linux/drivers/input/misc/ideapad_slidebar.c
<<
>>
Prefs
   1/*
   2 * Input driver for slidebars on some Lenovo IdeaPad laptops
   3 *
   4 * Copyright (C) 2013 Andrey Moiseev <o2g.org.ru@gmail.com>
   5 *
   6 * Reverse-engineered from Lenovo SlideNav software (SBarHook.dll).
   7 *
   8 * This program is free software; you can redistribute it and/or modify it
   9 * under the terms of the GNU General Public License as published by the Free
  10 * Software Foundation; either version 2 of the License, or (at your option)
  11 * any later version.
  12 *
  13 * Trademarks are the property of their respective owners.
  14 */
  15
  16/*
  17 * Currently tested and works on:
  18 *      Lenovo IdeaPad Y550
  19 *      Lenovo IdeaPad Y550P
  20 *
  21 * Other models can be added easily. To test,
  22 * load with 'force' parameter set 'true'.
  23 *
  24 * LEDs blinking and input mode are managed via sysfs,
  25 * (hex, unsigned byte value):
  26 * /sys/devices/platform/ideapad_slidebar/slidebar_mode
  27 *
  28 * The value is in byte range, however, I only figured out
  29 * how bits 0b10011001 work. Some other bits, probably,
  30 * are meaningfull too.
  31 *
  32 * Possible states:
  33 *
  34 * STD_INT, ONMOV_INT, OFF_INT, LAST_POLL, OFF_POLL
  35 *
  36 * Meaning:
  37 *           released      touched
  38 * STD       'heartbeat'   lights follow the finger
  39 * ONMOV     no lights     lights follow the finger
  40 * LAST      at last pos   lights follow the finger
  41 * OFF       no lights     no lights
  42 *
  43 * INT       all input events are generated, interrupts are used
  44 * POLL      no input events by default, to get them,
  45 *           send 0b10000000 (read below)
  46 *
  47 * Commands: write
  48 *
  49 * All      |  0b01001 -> STD_INT
  50 * possible |  0b10001 -> ONMOV_INT
  51 * states   |  0b01000 -> OFF_INT
  52 *
  53 *                      |  0b0 -> LAST_POLL
  54 * STD_INT or ONMOV_INT |
  55 *                      |  0b1 -> STD_INT
  56 *
  57 *                      |  0b0 -> OFF_POLL
  58 * OFF_INT or OFF_POLL  |
  59 *                      |  0b1 -> OFF_INT
  60 *
  61 * Any state |   0b10000000 ->  if the slidebar has updated data,
  62 *                              produce one input event (last position),
  63 *                              switch to respective POLL mode
  64 *                              (like 0x0), if not in POLL mode yet.
  65 *
  66 * Get current state: read
  67 *
  68 * masked by 0x11 read value means:
  69 *
  70 * 0x00   LAST
  71 * 0x01   STD
  72 * 0x10   OFF
  73 * 0x11   ONMOV
  74 */
  75
  76#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  77
  78#include <linux/module.h>
  79#include <linux/kernel.h>
  80#include <linux/dmi.h>
  81#include <linux/spinlock.h>
  82#include <linux/platform_device.h>
  83#include <linux/input.h>
  84#include <linux/io.h>
  85#include <linux/ioport.h>
  86#include <linux/i8042.h>
  87#include <linux/serio.h>
  88
  89#define IDEAPAD_BASE    0xff29
  90
  91static bool force;
  92module_param(force, bool, 0);
  93MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
  94
  95static DEFINE_SPINLOCK(io_lock);
  96
  97static struct input_dev *slidebar_input_dev;
  98static struct platform_device *slidebar_platform_dev;
  99
 100static u8 slidebar_pos_get(void)
 101{
 102        u8 res;
 103        unsigned long flags;
 104
 105        spin_lock_irqsave(&io_lock, flags);
 106        outb(0xf4, 0xff29);
 107        outb(0xbf, 0xff2a);
 108        res = inb(0xff2b);
 109        spin_unlock_irqrestore(&io_lock, flags);
 110
 111        return res;
 112}
 113
 114static u8 slidebar_mode_get(void)
 115{
 116        u8 res;
 117        unsigned long flags;
 118
 119        spin_lock_irqsave(&io_lock, flags);
 120        outb(0xf7, 0xff29);
 121        outb(0x8b, 0xff2a);
 122        res = inb(0xff2b);
