--- /dev/null
+/*
+ * Analog Devices ADIS16250/ADIS16255 Low Power Gyroscope
+ *
+ * Written by: Matthias Brugger <m_brugger@web.de>
+ *
+ * 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.
+ * @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 axis (x, y, z) the sensor is meassuring
+ */
+struct spi_adis16255_data {
+ struct device dev;
+ struct spi_device *spi;
+ 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 �piadis->spi;
+ struct spi_message msg;
+ struct spi_transfer xfer1, xfer2;
+ u8 *buf, *rx;
+ int ret;
+
+ buf �malloc(4, GFP_KERNEL);
+ if (buf �NULL)
+ return -ENOMEM;
+
+ rx �zalloc(4, GFP_KERNEL);
+ if (rx �NULL) {
+ ret �ENOMEM;
+ goto err_buf;
+ }
+
+ buf[0] �dr;
+ buf[1] 羵00;
+ buf[2] 羵00;
+ buf[3] 羵00;
+
+ spi_message_init(&msg);
+ memset(&xfer1, 0, sizeof(xfer1));
+ memset(&xfer2, 0, sizeof(xfer2));
+
+ xfer1.tx_buf �uf;
+ xfer1.rx_buf �uf + 2;
+ xfer1.len �;
+ xfer1.delay_usecs �;
+
+ xfer2.tx_buf �x + 2;
+ xfer2.rx_buf �x;
+ xfer2.len �;
+
+ spi_message_add_tail(&xfer1, &msg);
+ spi_message_add_tail(&xfer2, &msg);
+
+ ret �pi_sync(spi, &msg);
+ if (ret �0) {
+ rbuf[0] �x[0];
+ rbuf[1] �x[1];
+ }
+
+ kfree(rx);
+err_buf:
+ kfree(buf);
+
+ return ret;
+}
+
+static int spi_adis16255_write_data(struct spi_adis16255_data *spiadis,
+ u8 adr1,
+ u8 adr2,
+ u8 *wbuf)
+{
+ struct spi_device *spi �piadis->spi;
+ struct spi_message msg;
+ struct spi_transfer xfer1, xfer2;
+ u8 *buf, *rx;
+ int ret;
+
+ buf �malloc(4, GFP_KERNEL);
+ if (buf �NULL)
+ return -ENOMEM;
+
+ rx �zalloc(4, GFP_KERNEL);
+ if (rx �NULL) {
+ ret �ENOMEM;
+ goto err_buf;
+ }
+
+ spi_message_init(&msg);
+ memset(&xfer1, 0, sizeof(xfer1));
+ memset(&xfer2, 0, sizeof(xfer2));
+
+ buf[0] �dr1 | 0x80;
+ buf[1] �wbuf;
+
+ buf[2] �dr2 | 0x80;
+ buf[3] �(wbuf + 1);
+
+ xfer1.tx_buf �uf;
+ xfer1.rx_buf �x;
+ xfer1.len �;
+ xfer1.delay_usecs �;
+
+ xfer2.tx_buf �uf+2;
+ xfer2.rx_buf �x+2;
+ xfer2.len �;
+
+ spi_message_add_tail(&xfer1, &msg);
+ spi_message_add_tail(&xfer2, &msg);
+
+ ret �pi_sync(spi, &msg);
+ if (ret !�)
+ dev_warn(&spi->dev, "wirte data to %#x %#x failed\n",
+ buf[0], buf[2]);
+
+ kfree(rx);
+err_buf:
+ kfree(buf);
+ return ret;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static irqreturn_t adis_irq_thread(int irq, void *dev_id)
+{
+ struct spi_adis16255_data *spiadis �ev_id;
+ int status;
+ u16 value;
+
+ status �spi_adis16255_read_data(spiadis, ADIS_GYRO_OUT, (u8 *)&value);
+ if (status �0) {
+ /* perform on new data only... */
+ if (value & 0x8000) {
+ /* delete error and new data bit */
+ value �alue & 0x3fff;
+ /* set negative value */
+ if (value & 0x2000)
+ value �alue | 0xe000;
+
+ if (likely(spiadis->negative))
+ value �value;
+
+ spiadis->data �s16) value;
+ }
+ } else {
+ dev_warn(&spiadis->spi->dev, "SPI FAILED\n");
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*-------------------------------------------------------------------------*/
+
+ssize_t adis16255_show_data(struct device *device,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct spi_adis16255_data *spiadis �ev_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 �ev_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 �dis16255_attributes,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int spi_adis16255_probe(struct spi_device *spi)
+{
+
+#define AD_CHK(_ss)\
+ do {\
+ status �ss;\
+ if (status !�)\
+ goto irq_err;\
+ } while (0);
+
+ struct adis16255_init_data *init_data �pi->dev.platform_data;
+ struct spi_adis16255_data *spiadis;
+ int status �;
+ u16 value;
+
+ spiadis �zalloc(sizeof(*spiadis), GFP_KERNEL);
+ if (!spiadis)
+ return -ENOMEM;
+
+ spiadis->spi �pi;
+ spiadis->irq_adis �nit_data->irq;
+ spiadis->direction �nit_data->direction;
+
+ if (init_data->negative)
+ spiadis->negative �;
+
+ status �pio_request(spiadis->irq_adis, "adis16255");
+ if (status !�)
+ goto err;
+
+ status �pio_direction_input(spiadis->irq_adis);
+ if (status !�)
+ goto gpio_err;
+
+ spiadis->irq �pio_to_irq(spiadis->irq_adis);
+
+ status �equest_threaded_irq(spiadis->irq,
+ NULL, adis_irq_thread,
+ IRQF_DISABLED, "adis-driver", spiadis);
+
+ if (status !�) {
+ dev_err(&spi->dev, "IRQ request failed\n");
+ goto gpio_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);
+
+ /* timebase �.953 ms, Ns � -> 512 Hz sample rate */
+ value �0x0001;
+ AD_CHK(spi_adis16255_write_data(spiadis,
+ ADIS_SMPL_PRD_MSB, ADIS_SMPL_PRD_LSB,
+ (u8 *)&value));
+ value 羵0000;
+ 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 羵0006;
+ AD_CHK(spi_adis16255_write_data(spiadis,
+ ADIS_MSC_CTRL_MSB, ADIS_MSC_CTRL_LSB,
+ (u8 *)&value));
+ value 羵0000;
+ 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:
+ free_irq(spiadis->irq, spiadis);
+gpio_err:
+ gpio_free(spiadis->irq_adis);
+err:
+ kfree(spiadis);
+ return status;
+}
+
+static int spi_adis16255_remove(struct spi_device *spi)
+{
+ u16 value �;
+ struct spi_adis16255_data *spiadis �ev_get_drvdata(&spi->dev);
+
+ /* turn 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);
+
+ dev_info(&spi->dev, "spi_adis16255 driver removed!\n");
+ return 0;
+}
+
+static struct spi_driver spi_adis16255_drv �
+ .driver �
+ .name �"spi_adis16255",
+ .owner �HIS_MODULE,
+ },
+ .probe �pi_adis16255_probe,
+ .remove � __devexit_p(spi_adis16255_remove),
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int __init spi_adis16255_init(void)
+{
+ return spi_register_driver(&spi_adis16255_drv);
+}
+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");