1 /*
2  * Common code for Freescale MMA955x Intelligent Sensor Platform drivers
3  * Copyright (c) 2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/i2c.h>
17 #include <linux/delay.h>
18 #include <linux/iio/iio.h>
19 #include <linux/pm_runtime.h>
20 #include "mma9551_core.h"
21 
22 /* Command masks for mailbox write command */
23 #define MMA9551_CMD_READ_VERSION_INFO	0x00
24 #define MMA9551_CMD_READ_CONFIG		0x10
25 #define MMA9551_CMD_WRITE_CONFIG	0x20
26 #define MMA9551_CMD_READ_STATUS		0x30
27 
28 /* Mailbox read command */
29 #define MMA9551_RESPONSE_COCO		BIT(7)
30 
31 /* Error-Status codes returned in mailbox read command */
32 #define MMA9551_MCI_ERROR_NONE			0x00
33 #define MMA9551_MCI_ERROR_PARAM			0x04
34 #define MMA9551_MCI_INVALID_COUNT		0x19
35 #define MMA9551_MCI_ERROR_COMMAND		0x1C
36 #define MMA9551_MCI_ERROR_INVALID_LENGTH	0x21
37 #define MMA9551_MCI_ERROR_FIFO_BUSY		0x22
38 #define MMA9551_MCI_ERROR_FIFO_ALLOCATED	0x23
39 #define MMA9551_MCI_ERROR_FIFO_OVERSIZE		0x24
40 
41 /* GPIO Application */
42 #define MMA9551_GPIO_POL_MSB		0x08
43 #define MMA9551_GPIO_POL_LSB		0x09
44 
45 /* Sleep/Wake application */
46 #define MMA9551_SLEEP_CFG		0x06
47 #define MMA9551_SLEEP_CFG_SNCEN		BIT(0)
48 #define MMA9551_SLEEP_CFG_FLEEN		BIT(1)
49 #define MMA9551_SLEEP_CFG_SCHEN		BIT(2)
50 
51 /* AFE application */
52 #define MMA9551_AFE_X_ACCEL_REG		0x00
53 #define MMA9551_AFE_Y_ACCEL_REG		0x02
54 #define MMA9551_AFE_Z_ACCEL_REG		0x04
55 
56 /* Reset/Suspend/Clear application */
57 #define MMA9551_RSC_RESET		0x00
58 #define MMA9551_RSC_OFFSET(mask)	(3 - (ffs(mask) - 1) / 8)
59 #define MMA9551_RSC_VAL(mask)		(mask >> (((ffs(mask) - 1) / 8) * 8))
60 
61 /*
62  * A response is composed of:
63  * - control registers: MB0-3
64  * - data registers: MB4-31
65  *
66  * A request is composed of:
67  * - mbox to write to (always 0)
68  * - control registers: MB1-4
69  * - data registers: MB5-31
70  */
71 #define MMA9551_MAILBOX_CTRL_REGS	4
72 #define MMA9551_MAX_MAILBOX_DATA_REGS	28
73 #define MMA9551_MAILBOX_REGS		32
74 
75 #define MMA9551_I2C_READ_RETRIES	5
76 #define MMA9551_I2C_READ_DELAY	50	/* us */
77 
78 struct mma9551_mbox_request {
79 	u8 start_mbox;		/* Always 0. */
80 	u8 app_id;
81 	/*
82 	 * See Section 5.3.1 of the MMA955xL Software Reference Manual.
83 	 *
84 	 * Bit 7: reserved, always 0
85 	 * Bits 6-4: command
86 	 * Bits 3-0: upper bits of register offset
87 	 */
88 	u8 cmd_off;
89 	u8 lower_off;
90 	u8 nbytes;
91 	u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS - 1];
92 } __packed;
93 
94 struct mma9551_mbox_response {
95 	u8 app_id;
96 	/*
97 	 * See Section 5.3.3 of the MMA955xL Software Reference Manual.
98 	 *
99 	 * Bit 7: COCO
100 	 * Bits 6-0: Error code.
