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
  54 #define FUJITSU_DRIVER_VERSION "0.3"
  55
  56 #define FUJITSU_LCD_N_LEVELS 8
  57
  58 #define ACPI_FUJITSU_CLASS              "fujitsu"
  59 #define ACPI_FUJITSU_HID                "FUJ02B1"
  60 #define ACPI_FUJITSU_DRIVER_NAME        "Fujitsu laptop FUJ02B1 ACPI extras driver"
  61 #define ACPI_FUJITSU_DEVICE_NAME        "Fujitsu FUJ02B1"
  62
  63 struct fujitsu_t {
  64         acpi_handle acpi_handle;
  65         struct backlight_device *bl_device;
  66         struct platform_device *pf_device;
  67
  68         unsigned long fuj02b1_state;
  69         unsigned int brightness_changed;
  70         unsigned int brightness_level;
  71 };
  72
  73 static struct fujitsu_t *fujitsu;
  74
  75 /* Hardware access */
  76
  77 static int set_lcd_level(int level)
  78 {
  79         acpi_status status = AE_OK;
  80         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
  81         struct acpi_object_list arg_list = { 1, &arg0 };
  82         acpi_handle handle = NULL;
  83
  84         if (level < 0 || level >= FUJITSU_LCD_N_LEVELS)
  85                 return -EINVAL;
  86
  87         if (!fujitsu)
  88                 return -EINVAL;
  89
  90         status = acpi_get_handle(fujitsu->acpi_handle, "SBLL", &handle);
  91         if (ACPI_FAILURE(status)) {
  92                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SBLL not present\n"));
  93                 return -ENODEV;
  94         }
  95
  96         arg0.integer.value = level;
  97
  98         status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
  99         if (ACPI_FAILURE(status))
 100                 return -ENODEV;
 101
 102         return 0;
 103 }
 104
 105 static int get_lcd_level(void)
 106 {
 107         unsigned long state = 0;
 108         acpi_status status = AE_OK;
 109
 110         // Get the Brightness
 111         status =
 112             acpi_evaluate_integer(fujitsu->acpi_handle, "GBLL", NULL, &state);
 113         if (status < 0)
 114                 return status;
 115
 116         fujitsu->fuj02b1_state = state;
 117         fujitsu->brightness_level = state & 0x0fffffff;
 118
 119         if (state & 0x80000000)
 120                 fujitsu->brightness_changed = 1;
 121         else
 122                 fujitsu->brightness_changed = 0;
 123
 124         return fujitsu->brightness_level;
 125 }
 126
 127 /* Backlight device stuff */
 128
 129 static int bl_get_brightness(struct backlight_device *b)
 130 {
 131         return get_lcd_level();
 132 }
 133
 134 static int bl_update_status(struct backlight_device *b)
 135 {
 136         return set_lcd_level(b->props.brightness);
 137 }
 138
 139 static struct backlight_ops fujitsubl_ops = {
 140         .get_brightness = bl_get_brightness,
 141         .update_status = bl_update_status,
 142 };
 143
 144 /* Platform device */
 145
 146 static ssize_t show_lcd_level(struct device *dev,
 147                               struct device_attribute *attr, char *buf)
 148 {
 149
 150         int ret;
 151
 152         ret = get_lcd_level();
 153         if (ret < 0)
 154                 return ret;
 155
 156         return sprintf(buf, "%i\n", ret);
 157 }
 158
 159 static ssize_t store_lcd_level(struct device *dev,
 160                                struct device_attribute *attr, const char *buf,
 161                                size_t count)
 162 {
 163
 164         int level, ret;
 165
 166         if (sscanf(buf, "%i", &level) != 1
 167             || (level < 0 || level >= FUJITSU_LCD_N_LEVELS))
 168                 return -EINVAL;
 169
 170         ret = set_lcd_level(level);
 171         if (ret < 0)
 172                 return ret;
 173
 174         return count;
 175 }
 176
 177 static DEVICE_ATTR(lcd_level, 0644, show_lcd_level, store_lcd_level);
 178
 179 static struct attribute *fujitsupf_attributes[] = {
 180         &dev_attr_lcd_level.attr,
 181         NULL
 182 };
 183
 184 static struct attribute_group fujitsupf_attribute_group = {
 185         .attrs = fujitsupf_attributes
 186 };
 187
 188 static struct platform_driver fujitsupf_driver = {
 189         .driver = {
 190                    .name = "fujitsu-laptop",
 191                    .owner = THIS_MODULE,
 192                    }
 193 };
 194
 195 /* ACPI device */
 196
 197 static int acpi_fujitsu_add(struct acpi_device *device)
 198 {
 199         int result = 0;
 200         int state = 0;
 201
 202         ACPI_FUNCTION_TRACE("acpi_fujitsu_add");
 203
 204         if (!device)
 205                 return -EINVAL;
 206
 207         fujitsu->acpi_handle = device->handle;
 208         sprintf(acpi_device_name(device), "%s", ACPI_FUJITSU_DEVICE_NAME);
