linux-kernel - Re: [PATCH v4 1/3] drm/bridge/synopsys: dsi: stop clobbering drvdata

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Message-ID: <f1bd1246-98d1-3d48-ae9f-657eff39d3a2@rock-chips.com>
Date:   Wed, 6 Dec 2017 15:16:28 +0800
From:   Nickey Yang <nickey.yang@...k-chips.com>
To:     Brian Norris <briannorris@...omium.org>
Cc:     Philippe CORNU <philippe.cornu@...com>,
        "robh+dt@...nel.org" <robh+dt@...nel.org>,
        "heiko@...ech.de" <heiko@...ech.de>,
        "mark.rutland@....com" <mark.rutland@....com>,
        "airlied@...ux.ie" <airlied@...ux.ie>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "linux-rockchip@...ts.infradead.org" 
        <linux-rockchip@...ts.infradead.org>,
        "laurent.pinchart@...asonboard.com" 
        <laurent.pinchart@...asonboard.com>,
        "seanpaul@...omium.org" <seanpaul@...omium.org>,
        "mka@...omium.org" <mka@...omium.org>,
        "hoegsberg@...il.com" <hoegsberg@...il.com>,
        "architt@...eaurora.org" <architt@...eaurora.org>,
        Yannick FERTRE <yannick.fertre@...com>,
        "hl@...k-chips.com" <hl@...k-chips.com>,
        "zyw@...k-chips.com" <zyw@...k-chips.com>,
        "xbl@...k-chips.com" <xbl@...k-chips.com>
Subject: Re: [PATCH v4 1/3] drm/bridge/synopsys: dsi: stop clobbering drvdata

Hi Brian,


On 2017年12月06日 02:56, Brian Norris wrote:
> Hi Nickey,
>
> On Tue, Dec 05, 2017 at 05:14:11PM +0800, Nickey Yang wrote:
>> On 2017年12月01日 18:07, Philippe CORNU wrote:
>>> On 12/01/2017 10:11 AM, Nickey Yang wrote:
>>>> On 2017年12月01日 16:32, Philippe CORNU wrote:
>>>>> I am sorry to say that but you can not add my "Acked-by" to this patch
>>>>> because this code is different from the "original" one from Brian (which
>>>>> got my "Acked-by").
>>>> I'm sorry I didn't think much about it, Thank you for correcting me.
>>>>> Sometimes it is not an issue because differences are not important but
>>>>> in this particular case, the code is really different: you have remove
>>>>> platform_set_drvdata() & platform_get_drvdata() in the stm part.
>>>>>
>>>>> Could you please go back to the original code or propose me an updated
>>>>> version of this code.
>>>> Could you help update new version of this code(stm part) and then test on
>>>> stm platform?
>>> I think you can simply goes back to the original version from Brian (see
>>> the discussion thread in https://patchwork.kernel.org/patch/10078493/)
>>> unless you have specific/good reasons for modifying the code as you did.
>> mmm,I'm sorry, I feel a little puzzled. Do you means we should abandon
>> Brian's patch (https://patchwork.kernel.org/patch/10078493/)?
>> I think we need to adjust stm part because  dw_mipi_dsi_stm.c calls
>> bridge's drivers if we want merge Brian's patch.
> It's really simple. Your code is different from the patch I sent, and in
> a way that Philippe did not like. I'll highlight it again below:
>
>>>>>> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>>>> index e5b6310..80f9950 100644
>>>>>> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>>>> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>>>> @@ -66,6 +66,7 @@ enum dsi_color {
>>>>>>     struct dw_mipi_dsi_stm {
>>>>>>     	void __iomem *base;
>>>>>>     	struct clk *pllref_clk;
>>>>>> +	struct dw_mipi_dsi *dmd;
>>>>>>     };
>>>>>>     static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 val)
>>>>>> @@ -318,10 +319,11 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>>>>>>     	dw_mipi_dsi_stm_plat_data.base = dsi->base;
>>>>>>     	dw_mipi_dsi_stm_plat_data.priv_data = dsi;
>>>>>> -	ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>>>>>> -	if (ret) {
>>>>>> +	dsi->dmd = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>>>>>> +	if (IS_ERR(dsi->dmd)) {
>>>>>>     		DRM_ERROR("Failed to initialize mipi dsi host\n");
>>>>>>     		clk_disable_unprepare(dsi->pllref_clk);
>>>>>> +		return PTR_ERR(dsi->dmd);
>>>>>>     	}
>>>>>>     	return ret;
>>>>>> @@ -332,7 +334,7 @@ static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
>>>>>>     	struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
>>>>>>     	clk_disable_unprepare(dsi->pllref_clk);
>>>>>> -	dw_mipi_dsi_remove(pdev);
>>>>>> +	dw_mipi_dsi_remove(dsi->dmd);
>>>>>>     	return 0;
>>>>>>     }
>   
> Above is your diff for dw_mipi_dsi-stm.c. Particularly, notice that
> remove() is directly referencing the static dw_mipi_dsi_stm_plat_data
> struct.
>
> If you look back at my patch [1] you'll see that you're missing hunks
> like this:
>
Thank you for pointing out my mistake.
I will fix this in next version.

Nickey.
>   static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
>   {
> -	struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
> +	struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
>   
>   	clk_disable_unprepare(dsi->pllref_clk);
> [...]
>
> Brian
>
> [1] https://patchwork.kernel.org/patch/10078493/
>
>
>