 123        spin_unlock_irqrestore(&io_lock, flags);
 124
 125        return res;
 126}
 127
 128static void slidebar_mode_set(u8 mode)
 129{
 130        unsigned long flags;
 131
 132        spin_lock_irqsave(&io_lock, flags);
 133        outb(0xf7, 0xff29);
 134        outb(0x8b, 0xff2a);
 135        outb(mode, 0xff2b);
 136        spin_unlock_irqrestore(&io_lock, flags);
 137}
 138
 139static bool slidebar_i8042_filter(unsigned char data, unsigned char str,
 140                                  struct serio *port)
 141{
 142        static bool extended = false;
 143
 144        /* We are only interested in data coming form KBC port */
 145        if (str & I8042_STR_AUXDATA)
 146                return false;
 147
 148        /* Scancodes: e03b on move, e0bb on release. */
 149        if (data == 0xe0) {
 150                extended = true;
 151                return true;
 152        }
 153
 154        if (!extended)
 155                return false;
 156
 157        extended = false;
 158
 159        if (likely((data & 0x7f) != 0x3b)) {
 160                serio_interrupt(port, 0xe0, 0);
 161                return false;
 162        }
 163
 164        if (data & 0x80) {
 165                input_report_key(slidebar_input_dev, BTN_TOUCH, 0);
 166        } else {
 167                input_report_key(slidebar_input_dev, BTN_TOUCH, 1);
 168                input_report_abs(slidebar_input_dev, ABS_X, slidebar_pos_get());
 169        }
 170        input_sync(slidebar_input_dev);
 171
 172        return true;
 173}
 174
 175static ssize_t show_slidebar_mode(struct device *dev,
 176                                  struct device_attribute *attr,
 177                                  char *buf)
 178{
 179        return sprintf(buf, "%x\n", slidebar_mode_get());
 180}
 181
 182static ssize_t store_slidebar_mode(struct device *dev,
 183                                   struct device_attribute *attr,
 184                                   const char *buf, size_t count)
 185{
 186        u8 mode;
 187        int error;
 188
 189        error = kstrtou8(buf, 0, &mode);
 190        if (error)
 191                return error;
 192
 193        slidebar_mode_set(mode);
 194
 195        return count;
 196}
 197
 198static DEVICE_ATTR(slidebar_mode, S_IWUSR | S_IRUGO,
 199                   show_slidebar_mode, store_slidebar_mode);
 200
 201static struct attribute *ideapad_attrs[] = {
 202        &dev_attr_slidebar_mode.attr,
 203        NULL
 204};
 205
 206static struct attribute_group ideapad_attr_group = {
 207        .attrs = ideapad_attrs
 208};
 209
 210static const struct attribute_group *ideapad_attr_groups[] = {
 211        &ideapad_attr_group,
 212        NULL
 213};
 214
 215static int __init ideapad_probe(struct platform_device* pdev)
 216{
 217        int err;
 218
 219        if (!request_region(IDEAPAD_BASE, 3, "ideapad_slidebar")) {
 220                dev_err(&pdev->dev, "IO ports are busy\n");
 221                return -EBUSY;
 222        }
 223
 224        slidebar_input_dev = input_allocate_device();
 225        if (!slidebar_input_dev) {
 226                dev_err(&pdev->dev, "Failed to allocate input device\n");
 227                err = -ENOMEM;
 228                goto err_release_ports;
 229        }
 230
 231        slidebar_input_dev->name = "IdeaPad Slidebar";
 232        slidebar_input_dev->id.bustype = BUS_HOST;
 233        slidebar_input_dev->dev.parent = &pdev->dev;
 234        input_set_capability(slidebar_input_dev, EV_KEY, BTN_TOUCH);
 235        input_set_capability(slidebar_input_dev, EV_ABS, ABS_X);
 236        input_set_abs_params(slidebar_input_dev, ABS_X, 0, 0xff, 0, 0);
 237
 238        err = i8042_install_filter(slidebar_i8042_filter);
 239        if (err) {
 240                dev_err(&pdev->dev,
 241                        "Failed to install i8042 filter: %d\n", err);
