linux-kernel - Re: [PATCH 1/4] [PATCH 1/4] reset: simple: Add syscon device compatible

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <8a9518fdfda805f52b96e93649c9ee39274f5844.camel@pengutronix.de>
Date: Fri, 14 Feb 2025 19:03:17 +0100
From: Philipp Zabel <p.zabel@...gutronix.de>
To: Wilson Ding <dingwei@...vell.com>, "linux-kernel@...r.kernel.org"
	 <linux-kernel@...r.kernel.org>, "devicetree@...r.kernel.org"
	 <devicetree@...r.kernel.org>, "linux-arm-kernel@...ts.infradead.org"
	 <linux-arm-kernel@...ts.infradead.org>
Cc: "andrew@...n.ch" <andrew@...n.ch>, "gregory.clement@...tlin.com"
 <gregory.clement@...tlin.com>, "sebastian.hesselbarth@...il.com"
 <sebastian.hesselbarth@...il.com>, "robh@...nel.org" <robh@...nel.org>, 
 "krzk+dt@...nel.org" <krzk+dt@...nel.org>, "conor+dt@...nel.org"
 <conor+dt@...nel.org>, Sanghoon Lee <salee@...vell.com>, Geethasowjanya
 Akula <gakula@...vell.com>
Subject: Re: [PATCH 1/4] [PATCH 1/4] reset: simple: Add syscon device
 compatible

On Fr, 2025-02-14 at 17:13 +0000, Wilson Ding wrote:
> 
> > -----Original Message-----
> > From: Philipp Zabel <p.zabel@...gutronix.de>
> > Sent: Friday, February 14, 2025 3:54 AM
> > To: Wilson Ding <dingwei@...vell.com>; linux-kernel@...r.kernel.org;
> > devicetree@...r.kernel.org; linux-arm-kernel@...ts.infradead.org
> > Cc: andrew@...n.ch; gregory.clement@...tlin.com;
> > sebastian.hesselbarth@...il.com; robh@...nel.org; krzk+dt@...nel.org;
> > conor+dt@...nel.org; Sanghoon Lee <salee@...vell.com>; Geethasowjanya
> > Akula <gakula@...vell.com>
> > Subject: [EXTERNAL] Re: [PATCH 1/4] [PATCH 1/4] reset: simple: Add syscon
> > device compatible
> > 
> > On Do, 2025-02-13 at 22:58 -0800, Wilson Ding wrote:
> > > Introduce the new ops for updating reset line and getting status.
> > > Thus, the reset controller can be accessed through either direct I/O
> > > or regmap interfaces.
> > 
> > Please don't add a new layer of function pointer indirection, just add a new
> > struct reset_control_ops for the regmap variant.
> > 
> 
> If just adding a new struct reset_control_ops for the regmap variant, almost
> all the functions will be duplicated for regmap variant. 
> Besides reset_simple_regmap_assert/deassert(), we also need to have the
> regmap version of reset_simple_update().

Yes. You could also duplicate/fold update() into assert/deassert().
It is trivial enough and the compiler will do that anyway.

> Since reset_simple_reset() invokes
> reset_simple_regmap_assert/deassert(), it also needs to be
> duplicated.

That one could go through the data->rcdev.ops->assert/deassert function
pointers and be reused. But I wonder if that one function is worth the
added complexity.

> In this case, there will be too many redundant codes in this file. I doubt if
> it is worth to use the reset simple code. Maybe it's better to fork a new file
> for the syscon device, such as 'reset-simple-syscon.c'. What do you say?

That sounds sensible to me.

regards
Philipp