drivers/hwmon/lis3lv02d.c

   1 /*
   2  *  lis3lv02d.c - ST LIS3LV02DL accelerometer driver
   3  *
   4  *  Copyright (C) 2007-2008 Yan Burman
   5  *  Copyright (C) 2008 Eric Piel
   6  *  Copyright (C) 2008-2009 Pavel Machek
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/init.h>
  25 #include <linux/dmi.h>
  26 #include <linux/module.h>
  27 #include <linux/types.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/input-polldev.h>
  31 #include <linux/delay.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/freezer.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/miscdevice.h>
  37 #include <asm/atomic.h>
  38 #include "lis3lv02d.h"
  39
  40 #define DRIVER_NAME     "lis3lv02d"
  41
  42 /* joystick device poll interval in milliseconds */
  43 #define MDPS_POLL_INTERVAL 50
  44 /*
  45  * The sensor can also generate interrupts (DRDY) but it's pretty pointless
  46  * because they are generated even if the data do not change. So it's better
  47  * to keep the interrupt for the free-fall event. The values are updated at
  48  * 40Hz (at the lowest frequency), but as it can be pretty time consuming on
  49  * some low processor, we poll the sensor only at 20Hz... enough for the
  50  * joystick.
  51  */
  52
  53 #define LIS3_PWRON_DELAY_WAI_12B        (5000)
  54 #define LIS3_PWRON_DELAY_WAI_8B         (3000)
  55
  56 struct lis3lv02d lis3_dev = {
  57         .misc_wait   = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
  58 };
  59
  60 EXPORT_SYMBOL_GPL(lis3_dev);
  61
  62 static s16 lis3lv02d_read_8(struct lis3lv02d *lis3, int reg)
  63 {
  64         s8 lo;
  65         if (lis3->read(lis3, reg, &lo) < 0)
  66                 return 0;
  67
  68         return lo;
  69 }
  70
  71 static s16 lis3lv02d_read_12(struct lis3lv02d *lis3, int reg)
  72 {
  73         u8 lo, hi;
  74
  75         lis3->read(lis3, reg - 1, &lo);
  76         lis3->read(lis3, reg, &hi);
  77         /* In "12 bit right justified" mode, bit 6, bit 7, bit 8 = bit 5 */
  78         return (s16)((hi << 8) | lo);
  79 }
  80
  81 /**
  82  * lis3lv02d_get_axis - For the given axis, give the value converted
  83  * @axis:      1,2,3 - can also be negative
  84  * @hw_values: raw values returned by the hardware
  85  *
  86  * Returns the converted value.
  87  */
  88 static inline int lis3lv02d_get_axis(s8 axis, int hw_values[3])
  89 {
  90         if (axis > 0)
  91                 return hw_values[axis - 1];
  92         else
  93                 return -hw_values[-axis - 1];
  94 }
  95
  96 /**
  97  * lis3lv02d_get_xyz - Get X, Y and Z axis values from the accelerometer
  98  * @lis3: pointer to the device struct
  99  * @x:    where to store the X axis value
 100  * @y:    where to store the Y axis value
 101  * @z:    where to store the Z axis value
 102  *
 103  * Note that 40Hz input device can eat up about 10% CPU at 800MHZ
 104  */
 105 static void lis3lv02d_get_xyz(struct lis3lv02d *lis3, int *x, int *y, int *z)
 106 {
 107         int position[3];
 108
 109         mutex_lock(&lis3->mutex);
 110         position[0] = lis3->read_data(lis3, OUTX);
 111         position[1] = lis3->read_data(lis3, OUTY);
 112         position[2] = lis3->read_data(lis3, OUTZ);
 113         mutex_unlock(&lis3->mutex);
 114
 115         *x = lis3lv02d_get_axis(lis3->ac.x, position);
 116         *y = lis3lv02d_get_axis(lis3->ac.y, position);
 117         *z = lis3lv02d_get_axis(lis3->ac.z, position);
 118 }
 119
 120 /* conversion btw sampling rate and the register values */
 121 static int lis3_12_rates[4] = {40, 160, 640, 2560};
 122 static int lis3_8_rates[2] = {100, 400};
 123
 124 static int lis3lv02d_get_odr(void)
 125 {
 126         u8 ctrl;
 127         int val;
 128
 129         lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
 130
 131         if (lis3_dev.whoami == WAI_12B)
 132                 val = lis3_12_rates[(ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4];
 133         else
 134                 val = lis3_8_rates[(ctrl & CTRL1_DR) >> 7];
 135         return val;
 136 }
 137
