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authorBjorn Helgaas <bhelgaas@google.com>2013-08-15 22:41:33 +0200
committerBjorn Helgaas <bhelgaas@google.com>2013-08-15 22:41:33 +0200
commit7d8c4a2c5ae6d76f1142fb052d698b3c40ce518c (patch)
treee5f4d7779bd2e6b4e9ccc3e73d5c40bb537513e8
parentMerge branch 'pci/vipul-chelsio-reset-v2' into next (diff)
parentPCI: Add pci_probe_reset_slot() and pci_probe_reset_bus() (diff)
downloadlinux-7d8c4a2c5ae6d76f1142fb052d698b3c40ce518c.tar.xz
linux-7d8c4a2c5ae6d76f1142fb052d698b3c40ce518c.zip
Merge branch 'pci/aw-reset-v5' into next
* pci/aw-reset-v5: PCI: Add pci_probe_reset_slot() and pci_probe_reset_bus() PCI: Remove aer_do_secondary_bus_reset() PCI: Tune secondary bus reset timing PCI: Wake-up devices before saving config space for reset PCI: Add pci_reset_slot() and pci_reset_bus() PCI: Split out pci_dev lock/unlock and save/restore PCI: Add slot reset option to pci_dev_reset() PCI: pciehp: Add reset_slot() method PCI: Add hotplug_slot_ops.reset_slot() PCI: Add pci_reset_bridge_secondary_bus()
-rw-r--r--drivers/pci/hotplug/pciehp.h1
-rw-r--r--drivers/pci/hotplug/pciehp_core.c12
-rw-r--r--drivers/pci/hotplug/pciehp_hpc.c31
-rw-r--r--drivers/pci/pci.c373
-rw-r--r--drivers/pci/pcie/aer/aerdrv.c2
-rw-r--r--drivers/pci/pcie/aer/aerdrv.h1
-rw-r--r--drivers/pci/pcie/aer/aerdrv_core.c35
-rw-r--r--include/linux/pci.h5
-rw-r--r--include/linux/pci_hotplug.h4
9 files changed, 402 insertions, 62 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 7fb326983ed6..541bbe6d5343 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -155,6 +155,7 @@ void pciehp_green_led_off(struct slot *slot);
void pciehp_green_led_blink(struct slot *slot);
int pciehp_check_link_status(struct controller *ctrl);
void pciehp_release_ctrl(struct controller *ctrl);
+int pciehp_reset_slot(struct slot *slot, int probe);
static inline const char *slot_name(struct slot *slot)
{
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 7d72c5e2eba9..f4a18f51a29c 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -69,6 +69,7 @@ static int get_power_status (struct hotplug_slot *slot, u8 *value);
static int get_attention_status (struct hotplug_slot *slot, u8 *value);
static int get_latch_status (struct hotplug_slot *slot, u8 *value);
static int get_adapter_status (struct hotplug_slot *slot, u8 *value);
+static int reset_slot (struct hotplug_slot *slot, int probe);
/**
* release_slot - free up the memory used by a slot
@@ -111,6 +112,7 @@ static int init_slot(struct controller *ctrl)
ops->disable_slot = disable_slot;
ops->get_power_status = get_power_status;
ops->get_adapter_status = get_adapter_status;
+ ops->reset_slot = reset_slot;
if (MRL_SENS(ctrl))
ops->get_latch_status = get_latch_status;
if (ATTN_LED(ctrl)) {
@@ -223,6 +225,16 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
return pciehp_get_adapter_status(slot, value);
}
+static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
+{
+ struct slot *slot = hotplug_slot->private;
+
+ ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
+ __func__, slot_name(slot));
+
+ return pciehp_reset_slot(slot, probe);
+}
+
static int pciehp_probe(struct pcie_device *dev)
{
int rc;
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index b2255736ac81..51f56ef4ab6f 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -749,6 +749,37 @@ static void pcie_disable_notification(struct controller *ctrl)
ctrl_warn(ctrl, "Cannot disable software notification\n");
}
+/*
+ * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
+ * bus reset of the bridge, but if the slot supports surprise removal we need
+ * to disable presence detection around the bus reset and clear any spurious
+ * events after.
