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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2011 Kionix, Inc.
  4 * Written by Chris Hudson <chudson@kionix.com>
  5 */
  6
  7#include <linux/delay.h>
  8#include <linux/i2c.h>
  9#include <linux/input.h>
 10#include <linux/interrupt.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/input/kxtj9.h>
 14
 15#define NAME			"kxtj9"
 16#define G_MAX			8000
 17/* OUTPUT REGISTERS */
 18#define XOUT_L			0x06
 19#define WHO_AM_I		0x0F
 20/* CONTROL REGISTERS */
 21#define INT_REL			0x1A
 22#define CTRL_REG1		0x1B
 23#define INT_CTRL1		0x1E
 24#define DATA_CTRL		0x21
 25/* CONTROL REGISTER 1 BITS */
 26#define PC1_OFF			0x7F
 27#define PC1_ON			(1 << 7)
 28/* Data ready function enable bit: set during probe if using irq mode */
 29#define DRDYE			(1 << 5)
 30/* DATA CONTROL REGISTER BITS */
 31#define ODR12_5F		0
 32#define ODR25F			1
 33#define ODR50F			2
 34#define ODR100F		3
 35#define ODR200F		4
 36#define ODR400F		5
 37#define ODR800F		6
 38/* INTERRUPT CONTROL REGISTER 1 BITS */
 39/* Set these during probe if using irq mode */
 40#define KXTJ9_IEL		(1 << 3)
 41#define KXTJ9_IEA		(1 << 4)
 42#define KXTJ9_IEN		(1 << 5)
 43/* INPUT_ABS CONSTANTS */
 44#define FUZZ			3
 45#define FLAT			3
 46/* RESUME STATE INDICES */
 47#define RES_DATA_CTRL		0
 48#define RES_CTRL_REG1		1
 49#define RES_INT_CTRL1		2
 50#define RESUME_ENTRIES		3
 51
 52/*
 53 * The following table lists the maximum appropriate poll interval for each
 54 * available output data rate.
 55 */
 56static const struct {
 57	unsigned int cutoff;
 58	u8 mask;
 59} kxtj9_odr_table[] = {
 60	{ 3,	ODR800F },
 61	{ 5,	ODR400F },
 62	{ 10,	ODR200F },
 63	{ 20,	ODR100F },
 64	{ 40,	ODR50F  },
 65	{ 80,	ODR25F  },
 66	{ 0,	ODR12_5F},
 67};
 68
 69struct kxtj9_data {
 70	struct i2c_client *client;
 71	struct kxtj9_platform_data pdata;
 72	struct input_dev *input_dev;
 73	unsigned int last_poll_interval;
 74	u8 shift;
 75	u8 ctrl_reg1;
 76	u8 data_ctrl;
 77	u8 int_ctrl;
 78};
 79
 80static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len)
 81{
 82	struct i2c_msg msgs[] = {
 83		{
 84			.addr = tj9->client->addr,
 85			.flags = tj9->client->flags,
 86			.len = 1,
 87			.buf = &addr,
 88		},
 89		{
 90			.addr = tj9->client->addr,
 91			.flags = tj9->client->flags | I2C_M_RD,
 92			.len = len,
 93			.buf = data,
 94		},
 95	};
 96
 97	return i2c_transfer(tj9->client->adapter, msgs, 2);
 98}
 99
100static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9)
101{
102	s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */
103	s16 x, y, z;
104	int err;
105
106	err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6);
107	if (err < 0)
108		dev_err(&tj9->client->dev, "accelerometer data read failed\n");
109
110	x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]);
111	y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]);
112	z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]);
113
114	x >>= tj9->shift;
115	y >>= tj9->shift;
116	z >>= tj9->shift;
117
118	input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x);
119	input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y);
120	input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z);
121	input_sync(tj9->input_dev);
122}
123
124static irqreturn_t kxtj9_isr(int irq, void *dev)
125{
126	struct kxtj9_data *tj9 = dev;
127	int err;
128
129	/* data ready is the only possible interrupt type */
130	kxtj9_report_acceleration_data(tj9);
131
132	err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
133	if (err < 0)
134		dev_err(&tj9->client->dev,
135			"error clearing interrupt status: %d\n", err);
136
137	return IRQ_HANDLED;
138}
139
140static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range)
141{
142	switch (new_g_range) {
143	case KXTJ9_G_2G:
144		tj9->shift = 4;
145		break;
146	case KXTJ9_G_4G:
147		tj9->shift = 3;
148		break;
149	case KXTJ9_G_8G:
150		tj9->shift = 2;
151		break;
152	default:
153		return -EINVAL;
154	}
155
156	tj9->ctrl_reg1 &= 0xe7;
157	tj9->ctrl_reg1 |= new_g_range;
158
159	return 0;
160}
161
162static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval)
163{
164	int err;
165	int i;
166
167	/* Use the lowest ODR that can support the requested poll interval */
