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Message-ID: <4CAF2ED9.40209@cam.ac.uk>
Date:	Fri, 08 Oct 2010 15:46:49 +0100
From:	Jonathan Cameron <jic23@....ac.uk>
To:	Samu Onkalo <samu.p.onkalo@...ia.com>
CC:	linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org,
	alan@...rguk.ukuu.org.uk
Subject: Re: [PATCHv2 3/5] misc: Driver for APDS990X ALS and proximity sensors

On 10/08/10 14:42, Samu Onkalo wrote:
> This is a driver for Avago APDS990X combined ALS and proximity sensor.
> 
> Interface is sysfs based. The driver uses interrupts to provide new data.
> The driver supports pm_runtime and regulator frameworks.
> 
> See Documentation/misc-devices/apds990x.txt for details
Couple of nitpicks inline based on a quick read.
> 
> Signed-off-by: Samu Onkalo <samu.p.onkalo@...ia.com>
> ---
>  drivers/misc/apds990x.c      | 1303 ++++++++++++++++++++++++++++++++++++++++++
>  include/linux/i2c/apds990x.h |   58 ++
>  2 files changed, 1361 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/misc/apds990x.c
>  create mode 100644 include/linux/i2c/apds990x.h
> 
> diff --git a/drivers/misc/apds990x.c b/drivers/misc/apds990x.c
> new file mode 100644
> index 0000000..658c5c4
> --- /dev/null
> +++ b/drivers/misc/apds990x.c
> @@ -0,0 +1,1303 @@
> +/*
> + * This file is part of the APDS990x sensor driver.
> + * Chip is combined proximity and ambient light sensor.
> + *
> + * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
> + *
> + * Contact: Samu Onkalo <samu.p.onkalo@...ia.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
> + * 02110-1301 USA
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/mutex.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/delay.h>
> +#include <linux/wait.h>
> +#include <linux/slab.h>
> +#include <linux/i2c/apds990x.h>
> +
> +/* Register map */
> +#define APDS990X_ENABLE	 0x00 /* Enable of states and interrupts */
> +#define APDS990X_ATIME	 0x01 /* ALS ADC time  */
> +#define APDS990X_PTIME	 0x02 /* Proximity ADC time  */
> +#define APDS990X_WTIME	 0x03 /* Wait time  */
> +#define APDS990X_AILTL	 0x04 /* ALS interrupt low threshold low byte */
> +#define APDS990X_AILTH	 0x05 /* ALS interrupt low threshold hi byte */
> +#define APDS990X_AIHTL	 0x06 /* ALS interrupt hi threshold low byte */
> +#define APDS990X_AIHTH	 0x07 /* ALS interrupt hi threshold hi byte */
> +#define APDS990X_PILTL	 0x08 /* Proximity interrupt low threshold low byte */
> +#define APDS990X_PILTH	 0x09 /* Proximity interrupt low threshold hi byte */
> +#define APDS990X_PIHTL	 0x0a /* Proximity interrupt hi threshold low byte */
> +#define APDS990X_PIHTH	 0x0b /* Proximity interrupt hi threshold hi byte */
> +#define APDS990X_PERS	 0x0c /* Interrupt persistence filters */
> +#define APDS990X_CONFIG	 0x0d /* Configuration */
> +#define APDS990X_PPCOUNT 0x0e /* Proximity pulse count */
> +#define APDS990X_CONTROL 0x0f /* Gain control register */
> +#define APDS990X_REV	 0x11 /* Revision Number */
> +#define APDS990X_ID	 0x12 /* Device ID */
> +#define APDS990X_STATUS	 0x13 /* Device status */
> +#define APDS990X_CDATAL	 0x14 /* Clear ADC low data register */
> +#define APDS990X_CDATAH	 0x15 /* Clear ADC high data register */
> +#define APDS990X_IRDATAL 0x16 /* IR ADC low data register */
> +#define APDS990X_IRDATAH 0x17 /* IR ADC high data register */
> +#define APDS990X_PDATAL	 0x18 /* Proximity ADC low data register */
> +#define APDS990X_PDATAH	 0x19 /* Proximity ADC high data register */
> +
> +/* Control */
> +#define APDS990X_MAX_AGAIN	3
> +
> +/* Enable register */
> +#define APDS990X_EN_PIEN	(0x1 << 5)
> +#define APDS990X_EN_AIEN	(0x1 << 4)
> +#define APDS990X_EN_WEN		(0x1 << 3)
> +#define APDS990X_EN_PEN		(0x1 << 2)
> +#define APDS990X_EN_AEN		(0x1 << 1)
> +#define APDS990X_EN_PON		(0x1 << 0)
> +#define APDS990X_EN_DISABLE_ALL 0
> +
> +/* Status register */
> +#define APDS990X_ST_PINT	(0x1 << 5)
> +#define APDS990X_ST_AINT	(0x1 << 4)
> +
> +/* I2C access types */
> +#define APDS990x_CMD_TYPE_MASK	(0x03 << 5)
> +#define APDS990x_CMD_TYPE_RB	(0x00 << 5) /* Repeated byte */
> +#define APDS990x_CMD_TYPE_INC	(0x01 << 5) /* Auto increment */
> +#define APDS990x_CMD_TYPE_SPE	(0x03 << 5) /* Special function */
> +
> +#define APDS990x_ADDR_SHIFT	0
> +#define APDS990x_CMD		0x80
> +
> +/* Interrupt ack commands */
> +#define APDS990X_INT_ACK_ALS	0x6
> +#define APDS990X_INT_ACK_PS	0x5
> +#define APDS990X_INT_ACK_BOTH	0x7
> +
> +/* ptime */
> +#define APDS990X_PTIME_DEFAULT	0xff /* Recommended conversion time 2.7ms*/
> +
> +/* wtime */
> +#define APDS990X_WTIME_DEFAULT	0xee /* ~50ms wait time */
> +
> +#define APDS990X_TIME_TO_ADC	1024 /* One timetick as ADC count value */
> +
> +/* Persistence */
> +#define APDS990X_APERS_SHIFT	0
> +#define APDS990X_PPERS_SHIFT	4
> +
> +/* Supported ID:s */
> +#define APDS990X_ID_0		0x0
> +#define APDS990X_ID_4		0x4
> +#define APDS990X_ID_29		0x29
> +
> +/* pgain and pdiode settings */
> +#define APDS_PGAIN_1X	       0x0
> +#define APDS_PDIODE_IR	       0x2
> +
> +#define APDS990X_LUX_OUTPUT_SCALE 10
> +
> +/* Reverse chip factors for threshold calculation */
> +struct reverse_factors {
> +	u32 afactor;
> +	int cf1;
> +	int irf1;
> +	int cf2;
> +	int irf2;
> +};
> +
> +struct apds990x_chip {
> +	struct apds990x_platform_data	*pdata;
> +	struct i2c_client		*client;
> +	struct mutex			mutex; /* avoid parallel access */
> +	struct regulator_bulk_data	regs[2];
> +	wait_queue_head_t		wait;
> +
> +	int	prox_en;
> +	bool	prox_continuous_mode;
> +	bool	lux_wait_fresh_res;
> +
> +	/* Chip parameters */
> +	struct	apds990x_chip_factors	cf;
> +	struct	reverse_factors		rcf;
> +	u16	atime;		/* als integration time */
> +	u16	arate;		/* als reporting rate */

This is nicely set to a value but then it doesn't seem to be used so don't
bother!