101 	 */
102 	u8 coco_err;
103 	u8 nbytes;
104 	u8 req_bytes;
105 	u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS];
106 } __packed;
107 
108 struct mma9551_version_info {
109 	__be32 device_id;
110 	u8 rom_version[2];
111 	u8 fw_version[2];
112 	u8 hw_version[2];
113 	u8 fw_build[2];
114 };
115 
mma9551_transfer(struct i2c_client * client,u8 app_id,u8 command,u16 offset,u8 * inbytes,int num_inbytes,u8 * outbytes,int num_outbytes)116 static int mma9551_transfer(struct i2c_client *client,
117 			    u8 app_id, u8 command, u16 offset,
118 			    u8 *inbytes, int num_inbytes,
119 			    u8 *outbytes, int num_outbytes)
120 {
121 	struct mma9551_mbox_request req;
122 	struct mma9551_mbox_response rsp;
123 	struct i2c_msg in, out;
124 	u8 req_len, err_code;
125 	int ret, retries;
126 
127 	if (offset >= 1 << 12) {
128 		dev_err(&client->dev, "register offset too large\n");
129 		return -EINVAL;
130 	}
131 
132 	req_len = 1 + MMA9551_MAILBOX_CTRL_REGS + num_inbytes;
133 	req.start_mbox = 0;
134 	req.app_id = app_id;
135 	req.cmd_off = command | (offset >> 8);
136 	req.lower_off = offset;
137 
138 	if (command == MMA9551_CMD_WRITE_CONFIG)
139 		req.nbytes = num_inbytes;
140 	else
141 		req.nbytes = num_outbytes;
142 	if (num_inbytes)
143 		memcpy(req.buf, inbytes, num_inbytes);
144 
145 	out.addr = client->addr;
146 	out.flags = 0;
147 	out.len = req_len;
148 	out.buf = (u8 *)&req;
149 
150 	ret = i2c_transfer(client->adapter, &out, 1);
151 	if (ret < 0) {
152 		dev_err(&client->dev, "i2c write failed\n");
153 		return ret;
154 	}
155 
156 	retries = MMA9551_I2C_READ_RETRIES;
157 	do {
158 		udelay(MMA9551_I2C_READ_DELAY);
159 
160 		in.addr = client->addr;
161 		in.flags = I2C_M_RD;
162 		in.len = sizeof(rsp);
163 		in.buf = (u8 *)&rsp;
164 
165 		ret = i2c_transfer(client->adapter, &in, 1);
166 		if (ret < 0) {
167 			dev_err(&client->dev, "i2c read failed\n");
168 			return ret;
169 		}
170 
171 		if (rsp.coco_err & MMA9551_RESPONSE_COCO)
172 			break;
173 	} while (--retries > 0);
174 
175 	if (retries == 0) {
176 		dev_err(&client->dev,
177 			"timed out while waiting for command response\n");
178 		return -ETIMEDOUT;
179 	}
180 
181 	if (rsp.app_id != app_id) {
182 		dev_err(&client->dev,
183 			"app_id mismatch in response got %02x expected %02x\n",
184 			rsp.app_id, app_id);
185 		return -EINVAL;
186 	}
187 
188 	err_code = rsp.coco_err & ~MMA9551_RESPONSE_COCO;
189 	if (err_code != MMA9551_MCI_ERROR_NONE) {
190 		dev_err(&client->dev, "read returned error %x\n", err_code);
191 		return -EINVAL;
192 	}
193 
194 	if (rsp.nbytes != rsp.req_bytes) {
195 		dev_err(&client->dev,
196 			"output length mismatch got %d expected %d\n",
197 			rsp.nbytes, rsp.req_bytes);
198 		return -EINVAL;
199 	}
200 
201 	if (num_outbytes)
202 		memcpy(outbytes, rsp.buf, num_outbytes);
203 
204 	return 0;
205 }
206 
207 /**
208  * mma9551_read_config_byte() - read 1 configuration byte
209  * @client:	I2C client
210  * @app_id:	Application ID
211  * @reg:	Application register
212  * @val:	Pointer to store value read
213  *
214  * Read one configuration byte from the device using MMA955xL command format.
215  * Commands to the MMA955xL platform consist of a write followed
216  * by one or more reads.
217  *
218  * Locking note: This function must be called with the device lock held.
219  * Locking is not handled inside the function. Callers should ensure they
220  * serialize access to the HW.
221  *
222  * Returns: 0 on success, negative value on failure.