168	for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) {
169		tj9->data_ctrl = kxtj9_odr_table[i].mask;
170		if (poll_interval < kxtj9_odr_table[i].cutoff)
171			break;
172	}
173
174	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
175	if (err < 0)
176		return err;
177
178	err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl);
179	if (err < 0)
180		return err;
181
182	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
183	if (err < 0)
184		return err;
185
186	return 0;
187}
188
189static int kxtj9_device_power_on(struct kxtj9_data *tj9)
190{
191	if (tj9->pdata.power_on)
192		return tj9->pdata.power_on();
193
194	return 0;
195}
196
197static void kxtj9_device_power_off(struct kxtj9_data *tj9)
198{
199	int err;
200
201	tj9->ctrl_reg1 &= PC1_OFF;
202	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
203	if (err < 0)
204		dev_err(&tj9->client->dev, "soft power off failed\n");
205
206	if (tj9->pdata.power_off)
207		tj9->pdata.power_off();
208}
209
210static int kxtj9_enable(struct kxtj9_data *tj9)
211{
212	int err;
213
214	err = kxtj9_device_power_on(tj9);
215	if (err < 0)
216		return err;
217
218	/* ensure that PC1 is cleared before updating control registers */
219	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
220	if (err < 0)
221		return err;
222
223	/* only write INT_CTRL_REG1 if in irq mode */
224	if (tj9->client->irq) {
225		err = i2c_smbus_write_byte_data(tj9->client,
226						INT_CTRL1, tj9->int_ctrl);
227		if (err < 0)
228			return err;
229	}
230
231	err = kxtj9_update_g_range(tj9, tj9->pdata.g_range);
232	if (err < 0)
233		return err;
234
235	/* turn on outputs */
236	tj9->ctrl_reg1 |= PC1_ON;
237	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
238	if (err < 0)
239		return err;
240
241	err = kxtj9_update_odr(tj9, tj9->last_poll_interval);
242	if (err < 0)
243		return err;
244
245	/* clear initial interrupt if in irq mode */
246	if (tj9->client->irq) {
247		err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
248		if (err < 0) {
249			dev_err(&tj9->client->dev,
250				"error clearing interrupt: %d\n", err);
251			goto fail;
252		}
253	}
254
255	return 0;
256
257fail:
258	kxtj9_device_power_off(tj9);
259	return err;
260}
261
262static void kxtj9_disable(struct kxtj9_data *tj9)
263{
264	kxtj9_device_power_off(tj9);
265}
266
267static int kxtj9_input_open(struct input_dev *input)
268{
269	struct kxtj9_data *tj9 = input_get_drvdata(input);
270
271	return kxtj9_enable(tj9);
272}
273
274static void kxtj9_input_close(struct input_dev *dev)
275{
276	struct kxtj9_data *tj9 = input_get_drvdata(dev);
277
278	kxtj9_disable(tj9);
279}
280
281/*
282 * When IRQ mode is selected, we need to provide an interface to allow the user
283 * to change the output data rate of the part.  For consistency, we are using
284 * the set_poll method, which accepts a poll interval in milliseconds, and then
285 * calls update_odr() while passing this value as an argument.  In IRQ mode, the
286 * data outputs will not be read AT the requested poll interval, rather, the
287 * lowest ODR that can support the requested interval.  The client application
288 * will be responsible for retrieving data from the input node at the desired
289 * interval.
290 */
291
292/* Returns currently selected poll interval (in ms) */
293static ssize_t kxtj9_get_poll(struct device *dev,
294				struct device_attribute *attr, char *buf)
295{
296	struct i2c_client *client = to_i2c_client(dev);
297	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
298
299	return sprintf(buf, "%d\n", tj9->last_poll_interval);
300}
301
302/* Allow users to select a new poll interval (in ms) */
303static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
304						const char *buf, size_t count)
305{
306	struct i2c_client *client = to_i2c_client(dev);
307	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
308	struct input_dev *input_dev = tj9->input_dev;
309	unsigned int interval;
310	int error;
311
312	error = kstrtouint(buf, 10, &interval);
313	if (error < 0)
314		return error;
315
316	/* Lock the device to prevent races with open/close (and itself) */
317	guard(mutex)(&input_dev->mutex);
318	guard(disable_irq)(&client->irq);
 