> +	u16	fsm_rate;	/* state machine rotations in second */
Likewise.
> +	u16	fsm_time;	/* state machine loop time */

> +	u16	a_max_result;	/* Max possible ADC value with current atime */
> +	u8	again_meas;	/* Gain used in last measurement */
> +	u8	again_next;	/* Next calculated gain */
> +	u8	pgain;
> +	u8	pdiode;
> +	u8	pdrive;
> +	u8	lux_persistence;
> +	u8	prox_persistence;
> +
> +	u32	lux_raw;
> +	u32	lux;
> +	u16	lux_clear;
> +	u16	lux_ir;
> +	u16	lux_calib;
> +	u32	lux_thres_hi;
> +	u32	lux_thres_lo;
> +
> +	u32	prox_thres;
> +	u16	prox_data;
> +	u16	prox_calib;
> +
> +	char	chipname[10];
> +	u8	revision;
> +};
> +
> +#define APDS_CALIB_SCALER		8192
> +#define APDS_LUX_NEUTRAL_CALIB_VALUE	(1 * APDS_CALIB_SCALER)
> +#define APDS_PROX_NEUTRAL_CALIB_VALUE	(1 * APDS_CALIB_SCALER)
> +
> +#define APDS_PROX_DEF_THRES		600
> +#define APDS_PROX_HYSTERESIS		50
> +#define APDS_LUX_DEF_THRES_HI		101
> +#define APDS_LUX_DEF_THRES_LO		100
> +#define APDS_DEFAULT_PROX_PERS		1
> +
> +#define APDS_TIMEOUT			2000
> +#define APDS_STARTUP_DELAY		25000 /* us */
> +#define APDS_RANGE			65535
> +#define APDS_PROX_RANGE			1023
> +#define APDS_LUX_GAIN_LO_LIMIT		100
> +#define APDS_LUX_GAIN_LO_LIMIT_STRICT	25
> +
> +#define TIMESTEP			87 /* 2.7ms is about 87 / 32 */
> +#define TIME_STEP_SCALER		32
> +
> +#define APDS_LUX_AVERAGING_TIME		50 /* tolerates 50/60Hz ripple */
> +#define APDS_LUX_DEFAULT_RATE		200
> +
> +static const u8 again[]	= {1, 8, 16, 120}; /* ALS gain steps */
> +static const u8 ir_currents[]	= {100, 50, 25, 12}; /* IRled currents in mA */
> +
> +/* Following two tables must match i.e 10Hz rate means 1 as persistence value */
> +static const u16 arates_hz[] = {10, 5, 2, 1};
> +static const u8 apersis[] = {1, 2, 4, 5};
> +
> +/* Regulators */
> +static const char reg_vcc[] = "Vdd";
> +static const char reg_vled[] = "Vled";
> +
> +static int apds990x_read_byte(struct apds990x_chip *chip, u8 reg, u8 *data)
> +{
> +	struct i2c_client *client = chip->client;
> +	s32 ret;
> +
> +	reg &= ~APDS990x_CMD_TYPE_MASK;
> +	reg |= APDS990x_CMD | APDS990x_CMD_TYPE_RB;
> +
> +	ret = i2c_smbus_read_byte_data(client, reg);
> +	*data = ret;
> +	return (int)ret;
> +}
> +
> +static int apds990x_read_word(struct apds990x_chip *chip, u8 reg, u16 *data)
> +{
> +	struct i2c_client *client = chip->client;
> +	s32 ret;
> +
> +	reg &= ~APDS990x_CMD_TYPE_MASK;
> +	reg |= APDS990x_CMD | APDS990x_CMD_TYPE_INC;
> +
> +	ret = i2c_smbus_read_word_data(client, reg);
> +	*data = ret;
> +	return (int)ret;
> +}
> +
> +static int apds990x_write_byte(struct apds990x_chip *chip, u8 reg, u8 data)
> +{
> +	struct i2c_client *client = chip->client;
> +	s32 ret;
> +
> +	reg &= ~APDS990x_CMD_TYPE_MASK;
> +	reg |= APDS990x_CMD | APDS990x_CMD_TYPE_RB;
> +
> +	ret = i2c_smbus_write_byte_data(client, reg, data);
> +	return (int)ret;
> +}
> +
> +static int apds990x_write_word(struct apds990x_chip *chip, u8 reg, u16 data)
> +{
> +	struct i2c_client *client = chip->client;
> +	s32 ret;
> +
> +	reg &= ~APDS990x_CMD_TYPE_MASK;
> +	reg |= APDS990x_CMD | APDS990x_CMD_TYPE_INC;
> +
> +	ret = i2c_smbus_write_word_data(client, reg, data);
> +	return (int)ret;
> +}
> +
> +static int apds990x_mode_on(struct apds990x_chip *chip)
> +{
> +	/* ALS is mandatory, proximity optional */
> +	u8 reg = APDS990X_EN_AIEN | APDS990X_EN_PON | APDS990X_EN_AEN |
> +		APDS990X_EN_WEN;
> +
> +	if (chip->prox_en)
> +		reg |= APDS990X_EN_PIEN | APDS990X_EN_PEN;
> +
> +	return apds990x_write_byte(chip, APDS990X_ENABLE, reg);
> +}
> +
> +static u16 apds990x_lux_to_threshold(struct apds990x_chip *chip, u32 lux)
> +{
> +	u32 thres;
> +	u32 cpl;
> +	u32 ir;
> +
> +	if (lux == 0)
> +		return 0;
> +	else if (lux == APDS_RANGE)
> +		return APDS_RANGE;
> +
> +	/*
> +	 * Reported LUX value is a combination of the IR and CLEAR channel
> +	 * values. However, interrupt threshold is only for clear channel.
