Add I2CXL-MaxSonar ultrasonic distance sensors of type family mb12x2 using
an i2c interface
Implemented functionality:
- reading the distance via in_distance_raw
- buffered mode with trigger
- make use of status gpio to announce completion of ranging
Add mb12x2 driver to Kconfig and Makefile
Signed-off-by: Andreas Klinger <a...@it-klinger.de>
---
drivers/iio/proximity/Kconfig | 11 ++
drivers/iio/proximity/Makefile | 1 +
drivers/iio/proximity/mb12x2.c | 283 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 295 insertions(+)
create mode 100644 drivers/iio/proximity/mb12x2.c
diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index b99367a89f81..a420f2cb314b 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -45,6 +45,17 @@ config LIDAR_LITE_V2
To compile this driver as a module, choose M here: the
module will be called pulsedlight-lite-v2
+config MB12X2
+ tristate "MaxSonar MB12X2 family ultrasonic sensors"
+ depends on I2C
+ help
+ Say Y to build a driver for the ultrasonic sensors I2CXL of
+ MaxBotix which have an i2c interface. It can be used to measure
+ the distance of objects.
+
+ To compile this driver as a module, choose M here: the
+ module will be called mb12x2.
+
config RFD77402
tristate "RFD77402 ToF sensor"
depends on I2C
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index 6d031f903c4c..be9a14db77e7 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -7,6 +7,7 @@
obj-$(CONFIG_AS3935) += as3935.o
obj-$(CONFIG_ISL29501) += isl29501.o
obj-$(CONFIG_LIDAR_LITE_V2) += pulsedlight-lidar-lite-v2.o
+obj-$(CONFIG_MB12X2) += mb12x2.o
obj-$(CONFIG_RFD77402) += rfd77402.o
obj-$(CONFIG_SRF04) += srf04.o
obj-$(CONFIG_SRF08) += srf08.o
diff --git a/drivers/iio/proximity/mb12x2.c b/drivers/iio/proximity/mb12x2.c
new file mode 100644
index 000000000000..8b1ac901c253
--- /dev/null
+++ b/drivers/iio/proximity/mb12x2.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * mb12x2.c - Support for MaxBotix I2CXL-MaxSonar-EZ series ultrasonic
+ * ranger with i2c interface
+ * actually supported are mb12x2 types
+ *
+ * Copyright (c) 2019 Andreas Klinger <a...@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/gpio/consumer.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 MB12X2_RANGE_COMMAND 0x51 /* Command for reading range */
+#define MB12X2_ADDR_UNLOCK_1 0xAA /* Command 1 for changing address */
+#define MB12X2_ADDR_UNLOCK_2 0xA5 /* Command 2 for changing address */
+
+struct mb12x2_data {
+ struct i2c_client *client;
+
+ struct mutex lock;
+
+ /*
+ * optionally a gpio can be used to announce when ranging has
+ * finished
+ */
+ struct completion ranging;
+ struct gpio_desc *gpiod_status;
+ int irqnr;
+
+ /*
+ * triggered buffer
+ * 1x16-bit channel + 3x16 padding + 4x16 timestamp
+ */
+ s16 buffer[8];
+};
+
+static irqreturn_t mb12x2_handle_irq(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct mb12x2_data *data = iio_priv(indio_dev);
+
+ /* double check to make sure data is now available */
+ if (!gpiod_get_value(data->gpiod_status))
+ complete(&data->ranging);
+
+ return IRQ_HANDLED;
+}
+
+static s16 mb12x2_read_distance(struct mb12x2_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, MB12X2_RANGE_COMMAND);
+ if (ret < 0) {
+ dev_err(&client->dev, "write command - err: %d\n", ret);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ if (data->gpiod_status) {
+ /* it cannot take more than 100 ms */
+ ret = wait_for_completion_killable_timeout(&data->ranging,
+ HZ/10);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ } else if (ret == 0) {
+ mutex_unlock(&data->lock);
+ return -ETIMEDOUT;
+ }
+ } else {
+ /*
+ * use simple sleep if gpio announce pin 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);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ distance = __be16_to_cpu(buf);
+ /* check for not returning misleading error codes */
+ if (distance < 0) {
+ dev_err(&client->dev, "distance=%d\n", distance);
+ return -EINVAL;
+ }
+
+ mutex_unlock(&data->lock);
+
+ return distance;
+}
+
+static irqreturn_t mb12x2_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct mb12x2_data *data = iio_priv(indio_dev);
+ s16 sensor_data;
+
+ sensor_data = mb12x2_read_distance(data);
+ if (sensor_data < 0)
+ goto err;
+
+ mutex_lock(&data->lock);
+
+ data->buffer[0] = sensor_data;
+ iio_push_to_buffers_with_timestamp(indio_dev,
+ data->buffer, pf->timestamp);
+
+ mutex_unlock(&data->lock);
+err:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+static int mb12x2_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val,
+ int *val2, long mask)
+{
+ struct mb12x2_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (channel->type != IIO_DISTANCE)
+ return -EINVAL;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = mb12x2_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 mb12x2_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 mb12x2_info = {
+ .read_raw = mb12x2_read_raw,
+};
+
+static int mb12x2_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct iio_dev *indio_dev;
+ struct mb12x2_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 = &mb12x2_info;
+ indio_dev->name = id->name;
+ indio_dev->dev.parent = dev;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = mb12x2_channels;
+ indio_dev->num_channels = ARRAY_SIZE(mb12x2_channels);
+
+ mutex_init(&data->lock);
+
+ init_completion(&data->ranging);
+
+ data->gpiod_status = devm_gpiod_get(dev, "status", GPIOD_IN);
+ if (IS_ERR(data->gpiod_status)) {
+ if (PTR_ERR(data->gpiod_status) == -ENOENT) {
+ dev_warn(dev, "no status gpio --> use sleep instead\n");
+ data->gpiod_status = NULL;
+ } else {
+ dev_err(dev, "cannot setup gpio; err=%ld\n",
+ PTR_ERR(data->gpiod_status));
+ return PTR_ERR(data->gpiod_status);
+ }
+ }
+
+ if (data->gpiod_status) {
+ data->irqnr = gpiod_to_irq(data->gpiod_status);
+ if (data->irqnr < 0) {
+ dev_err(dev, "gpiod_to_irq: %d\n", data->irqnr);
+ return data->irqnr;
+ }
+
+ ret = devm_request_irq(dev, data->irqnr, mb12x2_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, mb12x2_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_mb12x2_match[] = {
+ { .compatible = "maxbotix,i2cxl", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_mb12x2_match);
+
+static const struct i2c_device_id mb12x2_id[] = {
+ { "maxbotix-i2cxl", },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, mb12x2_id);
+
+static struct i2c_driver mb12x2_driver = {
+ .driver = {
+ .name = "maxbotix-i2cxl",
+ .of_match_table = of_mb12x2_match,
+ },
+ .probe = mb12x2_probe,
+ .id_table = mb12x2_id,
+};
+module_i2c_driver(mb12x2_driver);
+
+MODULE_AUTHOR("Andreas Klinger <a...@it-klinger.de>");
+MODULE_DESCRIPTION("Maxbotix I2CXL-MaxSonar i2c ultrasonic ranger driver");
+MODULE_LICENSE("GPL");
--
2.11.0
