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         return fujitsu->brightness_level;
 126 }
 127
 128 /* Backlight device stuff */
 129
 130 static int bl_get_brightness(struct backlight_device *b)
 131 {
 132         return get_lcd_level();
 133 }
 134
 135 static int bl_update_status(struct backlight_device *b)
 136 {
 137         return set_lcd_level(b->props.brightness);
 138 }
 139
 140 static struct backlight_ops fujitsubl_ops = {
 141         .get_brightness = bl_get_brightness,
 142         .update_status = bl_update_status,
 143 };
 144
 145 /* Platform device */
 146
 147 static ssize_t show_lcd_level(struct device *dev,
 148                               struct device_attribute *attr, char *buf)
 149 {
 150
 151         int ret;
 152
 153         ret = get_lcd_level();
 154         if (ret < 0)
 155                 return ret;
 156
 157         return sprintf(buf, "%i\n", ret);
 158 }
 159
 160 static ssize_t store_lcd_level(struct device *dev,
 161                                struct device_attribute *attr, const char *buf,
 162                                size_t count)
 163 {
 164
 165         int level, ret;
 166
 167         if (sscanf(buf, "%i", &level) != 1
 168             || (level < 0 || level >= FUJITSU_LCD_N_LEVELS))
 169                 return -EINVAL;
 170
 171         ret = set_lcd_level(level);
 172         if (ret < 0)
 173                 return ret;
 174
 175         return count;
 176 }
 177
 178 static DEVICE_ATTR(lcd_level, 0644, show_lcd_level, store_lcd_level);
 179
 180 static struct attribute *fujitsupf_attributes[] = {
 181         &dev_attr_lcd_level.attr,
 182         NULL
 183 };
 184
 185 static struct attribute_group fujitsupf_attribute_group = {
 186         .attrs = fujitsupf_attributes
 187 };
 188
 189 static struct platform_driver fujitsupf_driver = {
 190         .driver = {
 191                    .name = "fujitsu-laptop",
 192                    .owner = THIS_MODULE,
 193                    }
 194 };
 195
 196 /* ACPI device */
 197
 198 static int acpi_fujitsu_add(struct acpi_device *device)
 199 {
 200         int result = 0;
 201         int state = 0;
 202
 203         ACPI_FUNCTION_TRACE("acpi_fujitsu_add");
 204
 205         if (!device)
 206                 return -EINVAL;
 207
 208         fujitsu->acpi_handle = device->handle;
 209         sprintf(acpi_device_name(device), "%s", ACPI_FUJITSU_DEVICE_NAME);
 210         sprintf(acpi_device_class(device), "%s", ACPI_FUJITSU_CLASS);
 211         acpi_driver_data(device) = fujitsu;
 212
 213         result = acpi_bus_get_power(fujitsu->acpi_handle, &state);
 214         if (result) {
 215                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 216                                   "Error reading power state\n"));
 217                 goto end;
 218         }
 219
 220         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 221                acpi_device_name(device), acpi_device_bid(device),
 222                !device->power.state ? "on" : "off");
 223
 224       end:
 225
 226         return result;
 227 }
 228
 229 static int acpi_fujitsu_remove(struct acpi_device *device, int type)
 230 {
 231         ACPI_FUNCTION_TRACE("acpi_fujitsu_remove");
 232
 233         if (!device || !acpi_driver_data(device))
 234                 return -EINVAL;
 235         fujitsu->acpi_handle = 0;
 236
 237         return 0;
 238 }
 239
 240 static const struct acpi_device_id fujitsu_device_ids[] = {
 241         {ACPI_FUJITSU_HID, 0},
 242         {"", 0},
 243 };
 244
 245 static struct acpi_driver acpi_fujitsu_driver = {
 246         .name = ACPI_FUJITSU_DRIVER_NAME,
 247         .class = ACPI_FUJITSU_CLASS,
 248         .ids = fujitsu_device_ids,
 249         .ops = {
 250                 .add = acpi_fujitsu_add,
 251                 .remove = acpi_fujitsu_remove,
 252                 },
 253 };
 254
 255 /* Initialization */
 256
 257 static int __init fujitsu_init(void)
 258 {
 259         int ret, result;
 260
 261         if (acpi_disabled)
 262                 return -ENODEV;
 263
 264         fujitsu = kmalloc(sizeof(struct fujitsu_t), GFP_KERNEL);
 265         if (!fujitsu)
 266                 return -ENOMEM;
 267         memset(fujitsu, 0, sizeof(struct fujitsu_t));
 268
 269         result = acpi_bus_register_driver(&acpi_fujitsu_driver);
 270         if (result < 0) {
 271                 ret = -ENODEV;
 272                 goto fail_acpi;
 273         }
 274
 275         /* Register backlight stuff */
 276
 277         fujitsu->bl_device =
 278             backlight_device_register("fujitsu-laptop", NULL, NULL,
 279                                       &fujitsubl_ops);
 280         if (IS_ERR(fujitsu->bl_device))
 281                 return PTR_ERR(fujitsu->bl_device);
 282
 283         fujitsu->bl_device->props.max_brightness = FUJITSU_LCD_N_LEVELS - 1;
 284         ret = platform_driver_register(&fujitsupf_driver);
 285         if (ret)
 286                 goto fail_backlight;
 287
 288         /* Register platform stuff */
 289
 290         fujitsu->pf_device = platform_device_alloc("fujitsu-laptop", -1);
 291         if (!fujitsu->pf_device) {
 292                 ret = -ENOMEM;
 293                 goto fail_platform_driver;
 294         }
 295
 296         ret = platform_device_add(fujitsu->pf_device);
 297         if (ret)
 298                 goto fail_platform_device1;
 299
 300         ret =
 301             sysfs_create_group(&fujitsu->pf_device->dev.kobj,
 302                                &fujitsupf_attribute_group);
 303         if (ret)
 304                 goto fail_platform_device2;
 305
 306         printk(KERN_INFO "fujitsu-laptop: driver " FUJITSU_DRIVER_VERSION
 307                " successfully loaded.\n");
 308
 309         return 0;
 310
 311       fail_platform_device2:
 312
 313         platform_device_del(fujitsu->pf_device);
 314
 315       fail_platform_device1:
 316
 317         platform_device_put(fujitsu->pf_device);
 318
 319       fail_platform_driver:
 320
 321         platform_driver_unregister(&fujitsupf_driver);
 322
 323       fail_backlight:
 324
 325         backlight_device_unregister(fujitsu->bl_device);
 326
 327       fail_acpi:
 328
 329         kfree(fujitsu);
 330
 331         return ret;
 332 }
 333
 334 static void __exit fujitsu_cleanup(void)
 335 {
 336         sysfs_remove_group(&fujitsu->pf_device->dev.kobj,
 337                            &fujitsupf_attribute_group);
 338         platform_device_unregister(fujitsu->pf_device);
 339         platform_driver_unregister(&fujitsupf_driver);
 340         backlight_device_unregister(fujitsu->bl_device);
 341
 342         acpi_bus_unregister_driver(&acpi_fujitsu_driver);
 343
 344         kfree(fujitsu);
 345
 346         printk(KERN_INFO "fujitsu-laptop: driver unloaded.\n");
 347 }
 348
 349 module_init(fujitsu_init);
 350 module_exit(fujitsu_cleanup);
 351
 352 MODULE_AUTHOR("Jonathan Woithe");
 353 MODULE_DESCRIPTION("Fujitsu laptop extras support");
 354 MODULE_VERSION(FUJITSU_DRIVER_VERSION);
 355 MODULE_LICENSE("GPL");