> +	 * This function approximates needed HW threshold value for a given
> +	 * LUX value in the current lightning type.
> +	 * IR level compared to visible light varies heavily depending on the
> +	 * source of the light
> +	 *
> +	 * Calculate threshold value for the next measurement period.
> +	 * Math: threshold = lux * cpl where
> +	 * cpl = atime * again / (glass_attenuation * device_factor)
> +	 * (count-per-lux)
> +	 *
> +	 * First remove calibration. Division by four is to avoid overflow
> +	 */
> +	lux = lux * (APDS_CALIB_SCALER / 4) / (chip->lux_calib / 4);
> +
> +	/* Multiplication by 64 is to increase accuracy */
> +	cpl = ((u32)chip->atime * (u32)again[chip->again_next] *
> +		APDS_PARAM_SCALE * 64) / (chip->cf.ga * chip->cf.df);
> +
> +	thres = lux * cpl / 64;
> +	/*
> +	 * Convert IR light from the latest result to match with
> +	 * new gain step. This helps to adapt with the current
> +	 * source of light.
> +	 */
> +	ir = (u32)chip->lux_ir * (u32)again[chip->again_next] /
> +		(u32)again[chip->again_meas];
> +
> +	/*
> +	 * Compensate count with IR light impact
> +	 * IAC1 > IAC2 (see apds990x_get_lux for formulas)
> +	 */
> +	if (chip->lux_clear * APDS_PARAM_SCALE >=
> +		chip->rcf.afactor * chip->lux_ir)
> +		thres = (chip->rcf.cf1 * thres + chip->rcf.irf1 * ir) /
> +			APDS_PARAM_SCALE;
> +	else
> +		thres = (chip->rcf.cf2 * thres + chip->rcf.irf2 * ir) /
> +			APDS_PARAM_SCALE;
> +
> +	if (thres >= chip->a_max_result)
> +		thres = chip->a_max_result - 1;
> +	return thres;
> +}
> +
> +static inline int apds990x_set_atime(struct apds990x_chip *chip, u32 time_ms)
> +{
> +	u8 reg_value;
> +
> +	chip->atime = time_ms;
> +	/* Formula is specified in the data sheet */
> +	reg_value = 256 - ((time_ms * TIME_STEP_SCALER) / TIMESTEP);
> +	/* Calculate max ADC value for given integration time */
> +	chip->a_max_result = (u16)(256 - reg_value) * APDS990X_TIME_TO_ADC;
> +	return apds990x_write_byte(chip, APDS990X_ATIME, reg_value);
> +}
> +
> +/* Called always with mutex locked */
> +static int apds990x_refresh_pthres(struct apds990x_chip *chip, int data)
> +{
> +	int ret, lo, hi;
> +
> +	/* If the chip is not in use, don't try to access it */
> +	if (pm_runtime_suspended(&chip->client->dev))
> +		return 0;
> +
> +	if (data < chip->prox_thres) {
> +		lo = 0;
> +		hi = chip->prox_thres;
> +	} else {
> +		lo = chip->prox_thres - APDS_PROX_HYSTERESIS;
> +		if (chip->prox_continuous_mode)
> +			hi = chip->prox_thres;
> +		else
> +			hi = APDS_RANGE;
> +	}
> +
> +	ret = apds990x_write_word(chip, APDS990X_PILTL, lo);
> +	ret |= apds990x_write_word(chip, APDS990X_PIHTL, hi);
> +	return ret;
> +}
> +
> +/* Called always with mutex locked */
> +static int apds990x_refresh_athres(struct apds990x_chip *chip)
> +{
> +	int ret;
> +	/* If the chip is not in use, don't try to access it */
> +	if (pm_runtime_suspended(&chip->client->dev))
> +		return 0;
> +
> +	ret = apds990x_write_word(chip, APDS990X_AILTL,
> +			apds990x_lux_to_threshold(chip, chip->lux_thres_lo));
> +	ret |= apds990x_write_word(chip, APDS990X_AIHTL,
> +			apds990x_lux_to_threshold(chip, chip->lux_thres_hi));
> +
> +	return ret;
> +}
> +
> +/* Called always with mutex locked */
> +static void apds990x_force_a_refresh(struct apds990x_chip *chip)
> +{
> +	/* This will force ALS interrupt after the next measurement. */
> +	apds990x_write_word(chip, APDS990X_AILTL, APDS_LUX_DEF_THRES_LO);
> +	apds990x_write_word(chip, APDS990X_AIHTL, APDS_LUX_DEF_THRES_HI);
> +}
> +
> +/* Called always with mutex locked */
> +static void apds990x_force_p_refresh(struct apds990x_chip *chip)
> +{
> +	/* This will force proximity interrupt after the next measurement. */
> +	apds990x_write_word(chip, APDS990X_PILTL, APDS_PROX_DEF_THRES - 1);
> +	apds990x_write_word(chip, APDS990X_PIHTL, APDS_PROX_DEF_THRES);
> +}
> +
> +/* Called always with mutex locked */
> +static int apds990x_calc_again(struct apds990x_chip *chip)
> +{
> +	int curr_again = chip->again_meas;
> +	int next_again = chip->again_meas;
> +	int ret = 0;
> +
> +	/* Calculate suitable als gain */
> +	if (chip->lux_clear == chip->a_max_result)
> +		next_again -= 2; /* ALS saturated. Decrease gain by 2 steps */
> +	else if (chip->lux_clear > chip->a_max_result / 2)
> +		next_again--;
> +	else if (chip->lux_clear < APDS_LUX_GAIN_LO_LIMIT_STRICT)
> +		next_again += 2; /* Too dark. Increase gain by 2 steps */
> +	else if (chip->lux_clear < APDS_LUX_GAIN_LO_LIMIT)
> +		next_again++;
> +
> +	/* Limit gain to available range */
> +	if (next_again < 0)
> +		next_again = 0;
> +	else if (next_again > APDS990X_MAX_AGAIN)
> +		next_again = APDS990X_MAX_AGAIN;
> +
> +	/* Let's check can we trust the measured result */
Excess brackets.  Be it disguised by the lines of comments.
> +	if (chip->lux_clear == chip->a_max_result) {
> +		/* Result can be totally garbage due to saturation */
> +		ret = -ERANGE;
> +	} else if (next_again != curr_again &&
> +		   chip->lux_clear < APDS_LUX_GAIN_LO_LIMIT_STRICT) {
> +		/*
> +		 * Gain is changed and measurement result is very small.