 242                goto err_free_dev;
 243        }
 244
 245        err = input_register_device(slidebar_input_dev);
 246        if (err) {
 247                dev_err(&pdev->dev,
 248                        "Failed to register input device: %d\n", err);
 249                goto err_remove_filter;
 250        }
 251
 252        return 0;
 253
 254err_remove_filter:
 255        i8042_remove_filter(slidebar_i8042_filter);
 256err_free_dev:
 257        input_free_device(slidebar_input_dev);
 258err_release_ports:
 259        release_region(IDEAPAD_BASE, 3);
 260        return err;
 261}
 262
 263static int ideapad_remove(struct platform_device *pdev)
 264{
 265        i8042_remove_filter(slidebar_i8042_filter);
 266        input_unregister_device(slidebar_input_dev);
 267        release_region(IDEAPAD_BASE, 3);
 268
 269        return 0;
 270}
 271
 272static struct platform_driver slidebar_drv = {
 273        .driver = {
 274                .name = "ideapad_slidebar",
 275        },
 276        .remove = ideapad_remove,
 277};
 278
 279static int __init ideapad_dmi_check(const struct dmi_system_id *id)
 280{
 281        pr_info("Laptop model '%s'\n", id->ident);
 282        return 1;
 283}
 284
 285static const struct dmi_system_id ideapad_dmi[] __initconst = {
 286        {
 287                .ident = "Lenovo IdeaPad Y550",
 288                .matches = {
 289                        DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 290                        DMI_MATCH(DMI_PRODUCT_NAME, "20017"),
 291                        DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550")
 292                },
 293                .callback = ideapad_dmi_check
 294        },
 295        {
 296                .ident = "Lenovo IdeaPad Y550P",
 297                .matches = {
 298                        DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 299                        DMI_MATCH(DMI_PRODUCT_NAME, "20035"),
 300                        DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y550P")
 301                },
 302                .callback = ideapad_dmi_check
 303        },
 304        { NULL, }
 305};
 306MODULE_DEVICE_TABLE(dmi, ideapad_dmi);
 307
 308static int __init slidebar_init(void)
 309{
 310        int err;
 311
 312        if (!force && !dmi_check_system(ideapad_dmi)) {
 313                pr_err("DMI does not match\n");
 314                return -ENODEV;
 315        }
 316
 317        slidebar_platform_dev = platform_device_alloc("ideapad_slidebar", -1);
 318        if (!slidebar_platform_dev) {
 319                pr_err("Not enough memory\n");
 320                return -ENOMEM;
 321        }
 322
 323        slidebar_platform_dev->dev.groups = ideapad_attr_groups;
 324
 325        err = platform_device_add(slidebar_platform_dev);
 326        if (err) {
 327                pr_err("Failed to register platform device\n");
 328                goto err_free_dev;
 329        }
 330
 331        err = platform_driver_probe(&slidebar_drv, ideapad_probe);
 332        if (err) {
 333                pr_err("Failed to register platform driver\n");
 334                goto err_delete_dev;
 335        }
 336
 337        return 0;
 338
 339err_delete_dev:
 340        platform_device_del(slidebar_platform_dev);
 341err_free_dev:
 342        platform_device_put(slidebar_platform_dev);
 343        return err;
 344}
 345
 346static void __exit slidebar_exit(void)
 347{
 348        platform_device_unregister(slidebar_platform_dev);
 349        platform_driver_unregister(&slidebar_drv);
 350}
 351
 352module_init(slidebar_init);
 353module_exit(slidebar_exit);
 354
 355MODULE_AUTHOR("Andrey Moiseev <o2g.org.ru@gmail.com>");
 356MODULE_DESCRIPTION("Slidebar input support for some Lenovo IdeaPad laptops");
 357MODULE_LICENSE("GPL");
 358