+ */
+int pciehp_reset_slot(struct slot *slot, int probe)
+{
+ struct controller *ctrl = slot->ctrl;
+
+ if (probe)
+ return 0;
+
+ if (HP_SUPR_RM(ctrl)) {
+ pcie_write_cmd(ctrl, 0, PCI_EXP_SLTCTL_PDCE);
+ if (pciehp_poll_mode)
+ del_timer_sync(&ctrl->poll_timer);
+ }
+
+ pci_reset_bridge_secondary_bus(ctrl->pcie->port);
+
+ if (HP_SUPR_RM(ctrl)) {
+ pciehp_writew(ctrl, PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDC);
+ pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PDCE, PCI_EXP_SLTCTL_PDCE);
+ if (pciehp_poll_mode)
+ int_poll_timeout(ctrl->poll_timer.data);
+ }
+
+ return 0;
+}
+
int pcie_init_notification(struct controller *ctrl)
{
if (pciehp_request_irq(ctrl))
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7d6ce2ec04ec..10e3c4e15178 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -22,6 +22,7 @@
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/pm_runtime.h>
+#include <linux/pci_hotplug.h>
#include <asm-generic/pci-bridge.h>
#include <asm/setup.h>
#include "pci.h"
@@ -3288,9 +3289,42 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)
return 0;
}
-static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
+/**
+ * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
+ * @dev: Bridge device
+ *
+ * Use the bridge control register to assert reset on the secondary bus.
+ * Devices on the secondary bus are left in power-on state.
+ */
+void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
{
u16 ctrl;
+
+ pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
+ ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
+ pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
+ /*
+ * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double
+ * this to 2ms to ensure that we meet the minium requirement.
+ */
+ msleep(2);
+
+ ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
+ pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
+
+ /*
+ * Trhfa for conventional PCI is 2^25 clock cycles.
+ * Assuming a minimum 33MHz clock this results in a 1s
+ * delay before we can consider subordinate devices to
+ * be re-initialized. PCIe has some ways to shorten this,
+ * but we don't make use of them yet.
+ */
+ ssleep(1);
+}
+EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
+
+static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
+{
struct pci_dev *pdev;
if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
@@ -3303,18 +3337,40 @@ static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
if (probe)
return 0;
- pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
- ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
- pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
- msleep(100);
-
- ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
- pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
- msleep(100);
+ pci_reset_bridge_secondary_bus(dev->bus->self);
return 0;
}
+static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
+{
+ int rc = -ENOTTY;
+
+ if (!hotplug || !try_module_get(hotplug->ops->owner))
+ return rc;
+
+ if (hotplug->ops->reset_slot)
+ rc = hotplug->ops->reset_slot(hotplug, probe);
+
+ module_put(hotplug->ops->owner);
+
+ return rc;
+}
+
+static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
+{
+ struct pci_dev *pdev;
+
+ if (dev->subordinate || !dev->slot)
+ return -ENOTTY;
+
+ list_for_each_entry(pdev, &dev->bus->devices, bus_list)
+ if (pdev != dev && pdev->slot == dev->slot)
+ return -ENOTTY;
+
+ return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
+}
+
static int __pci_dev_reset(struct pci_dev *dev, int probe)
{
int rc;
@@ -3337,27 +3393,65 @@ static int __pci_dev_reset(struct pci_dev *dev, int probe)
if (rc != -ENOTTY)
goto done;
+ rc = pci_dev_reset_slot_function(dev, probe);
+ if (rc != -ENOTTY)
+ goto done;
+
rc = pci_parent_bus_reset(dev, probe);
done:
return rc;
}
+static void pci_dev_lock(struct pci_dev *dev)
+{
+ pci_cfg_access_lock(dev);
+ /* block PM suspend, driver probe, etc. */
+ device_lock(&dev->dev);
+}
+
+static void pci_dev_unlock(struct pci_dev *dev)
+{
+ device_unlock(&dev->dev);
+ pci_cfg_access_unlock(dev);
+}
+
+static void pci_dev_save_and_disable(struct pci_dev *dev)
+{
+ /*
+ * Wake-up device prior to save. PM registers default to D0 after
+ * reset and a simple register restore doesn't reliably return
+ * to a non-D0 state anyway.
