1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * WMI embedded Binary MOF driver 4 * 5 * Copyright (c) 2015 Andrew Lutomirski 6 * Copyright (C) 2017 VMware, Inc. All Rights Reserved. 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #include <linux/device.h> 12 #include <linux/fs.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/string.h> 16 #include <linux/sysfs.h> 17 #include <linux/types.h> 18 #include <linux/wmi.h> 19 20 #define WMI_BMOF_GUID "05901221-D566-11D1-B2F0-00A0C9062910" 21 22 static ssize_t bmof_read(struct file *filp, struct kobject *kobj, const struct bin_attribute *attr, 23 char *buf, loff_t off, size_t count) 24 { 25 struct device *dev = kobj_to_dev(kobj); 26 struct wmi_buffer *buffer = dev_get_drvdata(dev); 27 28 return memory_read_from_buffer(buf, count, &off, buffer->data, buffer->length); 29 } 30 31 static const BIN_ATTR_ADMIN_RO(bmof, 0); 32 33 static const struct bin_attribute * const bmof_attrs[] = { 34 &bin_attr_bmof, 35 NULL 36 }; 37 38 static size_t bmof_bin_size(struct kobject *kobj, const struct bin_attribute *attr, int n) 39 { 40 struct device *dev = kobj_to_dev(kobj); 41 struct wmi_buffer *buffer = dev_get_drvdata(dev); 42 43 return buffer->length; 44 } 45 46 static const struct attribute_group bmof_group = { 47 .bin_size = bmof_bin_size, 48 .bin_attrs = bmof_attrs, 49 }; 50 51 static const struct attribute_group *bmof_groups[] = { 52 &bmof_group, 53 NULL 54 }; 55 56 static int wmi_bmof_probe(struct wmi_device *wdev, const void *context) 57 { 58 struct wmi_buffer *buffer; 59 int ret; 60 61 buffer = devm_kzalloc(&wdev->dev, sizeof(*buffer), GFP_KERNEL); 62 if (!buffer) 63 return -ENOMEM; 64 65 ret = wmidev_query_block(wdev, 0, buffer); 66 if (ret < 0) 67 return ret; 68 69 dev_set_drvdata(&wdev->dev, buffer); 70 71 return 0; 72 } 73 74 static void wmi_bmof_remove(struct wmi_device *wdev) 75 { 76 struct wmi_buffer *buffer = dev_get_drvdata(&wdev->dev); 77 78 kfree(buffer->data); 79 } 80 81 static const struct wmi_device_id wmi_bmof_id_table[] = { 82 { .guid_string = WMI_BMOF_GUID }, 83 { }, 84 }; 85 86 static struct wmi_driver wmi_bmof_driver = { 87 .driver = { 88 .name = "wmi-bmof", 89 .dev_groups = bmof_groups, 90 }, 91 .probe = wmi_bmof_probe, 92 .remove = wmi_bmof_remove, 93 .id_table = wmi_bmof_id_table, 94 .no_singleton = true, 95 }; 96 97 module_wmi_driver(wmi_bmof_driver); 98 99 MODULE_DEVICE_TABLE(wmi, wmi_bmof_id_table); 100 MODULE_AUTHOR("Andrew Lutomirski <luto@kernel.org>"); 101 MODULE_DESCRIPTION("WMI embedded Binary MOF driver"); 102 MODULE_LICENSE("GPL"); 103