drivers/iio/accel/bma220_spi.c - kernel/common - Git at Google

 // 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_DATA_SHIFT			2
 #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 = BMA220_DATA_SHIFT,				\
 		.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;
 	s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 8x8 timestamp */
 	u8 tx_buf[2] ____cacheline_aligned;
 };

 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->buffer,
 				  ARRAY_SIZE(bma220_channels) - 1);
 	if (ret < 0)
 		goto err;

 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 					   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 >> BMA220_DATA_SHIFT, 5);
 		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_deinit(struct spi_device *spi)
 {
 	int ret;

 	/* Make sure the chip is powered off */
 	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
 	if (ret == BMA220_SUSPEND_SLEEP)
 		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
 	if (ret < 0)
 		return ret;
 	if (ret == BMA220_SUSPEND_SLEEP)
 		return -EBUSY;

 	return 0;
 }

 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;
 	spi_set_drvdata(spi, indio_dev);
 	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 = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
 					 bma220_trigger_handler, NULL);
 	if (ret < 0) {
 		dev_err(&spi->dev, "iio triggered buffer setup failed\n");
 		goto err_suspend;
 	}

 	ret = iio_device_register(indio_dev);
 	if (ret < 0) {
 		dev_err(&spi->dev, "iio_device_register failed\n");
 		iio_triggered_buffer_cleanup(indio_dev);
 		goto err_suspend;
 	}

 	return 0;

 err_suspend:
 	return bma220_deinit(spi);
 }

 static int bma220_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);

 	iio_device_unregister(indio_dev);
 	iio_triggered_buffer_cleanup(indio_dev);

 	return bma220_deinit(spi);
 }

 static __maybe_unused int bma220_suspend(struct device *dev)
 {
 	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));

 	/* The chip can be suspended/woken up by a simple register read. */
 	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
 }

 static __maybe_unused int bma220_resume(struct device *dev)
 {
 	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));

 	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
 }
 static 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 = &bma220_pm_ops,
 		.acpi_match_table = bma220_acpi_id,
 	},
 	.probe =            bma220_probe,
 	.remove =           bma220_remove,
 	.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");
	// 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_DATA_SHIFT 2
	#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 = BMA220_DATA_SHIFT, \
	.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;
	s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 8x8 timestamp */
	u8 tx_buf[2] ____cacheline_aligned;
	};

	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->buffer,
	ARRAY_SIZE(bma220_channels) - 1);
	if (ret < 0)
	goto err;

	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
	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 >> BMA220_DATA_SHIFT, 5);
	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_deinit(struct spi_device *spi)
	{
	int ret;

	/* Make sure the chip is powered off */
	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
	if (ret == BMA220_SUSPEND_SLEEP)
	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
	if (ret < 0)
	return ret;
	if (ret == BMA220_SUSPEND_SLEEP)
	return -EBUSY;

	return 0;
	}

	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;
	spi_set_drvdata(spi, indio_dev);
	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 = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
	bma220_trigger_handler, NULL);
	if (ret < 0) {
	dev_err(&spi->dev, "iio triggered buffer setup failed\n");
	goto err_suspend;
	}

	ret = iio_device_register(indio_dev);
	if (ret < 0) {
	dev_err(&spi->dev, "iio_device_register failed\n");
	iio_triggered_buffer_cleanup(indio_dev);
	goto err_suspend;
	}

	return 0;

	err_suspend:
	return bma220_deinit(spi);
	}

	static int bma220_remove(struct spi_device *spi)
	{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);

	iio_device_unregister(indio_dev);
	iio_triggered_buffer_cleanup(indio_dev);

	return bma220_deinit(spi);
	}

	static __maybe_unused int bma220_suspend(struct device *dev)
	{
	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));

	/* The chip can be suspended/woken up by a simple register read. */
	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
	}

	static __maybe_unused int bma220_resume(struct device *dev)
	{
	struct bma220_data *data = iio_priv(dev_get_drvdata(dev));

	return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
	}
	static 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 = &bma220_pm_ops,
	.acpi_match_table = bma220_acpi_id,
	},
	.probe = bma220_probe,
	.remove = bma220_remove,
	.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");