// SPDX-License-Identifier: GPL-2.0-only
/*
* BMA220 Digital triaxial acceleration sensor driver
*
* Copyright (c) 2016,2020 Intel Corporation.
*/
#include <linux/bits.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define BMA220_REG_ID 0x00
#define BMA220_REG_ACCEL_X 0x02
#define BMA220_REG_ACCEL_Y 0x03
#define BMA220_REG_ACCEL_Z 0x04
#define BMA220_REG_RANGE 0x11
#define BMA220_REG_SUSPEND 0x18
#define BMA220_CHIP_ID 0xDD
#define BMA220_READ_MASK BIT(7)
#define BMA220_RANGE_MASK GENMASK(1, 0)
#define BMA220_SUSPEND_SLEEP 0xFF
#define BMA220_SUSPEND_WAKE 0x00
#define BMA220_DEVICE_NAME "bma220"
#define BMA220_ACCEL_CHANNEL(index, reg, axis) { \
.type = IIO_ACCEL, \
.address = reg, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = index, \
.scan_type = { \
.sign = 's', \
.realbits = 6, \
.storagebits = 8, \
.shift = 2, \
.endianness = IIO_CPU, \
}, \
}
enum bma220_axis {
AXIS_X,
AXIS_Y,
AXIS_Z,
};
static const int bma220_scale_table[][2] = {
{0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},
};
struct bma220_data {
struct spi_device *spi_device;
struct mutex lock;
struct {
s8 chans[3];
/* Ensure timestamp is naturally aligned. */
s64 timestamp __aligned(8);
} scan;
u8 tx_buf[2] __aligned(IIO_DMA_MINALIGN);
};
static const struct iio_chan_spec bma220_channels[] = {
BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
{
return spi_w8r8(spi, reg | BMA220_READ_MASK);
}
static const unsigned long bma220_accel_scan_masks[] = {
BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
0
};
static irqreturn_t bma220_trigger_handler(int irq, void *p)
{
int ret;
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct bma220_data *data = iio_priv(indio_dev);
struct spi_device *spi = data->spi_device;
mutex_lock(&data->lock);
data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
ARRAY_SIZE(bma220_channels) - 1);
if (ret < 0)
goto err;
iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
pf->timestamp);
err:
mutex_unlock(&data->lock);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int bma220_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret;
u8 range_idx;
struct bma220_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = bma220_read_reg(data->spi_device, chan->address);
if (ret < 0)
return -EINVAL;
*val = sign_extend32(ret >> chan->scan_type.shift,
chan->scan_type.realbits - 1);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
if (ret < 0)
return ret;
range_idx = ret & BMA220_RANGE_MASK;
*val = bma220_scale_table[range_idx][0];
*val2 = bma220_scale_table[range_idx][1];
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int bma220_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
int i;
int ret;
int index = -1;
struct bma220_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_SCALE:
for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
if (val == bma220_scale_table[i][0] &&
val2 == bma220_scale_table[i][1]) {
index = i;
break;
}
if (index < 0)
return -EINVAL;
mutex_lock(&data->lock);
data->tx_buf[0] = BMA220_REG_RANGE;
data->tx_buf[1] = index;
ret = spi_write(data->spi_device, data->tx_buf,
sizeof(data->tx_buf));
if (ret < 0)
dev_err(&data->spi_device->dev,
"failed to set measurement range\n");
mutex_unlock(&data->lock);
return 0;
}
return -EINVAL;
}
static int bma220_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_SCALE:
*vals = (int *)bma220_scale_table;
*type = IIO_VAL_INT_PLUS_MICRO;
*length = ARRAY_SIZE(bma220_scale_table) * 2;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static const struct iio_info bma220_info = {
.read_raw = bma220_read_raw,
.write_raw = bma220_write_raw,
.read_avail = bma220_read_avail,
};
static int bma220_init(struct spi_device *spi)
{
int ret;
ret = bma220_read_reg(spi, BMA220_REG_ID);
if (ret != BMA220_CHIP_ID)
return -ENODEV;
/* Make sure the chip is powered on */
ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
if (ret == BMA220_SUSPEND_WAKE)
ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
if (ret < 0)
return ret;
if (ret == BMA220_SUSPEND_WAKE)
return -EBUSY;
return 0;
}
static int bma220_power(struct spi_device *spi, bool up)
{
int i, ret;
/**
* The chip can be suspended/woken up by a simple register read.
* So, we need up to 2 register reads of the suspend register
* to make sure that the device is in the desired state.
*/
for (i = 0; i < 2; i++) {
ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
if (ret < 0)
return ret;
if (up && ret == BMA220_SUSPEND_SLEEP)
return 0;
if (!up && ret == BMA220_SUSPEND_WAKE)
return 0;
}
return -EBUSY;
}
static void bma220_deinit(void *spi)
{
bma220_power(spi, false);
}
static int bma220_probe(struct spi_device *spi)
{
int ret;
struct iio_dev *indio_dev;
struct bma220_data *data;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
if (!indio_dev) {
dev_err(&spi->dev, "iio allocation failed!\n");
return -ENOMEM;
}
data = iio_priv(indio_dev);
data->spi_device = spi;
mutex_init(&data->lock);
indio_dev->info = &bma220_info;
indio_dev->name = BMA220_DEVICE_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = bma220_channels;
indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
indio_dev->available_scan_masks = bma220_accel_scan_masks;
ret = bma220_init(data->spi_device);
if (ret)
return ret;
ret = devm_add_action_or_reset(&spi->dev, bma220_deinit, spi);
if (ret)
return ret;
ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
iio_pollfunc_store_time,
bma220_trigger_handler, NULL);
if (ret < 0) {
dev_err(&spi->dev, "iio triggered buffer setup failed\n");
return ret;
}
return devm_iio_device_register(&spi->dev, indio_dev);
}
static int bma220_suspend(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
return bma220_power(spi, false);
}
static int bma220_resume(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
return bma220_power(spi, true);
}
static DEFINE_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
static const struct spi_device_id bma220_spi_id[] = {
{"bma220", 0},
{}
};
static const struct acpi_device_id bma220_acpi_id[] = {
{"BMA0220", 0},
{}
};
MODULE_DEVICE_TABLE(spi, bma220_spi_id);
static struct spi_driver bma220_driver = {
.driver = {
.name = "bma220_spi",
.pm = pm_sleep_ptr(&bma220_pm_ops),
.acpi_match_table = bma220_acpi_id,
},
.probe = bma220_probe,
.id_table = bma220_spi_id,
};
module_spi_driver(bma220_driver);
MODULE_AUTHOR("Tiberiu Breana <[email protected]>");
MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
MODULE_LICENSE("GPL v2");
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