223  */
mma9551_read_config_byte(struct i2c_client * client,u8 app_id,u16 reg,u8 * val)224 int mma9551_read_config_byte(struct i2c_client *client, u8 app_id,
225 			     u16 reg, u8 *val)
226 {
227 	return mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
228 				reg, NULL, 0, val, 1);
229 }
230 EXPORT_SYMBOL(mma9551_read_config_byte);
231 
232 /**
233  * mma9551_write_config_byte() - write 1 configuration byte
234  * @client:	I2C client
235  * @app_id:	Application ID
236  * @reg:	Application register
237  * @val:	Value to write
238  *
239  * Write one configuration byte from the device using MMA955xL command format.
240  * Commands to the MMA955xL platform consist of a write followed by one or
241  * more reads.
242  *
243  * Locking note: This function must be called with the device lock held.
244  * Locking is not handled inside the function. Callers should ensure they
245  * serialize access to the HW.
246  *
247  * Returns: 0 on success, negative value on failure.
248  */
mma9551_write_config_byte(struct i2c_client * client,u8 app_id,u16 reg,u8 val)249 int mma9551_write_config_byte(struct i2c_client *client, u8 app_id,
250 			      u16 reg, u8 val)
251 {
252 	return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
253 				&val, 1, NULL, 0);
254 }
255 EXPORT_SYMBOL(mma9551_write_config_byte);
256 
257 /**
258  * mma9551_read_status_byte() - read 1 status byte
259  * @client:	I2C client
260  * @app_id:	Application ID
261  * @reg:	Application register
262  * @val:	Pointer to store value read
263  *
264  * Read one status byte from the device using MMA955xL command format.
265  * Commands to the MMA955xL platform consist of a write followed by one or
266  * more reads.
267  *
268  * Locking note: This function must be called with the device lock held.
269  * Locking is not handled inside the function. Callers should ensure they
270  * serialize access to the HW.
271  *
272  * Returns: 0 on success, negative value on failure.
273  */
mma9551_read_status_byte(struct i2c_client * client,u8 app_id,u16 reg,u8 * val)274 int mma9551_read_status_byte(struct i2c_client *client, u8 app_id,
275 			     u16 reg, u8 *val)
276 {
277 	return mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
278 				reg, NULL, 0, val, 1);
279 }
280 EXPORT_SYMBOL(mma9551_read_status_byte);
281 
282 /**
283  * mma9551_read_config_word() - read 1 config word
284  * @client:	I2C client
285  * @app_id:	Application ID
286  * @reg:	Application register
287  * @val:	Pointer to store value read
288  *
289  * Read one configuration word from the device using MMA955xL command format.
290  * Commands to the MMA955xL platform consist of a write followed by one or
291  * more reads.
292  *
293  * Locking note: This function must be called with the device lock held.
294  * Locking is not handled inside the function. Callers should ensure they
295  * serialize access to the HW.
296  *
297  * Returns: 0 on success, negative value on failure.
298  */
mma9551_read_config_word(struct i2c_client * client,u8 app_id,u16 reg,u16 * val)299 int mma9551_read_config_word(struct i2c_client *client, u8 app_id,
300 			     u16 reg, u16 *val)
301 {
302 	int ret;
303 	__be16 v;
304 
305 	ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
306 			       reg, NULL, 0, (u8 *)&v, 2);
307 	if (ret < 0)
308 		return ret;
309 
310 	*val = be16_to_cpu(v);
311 
312 	return 0;
313 }
314 EXPORT_SYMBOL(mma9551_read_config_word);
315 
316 /**
317  * mma9551_write_config_word() - write 1 config word
318  * @client:	I2C client
319  * @app_id:	Application ID
320  * @reg:	Application register
321  * @val:	Value to write
322  *
323  * Write one configuration word from the device using MMA955xL command format.
324  * Commands to the MMA955xL platform consist of a write followed by one or
325  * more reads.
326  *
327  * Locking note: This function must be called with the device lock held.
328  * Locking is not handled inside the function. Callers should ensure they
329  * serialize access to the HW.
330  *
331  * Returns: 0 on success, negative value on failure.
332  */
mma9551_write_config_word(struct i2c_client * client,u8 app_id,u16 reg,u16 val)333 int mma9551_write_config_word(struct i2c_client *client, u8 app_id,
334 			      u16 reg, u16 val)
335 {
336 	__be16 v = cpu_to_be16(val);
337 
338 	return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
339 				(u8 *)&v, 2, NULL, 0);
340 }
341 EXPORT_SYMBOL(mma9551_write_config_word);
342 
343 /**
344  * mma9551_read_status_word() - read 1 status word
345  * @client:	I2C client
346  * @app_id:	Application ID
347  * @reg:	Application register
348  * @val:	Pointer to store value read
349  *
350  * Read one status word from the device using MMA955xL command format.
