Re: [PATCH] drm/rockchip: Use dev_err_probe() to simplify code

From: "Heiko Stübner" <heiko@sntech.de>
To: long.yunjian@zte.com.cn, hjc@rock-chips.com,
	Krzysztof Kozlowski <krzk@kernel.org>
Cc: andy.yan@rock-chips.com, maarten.lankhorst@linux.intel.com,
	mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com,
	simona@ffwll.ch, dri-devel@lists.freedesktop.org,
	linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org,
	fang.yumeng@zte.com.cn, mou.yi@zte.com.cn, xu.lifeng1@zte.com.cn,
	ouyang.maochun@zte.com.cn
Subject: Re: [PATCH] drm/rockchip: Use dev_err_probe() to simplify code
Date: Fri, 16 May 2025 11:58:11 +0200	[thread overview]
Message-ID: <2022996.jZfb76A358@diego> (raw)
In-Reply-To: <94e0951b-46e1-439b-9dbc-c2009a78b04b@kernel.org>

Am Donnerstag, 15. Mai 2025, 17:54:20 Mitteleuropäische Sommerzeit schrieb Krzysztof Kozlowski:
> On 15/05/2025 14:35, long.yunjian@zte.com.cn wrote:
> > From: Yumeng Fang <fang.yumeng@zte.com.cn>
> > 
> > In the probe path, dev_err() can be replaced with dev_err_probe()
> 
> That's not probe path. I am not sure if you really understand this code.

I think that is somewhat debateable.

dw_hdmi_rockchip_bind() is part of the rockchip-drm component device,
so part of its probe-path. Also I think just the presence of EPROBE_DEFER
which causes the device to re-try probing later is a nice indicator that the
code in question is _a_ probe path. (and usage of EPROBE_DEFER is an
established pattern to make that component device re-try probing later)

And the parse_dt function itself is part of that path too.

> > which will check if error code is -EPROBE_DEFER and prints the
> > error name. It also sets the defer probe reason which can be
> > checked later through debugfs.
> > 
> > Signed-off-by: Yumeng Fang <fang.yumeng@zte.com.cn>
> 
> Incomplete chain.

Yep, the patch needs a 2nd Signed-off-by line from
long.yunjian@zte.com.cn please.

Heiko