319
320	/*
321	 * Set current interval to the greater of the minimum interval or
322	 * the requested interval
323	 */
324	tj9->last_poll_interval = max(interval, tj9->pdata.min_interval);
325
326	kxtj9_update_odr(tj9, tj9->last_poll_interval);
327
 
 
 
328	return count;
329}
330
331static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll);
332
333static struct attribute *kxtj9_attrs[] = {
334	&dev_attr_poll.attr,
335	NULL
336};
337
338static umode_t kxtj9_attr_is_visible(struct kobject *kobj,
339				     struct attribute *attr, int n)
340{
341	struct device *dev = kobj_to_dev(kobj);
342	struct i2c_client *client = to_i2c_client(dev);
343
344	return client->irq ? attr->mode : 0;
345}
346
347static struct attribute_group kxtj9_group = {
348	.attrs = kxtj9_attrs,
349	.is_visible = kxtj9_attr_is_visible,
350};
351__ATTRIBUTE_GROUPS(kxtj9);
352
353static void kxtj9_poll(struct input_dev *input)
354{
355	struct kxtj9_data *tj9 = input_get_drvdata(input);
356	unsigned int poll_interval = input_get_poll_interval(input);
357
358	kxtj9_report_acceleration_data(tj9);
359
360	if (poll_interval != tj9->last_poll_interval) {
361		kxtj9_update_odr(tj9, poll_interval);
362		tj9->last_poll_interval = poll_interval;
363	}
364}
365
366static void kxtj9_platform_exit(void *data)
367{
368	struct kxtj9_data *tj9 = data;
369
370	if (tj9->pdata.exit)
371		tj9->pdata.exit();
372}
373
374static int kxtj9_verify(struct kxtj9_data *tj9)
375{
376	int retval;
377
378	retval = kxtj9_device_power_on(tj9);
379	if (retval < 0)
380		return retval;
381
382	retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I);
383	if (retval < 0) {
384		dev_err(&tj9->client->dev, "read err int source\n");
385		goto out;
386	}
387
388	retval = (retval != 0x07 && retval != 0x08) ? -EIO : 0;
389
390out:
391	kxtj9_device_power_off(tj9);
392	return retval;
393}
394
395static int kxtj9_probe(struct i2c_client *client)
 
