diff options
Diffstat (limited to 'drivers/hwmon/mag3110.c')
-rwxr-xr-x | drivers/hwmon/mag3110.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/drivers/hwmon/mag3110.c b/drivers/hwmon/mag3110.c new file mode 100755 index 000000000000..55f2114869cd --- /dev/null +++ b/drivers/hwmon/mag3110.c @@ -0,0 +1,570 @@ +/* + * + * Copyright (C) 2011-2012 Freescale Semiconductor, Inc. + * + * 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/interrupt.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/irq.h> +#include <linux/platform_device.h> +#include <linux/input-polldev.h> +#include <linux/hwmon.h> +#include <linux/input.h> +#include <linux/wait.h> +#include <linux/workqueue.h> + +#define MAG3110_DRV_NAME "mag3110" +#define MAG3110_ID 0xC4 +#define MAG3110_XYZ_DATA_LEN 6 +#define MAG3110_STATUS_ZYXDR 0x08 + +#define MAG3110_AC_MASK (0x01) +#define MAG3110_AC_OFFSET 0 +#define MAG3110_DR_MODE_MASK (0x7 << 5) +#define MAG3110_DR_MODE_OFFSET 5 +#define MAG3110_IRQ_USED 0 + +#define POLL_INTERVAL_MAX 500 +#define POLL_INTERVAL 100 +#define INT_TIMEOUT 1000 +/* register enum for mag3110 registers */ +enum { + MAG3110_DR_STATUS = 0x00, + MAG3110_OUT_X_MSB, + MAG3110_OUT_X_LSB, + MAG3110_OUT_Y_MSB, + MAG3110_OUT_Y_LSB, + MAG3110_OUT_Z_MSB, + MAG3110_OUT_Z_LSB, + MAG3110_WHO_AM_I, + + MAG3110_OFF_X_MSB, + MAG3110_OFF_X_LSB, + MAG3110_OFF_Y_MSB, + MAG3110_OFF_Y_LSB, + MAG3110_OFF_Z_MSB, + MAG3110_OFF_Z_LSB, + + MAG3110_DIE_TEMP, + + MAG3110_CTRL_REG1 = 0x10, + MAG3110_CTRL_REG2, +}; +enum { + MAG_STANDBY, + MAG_ACTIVED +}; +struct mag3110_data { + struct i2c_client *client; + struct input_polled_dev *poll_dev; + struct device *hwmon_dev; + wait_queue_head_t waitq; + bool data_ready; + u8 ctl_reg1; + int active; + int position; +}; +static short MAGHAL[8][3][3] = { + { {0, 1, 0}, {-1, 0, 0}, {0, 0, 1} }, + { {1, 0, 0}, {0, 1, 0}, {0, 0, 1} }, + { {0, -1, 0}, {1, 0, 0}, {0, 0, 1} }, + { {-1, 0, 0}, {0, -1, 0}, {0, 0, 1} }, + + { {0, 1, 0}, {1, 0, 0}, {0, 0, -1} }, + { {1, 0, 0}, {0, -1, 0}, {0, 0, -1} }, + { {0, -1, 0}, {-1, 0, 0}, {0, 0, -1} }, + { {-1, 0, 0}, {0, 1, 0}, {0, 0, -1} }, +}; + +static struct mag3110_data *mag3110_pdata; +/*! + * This function do one mag3110 register read. + */ +static DEFINE_MUTEX(mag3110_lock); +static int mag3110_adjust_position(short *x, short *y, short *z) +{ + short rawdata[3], data[3]; + int i, j; + int position = mag3110_pdata->position; + if (position < 0 || position > 7) + position = 0; + rawdata[0] = *x; + rawdata[1] = *y; + rawdata[2] = *z; + for (i = 0; i < 3; i++) { + data[i] = 0; + for (j = 0; j < 3; j++) + data[i] += rawdata[j] * MAGHAL[position][i][j]; + } + *x = data[0]; + *y = data[1]; + *z = data[2]; + return 0; +} + +static int mag3110_read_reg(struct i2c_client *client, u8 reg) +{ + return i2c_smbus_read_byte_data(client, reg); +} + +/*! + * This function do one mag3110 register write. + */ +static int mag3110_write_reg(struct i2c_client *client, u8 reg, char value) +{ + int ret; + + ret = i2c_smbus_write_byte_data(client, reg, value); + if (ret < 0) + dev_err(&client->dev, "i2c write failed\n"); + return ret; +} + +/*! + * This function do multiple mag3110 registers read. + */ +static int mag3110_read_block_data(struct i2c_client *client, u8 reg, + int count, u8 *addr) +{ + if (i2c_smbus_read_i2c_block_data(client, reg, count, addr) < count) { + dev_err(&client->dev, "i2c block read failed\n"); + return -1; + } + + return count; +} + +/* + * Initialization function + */ +static int mag3110_init_client(struct i2c_client *client) +{ + int val, ret; + + /* enable