staging: quickstart: fix up sysfs file permissions

Use the default DEVICE_ATTR_RO/RW macros to specify the file permissions
better, and make them easier to audit.

And did we really want any user to be able to write to this file, I kind
of doubt it...

Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/quickstart/quickstart.c

@@ -71,9 +71,8 @@ static struct quickstart_button *pressed;
 static struct input_dev *quickstart_input;
 
 /* Platform driver functions */
-static ssize_t quickstart_buttons_show(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
+static ssize_t buttons_show(struct device *dev, struct device_attribute *attr,
+			    char *buf)
 {
 	int count = 0;
 	struct quickstart_button *b;
@@ -94,18 +93,17 @@ static ssize_t quickstart_buttons_show(struct device *dev,
 	return count;
 }
 
-static ssize_t quickstart_pressed_button_show(struct device *dev,
-						struct device_attribute *attr,
-						char *buf)
+static ssize_t pressed_button_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
 {
 	return scnprintf(buf, PAGE_SIZE, "%s\n",
 					(pressed ? pressed->name : "none"));
 }
 
 
-static ssize_t quickstart_pressed_button_store(struct device *dev,
-						struct device_attribute *attr,
-						const char *buf, size_t count)
+static ssize_t pressed_button_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
 {
 	if (count < 2)
 		return -EINVAL;
@@ -319,9 +317,8 @@ static int quickstart_acpi_remove(struct acpi_device *device)
 }
 
 /* Platform driver structs */
-static DEVICE_ATTR(pressed_button, 0666, quickstart_pressed_button_show,
-					 quickstart_pressed_button_store);
-static DEVICE_ATTR(buttons, 0444, quickstart_buttons_show, NULL);
+static DEVICE_ATTR_RW(pressed_button);
+static DEVICE_ATTR_RO(buttons);
 static struct platform_device *pf_device;
 static struct platform_driver pf_driver = {
 	.driver = {