From 1caab3c1a90be3aa4ec3599409d8fe044b077478 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Wed, 4 Nov 2009 14:17:53 -0500 Subject: wmi: Add support for module autoloading WMI provides interface-specific GUIDs that are exported from modules as modalises, but the core currently generates no events to trigger module loading. This patch adds support for registering devices for each WMI GUID and generating the appropriate uevent. Based heavily on a patch by Carlos Corbacho (). Signed-off-by: Matthew Garrett Tested-by: Carlos Corbacho Acked-by: Carlos Corbacho Signed-off-by: Len Brown --- drivers/platform/x86/wmi.c | 175 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 173 insertions(+), 2 deletions(-) (limited to 'drivers/platform/x86/wmi.c') diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 177f8d767df..e425a868cd3 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -65,6 +66,7 @@ struct wmi_block { acpi_handle handle; wmi_notify_handler handler; void *handler_data; + struct device *dev; }; static struct wmi_block wmi_blocks; @@ -195,6 +197,34 @@ static bool wmi_parse_guid(const u8 *src, u8 *dest) return true; } +/* + * Convert a raw GUID to the ACII string representation + */ +static int wmi_gtoa(const char *in, char *out) +{ + int i; + + for (i = 3; i >= 0; i--) + out += sprintf(out, "%02X", in[i] & 0xFF); + + out += sprintf(out, "-"); + out += sprintf(out, "%02X", in[5] & 0xFF); + out += sprintf(out, "%02X", in[4] & 0xFF); + out += sprintf(out, "-"); + out += sprintf(out, "%02X", in[7] & 0xFF); + out += sprintf(out, "%02X", in[6] & 0xFF); + out += sprintf(out, "-"); + out += sprintf(out, "%02X", in[8] & 0xFF); + out += sprintf(out, "%02X", in[9] & 0xFF); + out += sprintf(out, "-"); + + for (i = 10; i <= 15; i++) + out += sprintf(out, "%02X", in[i] & 0xFF); + + out = '\0'; + return 0; +} + static bool find_guid(const char *guid_string, struct wmi_block **out) { char tmp[16], guid_input[16]; @@ -554,6 +584,138 @@ bool wmi_has_guid(const char *guid_string) } EXPORT_SYMBOL_GPL(wmi_has_guid); +/* + * sysfs interface + */ +static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, + char *buf) +{ + char guid_string[37]; + struct wmi_block *wblock; + + wblock = dev_get_drvdata(dev); + if (!wblock) + return -ENOMEM; + + wmi_gtoa(wblock->gblock.guid, guid_string); + + return sprintf(buf, "wmi:%s\n", guid_string); +} +static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); + +static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + char guid_string[37]; + + struct wmi_block *wblock; + + if (add_uevent_var(env, "MODALIAS=")) + return -ENOMEM; + + wblock = dev_get_drvdata(dev); + if (!wblock) + return -ENOMEM; + + wmi_gtoa(wblock->gblock.guid, guid_string); + + strcpy(&env->buf[env->buflen - 1], "wmi:"); + memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36); + env->buflen += 40; + + return 0; +} + +static void wmi_dev_free(struct device *dev) +{ + kfree(dev); +} + +static struct class wmi_class = { + .name = "wmi", + .dev_release = wmi_dev_free, + .dev_uevent = wmi_dev_uevent, +}; + +static int wmi_create_devs(void) +{ + int result; + char guid_string[37]; + struct guid_block *gblock; + struct wmi_block *wblock; + struct list_head *p; + struct device *guid_dev; + + /* Create devices for all the GUIDs */ + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + + guid_dev = kzalloc(sizeof(struct device), GFP_KERNEL); + if (!guid_dev) + return -ENOMEM; + + wblock->dev = guid_dev; + + guid_dev->class = &wmi_class; + dev_set_drvdata(guid_dev, wblock); + + gblock = &wblock->gblock; + + wmi_gtoa(gblock->guid, guid_string); + dev_set_name(guid_dev, guid_string); + + result = device_register(guid_dev); + if (result) + return result; + + result = device_create_file(guid_dev, &dev_attr_modalias); + if (result) + return result; + } + + return 0; +} + +static void wmi_remove_devs(void) +{ + struct guid_block *gblock; + struct wmi_block *wblock; + struct list_head *p; + struct device *guid_dev; + + /* Delete devices for all the GUIDs */ + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + + guid_dev = wblock->dev; + gblock = &wblock->gblock; + + device_remove_file(guid_dev, &dev_attr_modalias); + + device_unregister(guid_dev); + } +} + +static void wmi_class_exit(void) +{ + wmi_remove_devs(); + class_unregister(&wmi_class); +} + +static int wmi_class_init(void) +{ + int ret; + + ret = class_register(&wmi_class); + if (ret) + return ret; + + ret = wmi_create_devs(); + if (ret) + wmi_class_exit(); + + return ret; +} + /* * Parse the _WDG method for the GUID data blocks */ @@ -709,10 +871,17 @@ static int __init acpi_wmi_init(void) if (result < 0) { printk(KERN_INFO PREFIX "Error loading mapper\n"); - } else { - printk(KERN_INFO PREFIX "Mapper loaded\n"); + return -ENODEV; + } + + result = wmi_class_init(); + if (result) { + acpi_bus_unregister_driver(&acpi_wmi_driver); + return result; } + printk(KERN_INFO PREFIX "Mapper loaded\n"); + return result; } @@ -721,6 +890,8 @@ static void __exit acpi_wmi_exit(void) struct list_head *p, *tmp; struct wmi_block *wblock; + wmi_class_exit(); + acpi_bus_unregister_driver(&acpi_wmi_driver); list_for_each_safe(p, tmp, &wmi_blocks.list) { -- cgit v1.2.3-70-g09d2 From 3e9b988e4edf065d39c1343937f717319b1c1065 