Re: [PATCH 10/23] watchdog: of_xilinx_wdt: Convert to use device managed functions and other improvements

[Guenter Roeck]

On 4/9/19 11:38 PM, Michal Simek wrote:
> On 09. 04. 19 19:23, Guenter Roeck wrote:
> > Use device managed functions to simplify error handling, reduce
> > source code size, improve readability, and reduce the likelyhood of bugs.
> > Other improvements as listed below.
> >
> > The conversion was done automatically with coccinelle using the
> > following semantic patches. The semantic patches and the scripts
> > used to generate this commit log are available at
> > https://github.com/groeck/coccinelle-patches
> >
> > - Drop assignments to otherwise unused variables
> > - Drop empty remove function
> > - Use devm_add_action_or_reset() for calls to clk_disable_unprepare
> > - Introduce local variable 'struct device *dev' and use it instead of
> >    dereferencing it repeatedly
> > - Use devm_watchdog_register_driver() to register watchdog device
> >
> > Cc: Michal Simek <michal.simek@xxxxxxxxxx>
> > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> > ---
> >   drivers/watchdog/of_xilinx_wdt.c | 58 ++++++++++++++++++----------------------
> >   1 file changed, 26 insertions(+), 32 deletions(-)
> >
> > diff --git a/drivers/watchdog/of_xilinx_wdt.c b/drivers/watchdog/of_xilinx_wdt.c
> > index 5c977164b3e5..03786992b701 100644
> > --- a/drivers/watchdog/of_xilinx_wdt.c
> > +++ b/drivers/watchdog/of_xilinx_wdt.c
> > @@ -151,41 +151,46 @@ static u32 xwdt_selftest(struct xwdt_device *xdev)
> >   		return XWT_TIMER_FAILED;
> >   }
> >   
> > +static void xwdt_clk_disable_unprepare(void *data)
> > +{
> > +	clk_disable_unprepare(data);
> > +}
> > +
> >   static int xwdt_probe(struct platform_device *pdev)
> >   {
> > +	struct device *dev = &pdev->dev;
> >   	int rc;
> >   	u32 pfreq = 0, enable_once = 0;
> >   	struct xwdt_device *xdev;
> >   	struct watchdog_device *xilinx_wdt_wdd;
> >   
> > -	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
> > +	xdev = devm_kzalloc(dev, sizeof(*xdev), GFP_KERNEL);
> >   	if (!xdev)
> >   		return -ENOMEM;
> >   
> >   	xilinx_wdt_wdd = &xdev->xilinx_wdt_wdd;
> >   	xilinx_wdt_wdd->info = &xilinx_wdt_ident;
> >   	xilinx_wdt_wdd->ops = &xilinx_wdt_ops;
> > -	xilinx_wdt_wdd->parent = &pdev->dev;
> > +	xilinx_wdt_wdd->parent = dev;
> >   
> >   	xdev->base = devm_platform_ioremap_resource(pdev, 0);
> >   	if (IS_ERR(xdev->base))
> >   		return PTR_ERR(xdev->base);
> >   
> > -	rc = of_property_read_u32(pdev->dev.of_node, "xlnx,wdt-interval",
> > +	rc = of_property_read_u32(dev->of_node, "xlnx,wdt-interval",
> >   				  &xdev->wdt_interval);
> >   	if (rc)
> > -		dev_warn(&pdev->dev,
> > -			 "Parameter \"xlnx,wdt-interval\" not found\n");
> > +		dev_warn(dev, "Parameter \"xlnx,wdt-interval\" not found\n");
> >   
> > -	rc = of_property_read_u32(pdev->dev.of_node, "xlnx,wdt-enable-once",
> > +	rc = of_property_read_u32(dev->of_node, "xlnx,wdt-enable-once",
> >   				  &enable_once);
> >   	if (rc)
> > -		dev_warn(&pdev->dev,
