drivers/misc/fujitsu-laptop.c

   1 /*-*-linux-c-*-*/
   2
   3 /*
   4   Copyright (C) 2007 Jonathan Woithe <jwoithe@physics.adelaide.edu.au>
   5   Based on earlier work:
   6     Copyright (C) 2003 Shane Spencer <shane@bogomip.com>
   7     Adrian Yee <brewt-fujitsu@brewt.org>
   8
   9   Templated from msi-laptop.c which is copyright by its respective authors.
  10
  11   This program is free software; you can redistribute it and/or modify
  12   it under the terms of the GNU General Public License as published by
  13   the Free Software Foundation; either version 2 of the License, or
  14   (at your option) any later version.
  15
  16   This program is distributed in the hope that it will be useful, but
  17   WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19   General Public License for more details.
  20
  21   You should have received a copy of the GNU General Public License
  22   along with this program; if not, write to the Free Software
  23   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  24   02110-1301, USA.
  25  */
  26
  27 /*
  28  * fujitsu-laptop.c - Fujitsu laptop support, providing access to additional
  29  * features made available on a range of Fujitsu laptops including the
  30  * P2xxx/P5xxx/S6xxx/S7xxx series.
  31  *
  32  * This driver exports a few files in /sys/devices/platform/fujitsu-laptop/;
  33  * others may be added at a later date.
  34  *
  35  *   lcd_level - Screen brightness: contains a single integer in the
  36  *   range 0..7. (rw)
  37  *
  38  * In addition to these platform device attributes the driver
  39  * registers itself in the Linux backlight control subsystem and is
  40  * available to userspace under /sys/class/backlight/fujitsu-laptop/.
  41  *
  42  * This driver has been tested on a Fujitsu Lifebook S7020.  It should
  43  * work on most P-series and S-series Lifebooks, but YMMV.
  44  */
  45
  46 #include <linux/module.h>
  47 #include <linux/kernel.h>
  48 #include <linux/init.h>
  49 #include <linux/acpi.h>
  50 #include <linux/dmi.h>
  51 #include <linux/backlight.h>
  52 #include <linux/platform_device.h>
  53 #include <linux/autoconf.h>
  54
  55 #define FUJITSU_DRIVER_VERSION "0.3"
  56
  57 #define FUJITSU_LCD_N_LEVELS 8
  58
  59 #define ACPI_FUJITSU_CLASS              "fujitsu"
  60 #define ACPI_FUJITSU_HID                "FUJ02B1"
  61 #define ACPI_FUJITSU_DRIVER_NAME        "Fujitsu laptop FUJ02B1 ACPI extras driver"
  62 #define ACPI_FUJITSU_DEVICE_NAME        "Fujitsu FUJ02B1"
  63
  64 struct fujitsu_t {
  65         acpi_handle acpi_handle;
  66         struct backlight_device *bl_device;
  67         struct platform_device *pf_device;
  68
  69         unsigned long fuj02b1_state;
  70         unsigned int brightness_changed;
  71         unsigned int brightness_level;
  72 };
  73
  74 static struct fujitsu_t *fujitsu;
  75
  76 /* Hardware access */
  77
  78 static int set_lcd_level(int level)
  79 {
  80         acpi_status status = AE_OK;
  81         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
  82         struct acpi_object_list arg_list = { 1, &arg0 };
  83         acpi_handle handle = NULL;
  84
  85         if (level < 0 || level >= FUJITSU_LCD_N_LEVELS)
  86                 return -EINVAL;
  87
  88         if (!fujitsu)
  89                 return -EINVAL;
  90
  91         status = acpi_get_handle(fujitsu->acpi_handle, "SBLL", &handle);
  92         if (ACPI_FAILURE(status)) {
  93                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SBLL not present\n"));
  94                 return -ENODEV;
  95         }
  96
  97         arg0.integer.value = level;
  98
  99         status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
 100         if (ACPI_FAILURE(status))
 101                 return -ENODEV;
 102
 103         return 0;
 104 }
 105
