diff options
Diffstat (limited to 'drivers/platform/x86/wmi.c')
| -rw-r--r-- | drivers/platform/x86/wmi.c | 186 |
1 files changed, 116 insertions, 70 deletions
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 646370bd6b03..4e86a422f05f 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -20,6 +20,7 @@ #include <linux/bits.h> #include <linux/build_bug.h> #include <linux/device.h> +#include <linux/idr.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> @@ -74,6 +75,8 @@ struct wmi_guid_count_context { int count; }; +static DEFINE_IDA(wmi_ida); + /* * If the GUID data block is marked as expensive, we must enable and * explicitily disable data collection. @@ -123,24 +126,6 @@ static const void *find_guid_context(struct wmi_block *wblock, return NULL; } -static acpi_status wmi_method_enable(struct wmi_block *wblock, bool enable) -{ - struct guid_block *block; - char method[5]; - acpi_status status; - acpi_handle handle; - - block = &wblock->gblock; - handle = wblock->acpi_device->handle; - - snprintf(method, 5, "WE%02X", block->notify_id); - status = acpi_execute_simple_method(handle, method, enable); - if (status == AE_NOT_FOUND) - return AE_OK; - - return status; -} - #define WMI_ACPI_METHOD_NAME_SIZE 5 static inline void get_acpi_method_name(const struct wmi_block *wblock, @@ -184,6 +169,50 @@ static int wmidev_match_guid(struct device *dev, const void *data) static const struct bus_type wmi_bus_type; +static const struct device_type wmi_type_event; + +static const struct device_type wmi_type_method; + +static int wmi_device_enable(struct wmi_device *wdev, bool enable) +{ + struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); + char method[WMI_ACPI_METHOD_NAME_SIZE]; + acpi_handle handle; + acpi_status status; + + if (wblock->dev.dev.type == &wmi_type_method) + return 0; + + if (wblock->dev.dev.type == &wmi_type_event) { + /* + * Windows always enables/disables WMI events, even when they are + * not marked as being expensive. We follow this behavior for + * compatibility reasons. + */ + snprintf(method, sizeof(method), "WE%02X", wblock->gblock.notify_id); + } else { + if (!(wblock->gblock.flags & ACPI_WMI_EXPENSIVE)) + return 0; + + get_acpi_method_name(wblock, 'C', method); + } + + /* + * Not all WMI devices marked as expensive actually implement the + * necessary ACPI method. Ignore this missing ACPI method to match + * the behaviour of the Windows driver. + */ + status = acpi_get_handle(wblock->acpi_device->handle, method, &handle); + if (ACPI_FAILURE(status)) + return 0; + + status = acpi_execute_simple_method(handle, NULL, enable); + if (ACPI_FAILURE(status)) + return -EIO; + + return 0; +} + static struct wmi_device *wmi_find_device_by_guid(const char *guid_string) { struct device *dev; @@ -337,10 +366,8 @@ static acpi_status __query_block(struct wmi_block *wblock, u8 instance, { struct guid_block *block; acpi_handle handle; - acpi_status status, wc_status = AE_ERROR; struct acpi_object_list input; union acpi_object wq_params[1]; - char wc_method[WMI_ACPI_METHOD_NAME_SIZE]; char method[WMI_ACPI_METHOD_NAME_SIZE]; if (!out) @@ -364,40 +391,9 @@ static acpi_status __query_block(struct wmi_block *wblock, u8 instance, if (instance == 0 && test_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags)) input.count = 0; - /* - * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to - * enable collection. - */ - if (block->flags & ACPI_WMI_EXPENSIVE) { - get_acpi_method_name(wblock, 'C', wc_method); - - /* - * Some GUIDs break the specification by declaring themselves - * expensive, but have no corresponding WCxx method. So we - * should not fail if this happens. - */ - wc_status = acpi_execute_simple_method(handle, wc_method, 1); - } - get_acpi_method_name(wblock, 'Q', method); - status = acpi_evaluate_object(handle, method, &input, out); - /* - * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if - * the WQxx method failed - we should disable collection anyway. - */ - if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) { - /* - * Ignore whether this WCxx call succeeds or not since - * the previously executed WQxx method call might have - * succeeded, and returning the failing status code - * of this call would throw away the result of the WQxx - * call, potentially leaking memory. - */ - acpi_execute_simple_method(handle, wc_method, 0); - } - - return status; + return acpi_evaluate_object(handle, method, &input, out); } /** @@ -421,9 +417,15 @@ acpi_status wmi_query_block(const char *guid_string, u8 instance, if (IS_ERR(wdev)) return AE_ERROR; + if (wmi_device_enable(wdev, true) < 0) + dev_warn(&wdev->dev, "Failed to enable device\n"); + wblock = container_of(wdev, struct wmi_block, dev); status = __query_block(wblock, instance, out); + if (wmi_device_enable(wdev, false) < 0) + dev_warn(&wdev->dev, "Failed to disable device\n"); + wmi_device_put(wdev); return status; @@ -470,7 +472,14 @@ acpi_status wmi_set_block(const char *guid_string, u8 instance, const