Hi Pierre,
-----Original Message----- From: Pierre-Louis Bossart [mailto:pierre-louis.bossart@linux.intel.com] Sent: Friday, April 12, 2019 11:00 AM To: Yang, Libin libin.yang@intel.com; alsa-devel@alsa-project.org; tiwai@suse.de; broonie@kernel.org Subject: Re: [alsa-devel] [PATCH] ASoC: codec: hdac_hdmi add device_link to card device
On 4/11/19 9:40 PM, 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
sound/soc/codecs/hdac_hdmi.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c index 5eeb0fe..8bb883e 100644 --- a/sound/soc/codecs/hdac_hdmi.c +++ b/sound/soc/codecs/hdac_hdmi.c @@ -1855,6 +1855,15 @@ 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.*/- device_link_add(component->card->dev, &hdev->dev,
DL_FLAG_RPM_ACTIVE |
DL_FLAG_AUTOREMOVE_CONSUMER);Should device_link_free() be added to hdmi_codec_remove then?
As Takashi suggested, I add the DL_FLAG_AUTOREMOVE_CONSUMER flag. This will make sure the link will be freed when machine driver are removed. And as machine driver depends on the hdac_hdmi module, when hdmi_codec_remove() is called, the link is freed already.
Regards, Libin
Thanks!