396{
397	const struct kxtj9_platform_data *pdata =
398			dev_get_platdata(&client->dev);
399	struct kxtj9_data *tj9;
400	struct input_dev *input_dev;
401	int err;
402
403	if (!i2c_check_functionality(client->adapter,
404				I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) {
405		dev_err(&client->dev, "client is not i2c capable\n");
406		return -ENXIO;
407	}
408
409	if (!pdata) {
410		dev_err(&client->dev, "platform data is NULL; exiting\n");
411		return -EINVAL;
412	}
413
414	tj9 = devm_kzalloc(&client->dev, sizeof(*tj9), GFP_KERNEL);
415	if (!tj9) {
416		dev_err(&client->dev,
417			"failed to allocate memory for module data\n");
418		return -ENOMEM;
419	}
420
421	tj9->client = client;
422	tj9->pdata = *pdata;
423
424	if (pdata->init) {
425		err = pdata->init();
426		if (err < 0)
427			return err;
428	}
429
430	err = devm_add_action_or_reset(&client->dev, kxtj9_platform_exit, tj9);
431	if (err)
432		return err;
433
434	err = kxtj9_verify(tj9);
435	if (err < 0) {
436		dev_err(&client->dev, "device not recognized\n");
437		return err;
438	}
439
440	i2c_set_clientdata(client, tj9);
441
442	tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range;
443	tj9->last_poll_interval = tj9->pdata.init_interval;
444
445	input_dev = devm_input_allocate_device(&client->dev);
446	if (!input_dev) {
447		dev_err(&client->dev, "input device allocate failed\n");
448		return -ENOMEM;
449	}
450
451	input_set_drvdata(input_dev, tj9);
452	tj9->input_dev = input_dev;
453
454	input_dev->name = "kxtj9_accel";
455	input_dev->id.bustype = BUS_I2C;
456
457	input_dev->open = kxtj9_input_open;
458	input_dev->close = kxtj9_input_close;
459
460	input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT);
461	input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT);
462	input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT);
463
464	if (client->irq <= 0) {
465		err = input_setup_polling(input_dev, kxtj9_poll);
466		if (err)
467			return err;
468	}
469
470	err = input_register_device(input_dev);
471	if (err) {
472		dev_err(&client->dev,
473			"unable to register input polled device %s: %d\n",
474			input_dev->name, err);
475		return err;
476	}
477
478	if (client->irq) {
479		/* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */
480		tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL;
481		tj9->ctrl_reg1 |= DRDYE;
482
483		err = devm_request_threaded_irq(&client->dev, client->irq,
484						NULL, kxtj9_isr,
485						IRQF_TRIGGER_RISING |
486							IRQF_ONESHOT,
487						"kxtj9-irq", tj9);
488		if (err) {
489			dev_err(&client->dev, "request irq failed: %d\n", err);
490			return err;
491		}
 
 
 
 
 
 
 
492	}
493
494	return 0;
495}
496
497static int kxtj9_suspend(struct device *dev)
498{
499	struct i2c_client *client = to_i2c_client(dev);
500	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
501	struct input_dev *input_dev = tj9->input_dev;
502
503	guard(mutex)(&input_dev->mutex);
504
505	if (input_device_enabled(input_dev))
506		kxtj9_disable(tj9);
507
 
508	return 0;
509}
510
511static int kxtj9_resume(struct device *dev)
512{
513	struct i2c_client *client = to_i2c_client(dev);
514	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
515	struct input_dev *input_dev = tj9->input_dev;
516
517	guard(mutex)(&input_dev->mutex);
518
519	if (input_device_enabled(input_dev))
520		kxtj9_enable(tj9);
521
 
