IIO: GYRO: IIO driver for Analog Devices Digital Output Gyroscope ADXRS450
authorMichael Hennerich <michael.hennerich@analog.com>
Wed, 6 Apr 2011 09:42:49 +0000 (11:42 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Wed, 20 Apr 2011 21:20:46 +0000 (14:20 -0700)
From: Cliff Cai <cliff.cai@analog.com>

Add new IIO driver for Analog Devices digital output gyroscope ADXRS450

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/staging/iio/gyro/Kconfig
drivers/staging/iio/gyro/Makefile
drivers/staging/iio/gyro/adxrs450.h [new file with mode: 0644]
drivers/staging/iio/gyro/adxrs450_core.c [new file with mode: 0644]

index 8b78fa0e63162a3080d0ff2d5b8357c7ddcf79f6..ae2e7d3095ae98fedea58a5bf6d763c7388eb516 100644 (file)
@@ -35,3 +35,13 @@ config ADIS16260
 
          This driver can also be built as a module.  If so, the module
          will be called adis16260.
+
+config ADXRS450
+       tristate "Analog Devices ADXRS450 Digital Output Gyroscope SPI driver"
+       depends on SPI
+       help
+         Say yes here to build support for Analog Devices ADXRS450 programmable
+         digital output gyroscope.
+
+         This driver can also be built as a module.  If so, the module
+         will be called adxrs450.
index 2764c15025a512ff07884f9a1c2f070b23286420..2212240f7de3035d9f7ba336d1ee60a6aa9e8962 100644 (file)
@@ -17,3 +17,6 @@ obj-$(CONFIG_ADIS16260) += adis16260.o
 
 adis16251-y             := adis16251_core.o
 obj-$(CONFIG_ADIS16251) += adis16251.o
+
+adxrs450-y             := adxrs450_core.o
+obj-$(CONFIG_ADXRS450) += adxrs450.o
diff --git a/drivers/staging/iio/gyro/adxrs450.h b/drivers/staging/iio/gyro/adxrs450.h
new file mode 100644 (file)
index 0000000..c92f694
--- /dev/null
@@ -0,0 +1,58 @@
+#ifndef SPI_ADXRS450_H_
+#define SPI_ADXRS450_H_
+
+#define ADXRS450_STARTUP_DELAY 50 /* ms */
+
+/* The MSB for the spi commands */
+#define ADXRS450_SENSOR_DATA    0x20
+#define ADXRS450_WRITE_DATA    0x40
+#define ADXRS450_READ_DATA     0x80
+
+#define ADXRS450_RATE1 0x00    /* Rate Registers */
+#define ADXRS450_TEMP1 0x02    /* Temperature Registers */
+#define ADXRS450_LOCST1        0x04    /* Low CST Memory Registers */
+#define ADXRS450_HICST1        0x06    /* High CST Memory Registers */
+#define ADXRS450_QUAD1 0x08    /* Quad Memory Registers */
+#define ADXRS450_FAULT1        0x0A    /* Fault Registers */
+#define ADXRS450_PID1  0x0C    /* Part ID Register 1 */
+#define ADXRS450_SNH   0x0E    /* Serial Number Registers, 4 bytes */
+#define ADXRS450_SNL   0x10
+#define ADXRS450_DNC1  0x12    /* Dynamic Null Correction Registers */
+/* Check bits */
+#define ADXRS450_P     0x01
+#define ADXRS450_CHK   0x02
+#define ADXRS450_CST   0x04
+#define ADXRS450_PWR   0x08
+#define ADXRS450_POR   0x10
+#define ADXRS450_NVM   0x20
+#define ADXRS450_Q     0x40
+#define ADXRS450_PLL   0x80
+#define ADXRS450_UV    0x100
+#define ADXRS450_OV    0x200
+#define ADXRS450_AMP   0x400
+#define ADXRS450_FAIL  0x800
+
+#define ADXRS450_WRERR_MASK    (0x7 << 29)
+
+#define ADXRS450_MAX_RX 4
+#define ADXRS450_MAX_TX 4
+
+#define ADXRS450_GET_ST(a)     ((a >> 26) & 0x3)
+
+/**
+ * struct adxrs450_state - device instance specific data
+ * @us:                        actual spi_device
+ * @indio_dev:         industrial I/O device structure
+ * @tx:                        transmit buffer
+ * @rx:                        recieve buffer
+ * @buf_lock:          mutex to protect tx and rx
+ **/
+struct adxrs450_state {
+       struct spi_device               *us;
+       struct iio_dev                  *indio_dev;
+       u8                              *tx;
+       u8                              *rx;
+       struct mutex                    buf_lock;
+};
+
+#endif /* SPI_ADXRS450_H_ */
diff --git a/drivers/staging/iio/gyro/adxrs450_core.c b/drivers/staging/iio/gyro/adxrs450_core.c
new file mode 100644 (file)
index 0000000..d70bf68
--- /dev/null
@@ -0,0 +1,446 @@
+/*
+ * 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");