drivers/input/misc/cma3000_d0x.c

   1 /*
   2  * VTI CMA3000_D0x Accelerometer driver
   3  *
   4  * Copyright (C) 2010 Texas Instruments
   5  * Author: Hemanth V <hemanthv@ti.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/types.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/delay.h>
  23 #include <linux/slab.h>
  24 #include <linux/input.h>
  25 #include <linux/input/cma3000.h>
  26 #include <linux/module.h>
  27
  28 #include "cma3000_d0x.h"
  29
  30 #define CMA3000_WHOAMI      0x00
  31 #define CMA3000_REVID       0x01
  32 #define CMA3000_CTRL        0x02
  33 #define CMA3000_STATUS      0x03
  34 #define CMA3000_RSTR        0x04
  35 #define CMA3000_INTSTATUS   0x05
  36 #define CMA3000_DOUTX       0x06
  37 #define CMA3000_DOUTY       0x07
  38 #define CMA3000_DOUTZ       0x08
  39 #define CMA3000_MDTHR       0x09
  40 #define CMA3000_MDFFTMR     0x0A
  41 #define CMA3000_FFTHR       0x0B
  42
  43 #define CMA3000_RANGE2G    (1 << 7)
  44 #define CMA3000_RANGE8G    (0 << 7)
  45 #define CMA3000_BUSI2C     (0 << 4)
  46 #define CMA3000_MODEMASK   (7 << 1)
  47 #define CMA3000_GRANGEMASK (1 << 7)
  48
  49 #define CMA3000_STATUS_PERR    1
  50 #define CMA3000_INTSTATUS_FFDET (1 << 2)
  51
  52 /* Settling time delay in ms */
  53 #define CMA3000_SETDELAY    30
  54
  55 /* Delay for clearing interrupt in us */
  56 #define CMA3000_INTDELAY    44
  57
  58
  59 /*
  60  * Bit weights in mg for bit 0, other bits need
  61  * multiply factor 2^n. Eight bit is the sign bit.
  62  */
  63 #define BIT_TO_2G  18
  64 #define BIT_TO_8G  71
  65
  66 struct cma3000_accl_data {
  67         const struct cma3000_bus_ops *bus_ops;
  68         const struct cma3000_platform_data *pdata;
  69
  70         struct device *dev;
  71         struct input_dev *input_dev;
  72
  73         int bit_to_mg;
  74         int irq;
  75
  76         int g_range;
  77         u8 mode;
  78
  79         struct mutex mutex;
  80         bool opened;
  81         bool suspended;
  82 };
  83
  84 #define CMA3000_READ(data, reg, msg) \
  85         (data->bus_ops->read(data->dev, reg, msg))
  86 #define CMA3000_SET(data, reg, val, msg) \
  87         ((data)->bus_ops->write(data->dev, reg, val, msg))
  88
  89 /*
  90  * Conversion for each of the eight modes to g, depending
  91  * on G range i.e 2G or 8G. Some modes always operate in
  92  * 8G.
  93  */
  94
  95 static int mode_to_mg[8][2] = {
  96         { 0, 0 },
  97         { BIT_TO_8G, BIT_TO_2G },
  98         { BIT_TO_8G, BIT_TO_2G },
  99         { BIT_TO_8G, BIT_TO_8G },
 100         { BIT_TO_8G, BIT_TO_8G },
 101         { BIT_TO_8G, BIT_TO_2G },
 102         { BIT_TO_8G, BIT_TO_2G },
 103         { 0, 0},
 104 };
 105
 106 static void decode_mg(struct cma3000_accl_data *data, int *datax,
 107                                 int *datay, int *dataz)
 108 {
 109         /* Data in 2's complement, convert to mg */
 110         *datax = ((s8)*datax) * data->bit_to_mg;
 111         *datay = ((s8)*datay) * data->bit_to_mg;
 112         *dataz = ((s8)*dataz) * data->bit_to_mg;
 113 }
 114
 115 static irqreturn_t cma3000_thread_irq(int irq, void *dev_id)
 116 {
 117         struct cma3000_accl_data *data = dev_id;
 118         int datax, datay, dataz, intr_status;
 119         u8 ctrl, mode, range;
 120
 121         intr_status = CMA3000_READ(data, CMA3000_INTSTATUS, "interrupt status");
 122         if (intr_status < 0)
 123                 return IRQ_NONE;
 124
 125         /* Check if free fall is detected, report immediately */
 126         if (intr_status & CMA3000_INTSTATUS_FFDET) {
 127                 input_report_abs(data->input_dev, ABS_MISC, 1);
 128                 input_sync(data->input_dev);
 129         } else {
 130                 input_report_abs(data->input_dev, ABS_MISC, 0);
 131         }
 132
 133         datax = CMA3000_READ(data, CMA3000_DOUTX, "X");
 134         datay = CMA3000_READ(data, CMA3000_DOUTY, "Y");
 135         dataz = CMA3000_READ(data, CMA3000_DOUTZ, "Z");
 136
 137         ctrl = CMA3000_READ(data, CMA3000_CTRL, "ctrl");
 138         mode = (ctrl & CMA3000_MODEMASK) >> 1;
 139         range = (ctrl & CMA3000_GRANGEMASK) >> 7;
 140
 141         data->bit_to_mg = mode_to_mg[mode][range];
