1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/thermal/int340x_thermal/acpi_thermal_rel.c b/drivers/thermal/int340x_thermal/acpi_thermal_rel.c
new file mode 100644
index 000000000000..0d8db808f0ae
--- /dev/null
+++ b/drivers/thermal/int340x_thermal/acpi_thermal_rel.c
@@ -0,0 +1,400 @@
+/* acpi_thermal_rel.c driver for exporting ACPI thermal relationship
+ *
+ * Copyright (c) 2014 Intel Corp
+ *
+ * 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.
+ *
+ */
+
+/*
+ * Two functionalities included:
+ * 1. Export _TRT, _ART, via misc device interface to the userspace.
+ * 2. Provide parsing result to kernel drivers
+ *
+ */
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/acpi.h>
+#include <linux/uaccess.h>
+#include <linux/miscdevice.h>
+#include "acpi_thermal_rel.h"
+
+static acpi_handle acpi_thermal_rel_handle;
+static DEFINE_SPINLOCK(acpi_thermal_rel_chrdev_lock);
+static int acpi_thermal_rel_chrdev_count;	/* #times opened */
+static int acpi_thermal_rel_chrdev_exclu;	/* already open exclusive? */
+
+static int acpi_thermal_rel_open(struct inode *inode, struct file *file)
+{
+	spin_lock(&acpi_thermal_rel_chrdev_lock);
+	if (acpi_thermal_rel_chrdev_exclu ||
+	    (acpi_thermal_rel_chrdev_count && (file->f_flags & O_EXCL))) {
+		spin_unlock(&acpi_thermal_rel_chrdev_lock);
+		return -EBUSY;
+	}
+
+	if (file->f_flags & O_EXCL)
+		acpi_thermal_rel_chrdev_exclu = 1;
+	acpi_thermal_rel_chrdev_count++;
+
+	spin_unlock(&acpi_thermal_rel_chrdev_lock);
+
+	return nonseekable_open(inode, file);
+}
+
+static int acpi_thermal_rel_release(struct inode *inode, struct file *file)
+{
+	spin_lock(&acpi_thermal_rel_chrdev_lock);
+	acpi_thermal_rel_chrdev_count--;
+	acpi_thermal_rel_chrdev_exclu = 0;
+	spin_unlock(&acpi_thermal_rel_chrdev_lock);
+
+	return 0;
+}
+
+/**
+ * acpi_parse_trt - Thermal Relationship Table _TRT for passive cooling
+ *
+ * @handle: ACPI handle of the device contains _TRT
+ * @art_count: the number of valid entries resulted from parsing _TRT
+ * @artp: pointer to pointer of array of art entries in parsing result
+ * @create_dev: whether to create platform devices for target and source
+ *
+ */
+int acpi_parse_trt(acpi_handle handle, int *trt_count, struct trt **trtp,
+		bool create_dev)
+{
+	acpi_status status;
+	int result = 0;
+	int i;
+	int nr_bad_entries = 0;
+	struct trt *trts;
+	struct acpi_device *adev;
+	union acpi_object *p;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct acpi_buffer element = { 0, NULL };
+	struct acpi_buffer trt_format = { sizeof("RRNNNNNN"), "RRNNNNNN" };
+
+	if (!acpi_has_method(handle, "_TRT"))
+		return 0;
+
+	status = acpi_evaluate_object(handle, "_TRT", NULL, &buffer);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	p = buffer.pointer;
+	if (!p || (p->type != ACPI_TYPE_PACKAGE)) {
+		pr_err("Invalid _TRT data\n");
+		result = -EFAULT;
+		goto end;
+	}
+
+	*trt_count = p->package.count;
+	trts = kzalloc(*trt_count * sizeof(struct trt), GFP_KERNEL);
+	if (!trts) {
+		result = -ENOMEM;
+		goto end;
+	}
+
+	for (i = 0; i < *trt_count; i++) {
+		struct trt *trt = &trts[i - nr_bad_entries];
+
+		element.length = sizeof(struct trt);
+		element.pointer = trt;
+
+		status = acpi_extract_package(&(p->package.elements[i]),
+					      &trt_format, &element);
+		if (ACPI_FAILURE(status)) {
+			nr_bad_entries++;
+			pr_warn("_TRT package %d is invalid, ignored\n", i);
+			continue;
+		}
+		if (!create_dev)
+			continue;
+
+		result = acpi_bus_get_device(trt->source, &adev);
+		if (!result)
+			acpi_create_platform_device(adev);
+		else
+			pr_warn("Failed to get source ACPI device\n");
+
