From 738a6396c223b486304dda778119dbbca563f019 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Fri, 20 Mar 2009 14:56:41 -0600 Subject: [PATCH] PCI: Introduce /sys/bus/pci/devices/.../rescan This interface allows the user to force a rescan of the device's parent bus and all subordinate buses, and rediscover devices removed earlier from this part of the device tree. Cc: Trent Piepho Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 10 ++++++++++ drivers/pci/pci-sysfs.c | 19 +++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index daa791a9e85e..97ad190e13af 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -74,6 +74,16 @@ Description: hot-remove the PCI device and any of its children. Depends on CONFIG_HOTPLUG. +What: /sys/bus/pci/devices/.../rescan +Date: January 2009 +Contact: Linux PCI developers +Description: + Writing a non-zero value to this attribute will + force a rescan of the device's parent bus and all + child buses, and re-discover devices removed earlier + from this part of the device tree. + Depends on CONFIG_HOTPLUG. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index e16990ecc024..e9a8706a6401 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -244,6 +244,24 @@ struct bus_attribute pci_bus_attrs[] = { __ATTR_NULL }; +static ssize_t +dev_rescan_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned long val; + struct pci_dev *pdev = to_pci_dev(dev); + + if (strict_strtoul(buf, 0, &val) < 0) + return -EINVAL; + + if (val) { + mutex_lock(&pci_remove_rescan_mutex); + pci_rescan_bus(pdev->bus); + mutex_unlock(&pci_remove_rescan_mutex); + } + return count; +} + static void remove_callback(struct device *dev) { struct pci_dev *pdev = to_pci_dev(dev); @@ -298,6 +316,7 @@ struct device_attribute pci_dev_attrs[] = { __ATTR(msi_bus, 0644, msi_bus_show, msi_bus_store), #ifdef CONFIG_HOTPLUG __ATTR(remove, (S_IWUSR|S_IWGRP), NULL, remove_store), + __ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, dev_rescan_store), #endif __ATTR_NULL, }; -- GitLab