--- /dev/null
+/*
+ * ADXRS450 Digital Output Gyroscope Driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/list.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "gyro.h"
+#include "../adc/adc.h"
+
+#include "adxrs450.h"
+
+/**
+ * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
+ * @dev: device associated with child of actual iio_dev
+ * @reg_address: the address of the lower of the two registers,which should be an even address,
+ * Second register's address is reg_address + 1.
+ * @val: somewhere to pass back the value read
+ **/
+static int adxrs450_spi_read_reg_16(struct device *dev,
+ u8 reg_address,
+ u16 *val)
+{
+ struct spi_message msg;
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct adxrs450_state *st = iio_dev_get_devdata(indio_dev);
+ int ret;
+ struct spi_transfer xfers = {
+ .tx_buf = st->tx,
+ .rx_buf = st->rx,
+ .bits_per_word = 8,
+ .len = 4,
+ };
+ /* Needs to send the command twice to get the wanted value */
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_READ_DATA | reg_address >> 7;
+ st->tx[1] = reg_address << 1;
+ st->tx[2] = 0;
+ st->tx[3] = 0;
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret) {
+ dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
+ reg_address);
+ goto error_ret;
+ }
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret) {
+ dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
+ reg_address);
+ goto error_ret;
+ }
+
+ *val = (st->rx[1] & 0x1f) << 11 | st->rx[2] << 3 | (st->rx[3] & 0xe0) >> 5;
+
+error_ret:
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+/**
+ * adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
+ * @dev: device associated with child of actual actual iio_dev
+ * @reg_address: the address of the lower of the two registers,which should be an even address,
+ * Second register's address is reg_address + 1.
+ * @val: value to be written.
+ **/
+static int adxrs450_spi_write_reg_16(struct device *dev,
+ u8 reg_address,
+ u16 val)
+{
+ struct spi_message msg;
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct adxrs450_state *st = iio_dev_get_devdata(indio_dev);
+ int ret;
+ struct spi_transfer xfers = {
+ .tx_buf = st->tx,
+ .rx_buf = st->rx,
+ .bits_per_word = 8,
+ .len = 4,
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_WRITE_DATA | reg_address >> 7;
+ st->tx[1] = reg_address << 1 | val >> 15;
+ st->tx[2] = val >> 7;
+ st->tx[3] = val << 1;
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret)
+ dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
+ reg_address);
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+/**
+ * adxrs450_spi_sensor_data() - read 2 bytes sensor data
+ * @dev: device associated with child of actual iio_dev
+ * @val: somewhere to pass back the value read
+ **/
+static int adxrs450_spi_sensor_data(struct device *dev, u16 *val)
+{
+ struct spi_message msg;
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct adxrs450_state *st = iio_dev_get_devdata(indio_dev);
+ int ret;
+ struct spi_transfer xfers = {
+ .tx_buf = st->tx,
+ .rx_buf = st->rx,
+ .bits_per_word = 8,
+ .len = 4,
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_SENSOR_DATA;
+ st->tx[1] = 0;
+ st->tx[2] = 0;
+ st->tx[3] = 0;
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret) {
+ dev_err(&st->us->dev, "Problem while reading sensor data\n");
+ goto error_ret;
+ }
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret) {
+ dev_err(&st->us->dev, "Problem while reading sensor data\n");
+ goto error_ret;
+ }
+
+ *val = (st->rx[0] & 0x03) << 14 | st->rx[1] << 6 | (st->rx[2] & 0xfc) >> 2;
+error_ret:
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+/**
+ * adxrs450_spi_initial() - use for initializing procedure.
