xref: /linux/drivers/input/misc/cma3000_d0x.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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/types.h>
10 #include <linux/interrupt.h>
11 #include <linux/delay.h>
12 #include <linux/slab.h>
13 #include <linux/input.h>
14 #include <linux/input/cma3000.h>
15 #include <linux/module.h>
16 
17 #include "cma3000_d0x.h"
18 
19 #define CMA3000_WHOAMI      0x00
20 #define CMA3000_REVID       0x01
21 #define CMA3000_CTRL        0x02
22 #define CMA3000_STATUS      0x03
23 #define CMA3000_RSTR        0x04
24 #define CMA3000_INTSTATUS   0x05
25 #define CMA3000_DOUTX       0x06
26 #define CMA3000_DOUTY       0x07
27 #define CMA3000_DOUTZ       0x08
28 #define CMA3000_MDTHR       0x09
29 #define CMA3000_MDFFTMR     0x0A
30 #define CMA3000_FFTHR       0x0B
31 
32 #define CMA3000_RANGE2G    (1 << 7)
33 #define CMA3000_RANGE8G    (0 << 7)
34 #define CMA3000_BUSI2C     (0 << 4)
35 #define CMA3000_MODEMASK   (7 << 1)
36 #define CMA3000_GRANGEMASK (1 << 7)
37 
38 #define CMA3000_STATUS_PERR    1
39 #define CMA3000_INTSTATUS_FFDET (1 << 2)
40 
41 /* Settling time delay in ms */
42 #define CMA3000_SETDELAY    30
43 
44 /* Delay for clearing interrupt in us */
45 #define CMA3000_INTDELAY    44
46 
47 
48 /*
49  * Bit weights in mg for bit 0, other bits need
50  * multiply factor 2^n. Eight bit is the sign bit.
51  */
52 #define BIT_TO_2G  18
53 #define BIT_TO_8G  71
54 
55 struct cma3000_accl_data {
56 	const struct cma3000_bus_ops *bus_ops;
57 	const struct cma3000_platform_data *pdata;
58 
59 	struct device *dev;
60 	struct input_dev *input_dev;
61 
62 	int bit_to_mg;
63 	int irq;
64 
65 	int g_range;
66 	u8 mode;
67 
68 	struct mutex mutex;
69 	bool opened;
70 	bool suspended;
71 };
72 
73 #define CMA3000_READ(data, reg, msg) \
74 	(data->bus_ops->read(data->dev, reg, msg))
75 #define CMA3000_SET(data, reg, val, msg) \
76 	((data)->bus_ops->write(data->dev, reg, val, msg))
77 
78 /*
79  * Conversion for each of the eight modes to g, depending
80  * on G range i.e 2G or 8G. Some modes always operate in
81  * 8G.
82  */
83 
84 static int mode_to_mg[8][2] = {
85 	{ 0, 0 },
86 	{ BIT_TO_8G, BIT_TO_2G },
87 	{ BIT_TO_8G, BIT_TO_2G },
88 	{ BIT_TO_8G, BIT_TO_8G },
89 	{ BIT_TO_8G, BIT_TO_8G },
90 	{ BIT_TO_8G, BIT_TO_2G },
91 	{ BIT_TO_8G, BIT_TO_2G },
92 	{ 0, 0},
93 };
94 
95 static void decode_mg(struct cma3000_accl_data *data, int *datax,
96 				int *datay, int *dataz)
97 {
98 	/* Data in 2's complement, convert to mg */
99 	*datax = ((s8)*datax) * data->bit_to_mg;
100 	*datay = ((s8)*datay) * data->bit_to_mg;
101 	*dataz = ((s8)*dataz) * data->bit_to_mg;
102 }
103 
104 static irqreturn_t cma3000_thread_irq(int irq, void *dev_id)
105 {
106 	struct cma3000_accl_data *data = dev_id;
107 	int datax, datay, dataz, intr_status;
108 	u8 ctrl, mode, range;
109 
110 	intr_status = CMA3000_READ(data, CMA3000_INTSTATUS, "interrupt status");
111 	if (intr_status < 0)
112 		return IRQ_NONE;
113 
114 	/* Check if free fall is detected, report immediately */
115 	if (intr_status & CMA3000_INTSTATUS_FFDET) {
116 		input_report_abs(data->input_dev, ABS_MISC, 1);
117 		input_sync(data->input_dev);
118 	} else {
119 		input_report_abs(data->input_dev, ABS_MISC, 0);
120 	}
121 
122 	datax = CMA3000_READ(data, CMA3000_DOUTX, "X");
123 	datay = CMA3000_READ(data, CMA3000_DOUTY, "Y");