 106 static int get_lcd_level(void)
 107 {
 108         unsigned long state = 0;
 109         acpi_status status = AE_OK;
 110
 111         // Get the Brightness
 112         status =
 113             acpi_evaluate_integer(fujitsu->acpi_handle, "GBLL", NULL, &state);
 114         if (status < 0)
 115                 return status;
 116
 117         fujitsu->fuj02b1_state = state;
 118         fujitsu->brightness_level = state & 0x0fffffff;
 119
 120         if (state & 0x80000000)
 121                 fujitsu->brightness_changed = 1;
 122         else
 123                 fujitsu->brightness_changed = 0;
 124
 125         if (status < 0)
 126                 return status;
 127
 128         return fujitsu->brightness_level;
 129 }
 130
 131 /* Backlight device stuff */
 132
 133 static int bl_get_brightness(struct backlight_device *b)
 134 {
 135         return get_lcd_level();
 136 }
 137
 138 static int bl_update_status(struct backlight_device *b)
 139 {
 140         return set_lcd_level(b->props.brightness);
 141 }
 142
 143 static struct backlight_ops fujitsubl_ops = {
 144         .get_brightness = bl_get_brightness,
 145         .update_status = bl_update_status,
 146 };
 147
 148 /* Platform device */
 149
 150 static ssize_t show_lcd_level(struct device *dev,
 151                               struct device_attribute *attr, char *buf)
 152 {
 153
 154         int ret;
 155
 156         ret = get_lcd_level();
 157         if (ret < 0)
 158                 return ret;
 159
 160         return sprintf(buf, "%i\n", ret);
 161 }
 162
 163 static ssize_t store_lcd_level(struct device *dev,
 164                                struct device_attribute *attr, const char *buf,
 165                                size_t count)
 166 {
 167
 168         int level, ret;
 169
 170         if (sscanf(buf, "%i", &level) != 1
 171             || (level < 0 || level >= FUJITSU_LCD_N_LEVELS))
 172                 return -EINVAL;
 173
 174         ret = set_lcd_level(level);
 175         if (ret < 0)
 176                 return ret;
 177
 178         return count;
 179 }
 180
 181 static DEVICE_ATTR(lcd_level, 0644, show_lcd_level, store_lcd_level);
 182
 183 static struct attribute *fujitsupf_attributes[] = {
 184         &dev_attr_lcd_level.attr,
 185         NULL
 186 };
 187
 188 static struct attribute_group fujitsupf_attribute_group = {
 189         .attrs = fujitsupf_attributes
 190 };
 191
 192 static struct platform_driver fujitsupf_driver = {
 193         .driver = {
 194                    .name = "fujitsu-laptop",
 195                    .owner = THIS_MODULE,
 196                    }
 197 };
 198
 199 /* ACPI device */
 200
 201 int acpi_fujitsu_add(struct acpi_device *device)
 202 {
 203         int result = 0;
 204         int state = 0;
 205
 206         ACPI_FUNCTION_TRACE("acpi_fujitsu_add");
 207
 208         if (!device)
 209                 return -EINVAL;
 210
 211         fujitsu->acpi_handle = device->handle;
 212         sprintf(acpi_device_name(device), "%s", ACPI_FUJITSU_DEVICE_NAME);
 213         sprintf(acpi_device_class(device), "%s", ACPI_FUJITSU_CLASS);
 214         acpi_driver_data(device) = fujitsu;
 215
 216         result = acpi_bus_get_power(fujitsu->acpi_handle, &state);
 217         if (result) {
 218                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 219                                   "Error reading power state\n"));
 220                 goto end;
 221         }
 222
 223         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 224                acpi_device_name(device), acpi_device_bid(device),
 225                !device->power.state ? "on" : "off");
 226
 227       end:
 228
 229         return result;
 230 }
 231
 232 int acpi_fujitsu_remove(struct acpi_device *device, int type)
 233 {
 234         ACPI_FUNCTION_TRACE("acpi_fujitsu_remove");
