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

[Russell King - ARM Linux]

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.  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.

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