--- /dev/null
+/*
+ * drivers/i2c/chips/ak8973.c - ak8973 compass driver
+ *
+ * Copyright (C) 2008 viral wang <viralwang@gmail.com>
+ *
+ * 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; version 2 of the License.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/miscdevice.h>
+#include <asm/gpio.h>
+#include <asm/uaccess.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/workqueue.h>
+#include <linux/freezer.h>
+#include "ak8973.h"
+#include<linux/earlysuspend.h>
+
+#define DEBUG 0
+#define MAX_FAILURE_COUNT 3
+
+static struct i2c_client *this_client;
+
+struct akm8973_data {
+ struct input_dev *input_dev;
+ struct work_struct work;
+#ifdef CONFIG_HAS_EARLYSUSPEND
+ struct early_suspend early_suspend_akm;
+#endif
+};
+
+/* Addresses to scan -- protected by sense_data_mutex */
+static char sense_data[RBUFF_SIZE + 1];
+static struct mutex sense_data_mutex;
+#define AKM8973_RETRY_COUNT 10
+static DECLARE_WAIT_QUEUE_HEAD(data_ready_wq);
+static DECLARE_WAIT_QUEUE_HEAD(open_wq);
+
+static atomic_t data_ready;
+static atomic_t open_count;
+static atomic_t open_flag;
+static atomic_t reserve_open_flag;
+
+static atomic_t m_flag;
+static atomic_t a_flag;
+static atomic_t t_flag;
+static atomic_t mv_flag;
+
+static int failure_count = 0;
+
+static short akmd_delay = 0;
+#ifdef CONFIG_HAS_EARLYSUSPEND
+static atomic_t suspend_flag = ATOMIC_INIT(0);
+#endif
+
+static int AKI2C_RxData(char *rxData, int length)
+{
+ uint8_t loop_i;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = this_client->addr,
+ .flags = 0,
+ .len = 1,
+ .buf = rxData,
+ },
+ {
+ .addr = this_client->addr,
+ .flags = I2C_M_RD,
+ .len = length,
+ .buf = rxData,
+ },
+ };
+
+ for (loop_i = 0; loop_i < AKM8973_RETRY_COUNT; loop_i++) {
+ if (i2c_transfer(this_client->adapter, msgs, 2) > 0) {
+ break;
+ }
+ mdelay(10);
+ }
+
+ if (loop_i >= AKM8973_RETRY_COUNT) {
+ printk(KERN_ERR "%s retry over %d\n", __func__, AKM8973_RETRY_COUNT);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int AKI2C_TxData(char *txData, int length)
+{
+ uint8_t loop_i;
+ struct i2c_msg msg[] = {
+ {
+ .addr = this_client->addr,
+ .flags = 0,
+ .len = length,
+ .buf = txData,
+ },
+ };
+
+ for (loop_i = 0; loop_i < AKM8973_RETRY_COUNT; loop_i++) {
+ if (i2c_transfer(this_client->adapter, msg, 1) > 0) {
+ break;
+ }
+ mdelay(10);
+ }
+
+ if (loop_i >= AKM8973_RETRY_COUNT) {
+ printk(KERN_ERR "%s retry over %d\n", __func__, AKM8973_RETRY_COUNT);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int AKECS_StartMeasure(void)
+{
+ char buffer[2];
+
+ /* Set measure mode */
+ buffer[0] = AKECS_REG_MS1;
+ buffer[1] = AKECS_MODE_MEASURE;
+
+ /* Set data */
+ return AKI2C_TxData(buffer, 2);
+}
+
+static int AKECS_PowerDown(void)
+{
+ char buffer[2];
+ int ret;
+
+ /* Set powerdown mode */
+ buffer[0] = AKECS_REG_MS1;
+ buffer[1] = AKECS_MODE_POWERDOWN;
+ /* Set data */
+ ret = AKI2C_TxData(buffer, 2);
+ if (ret < 0)
+ return ret;
+
+ /* Dummy read for clearing INT pin */
+ buffer[0] = AKECS_REG_TMPS;
+ /* Read data */
+ ret = AKI2C_RxData(buffer, 1);
+ if (ret < 0)
+ return ret;
+ return ret;
+}
+
+static int AKECS_StartE2PRead(void)
+{
+ char buffer[2];
+
+ /* Set measure mode */
+ buffer[0] = AKECS_REG_MS1;
+ buffer[1] = AKECS_MODE_E2P_READ;
+ /* Set data */
+ return AKI2C_TxData(buffer, 2);
+}
+
+static int AKECS_GetData(void)
+{
+ char buffer[RBUFF_SIZE + 1];
+ int ret;
+
+ memset(buffer, 0, RBUFF_SIZE + 1);
+ buffer[0] = AKECS_REG_ST;
+ ret = AKI2C_RxData(buffer, RBUFF_SIZE+1);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&sense_data_mutex);