 235
 236         if (!device || !acpi_driver_data(device))
 237                 return -EINVAL;
 238         fujitsu->acpi_handle = 0;
 239
 240         return 0;
 241 }
 242
 243 static const struct acpi_device_id fujitsu_device_ids[] = {
 244         {ACPI_FUJITSU_HID, 0},
 245         {"", 0},
 246 };
 247
 248 static struct acpi_driver acpi_fujitsu_driver = {
 249         .name = ACPI_FUJITSU_DRIVER_NAME,
 250         .class = ACPI_FUJITSU_CLASS,
 251         .ids = fujitsu_device_ids,
 252         .ops = {
 253                 .add = acpi_fujitsu_add,
 254                 .remove = acpi_fujitsu_remove,
 255                 },
 256 };
 257
 258 /* Initialization */
 259
 260 static int __init fujitsu_init(void)
 261 {
 262         int ret, result;
 263
 264         if (acpi_disabled)
 265                 return -ENODEV;
 266
 267         fujitsu = kmalloc(sizeof(struct fujitsu_t), GFP_KERNEL);
 268         if (!fujitsu)
 269                 return -ENOMEM;
 270         memset(fujitsu, 0, sizeof(struct fujitsu_t));
 271
 272         result = acpi_bus_register_driver(&acpi_fujitsu_driver);
 273         if (result < 0) {
 274                 ret = -ENODEV;
 275                 goto fail_acpi;
 276         }
 277
 278         /* Register backlight stuff */
 279
 280         fujitsu->bl_device =
 281             backlight_device_register("fujitsu-laptop", NULL, NULL,
 282                                       &fujitsubl_ops);
 283         if (IS_ERR(fujitsu->bl_device))
 284                 return PTR_ERR(fujitsu->bl_device);
 285
 286         fujitsu->bl_device->props.max_brightness = FUJITSU_LCD_N_LEVELS - 1;
 287         ret = platform_driver_register(&fujitsupf_driver);
 288         if (ret)
 289                 goto fail_backlight;
 290
 291         /* Register platform stuff */
 292
 293         fujitsu->pf_device = platform_device_alloc("fujitsu-laptop", -1);
 294         if (!fujitsu->pf_device) {
 295                 ret = -ENOMEM;
 296                 goto fail_platform_driver;
 297         }
 298
 299         ret = platform_device_add(fujitsu->pf_device);
 300         if (ret)
 301                 goto fail_platform_device1;
 302
 303         ret =
 304             sysfs_create_group(&fujitsu->pf_device->dev.kobj,
 305                                &fujitsupf_attribute_group);
 306         if (ret)
 307                 goto fail_platform_device2;
 308
 309         printk(KERN_INFO "fujitsu-laptop: driver " FUJITSU_DRIVER_VERSION
 310                " successfully loaded.\n");
 311
 312         return 0;
 313
 314       fail_platform_device2:
 315
 316         platform_device_del(fujitsu->pf_device);
 317
 318       fail_platform_device1:
 319
 320         platform_device_put(fujitsu->pf_device);
 321
 322       fail_platform_driver:
 323
 324         platform_driver_unregister(&fujitsupf_driver);
 325
 326       fail_backlight:
 327
 328         backlight_device_unregister(fujitsu->bl_device);
 329
 330       fail_acpi:
 331
 332         kfree(fujitsu);
 333
 334         return ret;
 335 }
 336
 337 static void __exit fujitsu_cleanup(void)
 338 {
 339         sysfs_remove_group(&fujitsu->pf_device->dev.kobj,
 340                            &fujitsupf_attribute_group);
 341         platform_device_unregister(fujitsu->pf_device);
 342         platform_driver_unregister(&fujitsupf_driver);
 343         backlight_device_unregister(fujitsu->bl_device);
 344
 345         acpi_bus_unregister_driver(&acpi_fujitsu_driver);
 346
 347         kfree(fujitsu);
 348
 349         printk(KERN_INFO "fujitsu-laptop: driver unloaded.\n");
 350 }
 351
 352 module_init(fujitsu_init);
 353 module_exit(fujitsu_cleanup);
 354
 355 MODULE_AUTHOR("Jonathan Woithe");
 356 MODULE_DESCRIPTION("Fujitsu laptop extras support");
 357 MODULE_VERSION(FUJITSU_DRIVER_VERSION);
 358 MODULE_LICENSE("GPL");