* [PATCH] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450
@ 2011-02-14 9:47 test
2011-02-14 11:40 ` [Device-drivers-devel] " Michael Hennerich
0 siblings, 1 reply; 3+ messages in thread
From: test @ 2011-02-14 9:47 UTC (permalink / raw)
To: linux-iio, linux-kernel; +Cc: drivers, jic23, device-drivers-devel, Cliff Cai
From: Cliff Cai <cliff.cai@analog.com>
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 | 48 +++
drivers/staging/iio/gyro/adxrs450_core.c | 471 ++++++++++++++++++++++++++++++
4 files changed, 532 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 236f15f..3432967 100644
--- a/drivers/staging/iio/gyro/Kconfig
+++ b/drivers/staging/iio/gyro/Kconfig
@@ -45,3 +45,13 @@ config ADIS16251
This driver can also be built as a module. If so, the module
will be called adis16251.
+
+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..5d8566a
--- /dev/null
+++ b/drivers/staging/iio/gyro/adxrs450.h
@@ -0,0 +1,48 @@
+#ifndef SPI_ADXRS450_H_
+#define SPI_ADXRS450_H_
+
+#define ADXRS450_STARTUP_DELAY 50 /* ms */
+
+/* The MSB for the spi commands */
+#define ADXRS450_SENSOR_DATA (0x2 << 27 | 0x1)
+#define ADXRS450_READ_REG(a) ((0x20 << 26) | (a << 17) | 0x1)
+#define ADXRS450_WRITE_REG(a, value) \
+ ((0x10 << 26) | (a << 17) | (value << 1) | 0x1)
+
+#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 Registers */
+#define ADXRS450_SNH 0x0E /* Serial Number Registers, 4 bytes */
+#define ADXRS450_SNL 0x10
+#define ADXRS450_DNC1 0x12 /* Dynamic Null Correction Registers */
+
+#define ADXRS450_WRERR_MASK (0x7 << 29)
+
+#define ADXRS450_MAX_RX 1
+#define ADXRS450_MAX_TX 1
+
+#define ADXRS450_SPI_SLOW (u32)(300 * 1000)
+#define ADXRS450_SPI_FAST (u32)(2000 * 1000)
+#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;
+ u32 *tx;
+ u32 *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..4feb653
--- /dev/null
+++ b/drivers/staging/iio/gyro/adxrs450_core.c
@@ -0,0 +1,471 @@
+/*
+ * ADXRS450 Digital Output Gyroscope Driver
+ *
+ * Copyright 2010 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"
+
+#define DRIVER_NAME "adxrs450"
+
+/* ADXRS450 only support 32-bit spi transfer, all the registers are read only */
+
+
+/**
+ * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
+ * @dev: device associated with child of actual device (iio_dev or iio_trig)
+ * @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,
+ .bits_per_word = 32,
+ .len = 4,
+ .cs_change = 1,
+ }, {
+ .rx_buf = st->rx,
+ .bits_per_word = 32,
+ .len = 4,
+ .cs_change = 1,
+ },
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_READ_REG(reg_address);
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers[0], &msg);
+ spi_message_add_tail(&xfers[1], &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[0] >> 5);
+
+error_ret:
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+/**
+ * adxrs450_spi_sensor_data() - read 2 bytes sensor data
+ * @dev: device associated with child of actual device (iio_dev or iio_trig)
+ * @val: somewhere to pass back the value read
+ **/
+static int adxrs450_spi_sensor_data(struct device *dev,
+ u32 *val, char chk)
+{
+ 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,
+ .bits_per_word = 32,
+ .len = 4,
+ .cs_change = 1,
+ }, {
+ .rx_buf = st->rx,
+ .bits_per_word = 32,
+ .len = 4,
+ .cs_change = 1,
+ },
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADXRS450_SENSOR_DATA;
+ if (chk)
+ st->tx[0] |= 0x2;
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers[0], &msg);
+ spi_message_add_tail(&xfers[1], &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];
+
+error_ret:
+ mutex_unlock(&st->buf_lock);
+ return ret;
+}
+
+static ssize_t adxrs450_read_rate(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_RATE1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_temp(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_TEMP1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_locst(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_LOCST1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_hicst(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_HICST1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_quad(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_QUAD1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_fault(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_FAULT1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_pid(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_PID1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_sn(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t0, t1;
