[staging] driver for adis16255 gyroscope

matthias mensch0815 at googlemail.com
Wed Apr 28 18:45:35 UTC 2010


This drivers allows a communication with the Analog Devices ADIS16255
Low Power Gyroscope over SPI.

Signed-off-by: Matthias Brugger <mensch0815 at gmail.com>
---
diff --git a/drivers/staging/adis16255/Kconfig
b/drivers/staging/adis16255/Kconfig
new file mode 100644
index 0000000..3952cf9
--- /dev/null
+++ b/drivers/staging/adis16255/Kconfig
@@ -0,0 +1,9 @@
+config ADIS16255
+	tristate "Ananlog Devices ADIS16250/16255"
+	depends on SPI && SYSFS
+	---help---
+      If you say yes here you get support for the Analog Devices
+      ADIS16250/16255 Low Power Gyroscope.
+
+      This driver can also be built as a module. If so, the module
+      will be called adis16255.
diff --git a/drivers/staging/adis16255/Makefile
b/drivers/staging/adis16255/Makefile
new file mode 100644
index 0000000..796dac4
--- /dev/null
+++ b/drivers/staging/adis16255/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_ADIS16255) += adis16255.o
diff --git a/drivers/staging/adis16255/TODO b/drivers/staging/adis16255/TODO
new file mode 100644
index 0000000..255b367
--- /dev/null
+++ b/drivers/staging/adis16255/TODO
@@ -0,0 +1,4 @@
+* documentation about sample rate, possible changes via ioctls etc pp
+* sample rate changeable or at least readable from sysfs
+* reset gyroscope
+* encapsulate adis_init and adis_turn_off
diff --git a/drivers/staging/adis16255/adis16255.c
b/drivers/staging/adis16255/adis16255.c
new file mode 100644
index 0000000..19d7d9c
--- /dev/null
+++ b/drivers/staging/adis16255/adis16255.c
@@ -0,0 +1,388 @@
+/*
+ * Analog Devices ADIS16250/ADIS16255 Low Power Gyroscope
+ *
+ * Written by: Matthias Brugger <mensch0815 at gmail.com>
+ *
+ * Copyright (C) 2010 Fraunhofer Institute for Integrated Circuits
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the
+ * Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+
+#include <linux/interrupt.h>
+#include <linux/sysfs.h>
+#include <linux/stat.h>
+#include <linux/delay.h>
+
+#include <linux/gpio.h>
+
+#include <linux/spi/spi.h>
+#include <linux/workqueue.h>
+
+#include "adis16255.h"
+
+#define ADIS_STATUS        0x3d
+#define ADIS_SMPL_PRD_MSB  0x37
+#define ADIS_SMPL_PRD_LSB  0x36
+#define ADIS_MSC_CTRL_MSB  0x35
+#define ADIS_MSC_CTRL_LSB  0x34
+#define ADIS_GPIO_CTRL     0x33
+#define ADIS_ALM_SMPL1     0x25
+#define ADIS_ALM_MAG1      0x21
+#define ADIS_GYRO_SCALE    0x17
+#define ADIS_GYRO_OUT      0x05
+#define ADIS_SUPPLY_OUT    0x03
+#define ADIS_ENDURANCE     0x01
+
+/*
+ * data structure for every sensor
+ *
+ * @dev:       Driver model representation of the device.
+ * @spi:       Pointer to the spi device which will manage i/o to spi bus.
+ * @wq:        work for working queue
+ * @data:      Last read data from device.
+ * @irq_adis:  GPIO Number of IRQ signal
+ * @irq:       irq line manage by kernel
+ * @negative:  indicates if sensor is upside down (negative == 1)
+ * @direction: indicates x, y, z axis the sensor is meassuring
+ */
+struct spi_adis16255_data {
+   struct device        dev;
+   struct spi_device    *spi;
+   struct work_struct   wq;
+   s16                  data;
+   int                  irq_adis;
+   int                  irq;
+   u8                   negative;
+   char                 direction;
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int spi_adis16255_read_data(struct spi_adis16255_data *spiadis,
+               u8 adr,
+               u8 *rbuf)
+{
+   struct spi_device *spi = spiadis->spi;
+   struct spi_message msg;
+   struct spi_transfer xfer1, xfer2;
+   u8 *buf, *rx;
+   int ret;
+
+   buf = kmalloc(4, GFP_KERNEL);
+   if (!buf)
+      return -ENOMEM;
+
+   rx = kzalloc(4, GFP_KERNEL);
+   if (!rx)
+      return -ENOMEM;
+
+   buf[0] = adr;
+   buf[1] = 0x00;
+   buf[2] = 0x00;
+   buf[3] = 0x00;
+
+   spi_message_init(&msg);
+   memset(&xfer1, 0, sizeof(xfer1));
+   memset(&xfer2, 0, sizeof(xfer2));
+
+   xfer1.tx_buf = buf;
+   xfer1.rx_buf = buf + 2;
+   xfer1.len = 2;
+   xfer1.delay_usecs = 9;
+
+   xfer2.tx_buf = rx + 2;
+   xfer2.rx_buf = rx;
+   xfer2.len = 2;
+
+   spi_message_add_tail(&xfer1, &msg);
+   spi_message_add_tail(&xfer2, &msg);
+
+   ret = spi_sync(spi, &msg);
+   if (ret == 0) {
+      rbuf[0] = rx[0];
+      rbuf[1] = rx[1];
+   }
+
+   kfree(buf);
+   kfree(rx);
+
+   return ret;
+}
+
+static int spi_adis16255_write_data(struct spi_adis16255_data *spiadis,
+               u8 adr1,
+               u8 adr2,
+               u8* wbuf)
+{
+   struct spi_device *spi = spiadis->spi;
+   struct spi_message   msg;
+   struct spi_transfer  xfer1, xfer2;
+   u8       *buf, *rx;
+   int         ret;
+
+   buf = kmalloc(4, GFP_KERNEL);
+   if (!buf)
+      return -ENOMEM;
+
+   rx = kzalloc(4, GFP_KERNEL);
+   if (!rx)
+      return -ENOMEM;
+
+   spi_message_init(&msg);
+   memset(&xfer1, 0, sizeof(xfer1));
+   memset(&xfer2, 0, sizeof(xfer2));
+
+   buf[0] = adr1 | 0x80;
+   buf[1] = *wbuf;
+
+   buf[2] = adr2 | 0x80;
+   buf[3] = *(wbuf + 1);
+
+   xfer1.tx_buf = buf;
+   xfer1.rx_buf = rx;
+   xfer1.len = 2;
+   xfer1.delay_usecs = 9;
+
+   xfer2.tx_buf = buf+2;
+   xfer2.rx_buf = rx+2;
+   xfer2.len = 2;
+
+   spi_message_add_tail(&xfer1, &msg);
+   spi_message_add_tail(&xfer2, &msg);
+
+   ret = spi_sync(spi, &msg);
+   if (ret != 0)
+      dev_info(&spi->dev, "wirte data to %#x %#x failed\n", buf[0], buf[2]);
+
+   kfree(buf);
+   kfree(rx);
+   return ret;
+}
+
+/*-------------------------------------------------------------------------*/
+
+void spi_workqueue(struct work_struct *work)
+{
+   struct spi_adis16255_data *spiadis = container_of(work, struct
spi_adis16255_data, wq);
+   int status;
+   u16 value;
+
+   status =  spi_adis16255_read_data(spiadis, ADIS_GYRO_OUT, (u8 *)&value);
+   if (status == 0) {
+      // perform on new data only...
