drivers/platform/x86/intel_oaktrail.c

   1 /*
   2  * intel_oaktrail.c - Intel OakTrail Platform support.
   3  *
   4  * Copyright (C) 2010-2011 Intel Corporation
   5  * Author: Yin Kangkai (kangkai.yin@intel.com)
   6  *
   7  * based on Compal driver, Copyright (C) 2008 Cezary Jackiewicz
   8  * <cezary.jackiewicz (at) gmail.com>, based on MSI driver
   9  * Copyright (C) 2006 Lennart Poettering <mzxreary (at) 0pointer (dot) de>
  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  * This driver does below things:
  27  * 1. registers itself in the Linux backlight control in
  28  *    /sys/class/backlight/intel_oaktrail/
  29  *
  30  * 2. registers in the rfkill subsystem here: /sys/class/rfkill/rfkillX/
  31  *    for these components: wifi, bluetooth, wwan (3g), gps
  32  *
  33  * This driver might work on other products based on Oaktrail. If you
  34  * want to try it you can pass force=1 as argument to the module which
  35  * will force it to load even when the DMI data doesn't identify the
  36  * product as compatible.
  37  */
  38
  39 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  40
  41 #include <linux/module.h>
  42 #include <linux/kernel.h>
  43 #include <linux/init.h>
  44 #include <linux/acpi.h>
  45 #include <linux/fb.h>
  46 #include <linux/mutex.h>
  47 #include <linux/err.h>
  48 #include <linux/i2c.h>
  49 #include <linux/backlight.h>
  50 #include <linux/platform_device.h>
  51 #include <linux/dmi.h>
  52 #include <linux/rfkill.h>
  53 #include <acpi/acpi_bus.h>
  54 #include <acpi/acpi_drivers.h>
  55
  56
  57 #define DRIVER_NAME     "intel_oaktrail"
  58 #define DRIVER_VERSION  "0.4ac1"
  59
  60 /*
  61  * This is the devices status address in EC space, and the control bits
  62  * definition:
  63  *
  64  * (1 << 0):    Camera enable/disable, RW.
  65  * (1 << 1):    Bluetooth enable/disable, RW.
  66  * (1 << 2):    GPS enable/disable, RW.
  67  * (1 << 3):    WiFi enable/disable, RW.
  68  * (1 << 4):    WWAN (3G) enable/disalbe, RW.
  69  * (1 << 5):    Touchscreen enable/disable, Read Only.
  70  */
  71 #define OT_EC_DEVICE_STATE_ADDRESS      0xD6
  72
  73 #define OT_EC_CAMERA_MASK       (1 << 0)
  74 #define OT_EC_BT_MASK           (1 << 1)
  75 #define OT_EC_GPS_MASK          (1 << 2)
  76 #define OT_EC_WIFI_MASK         (1 << 3)
  77 #define OT_EC_WWAN_MASK         (1 << 4)
  78 #define OT_EC_TS_MASK           (1 << 5)
  79
  80 /*
  81  * This is the address in EC space and commands used to control LCD backlight:
  82  *
  83  * Two steps needed to change the LCD backlight:
  84  *   1. write the backlight percentage into OT_EC_BL_BRIGHTNESS_ADDRESS;
  85  *   2. write OT_EC_BL_CONTROL_ON_DATA into OT_EC_BL_CONTROL_ADDRESS.
  86  *
  87  * To read the LCD back light, just read out the value from
  88  * OT_EC_BL_BRIGHTNESS_ADDRESS.
