Hi Takashi,
-----Original Message----- From: Takashi Iwai [mailto:tiwai@suse.de] Sent: Tuesday, April 16, 2019 6:24 PM To: Yang, Libin libin.yang@intel.com Cc: alsa-devel@alsa-project.org; broonie@kernel.org; pierre- louis.bossart@linux.intel.com Subject: Re: [alsa-devel] [PATCH v2] ASoC: codec: hdac_hdmi add device_link to card device
On Sat, 13 Apr 2019 15:18:12 +0200, libin.yang@intel.com wrote:
From: Libin Yang libin.yang@intel.com
In resume from S3, HDAC HDMI codec driver dapm event callback may be operated before HDMI codec driver turns on the display audio power domain because of the contest between display driver and hdmi codec
driver.
This patch adds the device_link between soc card device (consumer) and hdmi codec device (supplier) to make sure the sequence is always correct.
Signed-off-by: Libin Yang libin.yang@intel.com
Reviewed-by: Takashi Iwai tiwai@suse.de
Thanks for the review.
Is it an issue that has been present for older released kernels? If so, it deserves for Cc-to-stable.
It is for all released kernels, and the rates of reproduce are different. It's graphics driver related.
Regards, Libin
thanks,
Takashi
sound/soc/codecs/hdac_hdmi.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c index 5eeb0fe..4de1fbf 100644 --- a/sound/soc/codecs/hdac_hdmi.c +++ b/sound/soc/codecs/hdac_hdmi.c @@ -1855,6 +1855,17 @@ static int hdmi_codec_probe(struct
snd_soc_component *component)
hdmi->card = dapm->card->snd_card;
/*
* Setup a device_link between card device and HDMI codec device.* The card device is the consumer and the HDMI codec device is* the supplier. With this setting, we can make sure that the audio* domain in display power will be always turned on before operating* on the HDMI audio codec registers.* Let's use the flag DL_FLAG_AUTOREMOVE_CONSUMER. This canmake
* sure the device link is freed when the machine driver is removed.*/- device_link_add(component->card->dev, &hdev->dev,
DL_FLAG_RPM_ACTIVE |
DL_FLAG_AUTOREMOVE_CONSUMER);- /*
*/
- hdac_device core already sets the state to active and calls
- get_noresume. So enable runtime and set the device to suspend.
-- 2.7.4