351  * Commands to the MMA955xL platform consist of a write followed by one or
352  * more reads.
353  *
354  * Locking note: This function must be called with the device lock held.
355  * Locking is not handled inside the function. Callers should ensure they
356  * serialize access to the HW.
357  *
358  * Returns: 0 on success, negative value on failure.
359  */
mma9551_read_status_word(struct i2c_client * client,u8 app_id,u16 reg,u16 * val)360 int mma9551_read_status_word(struct i2c_client *client, u8 app_id,
361 			     u16 reg, u16 *val)
362 {
363 	int ret;
364 	__be16 v;
365 
366 	ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
367 			       reg, NULL, 0, (u8 *)&v, 2);
368 	if (ret < 0)
369 		return ret;
370 
371 	*val = be16_to_cpu(v);
372 
373 	return 0;
374 }
375 EXPORT_SYMBOL(mma9551_read_status_word);
376 
377 /**
378  * mma9551_read_config_words() - read multiple config words
379  * @client:	I2C client
380  * @app_id:	Application ID
381  * @reg:	Application register
382  * @len:	Length of array to read (in words)
383  * @buf:	Array of words to read
384  *
385  * Read multiple configuration registers (word-sized registers).
386  *
387  * Locking note: This function must be called with the device lock held.
388  * Locking is not handled inside the function. Callers should ensure they
389  * serialize access to the HW.
390  *
391  * Returns: 0 on success, negative value on failure.
392  */
mma9551_read_config_words(struct i2c_client * client,u8 app_id,u16 reg,u8 len,u16 * buf)393 int mma9551_read_config_words(struct i2c_client *client, u8 app_id,
394 			      u16 reg, u8 len, u16 *buf)
395 {
396 	int ret, i;
397 	__be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
398 
399 	if (len > ARRAY_SIZE(be_buf)) {
400 		dev_err(&client->dev, "Invalid buffer size %d\n", len);
401 		return -EINVAL;
402 	}
403 
404 	ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
405 			       reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
406 	if (ret < 0)
407 		return ret;
408 
409 	for (i = 0; i < len; i++)
410 		buf[i] = be16_to_cpu(be_buf[i]);
411 
412 	return 0;
413 }
414 EXPORT_SYMBOL(mma9551_read_config_words);
415 
416 /**
417  * mma9551_read_status_words() - read multiple status words
418  * @client:	I2C client
419  * @app_id:	Application ID
420  * @reg:	Application register
421  * @len:	Length of array to read (in words)
422  * @buf:	Array of words to read
423  *
424  * Read multiple status registers (word-sized registers).
425  *
426  * Locking note: This function must be called with the device lock held.
427  * Locking is not handled inside the function. Callers should ensure they
428  * serialize access to the HW.
429  *
430  * Returns: 0 on success, negative value on failure.
431  */
mma9551_read_status_words(struct i2c_client * client,u8 app_id,u16 reg,u8 len,u16 * buf)432 int mma9551_read_status_words(struct i2c_client *client, u8 app_id,
433 			      u16 reg, u8 len, u16 *buf)
434 {
435 	int ret, i;
436 	__be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
437 
438 	if (len > ARRAY_SIZE(be_buf)) {
439 		dev_err(&client->dev, "Invalid buffer size %d\n", len);
440 		return -EINVAL;
441 	}
442 
443 	ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
444 			       reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
445 	if (ret < 0)
446 		return ret;
447 
448 	for (i = 0; i < len; i++)
449 		buf[i] = be16_to_cpu(be_buf[i]);
450 
451 	return 0;
452 }
453 EXPORT_SYMBOL(mma9551_read_status_words);
454 
455 /**
456  * mma9551_write_config_words() - write multiple config words
457  * @client:	I2C client
458  * @app_id:	Application ID
459  * @reg:	Application register
460  * @len:	Length of array to write (in words)
461  * @buf:	Array of words to write
462  *
463  * Write multiple configuration registers (word-sized registers).
464  *
465  * Locking note: This function must be called with the device lock held.
466  * Locking is not handled inside the function. Callers should ensure they
467  * serialize access to the HW.
468  *
469  * Returns: 0 on success, negative value on failure.
