1 files changed, 95 insertions, 123 deletions

diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
index 0fbfbaa8d8e3..cd199fbe4dc9 100644
--- a/drivers/acpi/device_sysfs.c
+++ b/drivers/acpi/device_sysfs.c
@@ -158,8 +158,8 @@ static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalia
 		return 0;
 
 	len = snprintf(modalias, size, "acpi:");
-	if (len <= 0)
-		return len;
+	if (len >= size)
+		return -ENOMEM;
 
 	size -= len;
 
@@ -168,8 +168,6 @@ static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalia
 			continue;
 
 		count = snprintf(&modalias[len], size, "%s:", id->id);
-		if (count < 0)
-			return -EINVAL;
 
 		if (count >= size)
 			return -ENOMEM;
@@ -177,7 +175,7 @@ static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalia
 		len += count;
 		size -= count;
 	}
-	modalias[len] = '\0';
+
 	return len;
 }
 
@@ -212,8 +210,10 @@ static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias
 	len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer);
 	ACPI_FREE(buf.pointer);
 
-	if (len <= 0)
-		return len;
+	if (len >= size)
+		return -ENOMEM;
+
+	size -= len;
 
 	of_compatible = acpi_dev->data.of_compatible;
 	if (of_compatible->type == ACPI_TYPE_PACKAGE) {
@@ -226,8 +226,6 @@ static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias
 	for (i = 0; i < nval; i++, obj++) {
 		count = snprintf(&modalias[len], size, "C%s",
 				 obj->string.pointer);
-		if (count < 0)
-			return -EINVAL;
 
 		if (count >= size)
 			return -ENOMEM;
@@ -235,7 +233,7 @@ static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias
 		len += count;
 		size -= count;
 	}
-	modalias[len] = '\0';
+
 	return len;
 }
 
@@ -283,7 +281,7 @@ int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env
 }
 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
 
-static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size)
+static int __acpi_device_modalias(const struct acpi_device *adev, char *buf, int size)
 {
 	int len, count;
 
@@ -410,7 +408,7 @@ static ssize_t uid_show(struct device *dev,
 {
 	struct acpi_device *acpi_dev = to_acpi_device(dev);
 
-	return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
+	return sprintf(buf, "%s\n", acpi_device_uid(acpi_dev));
 }
 static DEVICE_ATTR_RO(uid);
 
@@ -441,23 +439,33 @@ static ssize_t description_show(struct device *dev,
 				char *buf)
 {
 	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	union acpi_object *str_obj;
+	acpi_status status;
 	int result;
 
-	if (acpi_dev->pnp.str_obj == NULL)
-		return 0;
+	status = acpi_evaluate_object_typed(acpi_dev->handle, "_STR",
+					    NULL, &buffer,
+					    ACPI_TYPE_BUFFER);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	str_obj = buffer.pointer;
 
 	/*
 	 * The _STR object contains a Unicode identifier for a device.
 	 * We need to convert to utf-8 so it can be displayed.
 	 */
 	result = utf16s_to_utf8s(
-		(wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
-		acpi_dev->pnp.str_obj->buffer.length,
+		(wchar_t *)str_obj->buffer.pointer,
+		str_obj->buffer.length,
 		UTF16_LITTLE_ENDIAN, buf,
 		PAGE_SIZE - 1);
 
 	buf[result++] = '\n';
 
+	ACPI_FREE(str_obj);
+
 	return result;
 }
 static DEVICE_ATTR_RO(description);
@@ -509,96 +517,97 @@ static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(status);
 
-/**
- * acpi_device_setup_files - Create sysfs attributes of an ACPI device.
- * @dev: ACPI device object.
- */
-int acpi_device_setup_files(struct acpi_device *dev)
-{
-	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
-	acpi_status status;
-	int result = 0;
+static struct attribute *acpi_attrs[] = {
+	&dev_attr_path.attr,
+	&dev_attr_hid.attr,
+	&dev_attr_modalias.attr,
+	&dev_attr_description.attr,
+	&dev_attr_adr.attr,
+	&dev_attr_uid.attr,
+	&dev_attr_sun.attr,
+	&dev_attr_hrv.attr,
+	&dev_attr_status.attr,
+	&dev_attr_eject.attr,
+	&dev_attr_power_state.attr,
+	&dev_attr_real_power_state.attr,
+	NULL
+};
 
+static bool acpi_show_attr(struct acpi_device *dev, const struct device_attribute *attr)
+{
 	/*
 	 * Devices gotten from FADT don't have a "path" attribute
 	 */
-	if (dev->handle) {
-		result = device_create_file(&dev->dev, &dev_attr_path);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_path)
+		return dev->handle;
 
-	if (!list_empty(&dev->pnp.ids)) {
-		result = device_create_file(&dev->dev, &dev_attr_hid);
-		if (result)
-			goto end;
+	if (attr == &dev_attr_hid || attr == &dev_attr_modalias)
+		return !list_empty(&dev->pnp.ids);
 
-		result = device_create_file(&dev->dev, &dev_attr_modalias);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_description)
+		return acpi_has_method(dev->handle, "_STR");
 