 209         sprintf(acpi_device_class(device), "%s", ACPI_FUJITSU_CLASS);
 210         acpi_driver_data(device) = fujitsu;
 211
 212         result = acpi_bus_get_power(fujitsu->acpi_handle, &state);
 213         if (result) {
 214                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 215                                   "Error reading power state\n"));
 216                 goto end;
 217         }
 218
 219         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 220                acpi_device_name(device), acpi_device_bid(device),
 221                !device->power.state ? "on" : "off");
 222
 223       end:
 224
 225         return result;
 226 }
 227
 228 static int acpi_fujitsu_remove(struct acpi_device *device, int type)
 229 {
 230         ACPI_FUNCTION_TRACE("acpi_fujitsu_remove");
 231
 232         if (!device || !acpi_driver_data(device))
 233                 return -EINVAL;
 234         fujitsu->acpi_handle = NULL;
 235
 236         return 0;
 237 }
 238
 239 static const struct acpi_device_id fujitsu_device_ids[] = {
 240         {ACPI_FUJITSU_HID, 0},
 241         {"", 0},
 242 };
 243
 244 static struct acpi_driver acpi_fujitsu_driver = {
 245         .name = ACPI_FUJITSU_DRIVER_NAME,
 246         .class = ACPI_FUJITSU_CLASS,
 247         .ids = fujitsu_device_ids,
 248         .ops = {
 249                 .add = acpi_fujitsu_add,
 250                 .remove = acpi_fujitsu_remove,
 251                 },
 252 };
 253
 254 /* Initialization */
 255
 256 static int __init fujitsu_init(void)
 257 {
 258         int ret, result;
 259
 260         if (acpi_disabled)
 261                 return -ENODEV;
 262
 263         fujitsu = kmalloc(sizeof(struct fujitsu_t), GFP_KERNEL);
 264         if (!fujitsu)
 265                 return -ENOMEM;
 266         memset(fujitsu, 0, sizeof(struct fujitsu_t));
 267
 268         result = acpi_bus_register_driver(&acpi_fujitsu_driver);
 269         if (result < 0) {
 270                 ret = -ENODEV;
 271                 goto fail_acpi;
 272         }
 273
 274         /* Register backlight stuff */
 275
 276         fujitsu->bl_device =
 277             backlight_device_register("fujitsu-laptop", NULL, NULL,
 278                                       &fujitsubl_ops);
 279         if (IS_ERR(fujitsu->bl_device))
 280                 return PTR_ERR(fujitsu->bl_device);
 281
 282         fujitsu->bl_device->props.max_brightness = FUJITSU_LCD_N_LEVELS - 1;
 283         ret = platform_driver_register(&fujitsupf_driver);
 284         if (ret)
 285                 goto fail_backlight;
 286
 287         /* Register platform stuff */
 288
 289         fujitsu->pf_device = platform_device_alloc("fujitsu-laptop", -1);
 290         if (!fujitsu->pf_device) {
 291                 ret = -ENOMEM;
 292                 goto fail_platform_driver;
 293         }
 294
 295         ret = platform_device_add(fujitsu->pf_device);
 296         if (ret)
 297                 goto fail_platform_device1;
 298
 299         ret =
 300             sysfs_create_group(&fujitsu->pf_device->dev.kobj,
 301                                &fujitsupf_attribute_group);
 302         if (ret)
 303                 goto fail_platform_device2;
 304
 305         printk(KERN_INFO "fujitsu-laptop: driver " FUJITSU_DRIVER_VERSION
 306                " successfully loaded.\n");
 307
 308         return 0;
 309
 310       fail_platform_device2:
 311
 312         platform_device_del(fujitsu->pf_device);
 313
 314       fail_platform_device1:
 315
 316         platform_device_put(fujitsu->pf_device);
 317
 318       fail_platform_driver:
 319
 320         platform_driver_unregister(&fujitsupf_driver);
 321
 322       fail_backlight:
 323
 324         backlight_device_unregister(fujitsu->bl_device);
 325
 326       fail_acpi:
 327
 328         kfree(fujitsu);
 329
 330         return ret;
 331 }
 332
 333 static void __exit fujitsu_cleanup(void)
 334 {
 335         sysfs_remove_group(&fujitsu->pf_device->dev.kobj,
 336                            &fujitsupf_attribute_group);
 337         platform_device_unregister(fujitsu->pf_device);
 338         platform_driver_unregister(&fujitsupf_driver);
 339         backlight_device_unregister(fujitsu->bl_device);
 340
 341         acpi_bus_unregister_driver(&acpi_fujitsu_driver);
 342
 343         kfree(fujitsu);
 344
 345         printk(KERN_INFO "fujitsu-laptop: driver unloaded.\n");
 346 }
 347
 348 module_init(fujitsu_init);
 349 module_exit(fujitsu_cleanup);
 350
 351 MODULE_AUTHOR("Jonathan Woithe");
 352 MODULE_DESCRIPTION("Fujitsu laptop extras support");
 353 MODULE_VERSION(FUJITSU_DRIVER_VERSION);
 354 MODULE_LICENSE("GPL");