124 	dataz = CMA3000_READ(data, CMA3000_DOUTZ, "Z");
125 
126 	ctrl = CMA3000_READ(data, CMA3000_CTRL, "ctrl");
127 	mode = (ctrl & CMA3000_MODEMASK) >> 1;
128 	range = (ctrl & CMA3000_GRANGEMASK) >> 7;
129 
130 	data->bit_to_mg = mode_to_mg[mode][range];
131 
132 	/* Interrupt not for this device */
133 	if (data->bit_to_mg == 0)
134 		return IRQ_NONE;
135 
136 	/* Decode register values to milli g */
137 	decode_mg(data, &datax, &datay, &dataz);
138 
139 	input_report_abs(data->input_dev, ABS_X, datax);
140 	input_report_abs(data->input_dev, ABS_Y, datay);
141 	input_report_abs(data->input_dev, ABS_Z, dataz);
142 	input_sync(data->input_dev);
143 
144 	return IRQ_HANDLED;
145 }
146 
147 static int cma3000_reset(struct cma3000_accl_data *data)
148 {
149 	int val;
150 
151 	/* Reset sequence */
152 	CMA3000_SET(data, CMA3000_RSTR, 0x02, "Reset");
153 	CMA3000_SET(data, CMA3000_RSTR, 0x0A, "Reset");
154 	CMA3000_SET(data, CMA3000_RSTR, 0x04, "Reset");
155 
156 	/* Settling time delay */
157 	mdelay(10);
158 
159 	val = CMA3000_READ(data, CMA3000_STATUS, "Status");
160 	if (val < 0) {
161 		dev_err(data->dev, "Reset failed\n");
162 		return val;
163 	}
164 
165 	if (val & CMA3000_STATUS_PERR) {
166 		dev_err(data->dev, "Parity Error\n");
167 		return -EIO;
168 	}
169 
170 	return 0;
171 }
172 
173 static int cma3000_poweron(struct cma3000_accl_data *data)
174 {
175 	const struct cma3000_platform_data *pdata = data->pdata;
176 	u8 ctrl = 0;
177 	int ret;
178 
179 	if (data->g_range == CMARANGE_2G) {
180 		ctrl = (data->mode << 1) | CMA3000_RANGE2G;
181 	} else if (data->g_range == CMARANGE_8G) {
182 		ctrl = (data->mode << 1) | CMA3000_RANGE8G;
183 	} else {
184 		dev_info(data->dev,
185 			 "Invalid G range specified, assuming 8G\n");
186 		ctrl = (data->mode << 1) | CMA3000_RANGE8G;
187 	}
188 
189 	ctrl |= data->bus_ops->ctrl_mod;
190 
191 	CMA3000_SET(data, CMA3000_MDTHR, pdata->mdthr,
192 		    "Motion Detect Threshold");
193 	CMA3000_SET(data, CMA3000_MDFFTMR, pdata->mdfftmr,
194 		    "Time register");
195 	CMA3000_SET(data, CMA3000_FFTHR, pdata->ffthr,
196 		    "Free fall threshold");
197 	ret = CMA3000_SET(data, CMA3000_CTRL, ctrl, "Mode setting");
198 	if (ret < 0)
199 		return -EIO;
200 
201 	msleep(CMA3000_SETDELAY);
202 
203 	return 0;
204 }
205 
206 static int cma3000_poweroff(struct cma3000_accl_data *data)
207 {
208 	int ret;
209 
210 	ret = CMA3000_SET(data, CMA3000_CTRL, CMAMODE_POFF, "Mode setting");
211 	msleep(CMA3000_SETDELAY);
212 
213 	return ret;
214 }
215 
216 static int cma3000_open(struct input_dev *input_dev)
217 {
218 	struct cma3000_accl_data *data = input_get_drvdata(input_dev);
219 
220 	guard(mutex)(&data->mutex);
221 
222 	if (!data->suspended)
223 		cma3000_poweron(data);
224 
225 	data->opened = true;
226 
227 	return 0;
228 }
229 
230 static void cma3000_close(struct input_dev *input_dev)
231 {
232 	struct cma3000_accl_data *data = input_get_drvdata(input_dev);
233 
234 	guard(mutex)(&data->mutex);
235 
236 	if (!data->suspended)
237 		cma3000_poweroff(data);
238 
239 	data->opened = false;
240 }
241 
242 void cma3000_suspend(struct cma3000_accl_data *data)
243 {
244 	guard(mutex)(&data->mutex);
245 
246 	if (!data->suspended && data->opened)
247 		cma3000_poweroff(data);
248 
249 	data->suspended = true;
250 }
251 EXPORT_SYMBOL(cma3000_suspend);
252 
253 
254 void cma3000_resume(struct cma3000_accl_data *data)
