Of interest to devel@ ----- Forwarded message from David Brownell <[EMAIL PROTECTED]> -----
From: David Brownell <[EMAIL PROTECTED]> Date: Thu, 5 Apr 2007 12:48:56 -0700 To: [email protected], [EMAIL PROTECTED] Subject: [linux-pm] [patch 2.6.21-rc5-git 1/3] new platform_enable_wake() hook; use it in PCI This defines a platform hook to enable/disable a device as a wakeup event source. It's initially for use with ACPI, but more generally it could be used whenever enable_irq_wake()/disable_irq_wake() don't suffice. The hook is called -- if available -- inside pci_enable_wake(); and the semantics of that call are enhanced so that support for PCI PME# is no longer needed. It can now work for devices with "legacy PCI PM", when platform support allows it. (That support would use some board-specific signal for for the same purpose as PME#.) Signed-off-by: David Brownell <[EMAIL PROTECTED]> --- drivers/base/power/main.c | 3 ++ drivers/pci/pci.c | 61 ++++++++++++++++++++++++++++++++-------------- include/linux/pm.h | 5 +++ 3 files changed, 51 insertions(+), 18 deletions(-) --- g26.orig/include/linux/pm.h 2007-04-04 12:26:00.000000000 -0700 +++ g26/include/linux/pm.h 2007-04-04 13:03:34.000000000 -0700 @@ -273,6 +273,11 @@ extern void __suspend_report_result(cons __suspend_report_result(__FUNCTION__, fn, ret); \ } while (0) +/* platform hook to activate device wakeup capability, if + * that's not already handled by enable_irq_wake() etc + */ +extern int (*platform_enable_wakeup)(struct device *dev, int is_on); + #else /* !CONFIG_PM */ static inline int device_suspend(pm_message_t state) --- g26.orig/drivers/base/power/main.c 2007-04-04 13:03:33.000000000 -0700 +++ g26/drivers/base/power/main.c 2007-04-04 13:03:34.000000000 -0700 @@ -29,6 +29,9 @@ LIST_HEAD(dpm_off_irq); DECLARE_MUTEX(dpm_sem); DECLARE_MUTEX(dpm_list_sem); +int (*platform_enable_wakeup)(struct device *dev, int is_on) = NULL; + + /** * device_pm_set_parent - Specify power dependency. * @dev: Device who needs power. --- g26.orig/drivers/pci/pci.c 2007-04-04 12:26:06.000000000 -0700 +++ g26/drivers/pci/pci.c 2007-04-04 13:31:37.000000000 -0700 @@ -891,31 +891,53 @@ pci_disable_device(struct pci_dev *dev) } /** - * pci_enable_wake - enable device to generate PME# when suspended - * @dev: - PCI device to operate on - * @state: - Current state of device. - * @enable: - Flag to enable or disable generation - * - * Set the bits in the device's PM Capabilities to generate PME# when - * the system is suspended. - * - * -EIO is returned if device doesn't have PM Capabilities. - * -EINVAL is returned if device supports it, but can't generate wake events. - * 0 if operation is successful. - * + * pci_enable_wake - enable PCI device as wakeup event source + * @dev: PCI device affected + * @state: PCI state from which device will issue wakeup events + * @enable: True to enable event generation; false to disable + * + * This enables the device as a wakeup event source, or disables it. + * When such events involves platform-specific hooks, those hooks are + * called automatically by this routine. + * + * Devices with legacy power management (no standard PCI PM capabilities) + * always require such platform hooks. Depending on the platform, devices + * supporting the standard PCI PME# signal may require such platform hooks; + * they always update bits in config space to allow PME# generation. + * + * -EIO is returned if the device can't ever be a wakeup event source. + * -EINVAL is returned if the device can't generate wakeup events from + * the specified PCI state. Returns zero if the operation is successful. */ int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable) { int pm; + int status; u16 value; + /* Note that drivers should verify device_may_wakeup(&dev->dev) + * before calling this function. Platform code should report + * errors when drivers try to enable wakeup on devices that + * can't issue wakeups, or on which wakeups were disabled by + * userspace updating the /sys/devices.../power/wakeup file. + */ + + if (platform_enable_wakeup) { + status = platform_enable_wakeup(&dev->dev, enable); + if (status) + return status; + } else + status = -EIO; + /* find PCI PM capability in list */ pm = pci_find_capability(dev, PCI_CAP_ID_PM); - /* If device doesn't support PM Capabilities, but request is to disable - * wake events, it's a nop; otherwise fail */ - if (!pm) - return enable ? -EIO : 0; + /* If device doesn't support PM Capabilities, but caller wants to + * disable wake events, it's a NOP. Otherwise fail unless the + * platform hooks handled this legacy device already. + */ + if (!pm) + return enable ? status : 0; /* Check device's ability to generate PME# */ pci_read_config_word(dev,pm+PCI_PM_PMC,&value); @@ -924,8 +946,11 @@ int pci_enable_wake(struct pci_dev *dev, value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */ /* Check if it can generate PME# from requested state. */ - if (!value || !(value & (1 << state))) + if (!value || !(value & (1 << state))) { + if (enable && platform_enable_wakeup) + (void) platform_enable_wakeup(&dev->dev, 0); return enable ? -EINVAL : 0; + } pci_read_config_word(dev, pm + PCI_PM_CTRL, &value); @@ -936,7 +961,7 @@ int pci_enable_wake(struct pci_dev *dev, value &= ~PCI_PM_CTRL_PME_ENABLE; pci_write_config_word(dev, pm + PCI_PM_CTRL, value); - + return 0; } _______________________________________________ linux-pm mailing list [EMAIL PROTECTED] https://lists.linux-foundation.org/mailman/listinfo/linux-pm ----- End forwarded message ----- -- Jordan Crouse Senior Linux Engineer Advanced Micro Devices, Inc. <www.amd.com/embeddedprocessors> _______________________________________________ Devel mailing list [email protected] http://mailman.laptop.org/mailman/listinfo/devel
