From 3dda3b3798f96d2974b5f60811142d3e25547807 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Fri, 25 Nov 2016 17:11:41 +0100 Subject: [PATCH] platform/x86: Add custom surface3 platform device for controlling LID The LID state provided by ACPI on the Surface 3 is not accurate. The ACPI node doesn't get notified on LID open, which means the LID input switch stays close most of the time. Fortunatelly, there is a WMI method which directly queries the GPIO underneath the LID state, so it's far more reliable than ACPI. To get the notifications that the LID was opened/closed, we can rely on the ACPI notification of the touchscreen: the DSDT shows that the touchscreen will get notified on close/open as it also controls its _STA method. Note that we need to set the tag "power-switch" to the LID input node through a udev rule for logind to accept it: SUBSYSTEM=="input", KERNEL=="event*", KERNELS=="surface3-wmi", \ TAG+="power-switch" Signed-off-by: Benjamin Tissoires Signed-off-by: Andy Shevchenko --- drivers/platform/x86/Kconfig | 12 ++ drivers/platform/x86/Makefile | 1 + drivers/platform/x86/surface3-wmi.c | 296 ++++++++++++++++++++++++++++ 3 files changed, 309 insertions(+) create mode 100644 drivers/platform/x86/surface3-wmi.c diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index 4639d970f8cb..0414d76dc15c 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -363,6 +363,18 @@ config IDEAPAD_LAPTOP This is a driver for Lenovo IdeaPad netbooks contains drivers for rfkill switch, hotkey, fan control and backlight control. +config SURFACE3_WMI + tristate "Surface 3 WMI Driver" + depends on ACPI_WMI + depends on DMI + depends on INPUT + depends on SPI + ---help--- + Say Y here if you have a Surface 3. + + To compile this driver as a module, choose M here: the module will + be called surface3-wmi. + config THINKPAD_ACPI tristate "ThinkPad ACPI Laptop Extras" depends on ACPI diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile index 2d6a587bded5..6cd3d909b759 100644 --- a/drivers/platform/x86/Makefile +++ b/drivers/platform/x86/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_PANASONIC_LAPTOP) += panasonic-laptop.o obj-$(CONFIG_INTEL_MENLOW) += intel_menlow.o obj-$(CONFIG_ACPI_WMI) += wmi.o obj-$(CONFIG_MSI_WMI) += msi-wmi.o +obj-$(CONFIG_SURFACE3_WMI) += surface3-wmi.o obj-$(CONFIG_TOPSTAR_LAPTOP) += topstar-laptop.o # toshiba_acpi must link after wmi to ensure that wmi devices are found diff --git a/drivers/platform/x86/surface3-wmi.c b/drivers/platform/x86/surface3-wmi.c new file mode 100644 index 000000000000..5553b2b85e0a --- /dev/null +++ b/drivers/platform/x86/surface3-wmi.c @@ -0,0 +1,296 @@ +/* + * Driver for the LID cover switch of the Surface 3 + * + * Copyright (c) 2016 Red Hat Inc. + */ + +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; version 2 of the License. + */ + +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Benjamin Tissoires "); +MODULE_DESCRIPTION("Surface 3 platform driver"); +MODULE_LICENSE("GPL"); + +#define ACPI_BUTTON_HID_LID "PNP0C0D" +#define SPI_CTL_OBJ_NAME "SPI" +#define SPI_TS_OBJ_NAME "NTRG" + +#define SURFACE3_LID_GUID "F7CC25EC-D20B-404C-8903-0ED4359C18AE" + +MODULE_ALIAS("wmi:" SURFACE3_LID_GUID); + +static const struct dmi_system_id surface3_dmi_table[] = { +#if defined(CONFIG_X86) + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"), + DMI_MATCH(DMI_PRODUCT_NAME, "Surface 3"), + }, + }, +#endif + { } +}; + +struct surface3_wmi { + struct acpi_device *touchscreen_adev; + struct acpi_device *pnp0c0d_adev; + struct acpi_hotplug_context hp; + struct input_dev *input; +}; + +static struct platform_device *s3_wmi_pdev; + +static struct surface3_wmi s3_wmi; + +static DEFINE_MUTEX(s3_wmi_lock); + +static int s3_wmi_query_block(const char *guid, int instance, int *ret) +{ + acpi_status status; + union acpi_object *obj; + + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + + mutex_lock(&s3_wmi_lock); + status = wmi_query_block(guid, instance, &output); + + obj = output.pointer; + + if (!obj || obj->type != ACPI_TYPE_INTEGER) { + if (obj) { + pr_err("query block returned object type: %d - buffer length:%d\n", + obj->type, + obj->type == ACPI_TYPE_BUFFER ? + obj->buffer.length : 0); + } + kfree(obj); + return -EINVAL; + } + *ret = obj->integer.value; + kfree(obj); + mutex_unlock(&s3_wmi_lock); + return 