Files
nuttx/sched/clock/clock_settime.c
T
dongjiuzhu1 1c643b5cc3 sched/clock: support using CLOCKFD to call clock_gettime/settime
This patch implements POSIX-compliant CLOCKFD support, enabling user
applications to access dynamic PTP clocks through file descriptors
combined with clock_gettime() and clock_settime() system calls.

Key changes include:

1. CLOCKFD macro support:
   - Added CLOCKFD() macro in include/nuttx/clock.h
   - Allows encoding file descriptor into clockid_t: CLOCKFD(fd)
   - Enables accessing PTP clocks via: clock_gettime(CLOCKFD(fd), &ts)

2. clock_gettime() enhancements:
   - Modified sched/clock/clock_gettime.c to detect CLOCKFD clockids
   - Extracts file descriptor from clockid using CLOCKFD_TO_FD()
   - Validates file descriptor and calls file_ioctl() with PTP_CLOCK_GETTIME
   - Falls back to standard clock handling for non-CLOCKFD clockids

3. clock_settime() enhancements:
   - Modified sched/clock/clock_settime.c to support CLOCKFD clockids
   - Extracts file descriptor and validates accessibility
   - Issues PTP_CLOCK_SETTIME ioctl to underlying PTP clock device
   - Maintains backward compatibility with standard POSIX clocks

4. File descriptor validation:
   - Checks file descriptor validity using fs_getfilep()
   - Ensures proper reference counting with fs_putfilep()
   - Returns appropriate error codes (EINVAL, EBADF) on failures

5. Integration with PTP clock framework:
   - Seamlessly integrates with PTP clock driver's ioctl interface
   - Enables standard POSIX clock API usage for dynamic PTP clocks
   - No changes required to existing applications using standard clocks

Usage example:
  int fd = open("/dev/ptp0", O_RDONLY);
  struct timespec ts;
  clock_gettime(CLOCKFD(fd), &ts);  /* Get PTP clock time */
  clock_settime(CLOCKFD(fd), &ts);  /* Set PTP clock time */
  close(fd);

This implementation follows the Linux kernel's PTP clock model, providing
a familiar interface for developers working with PTP hardware.

Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
2025-12-30 10:22:09 -03:00

169 lines
4.3 KiB
C

/****************************************************************************
* sched/clock/clock_settime.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <time.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <sys/time.h>
#include <nuttx/arch.h>
#include <nuttx/fs/fs.h>
#include <nuttx/irq.h>
#include <nuttx/spinlock.h>
#include <nuttx/timers/ptp_clock.h>
#include "clock/clock.h"
#ifdef CONFIG_CLOCK_TIMEKEEPING
# include "clock/clock_timekeeping.h"
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
static void nxclock_set_realtime(FAR const struct timespec *tp)
{
#ifndef CONFIG_CLOCK_TIMEKEEPING
struct timespec bias;
irqstate_t flags;
# ifdef CONFIG_CLOCK_ADJTIME
const struct timeval zerodelta = {
0, 0
};
# endif
/* Interrupts are disabled here so that the in-memory time
* representation and the RTC setting will be as close as
* possible.
*/
/* Get the elapsed time since power up (in milliseconds). This is a
* bias value that we need to use to correct the base time.
*/
clock_systime_timespec(&bias);
flags = spin_lock_irqsave(&g_basetime_lock);
clock_timespec_subtract(tp, &bias, &g_basetime);
spin_unlock_irqrestore(&g_basetime_lock, flags);
/* Setup the RTC (lo- or high-res) */
# ifdef CONFIG_RTC
if (g_rtc_enabled)
{
up_rtc_settime(tp);
}
# endif
# ifdef CONFIG_CLOCK_ADJTIME
/* Cancel any ongoing adjustment */
adjtime(&zerodelta, NULL);
# endif
#else
clock_timekeeping_set_wall_time(tp);
#endif
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxclock_settime
*
* Description:
* Clock Functions based on POSIX APIs
*
* CLOCK_REALTIME - POSIX demands this to be present. This is the wall
* time clock.
*
****************************************************************************/
int nxclock_settime(clockid_t clock_id, FAR const struct timespec *tp)
{
int ret = -EINVAL;
if (tp == NULL || tp->tv_nsec < 0 || tp->tv_nsec >= 1000000000)
{
return ret;
}
if (clock_id == CLOCK_REALTIME)
{
nxclock_set_realtime(tp);
return 0;
}
#ifdef CONFIG_PTP_CLOCK
else if ((clock_id & CLOCK_MASK) == CLOCK_FD)
{
FAR struct file *filep;
ret = ptp_clockid_to_filep(clock_id, &filep);
if (ret < 0)
{
return ret;
}
ret = file_ioctl(filep, PTP_CLOCK_SETTIME, tp);
fs_putfilep(filep);
}
#endif
return ret;
}
/****************************************************************************
* Name: clock_settime
*
* Description:
* Clock Functions based on POSIX APIs
*
* CLOCK_REALTIME - POSIX demands this to be present. This is the wall
* time clock.
*
****************************************************************************/
int clock_settime(clockid_t clock_id, FAR const struct timespec *tp)
{
int ret;
ret = nxclock_settime(clock_id, tp);
if (ret < 0)
{
set_errno(-ret);
return ERROR;
}
return OK;
}