cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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mlx90632.c (29532B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * mlx90632.c - Melexis MLX90632 contactless IR temperature sensor
      4 *
      5 * Copyright (c) 2017 Melexis <cmo@melexis.com>
      6 *
      7 * Driver for the Melexis MLX90632 I2C 16-bit IR thermopile sensor
      8 */
      9#include <linux/delay.h>
     10#include <linux/err.h>
     11#include <linux/gpio/consumer.h>
     12#include <linux/i2c.h>
     13#include <linux/iopoll.h>
     14#include <linux/kernel.h>
     15#include <linux/limits.h>
     16#include <linux/mod_devicetable.h>
     17#include <linux/module.h>
     18#include <linux/math64.h>
     19#include <linux/pm_runtime.h>
     20#include <linux/regmap.h>
     21
     22#include <linux/iio/iio.h>
     23#include <linux/iio/sysfs.h>
     24
     25/* Memory sections addresses */
     26#define MLX90632_ADDR_RAM	0x4000 /* Start address of ram */
     27#define MLX90632_ADDR_EEPROM	0x2480 /* Start address of user eeprom */
     28
     29/* EEPROM addresses - used at startup */
     30#define MLX90632_EE_CTRL	0x24d4 /* Control register initial value */
     31#define MLX90632_EE_I2C_ADDR	0x24d5 /* I2C address register initial value */
     32#define MLX90632_EE_VERSION	0x240b /* EEPROM version reg address */
     33#define MLX90632_EE_P_R		0x240c /* P_R calibration register 32bit */
     34#define MLX90632_EE_P_G		0x240e /* P_G calibration register 32bit */
     35#define MLX90632_EE_P_T		0x2410 /* P_T calibration register 32bit */
     36#define MLX90632_EE_P_O		0x2412 /* P_O calibration register 32bit */
     37#define MLX90632_EE_Aa		0x2414 /* Aa calibration register 32bit */
     38#define MLX90632_EE_Ab		0x2416 /* Ab calibration register 32bit */
     39#define MLX90632_EE_Ba		0x2418 /* Ba calibration register 32bit */
     40#define MLX90632_EE_Bb		0x241a /* Bb calibration register 32bit */
     41#define MLX90632_EE_Ca		0x241c /* Ca calibration register 32bit */
     42#define MLX90632_EE_Cb		0x241e /* Cb calibration register 32bit */
     43#define MLX90632_EE_Da		0x2420 /* Da calibration register 32bit */
     44#define MLX90632_EE_Db		0x2422 /* Db calibration register 32bit */
     45#define MLX90632_EE_Ea		0x2424 /* Ea calibration register 32bit */
     46#define MLX90632_EE_Eb		0x2426 /* Eb calibration register 32bit */
     47#define MLX90632_EE_Fa		0x2428 /* Fa calibration register 32bit */
     48#define MLX90632_EE_Fb		0x242a /* Fb calibration register 32bit */
     49#define MLX90632_EE_Ga		0x242c /* Ga calibration register 32bit */
     50
     51#define MLX90632_EE_Gb		0x242e /* Gb calibration register 16bit */
     52#define MLX90632_EE_Ka		0x242f /* Ka calibration register 16bit */
     53
     54#define MLX90632_EE_Ha		0x2481 /* Ha customer calib value reg 16bit */
     55#define MLX90632_EE_Hb		0x2482 /* Hb customer calib value reg 16bit */
     56
     57/* Register addresses - volatile */
     58#define MLX90632_REG_I2C_ADDR	0x3000 /* Chip I2C address register */
     59
     60/* Control register address - volatile */
     61#define MLX90632_REG_CONTROL	0x3001 /* Control Register address */
     62#define   MLX90632_CFG_PWR_MASK		GENMASK(2, 1) /* PowerMode Mask */
     63#define   MLX90632_CFG_MTYP_MASK		GENMASK(8, 4) /* Meas select Mask */
     64
     65/* PowerModes statuses */
     66#define MLX90632_PWR_STATUS(ctrl_val) (ctrl_val << 1)
     67#define MLX90632_PWR_STATUS_HALT MLX90632_PWR_STATUS(0) /* hold */
     68#define MLX90632_PWR_STATUS_SLEEP_STEP MLX90632_PWR_STATUS(1) /* sleep step*/
     69#define MLX90632_PWR_STATUS_STEP MLX90632_PWR_STATUS(2) /* step */
     70#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous*/
     71
     72/* Measurement types */
     73#define MLX90632_MTYP_MEDICAL 0
     74#define MLX90632_MTYP_EXTENDED 17
     75
     76/* Measurement type select*/
     77#define MLX90632_MTYP_STATUS(ctrl_val) (ctrl_val << 4)
     78#define MLX90632_MTYP_STATUS_MEDICAL MLX90632_MTYP_STATUS(MLX90632_MTYP_MEDICAL)
     79#define MLX90632_MTYP_STATUS_EXTENDED MLX90632_MTYP_STATUS(MLX90632_MTYP_EXTENDED)
     80
     81/* I2C command register - volatile */
     82#define MLX90632_REG_I2C_CMD    0x3005 /* I2C command Register address */
     83
     84/* Device status register - volatile */
     85#define MLX90632_REG_STATUS	0x3fff /* Device status register */
     86#define   MLX90632_STAT_BUSY		BIT(10) /* Device busy indicator */
     87#define   MLX90632_STAT_EE_BUSY		BIT(9) /* EEPROM busy indicator */
     88#define   MLX90632_STAT_BRST		BIT(8) /* Brown out reset indicator */
     89#define   MLX90632_STAT_CYCLE_POS	GENMASK(6, 2) /* Data position */
     90#define   MLX90632_STAT_DATA_RDY	BIT(0) /* Data ready indicator */
     91
     92/* RAM_MEAS address-es for each channel */
     93#define MLX90632_RAM_1(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num)
     94#define MLX90632_RAM_2(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num + 1)
     95#define MLX90632_RAM_3(meas_num)	(MLX90632_ADDR_RAM + 3 * meas_num + 2)
     96
     97/* Name important RAM_MEAS channels */
     98#define MLX90632_RAM_DSP5_EXTENDED_AMBIENT_1 MLX90632_RAM_3(17)
     99#define MLX90632_RAM_DSP5_EXTENDED_AMBIENT_2 MLX90632_RAM_3(18)
    100#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_1 MLX90632_RAM_1(17)
    101#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_2 MLX90632_RAM_2(17)
    102#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_3 MLX90632_RAM_1(18)
    103#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_4 MLX90632_RAM_2(18)
    104#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_5 MLX90632_RAM_1(19)
    105#define MLX90632_RAM_DSP5_EXTENDED_OBJECT_6 MLX90632_RAM_2(19)
    106
    107/* Magic constants */
    108#define MLX90632_ID_MEDICAL	0x0105 /* EEPROM DSPv5 Medical device id */
    109#define MLX90632_ID_CONSUMER	0x0205 /* EEPROM DSPv5 Consumer device id */
    110#define MLX90632_ID_EXTENDED	0x0505 /* EEPROM DSPv5 Extended range device id */
    111#define MLX90632_ID_MASK	GENMASK(14, 0) /* DSP version and device ID in EE_VERSION */
    112#define MLX90632_DSP_VERSION	5 /* DSP version */
    113#define MLX90632_DSP_MASK	GENMASK(7, 0) /* DSP version in EE_VERSION */
    114#define MLX90632_RESET_CMD	0x0006 /* Reset sensor (address or global) */
    115#define MLX90632_REF_12 	12LL /* ResCtrlRef value of Ch 1 or Ch 2 */
    116#define MLX90632_REF_3		12LL /* ResCtrlRef value of Channel 3 */
    117#define MLX90632_MAX_MEAS_NUM	31 /* Maximum measurements in list */
    118#define MLX90632_SLEEP_DELAY_MS 3000 /* Autosleep delay */
    119#define MLX90632_EXTENDED_LIMIT 27000 /* Extended mode raw value limit */
    120
    121/**
    122 * struct mlx90632_data - private data for the MLX90632 device
    123 * @client: I2C client of the device
    124 * @lock: Internal mutex for multiple reads for single measurement
    125 * @regmap: Regmap of the device
    126 * @emissivity: Object emissivity from 0 to 1000 where 1000 = 1.
    127 * @mtyp: Measurement type physical sensor configuration for extended range
    128 *        calculations
    129 * @object_ambient_temperature: Ambient temperature at object (might differ of
    130 *                              the ambient temperature of sensor.
    131 */
    132struct mlx90632_data {
    133	struct i2c_client *client;
    134	struct mutex lock;
    135	struct regmap *regmap;
    136	u16 emissivity;
    137	u8 mtyp;
    138	u32 object_ambient_temperature;
    139};
    140
    141static const struct regmap_range mlx90632_volatile_reg_range[] = {
    142	regmap_reg_range(MLX90632_REG_I2C_ADDR, MLX90632_REG_CONTROL),
    143	regmap_reg_range(MLX90632_REG_I2C_CMD, MLX90632_REG_I2C_CMD),
    144	regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
    145	regmap_reg_range(MLX90632_RAM_1(0),
    146			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
    147};
    148
    149static const struct regmap_access_table mlx90632_volatile_regs_tbl = {
    150	.yes_ranges = mlx90632_volatile_reg_range,
    151	.n_yes_ranges = ARRAY_SIZE(mlx90632_volatile_reg_range),
    152};
    153
    154static const struct regmap_range mlx90632_read_reg_range[] = {
    155	regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
    156	regmap_reg_range(MLX90632_EE_CTRL, MLX90632_EE_I2C_ADDR),
    157	regmap_reg_range(MLX90632_EE_Ha, MLX90632_EE_Hb),
    158	regmap_reg_range(MLX90632_REG_I2C_ADDR, MLX90632_REG_CONTROL),
    159	regmap_reg_range(MLX90632_REG_I2C_CMD, MLX90632_REG_I2C_CMD),
    160	regmap_reg_range(MLX90632_REG_STATUS, MLX90632_REG_STATUS),
    161	regmap_reg_range(MLX90632_RAM_1(0),
    162			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
    163};
    164
    165static const struct regmap_access_table mlx90632_readable_regs_tbl = {
    166	.yes_ranges = mlx90632_read_reg_range,
    167	.n_yes_ranges = ARRAY_SIZE(mlx90632_read_reg_range),
    168};
    169
    170static const struct regmap_range mlx90632_no_write_reg_range[] = {
    171	regmap_reg_range(MLX90632_EE_VERSION, MLX90632_EE_Ka),
    172	regmap_reg_range(MLX90632_RAM_1(0),
    173			 MLX90632_RAM_3(MLX90632_MAX_MEAS_NUM)),
    174};
    175
    176static const struct regmap_access_table mlx90632_writeable_regs_tbl = {
    177	.no_ranges = mlx90632_no_write_reg_range,
    178	.n_no_ranges = ARRAY_SIZE(mlx90632_no_write_reg_range),
    179};
    180
    181static const struct regmap_config mlx90632_regmap = {
    182	.reg_bits = 16,
    183	.val_bits = 16,
    184
    185	.volatile_table = &mlx90632_volatile_regs_tbl,
    186	.rd_table = &mlx90632_readable_regs_tbl,
    187	.wr_table = &mlx90632_writeable_regs_tbl,
    188
    189	.use_single_read = true,
    190	.use_single_write = true,
    191	.reg_format_endian = REGMAP_ENDIAN_BIG,
    192	.val_format_endian = REGMAP_ENDIAN_BIG,
    193	.cache_type = REGCACHE_RBTREE,
    194};
    195
    196static s32 mlx90632_pwr_set_sleep_step(struct regmap *regmap)
    197{
    198	return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
    199				  MLX90632_CFG_PWR_MASK,
    200				  MLX90632_PWR_STATUS_SLEEP_STEP);
    201}
    202
    203static s32 mlx90632_pwr_continuous(struct regmap *regmap)
    204{
    205	return regmap_update_bits(regmap, MLX90632_REG_CONTROL,
    206				  MLX90632_CFG_PWR_MASK,
    207				  MLX90632_PWR_STATUS_CONTINUOUS);
    208}
    209
    210/**
    211 * mlx90632_perform_measurement() - Trigger and retrieve current measurement cycle
    212 * @data: pointer to mlx90632_data object containing regmap information
    213 *
    214 * Perform a measurement and return latest measurement cycle position reported
    215 * by sensor. This is a blocking function for 500ms, as that is default sensor
    216 * refresh rate.
    217 */
    218static int mlx90632_perform_measurement(struct mlx90632_data *data)
    219{
    220	unsigned int reg_status;
    221	int ret;
    222
    223	ret = regmap_update_bits(data->regmap, MLX90632_REG_STATUS,
    224				 MLX90632_STAT_DATA_RDY, 0);
    225	if (ret < 0)
    226		return ret;
    227
    228	ret = regmap_read_poll_timeout(data->regmap, MLX90632_REG_STATUS, reg_status,
    229				       !(reg_status & MLX90632_STAT_DATA_RDY), 10000,
    230				       100 * 10000);
    231
    232	if (ret < 0) {
    233		dev_err(&data->client->dev, "data not ready");
    234		return -ETIMEDOUT;
    235	}
    236
    237	return (reg_status & MLX90632_STAT_CYCLE_POS) >> 2;
    238}
    239
    240static int mlx90632_set_meas_type(struct regmap *regmap, u8 type)
    241{
    242	int ret;
    243
    244	if ((type != MLX90632_MTYP_MEDICAL) && (type != MLX90632_MTYP_EXTENDED))
    245		return -EINVAL;
    246
    247	ret = regmap_write(regmap, MLX90632_REG_I2C_CMD, MLX90632_RESET_CMD);
    248	if (ret < 0)
    249		return ret;
    250
    251	/*
    252	 * Give the mlx90632 some time to reset properly before sending a new I2C command
    253	 * if this is not done, the following I2C command(s) will not be accepted.
    254	 */
    255	usleep_range(150, 200);
    256
    257	ret = regmap_write_bits(regmap, MLX90632_REG_CONTROL,
    258				 (MLX90632_CFG_MTYP_MASK | MLX90632_CFG_PWR_MASK),
    259				 (MLX90632_MTYP_STATUS(type) | MLX90632_PWR_STATUS_HALT));
    260	if (ret < 0)
    261		return ret;
    262
    263	return mlx90632_pwr_continuous(regmap);
    264}
    265
    266static int mlx90632_channel_new_select(int perform_ret, uint8_t *channel_new,
    267				       uint8_t *channel_old)
    268{
    269	switch (perform_ret) {
    270	case 1:
    271		*channel_new = 1;
    272		*channel_old = 2;
    273		break;
    274	case 2:
    275		*channel_new = 2;
    276		*channel_old = 1;
    277		break;
    278	default:
    279		return -EINVAL;
    280	}
    281
    282	return 0;
    283}
    284
    285static int mlx90632_read_ambient_raw(struct regmap *regmap,
    286				     s16 *ambient_new_raw, s16 *ambient_old_raw)
    287{
    288	int ret;
    289	unsigned int read_tmp;
    290
    291	ret = regmap_read(regmap, MLX90632_RAM_3(1), &read_tmp);
    292	if (ret < 0)
    293		return ret;
    294	*ambient_new_raw = (s16)read_tmp;
    295
    296	ret = regmap_read(regmap, MLX90632_RAM_3(2), &read_tmp);
    297	if (ret < 0)
    298		return ret;
    299	*ambient_old_raw = (s16)read_tmp;
    300
    301	return ret;
    302}
    303
    304static int mlx90632_read_object_raw(struct regmap *regmap,
    305				    int perform_measurement_ret,
    306				    s16 *object_new_raw, s16 *object_old_raw)
    307{
    308	int ret;
    309	unsigned int read_tmp;
    310	s16 read;
    311	u8 channel = 0;
    312	u8 channel_old = 0;
    313
    314	ret = mlx90632_channel_new_select(perform_measurement_ret, &channel,
    315					  &channel_old);
    316	if (ret != 0)
    317		return ret;
    318
    319	ret = regmap_read(regmap, MLX90632_RAM_2(channel), &read_tmp);
    320	if (ret < 0)
    321		return ret;
    322
    323	read = (s16)read_tmp;
    324
    325	ret = regmap_read(regmap, MLX90632_RAM_1(channel), &read_tmp);
    326	if (ret < 0)
    327		return ret;
    328	*object_new_raw = (read + (s16)read_tmp) / 2;
    329
    330	ret = regmap_read(regmap, MLX90632_RAM_2(channel_old), &read_tmp);
    331	if (ret < 0)
    332		return ret;
    333	read = (s16)read_tmp;
    334
    335	ret = regmap_read(regmap, MLX90632_RAM_1(channel_old), &read_tmp);
    336	if (ret < 0)
    337		return ret;
    338	*object_old_raw = (read + (s16)read_tmp) / 2;
    339
    340	return ret;
    341}
    342
    343static int mlx90632_read_all_channel(struct mlx90632_data *data,
    344				     s16 *ambient_new_raw, s16 *ambient_old_raw,
    345				     s16 *object_new_raw, s16 *object_old_raw)
    346{
    347	s32 ret, measurement;
    348
    349	mutex_lock(&data->lock);
    350	measurement = mlx90632_perform_measurement(data);
    351	if (measurement < 0) {
    352		ret = measurement;
    353		goto read_unlock;
    354	}
    355	ret = mlx90632_read_ambient_raw(data->regmap, ambient_new_raw,
    356					ambient_old_raw);
    357	if (ret < 0)
    358		goto read_unlock;
    359
    360	ret = mlx90632_read_object_raw(data->regmap, measurement,
    361				       object_new_raw, object_old_raw);
    362read_unlock:
    363	mutex_unlock(&data->lock);
    364	return ret;
    365}
    366
    367static int mlx90632_read_ambient_raw_extended(struct regmap *regmap,
    368					      s16 *ambient_new_raw, s16 *ambient_old_raw)
    369{
    370	unsigned int read_tmp;
    371	int ret;
    372
    373	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_AMBIENT_1, &read_tmp);
    374	if (ret < 0)
    375		return ret;
    376	*ambient_new_raw = (s16)read_tmp;
    377
    378	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_AMBIENT_2, &read_tmp);
    379	if (ret < 0)
    380		return ret;
    381	*ambient_old_raw = (s16)read_tmp;
    382
    383	return 0;
    384}
    385
    386static int mlx90632_read_object_raw_extended(struct regmap *regmap, s16 *object_new_raw)
    387{
    388	unsigned int read_tmp;
    389	s32 read;
    390	int ret;
    391
    392	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_1, &read_tmp);
    393	if (ret < 0)
    394		return ret;
    395	read = (s16)read_tmp;
    396
    397	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_2, &read_tmp);
    398	if (ret < 0)
    399		return ret;
    400	read = read - (s16)read_tmp;
    401
    402	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_3, &read_tmp);
    403	if (ret < 0)
    404		return ret;
    405	read = read - (s16)read_tmp;
    406
    407	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_4, &read_tmp);
    408	if (ret < 0)
    409		return ret;
    410	read = (read + (s16)read_tmp) / 2;
    411
    412	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_5, &read_tmp);
    413	if (ret < 0)
    414		return ret;
    415	read = read + (s16)read_tmp;
    416
    417	ret = regmap_read(regmap, MLX90632_RAM_DSP5_EXTENDED_OBJECT_6, &read_tmp);
    418	if (ret < 0)
    419		return ret;
    420	read = read + (s16)read_tmp;
    421
    422	if (read > S16_MAX || read < S16_MIN)
    423		return -ERANGE;
    424
    425	*object_new_raw = read;
    426
    427	return 0;
    428}
    429
    430static int mlx90632_read_all_channel_extended(struct mlx90632_data *data, s16 *object_new_raw,
    431					      s16 *ambient_new_raw, s16 *ambient_old_raw)
    432{
    433	s32 ret, meas;
    434
    435	mutex_lock(&data->lock);
    436	ret = mlx90632_set_meas_type(data->regmap, MLX90632_MTYP_EXTENDED);
    437	if (ret < 0)
    438		goto read_unlock;
    439
    440	ret = read_poll_timeout(mlx90632_perform_measurement, meas, meas == 19,
    441				50000, 800000, false, data);
    442	if (ret != 0)
    443		goto read_unlock;
    444
    445	ret = mlx90632_read_object_raw_extended(data->regmap, object_new_raw);
    446	if (ret < 0)
    447		goto read_unlock;
    448
    449	ret = mlx90632_read_ambient_raw_extended(data->regmap, ambient_new_raw, ambient_old_raw);
    450
    451read_unlock:
    452	(void) mlx90632_set_meas_type(data->regmap, MLX90632_MTYP_MEDICAL);
    453
    454	mutex_unlock(&data->lock);
    455	return ret;
    456}
    457
    458static int mlx90632_read_ee_register(struct regmap *regmap, u16 reg_lsb,
    459				     s32 *reg_value)
    460{
    461	s32 ret;
    462	unsigned int read;
    463	u32 value;
    464
    465	ret = regmap_read(regmap, reg_lsb, &read);
    466	if (ret < 0)
    467		return ret;
    468
    469	value = read;
    470
    471	ret = regmap_read(regmap, reg_lsb + 1, &read);
    472	if (ret < 0)
    473		return ret;
    474
    475	*reg_value = (read << 16) | (value & 0xffff);
    476
    477	return 0;
    478}
    479
    480static s64 mlx90632_preprocess_temp_amb(s16 ambient_new_raw,
    481					s16 ambient_old_raw, s16 Gb)
    482{
    483	s64 VR_Ta, kGb, tmp;
    484
    485	kGb = ((s64)Gb * 1000LL) >> 10ULL;
    486	VR_Ta = (s64)ambient_old_raw * 1000000LL +
    487		kGb * div64_s64(((s64)ambient_new_raw * 1000LL),
    488			(MLX90632_REF_3));
    489	tmp = div64_s64(
    490			 div64_s64(((s64)ambient_new_raw * 1000000000000LL),
    491				   (MLX90632_REF_3)), VR_Ta);
    492	return div64_s64(tmp << 19ULL, 1000LL);
    493}
    494
    495static s64 mlx90632_preprocess_temp_obj(s16 object_new_raw, s16 object_old_raw,
    496					s16 ambient_new_raw,
    497					s16 ambient_old_raw, s16 Ka)
    498{
    499	s64 VR_IR, kKa, tmp;
    500
    501	kKa = ((s64)Ka * 1000LL) >> 10ULL;
    502	VR_IR = (s64)ambient_old_raw * 1000000LL +
    503		kKa * div64_s64(((s64)ambient_new_raw * 1000LL),
    504			(MLX90632_REF_3));
    505	tmp = div64_s64(
    506			div64_s64(((s64)((object_new_raw + object_old_raw) / 2)
    507				   * 1000000000000LL), (MLX90632_REF_12)),
    508			VR_IR);
    509	return div64_s64((tmp << 19ULL), 1000LL);
    510}
    511
    512static s64 mlx90632_preprocess_temp_obj_extended(s16 object_new_raw, s16 ambient_new_raw,
    513						 s16 ambient_old_raw, s16 Ka)
    514{
    515	s64 VR_IR, kKa, tmp;
    516
    517	kKa = ((s64)Ka * 1000LL) >> 10ULL;
    518	VR_IR = (s64)ambient_old_raw * 1000000LL +
    519		kKa * div64_s64((s64)ambient_new_raw * 1000LL,
    520				MLX90632_REF_3);
    521	tmp = div64_s64(
    522			div64_s64((s64) object_new_raw * 1000000000000LL, MLX90632_REF_12),
    523			VR_IR);
    524	return div64_s64(tmp << 19ULL, 1000LL);
    525}
    526
    527static s32 mlx90632_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
    528				      s32 P_T, s32 P_R, s32 P_G, s32 P_O, s16 Gb)
    529{
    530	s64 Asub, Bsub, Ablock, Bblock, Cblock, AMB, sum;
    531
    532	AMB = mlx90632_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
    533					   Gb);
    534	Asub = ((s64)P_T * 10000000000LL) >> 44ULL;
    535	Bsub = AMB - (((s64)P_R * 1000LL) >> 8ULL);
    536	Ablock = Asub * (Bsub * Bsub);
    537	Bblock = (div64_s64(Bsub * 10000000LL, P_G)) << 20ULL;
    538	Cblock = ((s64)P_O * 10000000000LL) >> 8ULL;
    539
    540	sum = div64_s64(Ablock, 1000000LL) + Bblock + Cblock;
    541
    542	return div64_s64(sum, 10000000LL);
    543}
    544
    545static s32 mlx90632_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
    546					       s64 TAdut, s64 TAdut4, s32 Fa, s32 Fb,
    547					       s32 Ga, s16 Ha, s16 Hb,
    548					       u16 emissivity)
    549{
    550	s64 calcedKsTO, calcedKsTA, ir_Alpha, Alpha_corr;
    551	s64 Ha_customer, Hb_customer;
    552
    553	Ha_customer = ((s64)Ha * 1000000LL) >> 14ULL;
    554	Hb_customer = ((s64)Hb * 100) >> 10ULL;
    555
    556	calcedKsTO = ((s64)((s64)Ga * (prev_object_temp - 25 * 1000LL)
    557			     * 1000LL)) >> 36LL;
    558	calcedKsTA = ((s64)(Fb * (TAdut - 25 * 1000000LL))) >> 36LL;
    559	Alpha_corr = div64_s64((((s64)(Fa * 10000000000LL) >> 46LL)
    560				* Ha_customer), 1000LL);
    561	Alpha_corr *= ((s64)(1 * 1000000LL + calcedKsTO + calcedKsTA));
    562	Alpha_corr = emissivity * div64_s64(Alpha_corr, 100000LL);
    563	Alpha_corr = div64_s64(Alpha_corr, 1000LL);
    564	ir_Alpha = div64_s64((s64)object * 10000000LL, Alpha_corr);
    565
    566	return (int_sqrt64(int_sqrt64(ir_Alpha * 1000000000000LL + TAdut4))
    567		- 27315 - Hb_customer) * 10;
    568}
    569
    570static s64 mlx90632_calc_ta4(s64 TAdut, s64 scale)
    571{
    572	return (div64_s64(TAdut, scale) + 27315) *
    573		(div64_s64(TAdut, scale) + 27315) *
    574		(div64_s64(TAdut, scale) + 27315) *
    575		(div64_s64(TAdut, scale) + 27315);
    576}
    577
    578static s32 mlx90632_calc_temp_object(s64 object, s64 ambient, s32 Ea, s32 Eb,
    579				     s32 Fa, s32 Fb, s32 Ga, s16 Ha, s16 Hb,
    580				     u16 tmp_emi)
    581{
    582	s64 kTA, kTA0, TAdut, TAdut4;
    583	s64 temp = 25000;
    584	s8 i;
    585
    586	kTA = (Ea * 1000LL) >> 16LL;
    587	kTA0 = (Eb * 1000LL) >> 8LL;
    588	TAdut = div64_s64(((ambient - kTA0) * 1000000LL), kTA) + 25 * 1000000LL;
    589	TAdut4 = mlx90632_calc_ta4(TAdut, 10000LL);
    590
    591	/* Iterations of calculation as described in datasheet */
    592	for (i = 0; i < 5; ++i) {
    593		temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut, TAdut4,
    594							   Fa, Fb, Ga, Ha, Hb,
    595							   tmp_emi);
    596	}
    597	return temp;
    598}
    599
    600static s32 mlx90632_calc_temp_object_extended(s64 object, s64 ambient, s64 reflected,
    601					      s32 Ea, s32 Eb, s32 Fa, s32 Fb, s32 Ga,
    602					      s16 Ha, s16 Hb, u16 tmp_emi)
    603{
    604	s64 kTA, kTA0, TAdut, TAdut4, Tr4, TaTr4;
    605	s64 temp = 25000;
    606	s8 i;
    607
    608	kTA = (Ea * 1000LL) >> 16LL;
    609	kTA0 = (Eb * 1000LL) >> 8LL;
    610	TAdut = div64_s64((ambient - kTA0) * 1000000LL, kTA) + 25 * 1000000LL;
    611	Tr4 = mlx90632_calc_ta4(reflected, 10);
    612	TAdut4 = mlx90632_calc_ta4(TAdut, 10000LL);
    613	TaTr4 = Tr4 - div64_s64(Tr4 - TAdut4, tmp_emi) * 1000;
    614
    615	/* Iterations of calculation as described in datasheet */
    616	for (i = 0; i < 5; ++i) {
    617		temp = mlx90632_calc_temp_object_iteration(temp, object, TAdut, TaTr4,
    618							   Fa / 2, Fb, Ga, Ha, Hb,
    619							   tmp_emi);
    620	}
    621
    622	return temp;
    623}
    624
    625static int mlx90632_calc_object_dsp105(struct mlx90632_data *data, int *val)
    626{
    627	s32 ret;
    628	s32 Ea, Eb, Fa, Fb, Ga;
    629	unsigned int read_tmp;
    630	s16 Ha, Hb, Gb, Ka;
    631	s16 ambient_new_raw, ambient_old_raw, object_new_raw, object_old_raw;
    632	s64 object, ambient;
    633
    634	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ea, &Ea);
    635	if (ret < 0)
    636		return ret;
    637	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Eb, &Eb);
    638	if (ret < 0)
    639		return ret;
    640	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fa, &Fa);
    641	if (ret < 0)
    642		return ret;
    643	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Fb, &Fb);
    644	if (ret < 0)
    645		return ret;
    646	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_Ga, &Ga);
    647	if (ret < 0)
    648		return ret;
    649	ret = regmap_read(data->regmap, MLX90632_EE_Ha, &read_tmp);
    650	if (ret < 0)
    651		return ret;
    652	Ha = (s16)read_tmp;
    653	ret = regmap_read(data->regmap, MLX90632_EE_Hb, &read_tmp);
    654	if (ret < 0)
    655		return ret;
    656	Hb = (s16)read_tmp;
    657	ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
    658	if (ret < 0)
    659		return ret;
    660	Gb = (s16)read_tmp;
    661	ret = regmap_read(data->regmap, MLX90632_EE_Ka, &read_tmp);
    662	if (ret < 0)
    663		return ret;
    664	Ka = (s16)read_tmp;
    665
    666	ret = mlx90632_read_all_channel(data,
    667					&ambient_new_raw, &ambient_old_raw,
    668					&object_new_raw, &object_old_raw);
    669	if (ret < 0)
    670		return ret;
    671
    672	if (object_new_raw > MLX90632_EXTENDED_LIMIT &&
    673	    data->mtyp == MLX90632_MTYP_EXTENDED) {
    674		ret = mlx90632_read_all_channel_extended(data, &object_new_raw,
    675							 &ambient_new_raw, &ambient_old_raw);
    676		if (ret < 0)
    677			return ret;
    678
    679		/* Use extended mode calculations */
    680		ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
    681						       ambient_old_raw, Gb);
    682		object = mlx90632_preprocess_temp_obj_extended(object_new_raw,
    683							       ambient_new_raw,
    684							       ambient_old_raw, Ka);
    685		*val = mlx90632_calc_temp_object_extended(object, ambient,
    686							  data->object_ambient_temperature,
    687							  Ea, Eb, Fa, Fb, Ga,
    688							  Ha, Hb, data->emissivity);
    689		return 0;
    690	}
    691
    692	ambient = mlx90632_preprocess_temp_amb(ambient_new_raw,
    693					       ambient_old_raw, Gb);
    694	object = mlx90632_preprocess_temp_obj(object_new_raw,
    695					      object_old_raw,
    696					      ambient_new_raw,
    697					      ambient_old_raw, Ka);
    698
    699	*val = mlx90632_calc_temp_object(object, ambient, Ea, Eb, Fa, Fb, Ga,
    700					 Ha, Hb, data->emissivity);
    701	return 0;
    702}
    703
    704static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
    705{
    706	s32 ret;
    707	unsigned int read_tmp;
    708	s32 PT, PR, PG, PO;
    709	s16 Gb;
    710	s16 ambient_new_raw, ambient_old_raw;
    711
    712	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_R, &PR);
    713	if (ret < 0)
    714		return ret;
    715	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_G, &PG);
    716	if (ret < 0)
    717		return ret;
    718	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_T, &PT);
    719	if (ret < 0)
    720		return ret;
    721	ret = mlx90632_read_ee_register(data->regmap, MLX90632_EE_P_O, &PO);
    722	if (ret < 0)
    723		return ret;
    724	ret = regmap_read(data->regmap, MLX90632_EE_Gb, &read_tmp);
    725	if (ret < 0)
    726		return ret;
    727	Gb = (s16)read_tmp;
    728
    729	ret = mlx90632_read_ambient_raw(data->regmap, &ambient_new_raw,
    730					&ambient_old_raw);
    731	if (ret < 0)
    732		return ret;
    733	*val = mlx90632_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
    734					  PT, PR, PG, PO, Gb);
    735	return ret;
    736}
    737
    738static int mlx90632_read_raw(struct iio_dev *indio_dev,
    739			     struct iio_chan_spec const *channel, int *val,
    740			     int *val2, long mask)
    741{
    742	struct mlx90632_data *data = iio_priv(indio_dev);
    743	int ret;
    744
    745	switch (mask) {
    746	case IIO_CHAN_INFO_PROCESSED:
    747		switch (channel->channel2) {
    748		case IIO_MOD_TEMP_AMBIENT:
    749			ret = mlx90632_calc_ambient_dsp105(data, val);
    750			if (ret < 0)
    751				return ret;
    752			return IIO_VAL_INT;
    753		case IIO_MOD_TEMP_OBJECT:
    754			ret = mlx90632_calc_object_dsp105(data, val);
    755			if (ret < 0)
    756				return ret;
    757			return IIO_VAL_INT;
    758		default:
    759			return -EINVAL;
    760		}
    761	case IIO_CHAN_INFO_CALIBEMISSIVITY:
    762		if (data->emissivity == 1000) {
    763			*val = 1;
    764			*val2 = 0;
    765		} else {
    766			*val = 0;
    767			*val2 = data->emissivity * 1000;
    768		}
    769		return IIO_VAL_INT_PLUS_MICRO;
    770	case IIO_CHAN_INFO_CALIBAMBIENT:
    771		*val = data->object_ambient_temperature;
    772		return IIO_VAL_INT;
    773	default:
    774		return -EINVAL;
    775	}
    776}
    777
    778static int mlx90632_write_raw(struct iio_dev *indio_dev,
    779			      struct iio_chan_spec const *channel, int val,
    780			      int val2, long mask)
    781{
    782	struct mlx90632_data *data = iio_priv(indio_dev);
    783
    784	switch (mask) {
    785	case IIO_CHAN_INFO_CALIBEMISSIVITY:
    786		/* Confirm we are within 0 and 1.0 */
    787		if (val < 0 || val2 < 0 || val > 1 ||
    788		    (val == 1 && val2 != 0))
    789			return -EINVAL;
    790		data->emissivity = val * 1000 + val2 / 1000;
    791		return 0;
    792	case IIO_CHAN_INFO_CALIBAMBIENT:
    793		data->object_ambient_temperature = val;
    794		return 0;
    795	default:
    796		return -EINVAL;
    797	}
    798}
    799
    800static const struct iio_chan_spec mlx90632_channels[] = {
    801	{
    802		.type = IIO_TEMP,
    803		.modified = 1,
    804		.channel2 = IIO_MOD_TEMP_AMBIENT,
    805		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
    806	},
    807	{
    808		.type = IIO_TEMP,
    809		.modified = 1,
    810		.channel2 = IIO_MOD_TEMP_OBJECT,
    811		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
    812			BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) | BIT(IIO_CHAN_INFO_CALIBAMBIENT),
    813	},
    814};
    815
    816static const struct iio_info mlx90632_info = {
    817	.read_raw = mlx90632_read_raw,
    818	.write_raw = mlx90632_write_raw,
    819};
    820
    821static int mlx90632_sleep(struct mlx90632_data *data)
    822{
    823	regcache_mark_dirty(data->regmap);
    824
    825	dev_dbg(&data->client->dev, "Requesting sleep");
    826	return mlx90632_pwr_set_sleep_step(data->regmap);
    827}
    828
    829static int mlx90632_wakeup(struct mlx90632_data *data)
    830{
    831	int ret;
    832
    833	ret = regcache_sync(data->regmap);
    834	if (ret < 0) {
    835		dev_err(&data->client->dev,
    836			"Failed to sync regmap registers: %d\n", ret);
    837		return ret;
    838	}
    839
    840	dev_dbg(&data->client->dev, "Requesting wake-up\n");
    841	return mlx90632_pwr_continuous(data->regmap);
    842}
    843
    844static int mlx90632_probe(struct i2c_client *client,
    845			  const struct i2c_device_id *id)
    846{
    847	struct iio_dev *indio_dev;
    848	struct mlx90632_data *mlx90632;
    849	struct regmap *regmap;
    850	int ret;
    851	unsigned int read;
    852
    853	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90632));
    854	if (!indio_dev) {
    855		dev_err(&client->dev, "Failed to allocate device\n");
