diff mbox

[v6,1/1] input: ideapad_slidebar: new input driver

Message ID 520CEE7F.20205@gmail.com
State New, archived
Headers show

Commit Message

Andrey Moiseev Aug. 15, 2013, 3:06 p.m. UTC
v6: fixed things addressed by Dmitry Torokhov to v5 (quoted message goes below the patch)

ideapad_slidebar is a new driver which enables slidebars on some
Lenovo IdeaPad laptops (the slidebars work with SlideNav/Desktop
Navigator under Windows)

Fixes this: https://bugzilla.kernel.org/show_bug.cgi?id=16004

Registers 'IdeaPad Slidebar' input device and
/sys/devices/platform/ideapad_slidebar/input/inputX/slidebar_mode
for switching slidebar's modes.

Now works on:
IdeaPad Y550, Y550P.

May work on (testing and adding new models is needed):
Ideapad Y560, Y460, Y450, Y650,
and, probably, some others.

Driver source: https://github.com/o2genum/ideapad-slidebar.git

Patch is generated against current mainline kernel.

Signed-off-by: Andrey Moiseev <o2g.org.ru@gmail.com>
---
 MAINTAINERS                           |   7 +
 drivers/input/misc/Kconfig            |   9 +
 drivers/input/misc/Makefile           |   1 +
 drivers/input/misc/ideapad_slidebar.c | 348 ++++++++++++++++++++++++++++++++++
 4 files changed, 365 insertions(+)
 create mode 100644 drivers/input/misc/ideapad_slidebar.c

Comments

Dmitry Torokhov Aug. 15, 2013, 4:06 p.m. UTC | #1
Hi Andrey,

On Thu, Aug 15, 2013 at 07:06:39PM +0400, Andrey Moiseev wrote:
> v6: fixed things addressed by Dmitry Torokhov to v5 (quoted message goes below the patch)

Thank you for making chnages, however I have still more comments.