automatic resets */ + val = 0x80; + ret = mag3110_write_reg(client, MAG3110_CTRL_REG2, val); + + /* set default data rate to 10HZ */ + val = mag3110_read_reg(client, MAG3110_CTRL_REG1); + val |= (0x0 << MAG3110_DR_MODE_OFFSET); + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, val); + + return ret; +} + +/*************************************************************** +* +* read sensor data from mag3110 +* +***************************************************************/ +static int mag3110_read_data(short *x, short *y, short *z) +{ + struct mag3110_data *data; + int retry = 3; + u8 tmp_data[MAG3110_XYZ_DATA_LEN]; + int result; + if (!mag3110_pdata || mag3110_pdata->active == MAG_STANDBY) + return -EINVAL; + + data = mag3110_pdata; +#if MAG3110_IRQ_USED + if (!wait_event_interruptible_timeout + (data->waitq, data->data_ready != 0, + msecs_to_jiffies(INT_TIMEOUT))) { + dev_dbg(&data->client->dev, "interrupt not received\n"); + return -ETIME; + } +#else + do { + msleep(1); + result = i2c_smbus_read_byte_data(data->client, + MAG3110_DR_STATUS); + retry--; + } while (!(result & MAG3110_STATUS_ZYXDR) && retry > 0); + /* Clear data_ready flag after data is read out */ + if (retry == 0) { + return -EINVAL; + } +#endif + + data->data_ready = 0; + + if (mag3110_read_block_data(data->client, + MAG3110_OUT_X_MSB, MAG3110_XYZ_DATA_LEN, + tmp_data) < 0) + return -1; + + *x = ((tmp_data[0] << 8) & 0xff00) | tmp_data[1]; + *y = ((tmp_data[2] << 8) & 0xff00) | tmp_data[3]; + *z = ((tmp_data[4] << 8) & 0xff00) | tmp_data[5]; + + return 0; +} + +static void report_abs(void) +{ + struct input_dev *idev; + short x, y, z; + + mutex_lock(&mag3110_lock); + if (mag3110_read_data(&x, &y, &z) != 0) + goto out; + mag3110_adjust_position(&x, &y, &z); + idev = mag3110_pdata->poll_dev->input; + input_report_abs(idev, ABS_X, x); + input_report_abs(idev, ABS_Y, y); + input_report_abs(idev, ABS_Z, z); + input_sync(idev); +out: + mutex_unlock(&mag3110_lock); +} + +static void mag3110_dev_poll(struct input_polled_dev *dev) +{ + report_abs(); +} + +#if MAG3110_IRQ_USED +static irqreturn_t mag3110_irq_handler(int irq, void *dev_id) +{ + mag3110_pdata->data_ready = 1; + wake_up_interruptible(&mag3110_pdata->waitq); + + return IRQ_HANDLED; +} +#endif +static ssize_t mag3110_enable_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client; + int val; + mutex_lock(&mag3110_lock); + client = mag3110_pdata->client; + val = mag3110_read_reg(client, MAG3110_CTRL_REG1) & MAG3110_AC_MASK; + + mutex_unlock(&mag3110_lock); + return sprintf(buf, "%d\n", val); +} + +static ssize_t mag3110_enable_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client; + int reg, ret, enable; + u8 tmp_data[MAG3110_XYZ_DATA_LEN]; + + enable = simple_strtoul(buf, NULL, 10); + mutex_lock(&mag3110_lock); + client = mag3110_pdata->client; + reg = mag3110_read_reg(client, MAG3110_CTRL_REG1); + if (enable && mag3110_pdata->active == MAG_STANDBY) { + reg |= MAG3110_AC_MASK; + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, reg); + if (!ret) + mag3110_pdata->active = MAG_ACTIVED; + } else if (!enable && mag3110_pdata->active == MAG_ACTIVED) { + reg &= ~MAG3110_AC_MASK; + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, reg); + if (!ret) + mag3110_pdata->active = MAG_STANDBY; + } + + if (mag3110_pdata->active == MAG_ACTIVED) { + msleep(100); + /* Read out MSB data to clear interrupt flag automatically */ + mag3110_read_block_data(client, MAG3110_OUT_X_MSB, + MAG3110_XYZ_DATA_LEN, tmp_data); + } + mutex_unlock(&mag3110_lock); + return count; +} + +static