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 27 #include "cma3000_d0x.h" 28 29 #define CMA3000_WHOAMI 0x00 30 #define CMA3000_REVID 0x01 31 #define CMA3000_CTRL 0x02 32 #define CMA3000_STATUS 0x03 33 #define CMA3000_RSTR 0x04 34 #define CMA3000_INTSTATUS 0x05 35 #define CMA3000_DOUTX 0x06 36 #define CMA3000_DOUTY 0x07 37 #define CMA3000_DOUTZ 0x08 38 #define CMA3000_MDTHR 0x09 39 #define CMA3000_MDFFTMR 0x0A 40 #define CMA3000_FFTHR 0x0B 41 42 #define CMA3000_RANGE2G (1 << 7) 43 #define CMA3000_RANGE8G (0 << 7) 44 #define CMA3000_BUSI2C (0 << 4) 45 #define CMA3000_MODEMASK (7 << 1) 46 #define CMA3000_GRANGEMASK (1 << 7) 47 48 #define CMA3000_STATUS_PERR 1 49 #define CMA3000_INTSTATUS_FFDET (1 << 2) 50 51 /* Settling time delay in ms */ 52 #define CMA3000_SETDELAY 30 53 54 /* Delay for clearing interrupt in us */ 55 #define CMA3000_INTDELAY 44 56 57 58 /* 59 * Bit weights in mg for bit 0, other bits need 60 * multipy factor 2^n. Eight bit is the sign bit. 61 */ 62 #define BIT_TO_2G 18 63 #define BIT_TO_8G 71 64 65 struct cma3000_accl_data { 66 const struct cma3000_bus_ops *bus_ops; 67 const struct cma3000_platform_data *pdata; 68 69 struct device *dev; 70 struct input_dev *input_dev; 71 72 int bit_to_mg; 73 int irq; 74 75 int g_range; 76 u8 mode; 77 78 struct mutex mutex; 79 bool opened; 80 bool suspended; 81 }; 82 83 #define CMA3000_READ(data, reg, msg) \ 84 (data->bus_ops->read(data->dev, reg, msg)) 85 #define CMA3000_SET(data, reg, val, msg) \ 86 ((data)->bus_ops->write(data->dev, reg, val, msg)) 87 88 /* 89 * Conversion for each of the eight modes to g, depending 90 * on G range i.e 2G or 8G. Some modes always operate in 91 * 8G. 92 */ 93 94 static int mode_to_mg[8][2] = { 95 { 0, 0 }, 96 { BIT_TO_8G, BIT_TO_2G }, 97 { BIT_TO_8G, BIT_TO_2G }, 98 { BIT_TO_8G, BIT_TO_8G }, 99 { BIT_TO_8G, BIT_TO_8G }, 100 { BIT_TO_8G, BIT_TO_2G }, 101 { BIT_TO_8G, BIT_TO_2G }, 102 { 0, 0}, 103 }; 104 105 static void decode_mg(struct cma3000_accl_data *data, int *datax, 106 int *datay, int *dataz) 107 { 108 /* Data in 2's complement, convert to mg */ 109 *datax = ((s8)*datax) * data->bit_to_mg; 110 *datay = ((s8)*datay) * data->bit_to_mg; 111 *dataz = ((s8)*dataz) * data->bit_to_mg; 112 } 113 114 static irqreturn_t cma3000_thread_irq(int irq, void *dev_id) 115 { 116 struct cma3000_accl_data *data = dev_id; 117 int datax, datay, dataz; 118 u8 ctrl, mode, range, intr_status; 119 120 intr_status = CMA3000_READ(data, CMA3000_INTSTATUS, "interrupt status"); 121 if (intr_status < 0) 122 return IRQ_NONE; 123 124 /* Check if free fall is detected, report immediately */ 125 if (intr_status & CMA3000_INTSTATUS_FFDET) { 126 input_report_abs(data->input_dev, ABS_MISC, 1); 127 input_sync(data->input_dev); 128 } else { 129 input_report_abs(data->input_dev, ABS_MISC, 0); 130 } 131 132 datax = CMA3000_READ(data, CMA3000_DOUTX, "X"); 133 datay = CMA3000_READ(data, CMA3000_DOUTY, "Y"); 134 dataz = CMA3000_READ(data, CMA3000_DOUTZ, "Z"); 135 136 ctrl = CMA3000_READ(data, CMA3000_CTRL, "ctrl"); 137 mode = (ctrl & CMA3000_MODEMASK) >> 1; 138 range = (ctrl & CMA3000_GRANGEMASK) >> 7; 139 140 data->bit_to_mg = mode_to_mg[mode][range]; 141 142 /* Interrupt not for this device */ 143 