470  */
mma9551_write_config_words(struct i2c_client * client,u8 app_id,u16 reg,u8 len,u16 * buf)471 int mma9551_write_config_words(struct i2c_client *client, u8 app_id,
472 			       u16 reg, u8 len, u16 *buf)
473 {
474 	int i;
475 	__be16 be_buf[(MMA9551_MAX_MAILBOX_DATA_REGS - 1) / 2];
476 
477 	if (len > ARRAY_SIZE(be_buf)) {
478 		dev_err(&client->dev, "Invalid buffer size %d\n", len);
479 		return -EINVAL;
480 	}
481 
482 	for (i = 0; i < len; i++)
483 		be_buf[i] = cpu_to_be16(buf[i]);
484 
485 	return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG,
486 				reg, (u8 *)be_buf, len * sizeof(u16), NULL, 0);
487 }
488 EXPORT_SYMBOL(mma9551_write_config_words);
489 
490 /**
491  * mma9551_update_config_bits() - update bits in register
492  * @client:	I2C client
493  * @app_id:	Application ID
494  * @reg:	Application register
495  * @mask:	Mask for the bits to update
496  * @val:	Value of the bits to update
497  *
498  * Update bits in the given register using a bit mask.
499  *
500  * Locking note: This function must be called with the device lock held.
501  * Locking is not handled inside the function. Callers should ensure they
502  * serialize access to the HW.
503  *
504  * Returns: 0 on success, negative value on failure.
505  */
mma9551_update_config_bits(struct i2c_client * client,u8 app_id,u16 reg,u8 mask,u8 val)506 int mma9551_update_config_bits(struct i2c_client *client, u8 app_id,
507 			       u16 reg, u8 mask, u8 val)
508 {
509 	int ret;
510 	u8 tmp, orig;
511 
512 	ret = mma9551_read_config_byte(client, app_id, reg, &orig);
513 	if (ret < 0)
514 		return ret;
515 
516 	tmp = orig & ~mask;
517 	tmp |= val & mask;
518 
519 	if (tmp == orig)
520 		return 0;
521 
522 	return mma9551_write_config_byte(client, app_id, reg, tmp);
523 }
524 EXPORT_SYMBOL(mma9551_update_config_bits);
525 
526 /**
527  * mma9551_gpio_config() - configure gpio
528  * @client:	I2C client
529  * @pin:	GPIO pin to configure
530  * @app_id:	Application ID
531  * @bitnum:	Bit number of status register being assigned to the GPIO pin.
532  * @polarity:	The polarity parameter is described in section 6.2.2, page 66,
533  *		of the Software Reference Manual.  Basically, polarity=0 means
534  *		the interrupt line has the same value as the selected bit,
535  *		while polarity=1 means the line is inverted.
536  *
537  * Assign a bit from an application’s status register to a specific GPIO pin.
538  *
539  * Locking note: This function must be called with the device lock held.
540  * Locking is not handled inside the function. Callers should ensure they
541  * serialize access to the HW.
542  *
543  * Returns: 0 on success, negative value on failure.
544  */
mma9551_gpio_config(struct i2c_client * client,enum mma9551_gpio_pin pin,u8 app_id,u8 bitnum,int polarity)545 int mma9551_gpio_config(struct i2c_client *client, enum mma9551_gpio_pin pin,
546 			u8 app_id, u8 bitnum, int polarity)
547 {
548 	u8 reg, pol_mask, pol_val;
549 	int ret;
550 
551 	if (pin > mma9551_gpio_max) {
552 		dev_err(&client->dev, "bad GPIO pin\n");
553 		return -EINVAL;
554 	}
555 
556 	/*
557 	 * Pin 6 is configured by regs 0x00 and 0x01, pin 7 by 0x02 and
558 	 * 0x03, and so on.
