diff options
author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-05-02 11:48:07 -0700 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-05-02 11:48:07 -0700 |
commit | d210267741fb2a8b6d741d9040703683a39087f4 (patch) | |
tree | bfc1cdf7925644367cec4c82f2a5fb6d4c51a8eb /drivers/iio/industrialio-event.c | |
parent | 69964ea4c7b68c9399f7977aa5b9aa6539a6a98a (diff) | |
parent | 5bb196ad29c58c3e69dde8ed34b99a07c0719e7f (diff) |
Merge 3.4-rc5 into staging-next
This resolves the conflict in:
drivers/staging/vt6656/ioctl.c
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/industrialio-event.c')
-rw-r--r-- | drivers/iio/industrialio-event.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c new file mode 100644 index 00000000000..5fcf50b1ae5 --- /dev/null +++ b/drivers/iio/industrialio-event.c @@ -0,0 +1,453 @@ +/* Industrial I/O event handling + * + * Copyright (c) 2008 Jonathan Cameron + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * Based on elements of hwmon and input subsystems. + */ + +#include <linux/anon_inodes.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/kernel.h> +#include <linux/kfifo.h> +#include <linux/module.h> +#include <linux/poll.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/wait.h> +#include <linux/iio/iio.h> +#include "iio_core.h" +#include <linux/iio/sysfs.h> +#include <linux/iio/events.h> + +/** + * struct iio_event_interface - chrdev interface for an event line + * @wait: wait queue to allow blocking reads of events + * @det_events: list of detected events + * @dev_attr_list: list of event interface sysfs attribute + * @flags: file operations related flags including busy flag. + * @group: event interface sysfs attribute group + */ +struct iio_event_interface { + wait_queue_head_t wait; + DECLARE_KFIFO(det_events, struct iio_event_data, 16); + + struct list_head dev_attr_list; + unsigned long flags; + struct attribute_group group; +}; + +int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp) +{ + struct iio_event_interface *ev_int = indio_dev->event_interface; + struct iio_event_data ev; + int copied; + + /* Does anyone care? */ + spin_lock(&ev_int->wait.lock); + if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) { + + ev.id = ev_code; + ev.timestamp = timestamp; + + copied = kfifo_put(&ev_int->det_events, &ev); + if (copied != 0) + wake_up_locked_poll(&ev_int->wait, POLLIN); + } + spin_unlock(&ev_int->wait.lock); + + return 0; +} +EXPORT_SYMBOL(iio_push_event); + +/** + * iio_event_poll() - poll the event queue to find out if it has data + */ +static unsigned int iio_event_poll(struct file *filep, + struct poll_table_struct *wait) +{ + struct iio_event_interface *ev_int = filep->private_data; + unsigned int events = 0; + + poll_wait(filep, &ev_int->wait, wait); + + spin_lock(&ev_int->wait.lock); + if (!kfifo_is_empty(&ev_int->det_events)) + events = POLLIN | POLLRDNORM; + spin_unlock(&ev_int->wait.lock); + + return events; +} + +static ssize_t iio_event_chrdev_read(struct file *filep, + char __user *buf, + size_t count, + loff_t *f_ps) +{ + struct iio_event_interface *ev_int = filep->private_data; + unsigned int copied; + int ret; + + if (count < sizeof(struct iio_event_data)) + return -EINVAL; + + spin_lock(&ev_int->wait.lock); + if (kfifo_is_empty(&ev_int->det_events)) { + if (filep->f_flags & O_NONBLOCK) { + ret = -EAGAIN; + goto error_unlock; + } + /* Blocking on device; waiting for something to be there */ + ret = wait_event_interruptible_locked(ev_int->wait, + !kfifo_is_empty(&ev_int->det_events)); + if (ret) + goto error_unlock; + /* Single access device so no one else can get the data */ + } + + ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied); + +error_unlock: + spin_unlock(&ev_int->wait.lock); + + return ret ? ret : copied; +} + +static int iio_event_chrdev_release(struct inode *inode, struct file *filep) +{ + struct iio_event_interface *ev_int = filep->private_data; + + spin_lock(&ev_int->wait.lock); + __clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags); + /* + * In order to maintain a clean state for reopening, + * clear out any awaiting events. The mask will prevent + * any new __iio_push_event calls running. + */ + kfifo_reset_out(&ev_int->det_events); + spin_unlock(&ev_int->wait.lock); + + return 0; +} + +static const struct file_operations iio_event_chrdev_fileops = { + .read = iio_event_chrdev_read, + .poll = iio_event_poll, + .release = iio_event_chrdev_release, + .owner = THIS_MODULE, + .llseek = noop_llseek, +}; + +int iio_event_getfd(struct iio_dev *indio_dev) +{ + struct iio_event_interface *ev_int = indio_dev->event_interface; + int fd; + + if (ev_int == NULL) + return -ENODEV; + + spin_lock(&ev_int->wait.lock); + if (__test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) { + spin_unlock(&ev_int->wait.lock); + return -EBUSY; + } + spin_unlock(&ev_int->wait.lock); + fd = anon_inode_getfd("iio:event", + &iio_event_chrdev_fileops, ev_int, O_RDONLY); + if (fd < 0) { + spin_lock(&ev_int->wait.lock); + __clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags); + spin_unlock(&ev_int->wait.lock); + } + return fd; +} + +static const char * const iio_ev_type_text[] = { + [IIO_EV_TYPE_THRESH] = "thresh", + [IIO_EV_TYPE_MAG] = "mag", + [IIO_EV_TYPE_ROC] = "roc", + [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive", + [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive", +}; + +static const char * const iio_ev_dir_text[] = { + [IIO_EV_DIR_EITHER] = "either", + [IIO_EV_DIR_RISING] = "rising", + [IIO_EV_DIR_FALLING] = "falling" +}; + +static ssize_t iio_ev_state_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int ret; + bool val; + + ret = strtobool(buf, &val); + if (ret < 0) + return ret; + + ret = indio_dev->info->write_event_config(indio_dev, + this_attr->address, + val); + return (ret < 0) ? ret : len; +} + +static ssize_t iio_ev_state_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int val = indio_dev->info->read_event_config(indio_dev, + this_attr->address); + + if (val < 0) + return val; + else + return sprintf(buf, "%d\n", val); +} + +static ssize_t iio_ev_value_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int val, ret; + + ret = indio_dev->info->read_event_value(indio_dev, + this_attr->address, &val); + if (ret < 0) + return ret; + + return sprintf(buf, "%d\n", val); +} + +static ssize_t iio_ev_value_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + unsigned long val; + int ret; + + if (!indio_dev->info->write_event_value) + return -EINVAL; + + ret = strict_strtoul(buf, 10, &val); + if (ret) + return ret; + + ret = indio_dev->info->write_event_value(indio_dev, this_attr->address, + val); + if (ret < 0) + return ret; + + return len; +} + +static int iio_device_add_event_sysfs(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan) +{ + int ret = 0, i, attrcount = 0; + u64 mask = 0; + char *postfix; + if (!chan->event_mask) + return 0; + + for_each_set_bit(i, &chan->event_mask, sizeof(chan->event_mask)*8) { + postfix = kasprintf(GFP_KERNEL, "%s_%s_en", + iio_ev_type_text[i/IIO_EV_DIR_MAX], + iio_ev_dir_text[i%IIO_EV_DIR_MAX]); + if (postfix == NULL) { + ret = -ENOMEM; + goto error_ret; + } + if (chan->modified) + mask = IIO_MOD_EVENT_CODE(chan->type, 0, chan->channel, + i/IIO_EV_DIR_MAX, + i%IIO_EV_DIR_MAX); + else if (chan->differential) + mask = IIO_EVENT_CODE(chan->type, + 0, 0, + i%IIO_EV_DIR_MAX, + i/IIO_EV_DIR_MAX, + 0, + chan->channel, + chan->channel2); + else + mask = IIO_UNMOD_EVENT_CODE(chan->type, + chan->channel, + i/IIO_EV_DIR_MAX, + i%IIO_EV_DIR_MAX); + + ret = __iio_add_chan_devattr(postfix, + chan, + &iio_ev_state_show, + iio_ev_state_store, + mask, + 