/* * lis3lv02d.c - ST LIS3LV02DL accelerometer driver * * Copyright (C) 2007-2008 Yan Burman * Copyright (C) 2008 Eric Piel * Copyright (C) 2008-2009 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. */ struct lis3lv02d lis3_dev = { .misc_wait = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait), }; EXPORT_SYMBOL_GPL(lis3_dev); static s16 lis3lv02d_read_8(struct lis3lv02d *lis3, int reg) { s8 lo; if (lis3->read(lis3, reg, &lo) < 0) return 0; return lo; } static s16 lis3lv02d_read_16(struct lis3lv02d *lis3, int reg) { u8 lo, hi; lis3->read(lis3, reg - 1, &lo); lis3->read(lis3, reg, &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 * @lis3: pointer to the device struct * @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(struct lis3lv02d *lis3, int *x, int *y, int *z) { int position[3]; position[0] = lis3_dev.read_data(lis3, OUTX); position[1] = lis3_dev.read_data(lis3, OUTY); position[2] = lis3_dev.read_data(lis3, OUTZ); *x = lis3lv02d_get_axis(lis3_dev.ac.x, position); *y = lis3lv02d_get_axis(lis3_dev.ac.y, position); *z = lis3lv02d_get_axis(lis3_dev.ac.z, position); } void lis3lv02d_poweroff(struct lis3lv02d *lis3) { lis3_dev.is_on = 0; } EXPORT_SYMBOL_GPL(lis3lv02d_poweroff); void lis3lv02d_poweron(struct lis3lv02d *lis3) { lis3_dev.is_on = 1; lis3_dev.init(lis3); } 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 lis3lv02d *dev) { mutex_lock(&dev->lock); dev->usage++; if (dev->usage == 1) { if (!dev->is_on) lis3lv02d_poweron(dev); } 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 lis3lv02d *dev) { mutex_lock(&dev->lock); dev->usage--; if (dev->usage == 0) lis3lv02d_poweroff(dev); mutex_unlock(&dev->lock); } static irqreturn_t lis302dl_interrupt(int irq, void *dummy) { /* * Be careful: on some HP laptops the bios force DD when on battery and * the lid is closed. This leads to interrupts as soon as a little move * is done. */ atomic_inc(&lis3_dev.count); wake_up_interruptible(&lis3_dev.misc_wait); kill_fasync(&lis3_dev.async_queue, SIGIO, POLL_IN); return IRQ_HANDLED; } static int lis3lv02d_misc_open(struct inode *inode, struct file *file) { int ret; if (test_and_set_bit(0, &lis3_dev.misc_opened)) return -EBUSY; /* already open */ atomic_set(&lis3_dev.count, 0); /* * The sensor can generate interrupts for free-fall and direction * detection (distinguishable with FF_WU_SRC and DD_SRC) but to keep * the things simple and _fast_ we activate it only for free-fall, so * no need to read register (very slow with ACPI). For the same reason, * we forbid shared interrupts. * * IRQF_TRIGGER_RISING seems pointless on HP laptops because the * io-apic is not configurable (and generates a warning) but I keep it * in case of support for other hardware. */ ret = request_irq(lis3_dev.irq, lis302dl_interrupt, IRQF_TRIGGER_RISING, DRIVER_NAME, &lis3_dev); if (ret) { clear_bit(0, &lis3_dev.misc_opened); printk(KERN_ERR DRIVER_NAME ": IRQ%d allocation failed\n", lis3_dev.irq); return -EBUSY; } lis3lv02d_increase_use(&lis3_dev); printk("lis3: registered interrupt %d\n", lis3_dev.irq); return 0; } static int lis3lv02d_misc_release(struct inode *inode, struct file *file) { fasync_helper(-1, file, 