+ */
+ pci_set_power_state(dev, PCI_D0);
+
+ pci_save_state(dev);
+ /*
+ * Disable the device by clearing the Command register, except for
+ * INTx-disable which is set. This not only disables MMIO and I/O port
+ * BARs, but also prevents the device from being Bus Master, preventing
+ * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3
+ * compliant devices, INTx-disable prevents legacy interrupts.
+ */
+ pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
+}
+
+static void pci_dev_restore(struct pci_dev *dev)
+{
+ pci_restore_state(dev);
+}
+
static int pci_dev_reset(struct pci_dev *dev, int probe)
{
int rc;
- if (!probe) {
- pci_cfg_access_lock(dev);
- /* block PM suspend, driver probe, etc. */
- device_lock(&dev->dev);
- }
+ if (!probe)
+ pci_dev_lock(dev);
rc = __pci_dev_reset(dev, probe);
- if (!probe) {
- device_unlock(&dev->dev);
- pci_cfg_access_unlock(dev);
- }
+ if (!probe)
+ pci_dev_unlock(dev);
+
return rc;
}
/**
@@ -3448,22 +3542,249 @@ int pci_reset_function(struct pci_dev *dev)
if (rc)
return rc;
- pci_save_state(dev);
-
- /*
- * both INTx and MSI are disabled after the Interrupt Disable bit
- * is set and the Bus Master bit is cleared.
- */
- pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
+ pci_dev_save_and_disable(dev);
rc = pci_dev_reset(dev, 0);
- pci_restore_state(dev);
+ pci_dev_restore(dev);
return rc;
}
EXPORT_SYMBOL_GPL(pci_reset_function);
+/* Lock devices from the top of the tree down */
+static void pci_bus_lock(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ pci_dev_lock(dev);
+ if (dev->subordinate)
+ pci_bus_lock(dev->subordinate);
+ }
+}
+
+/* Unlock devices from the bottom of the tree up */
+static void pci_bus_unlock(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ if (dev->subordinate)
+ pci_bus_unlock(dev->subordinate);
+ pci_dev_unlock(dev);
+ }
+}
+
+/* Lock devices from the top of the tree down */
+static void pci_slot_lock(struct pci_slot *slot)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &slot->bus->devices, bus_list) {
+ if (!dev->slot || dev->slot != slot)
+ continue;
+ pci_dev_lock(dev);
+ if (dev->subordinate)
+ pci_bus_lock(dev->subordinate);
+ }
+}
+
+/* Unlock devices from the bottom of the tree up */
+static void pci_slot_unlock(struct pci_slot *slot)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &slot->bus->devices, bus_list) {
+ if (!dev->slot || dev->slot != slot)
+ continue;
+ if (dev->subordinate)
+ pci_bus_unlock(dev->subordinate);
+ pci_dev_unlock(dev);
+ }
+}
+
+/* Save and disable devices from the top of the tree down */
+static void pci_bus_save_and_disable(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ pci_dev_save_and_disable(dev);
+ if (dev->subordinate)
+ pci_bus_save_and_disable(dev->subordinate);
+ }
+}
+
+/*
+ * Restore devices from top of the tree down - parent bridges need to be
+ * restored before we can get to subordinate devices.
+ */
+static void pci_bus_restore(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ pci_dev_restore(dev);
+ if (dev->subordinate)
+ pci_bus_restore(dev->subordinate);
+ }
+}
+
+/* Save and disable devices from the top of the tree down */
+static void pci_slot_save_and_disable(struct pci_slot *slot)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &slot->bus->devices, bus_list) {
+ if (!dev->slot || dev->slot != slot)
+ continue;
+ pci_dev_save_and_disable(dev);
+ if (dev->subordinate)
+ pci_bus_save_and_disable(dev->subordinate);
+ }
+}
+
+/*
+ * Restore devices from top of the tree down - parent bridges need to be
+ * restored before we can get to subordinate devices.
