drivers/input/misc/ideapad_slidebar.c

   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
  91 static bool force;
  92 module_param(force, bool, 0);
  93 MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
  94
  95 static DEFINE_SPINLOCK(io_lock);
  96
  97 static struct input_dev *slidebar_input_dev;
  98 static struct platform_device *slidebar_platform_dev;
  99
 100 static 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
 114 static 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
 128 static 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
 139 static 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
 175 static 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
 182 static 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
 198 static DEVICE_ATTR(slidebar_mode, S_IWUSR | S_IRUGO,
 199                    show_slidebar_mode, store_slidebar_mode);
 200
 201 static struct attribute *ideapad_attrs[] = {
 202         &dev_attr_slidebar_mode.attr,
 203         NULL
 204 };
 205
 206 static struct attribute_group ideapad_attr_group = {
 207         .attrs = ideapad_attrs
 208 };
 209
 210 static const struct attribute_group *ideapad_attr_groups[] = {
 211         &ideapad_attr_group,
 212         NULL
 213 };
 214
 215 static 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
 254 err_remove_filter:
 255         i8042_remove_filter(slidebar_i8042_filter);
 256 err_free_dev:
 257         input_free_device(slidebar_input_dev);
 258 err_release_ports:
 259         release_region(IDEAPAD_BASE, 3);
 260         return err;
 261 }
 262
 263 static 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
 272 static struct platform_driver slidebar_drv = {
 273         .driver = {
 274                 .name = "ideapad_slidebar",
 275         },
 276         .remove = ideapad_remove,
 277 };
 278
 279 static 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
 285 static 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 };
 306 MODULE_DEVICE_TABLE(dmi, ideapad_dmi);
 307
 308 static 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
 339 err_delete_dev:
 340         platform_device_del(slidebar_platform_dev);
 341 err_free_dev:
 342         platform_device_put(slidebar_platform_dev);
 343         return err;
 344 }
 345
 346 static void __exit slidebar_exit(void)
 347 {
 348         platform_device_unregister(slidebar_platform_dev);
 349         platform_driver_unregister(&slidebar_drv);
 350 }
 351
 352 module_init(slidebar_init);
 353 module_exit(slidebar_exit);
 354
 355 MODULE_AUTHOR("Andrey Moiseev <o2g.org.ru@gmail.com>");
 356 MODULE_DESCRIPTION("Slidebar input support for some Lenovo IdeaPad laptops");
 357 MODULE_LICENSE("GPL");