 142
 143         /* Interrupt not for this device */
 144         if (data->bit_to_mg == 0)
 145                 return IRQ_NONE;
 146
 147         /* Decode register values to milli g */
 148         decode_mg(data, &datax, &datay, &dataz);
 149
 150         input_report_abs(data->input_dev, ABS_X, datax);
 151         input_report_abs(data->input_dev, ABS_Y, datay);
 152         input_report_abs(data->input_dev, ABS_Z, dataz);
 153         input_sync(data->input_dev);
 154
 155         return IRQ_HANDLED;
 156 }
 157
 158 static int cma3000_reset(struct cma3000_accl_data *data)
 159 {
 160         int val;
 161
 162         /* Reset sequence */
 163         CMA3000_SET(data, CMA3000_RSTR, 0x02, "Reset");
 164         CMA3000_SET(data, CMA3000_RSTR, 0x0A, "Reset");
 165         CMA3000_SET(data, CMA3000_RSTR, 0x04, "Reset");
 166
 167         /* Settling time delay */
 168         mdelay(10);
 169
 170         val = CMA3000_READ(data, CMA3000_STATUS, "Status");
 171         if (val < 0) {
 172                 dev_err(data->dev, "Reset failed\n");
 173                 return val;
 174         }
 175
 176         if (val & CMA3000_STATUS_PERR) {
 177                 dev_err(data->dev, "Parity Error\n");
 178                 return -EIO;
 179         }
 180
 181         return 0;
 182 }
 183
 184 static int cma3000_poweron(struct cma3000_accl_data *data)
 185 {
 186         const struct cma3000_platform_data *pdata = data->pdata;
 187         u8 ctrl = 0;
 188         int ret;
 189
 190         if (data->g_range == CMARANGE_2G) {
 191                 ctrl = (data->mode << 1) | CMA3000_RANGE2G;
 192         } else if (data->g_range == CMARANGE_8G) {
 193                 ctrl = (data->mode << 1) | CMA3000_RANGE8G;
 194         } else {
 195                 dev_info(data->dev,
 196                          "Invalid G range specified, assuming 8G\n");
 197                 ctrl = (data->mode << 1) | CMA3000_RANGE8G;
 198         }
 199
 200         ctrl |= data->bus_ops->ctrl_mod;
 201
 202         CMA3000_SET(data, CMA3000_MDTHR, pdata->mdthr,
 203                     "Motion Detect Threshold");
 204         CMA3000_SET(data, CMA3000_MDFFTMR, pdata->mdfftmr,
 205                     "Time register");
 206         CMA3000_SET(data, CMA3000_FFTHR, pdata->ffthr,
 207                     "Free fall threshold");
 208         ret = CMA3000_SET(data, CMA3000_CTRL, ctrl, "Mode setting");
 209         if (ret < 0)
 210                 return -EIO;
 211
 212         msleep(CMA3000_SETDELAY);
 213
 214         return 0;
 215 }
 216
 217 static int cma3000_poweroff(struct cma3000_accl_data *data)
 218 {
 219         int ret;
 220
 221         ret = CMA3000_SET(data, CMA3000_CTRL, CMAMODE_POFF, "Mode setting");
 222         msleep(CMA3000_SETDELAY);
 223
 224         return ret;
 225 }
 226
 227 static int cma3000_open(struct input_dev *input_dev)
 228 {
 229         struct cma3000_accl_data *data = input_get_drvdata(input_dev);
 230
 231         mutex_lock(&data->mutex);
 232
 233         if (!data->suspended)
 234                 cma3000_poweron(data);
 235
 236         data->opened = true;
 237
 238         mutex_unlock(&data->mutex);
 239
 240         return 0;
 241 }
 242
 243 static void cma3000_close(struct input_dev *input_dev)
 244 {
 245         struct cma3000_accl_data *data = input_get_drvdata(input_dev);
 246
 247         mutex_lock(&data->mutex);
 248
 249         if (!data->suspended)
 250                 cma3000_poweroff(data);
 251
 252         data->opened = false;
 253
 254         mutex_unlock(&data->mutex);
 255 }
 256
 257 void cma3000_suspend(struct cma3000_accl_data *data)
 258 {
 259         mutex_lock(&data->mutex);
 260
 261         if (!data->suspended && data->opened)
 262                 cma3000_poweroff(data);
 263
 264         data->suspended = true;
 265
 266         mutex_unlock(&data->mutex);
 267 }
 268 EXPORT_SYMBOL(cma3000_suspend);
 269
 270
 271 void cma3000_resume(struct cma3000_accl_data *data)
 272 {
 273         mutex_lock(&data->mutex);
 274
 275         if (data->suspended && data->opened)
 276                 cma3000_poweron(data);
 277
 278         data->suspended = false;
 279
 280         mutex_unlock(&data->mutex);
