// SPDX-License-Identifier: GPL-2.0-only/* *  Driver for the LID cover switch of the Surface 3 * *  Copyright (c) 2016 Red Hat Inc. */  #include <linux/kernel.h>#include <linux/module.h>#include <linux/slab.h> #include <linux/acpi.h>#include <linux/dmi.h>#include <linux/input.h>#include <linux/mutex.h>#include <linux/platform_device.h>#include <linux/spi/spi.h> MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@redhat.com>");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){	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };	union acpi_object *obj = NULL;	acpi_status status;	int error = 0; 	mutex_lock(&s3_wmi_lock);	status = wmi_query_block(guid, instance, &output);	if (ACPI_FAILURE(status)) {		error = -EIO;		goto out_free_unlock;	} 	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);		}		error = -EINVAL;		goto out_free_unlock;	}	*ret = obj->integer.value; out_free_unlock:	kfree(obj);	mutex_unlock(&s3_wmi_lock);	return error;} 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 = acpi_fetch_acpi_dev(handle);	struct acpi_device **ts_adev = data; 	if (!adev || 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 = ACPI_COMPANION(dev);	struct acpi_device *ts_adev = NULL;	acpi_status status; 	/* ignore non ACPI devices */	if (!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, adev->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)		return error; 	s3_wmi.input = input; 	return 0;} 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 void 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);} static int __maybe_unused s3_wmi_resume(struct device *dev){	s3_wmi_send_lid_state();	return 0;}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);