linux-kernel - Re: [PATCH 3/7] watchdog: npcm: Enable clock if provided

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: <YmpSIFHTYDsuEm85@latitude>
Date:   Thu, 28 Apr 2022 10:36:48 +0200
From:   Jonathan Neuschäfer <j.neuschaefer@....net>
To:     Guenter Roeck <linux@...ck-us.net>
Cc:     Jonathan Neuschäfer <j.neuschaefer@....net>,
        linux-clk@...r.kernel.org, openbmc@...ts.ozlabs.org,
        linux-kernel@...r.kernel.org, linux-watchdog@...r.kernel.org,
        devicetree@...r.kernel.org,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Avi Fishman <avifishman70@...il.com>,
        Tomer Maimon <tmaimon77@...il.com>,
        Tali Perry <tali.perry1@...il.com>,
        Patrick Venture <venture@...gle.com>,
        Nancy Yuen <yuenn@...gle.com>,
        Benjamin Fair <benjaminfair@...gle.com>,
        Daniel Lezcano <daniel.lezcano@...aro.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Wim Van Sebroeck <wim@...ux-watchdog.org>
Subject: Re: [PATCH 3/7] watchdog: npcm: Enable clock if provided

On Fri, Apr 22, 2022 at 11:34:17AM -0700, Guenter Roeck wrote:
> On Fri, Apr 22, 2022 at 08:30:08PM +0200, Jonathan Neuschäfer wrote:
> > On the Nuvoton WPCM450 SoC, with its upcoming clock driver, peripheral
> > clocks are individually gated and ungated. Therefore, the watchdog
> > driver must be able to ungate the watchdog clock.
> > 
> > Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@....net>
> > ---
> >  drivers/watchdog/npcm_wdt.c | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> > 
> > diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
> > index 28a24caa2627c..6d27f0e16188e 100644
> > --- a/drivers/watchdog/npcm_wdt.c
> > +++ b/drivers/watchdog/npcm_wdt.c
> > @@ -3,6 +3,7 @@
> >  // Copyright (c) 2018 IBM Corp.
> > 
> >  #include <linux/bitops.h>
> > +#include <linux/clk.h>
> >  #include <linux/delay.h>
> >  #include <linux/interrupt.h>
> >  #include <linux/kernel.h>
> > @@ -180,6 +181,7 @@ static int npcm_wdt_probe(struct platform_device *pdev)
> >  {
> >  	struct device *dev = &pdev->dev;
> >  	struct npcm_wdt *wdt;
> > +	struct clk *clk;
> >  	int irq;
> >  	int ret;
> > 
> > @@ -191,6 +193,13 @@ static int npcm_wdt_probe(struct platform_device *pdev)
> >  	if (IS_ERR(wdt->reg))
> >  		return PTR_ERR(wdt->reg);
> > 
> > +	clk = devm_clk_get_optional(&pdev->dev, NULL);
> > +	if (IS_ERR(clk))
> > +		return PTR_ERR(clk);
> > +
> > +	if (clk)
> > +		clk_prepare_enable(clk);
> > +
> 
> This needs a matching clk_disable_unprepare().

Good point. It's probably easiest if I move the clk calls to the
watchdog start/stop callbacks, then.


Thanks,
Jonathan

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)