522	return 0;
523}
524
525static DEFINE_SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);
526
527static const struct i2c_device_id kxtj9_id[] = {
528	{ NAME },
529	{ }
530};
531
532MODULE_DEVICE_TABLE(i2c, kxtj9_id);
533
534static struct i2c_driver kxtj9_driver = {
535	.driver = {
536		.name		= NAME,
537		.dev_groups	= kxtj9_groups,
538		.pm		= pm_sleep_ptr(&kxtj9_pm_ops),
539	},
540	.probe		= kxtj9_probe,
541	.id_table	= kxtj9_id,
542};
543
544module_i2c_driver(kxtj9_driver);
545
546MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
547MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
548MODULE_LICENSE("GPL");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2011 Kionix, Inc.
  4 * Written by Chris Hudson <chudson@kionix.com>
  5 */
  6
  7#include <linux/delay.h>
  8#include <linux/i2c.h>
  9#include <linux/input.h>
 10#include <linux/interrupt.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/input/kxtj9.h>
 14
 15#define NAME			"kxtj9"
 16#define G_MAX			8000
 17/* OUTPUT REGISTERS */
 18#define XOUT_L			0x06
 19#define WHO_AM_I		0x0F
 20/* CONTROL REGISTERS */
 21#define INT_REL			0x1A
 22#define CTRL_REG1		0x1B
 23#define INT_CTRL1		0x1E
 24#define DATA_CTRL		0x21
 25/* CONTROL REGISTER 1 BITS */
 26#define PC1_OFF			0x7F
 27#define PC1_ON			(1 << 7)
 28/* Data ready funtion enable bit: set during probe if using irq mode */
 29#define DRDYE			(1 << 5)
 30/* DATA CONTROL REGISTER BITS */
 31#define ODR12_5F		0
 32#define ODR25F			1
 33#define ODR50F			2
 34#define ODR100F		3
 35#define ODR200F		4
 36#define ODR400F		5
 37#define ODR800F		6
 38/* INTERRUPT CONTROL REGISTER 1 BITS */
 39/* Set these during probe if using irq mode */
 40#define KXTJ9_IEL		(1 << 3)
 41#define KXTJ9_IEA		(1 << 4)
 42#define KXTJ9_IEN		(1 << 5)
 43/* INPUT_ABS CONSTANTS */
 44#define FUZZ			3
 45#define FLAT			3
 46/* RESUME STATE INDICES */
 47#define RES_DATA_CTRL		0
 48#define RES_CTRL_REG1		1
 49#define RES_INT_CTRL1		2
 50#define RESUME_ENTRIES		3
 51
 52/*
 53 * The following table lists the maximum appropriate poll interval for each
 54 * available output data rate.
 55 */
 56static const struct {
 57	unsigned int cutoff;
 58	u8 mask;
 59} kxtj9_odr_table[] = {
 60	{ 3,	ODR800F },
 61	{ 5,	ODR400F },
 62	{ 10,	ODR200F },
 63	{ 20,	ODR100F },
 64	{ 40,	ODR50F  },
 65	{ 80,	ODR25F  },
 66	{ 0,	ODR12_5F},
 67};
 68
 69struct kxtj9_data {
 70	struct i2c_client *client;
 71	struct kxtj9_platform_data pdata;
 72	struct input_dev *input_dev;
 73	unsigned int last_poll_interval;
 74	u8 shift;
 75	u8 ctrl_reg1;
 76	u8 data_ctrl;
 77	u8 int_ctrl;
 78};
 79
 80static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len)
 81{
 82	struct i2c_msg msgs[] = {
 83		{
 84			.addr = tj9->client->addr,
 85			.flags = tj9->client->flags,
 86			.len = 1,
 87			.buf = &addr,
 88		},
 89		{
 90			.addr = tj9->client->addr,
 91			.flags = tj9->client->flags | I2C_M_RD,
 92			.len = len,
 93			.buf = data,
 94		},
 95	};
 96
 97	return i2c_transfer(tj9->client->adapter, msgs, 2);
 98}
 99
100static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9)
101{
102	s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */
103	s16 x, y, z;
104	int err;
105
