diff options
| -rw-r--r-- | drivers/platform/x86/wmi.c | 71 |
1 files changed, 47 insertions, 24 deletions
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 699157ce347c..d1df1a31de00 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -25,6 +25,7 @@ #include <linux/list.h> #include <linux/module.h> #include <linux/platform_device.h> +#include <linux/rwsem.h> #include <linux/slab.h> #include <linux/sysfs.h> #include <linux/types.h> @@ -56,7 +57,6 @@ static_assert(__alignof__(struct guid_block) == 1); enum { /* wmi_block flags */ WMI_READ_TAKES_NO_ARGS, - WMI_PROBED, }; struct wmi_block { @@ -64,8 +64,10 @@ struct wmi_block { struct list_head list; struct guid_block gblock; struct acpi_device *acpi_device; + struct rw_semaphore notify_lock; /* Protects notify callback add/remove */ wmi_notify_handler handler; void *handler_data; + bool driver_ready; unsigned long flags; }; @@ -603,6 +605,8 @@ acpi_status wmi_install_notify_handler(const char *guid, return AE_ERROR; wblock = container_of(wdev, struct wmi_block, dev); + + down_write(&wblock->notify_lock); if (wblock->handler) { status = AE_ALREADY_ACQUIRED; } else { @@ -614,6 +618,7 @@ acpi_status wmi_install_notify_handler(const char *guid, status = AE_OK; } + up_write(&wblock->notify_lock); wmi_device_put(wdev); @@ -640,6 +645,8 @@ acpi_status wmi_remove_notify_handler(const char *guid) return AE_ERROR; wblock = container_of(wdev, struct wmi_block, dev); + + down_write(&wblock->notify_lock); if (!wblock->handler) { status = AE_NULL_ENTRY; } else { @@ -651,6 +658,7 @@ acpi_status wmi_remove_notify_handler(const char *guid) status = AE_OK; } + up_write(&wblock->notify_lock); wmi_device_put(wdev); @@ -896,7 +904,9 @@ static int wmi_dev_probe(struct device *dev) } } - set_bit(WMI_PROBED, &wblock->flags); + down_write(&wblock->notify_lock); + wblock->driver_ready = true; + up_write(&wblock->notify_lock); return 0; } @@ -906,7 +916,9 @@ static void wmi_dev_remove(struct device *dev) struct wmi_block *wblock = dev_to_wblock(dev); struct wmi_driver *wdriver = drv_to_wdrv(dev->driver); - clear_bit(WMI_PROBED, &wblock->flags); + down_write(&wblock->notify_lock); + wblock->driver_ready = false; + up_write(&wblock->notify_lock); if (wdriver->remove) wdriver->remove(dev_to_wdev(dev)); @@ -1019,6 +1031,8 @@ static int wmi_create_device(struct device *wmi_bus_dev, wblock->dev.setable = true; out_init: + init_rwsem(&wblock->notify_lock); + wblock->driver_ready = false; wblock->dev.dev.bus = &wmi_bus_type; wblock->dev.dev.parent = wmi_bus_dev; @@ -1191,6 +1205,26 @@ acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address, } } +static void wmi_notify_driver(struct wmi_block *wblock) +{ + struct wmi_driver *driver = drv_to_wdrv(wblock->dev.dev.driver); + struct acpi_buffer data = { ACPI_ALLOCATE_BUFFER, NULL }; + acpi_status status; + + if (!driver->no_notify_data) { + status = get_event_data(wblock, &data); + if (ACPI_FAILURE(status)) { + dev_warn(&wblock->dev.dev, "Failed to get event data\n"); + return; + } + } + + if (driver->notify) + driver->notify(&wblock->dev, data.pointer); + + kfree(data.pointer); +} + static int wmi_notify_device(struct device *dev, void *data) { struct wmi_block *wblock = dev_to_wblock(dev); @@ -1199,28 +1233,17 @@ static int wmi_notify_device(struct device *dev, void *data) if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event)) return 0; - /* If a driver is bound, then notify the driver. */ - if (test_bit(WMI_PROBED, &wblock->flags) && wblock->dev.dev.driver) { - struct wmi_driver *driver = drv_to_wdrv(wblock->dev.dev.driver); - struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL }; - acpi_status status; - - if (!driver->no_notify_data) { - status = get_event_data(wblock, &evdata); - if (ACPI_FAILURE(status)) { - dev_warn(&wblock->dev.dev, "failed to get event data\n"); - return -EIO; - } - } - - if (driver->notify) - driver->notify(&wblock->dev, evdata.pointer); - - kfree(evdata.pointer); - } else if (wblock->handler) { - /* Legacy handler */ - wblock->handler(*event, wblock->handler_data); + down_read(&wblock->notify_lock); + /* The WMI driver notify handler conflicts with the legacy WMI handler. + * Because of this the WMI driver notify handler takes precedence. + */ + if (wblock->dev.dev.driver && wblock->driver_ready) { + wmi_notify_driver(wblock); + } else { + if (wblock->handler) + wblock->handler(*event, wblock->handler_data); } + up_read(&wblock->notify_lock); acpi_bus_generate_netlink_event(wblock->acpi_device->pnp.device_class, dev_name(&wblock->dev.dev), *event, 0); |