> 
> ideapad_slidebar is a new driver which enables slidebars on some
> Lenovo IdeaPad laptops (the slidebars work with SlideNav/Desktop
> Navigator under Windows)
> 
> Fixes this: https://bugzilla.kernel.org/show_bug.cgi?id=16004
> 
> Registers 'IdeaPad Slidebar' input device and
> /sys/devices/platform/ideapad_slidebar/input/inputX/slidebar_mode
> for switching slidebar's modes.
> 
> Now works on:
> IdeaPad Y550, Y550P.
> 
> May work on (testing and adding new models is needed):
> Ideapad Y560, Y460, Y450, Y650,
> and, probably, some others.
> 
> Driver source: https://github.com/o2genum/ideapad-slidebar.git
> 
> Patch is generated against current mainline kernel.
> 
> Signed-off-by: Andrey Moiseev <o2g.org.ru@gmail.com>
> ---
>  MAINTAINERS                           |   7 +
>  drivers/input/misc/Kconfig            |   9 +
>  drivers/input/misc/Makefile           |   1 +
>  drivers/input/misc/ideapad_slidebar.c | 348 ++++++++++++++++++++++++++++++++++
>  4 files changed, 365 insertions(+)
>  create mode 100644 drivers/input/misc/ideapad_slidebar.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index defc053..2ff3dd8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4096,6 +4096,13 @@ W:	http://launchpad.net/ideapad-laptop
>  S:	Maintained
>  F:	drivers/platform/x86/ideapad-laptop.c
>  
> +IDEAPAD LAPTOP SLIDEBAR DRIVER
> +M:	Andrey Moiseev <o2g.org.ru@gmail.com>
> +L:	linux-input@vger.kernel.org
> +W:	https://github.com/o2genum/ideapad-slidebar
> +S:	Maintained
> +F:	drivers/input/misc/ideapad_slidebar.c
> +
>  IDE/ATAPI DRIVERS
>  M:	Borislav Petkov <bp@alien8.de>
>  L:	linux-ide@vger.kernel.org
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 0b541cd..45729a9 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -647,4 +647,13 @@ config INPUT_SIRFSOC_ONKEY
>  
>  	  If unsure, say N.
>  
> +config INPUT_IDEAPAD_SLIDEBAR
> +	tristate "IdeaPad Laptop Slidebar"
> +	depends on INPUT
> +	help
> +	  Input driver for slidebars on some Lenovo IdeaPad laptops.
> +
> +	  If you have an IdeaPad laptop with a slidebar, say Y or M here.
> +	  Module name is ideapad_slidebar.
> +
>  endif
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index 829de43..0ebfb6d 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -61,3 +61,4 @@ obj-$(CONFIG_INPUT_WISTRON_BTNS)	+= wistron_btns.o
>  obj-$(CONFIG_INPUT_WM831X_ON)		+= wm831x-on.o
>  obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND)	+= xen-kbdfront.o
>  obj-$(CONFIG_INPUT_YEALINK)		+= yealink.o
> +obj-$(CONFIG_INPUT_IDEAPAD_SLIDEBAR)	+= ideapad_slidebar.o
> diff --git a/drivers/input/misc/ideapad_slidebar.c b/drivers/input/misc/ideapad_slidebar.c
> new file mode 100644
> index 0000000..5725d88
> --- /dev/null
> +++ b/drivers/input/misc/ideapad_slidebar.c
> @@ -0,0 +1,348 @@
> +/*
> + * Input driver for slidebars on some Lenovo IdeaPad laptops
> + *
> + * Copyright (C) 2013 Andrey Moiseev <o2g.org.ru@gmail.com>
> + *
> + * Reverse-engineered from Lenovo SlideNav software (SBarHook.dll).
> + *
> + * 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.
> + *
> + * Trademarks are the property of their respective owners.
> + */
> +
> +/*
> + * Currently tested and works on:
> + *	Lenovo IdeaPad Y550
> + *	Lenovo IdeaPad Y550P
> + *
> + * Other models can be added easily. To test,
> + * load with 'force' parameter set 'true'.
> + *
> + * LEDs blinking and input mode are managed via sysfs,
> + * (hex, unsigned byte value):
> + * /sys/devices/platform/ideapad_slidebar/input/inputX/slidebar_mode
> + *
> + * The value is in byte range, however, I only figured out
> + * how bits 0b10011001 work. Some other bits, probably,
> + * are meaningfull too.
> + *
> + * Possible states:
> + *
> + * STD_INT, ONMOV_INT, OFF_INT, LAST_POLL, OFF_POLL
> + *
> + * Meaning:
> + *           released      touched
> + * STD       'heartbeat'   lights follow the finger
> + * ONMOV     no lights     lights follow the finger
> + * LAST      at last pos   lights follow the finger
> + * OFF       no lights     no lights
> + *
> + * INT       all input events are generated, interrupts are used
> + * POLL      no input events by default, to get them,
> + *	     send 0b10000000 (read below)
> + *
> + * Commands: write
> + *
> + * All      |  0b01001 -> STD_INT
> + * possible |  0b10001 -> ONMOV_INT
> + * states   |  0b01000 -> OFF_INT
> + *
> + *                      |  0b0 -> LAST_POLL
> + * STD_INT or ONMOV_INT |
> + *                      |  0b1 -> STD_INT
> + *
> + *                      |  0b0 -> OFF_POLL
> + * OFF_INT or OFF_POLL  |
> + *                      |  0b1 -> OFF_INT
> + *
> + * Any state |   0b10000000 ->  if the slidebar has updated data,
> + *				produce one input event (last position),
> + *				switch to respective POLL mode
> + *				(like 0x0), if not in POLL mode yet.
> + *
> + * Get current state: read
> + *
> + * masked by 0x11 read value means:
> + *
> + * 0x00   LAST
> + * 0x01   STD
> + * 0x10   OFF
> + * 0x11   ONMOV
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/dmi.h>
> +#include <linux/spinlock.h>
> +#include <linux/platform_device.h>
> +#include <linux/input.h>
> +#include <linux/io.h>
> +#include <linux/i8042.h>
> +
> +static bool force;
> +module_param(force, bool, 0);
> +MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
> +
> +static spinlock_t sio_lock = __SPIN_LOCK_UNLOCKED(sio_lock);

static DEFINE_SPINLOCK(sio_lock);

> +
> +static struct input_dev *slidebar_input_dev;
> +static struct platform_device *slidebar_platform_dev;
> +
> +/* Hardware interacting */
> +static unsigned char slidebar_pos_get(void)
> +{
> +	int res;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&sio_lock, flags);
> +	outb(0xf4, 0xff29);
> +	outb(0xbf, 0xff2a);
> +	res = inb(0xff2b);

You are banging on ports but not reserving them.