 281 }
 282 EXPORT_SYMBOL(cma3000_resume);
 283
 284 struct cma3000_accl_data *cma3000_init(struct device *dev, int irq,
 285                                        const struct cma3000_bus_ops *bops)
 286 {
 287         const struct cma3000_platform_data *pdata = dev_get_platdata(dev);
 288         struct cma3000_accl_data *data;
 289         struct input_dev *input_dev;
 290         int rev;
 291         int error;
 292
 293         if (!pdata) {
 294                 dev_err(dev, "platform data not found\n");
 295                 error = -EINVAL;
 296                 goto err_out;
 297         }
 298
 299
 300         /* if no IRQ return error */
 301         if (irq == 0) {
 302                 error = -EINVAL;
 303                 goto err_out;
 304         }
 305
 306         data = kzalloc(sizeof(struct cma3000_accl_data), GFP_KERNEL);
 307         input_dev = input_allocate_device();
 308         if (!data || !input_dev) {
 309                 error = -ENOMEM;
 310                 goto err_free_mem;
 311         }
 312
 313         data->dev = dev;
 314         data->input_dev = input_dev;
 315         data->bus_ops = bops;
 316         data->pdata = pdata;
 317         data->irq = irq;
 318         mutex_init(&data->mutex);
 319
 320         data->mode = pdata->mode;
 321         if (data->mode > CMAMODE_POFF) {
 322                 data->mode = CMAMODE_MOTDET;
 323                 dev_warn(dev,
 324                          "Invalid mode specified, assuming Motion Detect\n");
 325         }
 326
 327         data->g_range = pdata->g_range;
 328         if (data->g_range != CMARANGE_2G && data->g_range != CMARANGE_8G) {
 329                 dev_info(dev,
 330                          "Invalid G range specified, assuming 8G\n");
 331                 data->g_range = CMARANGE_8G;
 332         }
 333
 334         input_dev->name = "cma3000-accelerometer";
 335         input_dev->id.bustype = bops->bustype;
 336         input_dev->open = cma3000_open;
 337         input_dev->close = cma3000_close;
 338
 339          __set_bit(EV_ABS, input_dev->evbit);
 340
 341         input_set_abs_params(input_dev, ABS_X,
 342                         -data->g_range, data->g_range, pdata->fuzz_x, 0);
 343         input_set_abs_params(input_dev, ABS_Y,
 344                         -data->g_range, data->g_range, pdata->fuzz_y, 0);
 345         input_set_abs_params(input_dev, ABS_Z,
 346                         -data->g_range, data->g_range, pdata->fuzz_z, 0);
 347         input_set_abs_params(input_dev, ABS_MISC, 0, 1, 0, 0);
 348
 349         input_set_drvdata(input_dev, data);
 350
 351         error = cma3000_reset(data);
 352         if (error)
 353                 goto err_free_mem;
 354
 355         rev = CMA3000_READ(data, CMA3000_REVID, "Revid");
 356         if (rev < 0) {
 357                 error = rev;
 358                 goto err_free_mem;
 359         }
 360
 361         pr_info("CMA3000 Accelerometer: Revision %x\n", rev);
 362
 363         error = request_threaded_irq(irq, NULL, cma3000_thread_irq,
 364                                      pdata->irqflags | IRQF_ONESHOT,
 365                                      "cma3000_d0x", data);
 366         if (error) {
 367                 dev_err(dev, "request_threaded_irq failed\n");
 368                 goto err_free_mem;
 369         }
 370
 371         error = input_register_device(data->input_dev);
 372         if (error) {
 373                 dev_err(dev, "Unable to register input device\n");
 374                 goto err_free_irq;
 375         }
 376
 377         return data;
 378
 379 err_free_irq:
 380         free_irq(irq, data);
 381 err_free_mem:
 382         input_free_device(input_dev);
 383         kfree(data);
 384 err_out:
 385         return ERR_PTR(error);
 386 }
 387 EXPORT_SYMBOL(cma3000_init);
 388
 389 void cma3000_exit(struct cma3000_accl_data *data)
 390 {
 391         free_irq(data->irq, data);
 392         input_unregister_device(data->input_dev);
 393         kfree(data);
 394 }
 395 EXPORT_SYMBOL(cma3000_exit);
 396
 397 MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver");
 398 MODULE_LICENSE("GPL");
 399 MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");