+ */
+static void pci_slot_restore(struct pci_slot *slot)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &slot->bus->devices, bus_list) {
+ if (!dev->slot || dev->slot != slot)
+ continue;
+ pci_dev_restore(dev);
+ if (dev->subordinate)
+ pci_bus_restore(dev->subordinate);
+ }
+}
+
+static int pci_slot_reset(struct pci_slot *slot, int probe)
+{
+ int rc;
+
+ if (!slot)
+ return -ENOTTY;
+
+ if (!probe)
+ pci_slot_lock(slot);
+
+ might_sleep();
+
+ rc = pci_reset_hotplug_slot(slot->hotplug, probe);
+
+ if (!probe)
+ pci_slot_unlock(slot);
+
+ return rc;
+}
+
+/**
+ * pci_probe_reset_slot - probe whether a PCI slot can be reset
+ * @slot: PCI slot to probe
+ *
+ * Return 0 if slot can be reset, negative if a slot reset is not supported.
+ */
+int pci_probe_reset_slot(struct pci_slot *slot)
+{
+ return pci_slot_reset(slot, 1);
+}
+EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
+
+/**
+ * pci_reset_slot - reset a PCI slot
+ * @slot: PCI slot to reset
+ *
+ * A PCI bus may host multiple slots, each slot may support a reset mechanism
+ * independent of other slots. For instance, some slots may support slot power
+ * control. In the case of a 1:1 bus to slot architecture, this function may
+ * wrap the bus reset to avoid spurious slot related events such as hotplug.
+ * Generally a slot reset should be attempted before a bus reset. All of the
+ * function of the slot and any subordinate buses behind the slot are reset
+ * through this function. PCI config space of all devices in the slot and
+ * behind the slot is saved before and restored after reset.
+ *
+ * Return 0 on success, non-zero on error.
+ */
+int pci_reset_slot(struct pci_slot *slot)
+{
+ int rc;
+
+ rc = pci_slot_reset(slot, 1);
+ if (rc)
+ return rc;
+
+ pci_slot_save_and_disable(slot);
+
+ rc = pci_slot_reset(slot, 0);
+
+ pci_slot_restore(slot);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_reset_slot);
+
+static int pci_bus_reset(struct pci_bus *bus, int probe)
+{
+ if (!bus->self)
+ return -ENOTTY;
+
+ if (probe)
+ return 0;
+
+ pci_bus_lock(bus);
+
+ might_sleep();
+
+ pci_reset_bridge_secondary_bus(bus->self);
+
+ pci_bus_unlock(bus);
+
+ return 0;
+}
+
+/**
+ * pci_probe_reset_bus - probe whether a PCI bus can be reset
+ * @bus: PCI bus to probe
+ *
+ * Return 0 if bus can be reset, negative if a bus reset is not supported.
+ */
+int pci_probe_reset_bus(struct pci_bus *bus)
+{
+ return pci_bus_reset(bus, 1);
+}
+EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
+
+/**
+ * pci_reset_bus - reset a PCI bus
+ * @bus: top level PCI bus to reset
+ *
+ * Do a bus reset on the given bus and any subordinate buses, saving
+ * and restoring state of all devices.
+ *
+ * Return 0 on success, non-zero on error.
+ */
+int pci_reset_bus(struct pci_bus *bus)
+{
+ int rc;
+
+ rc = pci_bus_reset(bus, 1);
+ if (rc)
+ return rc;
+
+ pci_bus_save_and_disable(bus);
+
+ rc = pci_bus_reset(bus, 0);
+
+ pci_bus_restore(bus);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_reset_bus);
+
/**
* pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
* @dev: PCI device to query
diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c
index 76ef634caf6f..0bf82a20a0fb 100644
--- a/drivers/pci/pcie/aer/aerdrv.c
+++ b/drivers/pci/pcie/aer/aerdrv.c
@@ -352,7 +352,7 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
- aer_do_secondary_bus_reset(dev);
+ pci_reset_bridge_secondary_bus(dev);
dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");
/* Clear Root Error Status */
diff --git a/drivers/pci/pcie/aer/aerdrv.h b/drivers/pci/pcie/aer/aerdrv.h
index 90ea3e88041f..84420b7c9456 100644
--- a/drivers/pci/pcie/aer/aerdrv.h
+++ b/drivers/pci/pcie/aer/aerdrv.h
@@ -106,7 +106,6 @@ static inline pci_ers_result_t merge_result(enum pci_ers_result orig,
}
extern struct bus_type pcie_port_bus_type;
-void aer_do_secondary_bus_reset(struct pci_dev *dev);
int aer_init(struct pcie_device *dev);
void aer_isr(struct work_struct *work);
void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
index 8b68ae59b7b6..85ca36f2136d 100644
--- a/drivers/pci/pcie/aer/aerdrv_core.c
+++ b/drivers/pci/pcie/aer/aerdrv_core.c
@@ -367,39 +367,6 @@ static pci_ers_result_t broadcast_error_message(struct pci_dev *dev,
}
/**
- * aer_do_secondary_bus_reset - perform secondary bus reset
- * @dev: pointer to bridge's pci_dev data structure
- *
- * Invoked when performing link reset at Root Port or Downstream Port.