> +	spin_unlock_irqrestore(&sio_lock, flags);
> +	return res;
> +}
> +
> +static unsigned char slidebar_mode_get(void)
> +{
> +	int res;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&sio_lock, flags);
> +	outb(0xf7, 0xff29);
> +	outb(0x8b, 0xff2a);
> +	res = inb(0xff2b);
> +	spin_unlock_irqrestore(&sio_lock, flags);
> +	return res;
> +}
> +
> +static void slidebar_mode_set(unsigned char mode)
> +{
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&sio_lock, flags);
> +	outb(0xf7, 0xff29);
> +	outb(0x8b, 0xff2a);
> +	outb(mode, 0xff2b);
> +	spin_unlock_irqrestore(&sio_lock, flags);
> +}
> +
> +/* Listening the keyboard (i8042 filter) */
> +static bool slidebar_i8042_filter(unsigned char data, unsigned char str,
> +				struct serio *port)
> +{
> +	static bool extended = false, touched = false;
> +
> +	/* Scancodes: e03b on move, e0bb on release */
> +	if (unlikely(data == 0xe0)) {
> +		extended = true;
> +		return false;
> +	} else if (unlikely(extended && (data == 0x3b))) {
> +		extended = false;
> +		if (!touched)
> +			input_report_key(slidebar_input_dev, BTN_TOUCH, 1);
> +		touched = true;

Input core will filter out duplicate events for you so you do not really
need to do it here.

You probably want something like:

	if (unlikely(extended && (data & 0x3b) == 0x3b)) {
		input_report_key(slidebar_input_dev, BTN_TOUCH, data & 0x80);
		input_report_abs(slidebar_input_dev, ABS_X, slidebar_pos_get());
		input_sync(slidebar_input_dev);
	}


> +		input_report_abs(slidebar_input_dev, ABS_X, slidebar_pos_get());
> +		input_sync(slidebar_input_dev);
> +		return false;
> +	} else if (unlikely(extended && (data == 0xbb))) {
> +		touched = false;
> +		input_report_key(slidebar_input_dev, BTN_TOUCH, 0);
> +		input_sync(slidebar_input_dev);
> +	}
> +	return false;
> +}
> +
> +/* Sysfs slidebar_mode interface */
> +static ssize_t show_slidebar_mode(struct device *dev,
> +				struct device_attribute *attr,
> +				char *buf)
> +{
> +	return sprintf(buf, "%x\n", slidebar_mode_get());
> +}
> +
> +static ssize_t store_slidebar_mode(struct device *dev,
> +				struct device_attribute *attr,
> +				const char *buf, size_t count)
> +{
> +	int mode;
> +
> +	if (!count)
> +		return 0;
> +	if (sscanf(buf, "%x", &mode) != 1)
> +		return -EINVAL;
> +	slidebar_mode_set(mode);
> +	return count;
> +}
> +
> +static DEVICE_ATTR(slidebar_mode, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH,
> +				show_slidebar_mode, store_slidebar_mode);
> +
> +static struct attribute *ideapad_attrs[] = {
> +	&dev_attr_slidebar_mode.attr,
> +	NULL
> +};
> +
> +static struct attribute_group ideapad_attr_group = {
> +	.attrs = ideapad_attrs
> +};
> +
> +static const struct attribute_group *ideapad_attr_groups[] = {
> +	&ideapad_attr_group,
> +	NULL
> +};
> +
> +/* Input device */
> +static int __init setup_input_dev(void)
> +{
> +	int err;
> +
> +	slidebar_input_dev = input_allocate_device();
> +	if (!slidebar_input_dev) {
> +		pr_err("ideapad_slidebar: Not enough memory\n");
> +		return -ENOMEM;
> +	}
> +
> +	slidebar_input_dev->name = "IdeaPad Slidebar";
> +	slidebar_input_dev->id.bustype = BUS_HOST;
> +	slidebar_input_dev->dev.parent = &slidebar_platform_dev->dev;
> +	slidebar_input_dev->dev.groups = ideapad_attr_groups;

This should belong to the platform device, not input device, as I prefer
the latter to be generic and not have any custom attributes.

