linux-kernel - Re: [PATCH v4 10/18] pinctrl: eyeq5: add platform driver

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]

Date: Thu, 1 Feb 2024 17:47:52 +0100
From: Linus Walleij <linus.walleij@...aro.org>
To: Théo Lebrun <theo.lebrun@...tlin.com>
Cc: Gregory CLEMENT <gregory.clement@...tlin.com>, 
	Michael Turquette <mturquette@...libre.com>, Stephen Boyd <sboyd@...nel.org>, 
	Rob Herring <robh+dt@...nel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>, Conor Dooley <conor+dt@...nel.org>, 
	Thomas Bogendoerfer <tsbogend@...ha.franken.de>, Rafał Miłecki <rafal@...ecki.pl>, 
	Philipp Zabel <p.zabel@...gutronix.de>, 
	Vladimir Kondratiev <vladimir.kondratiev@...ileye.com>, linux-mips@...r.kernel.org, 
	linux-clk@...r.kernel.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, Thomas Petazzoni <thomas.petazzoni@...tlin.com>, 
	Tawfik Bayouk <tawfik.bayouk@...ileye.com>, linux-gpio@...r.kernel.org
Subject: Re: [PATCH v4 10/18] pinctrl: eyeq5: add platform driver

On Thu, Feb 1, 2024 at 11:24 AM Théo Lebrun <theo.lebrun@...tlin.com> wrote:

> > Can't you just use regmap MMIO to access the banks then...?
> >
> > Maybe it doesn't add much here. I'm not sure.
>
> Indeed, I went the minimalist route. You tell me if you'd prefer an MMIO
> regmap.

I'm not sure, because it might be that it adds more overhead than
it saves and then it is pointless.

> I've not seen any helper to get a regmap based on a resource, targeting
> by name. Is the expected procedure to acquire the resource then create
> a regmap config then call devm_regmap_init_mmio()?

No... haven't seen such a thing.

> > > +                          enum eq5p_bank bank, enum eq5p_regs reg, int bit)
> > > +{
> > > +       u32 val = readl(pctrl->base + eq5p_regs[bank][reg]);
> > > +
> > > +       return (val & BIT(bit)) != 0;
> > > +}
> >
> > Maybe add a check for bit > 31?
>
> Will do. I like that sort of defensive programming. What behavior would
> you expect?
>  - WARN_ON(bit > 31) and return false?
>  - Just return false?
>  - Something else?

Your pick is as good as mine :D
I let the author choose what to do there.

Yours,
Linus Walleij