+ * @st: device instance specific data
+ * @val: somewhere to pass back the value read
+ **/
+static int adxrs450_spi_initial(struct adxrs450_state *st,
+ u32 *val, char chk)
+{
+ struct spi_message msg;
+ int ret;
+ struct spi_transfer xfers = {
+ .tx_buf = st->tx,
+ .rx_buf = st->rx,
+ .bits_per_word = 8,
+ .len = 4,
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_SENSOR_DATA;
+ st->tx[1] = 0;
+ st->tx[2] = 0;
+ st->tx[3] = 0;
+ if (chk)
+ st->tx[3] |= (ADXRS450_CHK | ADXRS450_P);
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers, &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret) {
+ dev_err(&st->us->dev, "Problem while reading initializing data\n");
+ goto error_ret;
+ }
+
+ *val = be32_to_cpu(*(u32 *)st->rx);
+
+error_ret:
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+static ssize_t adxrs450_read_temp(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_TEMP1,
+ &t);
+ if (ret)
+ return ret;
+ return sprintf(buf, "%d\n", t);
+}
+
+static ssize_t adxrs450_read_quad(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_QUAD1,
+ &t);
+ if (ret)
+ return ret;
+ return sprintf(buf, "%d\n", t);
+}
+
+static ssize_t adxrs450_write_dnc(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ int ret;
+ long val;
+
+ ret = strict_strtol(buf, 10, &val);
+ if (ret)
+ goto error_ret;
+ ret = adxrs450_spi_write_reg_16(dev,
+ ADXRS450_DNC1,
+ val);
+error_ret:
+ return ret ? ret : len;
+}
+
+static ssize_t adxrs450_read_sensor_data(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret;
+ u16 t;
+
+ ret = adxrs450_spi_sensor_data(dev, &t);
+ if (ret)
+ return ret;
+
+ return sprintf(buf, "%d\n", t);
+}
+
+/* Recommended Startup Sequence by spec */
+static int adxrs450_initial_setup(struct adxrs450_state *st)
+{
+ u32 t;
+ u16 data;
+ int ret;
+ struct device *dev = &st->indio_dev->dev;
+
+ msleep(ADXRS450_STARTUP_DELAY*2);
+ ret = adxrs450_spi_initial(st, &t, 1);
+ if (ret)
+ return ret;
+ if (t != 0x01) {
+ dev_err(&st->us->dev, "The initial response is not correct!\n");
+ return -ENODEV;
+
+ }
+
+ msleep(ADXRS450_STARTUP_DELAY);
+ ret = adxrs450_spi_initial(st, &t, 0);
+ if (ret)
+ return ret;
+
+ msleep(ADXRS450_STARTUP_DELAY);
+ ret = adxrs450_spi_initial(st, &t, 0);
+ if (ret)
+ return ret;
+ if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
+ dev_err(&st->us->dev, "The second response is not correct!\n");
+ return -EIO;
+
+ }
+ ret = adxrs450_spi_initial(st, &t, 0);
+ if (ret)
+ return ret;
+ if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
+ dev_err(&st->us->dev, "The third response is not correct!\n");
+ return -EIO;
+
+ }
+ ret = adxrs450_spi_read_reg_16(dev, ADXRS450_FAULT1, &data);
+ if (ret)
+ return ret;
+ if (data & 0x0fff) {
+ dev_err(&st->us->dev, "The device is not in normal status!\n");
+ return -EINVAL;
+ }
+ ret = adxrs450_spi_read_reg_16(dev, ADXRS450_PID1, &data);
+ if (ret)
+ return ret;
+ dev_info(&st->us->dev, "The Part ID is 0x%x\n", data);
+
+ ret = adxrs450_spi_read_reg_16(dev, ADXRS450_SNL, &data);
+ if (ret)
+ return ret;
+ t = data;
+ ret = adxrs450_spi_read_reg_16(dev, ADXRS450_SNH, &data);
+ if (ret)
+ return ret;
