273 lines
6.3 KiB
C
273 lines
6.3 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* mb1232.c - Support for MaxBotix I2CXL-MaxSonar-EZ series ultrasonic
|
|
* ranger with i2c interface
|
|
* actually tested with mb1232 type
|
|
*
|
|
* Copyright (c) 2019 Andreas Klinger <ak@it-klinger.de>
|
|
*
|
|
* For details about the device see:
|
|
* https://www.maxbotix.com/documents/I2CXL-MaxSonar-EZ_Datasheet.pdf
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/module.h>
|
|
#include <linux/bitops.h>
|
|
#include <linux/iio/iio.h>
|
|
#include <linux/iio/sysfs.h>
|
|
#include <linux/iio/buffer.h>
|
|
#include <linux/iio/trigger_consumer.h>
|
|
#include <linux/iio/triggered_buffer.h>
|
|
|
|
/* registers of MaxSonar device */
|
|
#define MB1232_RANGE_COMMAND 0x51 /* Command for reading range */
|
|
#define MB1232_ADDR_UNLOCK_1 0xAA /* Command 1 for changing address */
|
|
#define MB1232_ADDR_UNLOCK_2 0xA5 /* Command 2 for changing address */
|
|
|
|
struct mb1232_data {
|
|
struct i2c_client *client;
|
|
|
|
struct mutex lock;
|
|
|
|
/*
|
|
* optionally a gpio can be used to announce when ranging has
|
|
* finished
|
|
* since we are just using the falling trigger of it we request
|
|
* only the interrupt for announcing when data is ready to be read
|
|
*/
|
|
struct completion ranging;
|
|
int irqnr;
|
|
};
|
|
|
|
static irqreturn_t mb1232_handle_irq(int irq, void *dev_id)
|
|
{
|
|
struct iio_dev *indio_dev = dev_id;
|
|
struct mb1232_data *data = iio_priv(indio_dev);
|
|
|
|
complete(&data->ranging);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static s16 mb1232_read_distance(struct mb1232_data *data)
|
|
{
|
|
struct i2c_client *client = data->client;
|
|
int ret;
|
|
s16 distance;
|
|
__be16 buf;
|
|
|
|
mutex_lock(&data->lock);
|
|
|
|
reinit_completion(&data->ranging);
|
|
|
|
ret = i2c_smbus_write_byte(client, MB1232_RANGE_COMMAND);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "write command - err: %d\n", ret);
|
|
goto error_unlock;
|
|
}
|
|
|
|
if (data->irqnr >= 0) {
|
|
/* it cannot take more than 100 ms */
|
|
ret = wait_for_completion_killable_timeout(&data->ranging,
|
|
HZ/10);
|
|
if (ret < 0)
|
|
goto error_unlock;
|
|
else if (ret == 0) {
|
|
ret = -ETIMEDOUT;
|
|
goto error_unlock;
|
|
}
|
|
} else {
|
|
/* use simple sleep if announce irq is not connected */
|
|
msleep(15);
|
|
}
|
|
|
|
ret = i2c_master_recv(client, (char *)&buf, sizeof(buf));
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "i2c_master_recv: ret=%d\n", ret);
|
|
goto error_unlock;
|
|
}
|
|
|
|
distance = __be16_to_cpu(buf);
|
|
/* check for not returning misleading error codes */
|
|
if (distance < 0) {
|
|
dev_err(&client->dev, "distance=%d\n", distance);
|
|
ret = -EINVAL;
|
|
goto error_unlock;
|
|
}
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
return distance;
|
|
|
|
error_unlock:
|
|
mutex_unlock(&data->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static irqreturn_t mb1232_trigger_handler(int irq, void *p)
|
|
{
|
|
struct iio_poll_func *pf = p;
|
|
struct iio_dev *indio_dev = pf->indio_dev;
|
|
struct mb1232_data *data = iio_priv(indio_dev);
|
|
/*
|
|
* triggered buffer
|
|
* 16-bit channel + 48-bit padding + 64-bit timestamp
|
|
*/
|
|
s16 buffer[8] = { 0 };
|
|
|
|
buffer[0] = mb1232_read_distance(data);
|
|
if (buffer[0] < 0)
|
|
goto err;
|
|
|
|
iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
|
|
|
|
err:
|
|
iio_trigger_notify_done(indio_dev->trig);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int mb1232_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *channel, int *val,