DEVICE_ATTR(enable, S_IWUSR | S_IRUGO, + mag3110_enable_show, mag3110_enable_store); + +static ssize_t mag3110_dr_mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client; + int val; + + client = mag3110_pdata->client; + val = (mag3110_read_reg(client, MAG3110_CTRL_REG1) + & MAG3110_DR_MODE_MASK) >> MAG3110_DR_MODE_OFFSET; + + return sprintf(buf, "%d\n", val); +} + +static ssize_t mag3110_dr_mode_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client; + int reg, ret; + unsigned long val; + + /* This must be done when mag3110 is disabled */ + if ((strict_strtoul(buf, 10, &val) < 0) || (val > 7)) + return -EINVAL; + + client = mag3110_pdata->client; + reg = mag3110_read_reg(client, MAG3110_CTRL_REG1) & + ~MAG3110_DR_MODE_MASK; + reg |= (val << MAG3110_DR_MODE_OFFSET); + /* MAG3110_CTRL_REG1 bit 5-7: data rate mode */ + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, reg); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR(dr_mode, S_IWUSR | S_IRUGO, + mag3110_dr_mode_show, mag3110_dr_mode_store); + +static ssize_t mag3110_position_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int val; + mutex_lock(&mag3110_lock); + val = mag3110_pdata->position; + mutex_unlock(&mag3110_lock); + return sprintf(buf, "%d\n", val); +} + +static ssize_t mag3110_position_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int position; + position = simple_strtoul(buf, NULL, 10); + mutex_lock(&mag3110_lock); + mag3110_pdata->position = position; + mutex_unlock(&mag3110_lock); + return count; +} + +static DEVICE_ATTR(position, S_IWUSR | S_IRUGO, + mag3110_position_show, mag3110_position_store); + +static struct attribute *mag3110_attributes[] = { + &dev_attr_enable.attr, + &dev_attr_dr_mode.attr, + &dev_attr_position.attr, + NULL +}; + +static const struct attribute_group mag3110_attr_group = { + .attrs = mag3110_attributes, +}; + +static int __devinit mag3110_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter; + struct input_dev *idev; + struct mag3110_data *data; + int ret = 0; + + adapter = to_i2c_adapter(client->dev.parent); + if (!i2c_check_functionality(adapter, + I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK)) + return -EIO; + + dev_info(&client->dev, "check mag3110 chip ID\n"); + ret = mag3110_read_reg(client, MAG3110_WHO_AM_I); + + if (MAG3110_ID != ret) { + dev_err(&client->dev, + "read chip ID 0x%x is not equal to 0x%x!\n", ret, + MAG3110_ID); + return -EINVAL; + } + data = kzalloc(sizeof(struct mag3110_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + data->client = client; + i2c_set_clientdata(client, data); + /* Init queue */ + init_waitqueue_head(&data->waitq); + + data->hwmon_dev = hwmon_device_register(&client->dev); + if (IS_ERR(data->hwmon_dev)) { + dev_err(&client->dev, "hwmon register failed!\n"); + ret = PTR_ERR(data->hwmon_dev); + goto error_rm_dev_sysfs; + } + + /*input poll device register */ + data->poll_dev = input_allocate_polled_device(); + if (!data->poll_dev) { + dev_err(&client->dev, "alloc poll device failed!\n"); + ret = -ENOMEM; + goto error_rm_hwmon_dev; + } + data->poll_dev->poll = mag3110_dev_poll; + data->poll_dev->poll_interval = POLL_INTERVAL; + data->poll_dev->poll_interval_max = POLL_INTERVAL_MAX; + idev = data->poll_dev->input; + idev->name = MAG3110_DRV_NAME; + idev->id.bustype = BUS_I2C; + idev->evbit[0] = BIT_MASK(EV_ABS); + input_set_abs_params(idev, ABS_X, -15000, 15000, 0, 0); + input_set_abs_params(idev, ABS_Y, -15000, 15000, 0, 0); + input_set_abs_params(idev, ABS_Z, -15000, 15000, 0, 0); + ret = input_register_polled_device(data->poll_dev); + if (ret) { + dev_err(&client->dev, "register poll device failed!