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Subject: Re: [PATCH 2/2] ASoC: tlv320adcx140: Wake up codec before accessing
 register
From:   Dan Murphy <dmurphy@ti.com>
To:     Camel Guo <camel.guo@axis.com>, <lgirdwood@gmail.com>,
        <broonie@kernel.org>, <tiwai@suse.com>
CC:     <alsa-devel@alsa-project.org>, <linux-kernel@vger.kernel.org>,
        <kernel@axis.com>, Camel Guo <camelg@axis.com>
References: <20200908083521.14105-1-camel.guo@axis.com>
 <20200908083521.14105-2-camel.guo@axis.com>
 <89f8cce0-2407-15f5-a8e5-0aa17a2eb2c4@ti.com>
Message-ID: <8160bf81-a72d-2db0-0767-79b0509ff143@ti.com>
Date:   Tue, 8 Sep 2020 09:58:55 -0500
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Camel

On 9/8/20 6:49 AM, Dan Murphy wrote:
> Camel
>
> On 9/8/20 3:35 AM, Camel Guo wrote:
>> From: Camel Guo <camelg@axis.com>
>>
>> According to its datasheet, after reset this codec goes into sleep
>> mode. In this mode, any register accessing should be avoided except for
>> exiting sleep mode. Hence this commit moves SLEEP_CFG access before any
>> register accessing.
>
> This is interesting because our HW team suggested putting the device 
> into sleep mode when doing register writes/reads because they were 
> finding abnormalities in the register settings when the device is active.
>
> I have a local patch that changes this as well that the HW team 
> requested.


OK I have clarification on this now.  Their original request was 
incorrect they indicate the BIAS, ADC and PLLs be powered down during 
writes and reads.


>
> Mark
>
> Let me run this by the HW team first before applying this patch.

Mark

Acked-by: Dan Murphy <dmurphy@ti.com>


>
> Dan
>