|
|
int *val2, long mask)
|
|
{
|
|
struct mb1232_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
if (channel->type != IIO_DISTANCE)
|
|
return -EINVAL;
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_RAW:
|
|
ret = mb1232_read_distance(data);
|
|
if (ret < 0)
|
|
return ret;
|
|
*val = ret;
|
|
return IIO_VAL_INT;
|
|
case IIO_CHAN_INFO_SCALE:
|
|
/* 1 LSB is 1 cm */
|
|
*val = 0;
|
|
*val2 = 10000;
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static const struct iio_chan_spec mb1232_channels[] = {
|
|
{
|
|
.type = IIO_DISTANCE,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
|
|
BIT(IIO_CHAN_INFO_SCALE),
|
|
.scan_index = 0,
|
|
.scan_type = {
|
|
.sign = 's',
|
|
.realbits = 16,
|
|
.storagebits = 16,
|
|
.endianness = IIO_CPU,
|
|
},
|
|
},
|
|
IIO_CHAN_SOFT_TIMESTAMP(1),
|
|
};
|
|
|
|
static const struct iio_info mb1232_info = {
|
|
.read_raw = mb1232_read_raw,
|
|
};
|
|
|
|
static int mb1232_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct iio_dev *indio_dev;
|
|
struct mb1232_data *data;
|
|
int ret;
|
|
struct device *dev = &client->dev;
|
|
|
|
if (!i2c_check_functionality(client->adapter,
|
|
I2C_FUNC_SMBUS_READ_BYTE |
|
|
I2C_FUNC_SMBUS_WRITE_BYTE))
|
|
return -ENODEV;
|
|
|
|
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
|
|
if (!indio_dev)
|
|
return -ENOMEM;
|
|
|
|
data = iio_priv(indio_dev);
|
|
i2c_set_clientdata(client, indio_dev);
|
|
data->client = client;
|
|
|
|
indio_dev->info = &mb1232_info;
|
|
indio_dev->name = id->name;
|
|
indio_dev->dev.parent = dev;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->channels = mb1232_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(mb1232_channels);
|
|
|
|
mutex_init(&data->lock);
|
|
|
|
init_completion(&data->ranging);
|
|
|
|
data->irqnr = irq_of_parse_and_map(dev->of_node, 0);
|
|
if (data->irqnr <= 0) {
|
|
/* usage of interrupt is optional */
|
|
data->irqnr = -1;
|
|
} else {
|
|
ret = devm_request_irq(dev, data->irqnr, mb1232_handle_irq,
|
|
IRQF_TRIGGER_FALLING, id->name, indio_dev);
|
|
if (ret < 0) {
|
|
dev_err(dev, "request_irq: %d\n", ret);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
|
|
iio_pollfunc_store_time, mb1232_trigger_handler, NULL);
|
|
if (ret < 0) {
|
|
dev_err(dev, "setup of iio triggered buffer failed\n");
|
|
return ret;
|
|
}
|
|
|
|
return devm_iio_device_register(dev, indio_dev);
|
|
}
|
|
|
|
static const struct of_device_id of_mb1232_match[] = {
|
|
{ .compatible = "maxbotix,mb1202", },
|
|
{ .compatible = "maxbotix,mb1212", },
|
|
{ .compatible = "maxbotix,mb1222", },
|
|
{ .compatible = "maxbotix,mb1232", },
|
|
{ .compatible = "maxbotix,mb1242", },
|
|
{ .compatible = "maxbotix,mb7040", },
|
|
{ .compatible = "maxbotix,mb7137", },
|
|
{},
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, of_mb1232_match);
|
|
|
|
static const struct i2c_device_id mb1232_id[] = {
|
|
{ "maxbotix-mb1202", },
|
|
{ "maxbotix-mb1212", },
|
|
{ "maxbotix-mb1222", },
|
|
{ "maxbotix-mb1232", },
|
|
{ "maxbotix-mb1242", },
|
|
{ "maxbotix-mb7040", },
|
|
{ "maxbotix-mb7137", },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, mb1232_id);
|
|
|
|
static struct i2c_driver mb1232_driver = {
|
|
.driver = {
|
|
.name = "maxbotix-mb1232",
|
|
.of_match_table = of_mb1232_match,
|
|
},
|
|
.probe = mb1232_probe,
|
|
.id_table = mb1232_id,
|
|
};
|
|
module_i2c_driver(mb1232_driver);
|
|
|
|
MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
|
|
MODULE_DESCRIPTION("Maxbotix I2CXL-MaxSonar i2c ultrasonic ranger driver");
|
|
MODULE_LICENSE("GPL");
|