0, + &indio_dev->dev, + &indio_dev->event_interface-> + dev_attr_list); + kfree(postfix); + if (ret) + goto error_ret; + attrcount++; + postfix = kasprintf(GFP_KERNEL, "%s_%s_value", + iio_ev_type_text[i/IIO_EV_DIR_MAX], + iio_ev_dir_text[i%IIO_EV_DIR_MAX]); + if (postfix == NULL) { + ret = -ENOMEM; + goto error_ret; + } + ret = __iio_add_chan_devattr(postfix, chan, + iio_ev_value_show, + iio_ev_value_store, + mask, + 0, + &indio_dev->dev, + &indio_dev->event_interface-> + dev_attr_list); + kfree(postfix); + if (ret) + goto error_ret; + attrcount++; + } + ret = attrcount; +error_ret: + return ret; +} + +static inline void __iio_remove_event_config_attrs(struct iio_dev *indio_dev) +{ + struct iio_dev_attr *p, *n; + list_for_each_entry_safe(p, n, + &indio_dev->event_interface-> + dev_attr_list, l) { + kfree(p->dev_attr.attr.name); + kfree(p); + } +} + +static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev) +{ + int j, ret, attrcount = 0; + + INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list); + /* Dynically created from the channels array */ + for (j = 0; j < indio_dev->num_channels; j++) { + ret = iio_device_add_event_sysfs(indio_dev, + &indio_dev->channels[j]); + if (ret < 0) + goto error_clear_attrs; + attrcount += ret; + } + return attrcount; + +error_clear_attrs: + __iio_remove_event_config_attrs(indio_dev); + + return ret; +} + +static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev) +{ + int j; + + for (j = 0; j < indio_dev->num_channels; j++) + if (indio_dev->channels[j].event_mask != 0) + return true; + return false; +} + +static void iio_setup_ev_int(struct iio_event_interface *ev_int) +{ + INIT_KFIFO(ev_int->det_events); + init_waitqueue_head(&ev_int->wait); +} + +static const char *iio_event_group_name = "events"; +int iio_device_register_eventset(struct iio_dev *indio_dev) +{ + struct iio_dev_attr *p; + int ret = 0, attrcount_orig = 0, attrcount, attrn; + struct attribute **attr; + + if (!(indio_dev->info->event_attrs || + iio_check_for_dynamic_events(indio_dev))) + return 0; + + indio_dev->event_interface = + kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL); + if (indio_dev->event_interface == NULL) { + ret = -ENOMEM; + goto error_ret; + } + + iio_setup_ev_int(indio_dev->event_interface); + if (indio_dev->info->event_attrs != NULL) { + attr = indio_dev->info->event_attrs->attrs; + while (*attr++ != NULL) + attrcount_orig++; + } + attrcount = attrcount_orig; + if (indio_dev->channels) { + ret = __iio_add_event_config_attrs(indio_dev); + if (ret < 0) + goto error_free_setup_event_lines; + attrcount += ret; + } + + indio_dev->event_interface->group.name = iio_event_group_name; + indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1, + sizeof(indio_dev->event_interface->group.attrs[0]), + GFP_KERNEL); + if (indio_dev->event_interface->group.attrs == NULL) { + ret = -ENOMEM; + goto error_free_setup_event_lines; + } + if (indio_dev->info->event_attrs) + memcpy(indio_dev->event_interface->group.attrs, + indio_dev->info->event_attrs->attrs, + sizeof(indio_dev->event_interface->group.attrs[0]) + *attrcount_orig); + attrn = attrcount_orig; + /* Add all elements from the list. */ + list_for_each_entry(p, + &indio_dev->event_interface->dev_attr_list, + l) + indio_dev->event_interface->group.attrs[attrn++] = + &p->dev_attr.attr; + indio_dev->groups[indio_dev->groupcounter++] = + &indio_dev->event_interface->group; + + return 0; + +error_free_setup_event_lines: + __iio_remove_event_config_attrs(indio_dev); + kfree(indio_dev->event_interface); +error_ret: + + return ret; +} + +void iio_device_unregister_eventset(struct iio_dev *indio_dev) +{ + if (indio_dev->event_interface == NULL) + return; + __iio_remove_event_config_attrs(indio_dev); + kfree(indio_dev->event_interface->group.attrs); + kfree(indio_dev->event_interface); +} |