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: <6c3422e8-4e2e-ba3a-4f30-d24308ef7c2a@baylibre.com>
Date:   Thu, 20 Jul 2023 14:07:04 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.13.0
Subject: Re: [PATCH v3,3/3] drm/mediatek: dp: Add the audio divider to
 mtk_dp_data struct
Content-Language: en-US
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Shuijing Li <shuijing.li@mediatek.com>,
        chunkuang.hu@kernel.org, p.zabel@pengutronix.de, airlied@gmail.com,
        daniel@ffwll.ch, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        matthias.bgg@gmail.com, jitao.shi@mediatek.com
Cc:     dri-devel@lists.freedesktop.org,
        linux-mediatek@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Project_Global_Chrome_Upstream_Group@mediatek.com
References: <20230720082604.18618-1-shuijing.li@mediatek.com>
 <20230720082604.18618-4-shuijing.li@mediatek.com>
 <44cc9cc5-7dce-f7a2-f077-b62d7851ee12@baylibre.com>
 <65da6005-3c07-a7ea-6b63-db45c8915ae8@collabora.com>
From:   Alexandre Mergnat <amergnat@baylibre.com>
In-Reply-To: <65da6005-3c07-a7ea-6b63-db45c8915ae8@collabora.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk


On 20/07/2023 13:54, AngeloGioacchino Del Regno wrote:
> Il 20/07/23 12:14, Alexandre Mergnat ha scritto:
>>
>>
>> On 20/07/2023 10:26, Shuijing Li wrote:
>>> Due to the difference of HW, different dividers need to be set.
>>>
>>> Signed-off-by: Shuijing Li <shuijing.li@mediatek.com>
>>> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
>>> ---
>>> Changes in v3:
>>> Separate these two things into two different patches.
>>> per suggestion from the previous thread:
>>> https://lore.kernel.org/lkml/e2ad22bcba31797f38a12a488d4246a01bf0cb2e.camel@mediatek.com/
>>> Changes in v2:
>>> - change the variables' name to be more descriptive
>>> - add a comment that describes the function of 
>>> mtk_dp_audio_sample_arrange
>>> - reduce indentation by doing the inverse check
>>> - add a definition of some bits
>>> - add support for mediatek, mt8188-edp-tx
>>> per suggestion from the previous thread:
>>> https://lore.kernel.org/lkml/ac0fcec9-a2fe-06cc-c727-189ef7babe9c@collabora.com/
>>> ---
>>>   drivers/gpu/drm/mediatek/mtk_dp.c     | 7 ++++++-
>>>   drivers/gpu/drm/mediatek/mtk_dp_reg.h | 1 +
>>>   2 files changed, 7 insertions(+), 1 deletion(-)
>>>
...
>>> b/drivers/gpu/drm/mediatek/mtk_dp_reg.h
>>> index f38d6ff12afe..6d7f0405867e 100644
>>> --- a/drivers/gpu/drm/mediatek/mtk_dp_reg.h
>>> +++ b/drivers/gpu/drm/mediatek/mtk_dp_reg.h
>>> @@ -162,6 +162,7 @@
>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_MUL_2    (1 << 8)
>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_MUL_4    (2 << 8)
>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_MUL_8    (3 << 8)
>>> +#define MT8188_AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_DIV_2    (4 << 8)
>>
>> IMO, it's a bit weird to have SoC specific define in the generic header.
>> Are you sure this bit is only available for MT8188 ?
>>
> 
> Eh, the P0_DIV2 bit is 5<<8 for MT8195, while for 8188 it's 4<<8, 
> clearly :-)
> 

Ok then, to avoid this kind of issue for other SoCs in the future, is 
that make sense for you to do a SoC specific header file beside the 
generic one?

>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_DIV_2    (5 << 8)
>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_DIV_4    (6 << 8)
>>>   #define AUDIO_M_CODE_MULT_DIV_SEL_DP_ENC0_P0_DIV_8    (7 << 8)
>>
>> Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
>>
> 
> 

-- 
Regards,
Alexandre