559 	 */
560 	reg = pin * 2;
561 
562 	ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
563 					reg, app_id);
564 	if (ret < 0) {
565 		dev_err(&client->dev, "error setting GPIO app_id\n");
566 		return ret;
567 	}
568 
569 	ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
570 					reg + 1, bitnum);
571 	if (ret < 0) {
572 		dev_err(&client->dev, "error setting GPIO bit number\n");
573 		return ret;
574 	}
575 
576 	switch (pin) {
577 	case mma9551_gpio6:
578 		reg = MMA9551_GPIO_POL_LSB;
579 		pol_mask = 1 << 6;
580 		break;
581 	case mma9551_gpio7:
582 		reg = MMA9551_GPIO_POL_LSB;
583 		pol_mask = 1 << 7;
584 		break;
585 	case mma9551_gpio8:
586 		reg = MMA9551_GPIO_POL_MSB;
587 		pol_mask = 1 << 0;
588 		break;
589 	case mma9551_gpio9:
590 		reg = MMA9551_GPIO_POL_MSB;
591 		pol_mask = 1 << 1;
592 		break;
593 	}
594 	pol_val = polarity ? pol_mask : 0;
595 
596 	ret = mma9551_update_config_bits(client, MMA9551_APPID_GPIO, reg,
597 					 pol_mask, pol_val);
598 	if (ret < 0)
599 		dev_err(&client->dev, "error setting GPIO polarity\n");
600 
601 	return ret;
602 }
603 EXPORT_SYMBOL(mma9551_gpio_config);
604 
605 /**
606  * mma9551_read_version() - read device version information
607  * @client:	I2C client
608  *
609  * Read version information and print device id and firmware version.
610  *
611  * Locking note: This function must be called with the device lock held.
612  * Locking is not handled inside the function. Callers should ensure they
613  * serialize access to the HW.
614  *
615  * Returns: 0 on success, negative value on failure.
616  */
mma9551_read_version(struct i2c_client * client)617 int mma9551_read_version(struct i2c_client *client)
618 {
619 	struct mma9551_version_info info;
620 	int ret;
621 
622 	ret = mma9551_transfer(client, MMA9551_APPID_VERSION, 0x00, 0x00,
623 			       NULL, 0, (u8 *)&info, sizeof(info));
624 	if (ret < 0)
625 		return ret;
626 
627 	dev_info(&client->dev, "device ID 0x%x, firmware version %02x.%02x\n",
628 		 be32_to_cpu(info.device_id), info.fw_version[0],
629 		 info.fw_version[1]);
630 
631 	return 0;
632 }
633 EXPORT_SYMBOL(mma9551_read_version);
634 
635 /**
636  * mma9551_set_device_state() - sets HW power mode
637  * @client:	I2C client
638  * @enable:	Use true to power on device, false to cause the device
639  *		to enter sleep.
640  *
641  * Set power on/off for device using the Sleep/Wake Application.
642  * When enable is true, power on chip and enable doze mode.
643  * When enable is false, enter sleep mode (device remains in the
644  * lowest-power mode).
645  *
646  * Locking note: This function must be called with the device lock held.
647  * Locking is not handled inside the function. Callers should ensure they
648  * serialize access to the HW.
649  *
650  * Returns: 0 on success, negative value on failure.
651  */
mma9551_set_device_state(struct i2c_client * client,bool enable)652 int mma9551_set_device_state(struct i2c_client *client, bool enable)
653 {
654 	return mma9551_update_config_bits(client, MMA9551_APPID_SLEEP_WAKE,
655 					  MMA9551_SLEEP_CFG,
656 					  MMA9551_SLEEP_CFG_SNCEN |
657 					  MMA9551_SLEEP_CFG_FLEEN |
658 					  MMA9551_SLEEP_CFG_SCHEN,
659 					  enable ? MMA9551_SLEEP_CFG_SCHEN |
660 					  MMA9551_SLEEP_CFG_FLEEN :
661 					  MMA9551_SLEEP_CFG_SNCEN);
662 }
663 EXPORT_SYMBOL(mma9551_set_device_state);
664 
665 /**
666  * mma9551_set_power_state() - sets runtime PM state
667  * @client:	I2C client
668  * @on:		Use true to power on device, false to power off
669  *
670  * Resume or suspend the device using Runtime PM.
671  * The device will suspend after the autosuspend delay.
672  *
673  * Returns: 0 on success, negative value on failure.
674  */
mma9551_set_power_state(struct i2c_client * client,bool on)675 int mma9551_set_power_state(struct i2c_client *client, bool on)
676 {
677 #ifdef CONFIG_PM
678 	int ret;
679 
680 	if (on)
681 		ret = pm_runtime_get_sync(&client->dev);
682 	else {
683 		pm_runtime_mark_last_busy(&client->dev);
684 		ret = pm_runtime_put_autosuspend(&client->dev);
685 	}
686 
687 	if (ret < 0) {
688 		dev_err(&client->dev,
689 			"failed to change power state to %d\n", on);
690 		if (on)
691 			pm_runtime_put_noidle(&client->dev);
692 
693 		return ret;
694 	}
695 #endif
696 
697 	return 0;
698 }
699 EXPORT_SYMBOL(mma9551_set_power_state);
700 
701 /**
702  * mma9551_sleep() - sleep
703  * @freq:	Application frequency
704  *
705  * Firmware applications run at a certain frequency on the
706  * device. Sleep for one application cycle to make sure the
707  * application had time to run once and initialize set values.