if (data->bit_to_mg == 0) 144 return IRQ_NONE; 145 146 /* Decode register values to milli g */ 147 decode_mg(data, &datax, &datay, &dataz); 148 149 input_report_abs(data->input_dev, ABS_X, datax); 150 input_report_abs(data->input_dev, ABS_Y, datay); 151 input_report_abs(data->input_dev, ABS_Z, dataz); 152 input_sync(data->input_dev); 153 154 return IRQ_HANDLED; 155 } 156 157 static int cma3000_reset(struct cma3000_accl_data *data) 158 { 159 int val; 160 161 /* Reset sequence */ 162 CMA3000_SET(data, CMA3000_RSTR, 0x02, "Reset"); 163 CMA3000_SET(data, CMA3000_RSTR, 0x0A, "Reset"); 164 CMA3000_SET(data, CMA3000_RSTR, 0x04, "Reset"); 165 166 /* Settling time delay */ 167 mdelay(10); 168 169 val = CMA3000_READ(data, CMA3000_STATUS, "Status"); 170 if (val < 0) { 171 dev_err(data->dev, "Reset failed\n"); 172 return val; 173 } 174 175 if (val & CMA3000_STATUS_PERR) { 176 dev_err(data->dev, "Parity Error\n"); 177 return -EIO; 178 } 179 180 return 0; 181 } 182 183 static int cma3000_poweron(struct cma3000_accl_data *data) 184 { 185 const struct cma3000_platform_data *pdata = data->pdata; 186 u8 ctrl = 0; 187 int ret; 188 189 if (data->g_range == CMARANGE_2G) { 190 ctrl = (data->mode << 1) | CMA3000_RANGE2G; 191 } else if (data->g_range == CMARANGE_8G) { 192 ctrl = (data->mode << 1) | CMA3000_RANGE8G; 193 } else { 194 dev_info(data->dev, 195 "Invalid G range specified, assuming 8G\n"); 196 ctrl = (data->mode << 1) | CMA3000_RANGE8G; 197 } 198 199 ctrl |= data->bus_ops->ctrl_mod; 200 201 CMA3000_SET(data, CMA3000_MDTHR, pdata->mdthr, 202 "Motion Detect Threshold"); 203 CMA3000_SET(data, CMA3000_MDFFTMR, pdata->mdfftmr, 204 "Time register"); 205 CMA3000_SET(data, CMA3000_FFTHR, pdata->ffthr, 206 "Free fall threshold"); 207 ret = CMA3000_SET(data, CMA3000_CTRL, ctrl, "Mode setting"); 208 if (ret < 0) 209 return -EIO; 210 211 msleep(CMA3000_SETDELAY); 212 213 return 0; 214 } 215 216 static int cma3000_poweroff(struct cma3000_accl_data *data) 217 { 218 int ret; 219 220 ret = CMA3000_SET(data, CMA3000_CTRL, CMAMODE_POFF, "Mode setting"); 221 msleep(CMA3000_SETDELAY); 222 223 return ret; 224 } 225 226 static int cma3000_open(struct input_dev *input_dev) 227 { 228 struct cma3000_accl_data *data = input_get_drvdata(input_dev); 229 230 mutex_lock(&data->mutex); 231 232 if (!data->suspended) 233 cma3000_poweron(data); 234 235 data->opened = true; 236 237 mutex_unlock(&data->mutex); 238 239 return 0; 240 } 241 242 static void cma3000_close(struct input_dev *input_dev) 243 { 244 struct cma3000_accl_data *data = input_get_drvdata(input_dev); 245 246 mutex_lock(&data->mutex); 247 248 if (!data->suspended) 249 cma3000_poweroff(data); 250 251 data->opened = false; 252 253 mutex_unlock(&data->mutex); 254 } 255 256 void cma3000_suspend(struct cma3000_accl_data *data) 257 { 258 mutex_lock(&data->mutex); 259 260 if (!data->suspended && data->opened) 261 cma3000_poweroff(data); 262 263 data->suspended = true; 264 265 mutex_unlock(&data->mutex); 266 } 267 EXPORT_SYMBOL(cma3000_suspend); 268 269 270 void cma3000_resume(struct cma3000_accl_data *data) 271 { 272 mutex_lock(&data->mutex); 273 274 if (data->suspended && data->opened) 275 cma3000_poweron(data); 276 277 data->suspended = false; 278 279 mutex_unlock(&data->mutex); 280 } 281 EXPORT_SYMBOL(cma3000_resume); 282 283 struct cma3000_accl_data *cma3000_init(struct device *dev, int irq, 284 const struct cma3000_bus_ops *bops) 285 { 286 const struct cma3000_platform_data *pdata = dev->platform_data; 287 struct cma3000_accl_data *data; 288 struct input_dev *input_dev; 289 int rev; 290 int error; 291 292 if (!pdata) { 293 dev_err(dev, "platform data not found\n"); 294 error = -EINVAL; 295 goto err_out; 296 } 297 298 299 /* if no IRQ return error */ 300 if (irq == 0) { 301 error = -EINVAL; 302 goto err_out; 303 } 304 305 data = kzalloc(sizeof(struct cma3000_accl_data), GFP_KERNEL); 306 input_dev = input_allocate_device(); 307 if (!data || !input_dev) { 308 error = -ENOMEM; 309 goto err_free_mem; 310 } 311 312 data->dev = dev; 313 data->input_dev = input_dev; 314 data->bus_ops = bops; 315 data->pdata = pdata; 316 data->irq = irq; 317 mutex_init(&data->mutex); 318 319 data->mode = pdata->mode; 320 if (data->mode < CMAMODE_DEFAULT || data->mode > CMAMODE_POFF) { 321 data->mode = CMAMODE_MOTDET; 322 dev_warn(dev, 323 "Invalid mode specified, assuming Motion Detect\n"); 324 } 325 326 data->g_range = pdata->g_range; 327 if (data->g_range != CMARANGE_2G && data->g_range != CMARANGE_8G) { 328 dev_info(dev, 329 "Invalid G range specified, assuming 8G\n"); 330 data->g_range = CMARANGE_8G; 331 } 332 333 input_dev->name = "cma3000-accelerometer"; 334 input_dev->id.bustype = bops->bustype; 335 input_dev->open = cma3000_open; 336 input_dev->close = cma3000_close; 337 338 __set_bit(EV_ABS, input_dev->evbit); 339 340 input_set_abs_params(input_dev, ABS_X, 341 -data->g_range, data->g_range, pdata->fuzz_x, 0); 342 input_set_abs_params(input_dev, ABS_Y, 343 -data->g_range, data->g_range, pdata->fuzz_y, 0); 344 input_set_abs_params(input_dev, ABS_Z, 345 -data->g_range, data->g_range, pdata->fuzz_z, 0); 346 input_set_abs_params(input_dev, ABS_MISC, 0, 1, 0, 0); 347 348 input_set_drvdata(input_dev, data); 349 350 error = cma3000_reset(data); 351 if (error) 352 goto err_free_mem; 353 354 rev = CMA3000_READ(data, CMA3000_REVID, "Revid"); 355 if (rev < 0) { 356 error = rev; 357 goto err_free_mem; 358 } 359 360 pr_info("CMA3000 Accelerometer: Revision %x\n", rev); 361 362 error = request_threaded_irq(irq, NULL, cma3000_thread_irq, 363 pdata->irqflags | IRQF_ONESHOT, 364 "cma3000_d0x", data); 365 if (error) { 366 dev_err(dev, "request_threaded_irq failed\n"); 367 goto err_free_mem; 368 } 369 370 error = input_register_device(data->input_dev); 371 if (error) { 372 dev_err(dev, "Unable to register input device\n"); 373 goto err_free_irq; 374 } 375 376 return data; 377 378 err_free_irq: 379 free_irq(irq, data); 380 err_free_mem: 381 input_free_device(input_dev); 382 kfree(data); 383 err_out: 384 return ERR_PTR(error); 385 } 386 EXPORT_SYMBOL(cma3000_init); 387 388 void cma3000_exit(struct cma3000_accl_data *data) 389 { 390 free_irq(data->irq, data); 391 input_unregister_device(data->input_dev); 392 kfree(data); 393 } 394 EXPORT_SYMBOL(cma3000_exit); 395 396 MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver"); 397 MODULE_LICENSE("GPL"); 398 MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>"); 399