0; +} + +static inline int s3_wmi_query_lid(int *ret) +{ + return s3_wmi_query_block(SURFACE3_LID_GUID, 0, ret); +} + +static int s3_wmi_send_lid_state(void) +{ + int ret, lid_sw; + + ret = s3_wmi_query_lid(&lid_sw); + if (ret) + return ret; + + input_report_switch(s3_wmi.input, SW_LID, lid_sw); + input_sync(s3_wmi.input); + + return 0; +} + +static int s3_wmi_hp_notify(struct acpi_device *adev, u32 value) +{ + return s3_wmi_send_lid_state(); +} + +static acpi_status s3_wmi_attach_spi_device(acpi_handle handle, + u32 level, + void *data, + void **return_value) +{ + struct acpi_device *adev, **ts_adev; + + if (acpi_bus_get_device(handle, &adev)) + return AE_OK; + + ts_adev = data; + + if (strncmp(acpi_device_bid(adev), SPI_TS_OBJ_NAME, + strlen(SPI_TS_OBJ_NAME))) + return AE_OK; + + if (*ts_adev) { + pr_err("duplicate entry %s\n", SPI_TS_OBJ_NAME); + return AE_OK; + } + + *ts_adev = adev; + + return AE_OK; +} + +static int s3_wmi_check_platform_device(struct device *dev, void *data) +{ + struct acpi_device *adev, *ts_adev; + acpi_handle handle; + acpi_status status; + + /* ignore non ACPI devices */ + handle = ACPI_HANDLE(dev); + if (!handle || acpi_bus_get_device(handle, &adev)) + return 0; + + /* check for LID ACPI switch */ + if (!strcmp(ACPI_BUTTON_HID_LID, acpi_device_hid(adev))) { + s3_wmi.pnp0c0d_adev = adev; + return 0; + } + + /* ignore non SPI controllers */ + if (strncmp(acpi_device_bid(adev), SPI_CTL_OBJ_NAME, + strlen(SPI_CTL_OBJ_NAME))) + return 0; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + s3_wmi_attach_spi_device, NULL, + &ts_adev, NULL); + if (ACPI_FAILURE(status)) + dev_warn(dev, "failed to enumerate SPI slaves\n"); + + if (!ts_adev) + return 0; + + s3_wmi.touchscreen_adev = ts_adev; + + return 0; +} + +static int s3_wmi_create_and_register_input(struct platform_device *pdev) +{ + struct input_dev *input; + int error; + + input = devm_input_allocate_device(&pdev->dev); + if (!input) + return -ENOMEM; + + input->name = "Lid Switch"; + input->phys = "button/input0"; + input->id.bustype = BUS_HOST; + input->id.product = 0x0005; + + input_set_capability(input, EV_SW, SW_LID); + + error = input_register_device(input); + if (error) + goto out_err; + + s3_wmi.input = input; + + return 0; + out_err: + input_free_device(s3_wmi.input); + return error; +} + +static int __init s3_wmi_probe(struct platform_device *pdev) +{ + int error; + + if (!dmi_check_system(surface3_dmi_table)) + return -ENODEV; + + memset(&s3_wmi, 0, sizeof(s3_wmi)); + + bus_for_each_dev(&platform_bus_type, NULL, NULL, + s3_wmi_check_platform_device); + + if (!s3_wmi.touchscreen_adev) + return -ENODEV; + + acpi_bus_trim(s3_wmi.pnp0c0d_adev); + + error = s3_wmi_create_and_register_input(pdev); + if (error) + goto restore_acpi_lid; + + acpi_initialize_hp_context(s3_wmi.touchscreen_adev, &s3_wmi.hp, + s3_wmi_hp_notify, NULL); + + s3_wmi_send_lid_state(); + + return 0; + + restore_acpi_lid: + acpi_bus_scan(s3_wmi.pnp0c0d_adev->handle); + return error; +} + +static int s3_wmi_remove(struct platform_device *device) +{ + /* remove the hotplug context from the acpi device */ + s3_wmi.touchscreen_adev->hp = NULL; + + /* reinstall the actual PNPC0C0D LID default handle */ + acpi_bus_scan(s3_wmi.pnp0c0d_adev->handle); + return 0; +} + +#ifdef CONFIG_PM +static int s3_wmi_resume(struct device *dev) +{ + s3_wmi_send_lid_state(); + return 0; +} +#endif +static SIMPLE_DEV_PM_OPS(s3_wmi_pm, NULL, s3_wmi_resume); + +static struct platform_driver s3_wmi_driver = { + .driver = { + .name = "surface3-wmi", + .pm = &s3_wmi_pm, + }, + .remove = s3_wmi_remove, +}; + +static int __init s3_wmi_init(void) +{ + int error; + + s3_wmi_pdev = platform_device_alloc("surface3-wmi", -1); + if (!s3_wmi_pdev) + return -ENOMEM; + + error = platform_device_add(s3_wmi_pdev); + if (error) + goto err_device_put; + + error = platform_driver_probe(&s3_wmi_driver, s3_wmi_probe); + if (error) + goto err_device_del; + + pr_info("Surface 3 WMI Extras loaded\n"); + return 0; + + err_device_del: + platform_device_del(s3_wmi_pdev); + err_device_put: + platform_device_put(s3_wmi_pdev); + return error; +} + +static void __exit s3_wmi_exit(void) +{ + platform_device_unregister(s3_wmi_pdev); + platform_driver_unregister(&s3_wmi_driver); +} + +module_init(s3_wmi_init); +module_exit(s3_wmi_exit); -- 2.20.1