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