1 files changed, 37 insertions, 36 deletions

diff --git a/drivers/input/ff-memless.c b/drivers/input/ff-memless.c
index 74c0d8c6002a..e0c1c61aae71 100644
--- a/drivers/input/ff-memless.c
+++ b/drivers/input/ff-memless.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  Force feedback support for memoryless devices
  *
@@ -5,26 +6,11 @@
  *  Copyright (c) 2006 Dmitry Torokhov <dtor@mail.ru>
  */
 
-/*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
 /* #define DEBUG */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/module.h>
@@ -151,7 +137,7 @@ static void ml_schedule_timer(struct ml_device *ml)
 
 	if (!events) {
 		pr_debug("no actions\n");
-		del_timer(&ml->timer);
+		timer_delete(&ml->timer);
 	} else {
 		pr_debug("timer set\n");
 		mod_timer(&ml->timer, earliest);
@@ -237,6 +223,18 @@ static u16 ml_calculate_direction(u16 direction, u16 force,
 		(force + new_force)) << 1;
 }
 
+#define FRAC_N 8
+static inline s16 fixp_new16(s16 a)
+{
+	return ((s32)a) >> (16 - FRAC_N);
+}
+
+static inline s16 fixp_mult(s16 a, s16 b)
+{
+	a = ((s32)a * 0x100) / 0x7fff;
+	return ((s32)(a * b)) >> FRAC_N;
+}
+
 /*
  * Combine two effects and apply gain.
  */
@@ -247,7 +245,7 @@ static void ml_combine_effects(struct ff_effect *effect,
 	struct ff_effect *new = state->effect;
 	unsigned int strong, weak, i;
 	int x, y;
-	fixp_t level;
+	s16 level;
 
 	switch (new->type) {
 	case FF_CONSTANT:
@@ -255,8 +253,8 @@ static void ml_combine_effects(struct ff_effect *effect,
 		level = fixp_new16(apply_envelope(state,
 					new->u.constant.level,
 					&new->u.constant.envelope));
-		x = fixp_mult(fixp_sin(i), level) * gain / 0xffff;
-		y = fixp_mult(-fixp_cos(i), level) * gain / 0xffff;
+		x = fixp_mult(fixp_sin16(i), level) * gain / 0xffff;
+		y = fixp_mult(-fixp_cos16(i), level) * gain / 0xffff;
 		/*
 		 * here we abuse ff_ramp to hold x and y of constant force
 		 * If in future any driver wants something else than x and y
@@ -400,17 +398,15 @@ static void ml_play_effects(struct ml_device *ml)
 	ml_schedule_timer(ml);
 }
 
-static void ml_effect_timer(unsigned long timer_data)
+static void ml_effect_timer(struct timer_list *t)
 {
-	struct input_dev *dev = (struct input_dev *)timer_data;
-	struct ml_device *ml = dev->ff->private;
-	unsigned long flags;
+	struct ml_device *ml = timer_container_of(ml, t, timer);
+	struct input_dev *dev = ml->dev;
 
 	pr_debug("timer: updating effects\n");
 
-	spin_lock_irqsave(&dev->event_lock, flags);
+	guard(spinlock_irqsave)(&dev->event_lock);
 	ml_play_effects(ml);
-	spin_unlock_irqrestore(&dev->event_lock, flags);
 }
 
 /*
@@ -468,7 +464,7 @@ static int ml_ff_upload(struct input_dev *dev,
 	struct ml_device *ml = dev->ff->private;
 	struct ml_effect_state *state = &ml->states[effect->id];
 
-	spin_lock_irq(&dev->event_lock);
+	guard(spinlock_irq)(&dev->event_lock);
 
 	if (test_bit(FF_EFFECT_STARTED, &state->flags)) {
 		__clear_bit(FF_EFFECT_PLAYING, &state->flags);
@@ -480,8 +476,6 @@ static int ml_ff_upload(struct input_dev *dev,
 		ml_schedule_timer(ml);
 	}
 
-	spin_unlock_irq(&dev->event_lock);
-
 	return 0;
 }
 
@@ -489,6 +483,15 @@ static void ml_ff_destroy(struct ff_device *ff)
 {
 	struct ml_device *ml = ff->private;
 
+	/*
+	 * Even though we stop all playing effects when tearing down
+	 * an input device (via input_device_flush() that calls into
+	 * input_ff_flush() that stops and erases all effects), we
+	 * do not actually stop the timer, and therefore we should
+	 * do it here.
+	 */
+	timer_delete_sync(&ml->timer);
+
 	kfree(ml->private);
 }
 
@@ -501,12 +504,11 @@ static void ml_ff_destroy(struct ff_device *ff)
 int input_ff_create_memless(struct input_dev *dev, void *data,
 		int (*play_effect)(struct input_dev *, void *, struct ff_effect *))
 {
-	struct ml_device *ml;
 	struct ff_device *ff;
 	int error;
 	int i;
 
-	ml = kzalloc(sizeof(struct ml_device), GFP_KERNEL);
+	struct ml_device *ml __free(kfree) = kzalloc(sizeof(*ml), GFP_KERNEL);
 	if (!ml)
 		return -ENOMEM;
 
@@ -514,18 +516,15 @@ int input_ff_create_memless(struct input_dev *dev, void *data,
 	ml->private = data;
 	ml->play_effect = play_effect;
 	ml->gain = 0xffff;
-	setup_timer(&ml->timer, ml_effect_timer, (unsigned long)dev);
+	timer_setup(&ml->timer, ml_effect_timer, 0);
 
 	set_bit(FF_GAIN, dev->ffbit);
 
 	error = input_ff_create(dev, FF_MEMLESS_EFFECTS);
-	if (error) {
-		kfree(ml);
+	if (error)
 		return error;
-	}
 
 	ff = dev->ff;
-	ff->private = ml;
 	ff->upload = ml_ff_upload;
 	ff->playback = ml_ff_playback;
 	ff->set_gain = ml_ff_set_gain;
@@ -542,6 +541,8 @@ int input_ff_create_memless(struct input_dev *dev, void *data,
 	for (i = 0; i < FF_MEMLESS_EFFECTS; i++)
 		ml->states[i].effect = &ff->effects[i];
 
+	ff->private = no_free_ptr(ml);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(input_ff_create_memless);