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
66struct 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
95static 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
106static 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
115static 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
158static 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
184static 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
217static 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
227static 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
243static 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
257void 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}
268EXPORT_SYMBOL(cma3000_suspend);
269
270
271void 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}
282EXPORT_SYMBOL(cma3000_resume);
283
284struct 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
379err_free_irq:
380 free_irq(irq, data);
381err_free_mem:
382 input_free_device(input_dev);
383 kfree(data);
384err_out:
385 return ERR_PTR(error);
386}
387EXPORT_SYMBOL(cma3000_init);
388
389void 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}
395EXPORT_SYMBOL(cma3000_exit);
396
397MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver");
398MODULE_LICENSE("GPL");
399MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");
400