Mon Sep 17 00:00:00 2001 From: Anisse Astier Date: Fri, 4 Dec 2009 10:10:09 +0100 Subject: wmi: Free the allocated acpi objects through wmi_get_event_data These function allocate an acpi object by calling wmi_get_event_data, which then calls acpi_evaluate_object, and it is not freed afterwards. And kernel doc is fixed for parameters of wmi_get_event_data. Signed-off-by: Anisse Astier Acked-by: Randy Dunlap Acked-by: Carlos Corbacho Signed-off-by: Len Brown --- drivers/platform/x86/dell-wmi.c | 1 + drivers/platform/x86/hp-wmi.c | 2 ++ drivers/platform/x86/wmi.c | 4 ++-- 3 files changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/platform/x86/wmi.c') diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c index 67f3fe71c50..6561dfc028e 100644 --- a/drivers/platform/x86/dell-wmi.c +++ b/drivers/platform/x86/dell-wmi.c @@ -238,6 +238,7 @@ static void dell_wmi_notify(u32 value, void *context) input_sync(dell_wmi_input_dev); } } + kfree(obj); } diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c index 63c3e658a88..db10c5d007e 100644 --- a/drivers/platform/x86/hp-wmi.c +++ b/drivers/platform/x86/hp-wmi.c @@ -381,6 +381,8 @@ static void hp_wmi_notify(u32 value, void *context) } else printk(KERN_INFO "HP WMI: Unknown key pressed - %x\n", eventcode); + + kfree(obj); } static int __init hp_wmi_input_setup(void) diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index e425a868cd3..9f93d6c0f51 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -540,8 +540,8 @@ EXPORT_SYMBOL_GPL(wmi_remove_notify_handler); /** * wmi_get_event_data - Get WMI data associated with an event * - * @event - Event to find - * &out - Buffer to hold event data + * @event: Event to find + * @out: Buffer to hold event data. out->pointer should be freed with kfree() * * Returns extra data associated with an event in WMI. */ -- cgit v1.2.3-70-g09d2 From c03b26a5a5597a59b2e247d005d5901430109a8a Mon Sep 17 00:00:00 2001 From: Paul Rolland Date: Wed, 30 Dec 2009 01:07:40 -0500 Subject: wmi: check find_guid() return value to prevent oops Signed-off-by: Paul Rolland Signed-off-by: Len Brown --- drivers/platform/x86/wmi.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'drivers/platform/x86/wmi.c') diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 9f93d6c0f51..cc9ad740bda 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -492,8 +492,7 @@ wmi_notify_handler handler, void *data) if (!guid || !handler) return AE_BAD_PARAMETER; - find_guid(guid, &block); - if (!block) + if (!find_guid(guid, &block)) return AE_NOT_EXIST; if (block->handler) @@ -521,8 +520,7 @@ acpi_status wmi_remove_notify_handler(const char *guid) if (!guid) return AE_BAD_PARAMETER; - find_guid(guid, &block); - if (!block) + if (!find_guid(guid, &block)) return AE_NOT_EXIST; if (!block->handler) -- cgit v1.2.3-70-g09d2 From d1f9e4970742bb1e22d07b01bd44f9c357d25c42 Mon Sep 17 00:00:00 2001 From: Carlos Corbacho Date: Sat, 26 Dec 2009 19:14:59 +0000 Subject: ACPI: WMI: Survive BIOS with duplicate GUIDs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It would appear that in BIOS's with nVidia hooks, the GUID 05901221-D566-11D1-B2F0-00A0C9062910 is duplicated. For now, the simplest solution is to just ignore any duplicate GUIDs. These particular hooks are not currently supported/ used in the kernel, so whoever does that can figure out what the 'right' solution should be (if there's a better one). http://bugzilla.kernel.org/show_bug.cgi?id=14846 Signed-off-by: Carlos Corbacho Reported-by: Larry Finger Reported-by: Oldřich Jedlička Signed-off-by: Len Brown --- drivers/platform/x86/wmi.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'drivers/platform/x86/wmi.c') diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index cc9ad740bda..b104302fea0 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -714,6 +714,22 @@ static int wmi_class_init(void) return ret; } +static bool guid_already_parsed(const char *guid_string) +{ + struct guid_block *gblock; + struct wmi_block *wblock; + struct list_head *p; + + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + gblock = &wblock->gblock; + + if (strncmp(gblock->guid, guid_string, 16) == 0) + return true; + } + return false; +} + /* * Parse the _WDG method for the GUID data blocks */ @@ -723,6 +739,7 @@ static __init acpi_status parse_wdg(acpi_handle handle) union acpi_object *obj; struct guid_block *gblock; struct wmi_block *wblock; + char guid_string[37]; acpi_status status; u32 i, total; @@ -745,6 +762,19 @@ static __init acpi_status parse_wdg(acpi_handle handle) memcpy(gblock, obj->buffer.pointer, obj->buffer.length); for (i = 0; i < total; i++) { + /* + Some WMI devices, like those for nVidia hooks, have a + duplicate GUID. It's not clear what we should do in this + case yet, so for now, we'll just ignore the duplicate. + Anyone who wants to add support for that device can come + up with a better workaround for the mess then. + */ + if (guid_already_parsed(gblock[i].guid) == true) { + wmi_gtoa(gblock[i].guid, guid_string); + printk(KERN_INFO PREFIX "Skipping duplicate GUID %s\n", + guid_string); + continue; + } wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL); if (!wblock) return AE_NO_MEMORY; -- cgit v1.2.3-70-g09d2