> +		 * Result can be totally garbage due to underflow
> +		 */
> +		ret = -ERANGE;
> +	}
> +
> +	chip->again_next = next_again;
> +	apds990x_write_byte(chip, APDS990X_CONTROL,
> +			(chip->pdrive << 6) |
> +			(chip->pdiode << 4) |
> +			(chip->pgain << 2) |
> +			(chip->again_next << 0));
> +
> +	/*
> +	 * Error means bad result -> re-measurement is needed. The forced
> +	 * refresh uses fastest possible persistence setting to get result
> +	 * as soon as possible.
> +	 */
> +	if (ret < 0)
> +		apds990x_force_a_refresh(chip);
> +	else
> +		apds990x_refresh_athres(chip);
> +
> +	return ret;
> +}
> +
> +/* Called always with mutex locked */
> +static int apds990x_get_lux(struct apds990x_chip *chip, int clear, int ir)
> +{
> +	int iac, iac1, iac2; /* IR adjusted counts */
> +	u32 lpc; /* Lux per count */
> +
> +	/* Formulas:
> +	 * iac1 = CF1 * CLEAR_CH - IRF1 * IR_CH
> +	 * iac2 = CF2 * CLEAR_CH - IRF2 * IR_CH
> +	 */
> +	iac1 = (chip->cf.cf1 * clear - chip->cf.irf1 * ir) / APDS_PARAM_SCALE;
> +	iac2 = (chip->cf.cf2 * clear - chip->cf.irf2 * ir) / APDS_PARAM_SCALE;
> +
> +	iac = max(iac1, iac2);
> +	iac = max(iac, 0);
> +
> +	lpc = APDS990X_LUX_OUTPUT_SCALE * (chip->cf.df * chip->cf.ga) /
> +		(u32)(again[chip->again_meas] * (u32)chip->atime);
> +
> +	return (iac * lpc) / APDS_PARAM_SCALE;
> +}
> +
> +static int apds990x_ack_int(struct apds990x_chip *chip, u8 mode)
> +{
> +	struct i2c_client *client = chip->client;
> +	s32 ret;
> +	u8 reg = APDS990x_CMD | APDS990x_CMD_TYPE_SPE;
> +
> +	switch (mode & (APDS990X_ST_AINT | APDS990X_ST_PINT)) {
> +	case APDS990X_ST_AINT:
> +		reg |= APDS990X_INT_ACK_ALS;
> +		break;
> +	case APDS990X_ST_PINT:
> +		reg |= APDS990X_INT_ACK_PS;
> +		break;
> +	default:
> +		reg |= APDS990X_INT_ACK_BOTH;
> +		break;
> +	}
> +
> +	ret = i2c_smbus_read_byte_data(client, reg);
> +	return (int)ret;
> +}
> +
> +static irqreturn_t apds990x_irq(int irq, void *data)
> +{
> +	struct apds990x_chip *chip = data;
> +	u8 status;
> +
> +	apds990x_read_byte(chip, APDS990X_STATUS, &status);
> +	apds990x_ack_int(chip, status);
> +
> +	mutex_lock(&chip->mutex);
> +	if (!pm_runtime_suspended(&chip->client->dev)) {
> +		if (status & APDS990X_ST_AINT) {
> +			apds990x_read_word(chip, APDS990X_CDATAL,
> +					&chip->lux_clear);
> +			apds990x_read_word(chip, APDS990X_IRDATAL,
> +					&chip->lux_ir);
> +			/* Store used gain for calculations */
> +			chip->again_meas = chip->again_next;
> +
> +			chip->lux_raw = apds990x_get_lux(chip,
> +							chip->lux_clear,
> +							chip->lux_ir);
> +
> +			if (apds990x_calc_again(chip) == 0) {
> +				/* Result is valid */
> +				chip->lux = chip->lux_raw;
> +				chip->lux_wait_fresh_res = false;
> +				wake_up(&chip->wait);
> +				sysfs_notify(&chip->client->dev.kobj,
> +					NULL, "lux0_input");
> +			}
> +		}
> +
> +		if (status & APDS990X_ST_PINT)
> +			if (chip->prox_en) {
if ((status & APDS990X_ST_PINT) && chip->prox_en) perhaps?
Gives you a bit more space for longer lines in here if nothing else.

> +				u16 clr_ch;
> +
> +				apds990x_read_word(chip, APDS990X_CDATAL,
> +						&clr_ch);
> +				/*
> +				 * If ALS channel is saturated at min gain,
> +				 * proximity gives false posivite values.
> +				 * Just ignore them.
> +				 */
> +				if (chip->again_meas == 0 &&
> +				    clr_ch == chip->a_max_result) {
> +					chip->prox_data = 0;
> +				} else {
> +					apds990x_read_word(chip,
> +							APDS990X_PDATAL,
> +							&chip->prox_data);
> +				}
> +				apds990x_refresh_pthres(chip, chip->prox_data);
> +				if (chip->prox_data < chip->prox_thres)
> +					chip->prox_data = 0;
> +				else if (!chip->prox_continuous_mode)
> +					chip->prox_data = APDS_PROX_RANGE;
> +				sysfs_notify(&chip->client->dev.kobj,
> +					NULL, "prox0_raw");
> +			}
> +	}
> +	mutex_unlock(&chip->mutex);
> +	return IRQ_HANDLED;
> +}
> +
> +static int apds990x_configure(struct apds990x_chip *chip)
> +{
> +	/* It is recommended to use disabled mode during these operations */
> +	apds990x_write_byte(chip, APDS990X_ENABLE, APDS990X_EN_DISABLE_ALL);
> +
> +	/* conversion and wait times for different state machince states */
> +	apds990x_write_byte(chip, APDS990X_PTIME, APDS990X_PTIME_DEFAULT);
> +	apds990x_write_byte(chip, APDS990X_WTIME, APDS990X_WTIME_DEFAULT);
> +	apds990x_set_atime(chip, APDS_LUX_AVERAGING_TIME);
> +
> +	apds990x_write_byte(chip, APDS990X_CONFIG, 0);
> +
> +	/*
> +	 * Total time for one FSM round without proximity.
> +	 * One bit in wait is about 2.7 ms = 27 / 10.
> +	 * rate = 1000 ms / fsm loop time in ms.