> > +		dev_warn(dev,
> >   			 "Parameter \"xlnx,wdt-enable-once\" not found\n");
> >   
> >   	watchdog_set_nowayout(xilinx_wdt_wdd, enable_once);
> >   
> > -	xdev->clk = devm_clk_get(&pdev->dev, NULL);
> > +	xdev->clk = devm_clk_get(dev, NULL);
> >   	if (IS_ERR(xdev->clk)) {
> >   		if (PTR_ERR(xdev->clk) != -ENOENT)
> >   			return PTR_ERR(xdev->clk);
> > @@ -196,10 +201,10 @@ static int xwdt_probe(struct platform_device *pdev)
> >   		 */
> >   		xdev->clk = NULL;
> >   
> > -		rc = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
> > +		rc = of_property_read_u32(dev->of_node, "clock-frequency",
> >   					  &pfreq);
> >   		if (rc)
> > -			dev_warn(&pdev->dev,
> > +			dev_warn(dev,
> >   				 "The watchdog clock freq cannot be obtained\n");
> >   	} else {
> >   		pfreq = clk_get_rate(xdev->clk);
> > @@ -218,44 +223,34 @@ static int xwdt_probe(struct platform_device *pdev)
> >   
> >   	rc = clk_prepare_enable(xdev->clk);
> >   	if (rc) {
> > -		dev_err(&pdev->dev, "unable to enable clock\n");
> > +		dev_err(dev, "unable to enable clock\n");
> >   		return rc;
> >   	}
> > +	rc = devm_add_action_or_reset(dev, xwdt_clk_disable_unprepare,
> > +				      xdev->clk);
> > +	if (rc)
> > +		return rc;
> >   
> >   	rc = xwdt_selftest(xdev);
> >   	if (rc == XWT_TIMER_FAILED) {
> > -		dev_err(&pdev->dev, "SelfTest routine error\n");
> > -		goto err_clk_disable;
> > +		dev_err(dev, "SelfTest routine error\n");
> > +		return rc;
> >   	}
> >   
> > -	rc = watchdog_register_device(xilinx_wdt_wdd);
> > +	rc = devm_watchdog_register_device(dev, xilinx_wdt_wdd);
> >   	if (rc) {
> > -		dev_err(&pdev->dev, "Cannot register watchdog (err=%d)\n", rc);
> > -		goto err_clk_disable;
> > +		dev_err(dev, "Cannot register watchdog (err=%d)\n", rc);
> > +		return rc;
> >   	}
> >   
> >   	clk_disable(xdev->clk);
> >   
> > -	dev_info(&pdev->dev, "Xilinx Watchdog Timer at %p with timeout %ds\n",
> > +	dev_info(dev, "Xilinx Watchdog Timer at %p with timeout %ds\n",
> >   		 xdev->base, xilinx_wdt_wdd->timeout);
> >   
> >   	platform_set_drvdata(pdev, xdev);
> >   
> >   	return 0;
> > -err_clk_disable:
> > -	clk_disable_unprepare(xdev->clk);
> > -
> > -	return rc;
> > -}
> > -
> > -static int xwdt_remove(struct platform_device *pdev)
> > -{
> > -	struct xwdt_device *xdev = platform_get_drvdata(pdev);
> > -
> > -	watchdog_unregister_device(&xdev->xilinx_wdt_wdd);
> > -	clk_disable_unprepare(xdev->clk);
> > -
> > -	return 0;
> >   }
> >   
> >   /**
> > @@ -303,7 +298,6 @@ MODULE_DEVICE_TABLE(of, xwdt_of_match);
> >   
> >   static struct platform_driver xwdt_driver = {
> >   	.probe       = xwdt_probe,
> > -	.remove      = xwdt_remove,
> >   	.driver = {
> >   		.name  = WATCHDOG_NAME,
> >   		.of_match_table = xwdt_of_match,
>
> Looks good to me. I would prefer to do it via 3 patches but I will let
> Wim to comment.

I could do that, but the total series is already more than 60 patches.
Splitting them up would mean hundreds of patches.

> Acked-by: Michal Simek <michal.simek@xxxxxxxxxx>

Thanks,
Guenter