pps: add kernel consumer support (717c0336) · Commits · e / devices / android_kernel_fairphone_FP4

Documentation/ioctl/ioctl-number.txt

+1 −1

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		@@ -247,7 +247,7 @@ Code Seq#(hex) Include File Comments
		'p' 40-7F linux/nvram.h
		'p' 80-9F linux/ppdev.h user-space parport
		<mailto:tim@cyberelk.net>
		'p' A1-A4 linux/pps.h LinuxPPS
		'p' A1-A5 linux/pps.h LinuxPPS
		<mailto:giometti@linux.it>
		'q' 00-1F linux/serio.h
		'q' 80-FF linux/telephony.h Internet PhoneJACK, Internet LineJACK

drivers/pps/Makefile

+1 −0

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		@@ -3,6 +3,7 @@
		#

		pps_core-y := pps.o kapi.o sysfs.o
		pps_core-$(CONFIG_NTP_PPS) += kc.o
		obj-$(CONFIG_PPS) := pps_core.o
		obj-y += clients/

drivers/pps/kapi.c

+6 −0

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		@@ -26,11 +26,14 @@
		#include <linux/init.h>
		#include <linux/sched.h>
		#include <linux/time.h>
		#include <linux/timex.h>
		#include <linux/spinlock.h>
		#include <linux/fs.h>
		#include <linux/pps_kernel.h>
		#include <linux/slab.h>

		#include "kc.h"

		/*
		* Local functions
		*/
		@@ -139,6 +142,7 @@ EXPORT_SYMBOL(pps_register_source);

		void pps_unregister_source(struct pps_device *pps)
		{
		pps_kc_remove(pps);
		pps_unregister_cdev(pps);

		/* don't have to kfree(pps) here because it will be done on
		@@ -211,6 +215,8 @@ void pps_event(struct pps_device pps, struct pps_event_time ts, int event,
		captured = ~0;
		}

		pps_kc_event(pps, ts, event);

		/* Wake up if captured something */
		if (captured) {
		pps->last_ev++;

drivers/pps/kc.c

0 → 100644

+122 −0

Original line number	Diff line number	Diff line
		/*
		* PPS kernel consumer API
		*
		* Copyright (C) 2009-2010 Alexander Gordeev <lasaine@lvk.cs.msu.su>
		*
		* 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.
		*/

		#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/device.h>
		#include <linux/init.h>
		#include <linux/spinlock.h>
		#include <linux/pps_kernel.h>

		#include "kc.h"

		/*
		* Global variables
		*/

		/* state variables to bind kernel consumer */
		DEFINE_SPINLOCK(pps_kc_hardpps_lock);
		/* PPS API (RFC 2783): current source and mode for kernel consumer */
		struct pps_device pps_kc_hardpps_dev; / unique pointer to device */
		int pps_kc_hardpps_mode; /* mode bits for kernel consumer */

		/* pps_kc_bind - control PPS kernel consumer binding
		* @pps: the PPS source
		* @bind_args: kernel consumer bind parameters
		*
		* This function is used to bind or unbind PPS kernel consumer according to
		* supplied parameters. Should not be called in interrupt context.
		*/
		int pps_kc_bind(struct pps_device pps, struct pps_bind_args bind_args)
		{
		/* Check if another consumer is already bound */
		spin_lock_irq(&pps_kc_hardpps_lock);

		if (bind_args->edge == 0)
		if (pps_kc_hardpps_dev == pps) {
		pps_kc_hardpps_mode = 0;
		pps_kc_hardpps_dev = NULL;
		spin_unlock_irq(&pps_kc_hardpps_lock);
		dev_info(pps->dev, "unbound kernel"
		" consumer\n");
		} else {
		spin_unlock_irq(&pps_kc_hardpps_lock);
		dev_err(pps->dev, "selected kernel consumer"
		" is not bound\n");
		return -EINVAL;
		}
		else
		if (pps_kc_hardpps_dev == NULL \|\|
		pps_kc_hardpps_dev == pps) {
		pps_kc_hardpps_mode = bind_args->edge;
		pps_kc_hardpps_dev = pps;
		spin_unlock_irq(&pps_kc_hardpps_lock);
		dev_info(pps->dev, "bound kernel consumer: "
		"edge=0x%x\n", bind_args->edge);
		} else {
		spin_unlock_irq(&pps_kc_hardpps_lock);
		dev_err(pps->dev, "another kernel consumer"
		" is already bound\n");
		return -EINVAL;
		}

		return 0;
		}

		/* pps_kc_remove - unbind kernel consumer on PPS source removal
		* @pps: the PPS source
		*
		* This function is used to disable kernel consumer on PPS source removal
		* if this source was bound to PPS kernel consumer. Can be called on any
		* source safely. Should not be called in interrupt context.
		*/
		void pps_kc_remove(struct pps_device *pps)
		{
		spin_lock_irq(&pps_kc_hardpps_lock);
		if (pps == pps_kc_hardpps_dev) {
		pps_kc_hardpps_mode = 0;
		pps_kc_hardpps_dev = NULL;
		spin_unlock_irq(&pps_kc_hardpps_lock);
		dev_info(pps->dev, "unbound kernel consumer"
		" on device removal\n");
		} else
		spin_unlock_irq(&pps_kc_hardpps_lock);
		}

		/* pps_kc_event - call hardpps() on PPS event
		* @pps: the PPS source
		* @ts: PPS event timestamp
		* @event: PPS event edge
		*
		* This function calls hardpps() when an event from bound PPS source occurs.
		*/
		void pps_kc_event(struct pps_device pps, struct pps_event_time ts,
		int event)
		{
		unsigned long flags;

		/* Pass some events to kernel consumer if activated */
		spin_lock_irqsave(&pps_kc_hardpps_lock, flags);
		if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode)
		hardpps(&ts->ts_real, &ts->ts_raw);
		spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags);
		}

drivers/pps/kc.h

0 → 100644

+46 −0

Original line number	Diff line number	Diff line
		/*
		* PPS kernel consumer API header
		*
		* Copyright (C) 2009-2010 Alexander Gordeev <lasaine@lvk.cs.msu.su>
		*
		* 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.
		*/

		#ifndef LINUX_PPS_KC_H
		#define LINUX_PPS_KC_H

		#include <linux/errno.h>
		#include <linux/pps_kernel.h>

		#ifdef CONFIG_NTP_PPS

		extern int pps_kc_bind(struct pps_device *pps,
		struct pps_bind_args *bind_args);
		extern void pps_kc_remove(struct pps_device *pps);
		extern void pps_kc_event(struct pps_device *pps,
		struct pps_event_time *ts, int event);


		#else /* CONFIG_NTP_PPS */

		static inline int pps_kc_bind(struct pps_device *pps,
		struct pps_bind_args *bind_args) { return -EOPNOTSUPP; }
		static inline void pps_kc_remove(struct pps_device *pps) {}
		static inline void pps_kc_event(struct pps_device *pps,
		struct pps_event_time *ts, int event) {}

		#endif /* CONFIG_NTP_PPS */

		#endif /* LINUX_PPS_KC_H */