cma3000_d0x.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * VTI CMA3000_D0x Accelerometer driver
  4 *
  5 * Copyright (C) 2010 Texas Instruments
  6 * Author: Hemanth V <hemanthv@ti.com>
  7 */
  8
  9#include <linux/export.h>
 10#include <linux/types.h>
 11#include <linux/interrupt.h>
 12#include <linux/delay.h>
 13#include <linux/slab.h>
 14#include <linux/input.h>
 15#include <linux/input/cma3000.h>
 16#include <linux/module.h>
 17
 18#include "cma3000_d0x.h"
 19
 20#define CMA3000_WHOAMI      0x00
 21#define CMA3000_REVID       0x01
 22#define CMA3000_CTRL        0x02
 23#define CMA3000_STATUS      0x03
 24#define CMA3000_RSTR        0x04
 25#define CMA3000_INTSTATUS   0x05
 26#define CMA3000_DOUTX       0x06
 27#define CMA3000_DOUTY       0x07
 28#define CMA3000_DOUTZ       0x08
 29#define CMA3000_MDTHR       0x09
 30#define CMA3000_MDFFTMR     0x0A
 31#define CMA3000_FFTHR       0x0B
 32
 33#define CMA3000_RANGE2G    (1 << 7)
 34#define CMA3000_RANGE8G    (0 << 7)
 35#define CMA3000_BUSI2C     (0 << 4)
 36#define CMA3000_MODEMASK   (7 << 1)
 37#define CMA3000_GRANGEMASK (1 << 7)
 38
 39#define CMA3000_STATUS_PERR    1
 40#define CMA3000_INTSTATUS_FFDET (1 << 2)
 41
 42/* Settling time delay in ms */
 43#define CMA3000_SETDELAY    30
 44
 45/* Delay for clearing interrupt in us */
 46#define CMA3000_INTDELAY    44
 47
 48
 49/*
 50 * Bit weights in mg for bit 0, other bits need
 51 * multiply factor 2^n. Eight bit is the sign bit.
 52 */
 53#define BIT_TO_2G  18
 54#define BIT_TO_8G  71
 55
 56struct cma3000_accl_data {
 57	const struct cma3000_bus_ops *bus_ops;
 58	const struct cma3000_platform_data *pdata;
 59
 60	struct device *dev;
 61	struct input_dev *input_dev;
 62
 63	int bit_to_mg;
 64	int irq;
 65
 66	int g_range;
 67	u8 mode;
 68
 69	struct mutex mutex;
 70	bool opened;
 71	bool suspended;
 72};
 73
 74#define CMA3000_READ(data, reg, msg) \
 75	(data->bus_ops->read(data->dev, reg, msg))
 76#define CMA3000_SET(data, reg, val, msg) \
 77	((data)->bus_ops->write(data->dev, reg, val, msg))
 78
 79/*
 80 * Conversion for each of the eight modes to g, depending
 81 * on G range i.e 2G or 8G. Some modes always operate in
 82 * 8G.
 83 */
 84
 85static int mode_to_mg[8][2] = {
 86	{ 0, 0 },
 87	{ BIT_TO_8G, BIT_TO_2G },
 88	{ BIT_TO_8G, BIT_TO_2G },
 89	{ BIT_TO_8G, BIT_TO_8G },
 90	{ BIT_TO_8G, BIT_TO_8G },
 91	{ BIT_TO_8G, BIT_TO_2G },
 92	{ BIT_TO_8G, BIT_TO_2G },
 93	{ 0, 0},
 94};
 95
 96static void decode_mg(struct cma3000_accl_data *data, int *datax,
 97				int *datay, int *dataz)
 98{
 99	/* Data in 2's complement, convert to mg */
100	*datax = ((s8)*datax) * data->bit_to_mg;
101	*datay = ((s8)*datay) * data->bit_to_mg;
102	*dataz = ((s8)*dataz) * data->bit_to_mg;
103}
104
105static irqreturn_t cma3000_thread_irq(int irq, void *dev_id)
106{
107	struct cma3000_accl_data *data = dev_id;
108	int datax, datay, dataz, intr_status;
109	u8 ctrl, mode, range;
110
111	intr_status = CMA3000_READ(data, CMA3000_INTSTATUS, "interrupt status");
112	if (intr_status < 0)
113		return IRQ_NONE;
114
115	/* Check if free fall is detected, report immediately */
116	if (intr_status & CMA3000_INTSTATUS_FFDET) {
117		input_report_abs(data->input_dev, ABS_MISC, 1);
118		input_sync(data->input_dev);
119	} else {
120		input_report_abs(data->input_dev, ABS_MISC, 0);
