From dcf443b5813074031a45b05ad9c57da98bcae329 Mon Sep 17 00:00:00 2001 From: Alan Jenkins Date: Fri, 28 Aug 2009 12:56:33 +0000 Subject: [PATCH] eeepc-laptop: use a mutex to serialize pci hotplug (resume vs. notify) Commit d0265f0 "eeepc-laptop: fix hot-unplug on resume" used a workqueue to protect pci hotplug against multiple simultaneous calls during resume. It seems to work, but a mutex would be more appropriate. This is in preparation to fix the potential pci hotplug race on unload. Signed-off-by: Alan Jenkins Signed-off-by: Corentin Chary Signed-off-by: Len Brown --- drivers/platform/x86/eeepc-laptop.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c index 69d73ed2c8ab..179010386981 100644 --- a/drivers/platform/x86/eeepc-laptop.c +++ b/drivers/platform/x86/eeepc-laptop.c @@ -143,7 +143,7 @@ struct eeepc_hotk { struct rfkill *bluetooth_rfkill; struct rfkill *wwan3g_rfkill; struct hotplug_slot *hotplug_slot; - struct work_struct hotplug_work; + struct mutex hotplug_lock; }; /* The actual device the driver binds to */ @@ -661,7 +661,7 @@ static int eeepc_get_adapter_status(struct hotplug_slot *hotplug_slot, return 0; } -static void eeepc_hotplug_work(struct work_struct *work) +static void eeepc_rfkill_hotplug(void) { struct pci_dev *dev; struct pci_bus *bus; @@ -669,13 +669,15 @@ static void eeepc_hotplug_work(struct work_struct *work) rfkill_set_sw_state(ehotk->wlan_rfkill, blocked); + mutex_lock(&ehotk->hotplug_lock); + if (ehotk->hotplug_slot == NULL) - return; + goto out_unlock; bus = pci_find_bus(0, 1); if (!bus) { pr_warning("Unable to find PCI bus 1?\n"); - return; + goto out_unlock; } if (!blocked) { @@ -683,7 +685,7 @@ static void eeepc_hotplug_work(struct work_struct *work) if (dev) { /* Device already present */ pci_dev_put(dev); - return; + goto out_unlock; } dev = pci_scan_single_device(bus, 0); if (dev) { @@ -698,6 +700,9 @@ static void eeepc_hotplug_work(struct work_struct *work) pci_dev_put(dev); } } + +out_unlock: + mutex_unlock(&ehotk->hotplug_lock); } static void eeepc_rfkill_notify(acpi_handle handle, u32 event, void *data) @@ -705,7 +710,7 @@ static void eeepc_rfkill_notify(acpi_handle handle, u32 event, void *data) if (event != ACPI_NOTIFY_BUS_CHECK) return; - schedule_work(&ehotk->hotplug_work); + eeepc_rfkill_hotplug(); } static void eeepc_hotk_notify(struct acpi_device *device, u32 event) @@ -896,7 +901,7 @@ static int eeepc_hotk_resume(struct acpi_device *device) rfkill_set_sw_state(ehotk->wlan_rfkill, wlan != 1); - schedule_work(&ehotk->hotplug_work); + eeepc_rfkill_hotplug(); } if (ehotk->bluetooth_rfkill) @@ -1097,7 +1102,7 @@ static int eeepc_rfkill_init(struct device *dev) { int result = 0; - INIT_WORK(&ehotk->hotplug_work, eeepc_hotplug_work); + mutex_init(&ehotk->hotplug_lock); eeepc_register_rfkill_notifier("\\_SB.PCI0.P0P6"); eeepc_register_rfkill_notifier("\\_SB.PCI0.P0P7");