Re: [PATCH 2/2] fpga-manager: Add Socfpga Arria10 support

From: atull
Date: Wed Jul 13 2016 - 10:52:47 EST


On Tue, 12 Jul 2016, Russell King - ARM Linux wrote:

> On Tue, Jul 12, 2016 at 02:31:05PM -0700, Moritz Fischer wrote:
> > On Tue, Jul 12, 2016 at 12:07 PM, Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx> wrote:
> > > + priv->clk = devm_clk_get(dev, NULL);
> > > + if (IS_ERR(priv->clk)) {
> > > + dev_err(dev, "no clock specified\n");
> > > + return PTR_ERR(priv->clk);
> > > + }
> > > +
> > > + ret = clk_prepare_enable(priv->clk);
> > > + if (ret) {
> > > + dev_err(dev, "could not enable clock\n");
> > > + clk_put(priv->clk);
> >
> > Seen that you used devm_clk_get() is this one necessary?
>
> That's actually a bug.

Yes, it's wrong. And not needed anyway.

> Never clk_put() a devm_clk_get()'d clock.
> devm_clk_put() is what you want if provided. However, I think
> this clk_put() call is useless here.
>
> > > +static int socfpga_a10_fpga_remove(struct platform_device *pdev)
> > > +{
> > > + struct fpga_manager *mgr = platform_get_drvdata(pdev);
> > > + struct a10_fpga_priv *priv = mgr->priv;
> > > +
> > > + fpga_mgr_unregister(&pdev->dev);
> > > + clk_disable_unprepare(priv->clk);
> > > + clk_put(priv->clk);
> >
> > Same here, if needed at all shouldn't it be devm_clk_put() ?
>
> And also useless here, as the whole point of the devm_* stuff is to
> clean up the resources that were claimed on probe failure or when
> the device is unbound from its driver.

Thanks for pointing this out. I'll take out the clk_put's.

Alan

>
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