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authorMichał Kępień <kernel@kempniu.pl>2016-03-04 16:09:08 +0300
committerDarren Hart <dvhart@linux.intel.com>2016-03-23 20:05:50 +0300
commite09c4d5b15438bd86ff8bfb05d70f17915bb5979 (patch)
tree5a42f7273b2cffc7bdd87142075fb41f36b887f4 /drivers/platform/x86/dell-wmi.c
parent0db2180fce6ada548f03c4f456ba2113753cdba9 (diff)
downloadlinux-e09c4d5b15438bd86ff8bfb05d70f17915bb5979.tar.xz
dell-wmi: enable receiving WMI events on Dell Vostro V131
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@kempniu.pl> Reviewed-by: Pali Rohár <pali.rohar@gmail.com> Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Diffstat (limited to 'drivers/platform/x86/dell-wmi.c')
-rw-r--r--drivers/platform/x86/dell-wmi.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c
index e38258a82be5..65edd93df7de 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@redhat.com>");
MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
@@ -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();
}