From: Rafael J. Wysocki <rjw@xxxxxxx> The radeonfb driver needs to program the device's PMCSR directly due to some quirky hardware it has to handle (see http://bugzilla.kernel.org/show_bug.cgi?id=12846 for details) and after doing that it needs to call the platform (usually ACPI) to finish the power transition of the device. Currently it uses pci_set_power_state() for this purpose, however making a specific assumption about the internal behavior of this function, which has changed recently so that this assumption is no longer satisfied. For this reason, change platform_pci_set_power_state() into an exported function so that the radeonfb driver can use it directly instead of calling it via pci_set_power_state(). Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> --- drivers/pci/pci.c | 68 +++++++++++++++++++++++++++++----------------------- include/linux/pci.h | 1 2 files changed, 40 insertions(+), 29 deletions(-) Index: linux-2.6/drivers/pci/pci.c =================================================================== --- linux-2.6.orig/drivers/pci/pci.c +++ linux-2.6/drivers/pci/pci.c @@ -398,12 +398,6 @@ static inline bool platform_pci_power_ma return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false; } -static inline int platform_pci_set_power_state(struct pci_dev *dev, - pci_power_t t) -{ - return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS; -} - static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev) { return pci_platform_pm ? @@ -540,6 +534,31 @@ void pci_update_current_state(struct pci } /** + * platform_pci_set_power_state - Call platform to change device power state + * @dev: PCI device to handle + * @state: State to put the device into + * + * Allow the platform to change the power state of the device, for example via + * ACPI _PR0, _PS0 or some such. + */ +int platform_pci_set_power_state(struct pci_dev *dev, pci_power_t state) +{ + int error = 0; + + if (!pci_platform_pm) + return -ENOSYS; + + if (pci_platform_pm->is_manageable(dev)) + error = pci_platform_pm->set_state(dev, state); + + if (!error) + pci_update_current_state(dev, state); + + return error; +} +EXPORT_SYMBOL_GPL(platform_pci_set_power_state); + +/** * pci_set_power_state - Set the power state of a PCI device * @dev: PCI device to handle. * @state: PCI power state (D0, D1, D2, D3hot) to put the device into. @@ -556,7 +575,7 @@ void pci_update_current_state(struct pci */ int pci_set_power_state(struct pci_dev *dev, pci_power_t state) { - int error; + int error, platform_error = -ENODEV; /* bound the state we're entering */ if (state > PCI_D3hot) @@ -570,36 +589,27 @@ int pci_set_power_state(struct pci_dev * * it into D0 (which would only happen on boot). */ return 0; + else if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3)) + /* + * This device is quirked not to be put into D3, so don't put it + * in D3 + */ + return 0; /* Check if we're already there */ if (dev->current_state == state) return 0; - if (state == PCI_D0) { - /* - * Allow the platform to change the state, for example via ACPI - * _PR0, _PS0 and some such, but do not trust it. - */ - int ret = platform_pci_power_manageable(dev) ? - platform_pci_set_power_state(dev, PCI_D0) : 0; - if (!ret) - pci_update_current_state(dev, PCI_D0); - } - /* This device is quirked not to be put into D3, so - don't put it in D3 */ - if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3)) - return 0; + if (state == PCI_D0) + platform_error = platform_pci_set_power_state(dev, PCI_D0); error = pci_raw_set_power_state(dev, state); - if (state > PCI_D0 && platform_pci_power_manageable(dev)) { - /* Allow the platform to finalize the transition */ - int ret = platform_pci_set_power_state(dev, state); - if (!ret) { - pci_update_current_state(dev, state); - error = 0; - } - } + if (state > PCI_D0) + platform_error = platform_pci_set_power_state(dev, state); + + if (!platform_error) + error = 0; return error; } Index: linux-2.6/include/linux/pci.h =================================================================== --- linux-2.6.orig/include/linux/pci.h +++ linux-2.6/include/linux/pci.h @@ -689,6 +689,7 @@ size_t pci_get_rom_size(struct pci_dev * /* Power management related routines */ int pci_save_state(struct pci_dev *dev); int pci_restore_state(struct pci_dev *dev); +int platform_pci_set_power_state(struct pci_dev *dev, pci_power_t state); int pci_set_power_state(struct pci_dev *dev, pci_power_t state); pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state); bool pci_pme_capable(struct pci_dev *dev, pci_power_t state); _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
