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>"); 400