diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index 2b487d4797bd..caeb8d6d39fb 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -37,119 +37,123 @@ /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */ -#ifdef CONFIG_PM_SLEEP - -/* Coordinate handoffs between EHCI and companion controllers - * during system resume +/* + * Coordinate handoffs between EHCI and companion controllers + * during EHCI probing and system resume. */ -static DEFINE_MUTEX(companions_mutex); +static DECLARE_RWSEM(companions_rwsem); #define CL_UHCI PCI_CLASS_SERIAL_USB_UHCI #define CL_OHCI PCI_CLASS_SERIAL_USB_OHCI #define CL_EHCI PCI_CLASS_SERIAL_USB_EHCI -enum companion_action { - SET_HS_COMPANION, CLEAR_HS_COMPANION, WAIT_FOR_COMPANIONS -}; +static inline int is_ohci_or_uhci(struct pci_dev *pdev) +{ + return pdev->class == CL_OHCI || pdev->class == CL_UHCI; +} -static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd, - enum companion_action action) +typedef void (*companion_fn)(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd); + +/* Iterate over PCI devices in the same slot as pdev and call fn for each */ +static void for_each_companion(struct pci_dev *pdev, struct usb_hcd *hcd, + companion_fn fn) { struct pci_dev *companion; struct usb_hcd *companion_hcd; unsigned int slot = PCI_SLOT(pdev->devfn); - /* Iterate through other PCI functions in the same slot. - * If pdev is OHCI or UHCI then we are looking for EHCI, and - * vice versa. + /* + * Iterate through other PCI functions in the same slot. + * If the function's drvdata isn't set then it isn't bound to + * a USB host controller driver, so skip it. */ companion = NULL; for_each_pci_dev(companion) { if (companion->bus != pdev->bus || PCI_SLOT(companion->devfn) != slot) continue; - companion_hcd = pci_get_drvdata(companion); if (!companion_hcd) continue; - - /* For SET_HS_COMPANION, store a pointer to the EHCI bus in - * the OHCI/UHCI companion bus structure. - * For CLEAR_HS_COMPANION, clear the pointer to the EHCI bus - * in the OHCI/UHCI companion bus structure. - * For WAIT_FOR_COMPANIONS, wait until the OHCI/UHCI - * companion controllers have fully resumed. - */ - - if ((pdev->class == CL_OHCI || pdev->class == CL_UHCI) && - companion->class == CL_EHCI) { - /* action must be SET_HS_COMPANION */ - dev_dbg(&companion->dev, "HS companion for %s\n", - dev_name(&pdev->dev)); - hcd->self.hs_companion = &companion_hcd->self; - - } else if (pdev->class == CL_EHCI && - (companion->class == CL_OHCI || - companion->class == CL_UHCI)) { - switch (action) { - case SET_HS_COMPANION: - dev_dbg(&pdev->dev, "HS companion for %s\n", - dev_name(&companion->dev)); - companion_hcd->self.hs_companion = &hcd->self; - break; - case CLEAR_HS_COMPANION: - companion_hcd->self.hs_companion = NULL; - break; - case WAIT_FOR_COMPANIONS: - device_pm_wait_for_dev(&pdev->dev, - &companion->dev); - break; - } - } + fn(pdev, hcd, companion, companion_hcd); } } -static void set_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd) +/* + * We're about to add an EHCI controller, which will unceremoniously grab + * all the port connections away from its companions. To prevent annoying + * error messages, lock the companion's root hub and gracefully unconfigure + * it beforehand. Leave it locked until the EHCI controller is all set. + */ +static void ehci_pre_add(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd) { - mutex_lock(&companions_mutex); - dev_set_drvdata(&pdev->dev, hcd); - companion_common(pdev, hcd, SET_HS_COMPANION); - mutex_unlock(&companions_mutex); + struct usb_device *udev; + + if (is_ohci_or_uhci(companion)) { + udev = companion_hcd->self.root_hub; + usb_lock_device(udev); + usb_set_configuration(udev, 0); + } } -static void clear_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd) +/* + * Adding the EHCI controller has either succeeded or failed. Set the + * companion pointer accordingly, and in either case, reconfigure and + * unlock the root hub. + */ +static void ehci_post_add(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd) { - mutex_lock(&companions_mutex); - dev_set_drvdata(&pdev->dev, NULL); + struct usb_device *udev; - /* If pdev is OHCI or UHCI, just clear its hs_companion pointer */ - if (pdev->class == CL_OHCI || pdev->class == CL_UHCI) - hcd->self.hs_companion = NULL; - - /* Otherwise search for companion buses and clear their pointers */ - else - companion_common(pdev, hcd, CLEAR_HS_COMPANION); - mutex_unlock(&companions_mutex); + if (is_ohci_or_uhci(companion)) { + if (dev_get_drvdata(&pdev->dev)) { /* Succeeded */ + dev_dbg(&pdev->dev, "HS companion for %s\n", + dev_name(&companion->dev)); + companion_hcd->self.hs_companion = &hcd->self; + } + udev = companion_hcd->self.root_hub; + usb_set_configuration(udev, 1); + usb_unlock_device(udev); + } } -static void wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd) +/* + * We just added a non-EHCI controller. Find the EHCI controller to + * which it is a companion, and store a pointer to the bus structure. + */ +static void non_ehci_add(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd) { - /* Only EHCI controllers need to wait. - * No locking is needed because a controller cannot be resumed - * while one of its companions is getting unbound. - */ - if (pdev->class == CL_EHCI) - companion_common(pdev, hcd, WAIT_FOR_COMPANIONS); + if (is_ohci_or_uhci(pdev) && companion->class == CL_EHCI) { + dev_dbg(&pdev->dev, "FS/LS companion for %s\n", + dev_name(&companion->dev)); + hcd->self.hs_companion = &companion_hcd->self; + } } -#else /* !CONFIG_PM_SLEEP */ +/* We are removing an EHCI controller. Clear the companions' pointers. */ +static void ehci_remove(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd) +{ + if (is_ohci_or_uhci(companion)) + companion_hcd->self.hs_companion = NULL; +} -static inline void set_hs_companion(struct pci_dev *d, struct usb_hcd *h) {} -static inline void clear_hs_companion(struct pci_dev *d, struct usb_hcd *h) {} -static inline void wait_for_companions(struct pci_dev *d, struct usb_hcd *h) {} +#ifdef CONFIG_PM -#endif /* !CONFIG_PM_SLEEP */ +/* An EHCI controller must wait for its companions before resuming. */ +static void ehci_wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd, + struct pci_dev *companion, struct usb_hcd *companion_hcd) +{ + if (is_ohci_or_uhci(companion)) + device_pm_wait_for_dev(&pdev->dev, &companion->dev); +} + +#endif /* CONFIG_PM */ /*-------------------------------------------------------------------------*/ @@ -217,7 +221,7 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) driver->description)) { dev_dbg(&dev->dev, "controller already in use\n"); retval = -EBUSY; - goto clear_companion; + goto put_hcd; } hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len); if (hcd->regs == NULL) { @@ -244,16 +248,35 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) if (region == PCI_ROM_RESOURCE) { dev_dbg(&dev->dev, "no i/o regions available\n"); retval = -EBUSY; - goto clear_companion; + goto put_hcd; } } pci_set_master(dev); - retval = usb_add_hcd(hcd, hcd_irq, IRQF_SHARED); + /* Note: dev_set_drvdata must be called while holding the rwsem */ + if (dev->class == CL_EHCI) { + down_write(&companions_rwsem); + dev_set_drvdata(&dev->dev, hcd); + for_each_companion(dev, hcd, ehci_pre_add); + retval = usb_add_hcd(hcd, hcd_irq, IRQF_SHARED); + if (retval != 0) + dev_set_drvdata(&dev->dev, NULL); + for_each_companion(dev, hcd, ehci_post_add); + up_write(&companions_rwsem); + } else { + down_read(&companions_rwsem); + dev_set_drvdata(&dev->dev, hcd); + retval = usb_add_hcd(hcd, hcd_irq, IRQF_SHARED); + if (retval != 0) + dev_set_drvdata(&dev->dev, NULL); + else + for_each_companion(dev, hcd, non_ehci_add); + up_read(&companions_rwsem); + } + if (retval != 0) goto unmap_registers; - set_hs_companion(dev, hcd); if (pci_dev_run_wake(dev)) pm_runtime_put_noidle(&dev->dev); @@ -266,8 +289,7 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) release_mem_region(hcd->rsrc_start, hcd->rsrc_len); } else release_region(hcd->rsrc_start, hcd->rsrc_len); -clear_companion: - clear_hs_companion(dev, hcd); +put_hcd: usb_put_hcd(hcd); disable_pci: pci_disable_device(dev); @@ -310,14 +332,29 @@ void usb_hcd_pci_remove(struct pci_dev *dev) usb_hcd_irq(0, hcd); local_irq_enable(); - usb_remove_hcd(hcd); + /* Note: dev_set_drvdata must be called while holding the rwsem */ + if (dev->class == CL_EHCI) { + down_write(&companions_rwsem); + for_each_companion(dev, hcd, ehci_remove); + usb_remove_hcd(hcd); + dev_set_drvdata(&dev->dev, NULL); + up_write(&companions_rwsem); + } else { + /* Not EHCI; just clear the companion pointer */ + down_read(&companions_rwsem); + hcd->self.hs_companion = NULL; + usb_remove_hcd(hcd); + dev_set_drvdata(&dev->dev, NULL); + up_read(&companions_rwsem); + } + if (hcd->driver->flags & HCD_MEMORY) { iounmap(hcd->regs); release_mem_region(hcd->rsrc_start, hcd->rsrc_len); } else { release_region(hcd->rsrc_start, hcd->rsrc_len); } - clear_hs_companion(dev, hcd); + usb_put_hcd(hcd); pci_disable_device(dev); } @@ -463,8 +500,15 @@ static int resume_common(struct device *dev, int event) pci_set_master(pci_dev); if (hcd->driver->pci_resume && !HCD_DEAD(hcd)) { - if (event != PM_EVENT_AUTO_RESUME) - wait_for_companions(pci_dev, hcd); + + /* + * Only EHCI controllers have to wait for their companions. + * No locking is needed because PCI controller drivers do not + * get unbound during system resume. + */ + if (pci_dev->class == CL_EHCI && event != PM_EVENT_AUTO_RESUME) + for_each_companion(pci_dev, hcd, + ehci_wait_for_companions); retval = hcd->driver->pci_resume(hcd, event == PM_EVENT_RESTORE);