> +	 */
> +	chip->fsm_time = APDS_LUX_AVERAGING_TIME +
> +				(256 - APDS990X_WTIME_DEFAULT) * 27 / 10;
> +	chip->fsm_rate = 1000 / chip->fsm_time;
> +
> +	/* Persistence levels */
> +	apds990x_write_byte(chip, APDS990X_PERS,
> +			(chip->lux_persistence << APDS990X_APERS_SHIFT) |
> +			(chip->prox_persistence << APDS990X_PPERS_SHIFT));
> +
> +	apds990x_write_byte(chip, APDS990X_PPCOUNT, chip->pdata->ppcount);
> +
> +	/* Start with relatively small gain */
> +	chip->again_meas = 1;
> +	chip->again_next = 1;
> +	apds990x_write_byte(chip, APDS990X_CONTROL,
> +			(chip->pdrive << 6) |
> +			(chip->pdiode << 4) |
> +			(chip->pgain << 2) |
> +			(chip->again_next << 0));
> +	return 0;
> +}
> +
> +static int apds990x_detect(struct apds990x_chip *chip)
> +{
> +	struct i2c_client *client = chip->client;
> +	int ret;
> +	u8 id;
> +
> +	ret = apds990x_read_byte(chip, APDS990X_ID, &id);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "ID read failed\n");
> +		return ret;
> +	}
> +
> +	ret = apds990x_read_byte(chip, APDS990X_REV, &chip->revision);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "REV read failed\n");
> +		return ret;
> +	}
> +
> +	switch (id) {
> +	case APDS990X_ID_0:
> +	case APDS990X_ID_4:
> +	case APDS990X_ID_29:
> +		snprintf(chip->chipname, sizeof(chip->chipname), "APDS-990x");
> +		break;
> +	default:
> +		ret = -ENODEV;
> +		break;
> +	}
> +	return ret;
> +}
> +
> +static int apds990x_chip_on(struct apds990x_chip *chip)
> +{
> +	int err	 = regulator_bulk_enable(ARRAY_SIZE(chip->regs),
> +					chip->regs);
> +	if (err < 0)
> +		return err;
> +
> +	usleep_range(APDS_STARTUP_DELAY, 2 * APDS_STARTUP_DELAY);
> +
> +	/* Refresh all configs in case of regulators were off */
> +	apds990x_configure(chip);
> +	apds990x_mode_on(chip);
> +	return 0;
> +}
> +
> +static int apds990x_chip_off(struct apds990x_chip *chip)
> +{
> +	apds990x_write_byte(chip, APDS990X_ENABLE, APDS990X_EN_DISABLE_ALL);
> +	regulator_bulk_disable(ARRAY_SIZE(chip->regs), chip->regs);
> +	return 0;
> +}
> +
> +static ssize_t apds990x_lux_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip = dev_get_drvdata(dev);
> +	ssize_t ret;
> +	u32 result;
> +	long timeout;
> +
> +	if (pm_runtime_suspended(dev))
> +		return -EIO;
> +
> +	timeout = wait_event_interruptible_timeout(chip->wait,
> +						!chip->lux_wait_fresh_res,
> +						msecs_to_jiffies(APDS_TIMEOUT));
> +	if (!timeout)
> +		return -EIO;
> +
> +	mutex_lock(&chip->mutex);
> +	result = (chip->lux * chip->lux_calib) / APDS_CALIB_SCALER;
> +	if (result > (APDS_RANGE * APDS990X_LUX_OUTPUT_SCALE))
> +		result = APDS_RANGE * APDS990X_LUX_OUTPUT_SCALE;
> +
> +	ret = snprintf(buf, PAGE_SIZE, "%d.%d\n",
> +		result / APDS990X_LUX_OUTPUT_SCALE,
> +		result % APDS990X_LUX_OUTPUT_SCALE);
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +}
> +
> +static DEVICE_ATTR(lux0_input, S_IRUGO, apds990x_lux_show, NULL);
> +
> +static ssize_t apds990x_lux_range_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	return snprintf(buf, PAGE_SIZE, "%u\n", APDS_RANGE);
> +}
> +
> +static DEVICE_ATTR(lux0_sensor_range, S_IRUGO, apds990x_lux_range_show, NULL);
> +
> +static ssize_t apds990x_lux_calib_format_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	return snprintf(buf, PAGE_SIZE, "%u\n", APDS_CALIB_SCALER);
> +}
Some nice paranoid length parameters... not really necessary but
don't do much harm.
> +
> +static DEVICE_ATTR(lux0_calibscale_default, S_IRUGO,
> +		apds990x_lux_calib_format_show, NULL);
> +
> +static ssize_t apds990x_lux_calib_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip = dev_get_drvdata(dev);
> +
> +	return snprintf(buf, PAGE_SIZE, "%u\n", chip->lux_calib);
> +}
> +
> +static ssize_t apds990x_lux_calib_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip = dev_get_drvdata(dev);
> +	unsigned long value;
> +
> +	if (strict_strtoul(buf, 0, &value))
> +		return -EINVAL;
> +
> +	if (chip->lux_calib > APDS_RANGE)
> +		return -EINVAL;
> +
> +	chip->lux_calib = value;
> +
> +	return len;
> +}
> +
> +static DEVICE_ATTR(lux0_calibscale, S_IRUGO | S_IWUSR, apds990x_lux_calib_show,
> +		apds990x_lux_calib_store);
> +
> +static ssize_t apds990x_rate_avail(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	int i;
> +	int pos = 0;
> +	for (i = 0; i < ARRAY_SIZE(arates_hz); i++)
> +		pos += sprintf(buf + pos, "%d ", arates_hz[i]);
> +	sprintf(buf + pos - 1, "\n");
> +	return pos;
> +}
> +
> +static ssize_t apds990x_rate_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%d\n", chip->arate);
> +}
> +
> +static int apds990x_set_arate(struct apds990x_chip *chip, int rate)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(arates_hz); i++)
> +		if (rate >= arates_hz[i])
> +			break;
> +
> +	if (i == ARRAY_SIZE(arates_hz))
> +		return -EINVAL;
> +
> +	/* Pick up corresponding persistence value */
> +	chip->lux_persistence = apersis[i];
> +	chip->arate = arates_hz[i];
> +
> +	/* If the chip is not in use, don't try to access it */
> +	if (pm_runtime_suspended(&chip->client->dev))
> +		return 0;
> +
> +	/* Persistence levels */
> +	return apds990x_write_byte(chip, APDS990X_PERS,
> +			(chip->lux_persistence << APDS990X_APERS_SHIFT) |
> +			(chip->prox_persistence << APDS990X_PPERS_SHIFT));
> +}
> +
> +static ssize_t apds990x_rate_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	unsigned long value;
> +	int ret;
> +
> +	if (strict_strtoul(buf, 0, &value))
> +		return -EINVAL;
> +
> +	mutex_lock(&chip->mutex);
> +	ret = apds990x_set_arate(chip, value);
> +	mutex_unlock(&chip->mutex);
> +
> +	if (ret < 0)
> +		return ret;
> +	return len;
> +}
> +
> +static DEVICE_ATTR(lux0_rate_avail, S_IRUGO, apds990x_rate_avail, NULL);
> +
> +static DEVICE_ATTR(lux0_rate, S_IRUGO | S_IWUSR, apds990x_rate_show,
> +						 apds990x_rate_store);
> +
> +static ssize_t apds990x_prox_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	ssize_t ret;
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	if (pm_runtime_suspended(dev) || !chip->prox_en)
> +		return -EIO;
> +
> +	mutex_lock(&chip->mutex);
> +	ret = snprintf(buf, PAGE_SIZE, "%d\n", chip->prox_data);
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +}
> +
> +static DEVICE_ATTR(prox0_raw, S_IRUGO, apds990x_prox_show, NULL);
> +
> +static ssize_t apds990x_prox_range_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	return snprintf(buf, PAGE_SIZE, "%u\n", APDS_PROX_RANGE);
> +}
> +
> +static DEVICE_ATTR(prox0_sensor_range, S_IRUGO, apds990x_prox_range_show, NULL);
> +
> +static ssize_t apds990x_prox_enable_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%d\n", chip->prox_en);
> +}
> +
> +static ssize_t apds990x_prox_enable_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	unsigned long value;
> +
> +	if (strict_strtoul(buf, 0, &value))
> +		return -EINVAL;
> +
> +	mutex_lock(&chip->mutex);
> +	if (value) {
> +		chip->prox_en++;

Perhaps use else if and scrap the excess brackets.
