524 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			524 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
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| /*
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|  * kxsd9.c	simple support for the Kionix KXSD9 3D
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|  *		accelerometer.
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|  *
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|  * Copyright (c) 2008-2009 Jonathan Cameron <jic23@kernel.org>
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|  *
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|  * The i2c interface is very similar, so shouldn't be a problem once
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|  * I have a suitable wire made up.
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|  *
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|  * TODO:	Support the motion detector
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|  */
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| 
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| #include <linux/device.h>
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| #include <linux/kernel.h>
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| #include <linux/sysfs.h>
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| #include <linux/slab.h>
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| #include <linux/module.h>
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| #include <linux/regmap.h>
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| #include <linux/bitops.h>
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| #include <linux/delay.h>
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| #include <linux/regulator/consumer.h>
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| #include <linux/pm_runtime.h>
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| #include <linux/iio/iio.h>
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| #include <linux/iio/sysfs.h>
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| #include <linux/iio/buffer.h>
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| #include <linux/iio/triggered_buffer.h>
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| #include <linux/iio/trigger_consumer.h>
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| 
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| #include "kxsd9.h"
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| 
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| #define KXSD9_REG_X		0x00
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| #define KXSD9_REG_Y		0x02
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| #define KXSD9_REG_Z		0x04
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| #define KXSD9_REG_AUX		0x06
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| #define KXSD9_REG_RESET		0x0a
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| #define KXSD9_REG_CTRL_C	0x0c
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| 
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| #define KXSD9_CTRL_C_FS_MASK	0x03
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| #define KXSD9_CTRL_C_FS_8G	0x00
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| #define KXSD9_CTRL_C_FS_6G	0x01
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| #define KXSD9_CTRL_C_FS_4G	0x02
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| #define KXSD9_CTRL_C_FS_2G	0x03
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| #define KXSD9_CTRL_C_MOT_LAT	BIT(3)
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| #define KXSD9_CTRL_C_MOT_LEV	BIT(4)
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| #define KXSD9_CTRL_C_LP_MASK	0xe0
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| #define KXSD9_CTRL_C_LP_NONE	0x00
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| #define KXSD9_CTRL_C_LP_2000HZC	BIT(5)
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| #define KXSD9_CTRL_C_LP_2000HZB	BIT(6)
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| #define KXSD9_CTRL_C_LP_2000HZA	(BIT(5)|BIT(6))
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| #define KXSD9_CTRL_C_LP_1000HZ	BIT(7)
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| #define KXSD9_CTRL_C_LP_500HZ	(BIT(7)|BIT(5))
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| #define KXSD9_CTRL_C_LP_100HZ	(BIT(7)|BIT(6))
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| #define KXSD9_CTRL_C_LP_50HZ	(BIT(7)|BIT(6)|BIT(5))
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| 
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| #define KXSD9_REG_CTRL_B	0x0d
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| 
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| #define KXSD9_CTRL_B_CLK_HLD	BIT(7)
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| #define KXSD9_CTRL_B_ENABLE	BIT(6)
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| #define KXSD9_CTRL_B_ST		BIT(5) /* Self-test */
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| 
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| #define KXSD9_REG_CTRL_A	0x0e
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| 
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| /**
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|  * struct kxsd9_state - device related storage
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|  * @dev: pointer to the parent device
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|  * @map: regmap to the device
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|  * @orientation: mounting matrix, flipped axis etc
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|  * @regs: regulators for this device, VDD and IOVDD
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|  * @scale: the current scaling setting
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|  */
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| struct kxsd9_state {
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| 	struct device *dev;
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| 	struct regmap *map;
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| 	struct iio_mount_matrix orientation;
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| 	struct regulator_bulk_data regs[2];
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| 	u8 scale;
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| };
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| 
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| #define KXSD9_SCALE_2G "0.011978"
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| #define KXSD9_SCALE_4G "0.023927"
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| #define KXSD9_SCALE_6G "0.035934"
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| #define KXSD9_SCALE_8G "0.047853"
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| 
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| /* reverse order */
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| static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 };
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| 
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| #define KXSD9_ZERO_G_OFFSET -2048
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| 
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| /*
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|  * Regulator names
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|  */
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| static const char kxsd9_reg_vdd[] = "vdd";
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| static const char kxsd9_reg_iovdd[] = "iovdd";
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| 
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| static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
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| {
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| 	int ret, i;
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 	bool foundit = false;
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| 
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| 	for (i = 0; i < 4; i++)
