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Message-ID: <59ea53d6-2856-fedd-3a5e-6ad5bdcd4a20@gmail.com>
Date:   Thu, 2 Jun 2022 10:05:20 +0800
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Subject: Re: [PATCH v3] drm/v3d/v3d_drv: Fix PM disable depth imbalance
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To:     Thierry Reding <thierry.reding@gmail.com>
Cc:     Emma Anholt <emma@anholt.net>, David Airlie <airlied@linux.ie>,
        Eric Anholt <eric@anholt.net>, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
References: <20220601122050.1822-1-linmq006@gmail.com>
 <YpdpCWW9+igsVydr@phenom.ffwll.local>
 <55d99105-8492-e020-bed6-82e52b5fc8a1@gmail.com> <Ypd76wmrBsIgeE3O@orome>
From:   Miaoqian Lin <linmq006@gmail.com>
In-Reply-To: <Ypd76wmrBsIgeE3O@orome>
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Hi, Thierry

On 2022/6/1 22:47, Thierry Reding wrote:
> On Wed, Jun 01, 2022 at 09:55:02PM +0800, Miaoqian Lin wrote:
>> Hi, Daniel
>>
>> On 2022/6/1 21:26, Daniel Vetter wrote:
>>> On Wed, Jun 01, 2022 at 04:20:50PM +0400, Miaoqian Lin wrote:
>>>> The pm_runtime_enable will increase power disable depth.
>>>> If the probe fails, we should use pm_runtime_disable() to balance
>>>> pm_runtime_enable().
>>>> Also call disable function in remove function.
>>>>
>>>> Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
>>>> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
>>>> ---
>>>> Changes in v3:
>>>> - call pm_runtime_disable() in v3d_platform_drm_remove
>>>> - update commit message
>>>>
>>>> Changes in v2
>>>> - put pm_runtime_disable before dma_free_wc
>>>> - rename dma_free to pm_disable
>>>>
>>>> v1: https://lore.kernel.org/r/20220105120442.14418-1-linmq006@gmail.com
>>>> v2: https://lore.kernel.org/r/20220106124657.32737-1-linmq006@gmail.com
>>> Maybe a bit late since we're at v3 already, but are there no devm_
>>> functions here that would dtrt automatically? 
>> Sorry I don't see one, or we can use devm_add_action_or_reset() to add handling
>>
>> action. something like disp_cc_sm8250_probe() in drivers/clk/qcom/dispcc-sm8250.c
>>
>> How do you think?
> Looks like there's a devm_pm_runtime_enable() helper that does exactly
> that. See commit b3636a3a2c51 ("PM: runtime: add devm_pm_runtime_enable
> helper"). I haven't seen any large janitorial series yet for that, so
> perhaps it's just not widely known yet.

Great, very helpful. Thanks for your kind reminder.

> Thierry