From e0668f28888184f6c633110a37386f2d4a6fa00e Mon Sep 17 00:00:00 2001 From: Yurii Pavlovskyi Date: Tue, 14 May 2019 21:00:31 +0200 Subject: platform/x86: asus-wmi: Improve DSTS WMI method ID detection The DSTS method detection mistakenly selects DCTS instead of DSTS if nothing is returned when the method ID is not defined in WMNB. As a result, the control of keyboard backlight is not functional for TUF Gaming series laptops. Implement detection based on _UID of the WMI device instead. There is evidence that DCTS is handled by ACPI WMI devices that have _UID ASUSWMI, whereas none of the devices without ASUSWMI respond to DCTS and DSTS is used instead [1]. DSDT examples: FX505GM (_UID ATK): Method (WMNB, 3, Serialized) { ... If ((Local0 == 0x53545344)) { ... Return (Zero) } ... // No return } K54C (_UID ATK): Method (WMNB, 3, Serialized) { ... If ((Local0 == 0x53545344)) { ... Return (0x02) } ... Return (0xFFFFFFFE) } [1] Link: https://lkml.org/lkml/2019/4/11/322 Signed-off-by: Yurii Pavlovskyi Suggested-by: Daniel Drake Signed-off-by: Andy Shevchenko --- drivers/platform/x86/asus-wmi.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) (limited to 'drivers/platform') diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c index c67f11e0d6e7..ef526dcfeac5 100644 --- a/drivers/platform/x86/asus-wmi.c +++ b/drivers/platform/x86/asus-wmi.c @@ -83,6 +83,8 @@ MODULE_LICENSE("GPL"); #define USB_INTEL_XUSB2PR 0xD0 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI 0x9c31 +#define ASUS_ACPI_UID_ASUSWMI "ASUSWMI" + static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL }; static bool ashs_present(void) @@ -1874,6 +1876,8 @@ static int asus_wmi_sysfs_init(struct platform_device *device) */ static int asus_wmi_platform_init(struct asus_wmi *asus) { + struct device *dev = &asus->platform_device->dev; + char *wmi_uid; int rv; /* INIT enable hotkeys on some models */ @@ -1903,11 +1907,24 @@ static int asus_wmi_platform_init(struct asus_wmi *asus) * Note, on most Eeepc, there is no way to check if a method exist * or note, while on notebooks, they returns 0xFFFFFFFE on failure, * but once again, SPEC may probably be used for that kind of things. + * + * Additionally at least TUF Gaming series laptops return nothing for + * unknown methods, so the detection in this way is not possible. + * + * There is strong indication that only ACPI WMI devices that have _UID + * equal to "ASUSWMI" use DCTS whereas those with "ATK" use DSTS. */ - if (!asus_wmi_evaluate_method(ASUS_WMI_METHODID_DSTS, 0, 0, NULL)) + wmi_uid = wmi_get_acpi_device_uid(ASUS_WMI_MGMT_GUID); + if (!wmi_uid) + return -ENODEV; + + if (!strcmp(wmi_uid, ASUS_ACPI_UID_ASUSWMI)) { + dev_info(dev, "Detected ASUSWMI, use DCTS\n"); + asus->dsts_id = ASUS_WMI_METHODID_DCTS; + } else { + dev_info(dev, "Detected %s, not ASUSWMI, use DSTS\n", wmi_uid); asus->dsts_id = ASUS_WMI_METHODID_DSTS; - else - asus->dsts_id = ASUS_WMI_METHODID_DSTS2; + } /* CWAP allow to define the behavior of the Fn+F2 key, * this method doesn't seems to be present on Eee PCs */ -- cgit v1.2.3-55-g7522