[PATCH 1/2 RESEND v4] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450

[PATCH 1/2 RESEND v4] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450

[cliff.cai]

From: Cliff Cai <cliff.cai@analog.com>

Change v4:v3:
	clean up some nitpicks.

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
---
 drivers/staging/iio/gyro/Kconfig         |   10 +
 drivers/staging/iio/gyro/Makefile        |    3 +
 drivers/staging/iio/gyro/adxrs450.h      |   58 ++++
 drivers/staging/iio/gyro/adxrs450_core.c |  446 ++++++++++++++++++++++++++++++
 4 files changed, 517 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/iio/gyro/adxrs450.h
 create mode 100644 drivers/staging/iio/gyro/adxrs450_core.c

diff --git a/drivers/staging/iio/gyro/Kconfig b/drivers/staging/iio/gyro/Kconfig
index 8b78fa0..ae2e7d3 100644
--- a/drivers/staging/iio/gyro/Kconfig
+++ b/drivers/staging/iio/gyro/Kconfig
@@ -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.
diff --git a/drivers/staging/iio/gyro/Makefile b/drivers/staging/iio/gyro/Makefile
index 2764c15..2212240 100644
--- a/drivers/staging/iio/gyro/Makefile
+++ b/drivers/staging/iio/gyro/Makefile
@@ -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
index 0000000..c92f694
--- /dev/null
+++ b/drivers/staging/iio/gyro/adxrs450.h
@@ -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
index 0000000..2014e5c
--- /dev/null
+++ b/drivers/staging/iio/gyro/adxrs450_core.c
@@ -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@analog.com>");
+MODULE_DESCRIPTION("Analog Devices ADXRS450 Gyroscope SPI driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.1

[PATCH 2/2 RESEND v2] Add ABI document for gyro quadrature correction

[cliff.cai]

From: Cliff Cai <cliff.cai@analog.com>

Change v2:v1:
	Fix typo

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
---
 drivers/staging/iio/Documentation/sysfs-bus-iio |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio b/drivers/staging/iio/Documentation/sysfs-bus-iio
index 4915aee..824a56c 100644
--- a/drivers/staging/iio/Documentation/sysfs-bus-iio
+++ b/drivers/staging/iio/Documentation/sysfs-bus-iio
@@ -698,3 +698,10 @@ Description:
 		with all _en attributes to establish which channels are present,
 		and the relevant _type attributes to establish the data storage
 		format.
+
+What:		/sys/bus/iio/devices/deviceX/gyro_z_quadrature_correction_raw
+KernelVersion:	2.6.38
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This attribute is used to read the amount of quadrature error
+		present in the device at a given time.
-- 
1.7.1

Re: [PATCH 1/2 RESEND v4] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450

[Jonathan Cameron]

On 03/24/11 06:03, cliff.cai@analog.com wrote:
> From: Cliff Cai <cliff.cai@analog.com>
> 
> Change v4:v3:
> 	clean up some nitpicks.
I acked the last version and there have been no major
changes so you should have added that below for this
posting. Same is true of the next patch.

Please add them to your commit messages, respin the
patches series and send on to Greg KH for a merge.
I think you've just missed this merge window so it will
sit in staging-next until the next one opens.

Thanks,
> 
> Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>