diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/core/hcd-pci.c | 151 |
1 files changed, 91 insertions, 60 deletions
diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index b9a3dae..71b4a8d 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -33,7 +33,7 @@ #include "hcd.h" -/* PCI-based HCs are normal, but custom bus glue should be ok */ +/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */ /*-------------------------------------------------------------------------*/ @@ -67,8 +67,8 @@ int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id) if (pci_enable_device (dev) < 0) return -ENODEV; - dev->current_state = 0; - dev->dev.power.power_state = 0; + dev->current_state = PCI_D0; + dev->dev.power.power_state = PMSG_ON; if (!dev->irq) { dev_err (&dev->dev, @@ -186,26 +186,14 @@ EXPORT_SYMBOL (usb_hcd_pci_remove); #ifdef CONFIG_PM -static char __attribute_used__ *pci_state(u32 state) -{ - switch (state) { - case 0: return "D0"; - case 1: return "D1"; - case 2: return "D2"; - case 3: return "D3hot"; - case 4: return "D3cold"; - } - return NULL; -} - /** * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD * @dev: USB Host Controller being suspended - * @state: state that the controller is going into + * @message: semantics in flux * * Store this function in the HCD's struct pci_driver as suspend(). */ -int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) +int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message) { struct usb_hcd *hcd; int retval = 0; @@ -213,13 +201,23 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) hcd = pci_get_drvdata(dev); + /* FIXME until the generic PM interfaces change a lot more, this + * can't use PCI D1 and D2 states. For example, the confusion + * between messages and states will need to vanish, and messages + * will need to provide a target system state again. + * + * It'll be important to learn characteristics of the target state, + * especially on embedded hardware where the HCD will often be in + * charge of an external VBUS power supply and one or more clocks. + * Some target system states will leave them active; others won't. + * (With PCI, that's often handled by platform BIOS code.) + */ + /* even when the PCI layer rejects some of the PCI calls * below, HCs can try global suspend and reduce DMA traffic. * PM-sensitive HCDs may already have done this. */ has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM); - if (state > 4) - state = 4; switch (hcd->state) { @@ -228,7 +226,7 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) */ case HC_STATE_RUNNING: hcd->state = HC_STATE_QUIESCING; - retval = hcd->driver->suspend (hcd, state); + retval = hcd->driver->suspend (hcd, message); if (retval) { dev_dbg (hcd->self.controller, "suspend fail, retval %d\n", @@ -246,14 +244,11 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) * have been called, otherwise root hub timers still run ... */ case HC_STATE_SUSPENDED: - if (state <= dev->current_state) - break; - - /* no DMA or IRQs except in D0 */ - if (!dev->current_state) { + /* no DMA or IRQs except when HC is active */ + if (dev->current_state == PCI_D0) { + free_irq (hcd->irq, hcd); pci_save_state (dev); pci_disable_device (dev); - free_irq (hcd->irq, hcd); } if (!has_pci_pm) { @@ -261,25 +256,19 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) break; } - /* POLICY: ignore D1/D2/D3hot differences; - * we know D3hot will always work. + /* NOTE: dev->current_state becomes nonzero only here, and + * only for devices that support PCI PM. Also, exiting + * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset + * some device state (e.g. as part of clock reinit). */ - retval = pci_set_power_state (dev, state); - if (retval < 0 && state < 3) { - retval = pci_set_power_state (dev, 3); - if (retval == 0) - state = 3; - } + retval = pci_set_power_state (dev, PCI_D3hot); if (retval == 0) { - dev_dbg (hcd->self.controller, "--> PCI %s\n", - pci_state(dev->current_state)); -#ifdef CONFIG_USB_SUSPEND - pci_enable_wake (dev, state, hcd->remote_wakeup); - pci_enable_wake (dev, 4, hcd->remote_wakeup); -#endif + dev_dbg (hcd->self.controller, "--> PCI D3\n"); + pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup); + pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup); } else if (retval < 0) { - dev_dbg (&dev->dev, "PCI %s suspend fail, %d\n", - pci_state(state), retval); + dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n", + retval); (void) usb_hcd_pci_resume (dev); break; } @@ -287,13 +276,14 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, u32 state) default: dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n", hcd->state); + WARN_ON(1); retval = -EINVAL; break; } /* update power_state **ONLY** to make sysfs happier */ if (retval == 0) - dev->dev.power.power_state = state; + dev->dev.power.power_state = message; return retval; } EXPORT_SYMBOL (usb_hcd_pci_suspend); @@ -308,7 +298,6 @@ int usb_hcd_pci_resume (struct pci_dev *dev) { struct usb_hcd *hcd; int retval; - int has_pci_pm; hcd = pci_get_drvdata(dev); if (hcd->state != HC_STATE_SUSPENDED) { @@ -316,31 +305,73 @@ int usb_hcd_pci_resume (struct pci_dev *dev) "can't resume, not suspended!\n"); return 0; } - has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM); - /* D3cold resume isn't usually reported this way... */ - dev_dbg(hcd->self.controller, "resume from PCI %s%s\n", - pci_state(dev->current_state), - has_pci_pm ? "" : " (legacy)"); + /* NOTE: chip docs cover clean "real suspend" cases (what Linux + * calls "standby", "suspend to RAM", and so on). There are also + * dirty cases when swsusp fakes a suspend in "shutdown" mode. + */ + if (dev->current_state != PCI_D0) { +#ifdef DEBUG + int pci_pm; + u16 pmcr; + + pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM); + pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr); + pmcr &= PCI_PM_CTRL_STATE_MASK; + if (pmcr) { + /* Clean case: power to USB and to HC registers was + * maintained; remote wakeup is easy. + */ + dev_dbg(hcd->self.controller, "resume from PCI D%d\n", + pmcr); + } else { + /* Clean: HC lost Vcc power, D0 uninitialized + * + Vaux may have preserved port and transceiver + * state ... for remote wakeup from D3cold + * + or not; HCD must reinit + re-enumerate + * + * Dirty: D0 semi-initialized cases with swsusp + * + after BIOS init + * + after Linux init (HCD statically linked) + */ + dev_dbg(hcd->self.controller, + "PCI D0, from previous PCI D%d\n", + dev->current_state); + } +#endif + pci_enable_wake (dev, dev->current_state, 0); + pci_enable_wake (dev, PCI_D3cold, 0); + } else { + /* Same basic cases: clean (powered/not), dirty */ + dev_dbg(hcd->self.controller, "PCI legacy resume\n"); + } + + /* NOTE: the PCI API itself is asymmetric here. We don't need to + * pci_set_power_state(PCI_D0) since that's part of re-enabling; + * but that won't re-enable bus mastering. Yet pci_disable_device() + * explicitly disables bus mastering... + */ + retval = pci_enable_device (dev); + if (retval < 0) { + dev_err (hcd->self.controller, + "can't re-enable after resume, %d!\n", retval); + return retval; + } + pci_set_master (dev); + pci_restore_state (dev); + + dev->dev.power.power_state = PMSG_ON; hcd->state = HC_STATE_RESUMING; - - if (has_pci_pm) - pci_set_power_state (dev, 0); - dev->dev.power.power_state = 0; + hcd->saw_irq = 0; retval = request_irq (dev->irq, usb_hcd_irq, SA_SHIRQ, - hcd->driver->description, hcd); + hcd->irq_descr, hcd); if (retval < 0) { dev_err (hcd->self.controller, "can't restore IRQ after resume!\n"); + usb_hc_died (hcd); return retval; } - hcd->saw_irq = 0; - pci_restore_state (dev); -#ifdef CONFIG_USB_SUSPEND - pci_enable_wake (dev, dev->current_state, 0); - pci_enable_wake (dev, 4, 0); -#endif retval = hcd->driver->resume (hcd); if (!HC_IS_RUNNING (hcd->state)) { |
