511 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			511 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
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| /*
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|  * PTP 1588 clock support - character device implementation.
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|  *
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|  * Copyright (C) 2010 OMICRON electronics GmbH
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|  */
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| #include <linux/module.h>
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| #include <linux/posix-clock.h>
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| #include <linux/poll.h>
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| #include <linux/sched.h>
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| #include <linux/slab.h>
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| #include <linux/timekeeping.h>
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| 
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| #include <linux/nospec.h>
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| 
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| #include "ptp_private.h"
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| 
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| static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
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| 			       enum ptp_pin_function func, unsigned int chan)
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| {
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| 	struct ptp_clock_request rq;
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| 	int err = 0;
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| 
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| 	memset(&rq, 0, sizeof(rq));
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| 
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| 	switch (func) {
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| 	case PTP_PF_NONE:
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| 		break;
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| 	case PTP_PF_EXTTS:
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| 		rq.type = PTP_CLK_REQ_EXTTS;
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| 		rq.extts.index = chan;
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| 		err = ops->enable(ops, &rq, 0);
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| 		break;
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| 	case PTP_PF_PEROUT:
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| 		rq.type = PTP_CLK_REQ_PEROUT;
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| 		rq.perout.index = chan;
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| 		err = ops->enable(ops, &rq, 0);
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| 		break;
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| 	case PTP_PF_PHYSYNC:
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| 		break;
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| 	default:
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| 		return -EINVAL;
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| 	}
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| 
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| 	return err;
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| }
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| 
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| int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
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| 		    enum ptp_pin_function func, unsigned int chan)
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| {
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| 	struct ptp_clock_info *info = ptp->info;
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| 	struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
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| 	unsigned int i;
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| 
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| 	/* Check to see if any other pin previously had this function. */
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| 	for (i = 0; i < info->n_pins; i++) {
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| 		if (info->pin_config[i].func == func &&
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| 		    info->pin_config[i].chan == chan) {
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| 			pin1 = &info->pin_config[i];
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| 			break;
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| 		}
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| 	}
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| 	if (pin1 && i == pin)
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| 		return 0;
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| 
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| 	/* Check the desired function and channel. */
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| 	switch (func) {
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| 	case PTP_PF_NONE:
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| 		break;
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| 	case PTP_PF_EXTTS:
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| 		if (chan >= info->n_ext_ts)
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| 			return -EINVAL;
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| 		break;
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| 	case PTP_PF_PEROUT:
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| 		if (chan >= info->n_per_out)
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| 			return -EINVAL;
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| 		break;
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| 	case PTP_PF_PHYSYNC:
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| 		if (chan != 0)
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| 			return -EINVAL;
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| 		break;
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| 	default:
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| 		return -EINVAL;
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| 	}
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| 
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| 	if (info->verify(info, pin, func, chan)) {
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| 		pr_err("driver cannot use function %u and channel %u on pin %u\n",
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| 		       func, chan, pin);
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| 		return -EOPNOTSUPP;
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| 	}
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| 
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| 	/* Disable whatever function was previously assigned. */
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| 	if (pin1) {
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| 		ptp_disable_pinfunc(info, func, chan);
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| 		pin1->func = PTP_PF_NONE;
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| 		pin1->chan = 0;
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| 	}
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| 	ptp_disable_pinfunc(info, pin2->func, pin2->chan);
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| 	pin2->func = func;
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| 	pin2->chan = chan;
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| 
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| 	return 0;
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| }
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| 
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| int ptp_open(struct posix_clock *pc, fmode_t fmode)
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| {
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| 	return 0;
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| }
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| 
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| long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
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| {
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| 	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
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| 	struct ptp_sys_offset_extended *extoff = NULL;
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| 	struct ptp_sys_offset_precise precise_offset;
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| 	struct system_device_crosststamp xtstamp;
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| 	struct ptp_clock_info *ops = ptp->info;
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| 	struct ptp_sys_offset *sysoff = NULL;
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| 	struct ptp_system_timestamp sts;