 138 static int lis3lv02d_selftest(struct lis3lv02d *lis3, s16 results[3])
 139 {
 140         u8 reg;
 141         s16 x, y, z;
 142         u8 selftest;
 143         int ret;
 144
 145         mutex_lock(&lis3->mutex);
 146         if (lis3_dev.whoami == WAI_12B)
 147                 selftest = CTRL1_ST;
 148         else
 149                 selftest = CTRL1_STP;
 150
 151         lis3->read(lis3, CTRL_REG1, &reg);
 152         lis3->write(lis3, CTRL_REG1, (reg | selftest));
 153         msleep(lis3->pwron_delay / lis3lv02d_get_odr());
 154
 155         /* Read directly to avoid axis remap */
 156         x = lis3->read_data(lis3, OUTX);
 157         y = lis3->read_data(lis3, OUTY);
 158         z = lis3->read_data(lis3, OUTZ);
 159
 160         /* back to normal settings */
 161         lis3->write(lis3, CTRL_REG1, reg);
 162         msleep(lis3->pwron_delay / lis3lv02d_get_odr());
 163
 164         results[0] = x - lis3->read_data(lis3, OUTX);
 165         results[1] = y - lis3->read_data(lis3, OUTY);
 166         results[2] = z - lis3->read_data(lis3, OUTZ);
 167
 168         ret = 0;
 169         if (lis3->pdata) {
 170                 int i;
 171                 for (i = 0; i < 3; i++) {
 172                         /* Check against selftest acceptance limits */
 173                         if ((results[i] < lis3->pdata->st_min_limits[i]) ||
 174                             (results[i] > lis3->pdata->st_max_limits[i])) {
 175                                 ret = -EIO;
 176                                 goto fail;
 177                         }
 178                 }
 179         }
 180
 181         /* test passed */
 182 fail:
 183         mutex_unlock(&lis3->mutex);
 184         return ret;
 185 }
 186
 187 void lis3lv02d_poweroff(struct lis3lv02d *lis3)
 188 {
 189         /* disable X,Y,Z axis and power down */
 190         lis3->write(lis3, CTRL_REG1, 0x00);
 191 }
 192 EXPORT_SYMBOL_GPL(lis3lv02d_poweroff);
 193
 194 void lis3lv02d_poweron(struct lis3lv02d *lis3)
 195 {
 196         u8 reg;
 197
 198         lis3->init(lis3);
 199
 200         /* LIS3 power on delay is quite long */
 201         msleep(lis3->pwron_delay / lis3lv02d_get_odr());
 202
 203         /*
 204          * Common configuration
 205          * BDU: (12 bits sensors only) LSB and MSB values are not updated until
 206          *      both have been read. So the value read will always be correct.
 207          */
 208         if (lis3->whoami ==  WAI_12B) {
 209                 lis3->read(lis3, CTRL_REG2, &reg);
 210                 reg |= CTRL2_BDU;
 211                 lis3->write(lis3, CTRL_REG2, reg);
 212         }
 213 }
 214 EXPORT_SYMBOL_GPL(lis3lv02d_poweron);
 215
 216
 217 static irqreturn_t lis302dl_interrupt(int irq, void *dummy)
 218 {
 219         /*
 220          * Be careful: on some HP laptops the bios force DD when on battery and
 221          * the lid is closed. This leads to interrupts as soon as a little move
 222          * is done.
 223          */
 224         atomic_inc(&lis3_dev.count);
 225
 226         wake_up_interruptible(&lis3_dev.misc_wait);
 227         kill_fasync(&lis3_dev.async_queue, SIGIO, POLL_IN);
 228         return IRQ_HANDLED;
 229 }
 230
 231 static int lis3lv02d_misc_open(struct inode *inode, struct file *file)
 232 {
 233         int ret;
 234
 235         if (test_and_set_bit(0, &lis3_dev.misc_opened))
 236                 return -EBUSY; /* already open */
 237
 238         atomic_set(&lis3_dev.count, 0);
 239
 240         /*
 241          * The sensor can generate interrupts for free-fall and direction
 242          * detection (distinguishable with FF_WU_SRC and DD_SRC) but to keep
 243          * the things simple and _fast_ we activate it only for free-fall, so
 244          * no need to read register (very slow with ACPI). For the same reason,
 245          * we forbid shared interrupts.
 246          *
 247          * IRQF_TRIGGER_RISING seems pointless on HP laptops because the
 248          * io-apic is not configurable (and generates a warning) but I keep it
 249          * in case of support for other hardware.