106	err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6);
107	if (err < 0)
108		dev_err(&tj9->client->dev, "accelerometer data read failed\n");
109
110	x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]);
111	y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]);
112	z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]);
113
114	x >>= tj9->shift;
115	y >>= tj9->shift;
116	z >>= tj9->shift;
117
118	input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x);
119	input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y);
120	input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z);
121	input_sync(tj9->input_dev);
122}
123
124static irqreturn_t kxtj9_isr(int irq, void *dev)
125{
126	struct kxtj9_data *tj9 = dev;
127	int err;
128
129	/* data ready is the only possible interrupt type */
130	kxtj9_report_acceleration_data(tj9);
131
132	err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
133	if (err < 0)
134		dev_err(&tj9->client->dev,
135			"error clearing interrupt status: %d\n", err);
136
137	return IRQ_HANDLED;
138}
139
140static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range)
141{
142	switch (new_g_range) {
143	case KXTJ9_G_2G:
144		tj9->shift = 4;
145		break;
146	case KXTJ9_G_4G:
147		tj9->shift = 3;
148		break;
149	case KXTJ9_G_8G:
150		tj9->shift = 2;
151		break;
152	default:
153		return -EINVAL;
154	}
155
156	tj9->ctrl_reg1 &= 0xe7;
157	tj9->ctrl_reg1 |= new_g_range;
158
159	return 0;
160}
161
162static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval)
163{
164	int err;
165	int i;
166
167	/* Use the lowest ODR that can support the requested poll interval */
168	for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) {
169		tj9->data_ctrl = kxtj9_odr_table[i].mask;
170		if (poll_interval < kxtj9_odr_table[i].cutoff)
171			break;
172	}
173
174	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
175	if (err < 0)
176		return err;
177
178	err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl);
179	if (err < 0)
180		return err;
181
182	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
183	if (err < 0)
184		return err;
185
186	return 0;
187}
188
189static int kxtj9_device_power_on(struct kxtj9_data *tj9)
190{
191	if (tj9->pdata.power_on)
192		return tj9->pdata.power_on();
193
194	return 0;
195}
196
197static void kxtj9_device_power_off(struct kxtj9_data *tj9)
198{
199	int err;
200
201	tj9->ctrl_reg1 &= PC1_OFF;
202	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
203	if (err < 0)
204		dev_err(&tj9->client->dev, "soft power off failed\n");
205
206	if (tj9->pdata.power_off)
207		tj9->pdata.power_off();
208}
209
210static int kxtj9_enable(struct kxtj9_data *tj9)
211{
212	int err;
213
214	err = kxtj9_device_power_on(tj9);
215	if (err < 0)
216		return err;
217
218	/* ensure that PC1 is cleared before updating control registers */
219	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
220	if (err < 0)
221		return err;
222
223	/* only write INT_CTRL_REG1 if in irq mode */
224	if (tj9->client->irq) {
225		err = i2c_smbus_write_byte_data(tj9->client,
226						INT_CTRL1, tj9->int_ctrl);
227		if (err < 0)
228			return err;
229	}
230
231	err = kxtj9_update_g_range(tj9, tj9->pdata.g_range);
232	if (err < 0)
