AZX_DCAPS_I915_POWERWELL) && + !hda->need_i915_power) + snd_hdac_display_power(bus, false); + trace_azx_runtime_resume(chip); return 0; } Patches currently in stable-queue which might be from tiwai@xxxxxxx are queue-4.7/alsa-hda-manage-power-well-properly-for-resume.patch queue-4.7/alsa-usb-audio-add-quirk-for-elp-hd-usb-camera.patch queue-4.7/alsa-usb-audio-add-a-sample-rate-quirk-for-creative-live-cam-socialize-hd-vf0610.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html