+		result = acpi_bus_get_device(trt->target, &adev);
+		if (!result)
+			acpi_create_platform_device(adev);
+		else
+			pr_warn("Failed to get target ACPI device\n");
+	}
+
+	*trtp = trts;
+	/* don't count bad entries */
+	*trt_count -= nr_bad_entries;
+end:
+	kfree(buffer.pointer);
+	return result;
+}
+EXPORT_SYMBOL(acpi_parse_trt);
+
+/**
+ * acpi_parse_art - Parse Active Relationship Table _ART
+ *
+ * @handle: ACPI handle of the device contains _ART
+ * @art_count: the number of valid entries resulted from parsing _ART
+ * @artp: pointer to pointer of array of art entries in parsing result
+ * @create_dev: whether to create platform devices for target and source
+ *
+ */
+int acpi_parse_art(acpi_handle handle, int *art_count, struct art **artp,
+		bool create_dev)
+{
+	acpi_status status;
+	int result = 0;
+	int i;
+	int nr_bad_entries = 0;
+	struct art *arts;
+	struct acpi_device *adev;
+	union acpi_object *p;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct acpi_buffer element = { 0, NULL };
+	struct acpi_buffer art_format =	{
+		sizeof("RRNNNNNNNNNNN"), "RRNNNNNNNNNNN" };
+
+	if (!acpi_has_method(handle, "_ART"))
+		return 0;
+
+	status = acpi_evaluate_object(handle, "_ART", NULL, &buffer);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	p = buffer.pointer;
+	if (!p || (p->type != ACPI_TYPE_PACKAGE)) {
+		pr_err("Invalid _ART data\n");
+		result = -EFAULT;
+		goto end;
+	}
+
+	/* ignore p->package.elements[0], as this is _ART Revision field */
+	*art_count = p->package.count - 1;
+	arts = kzalloc(*art_count * sizeof(struct art), GFP_KERNEL);
+	if (!arts) {
+		result = -ENOMEM;
+		goto end;
+	}
+
+	for (i = 0; i < *art_count; i++) {
+		struct art *art = &arts[i - nr_bad_entries];
+
+		element.length = sizeof(struct art);
+		element.pointer = art;
+
+		status = acpi_extract_package(&(p->package.elements[i + 1]),
+					      &art_format, &element);
+		if (ACPI_FAILURE(status)) {
+			pr_warn("_ART package %d is invalid, ignored", i);
+			nr_bad_entries++;
+			continue;
+		}
+		if (!create_dev)
+			continue;
+
+		if (art->source) {
+			result = acpi_bus_get_device(art->source, &adev);
+			if (!result)
+				acpi_create_platform_device(adev);
+			else
+				pr_warn("Failed to get source ACPI device\n");
+		}
+		if (art->target) {
+			result = acpi_bus_get_device(art->target, &adev);
+			if (!result)
+				acpi_create_platform_device(adev);
+			else
+				pr_warn("Failed to get source ACPI device\n");
+		}
+	}
+
+	*artp = arts;
+	/* don't count bad entries */
+	*art_count -= nr_bad_entries;
+end:
+	kfree(buffer.pointer);
+	return result;
+}
+EXPORT_SYMBOL(acpi_parse_art);
+
+
+/* get device name from acpi handle */
+static void get_single_name(acpi_handle handle, char *name)
+{
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
+
+	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer)))
+		pr_warn("Failed get name from handle\n");
+	else {
+		memcpy(name, buffer.pointer, ACPI_NAME_SIZE);
+		kfree(buffer.pointer);
+	}
+}
+
+static int fill_art(char __user *ubuf)
+{
+	int i;
+	int ret;
+	int count;
+	int art_len;
+	struct art *arts = NULL;
+	union art_object *art_user;
+
+	ret = acpi_parse_art(acpi_thermal_rel_handle, &count, &arts, false);
+	if (ret)
+		goto free_art;
+	art_len = count * sizeof(union art_object);
+	art_user = kzalloc(art_len, GFP_KERNEL);
+	if (!art_user) {
+		ret = -ENOMEM;
+		goto free_art;
+	}
+	/* now fill in user art data */
+	for (i = 0; i < count; i++) {
+		/* userspace art needs device name instead of acpi reference */
+		get_single_name(arts[i].source, art_user[i].source_device);
