On Thu, Dec 09, 2021 at 10:32:45AM -0600, Bjorn Helgaas wrote: > [+cc Rafael, since I used generic PM as an example] > On Wed, Dec 08, 2021 at 09:47:56AM +0100, Greg KH wrote: ... Okay, more bikeshedding :-) > In the very common situation of PCI drivers that use generic power > management, authors *do* have to use both (example from [1]): > > ioh_gpio_probe(struct pci_dev *pdev) # pci_driver.probe() > pci_set_drvdata(pdev, chip); > > ioh_gpio_remove(struct pci_dev *pdev) # pci_driver.remove() > struct ioh_gpio *chip = pci_get_drvdata(pdev); > > ioh_gpio_suspend(struct device *dev) # pci_driver.driver.pm.suspend() > struct ioh_gpio *chip = dev_get_drvdata(dev); <-- > > The pci_driver methods receive a struct pci_dev and use the > pci_get_drvdata() wrapper. > > The generic power management methods receive a struct device and use > the underlying dev_get_drvdata(). > > It's kind of ugly that readers have to know that pci_get_drvdata() > gives you the same thing as dev_get_drvdata(). > > I guess the generic PM methods could do something like: > > pci_get_drvdata(to_pci_dev(dev)); > > but that seems a little bit circuitous. It's slightly wordier, but I > might prefer to just use this everywhere and skip the pci_* wrappers: > > dev_get_drvdata(&pdev->dev); Strictly speaking the <$BUS)_get_drvdata(<$CONTAINER>) != dev_get_drvdata(dev) it's completely up to the container handling code what to do. In 99% (or 100%?) cases it's equal, but it's not obliged to be so. > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpio/gpio-ml-ioh.c?id=v5.15#n505 -- With Best Regards, Andy Shevchenko
