On Wed, 15 Jul 2015 10:07:35 +0200, David Henningsson wrote:
On 2015-07-15 10:00, Takashi Iwai wrote:
On Wed, 15 Jul 2015 09:39:35 +0200, David Henningsson wrote:
When the controller is powered up but the HDMI codec is powered down on Skylake, the power well is turned off. When the codec is then powered up again, we need to poke the codec a little extra to make sure it wakes up. Otherwise we'll get sad "no response from codec" messages and broken audio.
Signed-off-by: David Henningsson david.henningsson@canonical.com Tested-by: Woodrow Shen woodrow.shen@canonical.com
It would good to have an ack from Intel on this patch, since they have better hardware knowledge than I.
Also I haven't really kept track of all recent reorganisation of the hda driver so I'm not totally sure how many kernels back (if any) that this applies to
sound/pci/hda/hda_intel.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index ca151b4..872e9a7 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -567,9 +567,17 @@ static int azx_position_check(struct azx *chip, struct azx_dev *azx_dev) /* Enable/disable i915 display power for the link */ static int azx_intel_link_power(struct azx *chip, bool enable) {
- int err; struct hdac_bus *bus = azx_bus(chip);
- return snd_hdac_display_power(bus, enable);
- err = snd_hdac_display_power(bus, enable);
- if (err < 0)
return err;- if (enable && (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)) {
snd_hdac_set_codec_wakeup(bus, true);snd_hdac_set_codec_wakeup(bus, false);- }
Wouldn't it be better to put in snd_hadc_display_power() itself?
I don't mind either way. Mengdong, do you have an opinion?
Oh, BTW, a clear difference is that my patch calls the wakeup only at the first power up. link_power() can be called multiple times, so there might behave differently, and needs the check whether it really works.
Takashi
--- a/sound/hda/hdac_i915.c +++ b/sound/hda/hdac_i915.c @@ -56,8 +56,11 @@ int snd_hdac_display_power(struct hdac_bus *bus, bool enable) enable ? "enable" : "disable");
if (enable) {
if (!bus->i915_power_refcount++)
if (!bus->i915_power_refcount++) { acomp->ops->get_power(acomp->dev);snd_hdac_set_codec_wakeup(bus, true);snd_hdac_set_codec_wakeup(bus, false);}Takashi
-- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic