blob: aeaa4da6923b416bb316f1afaab8f0eec1583c6b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for the Yamaha YAS magnetic sensors, often used in Samsung
* mobile phones. While all are not yet handled because of lacking
* hardware, expand this driver to handle the different variants:
*
* YAS530 MS-3E (2011 Samsung Galaxy S Advance)
* YAS532 MS-3R (2011 Samsung Galaxy S4)
* YAS533 MS-3F (Vivo 1633, 1707, V3, Y21L)
* (YAS534 is a magnetic switch, not handled)
* YAS535 MS-6C
* YAS536 MS-3W
* YAS537 MS-3T (2015 Samsung Galaxy S6, Note 5, Xiaomi)
* YAS539 MS-3S (2018 Samsung Galaxy A7 SM-A750FN)
*
* Code functions found in the MPU3050 YAS530 and YAS532 drivers
* named "inv_compass" in the Tegra Android kernel tree.
* Copyright (C) 2012 InvenSense Corporation
*
* Author: Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/random.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <asm/unaligned.h>
/* This register map covers YAS530 and YAS532 but differs in YAS 537 and YAS539 */
#define YAS5XX_DEVICE_ID 0x80
#define YAS5XX_ACTUATE_INIT_COIL 0x81
#define YAS5XX_MEASURE 0x82
#define YAS5XX_CONFIG 0x83
#define YAS5XX_MEASURE_INTERVAL 0x84
#define YAS5XX_OFFSET_X 0x85 /* [-31 .. 31] */
#define YAS5XX_OFFSET_Y1 0x86 /* [-31 .. 31] */
#define YAS5XX_OFFSET_Y2 0x87 /* [-31 .. 31] */
#define YAS5XX_TEST1 0x88
#define YAS5XX_TEST2 0x89
#define YAS5XX_CAL 0x90
#define YAS5XX_MEASURE_DATA 0xB0
/* Bits in the YAS5xx config register */
#define YAS5XX_CONFIG_INTON BIT(0) /* Interrupt on? */
#define YAS5XX_CONFIG_INTHACT BIT(1) /* Interrupt active high? */
#define YAS5XX_CONFIG_CCK_MASK GENMASK(4, 2)
#define YAS5XX_CONFIG_CCK_SHIFT 2
/* Bits in the measure command register */
#define YAS5XX_MEASURE_START BIT(0)
#define YAS5XX_MEASURE_LDTC BIT(1)
#define YAS5XX_MEASURE_FORS BIT(2)
#define YAS5XX_MEASURE_DLYMES BIT(4)
/* Bits in the measure data register */
#define YAS5XX_MEASURE_DATA_BUSY BIT(7)
#define YAS530_DEVICE_ID 0x01 /* YAS530 (MS-3E) */
#define YAS530_VERSION_A 0 /* YAS530 (MS-3E A) */
#define YAS530_VERSION_B 1 /* YAS530B (MS-3E B) */
#define YAS530_VERSION_A_COEF 380
#define YAS530_VERSION_B_COEF 550
#define YAS530_DATA_BITS 12
#define YAS530_DATA_CENTER BIT(YAS530_DATA_BITS - 1)
#define YAS530_DATA_OVERFLOW (BIT(YAS530_DATA_BITS) - 1)
#define YAS532_DEVICE_ID 0x02 /* YAS532/YAS533 (MS-3R/F) */
#define YAS532_VERSION_AB 0 /* YAS532/533 AB (MS-3R/F AB) */
#define YAS532_VERSION_AC 1 /* YAS532/533 AC (MS-3R/F AC) */
#define YAS532_VERSION_AB_COEF 1800
#define YAS532_VERSION_AC_COEF_X 850
#define YAS532_VERSION_AC_COEF_Y1 750
#define YAS532_VERSION_AC_COEF_Y2 750
#define YAS532_DATA_BITS 13
#define YAS532_DATA_CENTER BIT(YAS532_DATA_BITS - 1)
#define YAS532_DATA_OVERFLOW (BIT(YAS532_DATA_BITS) - 1)
#define YAS532_20DEGREES 390 /* Looks like Kelvin */
/* These variant IDs are known from code dumps */
#define YAS537_DEVICE_ID 0x07 /* YAS537 (MS-3T) */
#define YAS539_DEVICE_ID 0x08 /* YAS539 (MS-3S) */
/* Turn off device regulators etc after 5 seconds of inactivity */
#define YAS5XX_AUTOSUSPEND_DELAY_MS 5000
struct yas5xx_calibration {
/* Linearization calibration x, y1, y2 */
s32 r[3];
u32 f[3];
/* Temperature compensation calibration */
s32 Cx, Cy1, Cy2;
/* Misc calibration coefficients */
s32 a2, a3, a4, a5, a6, a7, a8, a9, k;
/* clock divider */
u8 dck;
};
/**
* struct yas5xx - state container for the YAS5xx driver
* @dev: parent device pointer
* @devid: device ID number
* @version: device version
* @name: device name
* @calibration: calibration settings from the OTP storage
* @hard_offsets: offsets for each axis measured with initcoil actuated
* @orientation: mounting matrix, flipped axis etc
* @map: regmap to access the YAX5xx registers over I2C
* @regs: the vdd and vddio power regulators
* @reset: optional GPIO line used for handling RESET
* @lock: locks the magnetometer for exclusive use during a measurement (which
* involves several register transactions so the regmap lock is not enough)
* so that measurements get serialized in a first-come-first serve manner
* @scan: naturally aligned measurements
*/
struct yas5xx {
struct device *dev;
unsigned int devid;
unsigned int version;
char name[16];
struct yas5xx_calibration calibration;
u8 hard_offsets[3];
struct iio_mount_matrix orientation;
struct regmap *map;
struct regulator_bulk_data regs[2];
struct gpio_desc *reset;
struct mutex lock;
/*
* The scanout is 4 x 32 bits in CPU endianness.
* Ensure timestamp is naturally aligned
*/
struct {
s32 channels[4];
s64 ts __aligned(8);
} scan;
};
/* On YAS530 the x, y1 and y2 values are 12 bits */
static u16 yas530_extract_axis(u8 *data)
{
u16 val;
/*
* These are the bits used in a 16bit word:
* 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
* x x x x x x x x x x x x
*/
val = get_unaligned_be16(&data[0]);
val = FIELD_GET(GENMASK(14, 3), val);
return val;
}
/* On YAS532 the x, y1 and y2 values are 13 bits */
static u16 yas532_extract_axis(u8 *data)
{
u16 val;
/*
* These are the bits used in a 16bit word:
* 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
* x x x x x x x x x x x x x
*/
val = get_unaligned_be16(&data[0]);
val = FIELD_GET(GENMASK(14, 2), val);
return val;
}
/**
* yas5xx_measure() - Make a measure from the hardware
* @yas5xx: The device state
* @t: the raw temperature measurement
* @x: the raw x axis measurement
* @y1: the y1 axis measurement
* @y2: the y2 axis measurement
* @return: 0 on success or error code
*/
static int yas5xx_measure(struct yas5xx *yas5xx, u16 *t, u16 *x, u16 *y1, u16 *y2)
{
unsigned int busy;
u8 data[8];
int ret;
u16 val;
mutex_lock(&yas5xx->lock);
ret = regmap_write(yas5xx->map, YAS5XX_MEASURE, YAS5XX_MEASURE_START);
if (ret < 0)
goto out_unlock;
/*
* Typical time to measure 1500 us, max 2000 us so wait min 500 us
* and at most 20000 us (one magnitude more than the datsheet max)
* before timeout.
*/
ret = regmap_read_poll_timeout(yas5xx->map, YAS5XX_MEASURE_DATA, busy,
!(busy & YAS5XX_MEASURE_DATA_BUSY),
500, 20000);
if (ret) {
dev_err(yas5xx->dev, "timeout waiting for measurement\n");
goto out_unlock;
}
ret = regmap_bulk_read(yas5xx->map, YAS5XX_MEASURE_DATA,
data, sizeof(data));
if (ret)
goto out_unlock;
mutex_unlock(&yas5xx->lock);
switch (yas5xx->devid) {
case YAS530_DEVICE_ID:
/*
* The t value is 9 bits in big endian format
* These are the bits used in a 16bit word:
* 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
* x x x x x x x x x
*/
val = get_unaligned_be16(&data[0]);
val = FIELD_GET(GENMASK(14, 6), val);
*t = val;
*x = yas530_extract_axis(&data[2]);
*y1 = yas530_extract_axis(&data[4]);
*y2 = yas530_extract_axis(&data[6]);
break;
case YAS532_DEVICE_ID:
/*
* The t value is 10 bits in big endian format
* These are the bits used in a 16bit word:
* 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
* x x x x x x x x x x
*/
val = get_unaligned_be16(&data[0]);
val = FIELD_GET(GENMASK(14, 5), val);
*t = val;
*x = yas532_extract_axis(&data[2]);
*y1 = yas532_extract_axis(&data[4]);
*y2 = yas532_extract_axis(&data[6]);
break;
default:
dev_err(yas5xx->dev, "unknown data format\n");
ret = -EINVAL;
break;
}
return ret;
out_unlock:
mutex_unlock(&yas5xx->lock);
return ret;
}
static s32 yas5xx_linearize(struct yas5xx *yas5xx, u16 val, int axis)
{
struct yas5xx_calibration *c = &yas5xx->calibration;
static const s32 yas532ac_coef[] = {
YAS532_VERSION_AC_COEF_X,
YAS532_VERSION_AC_COEF_Y1,
YAS532_VERSION_AC_COEF_Y2,
};
s32 coef;
/* Select coefficients */
switch (yas5xx->devid) {
case YAS530_DEVICE_ID:
if (yas5xx->version == YAS530_VERSION_A)
coef = YAS530_VERSION_A_COEF;
else
coef = YAS530_VERSION_B_COEF;
break;
case YAS532_DEVICE_ID:
if (yas5xx->version == YAS532_VERSION_AB)
coef = YAS532_VERSION_AB_COEF;
else
/* Elaborate coefficients */
coef = yas532ac_coef[axis];
break;
default:
dev_err(yas5xx->dev, "unknown device type\n");
return val;
}
/*
* Linearization formula:
*
* x' = x - (3721 + 50 * f) + (xoffset - r) * c
*
* Where f and r are calibration values, c is a per-device
* and sometimes per-axis coefficient.
*/
return val - (3721 + 50 * c->f[axis]) +
(yas5xx->hard_offsets[axis] - c->r[axis]) * coef;
}
/**
* yas5xx_get_measure() - Measure a sample of all axis and process
* @yas5xx: The device state
* @to: Temperature out
* @xo: X axis out
* @yo: Y axis out
* @zo: Z axis out
* @return: 0 on success or error code
*
* Returned values are in nanotesla according to some code.
*/
static int yas5xx_get_measure(struct yas5xx *yas5xx, s32 *to, s32 *xo, s32 *yo, s32 *zo)
{
struct yas5xx_calibration *c = &yas5xx->calibration;
u16 t, x, y1, y2;
/* These are "signed x, signed y1 etc */
s32 sx, sy1, sy2, sy, sz;
int ret;
/* We first get raw data that needs to be translated to [x,y,z] */
ret = yas5xx_measure(yas5xx, &t, &x, &y1, &y2);
if (ret)
return ret;
/* Do some linearization if available */
sx = yas5xx_linearize(yas5xx, x, 0);
sy1 = yas5xx_linearize(yas5xx, y1, 1);
sy2 = yas5xx_linearize(yas5xx, y2, 2);
/*
* Temperature compensation for x, y1, y2 respectively:
*
* Cx * t
* x' = x - ------
* 100
*/
sx = sx - (c->Cx * t) / 100;
sy1 = sy1 - (c->Cy1 * t) / 100;
sy2 = sy2 - (c->Cy2 * t) / 100;
/*
* Break y1 and y2 into y and z, y1 and y2 are apparently encoding
* y and z.
*/
sy = sy1 - sy2;
sz = -sy1 - sy2;
/*
* FIXME: convert to Celsius? Just guessing this is given
* as 1/10:s of degrees so multiply by 100 to get millicentigrades.
*/
*to = t * 100;
/*
* Calibrate [x,y,z] with some formulas like this:
*
* 100 * x + a_2 * y + a_3 * z
* x' = k * ---------------------------
* 10
*
* a_4 * x + a_5 * y + a_6 * z
* y' = k * ---------------------------
* 10
*
* a_7 * x + a_8 * y + a_9 * z
* z' = k * ---------------------------
* 10
*/
*xo = c->k * ((100 * sx + c->a2 * sy + c->a3 * sz) / 10);
*yo = c->k * ((c->a4 * sx + c->a5 * sy + c->a6 * sz) / 10);
*zo = c->k * ((c->a7 * sx + c->a8 * sy + c->a9 * sz) / 10);
return 0;
}
static int yas5xx_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2,
long mask)
{
struct yas5xx *yas5xx = iio_priv(indio_dev);
s32 t, x, y, z;
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
pm_runtime_get_sync(yas5xx->dev);
ret = yas5xx_get_measure(yas5xx, &t, &x, &y, &z);
pm_runtime_mark_last_busy(yas5xx->dev);
pm_runtime_put_autosuspend(yas5xx->dev);
if (ret)
return ret;
switch (chan->address) {
case 0:
*val = t;
break;
case 1:
*val = x;
break;
case 2:
*val = y;
break;
case 3:
*val = z;
break;
default:
dev_err(yas5xx->dev, "unknown channel\n");
return -EINVAL;
}
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if (chan->address == 0) {
/* Temperature is unscaled */
*val = 1;
return IIO_VAL_INT;
}
/*
* The axis values are in nanotesla according to the vendor
* drivers, but is clearly in microtesla according to
* experiments. Since 1 uT = 0.01 Gauss, we need to divide
* by 100000000 (10^8) to get to Gauss from the raw value.
*/
*val = 1;
*val2 = 100000000;
return IIO_VAL_FRACTIONAL;
default:
/* Unknown request */
return -EINVAL;
}
}
static void yas5xx_fill_buffer(struct iio_dev *indio_dev)
{
struct yas5xx *yas5xx = iio_priv(indio_dev);
s32 t, x, y, z;
int ret;
pm_runtime_get_sync(yas5xx->dev);
ret = yas5xx_get_measure(yas5xx, &t, &x, &y, &z);
pm_runtime_mark_last_busy(yas5xx->dev);
pm_runtime_put_autosuspend(yas5xx->dev);
if (ret) {
dev_err(yas5xx->dev, "error refilling buffer\n");
return;
}
yas5xx->scan.channels[0] = t;
yas5xx->scan.channels[1] = x;
yas5xx->scan.channels[2] = y;
yas5xx->scan.channels[3] = z;
iio_push_to_buffers_with_timestamp(indio_dev, &yas5xx->scan,
iio_get_time_ns(indio_dev));
}
static irqreturn_t yas5xx_handle_trigger(int irq, void *p)
{
const struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
yas5xx_fill_buffer(indio_dev);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static const struct iio_mount_matrix *
yas5xx_get_mount_matrix(const struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct yas5xx *yas5xx = iio_priv(indio_dev);
return &yas5xx->orientation;
}
static const struct iio_chan_spec_ext_info yas5xx_ext_info[] = {
IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, yas5xx_get_mount_matrix),
{ }
};
#define YAS5XX_AXIS_CHANNEL(axis, index) \
{ \
.type = IIO_MAGN, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_SCALE), \
.ext_info = yas5xx_ext_info, \
.address = index, \
.scan_index = index, \
.scan_type = { \
.sign = 's', \
.realbits = 32, \
.storagebits = 32, \
.endianness = IIO_CPU, \
}, \
}
static const struct iio_chan_spec yas5xx_channels[] = {
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
.address = 0,
.scan_index = 0,
.scan_type = {
.sign = 'u',
.realbits = 32,
.storagebits = 32,
.endianness = IIO_CPU,
},
},
YAS5XX_AXIS_CHANNEL(X, 1),
YAS5XX_AXIS_CHANNEL(Y, 2),
YAS5XX_AXIS_CHANNEL(Z, 3),
IIO_CHAN_SOFT_TIMESTAMP(4),
};
static const unsigned long yas5xx_scan_masks[] = { GENMASK(3, 0), 0 };
static const struct iio_info yas5xx_info = {
.read_raw = &yas5xx_read_raw,
};
static bool yas5xx_volatile_reg(struct device *dev, unsigned int reg)
{
return reg == YAS5XX_ACTUATE_INIT_COIL ||
reg == YAS5XX_MEASURE ||
(reg >= YAS5XX_MEASURE_DATA && reg <= YAS5XX_MEASURE_DATA + 8);
}
/* TODO: enable regmap cache, using mark dirty and sync at runtime resume */
static const struct regmap_config yas5xx_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0xff,
.volatile_reg = yas5xx_volatile_reg,
};
/**
* yas53x_extract_calibration() - extracts the a2-a9 and k calibration
* @data: the bitfield to use
* @c: the calibration to populate
*/
static void yas53x_extract_calibration(u8 *data, struct yas5xx_calibration *c)
{
u64 val = get_unaligned_be64(data);
/*
* Bitfield layout for the axis calibration data, for factor
* a2 = 2 etc, k = k, c = clock divider
*
* n 7 6 5 4 3 2 1 0
* 0 [ 2 2 2 2 2 2 3 3 ] bits 63 .. 56
* 1 [ 3 3 4 4 4 4 4 4 ] bits 55 .. 48
* 2 [ 5 5 5 5 5 5 6 6 ] bits 47 .. 40
* 3 [ 6 6 6 6 7 7 7 7 ] bits 39 .. 32
* 4 [ 7 7 7 8 8 8 8 8 ] bits 31 .. 24
* 5 [ 8 9 9 9 9 9 9 9 ] bits 23 .. 16
* 6 [ 9 k k k k k c c ] bits 15 .. 8
* 7 [ c x x x x x x x ] bits 7 .. 0
*/
c->a2 = FIELD_GET(GENMASK_ULL(63, 58), val) - 32;
c->a3 = FIELD_GET(GENMASK_ULL(57, 54), val) - 8;
c->a4 = FIELD_GET(GENMASK_ULL(53, 48), val) - 32;
c->a5 = FIELD_GET(GENMASK_ULL(47, 42), val) + 38;
c->a6 = FIELD_GET(GENMASK_ULL(41, 36), val) - 32;
c->a7 = FIELD_GET(GENMASK_ULL(35, 29), val) - 64;
c->a8 = FIELD_GET(GENMASK_ULL(28, 23), val) - 32;
c->a9 = FIELD_GET(GENMASK_ULL(22, 15), val);
c->k = FIELD_GET(GENMASK_ULL(14, 10), val) + 10;
c->dck = FIELD_GET(GENMASK_ULL(9, 7), val);
}
static int yas530_get_calibration_data(struct yas5xx *yas5xx)
{
struct yas5xx_calibration *c = &yas5xx->calibration;
u8 data[16];
u32 val;
int ret;
/* Dummy read, first read is ALWAYS wrong */
ret = regmap_bulk_read(yas5xx->map, YAS5XX_CAL, data, sizeof(data));
if (ret)
return ret;
/* Actual calibration readout */
ret = regmap_bulk_read(yas5xx->map, YAS5XX_CAL, data, sizeof(data));
if (ret)
return ret;
dev_dbg(yas5xx->dev, "calibration data: %*ph\n", 14, data);
add_device_randomness(data, sizeof(data));
yas5xx->version = data[15] & GENMASK(1, 0);
/* Extract the calibration from the bitfield */
c->Cx = data[0] * 6 - 768;
c->Cy1 = data[1] * 6 - 768;
c->Cy2 = data[2] * 6 - 768;
yas53x_extract_calibration(&data[3], c);
/*
* Extract linearization:
* Linearization layout in the 32 bits at byte 11:
* The r factors are 6 bit values where bit 5 is the sign
*
* n 7 6 5 4 3 2 1 0
* 0 [ xx xx xx r0 r0 r0 r0 r0 ] bits 31 .. 24
* 1 [ r0 f0 f0 r1 r1 r1 r1 r1 ] bits 23 .. 16
* 2 [ r1 f1 f1 r2 r2 r2 r2 r2 ] bits 15 .. 8
* 3 [ r2 f2 f2 xx xx xx xx xx ] bits 7 .. 0
*/
val = get_unaligned_be32(&data[11]);
c->f[0] = FIELD_GET(GENMASK(22, 21), val);
c->f[1] = FIELD_GET(GENMASK(14, 13), val);
c->f[2] = FIELD_GET(GENMASK(6, 5), val);
c->r[0] = sign_extend32(FIELD_GET(GENMASK(28, 23), val), 5);
c->r[1] = sign_extend32(FIELD_GET(GENMASK(20, 15), val), 5);
c->r[2] = sign_extend32(FIELD_GET(GENMASK(12, 7), val), 5);
return 0;
}
static int yas532_get_calibration_data(struct yas5xx *yas5xx)
{
struct yas5xx_calibration *c = &yas5xx->calibration;
u8 data[14];
u32 val;
int ret;
/* Dummy read, first read is ALWAYS wrong */
ret = regmap_bulk_read(yas5xx->map, YAS5XX_CAL, data, sizeof(data));
if (ret)
return ret;
/* Actual calibration readout */
ret = regmap_bulk_read(yas5xx->map, YAS5XX_CAL, data, sizeof(data));
if (ret)
return ret;
dev_dbg(yas5xx->dev, "calibration data: %*ph\n", 14, data);
/* Sanity check, is this all zeroes? */
if (memchr_inv(data, 0x00, 13) == NULL) {
if (!(data[13] & BIT(7)))
dev_warn(yas5xx->dev, "calibration is blank!\n");
}
add_device_randomness(data, sizeof(data));
/* Only one bit of version info reserved here as far as we know */
yas5xx->version = data[13] & BIT(0);
/* Extract calibration from the bitfield */
c->Cx = data[0] * 10 - 1280;
c->Cy1 = data[1] * 10 - 1280;
c->Cy2 = data[2] * 10 - 1280;
yas53x_extract_calibration(&data[3], c);
/*
* Extract linearization:
* Linearization layout in the 32 bits at byte 10:
* The r factors are 6 bit values where bit 5 is the sign
*
* n 7 6 5 4 3 2 1 0
* 0 [ xx r0 r0 r0 r0 r0 r0 f0 ] bits 31 .. 24
* 1 [ f0 r1 r1 r1 r1 r1 r1 f1 ] bits 23 .. 16
* 2 [ f1 r2 r2 r2 r2 r2 r2 f2 ] bits 15 .. 8
* 3 [ f2 xx xx xx xx xx xx xx ] bits 7 .. 0
*/
val = get_unaligned_be32(&data[10]);
c->f[0] = FIELD_GET(GENMASK(24, 23), val);
c->f[1] = FIELD_GET(GENMASK(16, 15), val);
c->f[2] = FIELD_GET(GENMASK(8, 7), val);
c->r[0] = sign_extend32(FIELD_GET(GENMASK(30, 25), val), 5);
c->r[1] = sign_extend32(FIELD_GET(GENMASK(22, 17), val), 5);
c->r[2] = sign_extend32(FIELD_GET(GENMASK(14, 7), val), 5);
return 0;
}
static void yas5xx_dump_calibration(struct yas5xx *yas5xx)
{
struct yas5xx_calibration *c = &yas5xx->calibration;
dev_dbg(yas5xx->dev, "f[] = [%d, %d, %d]\n",
c->f[0], c->f[1], c->f[2]);
dev_dbg(yas5xx->dev, "r[] = [%d, %d, %d]\n",
c->r[0], c->r[1], c->r[2]);
dev_dbg(yas5xx->dev, "Cx = %d\n", c->Cx);
dev_dbg(yas5xx->dev, "Cy1 = %d\n", c->Cy1);
dev_dbg(yas5xx->dev, "Cy2 = %d\n", c->Cy2);
dev_dbg(yas5xx->dev, "a2 = %d\n", c->a2);
dev_dbg(yas5xx->dev, "a3 = %d\n", c->a3);
dev_dbg(yas5xx->dev, "a4 = %d\n", c->a4);
dev_dbg(yas5xx->dev, "a5 = %d\n", c->a5);
dev_dbg(yas5xx->dev, "a6 = %d\n", c->a6);
dev_dbg(yas5xx->dev, "a7 = %d\n", c->a7);
dev_dbg(yas5xx->dev, "a8 = %d\n", c->a8);
dev_dbg(yas5xx->dev, "a9 = %d\n", c->a9);
dev_dbg(yas5xx->dev, "k = %d\n", c->k);
dev_dbg(yas5xx->dev, "dck = %d\n", c->dck);
}
static int yas5xx_set_offsets(struct yas5xx *yas5xx, s8 ox, s8 oy1, s8 oy2)
{
int ret;
ret = regmap_write(yas5xx->map, YAS5XX_OFFSET_X, ox);
if (ret)
return ret;
ret = regmap_write(yas5xx->map, YAS5XX_OFFSET_Y1, oy1);
if (ret)
return ret;
return regmap_write(yas5xx->map, YAS5XX_OFFSET_Y2, oy2);
}
static s8 yas5xx_adjust_offset(s8 old, int bit, u16 center, u16 measure)
{
if (measure > center)
return old + BIT(bit);
if (measure < center)
return old - BIT(bit);
return old;
}
static int yas5xx_meaure_offsets(struct yas5xx *yas5xx)
{
int ret;
u16 center;
u16 t, x, y1, y2;
s8 ox, oy1, oy2;
int i;
/* Actuate the init coil and measure offsets */
ret = regmap_write(yas5xx->map, YAS5XX_ACTUATE_INIT_COIL, 0);
if (ret)
return ret;
/* When the initcoil is active this should be around the center */
switch (yas5xx->devid) {
case YAS530_DEVICE_ID:
center = YAS530_DATA_CENTER;
break;
case YAS532_DEVICE_ID:
center = YAS532_DATA_CENTER;
break;
default:
dev_err(yas5xx->dev, "unknown device type\n");
return -EINVAL;
}
/*
* We set offsets in the interval +-31 by iterating
* +-16, +-8, +-4, +-2, +-1 adjusting the offsets each
* time, then writing the final offsets into the
* registers.
*
* NOTE: these offsets are NOT in the same unit or magnitude
* as the values for [x, y1, y2]. The value is +/-31
* but the effect on the raw values is much larger.
* The effect of the offset is to bring the measure
* rougly to the center.
*/
ox = 0;
oy1 = 0;
oy2 = 0;
for (i = 4; i >= 0; i--) {
ret = yas5xx_set_offsets(yas5xx, ox, oy1, oy2);
if (ret)
return ret;
ret = yas5xx_measure(yas5xx, &t, &x, &y1, &y2);
if (ret)
return ret;
dev_dbg(yas5xx->dev, "measurement %d: x=%d, y1=%d, y2=%d\n",
5-i, x, y1, y2);
ox = yas5xx_adjust_offset(ox, i, center, x);
oy1 = yas5xx_adjust_offset(oy1, i, center, y1);
oy2 = yas5xx_adjust_offset(oy2, i, center, y2);
}
/* Needed for calibration algorithm */
yas5xx->hard_offsets[0] = ox;
yas5xx->hard_offsets[1] = oy1;
yas5xx->hard_offsets[2] = oy2;
ret = yas5xx_set_offsets(yas5xx, ox, oy1, oy2);
if (ret)
return ret;
dev_info(yas5xx->dev, "discovered hard offsets: x=%d, y1=%d, y2=%d\n",
ox, oy1, oy2);
return 0;
}
static int yas5xx_power_on(struct yas5xx *yas5xx)
{
unsigned int val;
int ret;
/* Zero the test registers */
ret = regmap_write(yas5xx->map, YAS5XX_TEST1, 0);
if (ret)
return ret;
ret = regmap_write(yas5xx->map, YAS5XX_TEST2, 0);
if (ret)
return ret;
/* Set up for no interrupts, calibrated clock divider */
val = FIELD_PREP(YAS5XX_CONFIG_CCK_MASK, yas5xx->calibration.dck);
ret = regmap_write(yas5xx->map, YAS5XX_CONFIG, val);
if (ret)
return ret;
/* Measure interval 0 (back-to-back?) */
return regmap_write(yas5xx->map, YAS5XX_MEASURE_INTERVAL, 0);
}
static int yas5xx_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct iio_dev *indio_dev;
struct device *dev = &i2c->dev;
struct yas5xx *yas5xx;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*yas5xx));
if (!indio_dev)
return -ENOMEM;
yas5xx = iio_priv(indio_dev);
i2c_set_clientdata(i2c, indio_dev);
yas5xx->dev = dev;
mutex_init(&yas5xx->lock);
ret = iio_read_mount_matrix(dev, &yas5xx->orientation);
if (ret)
return ret;
yas5xx->regs[0].supply = "vdd";
yas5xx->regs[1].supply = "iovdd";
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(yas5xx->regs),
yas5xx->regs);
if (ret)
return dev_err_probe(dev, ret, "cannot get regulators\n");
ret = regulator_bulk_enable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
if (ret) {
dev_err(dev, "cannot enable regulators\n");
return ret;
}
/* See comment in runtime resume callback */
usleep_range(31000, 40000);
/* This will take the device out of reset if need be */
yas5xx->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(yas5xx->reset)) {
ret = dev_err_probe(dev, PTR_ERR(yas5xx->reset),
"failed to get reset line\n");
goto reg_off;
}
yas5xx->map = devm_regmap_init_i2c(i2c, &yas5xx_regmap_config);
if (IS_ERR(yas5xx->map)) {
dev_err(dev, "failed to allocate register map\n");
ret = PTR_ERR(yas5xx->map);
goto assert_reset;
}
ret = regmap_read(yas5xx->map, YAS5XX_DEVICE_ID, &yas5xx->devid);
if (ret)
goto assert_reset;
switch (yas5xx->devid) {
case YAS530_DEVICE_ID:
ret = yas530_get_calibration_data(yas5xx);
if (ret)
goto assert_reset;
dev_info(dev, "detected YAS530 MS-3E %s",
yas5xx->version ? "B" : "A");
strncpy(yas5xx->name, "yas530", sizeof(yas5xx->name));
break;
case YAS532_DEVICE_ID:
ret = yas532_get_calibration_data(yas5xx);
if (ret)
goto assert_reset;
dev_info(dev, "detected YAS532/YAS533 MS-3R/F %s",
yas5xx->version ? "AC" : "AB");
strncpy(yas5xx->name, "yas532", sizeof(yas5xx->name));
break;
default:
ret = -ENODEV;
dev_err(dev, "unhandled device ID %02x\n", yas5xx->devid);
goto assert_reset;
}
yas5xx_dump_calibration(yas5xx);
ret = yas5xx_power_on(yas5xx);
if (ret)
goto assert_reset;
ret = yas5xx_meaure_offsets(yas5xx);
if (ret)
goto assert_reset;
indio_dev->info = &yas5xx_info;
indio_dev->available_scan_masks = yas5xx_scan_masks;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->name = yas5xx->name;
indio_dev->channels = yas5xx_channels;
indio_dev->num_channels = ARRAY_SIZE(yas5xx_channels);
ret = iio_triggered_buffer_setup(indio_dev, NULL,
yas5xx_handle_trigger,
NULL);
if (ret) {
dev_err(dev, "triggered buffer setup failed\n");
goto assert_reset;
}
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(dev, "device register failed\n");
goto cleanup_buffer;
}
/* Take runtime PM online */
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
pm_runtime_set_autosuspend_delay(dev, YAS5XX_AUTOSUSPEND_DELAY_MS);
pm_runtime_use_autosuspend(dev);
pm_runtime_put(dev);
return 0;
cleanup_buffer:
iio_triggered_buffer_cleanup(indio_dev);
assert_reset:
gpiod_set_value_cansleep(yas5xx->reset, 1);
reg_off:
regulator_bulk_disable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
return ret;
}
static int yas5xx_remove(struct i2c_client *i2c)
{
struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
struct yas5xx *yas5xx = iio_priv(indio_dev);
struct device *dev = &i2c->dev;
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
/*
* Now we can't get any more reads from the device, which would
* also call pm_runtime* functions and race with our disable
* code. Disable PM runtime in orderly fashion and power down.
*/
pm_runtime_get_sync(dev);
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
gpiod_set_value_cansleep(yas5xx->reset, 1);
regulator_bulk_disable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
return 0;
}
static int yas5xx_runtime_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct yas5xx *yas5xx = iio_priv(indio_dev);
gpiod_set_value_cansleep(yas5xx->reset, 1);
regulator_bulk_disable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
return 0;
}
static int yas5xx_runtime_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct yas5xx *yas5xx = iio_priv(indio_dev);
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
if (ret) {
dev_err(dev, "cannot enable regulators\n");
return ret;
}
/*
* The YAS530 datasheet says TVSKW is up to 30 ms, after that 1 ms
* for all voltages to settle. The YAS532 is 10ms then 4ms for the
* I2C to come online. Let's keep it safe and put this at 31ms.
*/
usleep_range(31000, 40000);
gpiod_set_value_cansleep(yas5xx->reset, 0);
ret = yas5xx_power_on(yas5xx);
if (ret) {
dev_err(dev, "cannot power on\n");
goto out_reset;
}
return 0;
out_reset:
gpiod_set_value_cansleep(yas5xx->reset, 1);
regulator_bulk_disable(ARRAY_SIZE(yas5xx->regs), yas5xx->regs);
return ret;
}
static DEFINE_RUNTIME_DEV_PM_OPS(yas5xx_dev_pm_ops, yas5xx_runtime_suspend,
yas5xx_runtime_resume, NULL);
static const struct i2c_device_id yas5xx_id[] = {
{"yas530", },
{"yas532", },
{"yas533", },
{}
};
MODULE_DEVICE_TABLE(i2c, yas5xx_id);
static const struct of_device_id yas5xx_of_match[] = {
{ .compatible = "yamaha,yas530", },
{ .compatible = "yamaha,yas532", },
{ .compatible = "yamaha,yas533", },
{}
};
MODULE_DEVICE_TABLE(of, yas5xx_of_match);
static struct i2c_driver yas5xx_driver = {
.driver = {
.name = "yas5xx",
.of_match_table = yas5xx_of_match,
.pm = pm_ptr(&yas5xx_dev_pm_ops),
},
.probe = yas5xx_probe,
.remove = yas5xx_remove,
.id_table = yas5xx_id,
};
module_i2c_driver(yas5xx_driver);
MODULE_DESCRIPTION("Yamaha YAS53x 3-axis magnetometer driver");
MODULE_AUTHOR("Linus Walleij");
MODULE_LICENSE("GPL v2");