ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/platform/x86/dell-wmi-descriptor.c b/marvell/linux/drivers/platform/x86/dell-wmi-descriptor.c
new file mode 100644
index 0000000..a068900
--- /dev/null
+++ b/marvell/linux/drivers/platform/x86/dell-wmi-descriptor.c
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Dell WMI descriptor driver
+ *
+ * Copyright (C) 2017 Dell Inc. All Rights Reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/wmi.h>
+#include "dell-wmi-descriptor.h"
+
+#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492"
+
+struct descriptor_priv {
+ struct list_head list;
+ u32 interface_version;
+ u32 size;
+ u32 hotfix;
+};
+static int descriptor_valid = -EPROBE_DEFER;
+static LIST_HEAD(wmi_list);
+static DEFINE_MUTEX(list_mutex);
+
+int dell_wmi_get_descriptor_valid(void)
+{
+ if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID))
+ return -ENODEV;
+
+ return descriptor_valid;
+}
+EXPORT_SYMBOL_GPL(dell_wmi_get_descriptor_valid);
+
+bool dell_wmi_get_interface_version(u32 *version)
+{
+ struct descriptor_priv *priv;
+ bool ret = false;
+
+ mutex_lock(&list_mutex);
+ priv = list_first_entry_or_null(&wmi_list,
+ struct descriptor_priv,
+ list);
+ if (priv) {
+ *version = priv->interface_version;
+ ret = true;
+ }
+ mutex_unlock(&list_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dell_wmi_get_interface_version);
+
+bool dell_wmi_get_size(u32 *size)
+{
+ struct descriptor_priv *priv;
+ bool ret = false;
+
+ mutex_lock(&list_mutex);
+ priv = list_first_entry_or_null(&wmi_list,
+ struct descriptor_priv,
+ list);
+ if (priv) {
+ *size = priv->size;
+ ret = true;
+ }
+ mutex_unlock(&list_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dell_wmi_get_size);
+
+bool dell_wmi_get_hotfix(u32 *hotfix)
+{
+ struct descriptor_priv *priv;
+ bool ret = false;
+
+ mutex_lock(&list_mutex);
+ priv = list_first_entry_or_null(&wmi_list,
+ struct descriptor_priv,
+ list);
+ if (priv) {
+ *hotfix = priv->hotfix;
+ ret = true;
+ }
+ mutex_unlock(&list_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dell_wmi_get_hotfix);
+
+/*
+ * Descriptor buffer is 128 byte long and contains:
+ *
+ * Name Offset Length Value
+ * Vendor Signature 0 4 "DELL"
+ * Object Signature 4 4 " WMI"
+ * WMI Interface Version 8 4 <version>
+ * WMI buffer length 12 4 <length>
+ * WMI hotfix number 16 4 <hotfix>
+ */
+static int dell_wmi_descriptor_probe(struct wmi_device *wdev,
+ const void *context)
+{
+ union acpi_object *obj = NULL;
+ struct descriptor_priv *priv;
+ u32 *buffer;
+ int ret;
+
+ obj = wmidev_block_query(wdev, 0);
+ if (!obj) {
+ dev_err(&wdev->dev, "failed to read Dell WMI descriptor\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ if (obj->type != ACPI_TYPE_BUFFER) {
+ dev_err(&wdev->dev, "Dell descriptor has wrong type\n");
+ ret = -EINVAL;
+ descriptor_valid = ret;
+ goto out;
+ }
+
+ /* Although it's not technically a failure, this would lead to
+ * unexpected behavior
+ */
+ if (obj->buffer.length != 128) {
+ dev_err(&wdev->dev,
+ "Dell descriptor buffer has unexpected length (%d)\n",
+ obj->buffer.length);
+ ret = -EINVAL;
+ descriptor_valid = ret;
+ goto out;
+ }
+
+ buffer = (u32 *)obj->buffer.pointer;
+
+ if (strncmp(obj->string.pointer, "DELL WMI", 8) != 0) {
+ dev_err(&wdev->dev, "Dell descriptor buffer has invalid signature (%8ph)\n",
+ buffer);
+ ret = -EINVAL;
+ descriptor_valid = ret;
+ goto out;
+ }
+ descriptor_valid = 0;
+
+ if (buffer[2] != 0 && buffer[2] != 1)
+ dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%lu)\n",
+ (unsigned long) buffer[2]);
+
+ priv = devm_kzalloc(&wdev->dev, sizeof(struct descriptor_priv),
+ GFP_KERNEL);
+
+ if (!priv) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ priv->interface_version = buffer[2];
+ priv->size = buffer[3];
+ priv->hotfix = buffer[4];
+ ret = 0;
+ dev_set_drvdata(&wdev->dev, priv);
+ mutex_lock(&list_mutex);
+ list_add_tail(&priv->list, &wmi_list);
+ mutex_unlock(&list_mutex);
+
+ dev_dbg(&wdev->dev, "Detected Dell WMI interface version %lu, buffer size %lu, hotfix %lu\n",
+ (unsigned long) priv->interface_version,
+ (unsigned long) priv->size,
+ (unsigned long) priv->hotfix);
+
+out:
+ kfree(obj);
+ return ret;
+}
+
+static int dell_wmi_descriptor_remove(struct wmi_device *wdev)
+{
+ struct descriptor_priv *priv = dev_get_drvdata(&wdev->dev);
+
+ mutex_lock(&list_mutex);
+ list_del(&priv->list);
+ mutex_unlock(&list_mutex);
+ return 0;
+}
+
+static const struct wmi_device_id dell_wmi_descriptor_id_table[] = {
+ { .guid_string = DELL_WMI_DESCRIPTOR_GUID },
+ { },
+};
+
+static struct wmi_driver dell_wmi_descriptor_driver = {
+ .driver = {
+ .name = "dell-wmi-descriptor",
+ },
+ .probe = dell_wmi_descriptor_probe,
+ .remove = dell_wmi_descriptor_remove,
+ .id_table = dell_wmi_descriptor_id_table,
+};
+
+module_wmi_driver(dell_wmi_descriptor_driver);
+
+MODULE_DEVICE_TABLE(wmi, dell_wmi_descriptor_id_table);
+MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
+MODULE_DESCRIPTION("Dell WMI descriptor driver");
+MODULE_LICENSE("GPL");