On Tue, Jun 07, 2022 at 04:21:57PM -0500, Bjorn Helgaas wrote: > From: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx> > > Convert firewire-ohci from legacy PCI power management to the generic power > management framework. > > Previously firewire-ohci used legacy PCI power management, and > pci_suspend() and pci_resume() were responsible for both device-specific > things and generic PCI things like saving and restoring config space and > managing power state: > > pci_suspend > software_reset <-- device-specific > pci_save_state <-- generic PCI > pci_set_power_state <-- generic PCI > pmac_ohci_off <-- device-specific > > pci_resume > pmac_ohci_on <-- device-specific > pci_set_power_state(PCI_D0) <-- generic PCI > pci_restore_state <-- generic PCI > pci_enable_device <-- generic PCI > ohci_enable <-- device-specific > > Convert to generic power management where the PCI bus PM methods do the > generic PCI things, and the driver needs only the device-specific part, > i.e., > > suspend_devices_and_enter > dpm_suspend_start(PMSG_SUSPEND) > pci_pm_suspend # PCI bus .suspend() method > pci_suspend # driver->pm->suspend > software_reset <-- device-specific > pmac_ohci_off <-- device-specific > suspend_enter > dpm_suspend_noirq(PMSG_SUSPEND) > pci_pm_suspend_noirq # PCI bus .suspend_noirq() method > pci_save_state <-- generic PCI > pci_prepare_to_sleep <-- generic PCI > pci_set_power_state > ... > dpm_resume_end(PMSG_RESUME) > pci_pm_resume # PCI bus .resume() method > pci_restore_standard_config > pci_set_power_state(PCI_D0) <-- generic PCI > pci_restore_state <-- generic PCI > pci_resume # driver->pm->resume > pmac_ohci_on <-- device-specific > ohci_enable <-- device-specific I want to point out that this changes the ordering of pmac_ohci_off() with respect to pci_save_state() and pci_set_power_state(). Previously we did those as: pci_save_state pci_set_power_state pmac_ohci_off and after this patch it would be: pmac_ohci_off pci_save_state pci_set_power_state The ordering of pmac_ohci_on() in the resume path is similarly changed. I don't know what pmac_ohci_off() and pmac_ohci_on() do, so I don't know whether this is an issue. In general, drivers don't need to do anything after their device is put in D3hot, but maybe firewire-ohci is unique in this way. > [bhelgaas: commit log] > Link: https://lore.kernel.org/r/20200720150715.624520-1-vaibhavgupta40@xxxxxxxxx > Signed-off-by: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > --- > drivers/firewire/ohci.c | 35 ++++++++--------------------------- > 1 file changed, 8 insertions(+), 27 deletions(-) > > diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c > index 17c9d825188b..aee705132330 100644 > --- a/drivers/firewire/ohci.c > +++ b/drivers/firewire/ohci.c > @@ -3165,8 +3165,7 @@ static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels) > return ret; > } > > -#ifdef CONFIG_PM > -static void ohci_resume_iso_dma(struct fw_ohci *ohci) > +static void __maybe_unused ohci_resume_iso_dma(struct fw_ohci *ohci) > { > int i; > struct iso_context *ctx; > @@ -3183,7 +3182,6 @@ static void ohci_resume_iso_dma(struct fw_ohci *ohci) > ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags); > } > } > -#endif > > static int queue_iso_transmit(struct iso_context *ctx, > struct fw_iso_packet *packet, > @@ -3789,39 +3787,24 @@ static void pci_remove(struct pci_dev *dev) > dev_notice(&dev->dev, "removed fw-ohci device\n"); > } > > -#ifdef CONFIG_PM > -static int pci_suspend(struct pci_dev *dev, pm_message_t state) > +static int __maybe_unused pci_suspend(struct device *devp) > { > + struct pci_dev *dev = to_pci_dev(devp); > struct fw_ohci *ohci = pci_get_drvdata(dev); > - int err; > > software_reset(ohci); > - err = pci_save_state(dev); > - if (err) { > - ohci_err(ohci, "pci_save_state failed\n"); > - return err; > - } > - err = pci_set_power_state(dev, pci_choose_state(dev, state)); > - if (err) > - ohci_err(ohci, "pci_set_power_state failed with %d\n", err); > pmac_ohci_off(dev); > > return 0; > } > > -static int pci_resume(struct pci_dev *dev) > +static int __maybe_unused pci_resume(struct device *devp) > { > + struct pci_dev *dev = to_pci_dev(devp); > struct fw_ohci *ohci = pci_get_drvdata(dev); > int err; > > pmac_ohci_on(dev); > - pci_set_power_state(dev, PCI_D0); > - pci_restore_state(dev); > - err = pci_enable_device(dev); > - if (err) { > - ohci_err(ohci, "pci_enable_device failed\n"); > - return err; > - } > > /* Some systems don't setup GUID register on resume from ram */ > if (!reg_read(ohci, OHCI1394_GUIDLo) && > @@ -3838,7 +3821,6 @@ static int pci_resume(struct pci_dev *dev) > > return 0; > } > -#endif > > static const struct pci_device_id pci_table[] = { > { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) }, > @@ -3847,15 +3829,14 @@ static const struct pci_device_id pci_table[] = { > > MODULE_DEVICE_TABLE(pci, pci_table); > > +static SIMPLE_DEV_PM_OPS(pci_pm_ops, pci_suspend, pci_resume); > + > static struct pci_driver fw_ohci_pci_driver = { > .name = ohci_driver_name, > .id_table = pci_table, > .probe = pci_probe, > .remove = pci_remove, > -#ifdef CONFIG_PM > - .resume = pci_resume, > - .suspend = pci_suspend, > -#endif > + .driver.pm = &pci_pm_ops, > }; > > static int __init fw_ohci_init(void) > -- > 2.25.1 >
