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![Tejun Heo](/assets/img/avatar_default.png)
Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
236 lines
6 KiB
C
236 lines
6 KiB
C
/*
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* kernel API
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*
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*
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* Copyright (C) 2005-2009 Rodolfo Giometti <giometti@linux.it>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/time.h>
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#include <linux/timex.h>
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#include <linux/spinlock.h>
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#include <linux/fs.h>
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#include <linux/pps_kernel.h>
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#include <linux/slab.h>
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#include "kc.h"
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/*
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* Local functions
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*/
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static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset)
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{
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ts->nsec += offset->nsec;
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while (ts->nsec >= NSEC_PER_SEC) {
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ts->nsec -= NSEC_PER_SEC;
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ts->sec++;
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}
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while (ts->nsec < 0) {
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ts->nsec += NSEC_PER_SEC;
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ts->sec--;
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}
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ts->sec += offset->sec;
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}
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static void pps_echo_client_default(struct pps_device *pps, int event,
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void *data)
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{
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dev_info(pps->dev, "echo %s %s\n",
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event & PPS_CAPTUREASSERT ? "assert" : "",
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event & PPS_CAPTURECLEAR ? "clear" : "");
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}
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/*
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* Exported functions
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*/
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/* pps_register_source - add a PPS source in the system
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* @info: the PPS info struct
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* @default_params: the default PPS parameters of the new source
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*
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* This function is used to add a new PPS source in the system. The new
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* source is described by info's fields and it will have, as default PPS
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* parameters, the ones specified into default_params.
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*
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* The function returns, in case of success, the PPS device. Otherwise NULL.
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*/
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struct pps_device *pps_register_source(struct pps_source_info *info,
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int default_params)
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{
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struct pps_device *pps;
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int err;
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/* Sanity checks */
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if ((info->mode & default_params) != default_params) {
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pr_err("%s: unsupported default parameters\n",
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info->name);
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err = -EINVAL;
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goto pps_register_source_exit;
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}
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if ((info->mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
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pr_err("%s: unspecified time format\n",
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info->name);
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err = -EINVAL;
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goto pps_register_source_exit;
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}
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/* Allocate memory for the new PPS source struct */
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pps = kzalloc(sizeof(struct pps_device), GFP_KERNEL);
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if (pps == NULL) {
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err = -ENOMEM;
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goto pps_register_source_exit;
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}
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/* These initializations must be done before calling idr_alloc()
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* in order to avoid reces into pps_event().
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*/
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pps->params.api_version = PPS_API_VERS;
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pps->params.mode = default_params;
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pps->info = *info;
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/* check for default echo function */
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if ((pps->info.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) &&
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pps->info.echo == NULL)
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pps->info.echo = pps_echo_client_default;
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init_waitqueue_head(&pps->queue);
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spin_lock_init(&pps->lock);
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/* Create the char device */
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err = pps_register_cdev(pps);
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if (err < 0) {
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pr_err("%s: unable to create char device\n",
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info->name);
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goto kfree_pps;
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}
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dev_info(pps->dev, "new PPS source %s\n", info->name);
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return pps;
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kfree_pps:
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kfree(pps);
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pps_register_source_exit:
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pr_err("%s: unable to register source\n", info->name);
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return NULL;
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}
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EXPORT_SYMBOL(pps_register_source);
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/* pps_unregister_source - remove a PPS source from the system
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* @pps: the PPS source
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*
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* This function is used to remove a previously registered PPS source from
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* the system.
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*/
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void pps_unregister_source(struct pps_device *pps)
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{
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pps_kc_remove(pps);
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pps_unregister_cdev(pps);
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/* don't have to kfree(pps) here because it will be done on
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* device destruction */
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}
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EXPORT_SYMBOL(pps_unregister_source);
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/* pps_event - register a PPS event into the system
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* @pps: the PPS device
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* @ts: the event timestamp
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* @event: the event type
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* @data: userdef pointer
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*
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* This function is used by each PPS client in order to register a new
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* PPS event into the system (it's usually called inside an IRQ handler).
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*
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* If an echo function is associated with the PPS device it will be called
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* as:
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* pps->info.echo(pps, event, data);
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*/
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void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
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void *data)
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{
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unsigned long flags;
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int captured = 0;
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struct pps_ktime ts_real = { .sec = 0, .nsec = 0, .flags = 0 };
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/* check event type */
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BUG_ON((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0);
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dev_dbg(pps->dev, "PPS event at %ld.%09ld\n",
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ts->ts_real.tv_sec, ts->ts_real.tv_nsec);
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timespec_to_pps_ktime(&ts_real, ts->ts_real);
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spin_lock_irqsave(&pps->lock, flags);
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/* Must call the echo function? */
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if ((pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)))
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pps->info.echo(pps, event, data);
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/* Check the event */
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pps->current_mode = pps->params.mode;
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if (event & pps->params.mode & PPS_CAPTUREASSERT) {
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/* We have to add an offset? */
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if (pps->params.mode & PPS_OFFSETASSERT)
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pps_add_offset(&ts_real,
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&pps->params.assert_off_tu);
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/* Save the time stamp */
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pps->assert_tu = ts_real;
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pps->assert_sequence++;
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dev_dbg(pps->dev, "capture assert seq #%u\n",
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pps->assert_sequence);
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captured = ~0;
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}
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if (event & pps->params.mode & PPS_CAPTURECLEAR) {
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/* We have to add an offset? */
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if (pps->params.mode & PPS_OFFSETCLEAR)
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pps_add_offset(&ts_real,
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&pps->params.clear_off_tu);
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/* Save the time stamp */
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pps->clear_tu = ts_real;
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pps->clear_sequence++;
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dev_dbg(pps->dev, "capture clear seq #%u\n",
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pps->clear_sequence);
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captured = ~0;
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}
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pps_kc_event(pps, ts, event);
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/* Wake up if captured something */
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if (captured) {
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pps->last_ev++;
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wake_up_interruptible_all(&pps->queue);
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kill_fasync(&pps->async_queue, SIGIO, POLL_IN);
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}
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spin_unlock_irqrestore(&pps->lock, flags);
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}
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EXPORT_SYMBOL(pps_event);
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