/* * PPS core file * * * Copyright (C) 2005-2009 Rodolfo Giometti * * 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include #include /* * Local variables */ static dev_t pps_devt; static struct class *pps_class; /* * Char device methods */ static unsigned int pps_cdev_poll(struct file *file, poll_table *wait) { struct pps_device *pps = file->private_data; poll_wait(file, &pps->queue, wait); return POLLIN | POLLRDNORM; } static int pps_cdev_fasync(int fd, struct file *file, int on) { struct pps_device *pps = file->private_data; return fasync_helper(fd, file, on, &pps->async_queue); } static long pps_cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct pps_device *pps = file->private_data; struct pps_kparams params; struct pps_fdata fdata; unsigned long ticks; void __user *uarg = (void __user *) arg; int __user *iuarg = (int __user *) arg; int err; switch (cmd) { case PPS_GETPARAMS: pr_debug("PPS_GETPARAMS: source %d\n", pps->id); /* Return current parameters */ err = copy_to_user(uarg, &pps->params, sizeof(struct pps_kparams)); if (err) return -EFAULT; break; case PPS_SETPARAMS: pr_debug("PPS_SETPARAMS: source %d\n", pps->id); /* Check the capabilities */ if (!capable(CAP_SYS_TIME)) return -EPERM; err = copy_from_user(¶ms, uarg, sizeof(struct pps_kparams)); if (err) return -EFAULT; if (!(params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) { pr_debug("capture mode unspecified (%x)\n", params.mode); return -EINVAL; } /* Check for supported capabilities */ if ((params.mode & ~pps->info.mode) != 0) { pr_debug("unsupported capabilities (%x)\n", params.mode); return -EINVAL; } spin_lock_irq(&pps->lock); /* Save the new parameters */ pps->params = params; /* Restore the read only parameters */ if ((params.mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) { /* section 3.3 of RFC 2783 interpreted */ pr_debug("time format unspecified (%x)\n", params.mode); pps->params.mode |= PPS_TSFMT_TSPEC; } if (pps->info.mode & PPS_CANWAIT) pps->params.mode |= PPS_CANWAIT; pps->params.api_version = PPS_API_VERS; spin_unlock_irq(&pps->lock); break; case PPS_GETCAP: pr_debug("PPS_GETCAP: source %d\n", pps->id); err = put_user(pps->info.mode, iuarg); if (err) return -EFAULT; break; case PPS_FETCH: pr_debug("PPS_FETCH: source %d\n", pps->id); err = copy_from_user(&fdata, uarg, sizeof(struct pps_fdata)); if (err) return -EFAULT; pps->go = 0; /* Manage the timeout */ if (fdata.timeout.flags & PPS_TIME_INVALID) err = wait_event_interruptible(pps->queue, pps->go); else { pr_debug("timeout %lld.%09d\n", (long long) fdata.timeout.sec, fdata.timeout.nsec); ticks = fdata.timeout.sec * HZ; ticks += fdata.timeout.nsec / (NSEC_PER_SEC / HZ); if (ticks != 0) { err = wait_event_interruptible_timeout( pps->queue, pps->go, ticks); if (err == 0) return -ETIMEDOUT; } } /* Check for pending signals */ if (err == -ERESTARTSYS) { pr_debug("pending signal caught\n"); return -EINTR; } /* Return the fetched timestamp */ spin_lock_irq(&pps->lock); fdata.info.assert_sequence = pps->assert_sequence; fdata.info.clear_sequence = pps->clear_sequence; fdata.info.assert_tu = pps->assert_tu; fdata.info.clear_tu = pps->clear_tu; fdata.info.current_mode = pps->current_mode; spin_unlock_irq(&pps->lock); err = copy_to_user(uarg, &fdata, sizeof(struct pps_fdata)); if (err) return -EFAULT; break; default: return -ENOTTY; break; } return 0; } static int pps_cdev_open(struct inode *inode, struct file *file) { struct pps_device *pps = container_of(inode->i_cdev, struct pps_device, cdev); int found; found = pps_get_source(pps->id) != 0; if (!found) return -ENODEV; file->private_data = pps; return 0; } static int pps_cdev_release(struct inode *inode, struct file *file) { struct pps_device *pps = file->private_data; /* Free the PPS source and wake up (possible) deregistration */ pps_put_source(pps); return 0; } /* * Char device stuff */ static const struct file_operations pps_cdev_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .poll = pps_cdev_poll, .fasync = pps_cdev_fasync, .unlocked_ioctl = pps_cdev_ioctl, .open = pps_cdev_open, .release = pps_cdev_release, }; int pps_register_cdev(struct pps_device *pps) { int err; pps->devno = MKDEV(MAJOR(pps_devt), pps->id); cdev_init(&pps->cdev, &pps_cdev_fops); pps->cdev.owner = pps->info.owner; err = cdev_add(&pps->cdev, pps->devno, 1); if (err) { printk(KERN_ERR "pps: %s: failed to add char device %d:%d\n", pps->info.name, MAJOR(pps_devt), pps->id); return err; } pps->dev = device_create(pps_class, pps->info.dev, pps->devno, NULL, "pps%d", pps->id); if (err) goto del_cdev; dev_set_drvdata(pps->dev, pps); pr_debug("source %s got cdev (%d:%d)\n", pps->info.name, MAJOR(pps_devt), pps->id); return 0; del_cdev: cdev_del(&pps->cdev); return err; } void pps_unregister_cdev(struct pps_device *pps) { device_destroy(pps_class, pps->devno); cdev_del(&pps->cdev); } /* * Module stuff */ static void __exit pps_exit(void) { class_destroy(pps_class); unregister_chrdev_region(pps_devt, PPS_MAX_SOURCES); } static int __init pps_init(void) { int err; pps_class = class_create(THIS_MODULE, "pps"); if (!pps_class) { printk(KERN_ERR "pps: failed to allocate class\n"); return -ENOMEM; } pps_class->dev_attrs = pps_attrs; err = alloc_chrdev_region(&pps_devt, 0, PPS_MAX_SOURCES, "pps"); if (err < 0) { printk(KERN_ERR "pps: failed to allocate char device region\n"); goto remove_class; } pr_info("LinuxPPS API ver. %d registered\n", PPS_API_VERS); pr_info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti " "\n", PPS_VERSION); return 0; remove_class: class_destroy(pps_class); return err; } subsys_initcall(pps_init); module_exit(pps_exit); MODULE_AUTHOR("Rodolfo Giometti "); MODULE_DESCRIPTION("LinuxPPS support (RFC 2783) - ver. " PPS_VERSION); MODULE_LICENSE("GPL");