From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH 1/12] PCI PM: Add function for checking PME status of devices Date: Wed, 6 Jan 2010 13:46:37 -0800 Message-ID: <20100106134637.7d016215__3872.10483099825$1262814470$gmane$org@jbarnes-piketon> References: <200912272057.10443.rjw@sisk.pl> <200912272059.06718.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200912272059.06718.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: Oliver@smtp1.linux-foundation.org, Linux PCI , LKML , ACPI Devel Maling List , Shaohua@smtp1.linux-foundation.org, Francois Romieu , pm list , Matthew Garrett List-Id: linux-pm@vger.kernel.org On Sun, 27 Dec 2009 20:59:06 +0100 "Rafael J. Wysocki" wrote: > From: Rafael J. Wysocki > > Add function pci_check_pme_status() that will check the PME status > bit of given device and clear it along with the PME enable bit. It > will be necessary for PCI run-time power management. > > Based on a patch from Shaohua Li > > Signed-off-by: Rafael J. Wysocki > --- > drivers/pci/pci.c | 35 +++++++++++++++++++++++++++++++++++ > drivers/pci/pci.h | 1 + > 2 files changed, 36 insertions(+) > > Index: linux-2.6/drivers/pci/pci.h > =================================================================== > --- linux-2.6.orig/drivers/pci/pci.h > +++ linux-2.6/drivers/pci/pci.h > @@ -49,6 +49,7 @@ struct pci_platform_pm_ops { > extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops); > extern void pci_update_current_state(struct pci_dev *dev, > pci_power_t state); extern void pci_disable_enabled_device(struct > pci_dev *dev); +extern bool pci_check_pme_status(struct pci_dev *dev); > extern void pci_pm_init(struct pci_dev *dev); > extern void platform_pci_wakeup_init(struct pci_dev *dev); > extern void pci_allocate_cap_save_buffers(struct pci_dev *dev); > Index: linux-2.6/drivers/pci/pci.c > =================================================================== > --- linux-2.6.orig/drivers/pci/pci.c > +++ linux-2.6/drivers/pci/pci.c > @@ -1180,6 +1180,41 @@ int pci_set_pcie_reset_state(struct pci_ > } > > /** > + * pci_check_pme_status - Check if given device has generated PME. > + * @dev: Device to check. > + * > + * Check the PME status of the device and if set, clear it and clear > PME enable > + * (if set). Return 'true' if PME status and PME enable were both > set or > + * 'false' otherwise. > + */ > +bool pci_check_pme_status(struct pci_dev *dev) > +{ > + int pmcsr_pos; > + u16 pmcsr; > + bool ret = false; > + > + if (!dev->pm_cap) > + return false; > + > + pmcsr_pos = dev->pm_cap + PCI_PM_CTRL; > + pci_read_config_word(dev, pmcsr_pos, &pmcsr); > + if (!(pmcsr & PCI_PM_CTRL_PME_STATUS)) > + return false; > + > + /* Clear PME status. */ > + pmcsr |= PCI_PM_CTRL_PME_STATUS; > + if (pmcsr & PCI_PM_CTRL_PME_ENABLE) { > + /* Disable PME to avoid interrupt flood. */ > + pmcsr &= ~PCI_PM_CTRL_PME_ENABLE; > + ret = true; > + } > + > + pci_write_config_word(dev, pmcsr_pos, pmcsr); > + > + return ret; > +} > + > +/** > * pci_pme_capable - check the capability of PCI device to generate > PME# > * @dev: PCI device to handle. > * @state: PCI state from which device will issue PME#. > > Looks fine to me; would be especially nice if we could somehow communicate that this function was ack'ing any outstanding PME event in the function name too. -- Jesse Barnes, Intel Open Source Technology Center