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| 	struct ptp_clock_request req;
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| 	struct ptp_clock_caps caps;
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| 	struct ptp_clock_time *pct;
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| 	unsigned int i, pin_index;
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| 	struct ptp_pin_desc pd;
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| 	struct timespec64 ts;
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| 	int enable, err = 0;
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| 
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| 	switch (cmd) {
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| 
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| 	case PTP_CLOCK_GETCAPS:
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| 	case PTP_CLOCK_GETCAPS2:
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| 		memset(&caps, 0, sizeof(caps));
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| 
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| 		caps.max_adj = ptp->info->max_adj;
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| 		caps.n_alarm = ptp->info->n_alarm;
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| 		caps.n_ext_ts = ptp->info->n_ext_ts;
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| 		caps.n_per_out = ptp->info->n_per_out;
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| 		caps.pps = ptp->info->pps;
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| 		caps.n_pins = ptp->info->n_pins;
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| 		caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
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| 		caps.adjust_phase = ptp->info->adjphase != NULL &&
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| 				    ptp->info->getmaxphase != NULL;
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| 		if (caps.adjust_phase)
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| 			caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
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| 		if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
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| 			err = -EFAULT;
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| 		break;
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| 
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| 	case PTP_EXTTS_REQUEST:
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| 	case PTP_EXTTS_REQUEST2:
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| 		memset(&req, 0, sizeof(req));
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| 
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| 		if (copy_from_user(&req.extts, (void __user *)arg,
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| 				   sizeof(req.extts))) {
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| 			err = -EFAULT;
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| 			break;
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| 		}
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| 		if (cmd == PTP_EXTTS_REQUEST2) {
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| 			/* Tell the drivers to check the flags carefully. */
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| 			req.extts.flags |= PTP_STRICT_FLAGS;
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| 			/* Make sure no reserved bit is set. */
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| 			if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
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| 			    req.extts.rsv[0] || req.extts.rsv[1]) {
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| 				err = -EINVAL;
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| 				break;
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| 			}
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| 			/* Ensure one of the rising/falling edge bits is set. */
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| 			if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
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| 			    (req.extts.flags & PTP_EXTTS_EDGES) == 0) {
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| 				err = -EINVAL;
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| 				break;
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| 			}
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| 		} else if (cmd == PTP_EXTTS_REQUEST) {
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| 			req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
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| 			req.extts.rsv[0] = 0;
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| 			req.extts.rsv[1] = 0;
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| 		}
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| 		if (req.extts.index >= ops->n_ext_ts) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		req.type = PTP_CLK_REQ_EXTTS;
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| 		enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
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| 		if (mutex_lock_interruptible(&ptp->pincfg_mux))
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| 			return -ERESTARTSYS;
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| 		err = ops->enable(ops, &req, enable);
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| 		mutex_unlock(&ptp->pincfg_mux);
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| 		break;
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| 
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| 	case PTP_PEROUT_REQUEST:
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| 	case PTP_PEROUT_REQUEST2:
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| 		memset(&req, 0, sizeof(req));
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| 
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| 		if (copy_from_user(&req.perout, (void __user *)arg,
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| 				   sizeof(req.perout))) {
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| 			err = -EFAULT;
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| 			break;
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| 		}
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| 		if (cmd == PTP_PEROUT_REQUEST2) {
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| 			struct ptp_perout_request *perout = &req.perout;
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| 
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| 			if (perout->flags & ~PTP_PEROUT_VALID_FLAGS) {
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| 				err = -EINVAL;
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| 				break;
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| 			}
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| 			/*
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| 			 * The "on" field has undefined meaning if
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| 			 * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat
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| 			 * it as reserved, which must be set to zero.
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| 			 */
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| 			if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
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| 			    (perout->rsv[0] || perout->rsv[1] ||
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| 			     perout->rsv[2] || perout->rsv[3])) {
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| 				err = -EINVAL;
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| 				break;
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| 			}
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| 			if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
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| 				/* The duty cycle must be subunitary. */
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| 				if (perout->on.sec > perout->period.sec ||
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| 				    (perout->on.sec == perout->period.sec &&
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| 				     perout->on.nsec > perout->period.nsec)) {
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| 					err = -ERANGE;
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| 					break;
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| 				}
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| 			}
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| 			if (perout->flags & PTP_PEROUT_PHASE) {
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| 				/*
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| 				 * The phase should be specified modulo the
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| 				 * period, therefore anything equal or larger
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| 				 * than 1 period is invalid.