> +	input_set_capability(slidebar_input_dev, EV_KEY, BTN_TOUCH);
> +	input_set_capability(slidebar_input_dev, EV_ABS, ABS_X);
> +	input_set_abs_params(slidebar_input_dev, ABS_X, 0, 0xff, 0, 0);
> +
> +	err = i8042_install_filter(slidebar_i8042_filter);
> +	if (err) {
> +		pr_err("ideapad_slidebar: Can't install i8042 filter \n");
> +		goto err_free_dev;
> +	}
> +	err = input_register_device(slidebar_input_dev);
> +	if (err) {
> +		pr_err("ideapad_slidebar: Failed to register device\n");
> +		goto err_remove_filter;
> +	}
> +	return 0;
> +
> +err_remove_filter:
> +	i8042_remove_filter(slidebar_i8042_filter);
> +err_free_dev:
> +	input_free_device(slidebar_input_dev);
> +	return err;
> +}
> +
> +static void remove_input_dev(void)
> +{
> +	i8042_remove_filter(slidebar_i8042_filter);
> +	input_unregister_device(slidebar_input_dev);
> +}
> +
> +/* Platform device */
> +static int __init setup_platform_dev(void)
> +{
> +	int err;
> +	slidebar_platform_dev = platform_device_alloc("ideapad_slidebar", -1);
> +	if (!slidebar_platform_dev) {
> +		pr_err("ideapad_slidebar: Not enough memory\n");
> +		return -ENOMEM;
> +	}
> +	err = platform_device_add(slidebar_platform_dev);
> +	if (err) {
> +		pr_err("ideapad_slidebar: Failed to register plarform device\n");
> +		goto err_free_platform_device;
> +	}
> +	return 0;
> +
> +err_free_platform_device:
> +	platform_device_put(slidebar_platform_dev);
> +	return err;
> +}
> +
> +/* Platform driver */
> +static struct platform_driver slidebar_drv = {
> +	.driver = {
> +		.name = "ideapad_slidebar",
> +		.owner = THIS_MODULE,
> +	},
> +};
> +
> +static int __init register_platform_drv(void)
> +{
> +	int err;
> +
> +	err = platform_driver_register(&slidebar_drv);
> +	if (err)
> +		pr_err("ideapad_slidebar: Failed to register platform driver\n");
> +
> +	return err;

I still do not understand why you need these wrappers. I'd get rid of
register_platform_drv(), setup_platform_dev(). BTW, setup_input_dev() and
remove_input_dev() should become probe() and remove() methods of the
platform driver.

> +}
> +
> +/* DMI */
> +static int __init ideapad_dmi_check(const struct dmi_system_id *id)
> +{
> +	pr_info("ideapad_slidebar: Laptop model '%s'\n", id->ident);
> +	return 1;
> +}
> +
> +static const struct dmi_system_id ideapad_dmi[] __initconst = {
> +	{
> +		.ident = "Lenovo IdeaPad Y550",
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "20017"),
> +			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550")
> +		},
> +		.callback = ideapad_dmi_check
> +	},
> +	{
> +		.ident = "Lenovo IdeaPad Y550P",
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "20035"),
> +			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550P")
> +		},
> +		.callback = ideapad_dmi_check
> +	},
> +	{ NULL, }
> +};
> +MODULE_DEVICE_TABLE(dmi, ideapad_dmi);
> +
> +/* Init and cleanup */
> +static int __init slidebar_init(void)
> +{
> +	int err;
> +
> +	if (!force && !dmi_check_system(ideapad_dmi))
> +		return -ENODEV;
> +	err = setup_platform_dev();
> +	if (err)
> +		return err;
> +	err = register_platform_drv();
> +	if (err)
> +		goto err_unregister_platform_dev;
> +	err = setup_input_dev();
> +	if (err)
> +		goto err_unregister_platform_drv;
> +	return 0;
> +
> +err_unregister_platform_drv:
> +	platform_driver_unregister(&slidebar_drv);
> +err_unregister_platform_dev:
> +	platform_device_unregister(slidebar_platform_dev);
> +	return err;
> +}
> +
> +static void __exit slidebar_exit(void)
> +{
> +	remove_input_dev();
> +	platform_device_unregister(slidebar_platform_dev);
> +	platform_driver_unregister(&slidebar_drv);
> +}
> +
> +module_init(slidebar_init);
> +module_exit(slidebar_exit);
> +
> +MODULE_AUTHOR("Andrey Moiseev <o2g.org.ru@gmail.com>");
> +MODULE_DESCRIPTION("Slidebar input support for some Lenovo IdeaPad laptops");
> +MODULE_LICENSE("GPL");
> -- 
> 1.8.3.4

