From f4f37c8ec7d2491c8885c890ba74254b9adfbeee Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Sun, 4 Nov 2007 00:41:12 -0400
Subject: [PATCH] Input: Add proper locking when changing device's keymap
Take dev->event_lock to make sure that we don't race with input_event() and
also force key up event when removing a key from keymap table.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
drivers/char/keyboard.c | 4 +--
drivers/input/evdev.c | 6 ++--
drivers/input/input.c | 78 +++++++++++++++++++++++++++++++++++++----
include/linux/input.h | 3 ++
4 files changed, 80 insertions(+), 11 deletions(-)
diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index fc54d234507a..5218d0d0511e 100644
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c
@@ -194,7 +194,7 @@ int getkeycode(unsigned int scancode)
int error = -ENODEV;
list_for_each_entry(handle, &kbd_handler.h_list, h_node) {
- error = handle->dev->getkeycode(handle->dev, scancode, &keycode);
+ error = input_get_keycode(handle->dev, scancode, &keycode);
if (!error)
return keycode;
}
@@ -208,7 +208,7 @@ int setkeycode(unsigned int scancode, unsigned int keycode)
int error = -ENODEV;
list_for_each_entry(handle, &kbd_handler.h_list, h_node) {
- error = handle->dev->setkeycode(handle->dev, scancode, keycode);
+ error = input_set_keycode(handle->dev, scancode, keycode);
if (!error)
break;
}
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index e5b4e9bfbdc5..0727b0a12557 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -617,7 +617,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
if (get_user(t, ip))
return -EFAULT;
- error = dev->getkeycode(dev, t, &v);
+ error = input_get_keycode(dev, t, &v);
if (error)
return error;
@@ -630,7 +630,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
if (get_user(t, ip) || get_user(v, ip + 1))
return -EFAULT;
- return dev->setkeycode(dev, t, v);
+ return input_set_keycode(dev, t, v);
case EVIOCSFF:
if (copy_from_user(&effect, p, sizeof(effect)))
@@ -683,7 +683,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
case EV_SW: bits = dev->swbit; len = SW_MAX; break;
default: return -EINVAL;
- }
+ }
return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
}
diff --git a/drivers/input/input.c b/drivers/input/input.c
index a0be978501ff..e1729e1dd9b2 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -493,7 +493,7 @@ static void input_disconnect_device(struct input_dev *dev)
if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
for (code = 0; code <= KEY_MAX; code++) {
if (is_event_supported(code, dev->keybit, KEY_MAX) &&
- test_bit(code, dev->key)) {
+ __test_and_clear_bit(code, dev->key)) {
input_pass_event(dev, EV_KEY, code, 0);
}
}
@@ -526,7 +526,7 @@ static int input_default_getkeycode(struct input_dev *dev,
if (!dev->keycodesize)
return -EINVAL;
- if (scancode < 0 || scancode >= dev->keycodemax)
+ if (scancode >= dev->keycodemax)
return -EINVAL;
*keycode = input_fetch_keycode(dev, scancode);
@@ -540,10 +540,7 @@ static int input_default_setkeycode(struct input_dev *dev,
int old_keycode;
int i;
- if (scancode < 0 || scancode >= dev->keycodemax)
- return -EINVAL;
-
- if (keycode < 0 || keycode > KEY_MAX)
+ if (scancode >= dev->keycodemax)
return -EINVAL;
if (!dev->keycodesize)
@@ -586,6 +583,75 @@ static int input_default_setkeycode(struct input_dev *dev,
return 0;
}
+/**
+ * input_get_keycode - retrieve keycode currently mapped to a given scancode
+ * @dev: input device which keymap is being queried
+ * @scancode: scancode (or its equivalent for device in question) for which
+ * keycode is needed
+ * @keycode: result
+ *
+ * This function should be called by anyone interested in retrieving current
+ * keymap. Presently keyboard and evdev handlers use it.
+ */
+int input_get_keycode(struct input_dev *dev, int scancode, int *keycode)
+{
+ if (scancode < 0)
+ return -EINVAL;
+
+ return dev->getkeycode(dev, scancode, keycode);
+}
+EXPORT_SYMBOL(input_get_keycode);
+
+/**
+ * input_get_keycode - assign new keycode to a given scancode
+ * @dev: input device which keymap is being updated
+ * @scancode: scancode (or its equivalent for device in question)
+ * @keycode: new keycode to be assigned to the scancode
+ *
+ * This function should be called by anyone needing to update current
+ * keymap. Presently keyboard and evdev handlers use it.
+ */
+int input_set_keycode(struct input_dev *dev, int scancode, int keycode)
+{
+ unsigned long flags;
+ int old_keycode;
+ int retval;
+
+ if (scancode < 0)
+ return -EINVAL;
+
+ if (keycode < 0 || keycode > KEY_MAX)
+ return -EINVAL;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+
+ retval = dev->getkeycode(dev, scancode, &old_keycode);
+ if (retval)
+ goto out;
+
+ retval = dev->setkeycode(dev, scancode, keycode);
+ if (retval)
+ goto out;
+
+ /*
+ * Simulate keyup event if keycode is not present
+ * in the keymap anymore
+ */
+ if (test_bit(EV_KEY, dev->evbit) &&
+ !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
+ __test_and_clear_bit(old_keycode, dev->key)) {
+
+ input_pass_event(dev, EV_KEY, old_keycode, 0);
+ if (dev->sync)
+ input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
+ }
+
+ out:
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+
+ return retval;
+}
+EXPORT_SYMBOL(input_set_keycode);
#define MATCH_BIT(bit, max) \
for (i = 0; i < BITS_TO_LONGS(max); i++) \
diff --git a/include/linux/input.h b/include/linux/input.h
index 2075d6da2a31..9a963fe97300 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -1309,6 +1309,9 @@ static inline void input_set_abs_params(struct input_dev *dev, int axis, int min
dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
}
+int input_get_keycode(struct input_dev *dev, int scancode, int *keycode);
+int input_set_keycode(struct input_dev *dev, int scancode, int keycode);
+
extern struct class input_class;
/**
--
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