> +	} else {
> +		if (chip->prox_en > 0)
> +			chip->prox_en--;
> +	}
> +
> +	if (!pm_runtime_suspended(dev))
> +		apds990x_mode_on(chip);
> +	mutex_unlock(&chip->mutex);
> +	return len;
> +}
> +
> +static DEVICE_ATTR(prox0_raw_en, S_IRUGO | S_IWUSR, apds990x_prox_enable_show,
> +						   apds990x_prox_enable_store);
> +
> +static const char reporting_modes[][9] = {"trigger", "periodic"};
> +
> +static ssize_t apds990x_prox_reporting_mode_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%s\n",
> +		reporting_modes[!!chip->prox_continuous_mode]);
> +}
> +
> +static ssize_t apds990x_prox_reporting_mode_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +
> +	if (sysfs_streq(buf, reporting_modes[0]))
> +		chip->prox_continuous_mode = 0;
> +	else if (sysfs_streq(buf, reporting_modes[1]))
> +		chip->prox_continuous_mode = 1;
> +	else
> +		return -EINVAL;
> +	return len;
> +}
> +
> +static DEVICE_ATTR(prox0_reporting_mode, S_IRUGO | S_IWUSR,
> +		apds990x_prox_reporting_mode_show,
> +		apds990x_prox_reporting_mode_store);
> +
> +static ssize_t apds990x_prox_reporting_avail_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	return sprintf(buf, "%s %s\n", reporting_modes[0], reporting_modes[1]);
> +}
> +
> +static DEVICE_ATTR(prox0_reporting_mode_avail, S_IRUGO | S_IWUSR,
> +		apds990x_prox_reporting_avail_show, NULL);
> +
> +
> +static ssize_t apds990x_lux_thresh_above_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%d\n", chip->lux_thres_hi);
> +}
> +
> +static ssize_t apds990x_lux_thresh_below_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%d\n", chip->lux_thres_lo);
> +}
> +
> +static ssize_t apds990x_set_lux_thresh(struct apds990x_chip *chip, u32 *target,
> +				const char *buf)
> +{
> +	int ret = 0;
> +	unsigned long thresh;
> +
> +	if (strict_strtoul(buf, 0, &thresh))
> +		return -EINVAL;
> +
> +	if (thresh > APDS_RANGE)
> +		return -EINVAL;
> +
> +	mutex_lock(&chip->mutex);
> +	*target = thresh;
> +	/*
> +	 * Don't update values in HW if we are still waiting for
> +	 * first interrupt to come after device handle open call.
> +	 */
> +	if (!chip->lux_wait_fresh_res)
> +		apds990x_refresh_athres(chip);
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +
> +}
> +
> +static ssize_t apds990x_lux_thresh_above_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	int ret = apds990x_set_lux_thresh(chip, &chip->lux_thres_hi, buf);
> +	if (ret < 0)
> +		return ret;
> +	return len;
> +}
> +
> +static ssize_t apds990x_lux_thresh_below_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	int ret = apds990x_set_lux_thresh(chip, &chip->lux_thres_lo, buf);
> +	if (ret < 0)
> +		return ret;
> +	return len;
> +}
> +
> +static DEVICE_ATTR(lux0_thresh_above_value, S_IRUGO | S_IWUSR,
> +		apds990x_lux_thresh_above_show,
> +		apds990x_lux_thresh_above_store);
> +
> +static DEVICE_ATTR(lux0_thresh_below_value, S_IRUGO | S_IWUSR,
> +		apds990x_lux_thresh_below_show,
> +		apds990x_lux_thresh_below_store);
> +
> +static ssize_t apds990x_prox_threshold_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%d\n", chip->prox_thres);
> +}
> +
> +static ssize_t apds990x_prox_threshold_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	unsigned long value;
> +
> +	if (strict_strtoul(buf, 0, &value))
> +		return -EINVAL;
> +
> +	if ((value > APDS_RANGE) || (value == 0) ||
> +		(value < APDS_PROX_HYSTERESIS))
> +		return -EINVAL;
> +
> +	mutex_lock(&chip->mutex);
> +	chip->prox_thres = value;
> +
> +	apds990x_force_p_refresh(chip);
> +	mutex_unlock(&chip->mutex);
> +	return len;
> +}
> +
> +static DEVICE_ATTR(prox0_thresh_above_value, S_IRUGO | S_IWUSR,
> +		apds990x_prox_threshold_show,
> +		apds990x_prox_threshold_store);
> +
> +static ssize_t apds990x_power_state_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	return sprintf(buf, "%d\n", !pm_runtime_suspended(dev));
> +	return 0;
> +}
> +
> +static ssize_t apds990x_power_state_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t len)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	unsigned long value;
> +
> +	if (strict_strtoul(buf, 0, &value))
> +		return -EINVAL;
> +	if (value) {
> +		pm_runtime_get_sync(dev);
> +		mutex_lock(&chip->mutex);
> +		chip->lux_wait_fresh_res = true;
> +		apds990x_force_a_refresh(chip);
> +		apds990x_force_p_refresh(chip);
> +		mutex_unlock(&chip->mutex);
> +	} else {
> +		if (!pm_runtime_suspended(dev))
> +			pm_runtime_put(dev);
> +	}
> +	return len;
> +}
> +
> +static DEVICE_ATTR(power_state, S_IRUGO | S_IWUSR,
> +		apds990x_power_state_show,
> +		apds990x_power_state_store);
> +
> +static ssize_t apds990x_chip_id_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct apds990x_chip *chip =  dev_get_drvdata(dev);
