From: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
Various pieces of hardware (such as the Acer Aspire One and Asus EEE) use
PCIE hotplug to change the state of devices in response to events such as
the removal of SD cards or disabling the wireless radio. However, they do
not provide firmware support for this. As a consequence pciehp will
refuse to load and various things break.
The existing workaround has been to use the pciehp_force option. This is
undesirable as there is little guarantee that manipulating the power file
in the slot directory will actually result in anything happening, leading
to potential user confusion and hardware damage. This patch adds a new
option, pciehp_passive. In this configuration pciehp will listen for
events and notify the PCI core appropriately. However, it will not
provide any user controllable sysfs attributes and so the risk of
confusion or damage is averted. Any system slots that do have firmware
support will continue to provide full functionality.
[akpm@xxxxxxxxxxxxxxxxxxxx: coding-style fixes]
Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>
Cc: Kristen Carlson Accardi <kristen.c.accardi@xxxxxxxxx>
Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/pci/hotplug/pciehp_core.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff -puN drivers/pci/hotplug/pciehp_core.c~pcie-add-option-to-passively-listen-for-pcie-hotplug-events drivers/pci/hotplug/pciehp_core.c
--- a/drivers/pci/hotplug/pciehp_core.c~pcie-add-option-to-passively-listen-for-pcie-hotplug-events
+++ a/drivers/pci/hotplug/pciehp_core.c
@@ -41,6 +41,7 @@ int pciehp_debug;
int pciehp_poll_mode;
int pciehp_poll_time;
int pciehp_force;
+int pciehp_passive;
struct workqueue_struct *pciehp_wq;
#define DRIVER_VERSION "0.4"
@@ -55,10 +56,12 @@ module_param(pciehp_debug, bool, 0644);
module_param(pciehp_poll_mode, bool, 0644);
module_param(pciehp_poll_time, int, 0644);
module_param(pciehp_force, bool, 0644);
+module_param(pciehp_passive, bool, 0644);
MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if _OSC and OSHP are missing");
+MODULE_PARM_DESC(pciehp_passive, "Listen for pciehp events, even if _OSC and OSHP are missing");
#define PCIE_MODULE_NAME "pciehp"
@@ -85,6 +88,13 @@ static struct hotplug_slot_ops pciehp_ho
.get_cur_bus_speed = get_cur_bus_speed,
};
+static struct hotplug_slot_ops pciehp_passive_hotplug_slot_ops = {
+ .owner = THIS_MODULE,
+ .get_adapter_status = get_adapter_status,
+ .get_max_bus_speed = get_max_bus_speed,
+ .get_cur_bus_speed = get_cur_bus_speed,
+};
+
/*
* Check the status of the Electro Mechanical Interlock (EMI)
*/
@@ -212,7 +222,11 @@ static int init_slots(struct controller
hotplug_slot->info = info;
hotplug_slot->private = slot;
hotplug_slot->release = &release_slot;
- hotplug_slot->ops = &pciehp_hotplug_slot_ops;
+ if (pciehp_passive &&
+ pciehp_get_hp_hw_control_from_firmware(ctrl->pci_dev))
+ hotplug_slot->ops = &pciehp_passive_hotplug_slot_ops;
+ else
+ hotplug_slot->ops = &pciehp_hotplug_slot_ops;
slot->hotplug_slot = hotplug_slot;
snprintf(name, SLOT_NAME_SIZE, "%u", slot->number);
@@ -407,7 +421,7 @@ static int pciehp_probe(struct pcie_devi
u8 value;
struct pci_dev *pdev = dev->port;
- if (pciehp_force)
+ if (pciehp_force || pciehp_passive)
dev_info(&dev->device,
"Bypassing BIOS check for pciehp use on %s\n",
pci_name(pdev));
@@ -435,7 +449,7 @@ static int pciehp_probe(struct pcie_devi
t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
t_slot->hpc_ops->get_adapter_status(t_slot, &value); /* Check if slot is occupied */
- if (value && pciehp_force) {
+ if (value && (pciehp_force || pciehp_passive)) {
rc = pciehp_enable_slot(t_slot);
if (rc) /* -ENODEV: shouldn't happen, but deal with it */
value = 0;
@@ -474,7 +488,7 @@ static int pciehp_suspend (struct pcie_d
static int pciehp_resume (struct pcie_device *dev)
{
dev_info(&dev->device, "%s ENTRY\n", __func__);
- if (pciehp_force) {
+ if (pciehp_force || pciehp_passive) {
struct controller *ctrl = get_service_data(dev);
struct slot *t_slot;
u8 status;
_
--
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