121	}
122
123	datax = CMA3000_READ(data, CMA3000_DOUTX, "X");
124	datay = CMA3000_READ(data, CMA3000_DOUTY, "Y");
125	dataz = CMA3000_READ(data, CMA3000_DOUTZ, "Z");
126
127	ctrl = CMA3000_READ(data, CMA3000_CTRL, "ctrl");
128	mode = (ctrl & CMA3000_MODEMASK) >> 1;
129	range = (ctrl & CMA3000_GRANGEMASK) >> 7;
130
131	data->bit_to_mg = mode_to_mg[mode][range];
132
133	/* Interrupt not for this device */
134	if (data->bit_to_mg == 0)
135		return IRQ_NONE;
136
137	/* Decode register values to milli g */
138	decode_mg(data, &datax, &datay, &dataz);
139
140	input_report_abs(data->input_dev, ABS_X, datax);
141	input_report_abs(data->input_dev, ABS_Y, datay);
142	input_report_abs(data->input_dev, ABS_Z, dataz);
143	input_sync(data->input_dev);
144
145	return IRQ_HANDLED;
146}
147
148static int cma3000_reset(struct cma3000_accl_data *data)
149{
150	int val;
151
152	/* Reset sequence */
153	CMA3000_SET(data, CMA3000_RSTR, 0x02, "Reset");
154	CMA3000_SET(data, CMA3000_RSTR, 0x0A, "Reset");
155	CMA3000_SET(data, CMA3000_RSTR, 0x04, "Reset");
156
157	/* Settling time delay */
158	mdelay(10);
159
160	val = CMA3000_READ(data, CMA3000_STATUS, "Status");
161	if (val < 0) {
162		dev_err(data->dev, "Reset failed\n");
163		return val;
164	}
165
166	if (val & CMA3000_STATUS_PERR) {
167		dev_err(data->dev, "Parity Error\n");
168		return -EIO;
169	}
170
171	return 0;
172}
173
174static int cma3000_poweron(struct cma3000_accl_data *data)
175{
176	const struct cma3000_platform_data *pdata = data->pdata;
177	u8 ctrl = 0;
178	int ret;
179
180	if (data->g_range == CMARANGE_2G) {
181		ctrl = (data->mode << 1) | CMA3000_RANGE2G;
182	} else if (data->g_range == CMARANGE_8G) {
183		ctrl = (data->mode << 1) | CMA3000_RANGE8G;
184	} else {
185		dev_info(data->dev,
186			 "Invalid G range specified, assuming 8G\n");
187		ctrl = (data->mode << 1) | CMA3000_RANGE8G;
188	}
189
190	ctrl |= data->bus_ops->ctrl_mod;
191
192	CMA3000_SET(data, CMA3000_MDTHR, pdata->mdthr,
193		    "Motion Detect Threshold");
194	CMA3000_SET(data, CMA3000_MDFFTMR, pdata->mdfftmr,
195		    "Time register");
196	CMA3000_SET(data, CMA3000_FFTHR, pdata->ffthr,
197		    "Free fall threshold");
198	ret = CMA3000_SET(data, CMA3000_CTRL, ctrl, "Mode setting");
199	if (ret < 0)
200		return -EIO;
201
202	msleep(CMA3000_SETDELAY);
203
204	return 0;
205}
206
207static int cma3000_poweroff(struct cma3000_accl_data *data)
208{
209	int ret;
210
211	ret = CMA3000_SET(data, CMA3000_CTRL, CMAMODE_POFF, "Mode setting");
212	msleep(CMA3000_SETDELAY);
213
214	return ret;
215}
216
217static int cma3000_open(struct input_dev *input_dev)
218{
219	struct cma3000_accl_data *data = input_get_drvdata(input_dev);
220
221	guard(mutex)(&data->mutex);
222
223	if (!data->suspended)
224		cma3000_poweron(data);
225
226	data->opened = true;
227
228	return 0;
229}
230
231static void cma3000_close(struct input_dev *input_dev)
232{
233	struct cma3000_accl_data *data = input_get_drvdata(input_dev);
234
235	guard(mutex)(&data->mutex);
236
237	if (!data->suspended)
238		cma3000_poweroff(data);
239
240	data->opened = false;
241}
242
243void cma3000_suspend(struct cma3000_accl_data *data)
244{
245	guard(mutex)(&data->mutex);
246
247	if (!data->suspended && data->opened)
248		cma3000_poweroff(data);
249
250	data->suspended = true;
251}
252EXPORT_SYMBOL(cma3000_suspend);
