Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <e20884d2-5d30-9519-d070-8e2ac07f2171@linaro.org>
Date:   Mon, 12 Dec 2022 09:40:46 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.5.1
Subject: Re: [PATCH v3 10/12] dt-bindings: mediatek: mt8188: add audio afe
 document
To:     =?UTF-8?B?VHJldm9yIFd1ICjlkLPmlofoia8p?= <Trevor.Wu@mediatek.com>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "broonie@kernel.org" <broonie@kernel.org>,
        "p.zabel@pengutronix.de" <p.zabel@pengutronix.de>,
        "tiwai@suse.com" <tiwai@suse.com>,
        "lgirdwood@gmail.com" <lgirdwood@gmail.com>,
        "krzysztof.kozlowski+dt@linaro.org" 
        <krzysztof.kozlowski+dt@linaro.org>,
        "matthias.bgg@gmail.com" <matthias.bgg@gmail.com>,
        "perex@perex.cz" <perex@perex.cz>
Cc:     "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-mediatek@lists.infradead.org" 
        <linux-mediatek@lists.infradead.org>,
        "angelogioacchino.delregno@collabora.com" 
        <angelogioacchino.delregno@collabora.com>,
        "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
        Project_Global_Chrome_Upstream_Group 
        <Project_Global_Chrome_Upstream_Group@mediatek.com>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
References: <20221208033148.21866-1-trevor.wu@mediatek.com>
 <20221208033148.21866-11-trevor.wu@mediatek.com>
 <d7d9f3c7-b3e3-1e13-a80f-c7bf7b38a5b1@linaro.org>
 <45b4b287dfd57b99e0ba5675bf99194f6d84d9da.camel@mediatek.com>
 <fb34e446-2904-a357-e54b-3e82a2b0745c@linaro.org>
 <e08fab2a694313abc12e0f8303de3e2e704b388c.camel@mediatek.com>
Content-Language: en-US
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <e08fab2a694313abc12e0f8303de3e2e704b388c.camel@mediatek.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 12/12/2022 03:43, Trevor Wu (吳文良) wrote:
>>>
>>>>> +    uniqueItems: true
>>>>> +    items:
>>>>> +      minimum: 0
>>>>> +      maximum: 15
>>>>> +
>>>>> +  "^mediatek,etdm-in[1-2]-mclk-always-on-rate-hz$":
>>>>> +    description: Specify etdm in mclk output rate for always
>>>>> on
>>>>> case.
>>>>
>>>> How is it different than assigned-clock-rates?
>>>>
>>>
>>> This includes clock enabling at init stage.
>>
>> assigned-clock-rates are also at init stage. I asked what is
>> different.
>>
> 
> If the property is used, there are three parts included in dai driver
> probe function.
> 
> 1. set clock parent (which APLL)
> 2. set clock rate (MCLK rate)
> 3. enable clock (MCLK On)
> 
> The first two parts can be done by existing dts clock properties, but
> the last one can't.
> When MCLK should be enabled at boot time and kept on, this property is used. That's why I say the property is designed for always-on case.

Heh, so the "always on case" means this property enables clock? How is
this even DT property? That's not how clocks should be kept enabled. You
need proper clock provider and consumer.


Best regards,
Krzysztof