ACK: [PATCH 1/1][SRU][I/U] ALSA: hda/cs8409: Set PMSG_ON earlier inside cs8409 driver

[Kleber Souza]

On 14.12.21 14:38, Chris Chiu wrote:
> From: Stefan Binding <sbinding at opensource.cirrus.com>
>
> BugLink: https://bugs.launchpad.net/bugs/1954773
>
> For cs8409, it is required to run Jack Detect on resume.
> Jack Detect on cs8409+cs42l42 requires an interrupt from
> cs42l42 to be sent to cs8409 which is propogated to the driver
> via an unsolicited event.
> However, the hda_codec drops unsolicited events if the power_state
> is not set to PMSG_ON. Which is set at the end of the resume call.
> This means there is a race condition between setting power_state
> to PMSG_ON and receiving the interrupt.
> To solve this, we can add an API to set the power_state earlier
> and call that before we start Jack Detect.
> This does not cause issues, since we know inside our driver that
> we are already initialized, and ready to handle the unsolicited
> events.
>
> Signed-off-by: Stefan Binding <sbinding at opensource.cirrus.com>
> Signed-off-by: Vitaly Rodionov <vitalyr at opensource.cirrus.com>
> Cc: <stable at vger.kernel.org> # v5.15+
> Link: https://lore.kernel.org/r/20211128115558.71683-1-vitalyr@opensource.cirrus.com
> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> (cherry picked from commit 65cc4ad62a9ed47c0b4fcd7af667d97d7c29f19d)
> Signed-off-by: Chris Chiu <chris.chiu at canonical.com>

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>

Thanks

> ---
>   sound/pci/hda/hda_local.h    | 9 +++++++++
>   sound/pci/hda/patch_cs8409.c | 5 +++++
>   2 files changed, 14 insertions(+)
>
> diff --git a/sound/pci/hda/hda_local.h b/sound/pci/hda/hda_local.h
> index ea8ab8b43337..d22c96eb2f8f 100644
> --- a/sound/pci/hda/hda_local.h
> +++ b/sound/pci/hda/hda_local.h
> @@ -438,6 +438,15 @@ int snd_hda_codec_set_pin_target(struct hda_codec *codec, hda_nid_t nid,
>   #define for_each_hda_codec_node(nid, codec) \
>   	for ((nid) = (codec)->core.start_nid; (nid) < (codec)->core.end_nid; (nid)++)
>   
> +/* Set the codec power_state flag to indicate to allow unsol event handling;
> + * see hda_codec_unsol_event() in hda_bind.c.  Calling this might confuse the
> + * state tracking, so use with care.
> + */
> +static inline void snd_hda_codec_allow_unsol_events(struct hda_codec *codec)
> +{
> +	codec->core.dev.power.power_state = PMSG_ON;
> +}
> +
>   /*
>    * get widget capabilities
>    */
> diff --git a/sound/pci/hda/patch_cs8409.c b/sound/pci/hda/patch_cs8409.c
> index 31ff11ab868e..039b9f2f8e94 100644
> --- a/sound/pci/hda/patch_cs8409.c
> +++ b/sound/pci/hda/patch_cs8409.c
> @@ -750,6 +750,11 @@ static void cs42l42_resume(struct sub_codec *cs42l42)
>   	if (cs42l42->full_scale_vol)
>   		cs8409_i2c_write(cs42l42, 0x2001, 0x01);
>   
> +	/* we have to explicitly allow unsol event handling even during the
> +	 * resume phase so that the jack event is processed properly
> +	 */
> +	snd_hda_codec_allow_unsol_events(cs42l42->codec);
> +
>   	cs42l42_enable_jack_detect(cs42l42);
>   }
>