Re: [PATCH 1/5] iTCO_wdt: Expose watchdog properties using platform data

Aaron Sierra
2015-07-28T19:17:41Z

> > > > @@ -933,7 +956,7 @@ gpe0_done:
> > > > lpc_chipset_info[priv->chipset].use_gpio = ret;
> > > > lpc_ich_enable_gpio_space(dev);
> > > >
> > > > - lpc_ich_finalize_cell(dev, &lpc_ich_cells[LPC_GPIO]);
> > > > + lpc_ich_finalize_gpio_cell(dev);
> > > > ret = mfd_add_devices(&dev->dev, PLATFORM_DEVID_AUTO,
> > > > &lpc_ich_cells[LPC_GPIO], 1, NULL, 0, NULL);
> > > >
> > > > @@ -1007,7 +1030,10 @@ static int lpc_ich_init_wdt(struct pci_dev *dev)
> > > > res->end = base_addr + ACPIBASE_PMC_END;
> > > > }
> > > >
> > > > - lpc_ich_finalize_cell(dev, &lpc_ich_cells[LPC_WDT]);
> > > > + ret = lpc_ich_finalize_wdt_cell(dev);
> > > > + if (ret)
> > > > + goto wdt_done;
> > > > +
> > > > ret = mfd_add_devices(&dev->dev, PLATFORM_DEVID_AUTO,
> > > > &lpc_ich_cells[LPC_WDT], 1, NULL, 0, NULL);
> > >
> > > Why do you have an mfd_add_devices() call for each device?
> >
> > Good question. This call has been present since March 2012 when support
> > was first added for iTCO_wdt in commit 887c8ec7219f ("watchdog: Convert
> > iTCO_wdt driver to mfd model").
> >
> > There's no good reason that I can see. Aaron?

I chose to call mfd_add_devices() in each device init function
because I thought it was the easiest way to avoid registering an
incomplete/invalid MFD cell should an error occur during init.

That way device registration wouldn't be an all-or-nothing affair.

Doesn't mfd_add_devices() bail out after the first unsuccessful
mfd to platform device translation?

-Aaron S.