253
254
255void cma3000_resume(struct cma3000_accl_data *data)
256{
257	guard(mutex)(&data->mutex);
258
259	if (data->suspended && data->opened)
260		cma3000_poweron(data);
261
262	data->suspended = false;
263}
264EXPORT_SYMBOL(cma3000_resume);
265
266struct cma3000_accl_data *cma3000_init(struct device *dev, int irq,
267				       const struct cma3000_bus_ops *bops)
268{
269	const struct cma3000_platform_data *pdata = dev_get_platdata(dev);
270	struct cma3000_accl_data *data;
271	struct input_dev *input_dev;
272	int rev;
273	int error;
274
275	if (!pdata) {
276		dev_err(dev, "platform data not found\n");
277		error = -EINVAL;
278		goto err_out;
279	}
280
281
282	/* if no IRQ return error */
283	if (irq == 0) {
284		error = -EINVAL;
285		goto err_out;
286	}
287
288	data = kzalloc(sizeof(*data), GFP_KERNEL);
289	input_dev = input_allocate_device();
290	if (!data || !input_dev) {
291		error = -ENOMEM;
292		goto err_free_mem;
293	}
294
295	data->dev = dev;
296	data->input_dev = input_dev;
297	data->bus_ops = bops;
298	data->pdata = pdata;
299	data->irq = irq;
300	mutex_init(&data->mutex);
301
302	data->mode = pdata->mode;
303	if (data->mode > CMAMODE_POFF) {
304		data->mode = CMAMODE_MOTDET;
305		dev_warn(dev,
306			 "Invalid mode specified, assuming Motion Detect\n");
307	}
308
309	data->g_range = pdata->g_range;
310	if (data->g_range != CMARANGE_2G && data->g_range != CMARANGE_8G) {
311		dev_info(dev,
312			 "Invalid G range specified, assuming 8G\n");
313		data->g_range = CMARANGE_8G;
314	}
315
316	input_dev->name = "cma3000-accelerometer";
317	input_dev->id.bustype = bops->bustype;
318	input_dev->open = cma3000_open;
319	input_dev->close = cma3000_close;
320
321	input_set_abs_params(input_dev, ABS_X,
322			-data->g_range, data->g_range, pdata->fuzz_x, 0);
323	input_set_abs_params(input_dev, ABS_Y,
324			-data->g_range, data->g_range, pdata->fuzz_y, 0);
325	input_set_abs_params(input_dev, ABS_Z,
326			-data->g_range, data->g_range, pdata->fuzz_z, 0);
327	input_set_abs_params(input_dev, ABS_MISC, 0, 1, 0, 0);
328
329	input_set_drvdata(input_dev, data);
330
331	error = cma3000_reset(data);
332	if (error)
333		goto err_free_mem;
334
335	rev = CMA3000_READ(data, CMA3000_REVID, "Revid");
336	if (rev < 0) {
337		error = rev;
338		goto err_free_mem;
339	}
340
341	pr_info("CMA3000 Accelerometer: Revision %x\n", rev);
342
343	error = request_threaded_irq(irq, NULL, cma3000_thread_irq,
344				     pdata->irqflags | IRQF_ONESHOT,
345				     "cma3000_d0x", data);
346	if (error) {
347		dev_err(dev, "request_threaded_irq failed\n");
348		goto err_free_mem;
349	}
350
351	error = input_register_device(data->input_dev);
352	if (error) {
353		dev_err(dev, "Unable to register input device\n");
354		goto err_free_irq;
355	}
356
357	return data;
358
359err_free_irq:
360	free_irq(irq, data);
361err_free_mem:
362	input_free_device(input_dev);
363	kfree(data);
364err_out:
365	return ERR_PTR(error);
366}
367EXPORT_SYMBOL(cma3000_init);
368
369void cma3000_exit(struct cma3000_accl_data *data)
370{
371	free_irq(data->irq, data);
372	input_unregister_device(data->input_dev);
373	kfree(data);
374}
375EXPORT_SYMBOL(cma3000_exit);
376
377MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver");
378MODULE_LICENSE("GPL");
379MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");