Re: [PATCH 2/7] watchdog: jz4740: Use devm_* functions

[Paul Cercueil]

Le jeu. 28 déc. 2017 à 21:19, Guenter Roeck <linux@xxxxxxxxxxxx> a 
écrit :
> On 12/28/2017 11:59 AM, Paul Cercueil wrote:
> > Hi Guenter,
> >
> > Le jeu. 28 déc. 2017 à 18:48, Guenter Roeck <linux@xxxxxxxxxxxx> a 
> > écrit :
> > > On 12/28/2017 08:29 AM, Paul Cercueil wrote:
> > > > - Use devm_clk_get instead of clk_get
> > > > - Use devm_watchdog_register_device instead of 
> > > > watchdog_register_device
> > > >
> > > > Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> > > > ---
> > > >   drivers/watchdog/jz4740_wdt.c | 27 ++++++++-------------------
> > > >   1 file changed, 8 insertions(+), 19 deletions(-)
> > > >
> > > > diff --git a/drivers/watchdog/jz4740_wdt.c 
> > > > b/drivers/watchdog/jz4740_wdt.c
> > > > index 6955deb100ef..92d6ca8ceb49 100644
> > > > --- a/drivers/watchdog/jz4740_wdt.c
> > > > +++ b/drivers/watchdog/jz4740_wdt.c
> > > > @@ -178,40 +178,29 @@ static int jz4740_wdt_probe(struct 
> > > > platform_device *pdev)
> > > >         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > >       drvdata->base = devm_ioremap_resource(&pdev->dev, res);
> > > > -    if (IS_ERR(drvdata->base)) {
> > > > -        ret = PTR_ERR(drvdata->base);
> > > > -        goto err_out;
> > > > -    }
> > > > +    if (IS_ERR(drvdata->base))
> > > > +        return PTR_ERR(drvdata->base);
> > > >   -    drvdata->rtc_clk = clk_get(&pdev->dev, "rtc");
> > > > +    drvdata->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
> > > >       if (IS_ERR(drvdata->rtc_clk)) {
> > > >           dev_err(&pdev->dev, "cannot find RTC clock\n");
> > > > -        ret = PTR_ERR(drvdata->rtc_clk);
> > > > -        goto err_out;
> > > > +        return PTR_ERR(drvdata->rtc_clk);
> > > >       }
> > > >   -    ret = watchdog_register_device(&drvdata->wdt);
> > > > +    ret = devm_watchdog_register_device(&pdev->dev, 
> > > > &drvdata->wdt);
> > > >       if (ret < 0)
> > > > -        goto err_disable_clk;
> > > > +        return ret;
> > > >         platform_set_drvdata(pdev, drvdata);
> > > > -    return 0;
> > > >   -err_disable_clk:
> > > > -    clk_put(drvdata->rtc_clk);
> > > > -err_out:
> > > > -    return ret;
> > > > +    return 0;
> > > >   }
> > > >     static int jz4740_wdt_remove(struct platform_device *pdev)
> > > >   {
> > > >       struct jz4740_wdt_drvdata *drvdata = 
> > > > platform_get_drvdata(pdev);
> > > >   -    jz4740_wdt_stop(&drvdata->wdt);
> > > > -    watchdog_unregister_device(&drvdata->wdt);
> > > > -    clk_put(drvdata->rtc_clk);
> > > > -
> > > > -    return 0;
> > > > +    return jz4740_wdt_stop(&drvdata->wdt);
> > >
> > > If the watchdog is running, the module can not be unloaded. Even if 
> > > that wasn't
> > > the case, this defeats both WDIOF_MAGICCLOSE and 
> > > watchdog_set_nowayout().
> > > Are you sure this is what you want ? If so, please call
> > > watchdog_stop_on_unregister() before registration; this clarifies 
> > > that this
> > > is what you want, and you can drop the remove function.
> > >
> > > Thanks,
> > > Guenter
> >
> > This patch does not change the behaviour. We always used that driver 
> > built-in; what
> > should the behaviour be when unloading the module? Keep the watchdog 
> > hardware running
> > if configured for 'nowayout'?
>
> One can still unload the driver. If you are fine with 
> bypassing/dfeating nowayout
> and WDIOF_MAGICCLOSE, may I ask why those are enabled in the first 
> place ?

Who knows? That code is very old :)
I'm fine with removing the remove() function completely, if you think 
it makes more sense.

Thanks,
-Paul