> +	return sprintf(buf, "%s %d\n", chip->chipname, chip->revision);
> +}
> +
> +static DEVICE_ATTR(chip_id, S_IRUGO, apds990x_chip_id_show, NULL);
> +
> +static struct attribute *sysfs_attrs_ctrl[] = {
> +	&dev_attr_lux0_calibscale.attr,
> +	&dev_attr_lux0_calibscale_default.attr,
> +	&dev_attr_lux0_input.attr,
> +	&dev_attr_lux0_sensor_range.attr,
> +	&dev_attr_lux0_rate.attr,
> +	&dev_attr_lux0_rate_avail.attr,
> +	&dev_attr_lux0_thresh_above_value.attr,
> +	&dev_attr_lux0_thresh_below_value.attr,
> +	&dev_attr_prox0_raw_en.attr,
> +	&dev_attr_prox0_raw.attr,
> +	&dev_attr_prox0_sensor_range.attr,
> +	&dev_attr_prox0_thresh_above_value.attr,
> +	&dev_attr_prox0_reporting_mode.attr,
> +	&dev_attr_prox0_reporting_mode_avail.attr,
> +	&dev_attr_chip_id.attr,
> +	&dev_attr_power_state.attr,
> +	NULL
> +};
> +
> +static struct attribute_group apds990x_attribute_group[] = {
> +	{.attrs = sysfs_attrs_ctrl },
> +};
> +
> +static int __devinit apds990x_probe(struct i2c_client *client,
> +				const struct i2c_device_id *id)
> +{
> +	struct apds990x_chip *chip;
> +	int err;
> +
> +	chip = kzalloc(sizeof *chip, GFP_KERNEL);
> +	if (!chip)
> +		return -ENOMEM;
> +
> +	i2c_set_clientdata(client, chip);
> +	chip->client  = client;
> +
> +	init_waitqueue_head(&chip->wait);
> +	mutex_init(&chip->mutex);
> +	chip->pdata	= client->dev.platform_data;
> +
> +	if (chip->pdata == NULL) {
> +		dev_err(&client->dev, "platform data is mandatory\n");
> +		err = -EINVAL;
> +		goto fail1;
> +	}
> +
> +	if (chip->pdata->cf.ga == 0) {
> +		/* set uncovered sensor default parameters */
> +		chip->cf.ga = 1966; /* 0.48 * APDS_PARAM_SCALE */
> +		chip->cf.cf1 = 4096; /* 1.00 * APDS_PARAM_SCALE */
> +		chip->cf.irf1 = 9134; /* 2.23 * APDS_PARAM_SCALE */
> +		chip->cf.cf2 = 2867; /* 0.70 * APDS_PARAM_SCALE */
> +		chip->cf.irf2 = 5816; /* 1.42 * APDS_PARAM_SCALE */
> +		chip->cf.df = 52;
> +	} else {
> +		chip->cf = chip->pdata->cf;
> +	}
> +
> +	/* precalculate inverse chip factors for threshold control */
> +	chip->rcf.afactor =
> +		(chip->cf.irf1 - chip->cf.irf2) * APDS_PARAM_SCALE /
> +		(chip->cf.cf1 - chip->cf.cf2);
> +	chip->rcf.cf1 = APDS_PARAM_SCALE * APDS_PARAM_SCALE /
> +		chip->cf.cf1;
> +	chip->rcf.irf1 = chip->cf.irf1 * APDS_PARAM_SCALE /
> +		chip->cf.cf1;
> +	chip->rcf.cf2 = APDS_PARAM_SCALE * APDS_PARAM_SCALE /
> +		chip->cf.cf2;
> +	chip->rcf.irf2 = chip->cf.irf2 * APDS_PARAM_SCALE /
> +		chip->cf.cf2;
> +
> +	/* Set something to start with */
> +	chip->lux_thres_hi = APDS_LUX_DEF_THRES_HI;
> +	chip->lux_thres_lo = APDS_LUX_DEF_THRES_LO;
> +	chip->lux_calib = APDS_LUX_NEUTRAL_CALIB_VALUE;
> +
> +	chip->prox_thres = APDS_PROX_DEF_THRES;
> +	chip->pdrive = chip->pdata->pdrive;
> +	chip->pdiode = APDS_PDIODE_IR;
> +	chip->pgain = APDS_PGAIN_1X;
> +	chip->prox_calib = APDS_PROX_NEUTRAL_CALIB_VALUE;
> +	chip->prox_persistence = APDS_DEFAULT_PROX_PERS;
> +	chip->prox_continuous_mode = false;
> +
> +	chip->regs[0].supply = reg_vcc;
> +	chip->regs[1].supply = reg_vled;
> +
> +	err = regulator_bulk_get(&client->dev,
> +				 ARRAY_SIZE(chip->regs), chip->regs);
> +	if (err < 0) {
> +		dev_err(&client->dev, "Cannot get regulators\n");
> +		goto fail1;
> +	}
> +
> +	err = regulator_bulk_enable(ARRAY_SIZE(chip->regs), chip->regs);
> +	if (err < 0) {
> +		dev_err(&client->dev, "Cannot enable regulators\n");
> +		goto fail2;
> +	}
> +
> +	usleep_range(APDS_STARTUP_DELAY, 2 * APDS_STARTUP_DELAY);
> +
> +	err = apds990x_detect(chip);
> +	if (err < 0) {
> +		dev_err(&client->dev, "APDS990X not found\n");
> +		goto fail3;
> +	}
> +
> +	pm_runtime_set_active(&client->dev);
> +
> +	apds990x_configure(chip);
> +	apds990x_set_arate(chip, APDS_LUX_DEFAULT_RATE);
> +	apds990x_mode_on(chip);
> +
> +	pm_runtime_enable(&client->dev);
> +
> +	if (chip->pdata->setup_resources) {
> +		err = chip->pdata->setup_resources();
> +		if (err) {
> +			err = -EINVAL;
> +			goto fail3;
> +		}
> +	}
> +
> +	err = sysfs_create_group(&chip->client->dev.kobj,
> +				apds990x_attribute_group);
> +	if (err < 0) {
> +		dev_err(&chip->client->dev, "Sysfs registration failed\n");
> +		goto fail4;
> +	}
> +
> +	err = request_threaded_irq(client->irq, NULL,
> +				apds990x_irq,
> +				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_LOW |
> +				IRQF_ONESHOT,
> +				"apds990x", chip);
> +	if (err) {
> +		dev_err(&client->dev, "could not get IRQ %d\n",
> +			client->irq);
> +		goto fail5;
> +	}
> +	return err;
> +fail5:
> +	sysfs_remove_group(&chip->client->dev.kobj,
> +			&apds990x_attribute_group[0]);
> +fail4:
> +	if (chip->pdata && chip->pdata->release_resources)
> +		chip->pdata->release_resources();