+ memcpy(sense_data, buffer, sizeof(buffer));
+ atomic_set(&data_ready, 1);
+ wake_up(&data_ready_wq);
+ mutex_unlock(&sense_data_mutex);
+
+ return 0;
+}
+
+static int AKECS_SetMode(char mode)
+{
+ int ret;
+
+ switch (mode) {
+ case AKECS_MODE_MEASURE:
+ ret = AKECS_StartMeasure();
+ break;
+ case AKECS_MODE_E2P_READ:
+ ret = AKECS_StartE2PRead();
+ break;
+ case AKECS_MODE_POWERDOWN:
+ ret = AKECS_PowerDown();
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* wait at least 300us after changing mode */
+ msleep(1);
+ return ret;
+}
+
+static int AKECS_TransRBuff(char *rbuf, int size)
+{
+ wait_event_interruptible_timeout(data_ready_wq,
+ atomic_read(&data_ready), 1000);
+ if (!atomic_read(&data_ready)) {
+ #ifdef CONFIG_HAS_EARLYSUSPEND
+ if (!atomic_read(&suspend_flag)) {
+ printk(KERN_ERR
+ "AKM8973 AKECS_TransRBUFF: Data not ready\n");
+ failure_count++;
+ if (failure_count >= MAX_FAILURE_COUNT) {
+ printk(KERN_ERR
+ "AKM8973 AKECS_TransRBUFF: successive %d failure.\n",
+ failure_count);
+ atomic_set(&open_flag, -1);
+ wake_up(&open_wq);
+ failure_count = 0;
+ }
+ }
+ #endif
+ return -1;
+ }
+
+ mutex_lock(&sense_data_mutex);
+ memcpy(&rbuf[1], &sense_data[1], size);
+ atomic_set(&data_ready, 0);
+ mutex_unlock(&sense_data_mutex);
+
+ failure_count = 0;
+ return 0;
+}
+
+
+static void AKECS_Report_Value(short *rbuf)
+{
+ struct akm8973_data *data = i2c_get_clientdata(this_client);
+#if DEBUG
+ printk(KERN_INFO"AKECS_Report_Value: yaw = %d, pitch = %d, roll = %d\n", rbuf[0],
+ rbuf[1], rbuf[2]);
+ printk(KERN_INFO" tmp = %d, m_stat= %d, g_stat=%d\n", rbuf[3],
+ rbuf[4], rbuf[5]);
+ printk(KERN_INFO" G_Sensor: x = %d LSB, y = %d LSB, z = %d LSB\n",
+ rbuf[6], rbuf[7], rbuf[8]);
+#endif
+ /* Report magnetic sensor information */
+ if (atomic_read(&m_flag)) {
+ input_report_abs(data->input_dev, ABS_RX, rbuf[0]);
+ input_report_abs(data->input_dev, ABS_RY, rbuf[1]);
+ input_report_abs(data->input_dev, ABS_RZ, rbuf[2]);
+ input_report_abs(data->input_dev, ABS_RUDDER, rbuf[4]);
+ }
+
+ /* Report acceleration sensor information */
+ if (atomic_read(&a_flag)) {
+ input_report_abs(data->input_dev, ABS_X, rbuf[6]);
+ input_report_abs(data->input_dev, ABS_Y, rbuf[7]);
+ input_report_abs(data->input_dev, ABS_Z, rbuf[8]);
+ input_report_abs(data->input_dev, ABS_WHEEL, rbuf[5]);
+ }
+
+ /* Report temperature information */
+ if (atomic_read(&t_flag))
+ input_report_abs(data->input_dev, ABS_THROTTLE, rbuf[3]);
+
+ if (atomic_read(&mv_flag)) {
+ input_report_abs(data->input_dev, ABS_HAT0X, rbuf[9]);
+ input_report_abs(data->input_dev, ABS_HAT0Y, rbuf[10]);
+ input_report_abs(data->input_dev, ABS_BRAKE, rbuf[11]);
+ }
+
+ input_sync(data->input_dev);
+}
+
+static int AKECS_GetOpenStatus(void)
+{
+ wait_event_interruptible(open_wq, (atomic_read(&open_flag) != 0));
+ return atomic_read(&open_flag);
+}
+
+static int AKECS_GetCloseStatus(void)
+{
+ wait_event_interruptible(open_wq, (atomic_read(&open_flag) <= 0));
+ return atomic_read(&open_flag);
+}
+
+static void AKECS_CloseDone(void)
+{
+ atomic_set(&m_flag, 1);
+ atomic_set(&a_flag, 1);
+ atomic_set(&t_flag, 1);
+ atomic_set(&mv_flag, 1);
+}
+
+static int akm_aot_open(struct inode *inode, struct file *file)
+{
+ int ret = -1;
+ if (atomic_cmpxchg(&open_count, 0, 1) == 0) {
+ if (atomic_cmpxchg(&open_flag, 0, 1) == 0) {
+ atomic_set(&reserve_open_flag, 1);
+ wake_up(&open_wq);
+ ret = 0;
+ }
+ }
+ return ret;
+}
+
+static int akm_aot_release(struct inode *inode, struct file *file)
+{
+ atomic_set(&reserve_open_flag, 0);
