RE: [char-misc-next] mei: simplify error handling via devres function.

[Winkler, Tomas]

> 
> On Fri, Jan 20, 2017 at 7:22 PM, Tomas Winkler <tomas.winkler@xxxxxxxxx>
> wrote:
> > Use devm_ and pcim_ functions to make error handling simpler and code
> > smaller and tidier.
> >
> > Based on original patch by
> > mei: me: use managed functions pcim_* and devm_* Andy Shevchenko
> > <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > https://lkml.org/lkml/2016/2/1/339
> 
> Perhaps you may leave SoB.
> But let me review the code.

No problem, though we also had some internal code before, you were just first to send it out ;)

> 
> > Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
> > Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
> 
> > - * Return: The mei_device_device pointer on success, NULL on failure.
> > + * Return: The mei_device pointer on success, NULL on failure.
> 
> This is not related.
> 
> > -struct mei_device *mei_me_dev_init(struct pci_dev *pdev,
> > -                                  const struct mei_cfg *cfg)
> > +struct mei_device *devm_mei_me_init(struct pci_dev *pdev,
> > +                                   const struct mei_cfg *cfg)
> 
> It's not exactly in devm_ namespace. (They have no corresponding
> devm_*_fini, etc.) Better to leave same name in spite of calling devm_* inside.

Okay, got it.
> 
> > -struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
> > +struct mei_device *devm_mei_txe_init(struct pci_dev *pdev)
> 
> Ditto.
> 
> >  end:
> 
> > +       pci_set_drvdata(pdev, NULL);
> 
> Not needed.
Please explain, we rely on pci_get_drvdata() returning NULL when unregistered. 
> 
> >  static void mei_me_remove(struct pci_dev *pdev)  {
> >         struct mei_device *dev;
> > -       struct mei_me_hw *hw;
> >
> >         dev = pci_get_drvdata(pdev);
> >         if (!dev)
> > @@ -276,33 +260,19 @@ static void mei_me_remove(struct pci_dev *pdev)
> >         if (mei_pg_is_enabled(dev))
> >                 pm_runtime_get_noresume(&pdev->dev);
> 
> > +       pci_set_drvdata(pdev, NULL);
> 
> Ditto.
> 
> > -       free_irq(pdev->irq, dev);
> > +       devm_free_irq(&pdev->dev, pdev->irq, dev);
> >         pci_disable_msi(pdev);
> 
> All three not needed
I believe we need it on suspend as we are going over  irq request again in resume.  Please provide more info you if you still insist. 
> 
> >         return 0;
> 
> > @@ -75,22 +64,22 @@ static int mei_txe_probe(struct pci_dev *pdev,
> > const struct pci_device_id *ent)  {
> >         struct mei_device *dev;
> >         struct mei_txe_hw *hw;
> 
> > +       const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR);
> 
> First line?
Please be more verbose.
> 
> > +       memcpy(hw->mem_addr, pcim_iomap_table(pdev),
> > + sizeof(hw->mem_addr));
> 
> Why?
> It is kept by PCI core, you don't need a copy.

There is no simple accessor for that, it's easier to copy the two dwords then going over the function calls. 

> >  end:
> 
> > +       pci_set_drvdata(pdev, NULL);
> 
> Redundant.
> 
> >  static void mei_txe_remove(struct pci_dev *pdev)  {
> 
> > +       pci_set_drvdata(pdev, NULL);
> 
> Ditto.
> 
> > @@ -256,7 +210,7 @@ static int mei_txe_pci_suspend(struct device
> > *device)
> 
> > -       free_irq(pdev->irq, dev);
> > +       devm_free_irq(&pdev->dev, pdev->irq, dev);
> >         pci_disable_msi(pdev);
> 
> All are redundant.

Thanks
Tomas