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Message-ID: <ed9606a4-4be6-7403-6e32-1c045ac0bdf6@inbox.ru>
Date:   Wed, 21 Jun 2023 16:55:18 +0300
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Subject: Re: [PATCH 1/1] ASoC: codecs: max98090: Allow dsp_a mode
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To:     Mark Brown <broonie@kernel.org>
Cc:     alsa-devel@alsa-project.org, Liam Girdwood <lgirdwood@gmail.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Benjamin Mugnier <benjamin.mugnier@foss.st.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= <u.kleine-koenig@pengutronix.de>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        Charles Keepax <ckeepax@opensource.cirrus.com>,
        linux-kernel@vger.kernel.org
References: <20230621115328.156457-1-fido_max@inbox.ru>
 <3805dc65-113f-453a-90a9-2ae6204004ba@sirena.org.uk>
 <e6be75f6-054f-6c3b-00b4-a5e112bcefc3@inbox.ru>
 <b763d08e-f751-480c-96b6-339a53856768@sirena.org.uk>
From:   Maxim Kochetkov <fido_max@inbox.ru>
In-Reply-To: <b763d08e-f751-480c-96b6-339a53856768@sirena.org.uk>
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On 21.06.2023 16:18, Mark Brown wrote:
> On Wed, Jun 21, 2023 at 04:02:34PM +0300, Maxim Kochetkov wrote:
>> On 21.06.2023 15:26, Mark Brown wrote:
> 
>>> This is configuring DSP A identically to left justified mode, it looks
>>> like the format configuration needs at least some interlock with the TDM
>>> configuration.
> 
>> According to datasheet MAX98090 supports only DSP_A (L data MSB after FRM
>> LRC) TDM mode. Allowing this mode will let us proper configure CPU audio
>> node via DT. Actual TDM mode activation is performed in
>> max98090_set_tdm_slot() via M98090_REG_TDM_FORMAT/M98090_REG_TDM_CONTROL
>> registers.
> 
> I'm saying there should be some interlock between these two settings, if
> nothing else setting DSP A mode should force TDM mode with automatically
> configured slot sizes.

At this time there is no any interlock for TDM mode in MAX98090 driver. 
We can specify dai-tdm-slot-* properties in DT and .set_tdm_slot() will 
be called to setup TDM mode. And SND_SOC_DAIFMT cannot affect it. I 
checked other codecs drivers: most of them performs TDM setup this way. 
So why do we need such interlock right now?