255 {
256 	guard(mutex)(&data->mutex);
257 
258 	if (data->suspended && data->opened)
259 		cma3000_poweron(data);
260 
261 	data->suspended = false;
262 }
263 EXPORT_SYMBOL(cma3000_resume);
264 
265 struct cma3000_accl_data *cma3000_init(struct device *dev, int irq,
266 				       const struct cma3000_bus_ops *bops)
267 {
268 	const struct cma3000_platform_data *pdata = dev_get_platdata(dev);
269 	struct cma3000_accl_data *data;
270 	struct input_dev *input_dev;
271 	int rev;
272 	int error;
273 
274 	if (!pdata) {
275 		dev_err(dev, "platform data not found\n");
276 		error = -EINVAL;
277 		goto err_out;
278 	}
279 
280 
281 	/* if no IRQ return error */
282 	if (irq == 0) {
283 		error = -EINVAL;
284 		goto err_out;
285 	}
286 
287 	data = kzalloc(sizeof(*data), GFP_KERNEL);
288 	input_dev = input_allocate_device();
289 	if (!data || !input_dev) {
290 		error = -ENOMEM;
291 		goto err_free_mem;
292 	}
293 
294 	data->dev = dev;
295 	data->input_dev = input_dev;
296 	data->bus_ops = bops;
297 	data->pdata = pdata;
298 	data->irq = irq;
299 	mutex_init(&data->mutex);
300 
301 	data->mode = pdata->mode;
302 	if (data->mode > CMAMODE_POFF) {
303 		data->mode = CMAMODE_MOTDET;
304 		dev_warn(dev,
305 			 "Invalid mode specified, assuming Motion Detect\n");
306 	}
307 
308 	data->g_range = pdata->g_range;
309 	if (data->g_range != CMARANGE_2G && data->g_range != CMARANGE_8G) {
310 		dev_info(dev,
311 			 "Invalid G range specified, assuming 8G\n");
312 		data->g_range = CMARANGE_8G;
313 	}
314 
315 	input_dev->name = "cma3000-accelerometer";
316 	input_dev->id.bustype = bops->bustype;
317 	input_dev->open = cma3000_open;
318 	input_dev->close = cma3000_close;
319 
320 	input_set_abs_params(input_dev, ABS_X,
321 			-data->g_range, data->g_range, pdata->fuzz_x, 0);
322 	input_set_abs_params(input_dev, ABS_Y,
323 			-data->g_range, data->g_range, pdata->fuzz_y, 0);
324 	input_set_abs_params(input_dev, ABS_Z,
325 			-data->g_range, data->g_range, pdata->fuzz_z, 0);
326 	input_set_abs_params(input_dev, ABS_MISC, 0, 1, 0, 0);
327 
328 	input_set_drvdata(input_dev, data);
329 
330 	error = cma3000_reset(data);
331 	if (error)
332 		goto err_free_mem;
333 
334 	rev = CMA3000_READ(data, CMA3000_REVID, "Revid");
335 	if (rev < 0) {
336 		error = rev;
337 		goto err_free_mem;
338 	}
339 
340 	pr_info("CMA3000 Accelerometer: Revision %x\n", rev);
341 
342 	error = request_threaded_irq(irq, NULL, cma3000_thread_irq,
343 				     pdata->irqflags | IRQF_ONESHOT,
344 				     "cma3000_d0x", data);
345 	if (error) {
346 		dev_err(dev, "request_threaded_irq failed\n");
347 		goto err_free_mem;
348 	}
349 
350 	error = input_register_device(data->input_dev);
351 	if (error) {
352 		dev_err(dev, "Unable to register input device\n");
353 		goto err_free_irq;
354 	}
355 
356 	return data;
357 
358 err_free_irq:
359 	free_irq(irq, data);
360 err_free_mem:
361 	input_free_device(input_dev);
362 	kfree(data);
363 err_out:
364 	return ERR_PTR(error);
365 }
366 EXPORT_SYMBOL(cma3000_init);
367 
368 void cma3000_exit(struct cma3000_accl_data *data)
369 {
370 	free_irq(data->irq, data);
371 	input_unregister_device(data->input_dev);
372 	kfree(data);
373 }
374 EXPORT_SYMBOL(cma3000_exit);
375 
376 MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver");
377 MODULE_LICENSE("GPL");
378 MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");
379