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| 		if (micro == kxsd9_micro_scales[i]) {
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| 			foundit = true;
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| 			break;
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| 		}
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| 	if (!foundit)
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| 		return -EINVAL;
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| 
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| 	ret = regmap_update_bits(st->map,
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| 				 KXSD9_REG_CTRL_C,
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| 				 KXSD9_CTRL_C_FS_MASK,
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| 				 i);
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| 	if (ret < 0)
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| 		goto error_ret;
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| 
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| 	/* Cached scale when the sensor is powered down */
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| 	st->scale = i;
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| 
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| error_ret:
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| 	return ret;
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| }
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| 
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| static IIO_CONST_ATTR(accel_scale_available,
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| 		KXSD9_SCALE_2G " "
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| 		KXSD9_SCALE_4G " "
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| 		KXSD9_SCALE_6G " "
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| 		KXSD9_SCALE_8G);
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| 
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| static struct attribute *kxsd9_attributes[] = {
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| 	&iio_const_attr_accel_scale_available.dev_attr.attr,
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| 	NULL,
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| };
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| 
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| static int kxsd9_write_raw(struct iio_dev *indio_dev,
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| 			   struct iio_chan_spec const *chan,
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| 			   int val,
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| 			   int val2,
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| 			   long mask)
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| {
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| 	int ret = -EINVAL;
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 
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| 	pm_runtime_get_sync(st->dev);
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| 
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| 	if (mask == IIO_CHAN_INFO_SCALE) {
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| 		/* Check no integer component */
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| 		if (val)
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| 			return -EINVAL;
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| 		ret = kxsd9_write_scale(indio_dev, val2);
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| 	}
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| 
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| 	pm_runtime_mark_last_busy(st->dev);
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| 	pm_runtime_put_autosuspend(st->dev);
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| 
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| 	return ret;
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| }
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| 
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| static int kxsd9_read_raw(struct iio_dev *indio_dev,
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| 			  struct iio_chan_spec const *chan,
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| 			  int *val, int *val2, long mask)
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| {
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| 	int ret = -EINVAL;
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 	unsigned int regval;
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| 	__be16 raw_val;
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| 	u16 nval;
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| 
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| 	pm_runtime_get_sync(st->dev);
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| 
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| 	switch (mask) {
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| 	case IIO_CHAN_INFO_RAW:
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| 		ret = regmap_bulk_read(st->map, chan->address, &raw_val,
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| 				       sizeof(raw_val));
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| 		if (ret)
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| 			goto error_ret;
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| 		nval = be16_to_cpu(raw_val);
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| 		/* Only 12 bits are valid */
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| 		nval >>= 4;
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| 		*val = nval;
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| 		ret = IIO_VAL_INT;
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| 		break;
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| 	case IIO_CHAN_INFO_OFFSET:
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| 		/* This has a bias of -2048 */
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| 		*val = KXSD9_ZERO_G_OFFSET;
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| 		ret = IIO_VAL_INT;
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| 		break;
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| 	case IIO_CHAN_INFO_SCALE:
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| 		ret = regmap_read(st->map,
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| 				  KXSD9_REG_CTRL_C,
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| 				  ®val);
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| 		if (ret < 0)
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| 			goto error_ret;
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| 		*val = 0;
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| 		*val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK];
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| 		ret = IIO_VAL_INT_PLUS_MICRO;
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| 		break;
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| 	}
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| 
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| error_ret:
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| 	pm_runtime_mark_last_busy(st->dev);
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| 	pm_runtime_put_autosuspend(st->dev);
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| 
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| 	return ret;
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| };
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| 
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| static irqreturn_t kxsd9_trigger_handler(int irq, void *p)
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| {
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| 	const struct iio_poll_func *pf = p;
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| 	struct iio_dev *indio_dev = pf->indio_dev;
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 	/*
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| 	 * Ensure correct positioning and alignment of timestamp.
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| 	 * No need to zero initialize as all elements written.
