| /* |
| * WMI embedded Binary MOF driver |
| * |
| * Copyright (c) 2015 Andrew Lutomirski |
| * Copyright (C) 2017 VMware, Inc. All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published |
| * by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/acpi.h> |
| #include <linux/device.h> |
| #include <linux/fs.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/string.h> |
| #include <linux/sysfs.h> |
| #include <linux/types.h> |
| #include <linux/wmi.h> |
| |
| #define WMI_BMOF_GUID "05901221-D566-11D1-B2F0-00A0C9062910" |
| |
| struct bmof_priv { |
| union acpi_object *bmofdata; |
| struct bin_attribute bmof_bin_attr; |
| }; |
| |
| static ssize_t |
| read_bmof(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *attr, |
| char *buf, loff_t off, size_t count) |
| { |
| struct bmof_priv *priv = |
| container_of(attr, struct bmof_priv, bmof_bin_attr); |
| |
| if (off < 0) |
| return -EINVAL; |
| |
| if (off >= priv->bmofdata->buffer.length) |
| return 0; |
| |
| if (count > priv->bmofdata->buffer.length - off) |
| count = priv->bmofdata->buffer.length - off; |
| |
| memcpy(buf, priv->bmofdata->buffer.pointer + off, count); |
| return count; |
| } |
| |
| static int wmi_bmof_probe(struct wmi_device *wdev) |
| { |
| struct bmof_priv *priv; |
| int ret; |
| |
| priv = devm_kzalloc(&wdev->dev, sizeof(struct bmof_priv), GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| dev_set_drvdata(&wdev->dev, priv); |
| |
| priv->bmofdata = wmidev_block_query(wdev, 0); |
| if (!priv->bmofdata) { |
| dev_err(&wdev->dev, "failed to read Binary MOF\n"); |
| return -EIO; |
| } |
| |
| if (priv->bmofdata->type != ACPI_TYPE_BUFFER) { |
| dev_err(&wdev->dev, "Binary MOF is not a buffer\n"); |
| ret = -EIO; |
| goto err_free; |
| } |
| |
| sysfs_bin_attr_init(&priv->bmof_bin_attr); |
| priv->bmof_bin_attr.attr.name = "bmof"; |
| priv->bmof_bin_attr.attr.mode = 0400; |
| priv->bmof_bin_attr.read = read_bmof; |
| priv->bmof_bin_attr.size = priv->bmofdata->buffer.length; |
| |
| ret = sysfs_create_bin_file(&wdev->dev.kobj, &priv->bmof_bin_attr); |
| if (ret) |
| goto err_free; |
| |
| return 0; |
| |
| err_free: |
| kfree(priv->bmofdata); |
| return ret; |
| } |
| |
| static int wmi_bmof_remove(struct wmi_device *wdev) |
| { |
| struct bmof_priv *priv = dev_get_drvdata(&wdev->dev); |
| |
| sysfs_remove_bin_file(&wdev->dev.kobj, &priv->bmof_bin_attr); |
| kfree(priv->bmofdata); |
| return 0; |
| } |
| |
| static const struct wmi_device_id wmi_bmof_id_table[] = { |
| { .guid_string = WMI_BMOF_GUID }, |
| { }, |
| }; |
| |
| static struct wmi_driver wmi_bmof_driver = { |
| .driver = { |
| .name = "wmi-bmof", |
| }, |
| .probe = wmi_bmof_probe, |
| .remove = wmi_bmof_remove, |
| .id_table = wmi_bmof_id_table, |
| }; |
| |
| module_wmi_driver(wmi_bmof_driver); |
| |
| MODULE_DEVICE_TABLE(wmi, wmi_bmof_id_table); |
| MODULE_AUTHOR("Andrew Lutomirski <luto@kernel.org>"); |
| MODULE_DESCRIPTION("WMI embedded Binary MOF driver"); |
| MODULE_LICENSE("GPL"); |