+ u32 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_SNH,
+ &t0);
+ if (ret)
+ return ret;
+
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_SNL,
+ &t1);
+ if (ret)
+ return ret;
+ t = (t0 << 16) | t1;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_dnc(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u16 t;
+ ret = adxrs450_spi_read_reg_16(dev,
+ ADXRS450_DNC1,
+ &t);
+ if (ret)
+ return ret;
+ len = sprintf(buf, "%d\n", t);
+ return len;
+}
+
+static ssize_t adxrs450_read_sensor_data(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int ret, len = 0;
+ u32 t;
+ u16 data;
+ ret = adxrs450_spi_sensor_data(dev, &t, 0);
+ if (ret)
+ return ret;
+ data = (u16)(t >> 10);
+ len = sprintf(buf, "%d\n", data);
+ return len;
+}
+
+/* Recommeded Startup Sequence by spec */
+static int adxrs450_initial_setup(struct adxrs450_state *st)
+{
+ u32 t;
+ int ret;
+ struct device *dev = &st->indio_dev->dev;
+ /* use low spi speed for init */
+ st->us->max_speed_hz = ADXRS450_SPI_SLOW;
+ st->us->chip_select = 4;
+ st->us->mode = SPI_MODE_0;
+ spi_setup(st->us);
+
+ msleep(ADXRS450_STARTUP_DELAY*2);
+
+ ret = adxrs450_spi_sensor_data(dev, &t, 1);
+ if (ret)
+ return ret;
+ if (t != 0x00000001)
+ return -ENODEV;
+
+ msleep(ADXRS450_STARTUP_DELAY);
+ ret = adxrs450_spi_sensor_data(dev, &t, 0);
+ if (ret)
+ return ret;
+ msleep(ADXRS450_STARTUP_DELAY);
+ ret = adxrs450_spi_sensor_data(dev, &t, 0);
+ if (ret)
+ return ret;
+ if (((t & 0xff) != 0xff) && (ADXRS450_GET_ST(t) != 2))
+ return -EIO;
+ ret = adxrs450_spi_sensor_data(dev, &t, 0);
+ if (ret)
+ return ret;
+ if (((t & 0xff) != 0xff) && (ADXRS450_GET_ST(t) != 2))
+ return -EIO;
+
+ printk(KERN_INFO DRIVER_NAME ": at CS%d\n",
+ st->us->chip_select);
+
+ return 0;
+}
+
+static IIO_DEVICE_ATTR(sensor_data, S_IRUGO,
+ adxrs450_read_sensor_data, NULL, 0);
+static IIO_DEVICE_ATTR(rate, S_IRUGO,
+ adxrs450_read_rate, NULL, 0);
+static IIO_DEVICE_ATTR(temperature, S_IRUGO,
+ adxrs450_read_temp, NULL, 0);
+static IIO_DEVICE_ATTR(low_cst, S_IRUGO,
+ adxrs450_read_locst, NULL, 0);
+static IIO_DEVICE_ATTR(high_cst, S_IRUGO,
+ adxrs450_read_hicst, NULL, 0);
+static IIO_DEVICE_ATTR(quad, S_IRUGO,
+ adxrs450_read_quad, NULL, 0);
+static IIO_DEVICE_ATTR(fault, S_IRUGO,
+ adxrs450_read_fault, NULL, 0);
+static IIO_DEVICE_ATTR(part_id, S_IRUGO,
+ adxrs450_read_pid, NULL, 0);
+static IIO_DEVICE_ATTR(serial_number, S_IRUGO,
+ adxrs450_read_sn, NULL, 0);
+static IIO_DEVICE_ATTR(dynamic_null_correction, S_IRUGO,
+ adxrs450_read_dnc, NULL, 0);
+
+
+static IIO_CONST_ATTR(name, "adxrs450");
+
+static struct attribute *adxrs450_attributes[] = {
+
+ &iio_dev_attr_sensor_data.dev_attr.attr,
+ &iio_dev_attr_rate.dev_attr.attr,
+ &iio_dev_attr_temperature.dev_attr.attr,
+ &iio_dev_attr_low_cst.dev_attr.attr,
+ &iio_dev_attr_high_cst.dev_attr.attr,
+ &iio_dev_attr_quad.dev_attr.attr,
+ &iio_dev_attr_fault.dev_attr.attr,
+ &iio_dev_attr_part_id.dev_attr.attr,
+ &iio_dev_attr_serial_number.dev_attr.attr,
+ &iio_dev_attr_dynamic_null_correction.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;
+}
+
+/* fixme, confirm ordering in this function */
+static int adxrs450_remove(struct spi_device *spi)
+{
+ struct adxrs450_state *st = spi_get_drvdata(spi);
+ struct iio_dev *indio_dev = st->indio_dev;
+
+ iio_device_unregister(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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [Device-drivers-devel] [PATCH] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450
2011-02-14 9:47 [PATCH] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450 test
@ 2011-02-14 11:40 ` Michael Hennerich
2011-02-22 14:01 ` Jonathan Cameron
0 siblings, 1 reply; 3+ messages in thread
From: Michael Hennerich @ 2011-02-14 11:40 UTC (permalink / raw)
To: test
Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Drivers,
Cai, Cliff, jic23@cam.ac.uk,
device-drivers-devel@blackfin.uclinux.org
Hi Cliff,
Exposing every single register to user space is not an acceptable driver.