-	/*
-	 * If device has _STR, 'description' file is created
-	 */
-	if (acpi_has_method(dev->handle, "_STR")) {
-		status = acpi_evaluate_object(dev->handle, "_STR",
-					NULL, &buffer);
-		if (ACPI_FAILURE(status))
-			buffer.pointer = NULL;
-		dev->pnp.str_obj = buffer.pointer;
-		result = device_create_file(&dev->dev, &dev_attr_description);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_adr)
+		return dev->pnp.type.bus_address;
 
-	if (dev->pnp.type.bus_address)
-		result = device_create_file(&dev->dev, &dev_attr_adr);
-	if (dev->pnp.unique_id)
-		result = device_create_file(&dev->dev, &dev_attr_uid);
+	if (attr == &dev_attr_uid)
+		return acpi_device_uid(dev);
 
-	if (acpi_has_method(dev->handle, "_SUN")) {
-		result = device_create_file(&dev->dev, &dev_attr_sun);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_sun)
+		return acpi_has_method(dev->handle, "_SUN");
 
-	if (acpi_has_method(dev->handle, "_HRV")) {
-		result = device_create_file(&dev->dev, &dev_attr_hrv);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_hrv)
+		return acpi_has_method(dev->handle, "_HRV");
 
-	if (acpi_has_method(dev->handle, "_STA")) {
-		result = device_create_file(&dev->dev, &dev_attr_status);
-		if (result)
-			goto end;
-	}
+	if (attr == &dev_attr_status)
+		return acpi_has_method(dev->handle, "_STA");
 
 	/*
 	 * If device has _EJ0, 'eject' file is created that is used to trigger
 	 * hot-removal function from userland.
 	 */
-	if (acpi_has_method(dev->handle, "_EJ0")) {
-		result = device_create_file(&dev->dev, &dev_attr_eject);
-		if (result)
-			return result;
-	}
+	if (attr == &dev_attr_eject)
+		return acpi_has_method(dev->handle, "_EJ0");
 
-	if (dev->flags.power_manageable) {
-		result = device_create_file(&dev->dev, &dev_attr_power_state);
-		if (result)
-			return result;
+	if (attr == &dev_attr_power_state)
+		return dev->flags.power_manageable;
 
-		if (dev->power.flags.power_resources)
-			result = device_create_file(&dev->dev,
-						    &dev_attr_real_power_state);
-	}
+	if (attr == &dev_attr_real_power_state)
+		return dev->flags.power_manageable && dev->power.flags.power_resources;
 
-	acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
+	dev_warn_once(&dev->dev, "Unexpected attribute: %s\n", attr->attr.name);
+	return false;
+}
 
-end:
-	return result;
+static umode_t acpi_attr_is_visible(struct kobject *kobj,
+				    struct attribute *attr,
+				    int attrno)
+{
+	struct acpi_device *dev = to_acpi_device(kobj_to_dev(kobj));
+
+	if (acpi_show_attr(dev, container_of(attr, struct device_attribute, attr)))
+		return attr->mode;
+	else
+		return 0;
+}
+
+static const struct attribute_group acpi_group = {
+	.attrs = acpi_attrs,
+	.is_visible = acpi_attr_is_visible,
+};
+
+const struct attribute_group *acpi_groups[] = {
+	&acpi_group,
+	NULL
+};
+
+/**
+ * acpi_device_setup_files - Create sysfs attributes of an ACPI device.
+ * @dev: ACPI device object.
+ */
+void acpi_device_setup_files(struct acpi_device *dev)
+{
+	acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data);
 }
 
 /**
@@ -608,41 +617,4 @@ end:
 void acpi_device_remove_files(struct acpi_device *dev)
 {
 	acpi_hide_nondev_subnodes(&dev->data);
-
-	if (dev->flags.power_manageable) {
-		device_remove_file(&dev->dev, &dev_attr_power_state);
-		if (dev->power.flags.power_resources)
-			device_remove_file(&dev->dev,
-					   &dev_attr_real_power_state);
-	}
-
-	/*
-	 * If device has _STR, remove 'description' file
-	 */
-	if (acpi_has_method(dev->handle, "_STR")) {
-		kfree(dev->pnp.str_obj);
-		device_remove_file(&dev->dev, &dev_attr_description);
-	}
-	/*
-	 * If device has _EJ0, remove 'eject' file.
-	 */
-	if (acpi_has_method(dev->handle, "_EJ0"))
-		device_remove_file(&dev->dev, &dev_attr_eject);
-
-	if (acpi_has_method(dev->handle, "_SUN"))
-		device_remove_file(&dev->dev, &dev_attr_sun);
-
-	if (acpi_has_method(dev->handle, "_HRV"))
-		device_remove_file(&dev->dev, &dev_attr_hrv);
-
-	if (dev->pnp.unique_id)
-		device_remove_file(&dev->dev, &dev_attr_uid);
-	if (dev->pnp.type.bus_address)
-		device_remove_file(&dev->dev, &dev_attr_adr);
-	device_remove_file(&dev->dev, &dev_attr_modalias);
-	device_remove_file(&dev->dev, &dev_attr_hid);
-	if (acpi_has_method(dev->handle, "_STA"))
-		device_remove_file(&dev->dev, &dev_attr_status);
-	if (dev->handle)
-		device_remove_file(&dev->dev, &dev_attr_path);
 }