+      // delete error and new data bit
+      // set negative value
+      if (value & 0x8000) {
+         value = value & 0x3fff;
+         if (value & 0x2000) {
+            value = value | 0xe000;
+
+         if(likely(spiadis->negative))
+            value = -value;
+
+         spiadis->data = (s16) value;
+      }
+   }
+   else {
+      dev_warn(&spiadis->spi->dev, "SPI FAILED");
+   }
+
+}
+
+static irqreturn_t adis_interrupt(int irq, void *dev_id) {
+   struct spi_adis16255_data *spiadis = (struct spi_adis16255_data *) dev_id;
+
+   schedule_work(&spiadis->wq);
+
+   return IRQ_HANDLED;
+}
+
+/*-------------------------------------------------------------------------*/
+
+ssize_t adis16255_show_data(struct device *device, struct
device_attribute* da, char *buf)
+{
+   struct spi_adis16255_data *spiadis = dev_get_drvdata(device);
+   return snprintf(buf, PAGE_SIZE, "%d\n", spiadis->data);
+}
+DEVICE_ATTR(data, S_IRUGO , adis16255_show_data, NULL);
+
+ssize_t adis16255_show_direction(struct device *device, struct
device_attribute* da, char *buf)
+{
+   struct spi_adis16255_data *spiadis = dev_get_drvdata(device);
+   return snprintf(buf, PAGE_SIZE, "%c\n", spiadis->direction);
+}
+DEVICE_ATTR(direction, S_IRUGO , adis16255_show_direction, NULL);
+
+static struct attribute *adis16255_attributes[] = {
+   &dev_attr_data.attr,
+   &dev_attr_direction.attr,
+   NULL
+};
+
+static const struct attribute_group adis16255_attr_group = {
+   .attrs = adis16255_attributes,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int spi_adis16255_probe(struct spi_device *spi)
+{
+
+#define AD_CHK(_ss)  \
+{                    \
+   status = _ss;     \
+   if(status != 0)   \
+      goto irq_err;  \
+}
+
+   struct adis16255_init_data *init_data = spi->dev.platform_data;
+   struct spi_adis16255_data  *spiadis;
+   int status=0;
+   u16 value;
+
+   /* Allocate driver data */
+   spiadis = kzalloc(sizeof(*spiadis), GFP_KERNEL);
+   if (!spiadis)
+      return -ENOMEM;
+
+   spiadis->spi = spi; // save spi_device in driver-data
+   spiadis->irq_adis = init_data->irq;
+   spiadis->direction = init_data->direction;
+
+   if (init_data->negative) {
+      spiadis->negative = 1;
+   }
+
+   INIT_WORK(&spiadis->wq, spi_workqueue);
+
+
+   status = gpio_request(spiadis->irq_adis, "adis16255");
+   if(status != 0)
+      goto irq_err;
+
+   status = gpio_direction_input(spiadis->irq_adis);
+   if(status != 0)
+      goto irq_err;
+
+   spiadis->irq = gpio_to_irq(spiadis->irq_adis);
+
+   status = request_irq(spiadis->irq, adis_interrupt, IRQF_DISABLED,
"adis-driver", spiadis);
+   if(status != 0) {
+      dev_err(&spi->dev, "IRQ request failed\n");
+      goto irq_err;
+   }
+
+   dev_dbg(&spi->dev, "GPIO %d IRQ %d\n", spiadis->irq_adis, spiadis->irq);
+
+   dev_set_drvdata(&spi->dev, spiadis);
+   AD_CHK(sysfs_create_group(&spi->dev.kobj, &adis16255_attr_group));
+
+   dev_info(&spi->dev,"spi_adis16255 driver added!\n");
+
+   AD_CHK( spi_adis16255_read_data(spiadis, ADIS_SUPPLY_OUT, (u8 *)&value) );
+   dev_info(&spi->dev, "sensor works with %d mV (%.4x)!\n", ((value &
0x0fff)*18315)/10000, (value & 0x0fff));
+
+   AD_CHK( spi_adis16255_read_data(spiadis, ADIS_GYRO_SCALE, (u8 *)&value) );
+   dev_info(&spi->dev, "adis GYRO_SCALE is %.4x\n", value);
+
+   AD_CHK( spi_adis16255_read_data(spiadis, ADIS_STATUS, (u8 *)&value) );
+   dev_info(&spi->dev, "adis STATUS is %.4x\n", value);
+
+   value =  0x0001;// 0x008a;
+   AD_CHK( spi_adis16255_write_data(spiadis, ADIS_SMPL_PRD_MSB,
ADIS_SMPL_PRD_LSB, (u8 *)&value) );
+   value = 0x0000;
+   AD_CHK( spi_adis16255_read_data(spiadis, ADIS_SMPL_PRD_MSB, (u8 *)&value) );
+   dev_info(&spi->dev, "adis SMP_PRD is %.4x\n", value);
+
+   // set interrupt on new data...