+ atomic_set(&open_flag, 0);
+ atomic_set(&open_count, 0);
+ wake_up(&open_wq);
+ return 0;
+}
+
+static int
+akm_aot_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ short flag;
+
+ switch (cmd) {
+ case ECS_IOCTL_APP_SET_MFLAG:
+ case ECS_IOCTL_APP_SET_AFLAG:
+ case ECS_IOCTL_APP_SET_TFLAG:
+ case ECS_IOCTL_APP_SET_MVFLAG:
+ if (copy_from_user(&flag, argp, sizeof(flag)))
+ return -EFAULT;
+ if (flag < 0 || flag > 1)
+ return -EINVAL;
+ break;
+ case ECS_IOCTL_APP_SET_DELAY:
+ if (copy_from_user(&flag, argp, sizeof(flag)))
+ return -EFAULT;
+ break;
+ default:
+ break;
+ }
+
+ switch (cmd) {
+ case ECS_IOCTL_APP_SET_MFLAG:
+ atomic_set(&m_flag, flag);
+ break;
+ case ECS_IOCTL_APP_GET_MFLAG:
+ flag = atomic_read(&m_flag);
+ break;
+ case ECS_IOCTL_APP_SET_AFLAG:
+ atomic_set(&a_flag, flag);
+ break;
+ case ECS_IOCTL_APP_GET_AFLAG:
+ flag = atomic_read(&a_flag);
+ break;
+ case ECS_IOCTL_APP_SET_TFLAG:
+ atomic_set(&t_flag, flag);
+ break;
+ case ECS_IOCTL_APP_GET_TFLAG:
+ flag = atomic_read(&t_flag);
+ break;
+ case ECS_IOCTL_APP_SET_MVFLAG:
+ atomic_set(&mv_flag, flag);
+ break;
+ case ECS_IOCTL_APP_GET_MVFLAG:
+ flag = atomic_read(&mv_flag);
+ break;
+ case ECS_IOCTL_APP_SET_DELAY:
+ akmd_delay = flag;
+ break;
+ case ECS_IOCTL_APP_GET_DELAY:
+ flag = akmd_delay;
+ break;
+ default:
+ return -ENOTTY;
+ }
+
+ switch (cmd) {
+ case ECS_IOCTL_APP_GET_MFLAG:
+ case ECS_IOCTL_APP_GET_AFLAG:
+ case ECS_IOCTL_APP_GET_TFLAG:
+ case ECS_IOCTL_APP_GET_MVFLAG:
+ case ECS_IOCTL_APP_GET_DELAY:
+ if (copy_to_user(argp, &flag, sizeof(flag)))
+ return -EFAULT;
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int akmd_open(struct inode *inode, struct file *file)
+{
+ return nonseekable_open(inode, file);
+}
+
+static int akmd_release(struct inode *inode, struct file *file)
+{
+ AKECS_CloseDone();
+ return 0;
+}
+
+static int
+akmd_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+
+ void __user *argp = (void __user *)arg;
+
+ char msg[RBUFF_SIZE + 1], rwbuf[5];
+ int ret = -1, status;
+ short mode, value[12], delay;
+
+ switch (cmd) {
+ case ECS_IOCTL_WRITE:
+ case ECS_IOCTL_READ:
+ if (copy_from_user(&rwbuf, argp, sizeof(rwbuf)))
+ return -EFAULT;
+ break;
+ case ECS_IOCTL_SET_MODE:
+ if (copy_from_user(&mode, argp, sizeof(mode)))
+ return -EFAULT;
+ break;
+ case ECS_IOCTL_SET_YPR:
+ if (copy_from_user(&value, argp, sizeof(value)))
+ return -EFAULT;
+ break;
+ default:
+ break;
+ }
+
+ switch (cmd) {
+ case ECS_IOCTL_WRITE:
+ if (rwbuf[0] < 2)
+ return -EINVAL;
+ ret = AKI2C_TxData(&rwbuf[1], rwbuf[0]);
+ if (ret < 0)
+ return ret;
+ break;
+ case ECS_IOCTL_READ:
+ if (rwbuf[0] < 1)
+ return -EINVAL;
+ ret = AKI2C_RxData(&rwbuf[1], rwbuf[0]);
+ if (ret < 0)
+ return ret;
+ break;
+ case ECS_IOCTL_SET_MODE:
+ ret = AKECS_SetMode((char)mode);
+ if (ret < 0)
+ return ret;
+ break;
+ case ECS_IOCTL_GETDATA:
+ ret = AKECS_TransRBuff(msg, RBUFF_SIZE);
+ if (ret < 0)
+ return ret;
+ break;
+ case ECS_IOCTL_SET_YPR:
+ AKECS_Report_Value(value);
+ break;
+ case ECS_IOCTL_GET_OPEN_STATUS:
+ status = AKECS_GetOpenStatus();
+ break;
+ case ECS_IOCTL_GET_CLOSE_STATUS:
+ status = AKECS_GetCloseStatus();
+ break;
+ case ECS_IOCTL_GET_DELAY:
+ delay = akmd_delay;
+ break;
+ default:
+ return -ENOTTY;
+ }
+
+ switch (cmd) {
+ case ECS_IOCTL_READ:
+ if (copy_to_user(argp, &rwbuf, sizeof(rwbuf)))
+ return -EFAULT;
+ break;
+ case ECS_IOCTL_GETDATA:
+ if (copy_to_user(argp, &msg, sizeof(msg)))
+ return -EFAULT;
+ break;
+ case ECS_IOCTL_GET_OPEN_STATUS:
+ case ECS_IOCTL_GET_CLOSE_STATUS:
+ if (copy_to_user(argp, &status, sizeof(status)))
+ return -EFAULT;
+ break;
+ case ECS_IOCTL_GET_DELAY:
+ if (copy_to_user(argp, &delay, sizeof(delay)))
+ return -EFAULT;
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static void akm_work_func(struct work_struct *work)
+{
+ if (AKECS_GetData() < 0)
+ printk(KERN_ERR "AKM8973 akm_work_func: Get data failed\n");
+ enable_irq(this_client->irq);
+}
+
+static irqreturn_t akm8973_interrupt(int irq, void *dev_id)
+{
+ struct akm8973_data *data = dev_id;
+ disable_irq(this_client->irq);
+ schedule_work(&data->work);
+ return IRQ_HANDLED;
+}
+#ifdef CONFIG_HAS_EARLYSUSPEND
+static void akm8973_early_suspend(struct early_suspend *handler)
+{
+ atomic_set(&suspend_flag, 1);
+ atomic_set(&reserve_open_flag, atomic_read(&open_flag));
+ atomic_set(&open_flag, 0);
+ wake_up(&open_wq);
+ disable_irq(this_client->irq);
+}
+
+static void akm8973_early_resume(struct early_suspend *handler)
+{
+ enable_irq(this_client->irq);
+ atomic_set(&suspend_flag, 0);
+ atomic_set(&open_flag, atomic_read(&reserve_open_flag));
+ wake_up(&open_wq);
+}
+#endif
+static struct file_operations akmd_fops = {
+ .owner = THIS_MODULE,
+ .open = akmd_open,
+ .release = akmd_release,
+ .ioctl = akmd_ioctl,
+};
+
+static struct file_operations akm_aot_fops = {
+ .owner = THIS_MODULE,
+ .open = akm_aot_open,
+ .release = akm_aot_release,
+ .ioctl = akm_aot_ioctl,
+};
+
+
+static struct miscdevice akm_aot_device = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "akm8973_aot",
+ .fops = &akm_aot_fops,
+};
+
+
+static struct miscdevice akmd_device = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "akm8973_daemon",
+ .fops = &akmd_fops,
+};
+
+static ssize_t compass_reset_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int val;
+
+ val = -1;
+ sscanf(buf, "%u", &val);
+ if (val != 1)
+ return -EINVAL;
+
+ return count;
+}
+
+static DEVICE_ATTR(reset, 0644, NULL, compass_reset_store);
+
+int akm8973_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ struct akm8973_data *akm;
+ int err = 0;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ err = -ENODEV;
+ goto exit_check_functionality_failed;
+ }
+
+ akm = kzalloc(sizeof(struct akm8973_data), GFP_KERNEL);
+ if (!akm) {
+ err = -ENOMEM;
+ goto exit_alloc_data_failed;
+ }
+
+ INIT_WORK(&akm->work, akm_work_func);
+ i2c_set_clientdata(client, akm);
+
+ this_client = client;
+
+ err = AKECS_PowerDown();
+ if (err < 0) {
+ printk(KERN_ERR"AKM8973 akm8973_probe: set power down mode error\n");
+ goto exit_set_mode_failed;
+ }
+
+ err = request_irq(client->irq, akm8973_interrupt, IRQF_TRIGGER_HIGH,
+ "akm8973", akm);
+
+ if (err < 0) {
+ printk(KERN_ERR"AKM8973 akm8973_probe: request irq failed\n");
+ goto exit_irq_request_failed;
+ }
+
+ akm->input_dev = input_allocate_device();
+
+ if (!akm->input_dev) {
+ err = -ENOMEM;
+ printk(KERN_ERR
+ "AKM8973 akm8973_probe: Failed to allocate input device\n");
+ goto exit_input_dev_alloc_failed;
+ }
+
+ set_bit(EV_ABS, akm->input_dev->evbit);
+ /* yaw */
+ input_set_abs_params(akm->input_dev, ABS_RX, 0, 360, 0, 0);
+ /* pitch */
+ input_set_abs_params(akm->input_dev, ABS_RY, -180, 180, 0, 0);
+ /* roll */
+ input_set_abs_params(akm->input_dev, ABS_RZ, -90, 90, 0, 0);
+ /* x-axis acceleration */
+ input_set_abs_params(akm->input_dev, ABS_X, -1872, 1872, 0, 0);
+ /* y-axis acceleration */
+ input_set_abs_params(akm->input_dev, ABS_Y, -1872, 1872, 0, 0);
+ /* z-axis acceleration */
+ input_set_abs_params(akm->input_dev, ABS_Z, -1872, 1872, 0, 0);
+ /* temparature */