233		return err;
234
235	/* turn on outputs */
236	tj9->ctrl_reg1 |= PC1_ON;
237	err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
238	if (err < 0)
239		return err;
240
241	err = kxtj9_update_odr(tj9, tj9->last_poll_interval);
242	if (err < 0)
243		return err;
244
245	/* clear initial interrupt if in irq mode */
246	if (tj9->client->irq) {
247		err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
248		if (err < 0) {
249			dev_err(&tj9->client->dev,
250				"error clearing interrupt: %d\n", err);
251			goto fail;
252		}
253	}
254
255	return 0;
256
257fail:
258	kxtj9_device_power_off(tj9);
259	return err;
260}
261
262static void kxtj9_disable(struct kxtj9_data *tj9)
263{
264	kxtj9_device_power_off(tj9);
265}
266
267static int kxtj9_input_open(struct input_dev *input)
268{
269	struct kxtj9_data *tj9 = input_get_drvdata(input);
270
271	return kxtj9_enable(tj9);
272}
273
274static void kxtj9_input_close(struct input_dev *dev)
275{
276	struct kxtj9_data *tj9 = input_get_drvdata(dev);
277
278	kxtj9_disable(tj9);
279}
280
281/*
282 * When IRQ mode is selected, we need to provide an interface to allow the user
283 * to change the output data rate of the part.  For consistency, we are using
284 * the set_poll method, which accepts a poll interval in milliseconds, and then
285 * calls update_odr() while passing this value as an argument.  In IRQ mode, the
286 * data outputs will not be read AT the requested poll interval, rather, the
287 * lowest ODR that can support the requested interval.  The client application
288 * will be responsible for retrieving data from the input node at the desired
289 * interval.
290 */
291
292/* Returns currently selected poll interval (in ms) */
293static ssize_t kxtj9_get_poll(struct device *dev,
294				struct device_attribute *attr, char *buf)
295{
296	struct i2c_client *client = to_i2c_client(dev);
297	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
298
299	return sprintf(buf, "%d\n", tj9->last_poll_interval);
300}
301
302/* Allow users to select a new poll interval (in ms) */
303static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
304						const char *buf, size_t count)
305{
306	struct i2c_client *client = to_i2c_client(dev);
307	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
308	struct input_dev *input_dev = tj9->input_dev;
309	unsigned int interval;
310	int error;
311
312	error = kstrtouint(buf, 10, &interval);
313	if (error < 0)
314		return error;
315
316	/* Lock the device to prevent races with open/close (and itself) */
317	mutex_lock(&input_dev->mutex);
318
319	disable_irq(client->irq);
320
321	/*
322	 * Set current interval to the greater of the minimum interval or
323	 * the requested interval
324	 */
325	tj9->last_poll_interval = max(interval, tj9->pdata.min_interval);
326
327	kxtj9_update_odr(tj9, tj9->last_poll_interval);
328
329	enable_irq(client->irq);
330	mutex_unlock(&input_dev->mutex);
331
332	return count;
333}
334
335static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll);
336
337static struct attribute *kxtj9_attributes[] = {
338	&dev_attr_poll.attr,
339	NULL
340};
341
342static struct attribute_group kxtj9_attribute_group = {
343	.attrs = kxtj9_attributes
 