 250          */
 251         ret = request_irq(lis3_dev.irq, lis302dl_interrupt, IRQF_TRIGGER_RISING,
 252                           DRIVER_NAME, &lis3_dev);
 253
 254         if (ret) {
 255                 clear_bit(0, &lis3_dev.misc_opened);
 256                 printk(KERN_ERR DRIVER_NAME ": IRQ%d allocation failed\n", lis3_dev.irq);
 257                 return -EBUSY;
 258         }
 259         return 0;
 260 }
 261
 262 static int lis3lv02d_misc_release(struct inode *inode, struct file *file)
 263 {
 264         fasync_helper(-1, file, 0, &lis3_dev.async_queue);
 265         free_irq(lis3_dev.irq, &lis3_dev);
 266         clear_bit(0, &lis3_dev.misc_opened); /* release the device */
 267         return 0;
 268 }
 269
 270 static ssize_t lis3lv02d_misc_read(struct file *file, char __user *buf,
 271                                 size_t count, loff_t *pos)
 272 {
 273         DECLARE_WAITQUEUE(wait, current);
 274         u32 data;
 275         unsigned char byte_data;
 276         ssize_t retval = 1;
 277
 278         if (count < 1)
 279                 return -EINVAL;
 280
 281         add_wait_queue(&lis3_dev.misc_wait, &wait);
 282         while (true) {
 283                 set_current_state(TASK_INTERRUPTIBLE);
 284                 data = atomic_xchg(&lis3_dev.count, 0);
 285                 if (data)
 286                         break;
 287
 288                 if (file->f_flags & O_NONBLOCK) {
 289                         retval = -EAGAIN;
 290                         goto out;
 291                 }
 292
 293                 if (signal_pending(current)) {
 294                         retval = -ERESTARTSYS;
 295                         goto out;
 296                 }
 297
 298                 schedule();
 299         }
 300
 301         if (data < 255)
 302                 byte_data = data;
 303         else
 304                 byte_data = 255;
 305
 306         /* make sure we are not going into copy_to_user() with
 307          * TASK_INTERRUPTIBLE state */
 308         set_current_state(TASK_RUNNING);
 309         if (copy_to_user(buf, &byte_data, sizeof(byte_data)))
 310                 retval = -EFAULT;
 311
 312 out:
 313         __set_current_state(TASK_RUNNING);
 314         remove_wait_queue(&lis3_dev.misc_wait, &wait);
 315
 316         return retval;
 317 }
 318
 319 static unsigned int lis3lv02d_misc_poll(struct file *file, poll_table *wait)
 320 {
 321         poll_wait(file, &lis3_dev.misc_wait, wait);
 322         if (atomic_read(&lis3_dev.count))
 323                 return POLLIN | POLLRDNORM;
 324         return 0;
 325 }
 326
 327 static int lis3lv02d_misc_fasync(int fd, struct file *file, int on)
 328 {
 329         return fasync_helper(fd, file, on, &lis3_dev.async_queue);
 330 }
 331
 332 static const struct file_operations lis3lv02d_misc_fops = {
 333         .owner   = THIS_MODULE,
 334         .llseek  = no_llseek,
 335         .read    = lis3lv02d_misc_read,
 336         .open    = lis3lv02d_misc_open,
 337         .release = lis3lv02d_misc_release,
 338         .poll    = lis3lv02d_misc_poll,
 339         .fasync  = lis3lv02d_misc_fasync,
 340 };
 341
 342 static struct miscdevice lis3lv02d_misc_device = {
 343         .minor   = MISC_DYNAMIC_MINOR,
 344         .name    = "freefall",
 345         .fops    = &lis3lv02d_misc_fops,
 346 };
 347
 348 static void lis3lv02d_joystick_poll(struct input_polled_dev *pidev)
 349 {
 350         int x, y, z;
 351
 352         lis3lv02d_get_xyz(&lis3_dev, &x, &y, &z);
 353         input_report_abs(pidev->input, ABS_X, x - lis3_dev.xcalib);
 354         input_report_abs(pidev->input, ABS_Y, y - lis3_dev.ycalib);
 355         input_report_abs(pidev->input, ABS_Z, z - lis3_dev.zcalib);
 356         input_sync(pidev->input);
 357 }
 358
 359
 360 static inline void lis3lv02d_calibrate_joystick(void)
 361 {
 362         lis3lv02d_get_xyz(&lis3_dev,
 363                 &lis3_dev.xcalib, &lis3_dev.ycalib, &lis3_dev.zcalib);
 364 }
 365
 366 int lis3lv02d_joystick_enable(void)
 367 {
 368         struct input_dev *input_dev;
 369         int err;
 370
 371         if (lis3_dev.idev)
 372                 return -EINVAL;
 373
 374         lis3_dev.idev = input_allocate_polled_device();
 375         if (!lis3_dev.idev)
 376                 return -ENOMEM;
 377
 378         lis3_dev.idev->poll = lis3lv02d_joystick_poll;
 379         lis3_dev.idev->poll_interval = MDPS_POLL_INTERVAL;