+ input_set_abs_params(akm->input_dev, ABS_THROTTLE, -30, 85, 0, 0);
+ /* status of magnetic sensor */
+ input_set_abs_params(akm->input_dev, ABS_RUDDER, -32768, 3, 0, 0);
+ /* status of acceleration sensor */
+ input_set_abs_params(akm->input_dev, ABS_WHEEL, -32768, 3, 0, 0);
+ /* step count */
+ input_set_abs_params(akm->input_dev, ABS_GAS, 0, 65535, 0, 0);
+ /* x-axis of raw magnetic vector */
+ input_set_abs_params(akm->input_dev, ABS_HAT0X, -2048, 2032, 0, 0);
+ /* y-axis of raw magnetic vector */
+ input_set_abs_params(akm->input_dev, ABS_HAT0Y, -2048, 2032, 0, 0);
+ /* z-axis of raw magnetic vector */
+ input_set_abs_params(akm->input_dev, ABS_BRAKE, -2048, 2032, 0, 0);
+
+ akm->input_dev->name = "compass";
+
+ err = input_register_device(akm->input_dev);
+
+ if (err) {
+ printk(KERN_ERR
+ "AKM8973 akm8973_probe: Unable to register input device: %s\n",
+ akm->input_dev->name);
+ goto exit_input_register_device_failed;
+ }
+
+ err = misc_register(&akmd_device);
+ if (err) {
+ printk(KERN_ERR "AKM8973 akm8973_probe: akmd_device register failed\n");
+ goto exit_misc_device_register_failed;
+ }
+
+ err = misc_register(&akm_aot_device);
+ if (err) {
+ printk(KERN_ERR
+ "AKM8973 akm8973_probe: akm_aot_device register failed\n");
+ goto exit_misc_device_register_failed;
+ }
+
+ mutex_init(&sense_data_mutex);
+
+ init_waitqueue_head(&data_ready_wq);
+ init_waitqueue_head(&open_wq);
+
+ /* As default, report all information */
+ atomic_set(&m_flag, 1);
+ atomic_set(&a_flag, 1);
+ atomic_set(&t_flag, 1);
+ atomic_set(&mv_flag, 1);
+#ifdef CONFIG_HAS_EARLYSUSPEND
+ akm->early_suspend_akm.suspend = akm8973_early_suspend;
+ akm->early_suspend_akm.resume = akm8973_early_resume;
+ register_early_suspend(&akm->early_suspend_akm);
+#endif
+ err = device_create_file(&client->dev, &dev_attr_reset);
+ if (err)
+ printk(KERN_ERR
+ "AKM8973 akm8973_probe: create dev_attr_reset failed\n");
+
+ return 0;
+
+exit_misc_device_register_failed:
+exit_input_register_device_failed:
+ input_free_device(akm->input_dev);
+exit_input_dev_alloc_failed:
+ free_irq(client->irq, akm);
+exit_irq_request_failed:
+exit_set_mode_failed:
+ kfree(akm);
+exit_alloc_data_failed:
+exit_check_functionality_failed:
+ return err;
+
+}
+
+static int akm8973_remove(struct i2c_client *client)
+{
+ struct akm8973_data *akm = i2c_get_clientdata(client);
+ free_irq(client->irq, akm);
+ input_unregister_device(akm->input_dev);
+ kfree(akm);
+ return 0;
+}
+static const struct i2c_device_id akm8973_id[] = {
+ { AKM8973_I2C_NAME, 0 },
+ { }
+};
+
+static struct i2c_driver akm8973_driver = {
+ .probe = akm8973_probe,
+ .remove = akm8973_remove,
+ .id_table = akm8973_id,
+ .driver = {
+ .name = AKM8973_I2C_NAME,
+ },
+};
+
+static int __init akm8973_init(void)
+{
+ printk(KERN_INFO "AKM8973 compass driver: init\n");
+ return i2c_add_driver(&akm8973_driver);
+}
+
+static void __exit akm8973_exit(void)
+{
+ i2c_del_driver(&akm8973_driver);
+}
+
+module_init(akm8973_init);
+module_exit(akm8973_exit);
+
+MODULE_AUTHOR("viral wang <viral_wang@htc.com>");
+MODULE_DESCRIPTION("AKM8973 compass driver");
+MODULE_LICENSE("GPL");
--- /dev/null
+/*
+ * A sensor driver for the magnetometer AK8975.
+ *
+ * Magnetic compass sensor driver for monitoring magnetic flux information.
+ *
+ * Copyright (c) 2010, NVIDIA Corporation.
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+
+#include <linux/gpio.h>
+
+#include "../iio.h"
+#include "magnet.h"
+
+/*
+ * Register definitions, as well as various shifts and masks to get at the
+ * individual fields of the registers.