Thanks!
diff mbox

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index defc053..2ff3dd8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4096,6 +4096,13 @@  W:	http://launchpad.net/ideapad-laptop
 S:	Maintained
 F:	drivers/platform/x86/ideapad-laptop.c
 
+IDEAPAD LAPTOP SLIDEBAR DRIVER
+M:	Andrey Moiseev <o2g.org.ru@gmail.com>
+L:	linux-input@vger.kernel.org
+W:	https://github.com/o2genum/ideapad-slidebar
+S:	Maintained
+F:	drivers/input/misc/ideapad_slidebar.c
+
 IDE/ATAPI DRIVERS
 M:	Borislav Petkov <bp@alien8.de>
 L:	linux-ide@vger.kernel.org
diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 0b541cd..45729a9 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -647,4 +647,13 @@  config INPUT_SIRFSOC_ONKEY
 
 	  If unsure, say N.
 
+config INPUT_IDEAPAD_SLIDEBAR
+	tristate "IdeaPad Laptop Slidebar"
+	depends on INPUT
+	help
+	  Input driver for slidebars on some Lenovo IdeaPad laptops.
+
+	  If you have an IdeaPad laptop with a slidebar, say Y or M here.
+	  Module name is ideapad_slidebar.
+
 endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 829de43..0ebfb6d 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -61,3 +61,4 @@  obj-$(CONFIG_INPUT_WISTRON_BTNS)	+= wistron_btns.o
 obj-$(CONFIG_INPUT_WM831X_ON)		+= wm831x-on.o
 obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND)	+= xen-kbdfront.o
 obj-$(CONFIG_INPUT_YEALINK)		+= yealink.o
+obj-$(CONFIG_INPUT_IDEAPAD_SLIDEBAR)	+= ideapad_slidebar.o
diff --git a/drivers/input/misc/ideapad_slidebar.c b/drivers/input/misc/ideapad_slidebar.c
new file mode 100644
index 0000000..5725d88
--- /dev/null
+++ b/drivers/input/misc/ideapad_slidebar.c
@@ -0,0 +1,348 @@ 
+/*
+ * Input driver for slidebars on some Lenovo IdeaPad laptops
+ *
+ * Copyright (C) 2013 Andrey Moiseev <o2g.org.ru@gmail.com>
+ *
+ * Reverse-engineered from Lenovo SlideNav software (SBarHook.dll).
+ *
+ * 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.
+ *
+ * Trademarks are the property of their respective owners.
+ */
+
+/*
+ * Currently tested and works on:
+ *	Lenovo IdeaPad Y550
+ *	Lenovo IdeaPad Y550P
+ *
+ * Other models can be added easily. To test,
+ * load with 'force' parameter set 'true'.
+ *
+ * LEDs blinking and input mode are managed via sysfs,
+ * (hex, unsigned byte value):
+ * /sys/devices/platform/ideapad_slidebar/input/inputX/slidebar_mode
+ *
+ * The value is in byte range, however, I only figured out
+ * how bits 0b10011001 work. Some other bits, probably,
+ * are meaningfull too.
+ *
+ * Possible states:
+ *
+ * STD_INT, ONMOV_INT, OFF_INT, LAST_POLL, OFF_POLL
+ *
+ * Meaning:
+ *           released      touched
+ * STD       'heartbeat'   lights follow the finger
+ * ONMOV     no lights     lights follow the finger
+ * LAST      at last pos   lights follow the finger
+ * OFF       no lights     no lights
+ *
+ * INT       all input events are generated, interrupts are used
+ * POLL      no input events by default, to get them,
+ *	     send 0b10000000 (read below)
+ *
+ * Commands: write
+ *
+ * All      |  0b01001 -> STD_INT
+ * possible |  0b10001 -> ONMOV_INT
+ * states   |  0b01000 -> OFF_INT
+ *
+ *                      |  0b0 -> LAST_POLL
+ * STD_INT or ONMOV_INT |
+ *                      |  0b1 -> STD_INT
+ *
+ *                      |  0b0 -> OFF_POLL
+ * OFF_INT or OFF_POLL  |
+ *                      |  0b1 -> OFF_INT
+ *
+ * Any state |   0b10000000 ->  if the slidebar has updated data,
