--- /dev/null
+/*
+ * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/mutex.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+
+#define ADIS16130_CON 0x0
+#define ADIS16130_CON_RD (1 << 6)
+#define ADIS16130_IOP 0x1
+
+/* 1 = data-ready signal low when unread data on all channels; */
+#define ADIS16130_IOP_ALL_RDY (1 << 3)
+#define ADIS16130_IOP_SYNC (1 << 0) /* 1 = synchronization enabled */
+#define ADIS16130_RATEDATA 0x8 /* Gyroscope output, rate of rotation */
+#define ADIS16130_TEMPDATA 0xA /* Temperature output */
+#define ADIS16130_RATECS 0x28 /* Gyroscope channel setup */
+#define ADIS16130_RATECS_EN (1 << 3) /* 1 = channel enable; */
+#define ADIS16130_TEMPCS 0x2A /* Temperature channel setup */
+#define ADIS16130_TEMPCS_EN (1 << 3)
+#define ADIS16130_RATECONV 0x30
+#define ADIS16130_TEMPCONV 0x32
+#define ADIS16130_MODE 0x38
+#define ADIS16130_MODE_24BIT (1 << 1) /* 1 = 24-bit resolution; */
+
+/**
+ * struct adis16130_state - device instance specific data
+ * @us: actual spi_device to write data
+ * @buf_lock: mutex to protect tx and rx
+ * @buf: unified tx/rx buffer
+ **/
+struct adis16130_state {
+ struct spi_device *us;
+ struct mutex buf_lock;
+ u8 buf[4] ____cacheline_aligned;
+};
+
+static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val)
+{
+ int ret;
+ struct adis16130_state *st = iio_priv(indio_dev);
+ struct spi_transfer xfer = {
+ .tx_buf = st->buf,
+ .rx_buf = st->buf,
+ .len = 4,
+ };
+
+ mutex_lock(&st->buf_lock);
+
+ st->buf[0] = ADIS16130_CON_RD | reg_addr;
+ st->buf[1] = st->buf[2] = st->buf[3] = 0;
+
+ ret = spi_sync_transfer(st->us, &xfer, 1);
+ if (ret == 0)
+ *val = (st->buf[1] << 16) | (st->buf[2] << 8) | st->buf[3];
+ mutex_unlock(&st->buf_lock);
+
+ return ret;
+}
+
+static int adis16130_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2,
+ long mask)
+{
+ int ret;
+ u32 temp;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ /* Take the iio_dev status lock */
+ mutex_lock(&indio_dev->mlock);
+ ret = adis16130_spi_read(indio_dev, chan->address, &temp);
+ mutex_unlock(&indio_dev->mlock);
+ if (ret)
+ return ret;
+ *val = temp;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_ANGL_VEL:
+ /* 0 degree = 838860, 250 degree = 14260608 */
+ *val = 250;
+ *val2 = 336440817; /* RAD_TO_DEGREE(14260608 - 8388608) */
+ return IIO_VAL_FRACTIONAL;
+ case IIO_TEMP:
+ /* 0C = 8036283, 105C = 9516048 */
+ *val = 105000;
+ *val2 = 9516048 - 8036283;
+ return IIO_VAL_FRACTIONAL;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_OFFSET:
+ switch (chan->type) {
+ case IIO_ANGL_VEL:
+ *val = -8388608;
+ return IIO_VAL_INT;
+ case IIO_TEMP:
+ *val = -8036283;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_chan_spec adis16130_channels[] = {
+ {
+ .type = IIO_ANGL_VEL,
+ .modified = 1,
+ .channel2 = IIO_MOD_Z,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .address = ADIS16130_RATEDATA,
+ }, {
+ .type = IIO_TEMP,
+ .indexed = 1,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .address = ADIS16130_TEMPDATA,
+ }
+};
+
+static const struct iio_info adis16130_info = {
+ .read_raw = &adis16130_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int adis16130_probe(struct spi_device *spi)
+{
+ struct adis16130_state *st;
+ struct iio_dev *indio_dev;
+
+ /* setup the industrialio driver allocated elements */
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+ st = iio_priv(indio_dev);
+ /* this is only used for removal purposes */
+ spi_set_drvdata(spi, indio_dev);
+ st->us = spi;
+ mutex_init(&st->buf_lock);
+ indio_dev->name = spi->dev.driver->name;
+ indio_dev->channels = adis16130_channels;
+ indio_dev->num_channels = ARRAY_SIZE(adis16130_channels);
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->info = &adis16130_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static struct spi_driver adis16130_driver = {
+ .driver = {
+ .name = "adis16130",
+ .owner = THIS_MODULE,
+ },
+ .probe = adis16130_probe,
+};
+module_spi_driver(adis16130_driver);
+
+MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("spi:adis16130");
Code Review / kvmfornfv.git / blobdiff