0, &lis3_dev.async_queue); lis3lv02d_decrease_use(&lis3_dev); free_irq(lis3_dev.irq, &lis3_dev); clear_bit(0, &lis3_dev.misc_opened); /* release the device */ return 0; } static ssize_t lis3lv02d_misc_read(struct file *file, char __user *buf, size_t count, loff_t *pos) { DECLARE_WAITQUEUE(wait, current); u32 data; unsigned char byte_data; ssize_t retval = 1; if (count < 1) return -EINVAL; add_wait_queue(&lis3_dev.misc_wait, &wait); while (true) { set_current_state(TASK_INTERRUPTIBLE); data = atomic_xchg(&lis3_dev.count, 0); if (data) break; if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto out; } if (signal_pending(current)) { retval = -ERESTARTSYS; goto out; } schedule(); } if (data < 255) byte_data = data; else byte_data = 255; /* make sure we are not going into copy_to_user() with * TASK_INTERRUPTIBLE state */ set_current_state(TASK_RUNNING); if (copy_to_user(buf, &byte_data, sizeof(byte_data))) retval = -EFAULT; out: __set_current_state(TASK_RUNNING); remove_wait_queue(&lis3_dev.misc_wait, &wait); return retval; } static unsigned int lis3lv02d_misc_poll(struct file *file, poll_table *wait) { poll_wait(file, &lis3_dev.misc_wait, wait); if (atomic_read(&lis3_dev.count)) return POLLIN | POLLRDNORM; return 0; } static int lis3lv02d_misc_fasync(int fd, struct file *file, int on) { return fasync_helper(fd, file, on, &lis3_dev.async_queue); } static const struct file_operations lis3lv02d_misc_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .read = lis3lv02d_misc_read, .open = lis3lv02d_misc_open, .release = lis3lv02d_misc_release, .poll = lis3lv02d_misc_poll, .fasync = lis3lv02d_misc_fasync, }; static struct miscdevice lis3lv02d_misc_device = { .minor = MISC_DYNAMIC_MINOR, .name = "freefall", .fops = &lis3lv02d_misc_fops, }; /** * 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(&lis3_dev, &x, &y, &z); input_report_abs(lis3_dev.idev, ABS_X, x - lis3_dev.xcalib); input_report_abs(lis3_dev.idev, ABS_Y, y - lis3_dev.ycalib); input_report_abs(lis3_dev.idev, ABS_Z, z - lis3_dev.zcalib); input_sync(lis3_dev.idev); try_to_freeze(); msleep_interruptible(MDPS_POLL_INTERVAL); } return 0; } static int lis3lv02d_joystick_open(struct input_dev *input) { lis3lv02d_increase_use(&lis3_dev); lis3_dev.kthread = kthread_run(lis3lv02d_joystick_kthread, NULL, "klis3lv02d"); if (IS_ERR(lis3_dev.kthread)) { lis3lv02d_decrease_use(&lis3_dev); return PTR_ERR(lis3_dev.kthread); } return 0; } static void lis3lv02d_joystick_close(struct input_dev *input) { kthread_stop(lis3_dev.kthread); lis3lv02d_decrease_use(&lis3_dev); } static inline void lis3lv02d_calibrate_joystick(void) { lis3lv02d_get_xyz(&lis3_dev, &lis3_dev.xcalib, &lis3_dev.ycalib, &lis3_dev.zcalib); } int lis3lv02d_joystick_enable(void) { int err; if (lis3_dev.idev) return -EINVAL; lis3_dev.idev = input_allocate_device(); if (!lis3_dev.idev) return -ENOMEM; lis3lv02d_calibrate_joystick(); lis3_dev.idev->name = "ST LIS3LV02DL Accelerometer"; lis3_dev.idev->phys = DRIVER_NAME "/input0"; lis3_dev.idev->id.bustype = BUS_HOST; lis3_dev.idev->id.vendor = 0; lis3_dev.idev->dev.parent = &lis3_dev.pdev->dev; lis3_dev.idev->open = lis3lv02d_joystick_open; lis3_dev.idev->close = lis3lv02d_joystick_close; set_bit(EV_ABS, lis3_dev.idev->evbit); input_set_abs_params(lis3_dev.idev, ABS_X, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3); input_set_abs_params(lis3_dev.idev, ABS_Y, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3); input_set_abs_params(lis3_dev.idev, ABS_Z, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3); err = input_register_device(lis3_dev.idev); if (err) { input_free_device(lis3_dev.idev); lis3_dev.idev = NULL; } return err; } EXPORT_SYMBOL_GPL(lis3lv02d_joystick_enable); void lis3lv02d_joystick_disable(void) { if (!lis3_dev.idev) return; misc_deregister(&lis3lv02d_misc_device); input_unregister_device(lis3_dev.idev); lis3_dev.idev = NULL; } EXPORT_SYMBOL_GPL(lis3lv02d_joystick_disable); /* Sysfs stuff */ static ssize_t lis3lv02d_position_show(struct device *dev, struct device_attribute *attr, char *buf) { int x, y, z; lis3lv02d_increase_use(&lis3_dev); lis3lv02d_get_xyz(&lis3_dev, &x, &y, &z); lis3lv02d_decrease_use(&lis3_dev); 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", lis3_dev.xcalib, lis3_dev.ycalib, lis3_dev.zcalib); } static ssize_t lis3lv02d_calibrate_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { lis3lv02d_increase_use(&lis3_dev); lis3lv02d_calibrate_joystick(); lis3lv02d_decrease_use(&lis3_dev); 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(&lis3_dev); lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl); lis3lv02d_decrease_use(&lis3_dev); 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 lis3lv02d *lis3) { lis3_dev.pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0); if (IS_ERR(lis3_dev.pdev)) return PTR_ERR(lis3_dev.pdev); return sysfs_create_group(&lis3_dev.pdev->dev.kobj, &lis3lv02d_attribute_group); } int lis3lv02d_remove_fs(void) { sysfs_remove_group(&lis3_dev.pdev->dev.kobj, &lis3lv02d_attribute_group); platform_device_unregister(lis3_dev.pdev); return 0; } EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs); /* * Initialise the accelerometer and the various subsystems. * Should be rather independant of the bus system. */ int lis3lv02d_init_device(struct lis3lv02d *dev) { dev->whoami = lis3lv02d_read_8(dev, WHO_AM_I); switch (dev->whoami) { case LIS_DOUBLE_ID: printk(KERN_INFO DRIVER_NAME ": 2-byte sensor found\n"); dev->read_data = lis3lv02d_read_16; dev->mdps_max_val = 2048; break; case LIS_SINGLE_ID: printk(KERN_INFO DRIVER_NAME ": 1-byte sensor found\n"); dev->read_data = lis3lv02d_read_8; dev->mdps_max_val = 128; break; default: printk(KERN_ERR DRIVER_NAME ": unknown sensor type 0x%X\n", lis3_dev.whoami); return -EINVAL; } mutex_init(&dev->lock); lis3lv02d_add_fs(dev); lis3lv02d_increase_use(dev); if (lis3lv02d_joystick_enable()) printk(KERN_ERR DRIVER_NAME ": joystick initialization failed\n"); printk("lis3_init_device: irq %d\n", dev->irq); /* bail if we did not get an IRQ from the bus layer */ if (!dev->irq) { printk(KERN_ERR DRIVER_NAME ": No IRQ. Disabling /dev/freefall\n"); goto out; } printk("lis3: registering device\n"); if (misc_register(&lis3lv02d_misc_device)) printk(KERN_ERR DRIVER_NAME ": misc_register failed\n"); out: lis3lv02d_decrease_use(dev); return 0; } EXPORT_SYMBOL_GPL(lis3lv02d_init_device); MODULE_DESCRIPTION("ST LIS3LV02Dx three-axis digital accelerometer driver"); MODULE_AUTHOR("Yan Burman, Eric Piel, Pavel Machek"); MODULE_LICENSE("GPL");