    856		return -ENOMEM;
    857	}
    858
    859	regmap = devm_regmap_init_i2c(client, &mlx90632_regmap);
    860	if (IS_ERR(regmap)) {
    861		ret = PTR_ERR(regmap);
    862		dev_err(&client->dev, "Failed to allocate regmap: %d\n", ret);
    863		return ret;
    864	}
    865
    866	mlx90632 = iio_priv(indio_dev);
    867	i2c_set_clientdata(client, indio_dev);
    868	mlx90632->client = client;
    869	mlx90632->regmap = regmap;
    870	mlx90632->mtyp = MLX90632_MTYP_MEDICAL;
    871
    872	mutex_init(&mlx90632->lock);
    873	indio_dev->name = id->name;
    874	indio_dev->modes = INDIO_DIRECT_MODE;
    875	indio_dev->info = &mlx90632_info;
    876	indio_dev->channels = mlx90632_channels;
    877	indio_dev->num_channels = ARRAY_SIZE(mlx90632_channels);
    878
    879	ret = mlx90632_wakeup(mlx90632);
    880	if (ret < 0) {
    881		dev_err(&client->dev, "Wakeup failed: %d\n", ret);
    882		return ret;
    883	}
    884
    885	ret = regmap_read(mlx90632->regmap, MLX90632_EE_VERSION, &read);
    886	if (ret < 0) {
    887		dev_err(&client->dev, "read of version failed: %d\n", ret);
    888		return ret;
    889	}
    890	read = read & MLX90632_ID_MASK;
    891	if (read == MLX90632_ID_MEDICAL) {
    892		dev_dbg(&client->dev,
    893			"Detected Medical EEPROM calibration %x\n", read);
    894	} else if (read == MLX90632_ID_CONSUMER) {
    895		dev_dbg(&client->dev,
    896			"Detected Consumer EEPROM calibration %x\n", read);
    897	} else if (read == MLX90632_ID_EXTENDED) {
    898		dev_dbg(&client->dev,
    899			"Detected Extended range EEPROM calibration %x\n", read);
    900		mlx90632->mtyp = MLX90632_MTYP_EXTENDED;
    901	} else if ((read & MLX90632_DSP_MASK) == MLX90632_DSP_VERSION) {
    902		dev_dbg(&client->dev,
    903			"Detected Unknown EEPROM calibration %x\n", read);
    904	} else {
    905		dev_err(&client->dev,
    906			"Wrong DSP version %x (expected %x)\n",
    907			read, MLX90632_DSP_VERSION);
    908		return -EPROTONOSUPPORT;
    909	}
    910
    911	mlx90632->emissivity = 1000;
    912	mlx90632->object_ambient_temperature = 25000; /* 25 degrees milliCelsius */
    913
    914	pm_runtime_disable(&client->dev);
    915	ret = pm_runtime_set_active(&client->dev);
    916	if (ret < 0) {
    917		mlx90632_sleep(mlx90632);
    918		return ret;
    919	}
    920	pm_runtime_enable(&client->dev);
    921	pm_runtime_set_autosuspend_delay(&client->dev, MLX90632_SLEEP_DELAY_MS);
    922	pm_runtime_use_autosuspend(&client->dev);
    923
    924	return iio_device_register(indio_dev);
    925}
    926
    927static int mlx90632_remove(struct i2c_client *client)
    928{
    929	struct iio_dev *indio_dev = i2c_get_clientdata(client);
    930	struct mlx90632_data *data = iio_priv(indio_dev);
    931
    932	iio_device_unregister(indio_dev);
    933
    934	pm_runtime_disable(&client->dev);
    935	pm_runtime_set_suspended(&client->dev);
    936	pm_runtime_put_noidle(&client->dev);
    937
    938	mlx90632_sleep(data);
    939
    940	return 0;
    941}
    942
    943static const struct i2c_device_id mlx90632_id[] = {
    944	{ "mlx90632", 0 },
    945	{ }
    946};
    947MODULE_DEVICE_TABLE(i2c, mlx90632_id);
    948
    949static const struct of_device_id mlx90632_of_match[] = {
    950	{ .compatible = "melexis,mlx90632" },
    951	{ }
    952};
    953MODULE_DEVICE_TABLE(of, mlx90632_of_match);
    954
    955static int __maybe_unused mlx90632_pm_suspend(struct device *dev)
    956{
    957	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
    958	struct mlx90632_data *data = iio_priv(indio_dev);
    959
    960	return mlx90632_sleep(data);
    961}
    962
    963static int __maybe_unused mlx90632_pm_resume(struct device *dev)
    964{
    965	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
    966	struct mlx90632_data *data = iio_priv(indio_dev);
    967
    968	return mlx90632_wakeup(data);
    969}
    970
    971static UNIVERSAL_DEV_PM_OPS(mlx90632_pm_ops, mlx90632_pm_suspend,
    972			    mlx90632_pm_resume, NULL);
    973
    974static struct i2c_driver mlx90632_driver = {
    975	.driver = {
    976		.name	= "mlx90632",
    977		.of_match_table = mlx90632_of_match,
    978		.pm	= &mlx90632_pm_ops,
    979	},
    980	.probe = mlx90632_probe,
    981	.remove = mlx90632_remove,
    982	.id_table = mlx90632_id,
    983};
    984module_i2c_driver(mlx90632_driver);
    985
    986MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
    987MODULE_DESCRIPTION("Melexis MLX90632 contactless Infra Red temperature sensor driver");
    988MODULE_LICENSE("GPL v2");