+ */
+#define AK8975_REG_WIA 0x00
+#define AK8975_DEVICE_ID 0x48
+
+#define AK8975_REG_INFO 0x01
+
+#define AK8975_REG_ST1 0x02
+#define AK8975_REG_ST1_DRDY_SHIFT 0
+#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT)
+
+#define AK8975_REG_HXL 0x03
+#define AK8975_REG_HXH 0x04
+#define AK8975_REG_HYL 0x05
+#define AK8975_REG_HYH 0x06
+#define AK8975_REG_HZL 0x07
+#define AK8975_REG_HZH 0x08
+#define AK8975_REG_ST2 0x09
+#define AK8975_REG_ST2_DERR_SHIFT 2
+#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT)
+
+#define AK8975_REG_ST2_HOFL_SHIFT 3
+#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT)
+
+#define AK8975_REG_CNTL 0x0A
+#define AK8975_REG_CNTL_MODE_SHIFT 0
+#define AK8975_REG_CNTL_MODE_MASK (0xF << AK8975_REG_CNTL_MODE_SHIFT)
+#define AK8975_REG_CNTL_MODE_POWER_DOWN 0
+#define AK8975_REG_CNTL_MODE_ONCE 1
+#define AK8975_REG_CNTL_MODE_SELF_TEST 8
+#define AK8975_REG_CNTL_MODE_FUSE_ROM 0xF
+
+#define AK8975_REG_RSVC 0x0B
+#define AK8975_REG_ASTC 0x0C
+#define AK8975_REG_TS1 0x0D
+#define AK8975_REG_TS2 0x0E
+#define AK8975_REG_I2CDIS 0x0F
+#define AK8975_REG_ASAX 0x10
+#define AK8975_REG_ASAY 0x11
+#define AK8975_REG_ASAZ 0x12
+
+#define AK8975_MAX_REGS AK8975_REG_ASAZ
+
+/*
+ * Miscellaneous values.
+ */
+#define AK8975_MAX_CONVERSION_TRIAL 5
+#define AK8975_MAX_CONVERSION_TIMEOUT 500
+#define AK8975_CONVERSION_DONE_POLL_TIME 10
+
+/*
+ * Per-instance context data for the device.
+ */
+struct ak8975_data {
+ struct i2c_client *client;
+ struct iio_dev *indio_dev;
+ struct attribute_group attrs;
+ struct mutex lock;
+ u8 asa[3];
+ unsigned long mode;
+ u8 reg_cache[AK8975_MAX_REGS];
+ int eoc_gpio;
+ int eoc_irq;
+};
+
+/*
+ * Helper function to write to the I2C device's registers.
+ */
+static bool ak8975_write_data(struct i2c_client *client,
+ u8 reg, u8 val, u8 mask, u8 shift)
+{
+ u8 regval;
+ struct i2c_msg msg;
+ u8 w_data[2];
+ int ret = 0;
+
+ struct ak8975_data *data = i2c_get_clientdata(client);
+
+ regval = data->reg_cache[reg];
+ regval &= ~mask;
+ regval |= val << shift;
+
+ w_data[0] = reg;
+ w_data[1] = regval;
+
+ msg.addr = client->addr;
+ msg.flags = 0;
+ msg.len = 2;
+ msg.buf = w_data;
+
+ ret = i2c_transfer(client->adapter, &msg, 1);
+ if (ret < 0) {
+ dev_err(&client->dev, "Write to device fails status %x\n", ret);
+ return false;
+ }
+ data->reg_cache[reg] = regval;
+
+ return true;
+}
+
+/*
+ * Helper function to read a contiguous set of the I2C device's registers.
+ */
+static bool ak8975_read_data(struct i2c_client *client,
+ u8 reg, u8 length, u8 *buffer)
+{
+ struct i2c_msg msg[2];
+ u8 w_data[2];
+ int ret = 0;
+
+ w_data[0] = reg;
+
+ msg[0].addr = client->addr;
+ msg[0].flags = I2C_M_NOSTART; /* set repeated start and write */
+ msg[0].len = 1;
+ msg[0].buf = w_data;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = I2C_M_RD;
+ msg[1].len = length;
+ msg[1].buf = buffer;
+
+ ret = i2c_transfer(client->adapter, msg, 2);
+ if (ret < 0) {
+ dev_err(&client->dev, "Read from device fails\n");
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ * Perform some start-of-day setup, including reading the asa calibration
+ * values and caching them.
+ */
+static int ak8975_setup(struct i2c_client *client)
+{
+ struct ak8975_data *data = i2c_get_clientdata(client);
+ u8 device_id;
+ u8 buffer[3];
+ bool status;
+
+ /* Confirm that the device we're talking to is really an AK8975. */
+ status = ak8975_read_data(client, AK8975_REG_WIA, 1, &device_id);
+ if ((!status) || (device_id != AK8975_DEVICE_ID)) {
+ dev_err(&client->dev, "Device ak8975 not found\n");
+ return -ENODEV;
+ }
+
+ /* Write the fused rom access mode. */
+ status = ak8975_write_data(client, AK8975_REG_CNTL, AK8975_REG_CNTL_MODE_FUSE_ROM, AK8975_REG_CNTL_MODE_MASK, AK8975_REG_CNTL_MODE_SHIFT);
+ if (!status) {
+ dev_err(&client->dev, "Error in setting fuse access mode\n");
+ return false;
+ }
+
+ /* Get asa data and store in the device data. */
+ status = ak8975_read_data(client, AK8975_REG_ASAX, 3, buffer);
+ if (!status) {
+ dev_err(&client->dev, "Not able to read asa data\n");
+ return -ENODEV;
+ }
+
+ data->asa[0] = buffer[0] & 0xFF;
+ data->asa[1] = buffer[1] & 0xFF;
+ data->asa[2] = buffer[2] & 0xFF;
+
+ return 0;
+}
+
+/*
+ * Shows the device's mode. 0 = off, 1 = on.