 380         input_dev = lis3_dev.idev->input;
 381
 382         lis3lv02d_calibrate_joystick();
 383
 384         input_dev->name       = "ST LIS3LV02DL Accelerometer";
 385         input_dev->phys       = DRIVER_NAME "/input0";
 386         input_dev->id.bustype = BUS_HOST;
 387         input_dev->id.vendor  = 0;
 388         input_dev->dev.parent = &lis3_dev.pdev->dev;
 389
 390         set_bit(EV_ABS, input_dev->evbit);
 391         input_set_abs_params(input_dev, ABS_X, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
 392         input_set_abs_params(input_dev, ABS_Y, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
 393         input_set_abs_params(input_dev, ABS_Z, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
 394
 395         err = input_register_polled_device(lis3_dev.idev);
 396         if (err) {
 397                 input_free_polled_device(lis3_dev.idev);
 398                 lis3_dev.idev = NULL;
 399         }
 400
 401         return err;
 402 }
 403 EXPORT_SYMBOL_GPL(lis3lv02d_joystick_enable);
 404
 405 void lis3lv02d_joystick_disable(void)
 406 {
 407         if (!lis3_dev.idev)
 408                 return;
 409
 410         if (lis3_dev.irq)
 411                 misc_deregister(&lis3lv02d_misc_device);
 412         input_unregister_polled_device(lis3_dev.idev);
 413         input_free_polled_device(lis3_dev.idev);
 414         lis3_dev.idev = NULL;
 415 }
 416 EXPORT_SYMBOL_GPL(lis3lv02d_joystick_disable);
 417
 418 /* Sysfs stuff */
 419 static ssize_t lis3lv02d_selftest_show(struct device *dev,
 420                                 struct device_attribute *attr, char *buf)
 421 {
 422         int result;
 423         s16 values[3];
 424
 425         result = lis3lv02d_selftest(&lis3_dev, values);
 426         return sprintf(buf, "%s %d %d %d\n", result == 0 ? "OK" : "FAIL",
 427                 values[0], values[1], values[2]);
 428 }
 429
 430 static ssize_t lis3lv02d_position_show(struct device *dev,
 431                                 struct device_attribute *attr, char *buf)
 432 {
 433         int x, y, z;
 434
 435         lis3lv02d_get_xyz(&lis3_dev, &x, &y, &z);
 436         return sprintf(buf, "(%d,%d,%d)\n", x, y, z);
 437 }
 438
 439 static ssize_t lis3lv02d_calibrate_show(struct device *dev,
 440                                 struct device_attribute *attr, char *buf)
 441 {
 442         return sprintf(buf, "(%d,%d,%d)\n", lis3_dev.xcalib, lis3_dev.ycalib, lis3_dev.zcalib);
 443 }
 444
 445 static ssize_t lis3lv02d_calibrate_store(struct device *dev,
 446                                 struct device_attribute *attr,
 447                                 const char *buf, size_t count)
 448 {
 449         lis3lv02d_calibrate_joystick();
 450         return count;
 451 }
 452
 453 static ssize_t lis3lv02d_rate_show(struct device *dev,
 454                         struct device_attribute *attr, char *buf)
 455 {
 456         return sprintf(buf, "%d\n", lis3lv02d_get_odr());
 457 }
 458
 459 static DEVICE_ATTR(selftest, S_IRUSR, lis3lv02d_selftest_show, NULL);
 460 static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL);
 461 static DEVICE_ATTR(calibrate, S_IRUGO|S_IWUSR, lis3lv02d_calibrate_show,
 462         lis3lv02d_calibrate_store);
 463 static DEVICE_ATTR(rate, S_IRUGO, lis3lv02d_rate_show, NULL);
 464
 465 static struct attribute *lis3lv02d_attributes[] = {
 466         &dev_attr_selftest.attr,
 467         &dev_attr_position.attr,
 468         &dev_attr_calibrate.attr,
 469         &dev_attr_rate.attr,
 470         NULL
 471 };
 472
 473 static struct attribute_group lis3lv02d_attribute_group = {
 474         .attrs = lis3lv02d_attributes
 475 };
 476
 477
 478 static int lis3lv02d_add_fs(struct lis3lv02d *lis3)
 479 {
 480         lis3->pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
 481         if (IS_ERR(lis3->pdev))
 482                 return PTR_ERR(lis3->pdev);
 483
 484         return sysfs_create_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
 485 }
 486
 487 int lis3lv02d_remove_fs(struct lis3lv02d *lis3)
 488 {
 489         sysfs_remove_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
 490         platform_device_unregister(lis3->pdev);
 491         return 0;
 492 }
 493 EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs);
 494
 495 /*
 496  * Initialise the accelerometer and the various subsystems.