struct acp if (IS_ERR(wdev)) return AE_ERROR; + if (wmi_device_enable(wdev, true) < 0) + dev_warn(&wdev->dev, "Failed to enable device\n"); + status = wmidev_block_set(wdev, instance, in); + + if (wmi_device_enable(wdev, false) < 0) + dev_warn(&wdev->dev, "Failed to disable device\n"); + wmi_device_put(wdev); return status; @@ -551,7 +560,7 @@ acpi_status wmi_install_notify_handler(const char *guid, wblock->handler = handler; wblock->handler_data = data; - if (ACPI_FAILURE(wmi_method_enable(wblock, true))) + if (wmi_device_enable(wdev, true) < 0) dev_warn(&wblock->dev.dev, "Failed to enable device\n"); status = AE_OK; @@ -588,7 +597,7 @@ acpi_status wmi_remove_notify_handler(const char *guid) if (!wblock->handler) { status = AE_NULL_ENTRY; } else { - if (ACPI_FAILURE(wmi_method_enable(wblock, false))) + if (wmi_device_enable(wdev, false) < 0) dev_warn(&wblock->dev.dev, "Failed to disable device\n"); wblock->handler = NULL; @@ -821,11 +830,19 @@ static int wmi_dev_match(struct device *dev, const struct device_driver *driver) return 0; } +static void wmi_dev_disable(void *data) +{ + struct device *dev = data; + + if (wmi_device_enable(to_wmi_device(dev), false) < 0) + dev_warn(dev, "Failed to disable device\n"); +} + static int wmi_dev_probe(struct device *dev) { struct wmi_block *wblock = dev_to_wblock(dev); struct wmi_driver *wdriver = to_wmi_driver(dev->driver); - int ret = 0; + int ret; /* Some older WMI drivers will break if instantiated multiple times, * so they are blocked from probing WMI devices with a duplicated GUID. @@ -844,18 +861,22 @@ static int wmi_dev_probe(struct device *dev) return -ENODEV; } - if (ACPI_FAILURE(wmi_method_enable(wblock, true))) + if (wmi_device_enable(to_wmi_device(dev), true) < 0) dev_warn(dev, "failed to enable device -- probing anyway\n"); + /* + * We have to make sure that all devres-managed resources are released first because + * some might still want to access the underlying WMI device. + */ + ret = devm_add_action_or_reset(dev, wmi_dev_disable, dev); + if (ret < 0) + return ret; + if (wdriver->probe) { ret = wdriver->probe(to_wmi_device(dev), find_guid_context(wblock, wdriver)); - if (ret) { - if (ACPI_FAILURE(wmi_method_enable(wblock, false))) - dev_warn(dev, "Failed to disable device\n"); - + if (ret) return ret; - } } down_write(&wblock->notify_lock); @@ -876,9 +897,6 @@ static void wmi_dev_remove(struct device *dev) if (wdriver->remove) wdriver->remove(to_wmi_device(dev)); - - if (ACPI_FAILURE(wmi_method_enable(wblock, false))) - dev_warn(dev, "failed to disable device\n"); } static void wmi_dev_shutdown(struct device *dev) @@ -902,7 +920,11 @@ static void wmi_dev_shutdown(struct device *dev) if (wdriver->shutdown) wdriver->shutdown(to_wmi_device(dev)); - if (ACPI_FAILURE(wmi_method_enable(wblock, false))) + /* + * We still need to disable the WMI device here since devres-managed resources + * like wmi_dev_disable() will not be release during shutdown. + */ + if (wmi_device_enable(to_wmi_device(dev), false) < 0) dev_warn(dev, "Failed to disable device\n"); } } @@ -965,6 +987,19 @@ static int guid_count(const guid_t *guid) return context.count; } +static int wmi_dev_set_name(struct wmi_block *wblock, int count) +{ + if (IS_ENABLED(CONFIG_ACPI_WMI_LEGACY_DEVICE_NAMES)) { + if (count) + return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, + count); + else + return dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid); + } + + return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, wblock->dev.dev.id); +} + static int wmi_create_device(struct device *wmi_bus_dev, struct wmi_block *wblock, struct acpi_device *device) @@ -973,7 +1008,7 @@ static int wmi_create_device(struct device *wmi_bus_dev, struct acpi_device_info *info; acpi_handle method_handle; acpi_status status; - int count; + int count, ret; if (wblock->gblock.flags & ACPI_WMI_EVENT) { wblock->dev.dev.type = &wmi_type_event; @@ -1044,11 +1079,18 @@ static int wmi_create_device(struct device *wmi_bus_dev, if (count < 0) return count; - if (count) { - dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, count); + if (count) set_bit(WMI_GUID_DUPLICATED, &wblock->flags); - } else { - dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid); + + ret = ida_alloc(&wmi_ida, GFP_KERNEL); + if (ret < 0) + return ret; + + wblock->dev.dev.id = ret; + ret = wmi_dev_set_name(wblock, count); + if (ret < 0) { + ida_free(&wmi_ida, wblock->dev.dev.id); + return ret; } device_initialize(&wblock->dev.dev); @@ -1134,6 +1176,7 @@ static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev) dev_err(wmi_bus_dev, "failed to register %pUL\n", &wblock->gblock.guid); + ida_free(&wmi_ida, wblock->dev.dev.id); put_device(&wblock->dev.dev); } } @@ -1233,7 +1276,10 @@ static void acpi_wmi_notify_handler(acpi_handle handle, u32 event, void *context static int wmi_remove_device(struct device *dev, void *data) { + int id = dev->id; + device_unregister(dev); + ida_free(&wmi_ida, id); return 0; } |