- */
-void aer_do_secondary_bus_reset(struct pci_dev *dev)
-{
- u16 p2p_ctrl;
-
- /* Assert Secondary Bus Reset */
- pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
- p2p_ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
- pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
-
- /*
- * we should send hot reset message for 2ms to allow it time to
- * propagate to all downstream ports
- */
- msleep(2);
-
- /* De-assert Secondary Bus Reset */
- p2p_ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
- pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
-
- /*
- * System software must wait for at least 100ms from the end
- * of a reset of one or more device before it is permitted
- * to issue Configuration Requests to those devices.
- */
- msleep(200);
-}
-
-/**
* default_reset_link - default reset function
* @dev: pointer to pci_dev data structure
*
@@ -408,7 +375,7 @@ void aer_do_secondary_bus_reset(struct pci_dev *dev)
*/
static pci_ers_result_t default_reset_link(struct pci_dev *dev)
{
- aer_do_secondary_bus_reset(dev);
+ pci_reset_bridge_secondary_bus(dev);
dev_printk(KERN_DEBUG, &dev->dev, "downstream link has been reset\n");
return PCI_ERS_RESULT_RECOVERED;
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e6470016c718..408f047ad929 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -925,6 +925,11 @@ int pcie_set_mps(struct pci_dev *dev, int mps);
int __pci_reset_function(struct pci_dev *dev);
int __pci_reset_function_locked(struct pci_dev *dev);
int pci_reset_function(struct pci_dev *dev);
+int pci_probe_reset_slot(struct pci_slot *slot);
+int pci_reset_slot(struct pci_slot *slot);
+int pci_probe_reset_bus(struct pci_bus *bus);
+int pci_reset_bus(struct pci_bus *bus);
+void pci_reset_bridge_secondary_bus(struct pci_dev *dev);
void pci_update_resource(struct pci_dev *dev, int resno);
int __must_check pci_assign_resource(struct pci_dev *dev, int i);
int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align);
diff --git a/include/linux/pci_hotplug.h b/include/linux/pci_hotplug.h
index 8db71dcd6337..bd32109e607e 100644
--- a/include/linux/pci_hotplug.h
+++ b/include/linux/pci_hotplug.h
@@ -63,6 +63,9 @@ enum pcie_link_width {
* @get_adapter_status: Called to get see if an adapter is present in the slot or not.
* If this field is NULL, the value passed in the struct hotplug_slot_info
* will be used when this value is requested by a user.
+ * @reset_slot: Optional interface to allow override of a bus reset for the
+ * slot for cases where a secondary bus reset can result in spurious
+ * hotplug events or where a slot can be reset independent of the bus.
*
* The table of function pointers that is passed to the hotplug pci core by a
* hotplug pci driver. These functions are called by the hotplug pci core when
@@ -80,6 +83,7 @@ struct hotplug_slot_ops {
int (*get_attention_status) (struct hotplug_slot *slot, u8 *value);
int (*get_latch_status) (struct hotplug_slot *slot, u8 *value);
int (*get_adapter_status) (struct hotplug_slot *slot, u8 *value);
+ int (*reset_slot) (struct hotplug_slot *slot, int probe);
};
/**