  89  *
  90  * LCD backlight brightness range: 0 - 100 (OT_EC_BL_BRIGHTNESS_MAX)
  91  */
  92 #define OT_EC_BL_BRIGHTNESS_ADDRESS     0x44
  93 #define OT_EC_BL_BRIGHTNESS_MAX         100
  94 #define OT_EC_BL_CONTROL_ADDRESS        0x3A
  95 #define OT_EC_BL_CONTROL_ON_DATA        0x1A
  96
  97
  98 static bool force;
  99 module_param(force, bool, 0);
 100 MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
 101
 102 static struct platform_device *oaktrail_device;
 103 static struct backlight_device *oaktrail_bl_device;
 104 static struct rfkill *bt_rfkill;
 105 static struct rfkill *gps_rfkill;
 106 static struct rfkill *wifi_rfkill;
 107 static struct rfkill *wwan_rfkill;
 108
 109
 110 /* rfkill */
 111 static int oaktrail_rfkill_set(void *data, bool blocked)
 112 {
 113         u8 value;
 114         u8 result;
 115         unsigned long radio = (unsigned long) data;
 116
 117         ec_read(OT_EC_DEVICE_STATE_ADDRESS, &result);
 118
 119         if (!blocked)
 120                 value = (u8) (result | radio);
 121         else
 122                 value = (u8) (result & ~radio);
 123
 124         ec_write(OT_EC_DEVICE_STATE_ADDRESS, value);
 125
 126         return 0;
 127 }
 128
 129 static const struct rfkill_ops oaktrail_rfkill_ops = {
 130         .set_block = oaktrail_rfkill_set,
 131 };
 132
 133 static struct rfkill *oaktrail_rfkill_new(char *name, enum rfkill_type type,
 134                                           unsigned long mask)
 135 {
 136         struct rfkill *rfkill_dev;
 137         u8 value;
 138         int err;
 139
 140         rfkill_dev = rfkill_alloc(name, &oaktrail_device->dev, type,
 141                                   &oaktrail_rfkill_ops, (void *)mask);
 142         if (!rfkill_dev)
 143                 return ERR_PTR(-ENOMEM);
 144
 145         ec_read(OT_EC_DEVICE_STATE_ADDRESS, &value);
 146         rfkill_init_sw_state(rfkill_dev, (value & mask) != 1);
 147
 148         err = rfkill_register(rfkill_dev);
 149         if (err) {
 150                 rfkill_destroy(rfkill_dev);
 151                 return ERR_PTR(err);
 152         }
 153
 154         return rfkill_dev;
 155 }
 156
 157 static inline void __oaktrail_rfkill_cleanup(struct rfkill *rf)
 158 {
 159         if (rf) {
 160                 rfkill_unregister(rf);
 161                 rfkill_destroy(rf);
 162         }
 163 }
 164
 165 static void oaktrail_rfkill_cleanup(void)
 166 {
 167         __oaktrail_rfkill_cleanup(wifi_rfkill);
 168         __oaktrail_rfkill_cleanup(bt_rfkill);
 169         __oaktrail_rfkill_cleanup(gps_rfkill);
 170         __oaktrail_rfkill_cleanup(wwan_rfkill);
 171 }
 172
 173 static int oaktrail_rfkill_init(void)
 174 {
 175         int ret;
 176
 177         wifi_rfkill = oaktrail_rfkill_new("oaktrail-wifi",
 178                                           RFKILL_TYPE_WLAN,
 179                                           OT_EC_WIFI_MASK);
 180         if (IS_ERR(wifi_rfkill)) {
 181                 ret = PTR_ERR(wifi_rfkill);
 182                 wifi_rfkill = NULL;
 183                 goto cleanup;
 184         }
 185
 186         bt_rfkill = oaktrail_rfkill_new("oaktrail-bluetooth",
 187                                         RFKILL_TYPE_BLUETOOTH,
 188                                         OT_EC_BT_MASK);
 189         if (IS_ERR(bt_rfkill)) {
 190                 ret = PTR_ERR(bt_rfkill);
 191                 bt_rfkill = NULL;
 192                 goto cleanup;
 193         }
 194
 195         gps_rfkill = oaktrail_rfkill_new("oaktrail-gps",
 196                                          RFKILL_TYPE_GPS,
 197                                          OT_EC_GPS_MASK);
 198         if (IS_ERR(gps_rfkill)) {
 199                 ret = PTR_ERR(gps_rfkill);
 200                 gps_rfkill = NULL;
 201                 goto cleanup;
 202         }
 203
 204         wwan_rfkill = oaktrail_rfkill_new("oaktrail-wwan",
 205                                           RFKILL_TYPE_WWAN,
 206                                           OT_EC_WWAN_MASK);
 207         if (IS_ERR(wwan_rfkill)) {
 208                 ret = PTR_ERR(wwan_rfkill);
 209                 wwan_rfkill = NULL;
 210                 goto cleanup;
 211         }
 212
 213         return 0;
 214
 215 cleanup:
 216         oaktrail_rfkill_cleanup();
 217         return ret;
 218 }
 219
 220
 221 /* backlight */
 222 static int get_backlight_brightness(struct backlight_device *b)
 223 {
 224         u8 value;
 225         ec_read(OT_EC_BL_BRIGHTNESS_ADDRESS, &value);
 226
 227         return value;
 228 }
 229
 230 static int set_backlight_brightness(struct backlight_device *b)
 231 {
 232         u8 percent = (u8) b->props.brightness;
 233         if (percent < 0 || percent > OT_EC_BL_BRIGHTNESS_MAX)
 234                 return -EINVAL;
 235
 236         ec_write(OT_EC_BL_BRIGHTNESS_ADDRESS, percent);
 237         ec_write(OT_EC_BL_CONTROL_ADDRESS, OT_EC_BL_CONTROL_ON_DATA);
 238
 239         return 0;
 240 }
 241
 242 static const struct backlight_ops oaktrail_bl_ops = {