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| 	 */
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| 	struct {
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| 		__be16 chan[4];
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| 		s64 ts __aligned(8);
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| 	} hw_values;
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| 	int ret;
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| 
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| 	ret = regmap_bulk_read(st->map,
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| 			       KXSD9_REG_X,
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| 			       hw_values.chan,
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| 			       sizeof(hw_values.chan));
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| 	if (ret) {
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| 		dev_err(st->dev, "error reading data: %d\n", ret);
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| 		goto out;
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| 	}
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| 
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| 	iio_push_to_buffers_with_timestamp(indio_dev,
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| 					   &hw_values,
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| 					   iio_get_time_ns(indio_dev));
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| out:
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| 	iio_trigger_notify_done(indio_dev->trig);
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| 
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| 	return IRQ_HANDLED;
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| }
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| 
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| static int kxsd9_buffer_preenable(struct iio_dev *indio_dev)
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| {
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 
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| 	pm_runtime_get_sync(st->dev);
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| 
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| 	return 0;
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| }
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| 
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| static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev)
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| {
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 
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| 	pm_runtime_mark_last_busy(st->dev);
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| 	pm_runtime_put_autosuspend(st->dev);
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| 
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| 	return 0;
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| }
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| 
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| static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = {
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| 	.preenable = kxsd9_buffer_preenable,
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| 	.postdisable = kxsd9_buffer_postdisable,
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| };
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| 
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| static const struct iio_mount_matrix *
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| kxsd9_get_mount_matrix(const struct iio_dev *indio_dev,
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| 		       const struct iio_chan_spec *chan)
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| {
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 
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| 	return &st->orientation;
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| }
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| 
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| static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = {
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| 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix),
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| 	{ },
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| };
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| 
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| #define KXSD9_ACCEL_CHAN(axis, index)						\
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| 	{								\
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| 		.type = IIO_ACCEL,					\
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| 		.modified = 1,						\
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| 		.channel2 = IIO_MOD_##axis,				\
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| 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
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| 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
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| 					BIT(IIO_CHAN_INFO_OFFSET),	\
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| 		.ext_info = kxsd9_ext_info,				\
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| 		.address = KXSD9_REG_##axis,				\
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| 		.scan_index = index,					\
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| 		.scan_type = {                                          \
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| 			.sign = 'u',					\
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| 			.realbits = 12,					\
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| 			.storagebits = 16,				\
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| 			.shift = 4,					\
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| 			.endianness = IIO_BE,				\
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| 		},							\
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| 	}
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| 
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| static const struct iio_chan_spec kxsd9_channels[] = {
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| 	KXSD9_ACCEL_CHAN(X, 0),
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| 	KXSD9_ACCEL_CHAN(Y, 1),
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| 	KXSD9_ACCEL_CHAN(Z, 2),
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| 	{
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| 		.type = IIO_VOLTAGE,
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| 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
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| 		.indexed = 1,
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| 		.address = KXSD9_REG_AUX,
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| 		.scan_index = 3,
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| 		.scan_type = {
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| 			.sign = 'u',
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| 			.realbits = 12,
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| 			.storagebits = 16,
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| 			.shift = 4,
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| 			.endianness = IIO_BE,
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| 		},
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| 	},
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| 	IIO_CHAN_SOFT_TIMESTAMP(4),
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| };
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| 
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| static const struct attribute_group kxsd9_attribute_group = {
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| 	.attrs = kxsd9_attributes,
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| };
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| 
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| static int kxsd9_power_up(struct kxsd9_state *st)
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| {
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| 	int ret;
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| 
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| 	/* Enable the regulators */
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| 	ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs);
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| 	if (ret) {
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| 		dev_err(st->dev, "Cannot enable regulators\n");
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| 		return ret;
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| 	}
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| 
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| 	/* Power up */
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| 	ret = regmap_write(st->map,
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| 			   KXSD9_REG_CTRL_B,
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| 			   KXSD9_CTRL_B_ENABLE);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/*
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| 	 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g,
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| 	 * latched wakeup
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| 	 */
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| 	ret = regmap_write(st->map,
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| 			   KXSD9_REG_CTRL_C,
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| 			   KXSD9_CTRL_C_LP_1000HZ |
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| 			   KXSD9_CTRL_C_MOT_LEV	|
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| 			   KXSD9_CTRL_C_MOT_LAT |
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| 			   st->scale);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/*
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| 	 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's
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| 	 * set 20 ms to allow for some slack.
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| 	 */
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| 	msleep(20);
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| 
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| 	return 0;
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| };
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| 
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| static int kxsd9_power_down(struct kxsd9_state *st)
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| {
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| 	int ret;
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| 
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| 	/*
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| 	 * Set into low power mode - since there may be more users of the
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| 	 * regulators this is the first step of the power saving: it will
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| 	 * make sure we conserve power even if there are others users on the
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| 	 * regulators.
