From 711d57796f5ce2d02d6e62c9034afbb16aedda31 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 27 Jul 2009 23:37:48 +0300 Subject: PCI: expose function reset capability in sysfs Some devices allow an individual function to be reset without affecting other functions in the same device: that's what pci_reset_function does. For devices that have this support, expose reset attribite in sysfs. This is useful e.g. for virtualization, where a qemu userspace process wants to reset the device when the guest is reset, to emulate machine reboot as closely as possible. Acked-by: Greg Kroah-Hartman Signed-off-by: Michael S. Tsirkin Signed-off-by: Jesse Barnes --- drivers/pci/pci-sysfs.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'drivers/pci/pci-sysfs.c') diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 85ebd02a64a7..0f6382f090ee 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -916,6 +916,24 @@ int __attribute__ ((weak)) pcibios_add_platform_entries(struct pci_dev *dev) return 0; } +static ssize_t reset_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct pci_dev *pdev = to_pci_dev(dev); + unsigned long val; + ssize_t result = strict_strtoul(buf, 0, &val); + + if (result < 0) + return result; + + if (val != 1) + return -EINVAL; + return pci_reset_function(pdev); +} + +static struct device_attribute reset_attr = __ATTR(reset, 0200, NULL, reset_store); + static int pci_create_capabilities_sysfs(struct pci_dev *dev) { int retval; @@ -943,7 +961,22 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev) /* Active State Power Management */ pcie_aspm_create_sysfs_dev_files(dev); + if (!pci_probe_reset_function(dev)) { + retval = device_create_file(&dev->dev, &reset_attr); + if (retval) + goto error; + dev->reset_fn = 1; + } return 0; + +error: + pcie_aspm_remove_sysfs_dev_files(dev); + if (dev->vpd && dev->vpd->attr) { + sysfs_remove_bin_file(&dev->dev.kobj, dev->vpd->attr); + kfree(dev->vpd->attr); + } + + return retval; } int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev) @@ -1037,6 +1070,10 @@ static void pci_remove_capabilities_sysfs(struct pci_dev *dev) } pcie_aspm_remove_sysfs_dev_files(dev); + if (dev->reset_fn) { + device_remove_file(&dev->dev, &reset_attr); + dev->reset_fn = 0; + } } /** -- cgit v1.2.3