+ t |= data << 16;
+ dev_info(&st->us->dev, "The Serial Number is 0x%x\n", t);
+
+ return 0;
+}
+
+static IIO_DEV_ATTR_GYRO_Z(adxrs450_read_sensor_data, 0);
+static IIO_DEV_ATTR_TEMP_RAW(adxrs450_read_temp);
+static IIO_DEV_ATTR_GYRO_Z_QUADRATURE_CORRECTION(adxrs450_read_quad, 0);
+static IIO_DEV_ATTR_GYRO_Z_CALIBBIAS(S_IWUSR,
+ NULL, adxrs450_write_dnc, 0);
+static IIO_CONST_ATTR(name, "adxrs450");
+
+static struct attribute *adxrs450_attributes[] = {
+ &iio_dev_attr_gyro_z_raw.dev_attr.attr,
+ &iio_dev_attr_temp_raw.dev_attr.attr,
+ &iio_dev_attr_gyro_z_quadrature_correction_raw.dev_attr.attr,
+ &iio_dev_attr_gyro_z_calibbias.dev_attr.attr,
+ &iio_const_attr_name.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group adxrs450_attribute_group = {
+ .attrs = adxrs450_attributes,
+};
+
+static int __devinit adxrs450_probe(struct spi_device *spi)
+{
+ int ret, regdone = 0;
+ struct adxrs450_state *st = kzalloc(sizeof *st, GFP_KERNEL);
+ if (!st) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ /* This is only used for removal purposes */
+ spi_set_drvdata(spi, st);
+
+ /* Allocate the comms buffers */
+ st->rx = kzalloc(sizeof(*st->rx)*ADXRS450_MAX_RX, GFP_KERNEL);
+ if (st->rx == NULL) {
+ ret = -ENOMEM;
+ goto error_free_st;
+ }
+ st->tx = kzalloc(sizeof(*st->tx)*ADXRS450_MAX_TX, GFP_KERNEL);
+ if (st->tx == NULL) {
+ ret = -ENOMEM;
+ goto error_free_rx;
+ }
+ st->us = spi;
+ mutex_init(&st->buf_lock);
+ /* setup the industrialio driver allocated elements */
+ st->indio_dev = iio_allocate_device();
+ if (st->indio_dev == NULL) {
+ ret = -ENOMEM;
+ goto error_free_tx;
+ }
+
+ st->indio_dev->dev.parent = &spi->dev;
+ st->indio_dev->attrs = &adxrs450_attribute_group;
+ st->indio_dev->dev_data = (void *)(st);
+ st->indio_dev->driver_module = THIS_MODULE;
+ st->indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = iio_device_register(st->indio_dev);
+ if (ret)
+ goto error_free_dev;
+ regdone = 1;
+
+ /* Get the device into a sane initial state */
+ ret = adxrs450_initial_setup(st);
+ if (ret)
+ goto error_initial;
+ return 0;
+
+error_initial:
+error_free_dev:
+ if (regdone)
+ iio_device_unregister(st->indio_dev);
+ else
+ iio_free_device(st->indio_dev);
+error_free_tx:
+ kfree(st->tx);
+error_free_rx:
+ kfree(st->rx);
+error_free_st:
+ kfree(st);
+error_ret:
+ return ret;
+}
+
+static int adxrs450_remove(struct spi_device *spi)
+{
+ struct adxrs450_state *st = spi_get_drvdata(spi);
+
+ iio_device_unregister(st->indio_dev);
+ kfree(st->tx);
+ kfree(st->rx);
+ kfree(st);
+
+ return 0;
+}
+
+static struct spi_driver adxrs450_driver = {
+ .driver = {
+ .name = "adxrs450",
+ .owner = THIS_MODULE,
+ },
+ .probe = adxrs450_probe,
+ .remove = __devexit_p(adxrs450_remove),
+};
+
+static __init int adxrs450_init(void)
+{
+ return spi_register_driver(&adxrs450_driver);
+}
+module_init(adxrs450_init);
+
+static __exit void adxrs450_exit(void)
+{
+ spi_unregister_driver(&adxrs450_driver);
+}
+module_exit(adxrs450_exit);
+
+MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices ADXRS450 Gyroscope SPI driver");
+MODULE_LICENSE("GPL v2");
git.openpandora.org / pandora-kernel.git / commitdiff