 243         .get_brightness = get_backlight_brightness,
 244         .update_status  = set_backlight_brightness,
 245 };
 246
 247 static int oaktrail_backlight_init(void)
 248 {
 249         struct backlight_device *bd;
 250         struct backlight_properties props;
 251
 252         memset(&props, 0, sizeof(struct backlight_properties));
 253         props.type = BACKLIGHT_PLATFORM;
 254         props.max_brightness = OT_EC_BL_BRIGHTNESS_MAX;
 255         bd = backlight_device_register(DRIVER_NAME,
 256                                        &oaktrail_device->dev, NULL,
 257                                        &oaktrail_bl_ops,
 258                                        &props);
 259
 260         if (IS_ERR(bd)) {
 261                 oaktrail_bl_device = NULL;
 262                 pr_warning("Unable to register backlight device\n");
 263                 return PTR_ERR(bd);
 264         }
 265
 266         oaktrail_bl_device = bd;
 267
 268         bd->props.brightness = get_backlight_brightness(bd);
 269         bd->props.power = FB_BLANK_UNBLANK;
 270         backlight_update_status(bd);
 271
 272         return 0;
 273 }
 274
 275 static void oaktrail_backlight_exit(void)
 276 {
 277         if (oaktrail_bl_device)
 278                 backlight_device_unregister(oaktrail_bl_device);
 279 }
 280
 281 static int oaktrail_probe(struct platform_device *pdev)
 282 {
 283         return 0;
 284 }
 285
 286 static int oaktrail_remove(struct platform_device *pdev)
 287 {
 288         return 0;
 289 }
 290
 291 static struct platform_driver oaktrail_driver = {
 292         .driver = {
 293                 .name = DRIVER_NAME,
 294                 .owner = THIS_MODULE,
 295         },
 296         .probe  = oaktrail_probe,
 297         .remove = oaktrail_remove,
 298 };
 299
 300 static int dmi_check_cb(const struct dmi_system_id *id)
 301 {
 302         pr_info("Identified model '%s'\n", id->ident);
 303         return 0;
 304 }
 305
 306 static struct dmi_system_id __initdata oaktrail_dmi_table[] = {
 307         {
 308                 .ident = "OakTrail platform",
 309                 .matches = {
 310                         DMI_MATCH(DMI_PRODUCT_NAME, "OakTrail platform"),
 311                 },
 312                 .callback = dmi_check_cb
 313         },
 314         { }
 315 };
 316 MODULE_DEVICE_TABLE(dmi, oaktrail_dmi_table);
 317
 318 static int __init oaktrail_init(void)
 319 {
 320         int ret;
 321
 322         if (acpi_disabled) {
 323                 pr_err("ACPI needs to be enabled for this driver to work!\n");
 324                 return -ENODEV;
 325         }
 326
 327         if (!force && !dmi_check_system(oaktrail_dmi_table)) {
 328                 pr_err("Platform not recognized (You could try the module's force-parameter)");
 329                 return -ENODEV;
 330         }
 331
 332         ret = platform_driver_register(&oaktrail_driver);
 333         if (ret) {
 334                 pr_warning("Unable to register platform driver\n");
 335                 goto err_driver_reg;
 336         }
 337
 338         oaktrail_device = platform_device_alloc(DRIVER_NAME, -1);
 339         if (!oaktrail_device) {
 340                 pr_warning("Unable to allocate platform device\n");
 341                 ret = -ENOMEM;
 342                 goto err_device_alloc;
 343         }
 344
 345         ret = platform_device_add(oaktrail_device);
 346         if (ret) {
 347                 pr_warning("Unable to add platform device\n");
 348                 goto err_device_add;
 349         }
 350
 351         if (!acpi_video_backlight_support()) {
 352                 ret = oaktrail_backlight_init();
 353                 if (ret)
 354                         goto err_backlight;
 355
 356         } else
 357                 pr_info("Backlight controlled by ACPI video driver\n");
 358
 359         ret = oaktrail_rfkill_init();
 360         if (ret) {
 361                 pr_warning("Setup rfkill failed\n");
 362                 goto err_rfkill;
 363         }
 364
 365         pr_info("Driver "DRIVER_VERSION" successfully loaded\n");
 366         return 0;
 367
 368 err_rfkill:
 369         oaktrail_backlight_exit();
 370 err_backlight:
 371         platform_device_del(oaktrail_device);
 372 err_device_add:
 373         platform_device_put(oaktrail_device);
 374 err_device_alloc:
 375         platform_driver_unregister(&oaktrail_driver);
 376 err_driver_reg:
 377
 378         return ret;
 379 }
 380
 381 static void __exit oaktrail_cleanup(void)
 382 {
 383         oaktrail_backlight_exit();
 384         oaktrail_rfkill_cleanup();
 385         platform_device_unregister(oaktrail_device);
 386         platform_driver_unregister(&oaktrail_driver);
 387
 388         pr_info("Driver unloaded\n");
 389 }
 390
 391 module_init(oaktrail_init);
 392 module_exit(oaktrail_cleanup);
 393
 394 MODULE_AUTHOR("Yin Kangkai (kangkai.yin@intel.com)");
 395 MODULE_DESCRIPTION("Intel Oaktrail Platform ACPI Extras");
 396 MODULE_VERSION(DRIVER_VERSION);
 397 MODULE_LICENSE("GPL");