+ */
+static ssize_t show_mode(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ak8975_data *data = indio_dev->dev_data;
+
+ return sprintf(buf, "%lu\n", data->mode);
+}
+
+/*
+ * Sets the device's mode. 0 = off, 1 = on. The device's mode must be on
+ * for the magn raw attributes to be available.
+ */
+static ssize_t store_mode(struct device *dev, struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ak8975_data *data = indio_dev->dev_data;
+ struct i2c_client *client = data->client;
+ unsigned long oval;
+ bool status;
+
+ /* Convert mode string and do some basic sanity checking on it.
+ only 0 or 1 are valid. */
+ if (strict_strtol(buf, 10, &oval))
+ return -EINVAL;
+
+ if ((oval < 0) || (oval > 1)) {
+ dev_err(dev, "mode value is not supported\n");
+ return -EINVAL;
+ }
+
+ mutex_lock(&data->lock);
+
+ /* Write the mode to the device. */
+ if (data->mode != oval) {
+ status = ak8975_write_data(client, AK8975_REG_CNTL, (u8)oval, AK8975_REG_CNTL_MODE_MASK, AK8975_REG_CNTL_MODE_SHIFT);
+ if (!status) {
+ dev_err(&client->dev, "Error in setting mode\n");
+ mutex_unlock(&data->lock);
+ return -EINVAL;
+ }
+ data->mode = oval;
+ }
+
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+/*
+ * Emits the ASA sensitivity adjustment value for the x, y, or z axis.
+ * These ASA values are read from the sensor device at start of day, and
+ * cached in the device context struct.
+ */
+static ssize_t show_calibscale(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ak8975_data *data = indio_dev->dev_data;
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(devattr);
+
+ if (!data) {
+ dev_err(dev, "No device found\n");
+ return -ENODEV;
+ }
+
+ return sprintf(buf, "%d\n", data->asa[this_attr->address]);
+}
+
+/*
+ * Emits the raw flux value for the x, y, or z axis.
+ *
+ * Adjusting the flux value with the sensitivity adjustment value should be
+ * done via the following formula:
+ *
+ * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
+ *
+ * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
+ * is the resultant adjusted value.
+ */
+static ssize_t show_raw(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ak8975_data *data = indio_dev->dev_data;
+ struct i2c_client *client = data->client;
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(devattr);
+ u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT;
+ u16 meas_reg;
+ s16 raw;
+ u8 read_status;
+ bool status;
+ int state;
+
+ /* Set up the device for taking a sample. */
+ status = ak8975_write_data(client, AK8975_REG_CNTL, AK8975_REG_CNTL_MODE_ONCE, AK8975_REG_CNTL_MODE_MASK, AK8975_REG_CNTL_MODE_SHIFT);
+ if (!status) {
+ dev_err(&client->dev, "Error in setting operating mode\n");
+ return false;
+ }
+
+ /* Wait for the conversion to complete. */
+ while (timeout_ms) {
+ msleep(AK8975_CONVERSION_DONE_POLL_TIME);
+ state = (gpio_get_value(data->eoc_gpio) ? 1 : 0);
+ if (state)
+ break;
+ timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
+ }
+ if (!timeout_ms) {
+ dev_err(&client->dev, "Conversion timeout happend\n");
+ return false;
+ }
+
+ status = ak8975_read_data(client, AK8975_REG_ST1, 1, &read_status);
+ if (!status) {
+ dev_err(&client->dev, "Error in reading ST1\n");
+ return false;
+ }
+
+ if (read_status & AK8975_REG_ST1_DRDY_MASK) {
+ status = ak8975_read_data(client, AK8975_REG_ST2, 1, &read_status);
+ if (!status) {
+ dev_err(&client->dev, "Error in reading ST2\n");
+ return false;
+ }
+ if (read_status & (AK8975_REG_ST2_DERR_MASK | AK8975_REG_ST2_HOFL_MASK)) {
+ dev_err(&client->dev, "ST2 status error 0x%x\n",
+ read_status);
+ return false;
+ }
+ }
+
+ /* Read the flux value from the appropriate register
+ (the register is specified in the iio device attributes). */
+ status = ak8975_read_data(client, this_attr->address, 2,
+ (u8 *)&meas_reg);
+ if (!status) {
+ dev_err(&client->dev, "Read axis data fails\n");
