Input: wacom - don't use on-stack memory for report buffers

Tested-by: Martin Capitanio <martin@capitanio.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c
index a9d5031b855e5b3c529cbd5e8b8589cf46fcebab..ea30c983a33efdbd6469cbd2fbc07fe308ade8fe 100644 (file)
--- a/drivers/input/tablet/wacom_sys.c
+++ b/drivers/input/tablet/wacom_sys.c
@@ -388,6 +388,32 @@ static int wacom_parse_hid(struct usb_interface *intf, struct hid_descriptor *hi
        return result;
 }
 
+static int wacom_query_tablet_data(struct usb_interface *intf)
+{
+       unsigned char *rep_data;
+       int limit = 0;
+       int error;
+
+       rep_data = kmalloc(2, GFP_KERNEL);
+       if (!rep_data)
+               return -ENOMEM;
+
+       do {
+               rep_data[0] = 2;
+               rep_data[1] = 2;
+               error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
+                                       2, rep_data, 2);
+               if (error >= 0)
+                       error = usb_get_report(intf,
+                                               WAC_HID_FEATURE_REPORT, 2,
+                                               rep_data, 2);
+       } while ((error < 0 || rep_data[1] != 2) && limit++ < 5);
+
+       kfree(rep_data);
+
+       return error < 0 ? error : 0;
+}
+
 static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
        struct usb_device *dev = interface_to_usbdev(intf);
@@ -398,7 +424,6 @@ static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *i
        struct wacom_features *features;
        struct input_dev *input_dev;
        int error = -ENOMEM;
-       char rep_data[2], limit = 0;
        struct hid_descriptor *hid_desc;
 
        wacom = kzalloc(sizeof(struct wacom), GFP_KERNEL);
@@ -489,20 +514,10 @@ static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *i
 
        /*
         * Ask the tablet to report tablet data if it is not a Tablet PC.
-        * Repeat until it succeeds
+        * Note that if query fails it is not a hard failure.
         */
-       if (wacom_wac->features->type != TABLETPC) {
-               do {
-                       rep_data[0] = 2;
-                       rep_data[1] = 2;
-                       error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
-                                               2, rep_data, 2);
-                       if (error >= 0)
-                               error = usb_get_report(intf,
-                                               WAC_HID_FEATURE_REPORT, 2,
-                                               rep_data, 2);
-               } while ((error < 0 || rep_data[1] != 2) && limit++ < 5);
-       }
+       if (wacom_wac->features->type != TABLETPC)
+               wacom_query_tablet_data(intf);
 
        usb_set_intfdata(intf, wacom);
        return 0;