Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: i8042 - add Lenovo Ideapad U455 to 'reset' blacklist
Input: serio_raw - return proper result when serio_raw_read fails
Input: document device properties
Input: twl4030_keypad - fix comment (trivial)
Input: gpio_keys - fix struct device declared inside parameter list
Input: evdev - fix variable initialisation

Documentation/input/event-codes.txt

···
 class/input/event*/device/capabilities/, and the properties of a device are
 provided in class/input/event*/device/properties.
 
-Types:
-==========
-Types are groupings of codes under a logical input construct. Each type has a
-set of applicable codes to be used in generating events. See the Codes section
-for details on valid codes for each type.
+Event types:
+===========
+Event types are groupings of codes under a logical input construct. Each
+type has a set of applicable codes to be used in generating events. See the
+Codes section for details on valid codes for each type.
 
 * EV_SYN:
   - Used as markers to separate events. Events may be separated in time or in
···
 * EV_FF_STATUS:
   - Used to receive force feedback device status.
 
-Codes:
-==========
-Codes define the precise type of event.
+Event codes:
+===========
+Event codes define the precise type of event.
 
 EV_SYN:
 ----------
···
 EV_PWR events are a special type of event used specifically for power
 mangement. Its usage is not well defined. To be addressed later.
 
+Device properties:
+=================
+Normally, userspace sets up an input device based on the data it emits,
+i.e., the event types. In the case of two devices emitting the same event
+types, additional information can be provided in the form of device
+properties.
+
+INPUT_PROP_DIRECT + INPUT_PROP_POINTER:
+--------------------------------------
+The INPUT_PROP_DIRECT property indicates that device coordinates should be
+directly mapped to screen coordinates (not taking into account trivial
+transformations, such as scaling, flipping and rotating). Non-direct input
+devices require non-trivial transformation, such as absolute to relative
+transformation for touchpads. Typical direct input devices: touchscreens,
+drawing tablets; non-direct devices: touchpads, mice.
+
+The INPUT_PROP_POINTER property indicates that the device is not transposed
+on the screen and thus requires use of an on-screen pointer to trace user's
+movements.  Typical pointer devices: touchpads, tablets, mice; non-pointer
+device: touchscreen.
+
+If neither INPUT_PROP_DIRECT or INPUT_PROP_POINTER are set, the property is
+considered undefined and the device type should be deduced in the
+traditional way, using emitted event types.
+
+INPUT_PROP_BUTTONPAD:
+--------------------
+For touchpads where the button is placed beneath the surface, such that
+pressing down on the pad causes a button click, this property should be
+set. Common in clickpad notebooks and macbooks from 2009 and onwards.
+
+Originally, the buttonpad property was coded into the bcm5974 driver
+version field under the name integrated button. For backwards
+compatibility, both methods need to be checked in userspace.
+
+INPUT_PROP_SEMI_MT:
+------------------
+Some touchpads, most common between 2008 and 2011, can detect the presence
+of multiple contacts without resolving the individual positions; only the
+number of contacts and a rectangular shape is known. For such
+touchpads, the semi-mt property should be set.
+
+Depending on the device, the rectangle may enclose all touches, like a
+bounding box, or just some of them, for instance the two most recent
+touches. The diversity makes the rectangle of limited use, but some
+gestures can normally be extracted from it.
+
+If INPUT_PROP_SEMI_MT is not set, the device is assumed to be a true MT
+device.
+
 Guidelines:
 ==========
 The guidelines below ensure proper single-touch and multi-finger functionality.
···
 BTN_{MOUSE,LEFT,MIDDLE,RIGHT} must not be reported as the result of touch
 contact. BTN_TOOL_<name> events should be reported where possible.
 
+For new hardware, INPUT_PROP_DIRECT should be set.
+
 Trackpads:
 ----------
 Legacy trackpads that only provide relative position information must report
···
 location of the touch. BTN_TOUCH should be used to report when a touch is active
 on the trackpad. Where multi-finger support is available, BTN_TOOL_<name> should
 be used to report the number of touches active on the trackpad.
+
+For new hardware, INPUT_PROP_POINTER should be set.
 
 Tablets:
 ----------
···
 BTN_{0,1,2,etc} are good generic codes for unlabeled buttons. Do not use
 meaningful buttons, like BTN_FORWARD, unless the button is labeled for that
 purpose on the device.
+
+For new hardware, both INPUT_PROP_DIRECT and INPUT_PROP_POINTER should be set.

drivers/input/evdev.c

···
 	struct evdev_client *client = file->private_data;
 	struct evdev *evdev = client->evdev;
 	struct input_event event;
-	int retval;
+	int retval = 0;
 
 	if (count < input_event_size())
 		return -EINVAL;

drivers/input/keyboard/twl4030_keypad.c

···
 #include <linux/i2c/twl.h>
 #include <linux/slab.h>
 
-
 /*
  * The TWL4030 family chips include a keypad controller that supports
  * up to an 8x8 switch matrix.  The controller can issue system wakeup
···
 	if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
 		return -EIO;
 
-	/* Set timeout period to 100 ms */
+	/* Set timeout period to 200 ms */
 	i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
 	if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
 		return -EIO;
···
 MODULE_DESCRIPTION("TWL4030 Keypad Driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:twl4030_keypad");
-

drivers/input/serio/i8042-x86ia64io.h

···
 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 1720"),
 		},
 	},
+	{
+		/* Lenovo Ideapad U455 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "20046"),
+		},
+	},
 	{ }
 };
 

drivers/input/serio/serio_raw.c

···
 	struct serio_raw_client *client = file->private_data;
 	struct serio_raw *serio_raw = client->serio_raw;
 	char uninitialized_var(c);
-	ssize_t retval = 0;
+	ssize_t read = 0;
+	int retval;
 
 	if (serio_raw->dead)
 		return -ENODEV;
···
 	if (serio_raw->dead)
 		return -ENODEV;
 
-	while (retval < count && serio_raw_fetch_byte(serio_raw, &c)) {
-		if (put_user(c, buffer++))
-			return -EFAULT;
-		retval++;
+	while (read < count && serio_raw_fetch_byte(serio_raw, &c)) {
+		if (put_user(c, buffer++)) {
+			retval = -EFAULT;
+			break;
+		}
+		read++;
 	}
 
-	return retval;
+	return read ?: retval;
 }
 
 static ssize_t serio_raw_write(struct file *file, const char __user *buffer,

include/linux/gpio_keys.h

···
 #ifndef _GPIO_KEYS_H
 #define _GPIO_KEYS_H
 
+struct device;
+
 struct gpio_keys_button {
 	/* Configuration parameters */
 	unsigned int code;	/* input event code (KEY_*, SW_*) */