+ *				produce one input event (last position),
+ *				switch to respective POLL mode
+ *				(like 0x0), if not in POLL mode yet.
+ *
+ * Get current state: read
+ *
+ * masked by 0x11 read value means:
+ *
+ * 0x00   LAST
+ * 0x01   STD
+ * 0x10   OFF
+ * 0x11   ONMOV
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/dmi.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/io.h>
+#include <linux/i8042.h>
+
+static bool force;
+module_param(force, bool, 0);
+MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
+
+static spinlock_t sio_lock = __SPIN_LOCK_UNLOCKED(sio_lock);
+
+static struct input_dev *slidebar_input_dev;
+static struct platform_device *slidebar_platform_dev;
+
+/* Hardware interacting */
+static unsigned char slidebar_pos_get(void)
+{
+	int res;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sio_lock, flags);
+	outb(0xf4, 0xff29);
+	outb(0xbf, 0xff2a);
+	res = inb(0xff2b);
+	spin_unlock_irqrestore(&sio_lock, flags);
+	return res;
+}
+
+static unsigned char slidebar_mode_get(void)
+{
+	int res;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sio_lock, flags);
+	outb(0xf7, 0xff29);
+	outb(0x8b, 0xff2a);
+	res = inb(0xff2b);
+	spin_unlock_irqrestore(&sio_lock, flags);
+	return res;
+}
+
+static void slidebar_mode_set(unsigned char mode)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sio_lock, flags);
+	outb(0xf7, 0xff29);
+	outb(0x8b, 0xff2a);
+	outb(mode, 0xff2b);
+	spin_unlock_irqrestore(&sio_lock, flags);
+}
+
+/* Listening the keyboard (i8042 filter) */
+static bool slidebar_i8042_filter(unsigned char data, unsigned char str,
+				struct serio *port)
+{
+	static bool extended = false, touched = false;
+
+	/* Scancodes: e03b on move, e0bb on release */
+	if (unlikely(data == 0xe0)) {
+		extended = true;
+		return false;
+	} else if (unlikely(extended && (data == 0x3b))) {
+		extended = false;
+		if (!touched)
+			input_report_key(slidebar_input_dev, BTN_TOUCH, 1);
+		touched = true;
+		input_report_abs(slidebar_input_dev, ABS_X, slidebar_pos_get());
+		input_sync(slidebar_input_dev);
+		return false;
+	} else if (unlikely(extended && (data == 0xbb))) {
+		touched = false;
+		input_report_key(slidebar_input_dev, BTN_TOUCH, 0);
+		input_sync(slidebar_input_dev);
+	}
+	return false;
+}
+
+/* Sysfs slidebar_mode interface */
+static ssize_t show_slidebar_mode(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	return sprintf(buf, "%x\n", slidebar_mode_get());
+}
+
+static ssize_t store_slidebar_mode(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	int mode;
+
+	if (!count)
+		return 0;
+	if (sscanf(buf, "%x", &mode) != 1)
+		return -EINVAL;
+	slidebar_mode_set(mode);
+	return count;
+}
+
+static DEVICE_ATTR(slidebar_mode, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH,
+				show_slidebar_mode, store_slidebar_mode);
+
+static struct attribute *ideapad_attrs[] = {
+	&dev_attr_slidebar_mode.attr,
+	NULL
+};
+
+static struct attribute_group ideapad_attr_group = {
+	.attrs = ideapad_attrs
+};
+
+static const struct attribute_group *ideapad_attr_groups[] = {
+	&ideapad_attr_group,
+	NULL
+};
+
+/* Input device */
+static int __init setup_input_dev(void)
+{
+	int err;
+
+	slidebar_input_dev = input_allocate_device();
+	if (!slidebar_input_dev) {
+		pr_err("ideapad_slidebar: Not enough memory\n");
+		return -ENOMEM;
+	}
+
+	slidebar_input_dev->name = "IdeaPad Slidebar";
+	slidebar_input_dev->id.bustype = BUS_HOST;
