On some laptop models (e.g. Dell Vostro V131), WMI events are not generated until a specific SMBIOS request is issued to register an event listener [1]. As there seems to be no ACPI method or SMBIOS request to determine without possible side effects whether a given machine needs to issue this SMBIOS request in order to receive WMI events, DMI matching is used to whitelist the models which need it. [1] https://lists.us.dell.com/pipermail/libsmbios-devel/2015-July/000612.html Signed-off-by: Michał Kępień <kernel@xxxxxxxxxx> Reviewed-by: Pali Rohár <pali.rohar@xxxxxxxxx> --- drivers/platform/x86/Kconfig | 1 + drivers/platform/x86/dell-wmi.c | 66 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 67 insertions(+) diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index a65d974..ed2004b 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -124,6 +124,7 @@ config DELL_WMI depends on DMI depends on INPUT depends on ACPI_VIDEO || ACPI_VIDEO = n + depends on DELL_SMBIOS select INPUT_SPARSEKMAP ---help--- Say Y here if you want to support WMI-based hotkeys on Dell laptops. diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c index e38258a..65edd93 100644 --- a/drivers/platform/x86/dell-wmi.c +++ b/drivers/platform/x86/dell-wmi.c @@ -37,6 +37,7 @@ #include <linux/string.h> #include <linux/dmi.h> #include <acpi/video.h> +#include "dell-smbios.h" MODULE_AUTHOR("Matthew Garrett <mjg@xxxxxxxxxx>"); MODULE_AUTHOR("Pali Rohár <pali.rohar@xxxxxxxxx>"); @@ -47,10 +48,29 @@ MODULE_LICENSE("GPL"); #define DELL_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" static u32 dell_wmi_interface_version; +static bool wmi_requires_smbios_request; MODULE_ALIAS("wmi:"DELL_EVENT_GUID); MODULE_ALIAS("wmi:"DELL_DESCRIPTOR_GUID); +static int __init dmi_matched(const struct dmi_system_id *dmi) +{ + wmi_requires_smbios_request = 1; + return 1; +} + +static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = { + { + .callback = dmi_matched, + .ident = "Dell Vostro V131", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"), + }, + }, + { } +}; + /* * Certain keys are flagged as KE_IGNORE. All of these are either * notifications (rather than requests for change) or are also sent @@ -597,6 +617,38 @@ static int __init dell_wmi_check_descriptor_buffer(void) return 0; } +/* + * According to Dell SMBIOS documentation: + * + * 17 3 Application Program Registration + * + * cbArg1 Application ID 1 = 0x00010000 + * cbArg2 Application ID 2 + * QUICKSET/DCP = 0x51534554 "QSET" + * ALS Driver = 0x416c7353 "AlsS" + * Latitude ON = 0x4c6f6e52 "LonR" + * cbArg3 Application version or revision number + * cbArg4 0 = Unregister application + * 1 = Register application + * cbRes1 Standard return codes (0, -1, -2) + */ + +static int dell_wmi_events_set_enabled(bool enable) +{ + struct calling_interface_buffer *buffer; + int ret; + + buffer = dell_smbios_get_buffer(); + buffer->input[0] = 0x10000; + buffer->input[1] = 0x51534554; + buffer->input[3] = enable; + dell_smbios_send_request(17, 3); + ret = buffer->output[0]; + dell_smbios_release_buffer(); + + return dell_smbios_error(ret); +} + static int __init dell_wmi_init(void) { int err; @@ -624,12 +676,26 @@ static int __init dell_wmi_init(void) return -ENODEV; } + dmi_check_system(dell_wmi_smbios_list); + + if (wmi_requires_smbios_request) { + err = dell_wmi_events_set_enabled(true); + if (err) { + pr_err("Failed to enable WMI events\n"); + wmi_remove_notify_handler(DELL_EVENT_GUID); + dell_wmi_input_destroy(); + return err; + } + } + return 0; } module_init(dell_wmi_init); static void __exit dell_wmi_exit(void) { + if (wmi_requires_smbios_request) + dell_wmi_events_set_enabled(false); wmi_remove_notify_handler(DELL_EVENT_GUID); dell_wmi_input_destroy(); } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
