/* * lis3lv02d.c - ST LIS3LV02DL accelerometer driver * * Copyright (C) 2007-2008 Yan Burman * Copyright (C) 2008 Eric Piel * Copyright (C) 2008 Pavel Machek * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "lis3lv02d.h" #define DRIVER_NAME "lis3lv02d" /* joystick device poll interval in milliseconds */ #define MDPS_POLL_INTERVAL 50 /* * The sensor can also generate interrupts (DRDY) but it's pretty pointless * because their are generated even if the data do not change. So it's better * to keep the interrupt for the free-fall event. The values are updated at * 40Hz (at the lowest frequency), but as it can be pretty time consuming on * some low processor, we poll the sensor only at 20Hz... enough for the * joystick. */ /* Maximum value our axis may get for the input device (signed 12 bits) */ #define MDPS_MAX_VAL 2048 struct acpi_lis3lv02d adev; EXPORT_SYMBOL_GPL(adev); static int lis3lv02d_add_fs(struct acpi_device *device); static s16 lis3lv02d_read_16(acpi_handle handle, int reg) { u8 lo, hi; adev.read(handle, reg, &lo); adev.read(handle, reg + 1, &hi); /* In "12 bit right justified" mode, bit 6, bit 7, bit 8 = bit 5 */ return (s16)((hi << 8) | lo); } /** * lis3lv02d_get_axis - For the given axis, give the value converted * @axis: 1,2,3 - can also be negative * @hw_values: raw values returned by the hardware * * Returns the converted value. */ static inline int lis3lv02d_get_axis(s8 axis, int hw_values[3]) { if (axis > 0) return hw_values[axis - 1]; else return -hw_values[-axis - 1]; } /** * lis3lv02d_get_xyz - Get X, Y and Z axis values from the accelerometer * @handle: the handle to the device * @x: where to store the X axis value * @y: where to store the Y axis value * @z: where to store the Z axis value * * Note that 40Hz input device can eat up about 10% CPU at 800MHZ */ static void lis3lv02d_get_xyz(acpi_handle handle, int *x, int *y, int *z) { int position[3]; position[0] = lis3lv02d_read_16(handle, OUTX_L); position[1] = lis3lv02d_read_16(handle, OUTY_L); position[2] = lis3lv02d_read_16(handle, OUTZ_L); *x = lis3lv02d_get_axis(adev.ac.x, position); *y = lis3lv02d_get_axis(adev.ac.y, position); *z = lis3lv02d_get_axis(adev.ac.z, position); } void lis3lv02d_poweroff(acpi_handle handle) { adev.is_on = 0; /* disable X,Y,Z axis and power down */ adev.write(handle, CTRL_REG1, 0x00); } EXPORT_SYMBOL_GPL(lis3lv02d_poweroff); void lis3lv02d_poweron(acpi_handle handle) { u8 val; adev.is_on = 1; adev.init(handle); adev.write(handle, FF_WU_CFG, 0); /* * BDU: LSB and MSB values are not updated until both have been read. * So the value read will always be correct. * IEN: Interrupt for free-fall and DD, not for data-ready. */ adev.read(handle, CTRL_REG2, &val); val |= CTRL2_BDU | CTRL2_IEN; adev.write(handle, CTRL_REG2, val); } EXPORT_SYMBOL_GPL(lis3lv02d_poweron); /* * To be called before starting to use the device. It makes sure that the * device will always be on until a call to lis3lv02d_decrease_use(). Not to be * used from interrupt context. */ static void lis3lv02d_increase_use(struct acpi_lis3lv02d *dev) { mutex_lock(&dev->lock); dev->usage++; if (dev->usage == 1) { if (!dev->is_on) lis3lv02d_poweron(dev->device->handle); } mutex_unlock(&dev->lock); } /* * To be called whenever a usage of the device is stopped. * It will make sure to turn off the device when there is not usage. */ static void lis3lv02d_decrease_use(struct acpi_lis3lv02d *dev) { mutex_lock(&dev->lock); dev->usage--; if (dev->usage == 0) lis3lv02d_poweroff(dev->device->handle); mutex_unlock(&dev->lock); } /** * lis3lv02d_joystick_kthread - Kthread polling function * @data: unused - here to conform to threadfn prototype */ static int lis3lv02d_joystick_kthread(void *data) { int x, y, z; while (!kthread_should_stop()) { lis3lv02d_get_xyz(adev.device->handle, &x, &y, &z); input_report_abs(adev.idev, ABS_X, x - adev.xcalib); input_report_abs(adev.idev, ABS_Y, y - adev.ycalib); input_report_abs(adev.idev, ABS_Z, z - adev.zcalib); input_sync(adev.idev); try_to_freeze(); msleep_interruptible(MDPS_POLL_INTERVAL); } return 0; } static int lis3lv02d_joystick_open(struct input_dev *input) { lis3lv02d_increase_use(&adev); adev.kthread = kthread_run(lis3lv02d_joystick_kthread, NULL, "klis3lv02d"); if (IS_ERR(adev.kthread)) { lis3lv02d_decrease_use(&adev); return PTR_ERR(adev.kthread); } return 0; } static void lis3lv02d_joystick_close(struct input_dev *input) { kthread_stop(adev.kthread); lis3lv02d_decrease_use(&adev); } static inline void lis3lv02d_calibrate_joystick(void) { lis3lv02d_get_xyz(adev.device->handle, &adev.xcalib, &adev.ycalib, &adev.zcalib); } int lis3lv02d_joystick_enable(void) { int err; if (adev.idev) return -EINVAL; adev.idev = input_allocate_device(); if (!adev.idev) return -ENOMEM; lis3lv02d_calibrate_joystick(); adev.idev->name = "ST LIS3LV02DL Accelerometer"; adev.idev->phys = DRIVER_NAME "/input0"; adev.idev->id.bustype = BUS_HOST; adev.idev->id.vendor = 0; adev.idev->dev.parent = &adev.pdev->dev; adev.idev->open = lis3lv02d_joystick_open; adev.idev->close = lis3lv02d_joystick_close; set_bit(EV_ABS, adev.idev->evbit); input_set_abs_params(adev.idev, ABS_X, -MDPS_MAX_VAL, MDPS_MAX_VAL, 3, 3); input_set_abs_params(adev.idev, ABS_Y, -MDPS_MAX_VAL, MDPS_MAX_VAL, 3, 3); input_set_abs_params(adev.idev, ABS_Z, -MDPS_MAX_VAL, MDPS_MAX_VAL, 3, 3); err = input_register_device(adev.idev); if (err) { input_free_device(adev.idev); adev.idev = NULL; } return err; } EXPORT_SYMBOL_GPL(lis3lv02d_joystick_enable); void lis3lv02d_joystick_disable(void) { if (!adev.idev) return; input_unregister_device(adev.idev); adev.idev = NULL; } EXPORT_SYMBOL_GPL(lis3lv02d_joystick_disable); /* * Initialise the accelerometer and the various subsystems. * Should be rather independant of the bus system. */ int lis3lv02d_init_device(struct acpi_lis3lv02d *dev) { mutex_init(&dev->lock); lis3lv02d_add_fs(dev->device); lis3lv02d_increase_use(dev); if (lis3lv02d_joystick_enable()) printk(KERN_ERR DRIVER_NAME ": joystick initialization failed\n"); lis3lv02d_decrease_use(dev); return 0; } EXPORT_SYMBOL_GPL(lis3lv02d_init_device); /* Sysfs stuff */ static ssize_t lis3lv02d_position_show(struct device *dev, struct device_attribute *attr, char *buf) { int x, y, z; lis3lv02d_increase_use(&adev); lis3lv02d_get_xyz(adev.device->handle, &x, &y, &z); lis3lv02d_decrease_use(&adev); return sprintf(buf, "(%d,%d,%d)\n", x, y, z); } static ssize_t lis3lv02d_calibrate_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "(%d,%d,%d)\n", adev.xcalib, adev.ycalib, adev.zcalib); } static ssize_t lis3lv02d_calibrate_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { lis3lv02d_increase_use(&adev); lis3lv02d_calibrate_joystick(); lis3lv02d_decrease_use(&adev); return count; } /* conversion btw sampling rate and the register values */ static int lis3lv02dl_df_val[4] = {40, 160, 640, 2560}; static ssize_t lis3lv02d_rate_show(struct device *dev, struct device_attribute *attr, char *buf) { u8 ctrl; int val; lis3lv02d_increase_use(&adev); adev.read(adev.device->handle, CTRL_REG1, &ctrl); lis3lv02d_decrease_use(&adev); val = (ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4; return sprintf(buf, "%d\n", lis3lv02dl_df_val[val]); } static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL); static DEVICE_ATTR(calibrate, S_IRUGO|S_IWUSR, lis3lv02d_calibrate_show, lis3lv02d_calibrate_store); static DEVICE_ATTR(rate, S_IRUGO, lis3lv02d_rate_show, NULL); static struct attribute *lis3lv02d_attributes[] = { &dev_attr_position.attr, &dev_attr_calibrate.attr, &dev_attr_rate.attr, NULL }; static struct attribute_group lis3lv02d_attribute_group = { .attrs = lis3lv02d_attributes }; static int lis3lv02d_add_fs(struct acpi_device *device) { adev.pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0); if (IS_ERR(adev.pdev)) return PTR_ERR(adev.pdev); return sysfs_create_group(&adev.pdev->dev.kobj, &lis3lv02d_attribute_group); } int lis3lv02d_remove_fs(void) { sysfs_remove_group(&adev.pdev->dev.kobj, &lis3lv02d_attribute_group); platform_device_unregister(adev.pdev); return 0; } EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs); MODULE_DESCRIPTION("ST LIS3LV02Dx three-axis digital accelerometer driver"); MODULE_AUTHOR("Yan Burman and Eric Piel"); MODULE_LICENSE("GPL");