Re: [PATCH 0/3] ASoC: grace time for DPCM cleanup

From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To: Jerome Brunet <jbrunet@baylibre.com>
Cc: "Amadeusz Sławiński" <amadeuszx.slawinski@linux.intel.com>,
	"Alexandre Belloni" <alexandre.belloni@bootlin.com>,
	"Alper Nebi Yasak" <alpernebiyasak@gmail.com>,
	"AngeloGioacchino Del Regno"
	<angelogioacchino.delregno@collabora.com>,
	"Banajit Goswami" <bgoswami@quicinc.com>,
	"Bard Liao" <yung-chuan.liao@linux.intel.com>,
	"Brent Lu" <brent.lu@intel.com>,
	"Cezary Rojewski" <cezary.rojewski@intel.com>,
	"Charles Keepax" <ckeepax@opensource.cirrus.com>,
	"Claudiu Beznea" <claudiu.beznea@tuxon.dev>,
	"Cristian Ciocaltea" <cristian.ciocaltea@collabora.com>,
	"Daniel Baluta" <daniel.baluta@nxp.com>,
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	"Srinivas Kandagatla" <srinivas.kandagatla@linaro.org>,
	"Sylwester Nawrocki" <s.nawrocki@samsung.com>,
	"Takashi Iwai" <tiwai@suse.com>, "Vinod Koul" <vkoul@kernel.org>,
	"Xiubo Li" <Xiubo.Lee@gmail.com>,
	alsa-devel@alsa-project.org, imx@lists.linux.dev,
	linux-doc@vger.kernel.org, linux-sound@vger.kernel.org
Subject: Re: [PATCH 0/3] ASoC: grace time for DPCM cleanup
Date: Mon, 13 May 2024 23:42:59 +0000	[thread overview]
Message-ID: <87h6f1jn25.wl-kuninori.morimoto.gx@renesas.com> (raw)
In-Reply-To: <1jseymyxa6.fsf@starbuckisacylon.baylibre.com>

Hi Jerome

Thank you for your reply

> However, I'm a bit confused. If it is handled automatically by the CPUs
> and Codecs settings, does it mean dpcm_playback/capture flags are
> no-ops from now on ?

Yes.
dpcm_playback/capture flag itself will be exist for a while, but it will be
removed soon (v6.11 ? v6.12 ? not yet fixed).

Some driver might is using dpcm_xxx flag as limitation of direction. For
example HW can use both playback/capture, but driver want to use playback
only, in this case, driver might have dpcm_playback flag only.

In this case, driver authoer need to update to use playback_only flag
instead. [1/3] patch will indicate warning about it, for a while.

> Should I update my card drivers to ditch those flags completely ?

If the driver is using dpcm_xxx flag as limitation of direction,
driver author need to update to use xxx_only flag.
If the driver have no such flag miss, I will remove all dpcm_xxx flags
when end of its support.
Of course we can avoid extra problem if each driver author remove/update
it by themself, instead of me ;P

> May I still disable a direction on a link from the card driver, like in
> the case I described above, when a TDM link has no slots for a direction ?

For example, in case of CPU can handle both playback/capture, and Codec
handles playback only, it will be playback only automatically, no Card
settings is needed.

If both CPU/Codec can handle playback/capture, but you want to enable
playback only, you can use playback_only flag.

Is it help you ?

Thank you for your help !!

Best regards
---
Renesas Electronics
Ph.D. Kuninori Morimoto