Ideally a user of this driver doesn't need to read the datasheet, only
the IIO ABI Documentation.
This driver can also benefit from triggered sampling/ring buffer support.
please see comments below.
On 02/14/2011 10:47 AM, test wrote:
> From: Cliff Cai <cliff.cai@analog.com>
>
> 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 | 48 +++
> drivers/staging/iio/gyro/adxrs450_core.c | 471 ++++++++++++++++++++++++++++++
> 4 files changed, 532 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 236f15f..3432967 100644
> --- a/drivers/staging/iio/gyro/Kconfig
> +++ b/drivers/staging/iio/gyro/Kconfig
> @@ -45,3 +45,13 @@ config ADIS16251
>
> This driver can also be built as a module. If so, the module
> will be called adis16251.
> +
> +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..5d8566a
> --- /dev/null
> +++ b/drivers/staging/iio/gyro/adxrs450.h
> @@ -0,0 +1,48 @@
> +#ifndef SPI_ADXRS450_H_
> +#define SPI_ADXRS450_H_
> +
> +#define ADXRS450_STARTUP_DELAY 50 /* ms */
> +
> +/* The MSB for the spi commands */
> +#define ADXRS450_SENSOR_DATA (0x2 << 27 | 0x1)
> +#define ADXRS450_READ_REG(a) ((0x20 << 26) | (a << 17) | 0x1)
> +#define ADXRS450_WRITE_REG(a, value) \
> + ((0x10 << 26) | (a << 17) | (value << 1) | 0x1)
> +
> +#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 Registers */
> +#define ADXRS450_SNH 0x0E /* Serial Number Registers, 4 bytes */
> +#define ADXRS450_SNL 0x10
> +#define ADXRS450_DNC1 0x12 /* Dynamic Null Correction Registers */
> +
> +#define ADXRS450_WRERR_MASK (0x7 << 29)
> +
> +#define ADXRS450_MAX_RX 1
> +#define ADXRS450_MAX_TX 1
> +
> +#define ADXRS450_SPI_SLOW (u32)(300 * 1000)
> +#define ADXRS450_SPI_FAST (u32)(2000 * 1000)
> +#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;
> + u32 *tx;
> + u32 *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..4feb653
> --- /dev/null
> +++ b/drivers/staging/iio/gyro/adxrs450_core.c
> @@ -0,0 +1,471 @@
> +/*
> + * ADXRS450 Digital Output Gyroscope Driver
> + *
> + * Copyright 2010 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"
> +
> +#define DRIVER_NAME "adxrs450"
> +
> +/* ADXRS450 only support 32-bit spi transfer, all the registers are read only */
> +
> +
> +/**
> + * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
> + * @dev: device associated with child of actual device (iio_dev or iio_trig)
> + * @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,
> + .bits_per_word = 32,
> + .len = 4,
> + .cs_change = 1,
> + }, {
> + .rx_buf = st->rx,
> + .bits_per_word = 32,
> + .len = 4,
> + .cs_change = 1,
>
I don't think you want cs_change = 1 in the last transfer of an message!
It'll cause bad behavior, since cs_will be asserted after the message
finishes.
> + },
> + };
> +
> + mutex_lock(&st->buf_lock);
> + st->tx[0] = ADXRS450_READ_REG(reg_address);
>
Endianess?