708  */
mma9551_sleep(int freq)709 void mma9551_sleep(int freq)
710 {
711 	int sleep_val = 1000 / freq;
712 
713 	if (sleep_val < 20)
714 		usleep_range(sleep_val * 1000, 20000);
715 	else
716 		msleep_interruptible(sleep_val);
717 }
718 EXPORT_SYMBOL(mma9551_sleep);
719 
720 /**
721  * mma9551_read_accel_chan() - read accelerometer channel
722  * @client:	I2C client
723  * @chan:	IIO channel
724  * @val:	Pointer to the accelerometer value read
725  * @val2:	Unused
726  *
727  * Read accelerometer value for the specified channel.
728  *
729  * Locking note: This function must be called with the device lock held.
730  * Locking is not handled inside the function. Callers should ensure they
731  * serialize access to the HW.
732  *
733  * Returns: IIO_VAL_INT on success, negative value on failure.
734  */
mma9551_read_accel_chan(struct i2c_client * client,const struct iio_chan_spec * chan,int * val,int * val2)735 int mma9551_read_accel_chan(struct i2c_client *client,
736 			    const struct iio_chan_spec *chan,
737 			    int *val, int *val2)
738 {
739 	u16 reg_addr;
740 	s16 raw_accel;
741 	int ret;
742 
743 	switch (chan->channel2) {
744 	case IIO_MOD_X:
745 		reg_addr = MMA9551_AFE_X_ACCEL_REG;
746 		break;
747 	case IIO_MOD_Y:
748 		reg_addr = MMA9551_AFE_Y_ACCEL_REG;
749 		break;
750 	case IIO_MOD_Z:
751 		reg_addr = MMA9551_AFE_Z_ACCEL_REG;
752 		break;
753 	default:
754 		return -EINVAL;
755 	}
756 
757 	ret = mma9551_set_power_state(client, true);
758 	if (ret < 0)
759 		return ret;
760 
761 	ret = mma9551_read_status_word(client, MMA9551_APPID_AFE,
762 				       reg_addr, &raw_accel);
763 	if (ret < 0)
764 		goto out_poweroff;
765 
766 	*val = raw_accel;
767 
768 	ret = IIO_VAL_INT;
769 
770 out_poweroff:
771 	mma9551_set_power_state(client, false);
772 	return ret;
773 }
774 EXPORT_SYMBOL(mma9551_read_accel_chan);
775 
776 /**
777  * mma9551_read_accel_scale() - read accelerometer scale
778  * @val:	Pointer to the accelerometer scale (int value)
779  * @val2:	Pointer to the accelerometer scale (micro value)
780  *
781  * Read accelerometer scale.
782  *
783  * Returns: IIO_VAL_INT_PLUS_MICRO.
784  */
mma9551_read_accel_scale(int * val,int * val2)785 int mma9551_read_accel_scale(int *val, int *val2)
786 {
787 	*val = 0;
788 	*val2 = 2440;
789 
790 	return IIO_VAL_INT_PLUS_MICRO;
791 }
792 EXPORT_SYMBOL(mma9551_read_accel_scale);
793 
794 /**
795  * mma9551_app_reset() - reset application
796  * @client:	I2C client
797  * @app_mask:	Application to reset
798  *
799  * Reset the given application (using the Reset/Suspend/Clear
800  * Control Application)
801  *
802  * Returns: 0 on success, negative value on failure.
803  */
mma9551_app_reset(struct i2c_client * client,u32 app_mask)804 int mma9551_app_reset(struct i2c_client *client, u32 app_mask)
805 {
806 	return mma9551_write_config_byte(client, MMA9551_APPID_RSC,
807 					 MMA9551_RSC_RESET +
808 					 MMA9551_RSC_OFFSET(app_mask),
809 					 MMA9551_RSC_VAL(app_mask));
810 }
811 EXPORT_SYMBOL(mma9551_app_reset);
812 
813 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
814 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
815 MODULE_LICENSE("GPL v2");
816 MODULE_DESCRIPTION("MMA955xL sensors core");
817