> +fail3:
> +	regulator_bulk_disable(ARRAY_SIZE(chip->regs), chip->regs);
> +fail2:
> +	regulator_bulk_free(ARRAY_SIZE(chip->regs), chip->regs);
> +fail1:
> +	kfree(chip);
> +	return err;
> +}
> +
> +static int __devexit apds990x_remove(struct i2c_client *client)
> +{
> +	struct apds990x_chip *chip = i2c_get_clientdata(client);
> +
> +	free_irq(client->irq, chip);
> +	sysfs_remove_group(&chip->client->dev.kobj,
> +			apds990x_attribute_group);
> +
> +	if (chip->pdata && chip->pdata->release_resources)
> +		chip->pdata->release_resources();
> +
> +	if (!pm_runtime_suspended(&client->dev))
> +		apds990x_chip_off(chip);
> +
> +	regulator_bulk_free(ARRAY_SIZE(chip->regs), chip->regs);
> +
> +	kfree(chip);
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int apds990x_suspend(struct device *dev)
> +{
> +	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> +	struct apds990x_chip *chip = i2c_get_clientdata(client);
> +
> +	apds990x_chip_off(chip);
> +	return 0;
> +}
> +
> +static int apds990x_resume(struct device *dev)
> +{
> +	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> +	struct apds990x_chip *chip = i2c_get_clientdata(client);
> +
> +	/*
> +	 * If we were enabled at suspend time, it is expected
> +	 * everything works nice and smoothly. Chip_on is enough
> +	 */
> +	apds990x_chip_on(chip);
> +
> +	return 0;
> +}
> +#else
> +#define apds990x_suspend  NULL
> +#define apds990x_resume	  NULL
> +#define apds990x_shutdown NULL
> +#endif
> +
> +#ifdef CONFIG_PM_RUNTIME
> +static int apds990x_runtime_suspend(struct device *dev)
> +{
> +	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> +	struct apds990x_chip *chip = i2c_get_clientdata(client);
> +
> +	apds990x_chip_off(chip);
> +	return 0;
> +}
> +
> +static int apds990x_runtime_resume(struct device *dev)
> +{
> +	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
> +	struct apds990x_chip *chip = i2c_get_clientdata(client);
> +
> +	apds990x_chip_on(chip);
> +	return 0;
> +}
> +
> +#endif
> +
> +static const struct i2c_device_id apds990x_id[] = {
> +	{"apds990x", 0 },
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, apds990x_id);
> +
> +static const struct dev_pm_ops apds990x_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(apds990x_suspend, apds990x_resume)
> +	SET_RUNTIME_PM_OPS(apds990x_runtime_suspend,
> +			apds990x_runtime_resume,
> +			NULL)
> +};
> +
> +static struct i2c_driver apds990x_driver = {
> +	.driver	 = {
> +		.name	= "apds990x",
> +		.owner	= THIS_MODULE,
> +		.pm	= &apds990x_pm_ops,
> +	},
> +	.probe	  = apds990x_probe,
> +	.remove	  = __devexit_p(apds990x_remove),
> +	.id_table = apds990x_id,
> +};
> +
> +static int __init apds990x_init(void)
> +{
> +	return i2c_add_driver(&apds990x_driver);
> +}
> +
> +static void __exit apds990x_exit(void)
> +{
> +	i2c_del_driver(&apds990x_driver);
> +}
> +
> +MODULE_DESCRIPTION("APDS990X combined ALS and proximity sensor");
> +MODULE_AUTHOR("Samu Onkalo, Nokia Corporation");
> +MODULE_LICENSE("GPL v2");
> +
> +module_init(apds990x_init);
> +module_exit(apds990x_exit);
> diff --git a/include/linux/i2c/apds990x.h b/include/linux/i2c/apds990x.h
> new file mode 100644
> index 0000000..7d521e3
> --- /dev/null
> +++ b/include/linux/i2c/apds990x.h
> @@ -0,0 +1,58 @@
> +/*
> + * This file is part of the APDS990x sensor driver.
> + * Chip is combined proximity and ambient light sensor.
> + *
> + * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
> + *
> + * Contact: Samu Onkalo <samu.p.onkalo@...ia.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
> + * 02110-1301 USA
> + *
> + */
> +
> +#ifndef __APDS990X_H__
> +#define __APDS990X_H__
> +
> +
> +#define APDS_IRLED_CURR_12mA	0x3
> +#define APDS_IRLED_CURR_25mA	0x2
> +#define APDS_IRLED_CURR_50mA	0x1
> +#define APDS_IRLED_CURR_100mA	0x0
> +
> +/*
> + * Structure for tuning ALS calculation to match with environment.
> + * There depends on the material above the sensor and the sensor
> + * itself. If the GA is zero, driver will use uncovered sensor default values
> + * format: decimal value * APDS_PARAM_SCALE
> + */
> +#define APDS_PARAM_SCALE 4096
> +struct apds990x_chip_factors {
> +	int ga;		/* Glass attenuation */
> +	int cf1;	/* Clear channel factor 1 */
> +	int irf1;	/* Ir channel factor 1 */
> +	int cf2;	/* Clear channel factor 2 */
> +	int irf2;	/* Ir channel factor 2 */
> +	int df;		/* Device factor. Decimal number */
> +};
> +
> +struct apds990x_platform_data {
> +	struct apds990x_chip_factors cf;
> +	u8     pdrive;
> +	u8     ppcount;
> +	int    (*setup_resources)(void);
> +	int    (*release_resources)(void);
> +};
> +
> +#endif

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