+	slidebar_input_dev->dev.parent = &slidebar_platform_dev->dev;
+	slidebar_input_dev->dev.groups = ideapad_attr_groups;
+	input_set_capability(slidebar_input_dev, EV_KEY, BTN_TOUCH);
+	input_set_capability(slidebar_input_dev, EV_ABS, ABS_X);
+	input_set_abs_params(slidebar_input_dev, ABS_X, 0, 0xff, 0, 0);
+
+	err = i8042_install_filter(slidebar_i8042_filter);
+	if (err) {
+		pr_err("ideapad_slidebar: Can't install i8042 filter \n");
+		goto err_free_dev;
+	}
+	err = input_register_device(slidebar_input_dev);
+	if (err) {
+		pr_err("ideapad_slidebar: Failed to register device\n");
+		goto err_remove_filter;
+	}
+	return 0;
+
+err_remove_filter:
+	i8042_remove_filter(slidebar_i8042_filter);
+err_free_dev:
+	input_free_device(slidebar_input_dev);
+	return err;
+}
+
+static void remove_input_dev(void)
+{
+	i8042_remove_filter(slidebar_i8042_filter);
+	input_unregister_device(slidebar_input_dev);
+}
+
+/* Platform device */
+static int __init setup_platform_dev(void)
+{
+	int err;
+	slidebar_platform_dev = platform_device_alloc("ideapad_slidebar", -1);
+	if (!slidebar_platform_dev) {
+		pr_err("ideapad_slidebar: Not enough memory\n");
+		return -ENOMEM;
+	}
+	err = platform_device_add(slidebar_platform_dev);
+	if (err) {
+		pr_err("ideapad_slidebar: Failed to register plarform device\n");
+		goto err_free_platform_device;
+	}
+	return 0;
+
+err_free_platform_device:
+	platform_device_put(slidebar_platform_dev);
+	return err;
+}
+
+/* Platform driver */
+static struct platform_driver slidebar_drv = {
+	.driver = {
+		.name = "ideapad_slidebar",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init register_platform_drv(void)
+{
+	int err;
+
+	err = platform_driver_register(&slidebar_drv);
+	if (err)
+		pr_err("ideapad_slidebar: Failed to register platform driver\n");
+
+	return err;
+}
+
+/* DMI */
+static int __init ideapad_dmi_check(const struct dmi_system_id *id)
+{
+	pr_info("ideapad_slidebar: Laptop model '%s'\n", id->ident);
+	return 1;
+}
+
+static const struct dmi_system_id ideapad_dmi[] __initconst = {
+	{
+		.ident = "Lenovo IdeaPad Y550",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "20017"),
+			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550")
+		},
+		.callback = ideapad_dmi_check
+	},
+	{
+		.ident = "Lenovo IdeaPad Y550P",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "20035"),
+			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550P")
+		},
+		.callback = ideapad_dmi_check
+	},
+	{ NULL, }
+};
+MODULE_DEVICE_TABLE(dmi, ideapad_dmi);
+
+/* Init and cleanup */
+static int __init slidebar_init(void)
+{
+	int err;
+
+	if (!force && !dmi_check_system(ideapad_dmi))
+		return -ENODEV;
+	err = setup_platform_dev();
+	if (err)
+		return err;
+	err = register_platform_drv();
+	if (err)
+		goto err_unregister_platform_dev;
+	err = setup_input_dev();
+	if (err)
+		goto err_unregister_platform_drv;
+	return 0;
+
+err_unregister_platform_drv:
+	platform_driver_unregister(&slidebar_drv);
+err_unregister_platform_dev:
+	platform_device_unregister(slidebar_platform_dev);
+	return err;
+}
+
+static void __exit slidebar_exit(void)
+{
+	remove_input_dev();
+	platform_device_unregister(slidebar_platform_dev);
+	platform_driver_unregister(&slidebar_drv);
+}
+
+module_init(slidebar_init);
+module_exit(slidebar_exit);
+
+MODULE_AUTHOR("Andrey Moiseev <o2g.org.ru@gmail.com>");
+MODULE_DESCRIPTION("Slidebar input support for some Lenovo IdeaPad laptops");
+MODULE_LICENSE("GPL");