 497  * Should be rather independent of the bus system.
 498  */
 499 int lis3lv02d_init_device(struct lis3lv02d *dev)
 500 {
 501         dev->whoami = lis3lv02d_read_8(dev, WHO_AM_I);
 502
 503         switch (dev->whoami) {
 504         case WAI_12B:
 505                 printk(KERN_INFO DRIVER_NAME ": 12 bits sensor found\n");
 506                 dev->read_data = lis3lv02d_read_12;
 507                 dev->mdps_max_val = 2048;
 508                 dev->pwron_delay = LIS3_PWRON_DELAY_WAI_12B;
 509                 break;
 510         case WAI_8B:
 511                 printk(KERN_INFO DRIVER_NAME ": 8 bits sensor found\n");
 512                 dev->read_data = lis3lv02d_read_8;
 513                 dev->mdps_max_val = 128;
 514                 dev->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
 515                 break;
 516         default:
 517                 printk(KERN_ERR DRIVER_NAME
 518                         ": unknown sensor type 0x%X\n", dev->whoami);
 519                 return -EINVAL;
 520         }
 521
 522         mutex_init(&dev->mutex);
 523
 524         lis3lv02d_add_fs(dev);
 525         lis3lv02d_poweron(dev);
 526
 527         if (lis3lv02d_joystick_enable())
 528                 printk(KERN_ERR DRIVER_NAME ": joystick initialization failed\n");
 529
 530         /* passing in platform specific data is purely optional and only
 531          * used by the SPI transport layer at the moment */
 532         if (dev->pdata) {
 533                 struct lis3lv02d_platform_data *p = dev->pdata;
 534
 535                 if (p->click_flags && (dev->whoami == WAI_8B)) {
 536                         dev->write(dev, CLICK_CFG, p->click_flags);
 537                         dev->write(dev, CLICK_TIMELIMIT, p->click_time_limit);
 538                         dev->write(dev, CLICK_LATENCY, p->click_latency);
 539                         dev->write(dev, CLICK_WINDOW, p->click_window);
 540                         dev->write(dev, CLICK_THSZ, p->click_thresh_z & 0xf);
 541                         dev->write(dev, CLICK_THSY_X,
 542                                         (p->click_thresh_x & 0xf) |
 543                                         (p->click_thresh_y << 4));
 544                 }
 545
 546                 if (p->wakeup_flags && (dev->whoami == WAI_8B)) {
 547                         dev->write(dev, FF_WU_CFG_1, p->wakeup_flags);
 548                         dev->write(dev, FF_WU_THS_1, p->wakeup_thresh & 0x7f);
 549                         /* default to 2.5ms for now */
 550                         dev->write(dev, FF_WU_DURATION_1, 1);
 551                         /* enable high pass filter for both free-fall units */
 552                         dev->write(dev, CTRL_REG2, HP_FF_WU1 | HP_FF_WU2);
 553                 }
 554
 555                 if (p->irq_cfg)
 556                         dev->write(dev, CTRL_REG3, p->irq_cfg);
 557         }
 558
 559         /* bail if we did not get an IRQ from the bus layer */
 560         if (!dev->irq) {
 561                 printk(KERN_ERR DRIVER_NAME
 562                         ": No IRQ. Disabling /dev/freefall\n");
 563                 goto out;
 564         }
 565
 566         if (misc_register(&lis3lv02d_misc_device))
 567                 printk(KERN_ERR DRIVER_NAME ": misc_register failed\n");
 568 out:
 569         return 0;
 570 }
 571 EXPORT_SYMBOL_GPL(lis3lv02d_init_device);
 572
 573 MODULE_DESCRIPTION("ST LIS3LV02Dx three-axis digital accelerometer driver");
 574 MODULE_AUTHOR("Yan Burman, Eric Piel, Pavel Machek");
 575 MODULE_LICENSE("GPL");