 
 
 
 
 
 
 
 
 
344};
 
345
346static void kxtj9_poll(struct input_dev *input)
347{
348	struct kxtj9_data *tj9 = input_get_drvdata(input);
349	unsigned int poll_interval = input_get_poll_interval(input);
350
351	kxtj9_report_acceleration_data(tj9);
352
353	if (poll_interval != tj9->last_poll_interval) {
354		kxtj9_update_odr(tj9, poll_interval);
355		tj9->last_poll_interval = poll_interval;
356	}
357}
358
359static void kxtj9_platform_exit(void *data)
360{
361	struct kxtj9_data *tj9 = data;
362
363	if (tj9->pdata.exit)
364		tj9->pdata.exit();
365}
366
367static int kxtj9_verify(struct kxtj9_data *tj9)
368{
369	int retval;
370
371	retval = kxtj9_device_power_on(tj9);
372	if (retval < 0)
373		return retval;
374
375	retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I);
376	if (retval < 0) {
377		dev_err(&tj9->client->dev, "read err int source\n");
378		goto out;
379	}
380
381	retval = (retval != 0x07 && retval != 0x08) ? -EIO : 0;
382
383out:
384	kxtj9_device_power_off(tj9);
385	return retval;
386}
387
388static int kxtj9_probe(struct i2c_client *client,
389		       const struct i2c_device_id *id)
390{
391	const struct kxtj9_platform_data *pdata =
392			dev_get_platdata(&client->dev);
393	struct kxtj9_data *tj9;
394	struct input_dev *input_dev;
395	int err;
396
397	if (!i2c_check_functionality(client->adapter,
398				I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) {
399		dev_err(&client->dev, "client is not i2c capable\n");
400		return -ENXIO;
401	}
402
403	if (!pdata) {
404		dev_err(&client->dev, "platform data is NULL; exiting\n");
405		return -EINVAL;
406	}
407
408	tj9 = devm_kzalloc(&client->dev, sizeof(*tj9), GFP_KERNEL);
409	if (!tj9) {
410		dev_err(&client->dev,
411			"failed to allocate memory for module data\n");
412		return -ENOMEM;
413	}
414
415	tj9->client = client;
416	tj9->pdata = *pdata;
417
418	if (pdata->init) {
419		err = pdata->init();
420		if (err < 0)
421			return err;
422	}
423
424	err = devm_add_action_or_reset(&client->dev, kxtj9_platform_exit, tj9);
425	if (err)
426		return err;
427
428	err = kxtj9_verify(tj9);
429	if (err < 0) {
430		dev_err(&client->dev, "device not recognized\n");
431		return err;
432	}
433
434	i2c_set_clientdata(client, tj9);
435
436	tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range;
437	tj9->last_poll_interval = tj9->pdata.init_interval;
438
439	input_dev = devm_input_allocate_device(&client->dev);
440	if (!input_dev) {
441		dev_err(&client->dev, "input device allocate failed\n");
442		return -ENOMEM;
443	}
444
445	input_set_drvdata(input_dev, tj9);
446	tj9->input_dev = input_dev;
447
448	input_dev->name = "kxtj9_accel";
449	input_dev->id.bustype = BUS_I2C;
450
451	input_dev->open = kxtj9_input_open;
452	input_dev->close = kxtj9_input_close;
453
454	input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT);
455	input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT);
456	input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT);
457
458	if (client->irq <= 0) {
459		err = input_setup_polling(input_dev, kxtj9_poll);
460		if (err)
461			return err;
462	}
463
464	err = input_register_device(input_dev);
465	if (err) {
466		dev_err(&client->dev,
467			"unable to register input polled device %s: %d\n",
468			input_dev->name, err);
469		return err;
470	}
471
472	if (client->irq) {
473		/* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */
474		tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL;
475		tj9->ctrl_reg1 |= DRDYE;
476
477		err = devm_request_threaded_irq(&client->dev, client->irq,
478						NULL, kxtj9_isr,
479						IRQF_TRIGGER_RISING |
480							IRQF_ONESHOT,
481						"kxtj9-irq", tj9);
482		if (err) {
483			dev_err(&client->dev, "request irq failed: %d\n", err);
484			return err;
485		}
486
487		err = devm_device_add_group(&client->dev,
488					    &kxtj9_attribute_group);
489		if (err) {
490			dev_err(&client->dev, "sysfs create failed: %d\n", err);
491			return err;
492		}
493	}
494
495	return 0;
496}
497
498static int __maybe_unused kxtj9_suspend(struct device *dev)
499{
500	struct i2c_client *client = to_i2c_client(dev);
501	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
502	struct input_dev *input_dev = tj9->input_dev;
503
504	mutex_lock(&input_dev->mutex);
505
506	if (input_dev->users)
507		kxtj9_disable(tj9);
508
509	mutex_unlock(&input_dev->mutex);
510	return 0;
511}
512
513static int __maybe_unused kxtj9_resume(struct device *dev)
514{
515	struct i2c_client *client = to_i2c_client(dev);
516	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
517	struct input_dev *input_dev = tj9->input_dev;
518
519	mutex_lock(&input_dev->mutex);
520
521	if (input_dev->users)
522		kxtj9_enable(tj9);
523
524	mutex_unlock(&input_dev->mutex);
525	return 0;
526}
527
528static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);
529
530static const struct i2c_device_id kxtj9_id[] = {
531	{ NAME, 0 },
532	{ },
533};
534
535MODULE_DEVICE_TABLE(i2c, kxtj9_id);
536
537static struct i2c_driver kxtj9_driver = {
538	.driver = {
539		.name	= NAME,
540		.pm	= &kxtj9_pm_ops,
 
541	},
542	.probe		= kxtj9_probe,
543	.id_table	= kxtj9_id,
544};
545
546module_i2c_driver(kxtj9_driver);
547
548MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
549MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
550MODULE_LICENSE("GPL");