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| 	 */
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| 	ret = regmap_update_bits(st->map,
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| 				 KXSD9_REG_CTRL_B,
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| 				 KXSD9_CTRL_B_ENABLE,
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| 				 0);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/* Disable the regulators */
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| 	ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs);
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| 	if (ret) {
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| 		dev_err(st->dev, "Cannot disable regulators\n");
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| 		return ret;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static const struct iio_info kxsd9_info = {
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| 	.read_raw = &kxsd9_read_raw,
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| 	.write_raw = &kxsd9_write_raw,
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| 	.attrs = &kxsd9_attribute_group,
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| };
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| 
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| /* Four channels apart from timestamp, scan mask = 0x0f */
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| static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
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| 
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| int kxsd9_common_probe(struct device *dev,
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| 		       struct regmap *map,
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| 		       const char *name)
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| {
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| 	struct iio_dev *indio_dev;
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| 	struct kxsd9_state *st;
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| 	int ret;
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| 
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| 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
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| 	if (!indio_dev)
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| 		return -ENOMEM;
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| 
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| 	st = iio_priv(indio_dev);
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| 	st->dev = dev;
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| 	st->map = map;
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| 
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| 	indio_dev->channels = kxsd9_channels;
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| 	indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
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| 	indio_dev->name = name;
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| 	indio_dev->info = &kxsd9_info;
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| 	indio_dev->modes = INDIO_DIRECT_MODE;
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| 	indio_dev->available_scan_masks = kxsd9_scan_masks;
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| 
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| 	/* Read the mounting matrix, if present */
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| 	ret = iio_read_mount_matrix(dev, &st->orientation);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/* Fetch and turn on regulators */
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| 	st->regs[0].supply = kxsd9_reg_vdd;
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| 	st->regs[1].supply = kxsd9_reg_iovdd;
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| 	ret = devm_regulator_bulk_get(dev,
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| 				      ARRAY_SIZE(st->regs),
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| 				      st->regs);
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| 	if (ret) {
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| 		dev_err(dev, "Cannot get regulators\n");
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| 		return ret;
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| 	}
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| 	/* Default scaling */
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| 	st->scale = KXSD9_CTRL_C_FS_2G;
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| 
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| 	kxsd9_power_up(st);
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| 
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| 	ret = iio_triggered_buffer_setup(indio_dev,
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| 					 iio_pollfunc_store_time,
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| 					 kxsd9_trigger_handler,
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| 					 &kxsd9_buffer_setup_ops);
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| 	if (ret) {
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| 		dev_err(dev, "triggered buffer setup failed\n");
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| 		goto err_power_down;
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| 	}
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| 
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| 	ret = iio_device_register(indio_dev);
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| 	if (ret)
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| 		goto err_cleanup_buffer;
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| 
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| 	dev_set_drvdata(dev, indio_dev);
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| 
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| 	/* Enable runtime PM */
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| 	pm_runtime_get_noresume(dev);
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| 	pm_runtime_set_active(dev);
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| 	pm_runtime_enable(dev);
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| 	/*
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| 	 * Set autosuspend to two orders of magnitude larger than the
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| 	 * start-up time. 20ms start-up time means 2000ms autosuspend,
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| 	 * i.e. 2 seconds.
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| 	 */
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| 	pm_runtime_set_autosuspend_delay(dev, 2000);
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| 	pm_runtime_use_autosuspend(dev);
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| 	pm_runtime_put(dev);
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| 
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| 	return 0;
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| 
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| err_cleanup_buffer:
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| 	iio_triggered_buffer_cleanup(indio_dev);
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| err_power_down:
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| 	kxsd9_power_down(st);
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| 
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| 	return ret;
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| }
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| EXPORT_SYMBOL(kxsd9_common_probe);
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| 
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| void kxsd9_common_remove(struct device *dev)
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| {
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| 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
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| 	struct kxsd9_state *st = iio_priv(indio_dev);
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| 
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| 	iio_triggered_buffer_cleanup(indio_dev);
 | |
| 	iio_device_unregister(indio_dev);
 | |
| 	pm_runtime_get_sync(dev);
 | |
| 	pm_runtime_put_noidle(dev);
 | |
| 	pm_runtime_disable(dev);
 | |
| 	kxsd9_power_down(st);
 | |
| }
 | |
| EXPORT_SYMBOL(kxsd9_common_remove);
 | |
| 
 | |
| #ifdef CONFIG_PM
 | |
| static int kxsd9_runtime_suspend(struct device *dev)
 | |
| {
 | |
| 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 | |
| 	struct kxsd9_state *st = iio_priv(indio_dev);
 | |
| 
 | |
| 	return kxsd9_power_down(st);
 | |
| }
 | |
| 
 | |
| static int kxsd9_runtime_resume(struct device *dev)
 | |
| {
 | |
| 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 | |
| 	struct kxsd9_state *st = iio_priv(indio_dev);
 | |
| 
 | |
| 	return kxsd9_power_up(st);
 | |
| }
 | |
| #endif /* CONFIG_PM */
 | |
| 
 | |
| const struct dev_pm_ops kxsd9_dev_pm_ops = {
 | |
| 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 | |
| 				pm_runtime_force_resume)
 | |
| 	SET_RUNTIME_PM_OPS(kxsd9_runtime_suspend,
 | |
| 			   kxsd9_runtime_resume, NULL)
 | |
| };
 | |
| EXPORT_SYMBOL(kxsd9_dev_pm_ops);
 | |
| 
 | |
| MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
 | |
| MODULE_DESCRIPTION("Kionix KXSD9 driver");
 | |
| MODULE_LICENSE("GPL v2");
 |