Input: implement new force feedback interface

Implement a new force feedback interface, in which all non-driver-specific
operations are separated to a common module. This includes handling effect
type validations, locking, etc.

The effects are now file descriptor specific instead of the previous strange
half-process half-fd specific behaviour. The effect memory of devices is not
emptied if the root user opens and closes the device while another user is
using effects. This is a minor change and most likely no force feedback
aware programs are affected by this negatively.

Otherwise the userspace interface is left unaltered.

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 9cb4b9a54f01..1fc0517e9428 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -176,6 +176,10 @@ void input_event(struct input_dev *dev, unsigned int type, unsigned int code, in
                         break;
 
                 case EV_FF:
+
+                        if (value < 0)
+                                return;
+
                         if (dev->event)
                                 dev->event(dev, type, code, value);
                         break;
@@ -762,7 +766,9 @@ static void input_dev_release(struct class_device *class_dev)
 {
         struct input_dev *dev = to_input_dev(class_dev);
 
+        input_ff_destroy(dev);
         kfree(dev);
+
         module_put(THIS_MODULE);
 }