\n"); + goto error_free_poll_dev; + } + + /*create device group in sysfs as user interface */ + ret = sysfs_create_group(&idev->dev.kobj, &mag3110_attr_group); + if (ret) { + dev_err(&client->dev, "create device file failed!\n"); + ret = -EINVAL; + goto error_rm_poll_dev; + } + /* set irq type to edge rising */ +#if MAG3110_IRQ_USED + ret = request_irq(client->irq, mag3110_irq_handler, + IRQF_TRIGGER_RISING, client->dev.driver->name, idev); + if (ret < 0) { + dev_err(&client->dev, "failed to register irq %d!\n", + client->irq); + goto error_rm_dev_sysfs; + } +#endif + /* Initialize mag3110 chip */ + mag3110_init_client(client); + mag3110_pdata = data; + mag3110_pdata->active = MAG_STANDBY; + mag3110_pdata->position = *(int *)client->dev.platform_data; + dev_info(&client->dev, "mag3110 is probed\n"); + return 0; +error_rm_dev_sysfs: + sysfs_remove_group(&client->dev.kobj, &mag3110_attr_group); +error_rm_poll_dev: + input_unregister_polled_device(data->poll_dev); +error_free_poll_dev: + input_free_polled_device(data->poll_dev); +error_rm_hwmon_dev: + hwmon_device_unregister(data->hwmon_dev); + + kfree(data); + mag3110_pdata = NULL; + + return ret; +} + +static int __devexit mag3110_remove(struct i2c_client *client) +{ + struct mag3110_data *data; + int ret; + + data = i2c_get_clientdata(client); + + data->ctl_reg1 = mag3110_read_reg(client, MAG3110_CTRL_REG1); + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, + data->ctl_reg1 & ~MAG3110_AC_MASK); + + free_irq(client->irq, data); + input_unregister_polled_device(data->poll_dev); + input_free_polled_device(data->poll_dev); + hwmon_device_unregister(data->hwmon_dev); + sysfs_remove_group(&client->dev.kobj, &mag3110_attr_group); + kfree(data); + mag3110_pdata = NULL; + + return ret; +} + +#ifdef CONFIG_PM +static int mag3110_suspend(struct i2c_client *client, pm_message_t mesg) +{ + int ret = 0; + struct mag3110_data *data = i2c_get_clientdata(client); + if (data->active == MAG_ACTIVED) { + data->ctl_reg1 = mag3110_read_reg(client, MAG3110_CTRL_REG1); + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, + data->ctl_reg1 & ~MAG3110_AC_MASK); + } + return ret; +} + +static int mag3110_resume(struct i2c_client *client) +{ + int ret = 0; + u8 tmp_data[MAG3110_XYZ_DATA_LEN]; + struct mag3110_data *data = i2c_get_clientdata(client); + if (data->active == MAG_ACTIVED) { + ret = mag3110_write_reg(client, MAG3110_CTRL_REG1, + data->ctl_reg1); + + if (data->ctl_reg1 & MAG3110_AC_MASK) { + /* Read out MSB data to clear interrupt flag automatically */ + mag3110_read_block_data(client, MAG3110_OUT_X_MSB, + MAG3110_XYZ_DATA_LEN, tmp_data); + } + } + return ret; +} + +#else +#define mag3110_suspend NULL +#define mag3110_resume NULL +#endif /* CONFIG_PM */ + +static const struct i2c_device_id mag3110_id[] = { + {MAG3110_DRV_NAME, 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, mag3110_id); +static struct i2c_driver mag3110_driver = { + .driver = {.name = MAG3110_DRV_NAME, + .owner = THIS_MODULE,}, + .suspend = mag3110_suspend, + .resume = mag3110_resume, + .probe = mag3110_probe, + .remove = __devexit_p(mag3110_remove), + .id_table = mag3110_id, +}; + +static int __init mag3110_init(void) +{ + return i2c_add_driver(&mag3110_driver); +} + +static void __exit mag3110_exit(void) +{ + i2c_del_driver(&mag3110_driver); +} + +module_init(mag3110_init); +module_exit(mag3110_exit); +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("Freescale mag3110 3-axis magnetometer driver"); +MODULE_LICENSE("GPL"); |