+ return false;
+ }
+
+ /* Endian conversion of the measured values */
+ raw = (s16) (le16_to_cpu(meas_reg));
+
+ return sprintf(buf, "%d\n", raw);
+}
+
+static IIO_DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, show_mode, store_mode, 0);
+static IIO_DEVICE_ATTR(magn_x_calibscale, S_IRUGO, show_calibscale, NULL, 0);
+static IIO_DEVICE_ATTR(magn_y_calibscale, S_IRUGO, show_calibscale, NULL, 1);
+static IIO_DEVICE_ATTR(magn_z_calibscale, S_IRUGO, show_calibscale, NULL, 2);
+static IIO_DEV_ATTR_MAGN_X(show_raw, AK8975_REG_HXL);
+static IIO_DEV_ATTR_MAGN_Y(show_raw, AK8975_REG_HYL);
+static IIO_DEV_ATTR_MAGN_Z(show_raw, AK8975_REG_HZL);
+
+static struct attribute *ak8975_attr[] = {
+ &iio_dev_attr_mode.dev_attr.attr,
+ &iio_dev_attr_magn_x_calibscale.dev_attr.attr,
+ &iio_dev_attr_magn_y_calibscale.dev_attr.attr,
+ &iio_dev_attr_magn_z_calibscale.dev_attr.attr,
+ &iio_dev_attr_magn_x_raw.dev_attr.attr,
+ &iio_dev_attr_magn_y_raw.dev_attr.attr,
+ &iio_dev_attr_magn_z_raw.dev_attr.attr,
+ NULL
+};
+
+static struct attribute_group ak8975_attr_group = {
+ .attrs = ak8975_attr,
+};
+
+static int ak8975_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct ak8975_data *data;
+ int err;
+
+ /* Allocate our device context. */
+ data = kzalloc(sizeof(struct ak8975_data), GFP_KERNEL);
+ if (!data) {
+ dev_err(&client->dev, "Memory allocation fails\n");
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ i2c_set_clientdata(client, data);
+ data->client = client;
+
+ mutex_init(&data->lock);
+
+ /* Grab and set up the supplied GPIO. */
+ data->eoc_irq = client->irq;
+ data->eoc_gpio = irq_to_gpio(client->irq);
+
+ err = gpio_request(data->eoc_gpio, "ak_8975");
+ if (err < 0) {
+ dev_err(&client->dev, "failed to request GPIO %d, error %d\n",
+ data->eoc_gpio, err);
+ goto exit_free;
+ }
+
+ err = gpio_direction_input(data->eoc_gpio);
+ if (err < 0) {
+ dev_err(&client->dev, "Failed to configure input direction for GPIO %d, error %d\n", data->eoc_gpio, err);
+ gpio_free(data->eoc_gpio);
+ goto exit_gpio;
+ }
+
+ /* Perform some basic start-of-day setup of the device. */
+ err = ak8975_setup(client);
+ if (err < 0) {
+ dev_err(&client->dev, "AK8975 initialization fails\n");
+ goto exit_gpio;
+ }
+
+ /* Register with IIO */
+ data->indio_dev = iio_allocate_device();
+ if (data->indio_dev == NULL) {
+ err = -ENOMEM;
+ goto exit_gpio;
+ }
+
+ data->indio_dev->dev.parent = &client->dev;
+ data->indio_dev->attrs = &ak8975_attr_group;
+ data->indio_dev->dev_data = (void *)(data);
+ data->indio_dev->driver_module = THIS_MODULE;
+ data->indio_dev->modes = INDIO_DIRECT_MODE;
+
+ err = iio_device_register(data->indio_dev);
+ if (err < 0)
+ goto exit_free_iio;
+
+ return 0;
+
+exit_free_iio:
+ iio_free_device(data->indio_dev);
+exit_gpio:
+ gpio_free(data->eoc_gpio);
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int ak8975_remove(struct i2c_client *client)
+{
+ struct ak8975_data *data = i2c_get_clientdata(client);
+
+ iio_device_unregister(data->indio_dev);
+ iio_free_device(data->indio_dev);
+
+ gpio_free(data->eoc_gpio);
+
+ kfree(data);
+
+ return 0;
+}
+
+static const struct i2c_device_id ak8975_id[] = {
+ {"ak8975", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, ak8975_id);
+
+static struct i2c_driver ak8975_driver = {
+ .driver = {
+ .name = "ak8975",
+ },
+ .probe = ak8975_probe,
+ .remove = __devexit_p(ak8975_remove),
+ .id_table = ak8975_id,
+};
+
+static int __init ak8975_init(void)
+{
+ return i2c_add_driver(&ak8975_driver);
+}
+
+static void __exit ak8975_exit(void)
+{
+ i2c_del_driver(&ak8975_driver);
+}
+
+module_init(ak8975_init);
+module_exit(ak8975_exit);
+
+MODULE_AUTHOR("Laxman Dewangan <ldewangan [at] nvidia>");
+MODULE_DESCRIPTION("AK8975 magnetometer driver");
+MODULE_LICENSE("GPL");
projects / firefly-linux-kernel-4.4.55.git / commitdiff