Please make sure that this driver works on both LE/BE
> + spi_message_init(&msg);
> + spi_message_add_tail(&xfers[0], &msg);
> + spi_message_add_tail(&xfers[1], &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[0] >> 5);
> +
> +error_ret:
> + mutex_unlock(&st->buf_lock);
> + return ret;
> +}
> +
> +/**
> + * adxrs450_spi_sensor_data() - read 2 bytes sensor data
> + * @dev: device associated with child of actual device (iio_dev or iio_trig)
> + * @val: somewhere to pass back the value read
> + **/
> +static int adxrs450_spi_sensor_data(struct device *dev,
> + u32 *val, char chk)
> +{
> + 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,
> + .bits_per_word = 32,
> + .len = 4,
> + .cs_change = 1,
> + }, {
> + .rx_buf = st->rx,
> + .bits_per_word = 32,
> + .len = 4,
> + .cs_change = 1,
> + },
> + };
> +
> + mutex_lock(&st->buf_lock);
> + st->tx[0] = ADXRS450_SENSOR_DATA;
> + if (chk)
> + st->tx[0] |= 0x2;
> + spi_message_init(&msg);
> + spi_message_add_tail(&xfers[0], &msg);
> + spi_message_add_tail(&xfers[1], &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];
> +
> +error_ret:
> + mutex_unlock(&st->buf_lock);
> + return ret;
> +}
> +
> +static ssize_t adxrs450_read_rate(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_RATE1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_temp(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_TEMP1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_locst(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_LOCST1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_hicst(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_HICST1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_quad(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_QUAD1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_fault(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_FAULT1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_pid(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_PID1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_sn(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t0, t1;
> + u32 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_SNH,
> + &t0);
> + if (ret)
> + return ret;
> +
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_SNL,
> + &t1);
> + if (ret)
> + return ret;
> + t = (t0 << 16) | t1;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_dnc(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u16 t;
> + ret = adxrs450_spi_read_reg_16(dev,
> + ADXRS450_DNC1,
> + &t);
> + if (ret)
> + return ret;
> + len = sprintf(buf, "%d\n", t);
> + return len;
> +}
> +
> +static ssize_t adxrs450_read_sensor_data(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int ret, len = 0;
> + u32 t;
> + u16 data;
> + ret = adxrs450_spi_sensor_data(dev, &t, 0);
> + if (ret)
> + return ret;
> + data = (u16)(t >> 10);
> + len = sprintf(buf, "%d\n", data);
> + return len;
> +}
> +
> +/* Recommeded Startup Sequence by spec */
> +static int adxrs450_initial_setup(struct adxrs450_state *st)
> +{
> + u32 t;
> + int ret;
> + struct device *dev = &st->indio_dev->dev;
> + /* use low spi speed for init */
> + st->us->max_speed_hz = ADXRS450_SPI_SLOW;
> + st->us->chip_select = 4;
>
Don't hardcode the chip_select
> + st->us->mode = SPI_MODE_0;
>
Does the part work in other SPI modes as well?
If so, don't hard code.
> + spi_setup(st->us);
>
Check return value.
> +
> + msleep(ADXRS450_STARTUP_DELAY*2);
> +
> + ret = adxrs450_spi_sensor_data(dev, &t, 1);
> + if (ret)
> + return ret;
> + if (t != 0x00000001)
> + return -ENODEV;
> +
> + msleep(ADXRS450_STARTUP_DELAY);
> + ret = adxrs450_spi_sensor_data(dev, &t, 0);
> + if (ret)
> + return ret;
> + msleep(ADXRS450_STARTUP_DELAY);
> + ret = adxrs450_spi_sensor_data(dev, &t, 0);
> + if (ret)
> + return ret;
> + if (((t & 0xff) != 0xff) && (ADXRS450_GET_ST(t) != 2))
> + return -EIO;
> + ret = adxrs450_spi_sensor_data(dev, &t, 0);
> + if (ret)
> + return ret;
> + if (((t & 0xff) != 0xff) && (ADXRS450_GET_ST(t) != 2))
> + return -EIO;
> +
> + printk(KERN_INFO DRIVER_NAME ": at CS%d\n",
> + st->us->chip_select);
>
Don't use printk!
use dev_dbg, dev_info, dev_warn, dev_err, etc.
> +
> + return 0;
> +}
> +
>
Please read iio/Documentation and conform with the ABI.
> +static IIO_DEVICE_ATTR(sensor_data, S_IRUGO,
> + adxrs450_read_sensor_data, NULL, 0);
> +static IIO_DEVICE_ATTR(rate, S_IRUGO,
> + adxrs450_read_rate, NULL, 0);
>
Use gyro_z_raw. I don't think we need both here.
