linux-kernel - Re: [PATCH v3 3/3] i2c: rk3x: Add check for clk

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: <y4xv4lduinhjbhzt64erjw3er5w3s2tcwzjxxdknoudaefupxq@fbqf4esensnk>
Date: Tue, 19 Nov 2024 23:03:08 +0100
From: Andi Shyti <andi.shyti@...nel.org>
To: Jiasheng Jiang <jiashengjiangcool@...il.com>
Cc: dianders@...omium.org, rmk@...-67.arm.linux.org.uk, 
	max.schwarz@...ine.de, david.wu@...k-chips.com, heiko@...ech.de, vz@...ia.com, 
	wsa@...nel.org, manabian@...il.com, linux-arm-kernel@...ts.infradead.org, 
	linux-rockchip@...ts.infradead.org, linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 3/3] i2c: rk3x: Add check for clk_enable()

Hi Jiasheng,

> > >  static u32 rk3x_i2c_func(struct i2c_adapter *adap)
> > > @@ -1365,9 +1389,12 @@ static int rk3x_i2c_probe(struct platform_device *pdev)
> > >       }
> > >
> > >       clk_rate = clk_get_rate(i2c->clk);
> > > -     rk3x_i2c_adapt_div(i2c, clk_rate);
> > > +     ret = rk3x_i2c_adapt_div(i2c, clk_rate);
> > >       clk_disable(i2c->clk);
> >
> > you can't disable a clock that has failed to enable, right?
> >
> > BTW, although I like this patch (or at least I don't dislike), I
> > still want to check whether it's wanted or not.
> >
> > Andi
> >
> 
> Thank you for your advice. I have carefully reviewed the patch.
> There are two clocks: "i2c->clk" and "i2c->pclk".
> The "i2c->clk" is enabled and disabled in rk3x_i2c_probe(),
> while the "i2c->pclk" is managed within rk3x_i2c_adapt_div().
> Thus, the "i2c->clk" has already been enabled at this point.

yes, that's correct, that's a fast review and anyway your patch
doesn't have anything to do with this.

BTW, did you have real failure experience here or is it just
speculation?

Thanks,
Andi