+		get_single_name(arts[i].target, art_user[i].target_device);
+		/* copy the rest int data in addition to source and target */
+		memcpy(&art_user[i].weight, &arts[i].weight,
+			sizeof(u64) * (ACPI_NR_ART_ELEMENTS - 2));
+	}
+
+	if (copy_to_user(ubuf, art_user, art_len))
+		ret = -EFAULT;
+	kfree(art_user);
+free_art:
+	kfree(arts);
+	return ret;
+}
+
+static int fill_trt(char __user *ubuf)
+{
+	int i;
+	int ret;
+	int count;
+	int trt_len;
+	struct trt *trts = NULL;
+	union trt_object *trt_user;
+
+	ret = acpi_parse_trt(acpi_thermal_rel_handle, &count, &trts, false);
+	if (ret)
+		goto free_trt;
+	trt_len = count * sizeof(union trt_object);
+	trt_user = kzalloc(trt_len, GFP_KERNEL);
+	if (!trt_user) {
+		ret = -ENOMEM;
+		goto free_trt;
+	}
+	/* now fill in user trt data */
+	for (i = 0; i < count; i++) {
+		/* userspace trt needs device name instead of acpi reference */
+		get_single_name(trts[i].source, trt_user[i].source_device);
+		get_single_name(trts[i].target, trt_user[i].target_device);
+		trt_user[i].sample_period = trts[i].sample_period;
+		trt_user[i].influence = trts[i].influence;
+	}
+
+	if (copy_to_user(ubuf, trt_user, trt_len))
+		ret = -EFAULT;
+	kfree(trt_user);
+free_trt:
+	kfree(trts);
+	return ret;
+}
+
+static long acpi_thermal_rel_ioctl(struct file *f, unsigned int cmd,
+				   unsigned long __arg)
+{
+	int ret = 0;
+	unsigned long length = 0;
+	unsigned long count = 0;
+	char __user *arg = (void __user *)__arg;
+	struct trt *trts;
+	struct art *arts;
+
+	switch (cmd) {
+	case ACPI_THERMAL_GET_TRT_COUNT:
+		ret = acpi_parse_trt(acpi_thermal_rel_handle, (int *)&count,
+				&trts, false);
+		kfree(trts);
+		if (!ret)
+			return put_user(count, (unsigned long __user *)__arg);
+		return ret;
+	case ACPI_THERMAL_GET_TRT_LEN:
+		ret = acpi_parse_trt(acpi_thermal_rel_handle, (int *)&count,
+				&trts, false);
+		kfree(trts);
+		length = count * sizeof(union trt_object);
+		if (!ret)
+			return put_user(length, (unsigned long __user *)__arg);
+		return ret;
+	case ACPI_THERMAL_GET_TRT:
+		return fill_trt(arg);
+	case ACPI_THERMAL_GET_ART_COUNT:
+		ret = acpi_parse_art(acpi_thermal_rel_handle, (int *)&count,
+				&arts, false);
+		kfree(arts);
+		if (!ret)
+			return put_user(count, (unsigned long __user *)__arg);
+		return ret;
+	case ACPI_THERMAL_GET_ART_LEN:
+		ret = acpi_parse_art(acpi_thermal_rel_handle, (int *)&count,
+				&arts, false);
+		kfree(arts);
+		length = count * sizeof(union art_object);
+		if (!ret)
+			return put_user(length, (unsigned long __user *)__arg);
+		return ret;
+
+	case ACPI_THERMAL_GET_ART:
+		return fill_art(arg);
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+static const struct file_operations acpi_thermal_rel_fops = {
+	.owner		= THIS_MODULE,
+	.open		= acpi_thermal_rel_open,
+	.release	= acpi_thermal_rel_release,
+	.unlocked_ioctl	= acpi_thermal_rel_ioctl,
+	.llseek		= no_llseek,
+};
+
+static struct miscdevice acpi_thermal_rel_misc_device = {
+	.minor	= MISC_DYNAMIC_MINOR,
+	"acpi_thermal_rel",
+	&acpi_thermal_rel_fops
+};
+
+int acpi_thermal_rel_misc_device_add(acpi_handle handle)
+{
+	acpi_thermal_rel_handle = handle;
+
+	return misc_register(&acpi_thermal_rel_misc_device);
+}
+EXPORT_SYMBOL(acpi_thermal_rel_misc_device_add);
+
+int acpi_thermal_rel_misc_device_remove(acpi_handle handle)
+{
+	misc_deregister(&acpi_thermal_rel_misc_device);
+
+	return 0;
+}
+EXPORT_SYMBOL(acpi_thermal_rel_misc_device_remove);
+
+MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
+MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com");
+MODULE_DESCRIPTION("Intel acpi thermal rel misc dev driver");
+MODULE_LICENSE("GPL v2");