> +static IIO_DEVICE_ATTR(temperature, S_IRUGO,
> + adxrs450_read_temp, NULL, 0);
>
Use temp or temp_raw.
> +static IIO_DEVICE_ATTR(low_cst, S_IRUGO,
> + adxrs450_read_locst, NULL, 0);
> +static IIO_DEVICE_ATTR(high_cst, S_IRUGO,
> + adxrs450_read_hicst, NULL, 0);
>
I don't think we need the self-test registers exposed this way.
We could create a new file self_test, and implement the complete self
test sequence.
Then just return success.
> +static IIO_DEVICE_ATTR(quad, S_IRUGO,
> + adxrs450_read_quad, NULL, 0);
> +static IIO_DEVICE_ATTR(fault, S_IRUGO,
> + adxrs450_read_fault, NULL, 0);
>
Don't expose the fault register.
The FAULT0 register is appended to the end of every device data
transmission.
Check for error status and return -EFAULT, in case of an error.
During probe check for POR, PLL, etc. errors and abort in case of errors.
> +static IIO_DEVICE_ATTR(part_id, S_IRUGO,
> + adxrs450_read_pid, NULL, 0);
> +static IIO_DEVICE_ATTR(serial_number, S_IRUGO,
> + adxrs450_read_sn, NULL, 0);
>
Don't expose part and serial number.
You could read them during probe and add to the dev_info string.
> +static IIO_DEVICE_ATTR(dynamic_null_correction, S_IRUGO,
> + adxrs450_read_dnc, NULL, 0);
>
Please add documentation for this file.
> +
> +
> +static IIO_CONST_ATTR(name, "adxrs450");
> +
> +static struct attribute *adxrs450_attributes[] = {
> +
> + &iio_dev_attr_sensor_data.dev_attr.attr,
> + &iio_dev_attr_rate.dev_attr.attr,
> + &iio_dev_attr_temperature.dev_attr.attr,
> + &iio_dev_attr_low_cst.dev_attr.attr,
> + &iio_dev_attr_high_cst.dev_attr.attr,
> + &iio_dev_attr_quad.dev_attr.attr,
> + &iio_dev_attr_fault.dev_attr.attr,
> + &iio_dev_attr_part_id.dev_attr.attr,
> + &iio_dev_attr_serial_number.dev_attr.attr,
> + &iio_dev_attr_dynamic_null_correction.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;
> +}
> +
> +/* fixme, confirm ordering in this function */
> +static int adxrs450_remove(struct spi_device *spi)
> +{
> + struct adxrs450_state *st = spi_get_drvdata(spi);
> + struct iio_dev *indio_dev = st->indio_dev;
> +
> + iio_device_unregister(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
>
> _______________________________________________
> Device-drivers-devel mailing list
> Device-drivers-devel@blackfin.uclinux.org
> https://blackfin.uclinux.org/mailman/listinfo/device-drivers-devel
>
--
Greetings,
Michael
--
Analog Devices GmbH Wilhelm-Wagenfeld-Str. 6 80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [Device-drivers-devel] [PATCH] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450
2011-02-14 11:40 ` [Device-drivers-devel] " Michael Hennerich
@ 2011-02-22 14:01 ` Jonathan Cameron
0 siblings, 0 replies; 3+ messages in thread
From: Jonathan Cameron @ 2011-02-22 14:01 UTC (permalink / raw)
To: Cai, Cliff
Cc: Michael Hennerich, linux-iio@vger.kernel.org,
linux-kernel@vger.kernel.org, Drivers,
device-drivers-devel@blackfin.uclinux.org
On 02/14/11 11:40, Michael Hennerich wrote:
> Hi Cliff,
>
> Exposing every single register to user space is not an acceptable driver.
> Ideally a user of this driver doesn't need to read the datasheet, only
> the IIO ABI Documentation.
> This driver can also benefit from triggered sampling/ring buffer support.
At some point.... I wouldn't necessarily advocate this for an initial merge. doing
it in two steps can make for bite sized reviews which definitely have their
advantages!
Given Michael has done a thorough review (thanks) I'll leave looking at this until
you've addressed his comments. Please be careful to avoid dead email addresses (test@analog.com)
Thanks,
Jonathan
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2011-02-22 14:00 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2011-02-14 9:47 [PATCH] IIO driver for Analog Devices Digital Output Gyroscope ADXRS450 test
2011-02-14 11:40 ` [Device-drivers-devel] " Michael Hennerich
2011-02-22 14:01 ` Jonathan Cameron
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