+   value = 0x0006;
+   AD_CHK( spi_adis16255_write_data(spiadis, ADIS_MSC_CTRL_MSB,
ADIS_MSC_CTRL_LSB, (u8 *)&value) );
+   value = 0x0000;
+   AD_CHK( spi_adis16255_read_data(spiadis, ADIS_MSC_CTRL_MSB, (u8 *)&value) );
+   dev_info(&spi->dev, "adis MSC_CONTROL is %.4x\n", value);
+
+   return status;
+
+irq_err:
+   kfree(spiadis);
+   return status;
+}
+
+static int spi_adis16255_remove(struct spi_device *spi)
+{
+   u16 value=0;
+   struct spi_adis16255_data  *spiadis    = dev_get_drvdata(&spi->dev);
+   struct adis16255_init_data *init_data  = spi->dev.platform_data;
+
+   if(spiadis == NULL) {
+      dev_info(&spi->dev, "unregister: no spiadis struct %c\n",
init_data->direction);
+      goto end;
+   }
+
+   // trun sensor off
+   spi_adis16255_write_data(spiadis, ADIS_SMPL_PRD_MSB,
ADIS_SMPL_PRD_LSB, (u8 *)&value);
+   spi_adis16255_write_data(spiadis, ADIS_MSC_CTRL_MSB,
ADIS_MSC_CTRL_LSB, (u8 *)&value);
+
+   dev_info(&spi->dev, "unregister: GPIO %d IRQ %d
\n",spiadis->irq_adis, spiadis->irq);
+   free_irq(spiadis->irq, spiadis);
+   gpio_free(spiadis->irq_adis);
+
+   sysfs_remove_group(&spiadis->spi->dev.kobj, &adis16255_attr_group);
+
+   kfree(spiadis);
+
+end:
+   dev_info(&spi->dev, "spi_adis16255 driver removed!\n");
+   return 0;
+}
+
+static struct spi_driver spi_adis16255_drv = {
+   .driver = {
+      .name =  "spi_adis16255",
+      .owner = THIS_MODULE,
+   },
+   .probe = spi_adis16255_probe,
+   .remove =   __devexit_p(spi_adis16255_remove),
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int __init spi_adis16255_init(void)
+{
+   int status;
+
+   status = spi_register_driver(&spi_adis16255_drv);
+   return status;
+}
+module_init(spi_adis16255_init);
+
+static void __exit spi_adis16255_exit(void)
+{
+   spi_unregister_driver(&spi_adis16255_drv);
+}
+module_exit(spi_adis16255_exit);
+
+MODULE_AUTHOR("Matthias Brugger");
+MODULE_DESCRIPTION("SPI device driver for ADIS16255 sensor");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/adis16255/adis16255.h
b/drivers/staging/adis16255/adis16255.h
new file mode 100644
index 0000000..26c9f84
--- /dev/null
+++ b/drivers/staging/adis16255/adis16255.h
@@ -0,0 +1,12 @@
+#ifndef ADIS16255_H
+#define ADIS16255_H
+
+#include <linux/types.h>
+
+struct adis16255_init_data {
+   char direction;
+   u8   negative;
+   int  irq;
+};
+
+#endif



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