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| 				 */
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| 				if (perout->phase.sec > perout->period.sec ||
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| 				    (perout->phase.sec == perout->period.sec &&
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| 				     perout->phase.nsec >= perout->period.nsec)) {
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| 					err = -ERANGE;
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| 					break;
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| 				}
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| 			}
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| 		} else if (cmd == PTP_PEROUT_REQUEST) {
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| 			req.perout.flags &= PTP_PEROUT_V1_VALID_FLAGS;
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| 			req.perout.rsv[0] = 0;
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| 			req.perout.rsv[1] = 0;
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| 			req.perout.rsv[2] = 0;
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| 			req.perout.rsv[3] = 0;
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| 		}
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| 		if (req.perout.index >= ops->n_per_out) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		req.type = PTP_CLK_REQ_PEROUT;
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| 		enable = req.perout.period.sec || req.perout.period.nsec;
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| 		if (mutex_lock_interruptible(&ptp->pincfg_mux))
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| 			return -ERESTARTSYS;
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| 		err = ops->enable(ops, &req, enable);
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| 		mutex_unlock(&ptp->pincfg_mux);
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| 		break;
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| 
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| 	case PTP_ENABLE_PPS:
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| 	case PTP_ENABLE_PPS2:
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| 		memset(&req, 0, sizeof(req));
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| 
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| 		if (!capable(CAP_SYS_TIME))
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| 			return -EPERM;
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| 		req.type = PTP_CLK_REQ_PPS;
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| 		enable = arg ? 1 : 0;
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| 		if (mutex_lock_interruptible(&ptp->pincfg_mux))
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| 			return -ERESTARTSYS;
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| 		err = ops->enable(ops, &req, enable);
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| 		mutex_unlock(&ptp->pincfg_mux);
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| 		break;
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| 
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| 	case PTP_SYS_OFFSET_PRECISE:
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| 	case PTP_SYS_OFFSET_PRECISE2:
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| 		if (!ptp->info->getcrosststamp) {
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| 			err = -EOPNOTSUPP;
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| 			break;
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| 		}
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| 		err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
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| 		if (err)
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| 			break;
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| 
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| 		memset(&precise_offset, 0, sizeof(precise_offset));
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| 		ts = ktime_to_timespec64(xtstamp.device);
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| 		precise_offset.device.sec = ts.tv_sec;
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| 		precise_offset.device.nsec = ts.tv_nsec;
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| 		ts = ktime_to_timespec64(xtstamp.sys_realtime);
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| 		precise_offset.sys_realtime.sec = ts.tv_sec;
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| 		precise_offset.sys_realtime.nsec = ts.tv_nsec;
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| 		ts = ktime_to_timespec64(xtstamp.sys_monoraw);
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| 		precise_offset.sys_monoraw.sec = ts.tv_sec;
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| 		precise_offset.sys_monoraw.nsec = ts.tv_nsec;
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| 		if (copy_to_user((void __user *)arg, &precise_offset,
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| 				 sizeof(precise_offset)))
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| 			err = -EFAULT;
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| 		break;
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| 
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| 	case PTP_SYS_OFFSET_EXTENDED:
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| 	case PTP_SYS_OFFSET_EXTENDED2:
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| 		if (!ptp->info->gettimex64) {
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| 			err = -EOPNOTSUPP;
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| 			break;
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| 		}
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| 		extoff = memdup_user((void __user *)arg, sizeof(*extoff));
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| 		if (IS_ERR(extoff)) {
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| 			err = PTR_ERR(extoff);
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| 			extoff = NULL;
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| 			break;
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| 		}
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| 		if (extoff->n_samples > PTP_MAX_SAMPLES
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| 		    || extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		for (i = 0; i < extoff->n_samples; i++) {
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| 			err = ptp->info->gettimex64(ptp->info, &ts, &sts);
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| 			if (err)
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| 				goto out;
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| 			extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
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| 			extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
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| 			extoff->ts[i][1].sec = ts.tv_sec;
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| 			extoff->ts[i][1].nsec = ts.tv_nsec;
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| 			extoff->ts[i][2].sec = sts.post_ts.tv_sec;
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| 			extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
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| 		}
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| 		if (copy_to_user((void __user *)arg, extoff, sizeof(*extoff)))
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| 			err = -EFAULT;
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| 		break;
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| 
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| 	case PTP_SYS_OFFSET:
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| 	case PTP_SYS_OFFSET2:
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| 		sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
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| 		if (IS_ERR(sysoff)) {
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| 			err = PTR_ERR(sysoff);
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| 			sysoff = NULL;
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| 			break;
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| 		}
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| 		if (sysoff->n_samples > PTP_MAX_SAMPLES) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		pct = &sysoff->ts[0];
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| 		for (i = 0; i < sysoff->n_samples; i++) {
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| 			ktime_get_real_ts64(&ts);
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| 			pct->sec = ts.tv_sec;
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| 			pct->nsec = ts.tv_nsec;
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| 			pct++;
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| 			if (ops->gettimex64)
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| 				err = ops->gettimex64(ops, &ts, NULL);
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| 			else
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| 				err = ops->gettime64(ops, &ts);
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| 			if (err)
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| 				goto out;
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| 			pct->sec = ts.tv_sec;
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| 			pct->nsec = ts.tv_nsec;
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| 			pct++;
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| 		}
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| 		ktime_get_real_ts64(&ts);
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| 		pct->sec = ts.tv_sec;
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| 		pct->nsec = ts.tv_nsec;
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| 		if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
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| 			err = -EFAULT;
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| 		break;
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| 
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| 	case PTP_PIN_GETFUNC:
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| 	case PTP_PIN_GETFUNC2:
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| 		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
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| 			err = -EFAULT;
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| 			break;
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| 		}
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| 		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
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| 				|| pd.rsv[3] || pd.rsv[4])
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| 			&& cmd == PTP_PIN_GETFUNC2) {
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| 			err = -EINVAL;
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| 			break;
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| 		} else if (cmd == PTP_PIN_GETFUNC) {
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| 			pd.rsv[0] = 0;
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| 			pd.rsv[1] = 0;
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| 			pd.rsv[2] = 0;
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| 			pd.rsv[3] = 0;
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| 			pd.rsv[4] = 0;
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| 		}
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| 		pin_index = pd.index;
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| 		if (pin_index >= ops->n_pins) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		pin_index = array_index_nospec(pin_index, ops->n_pins);
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| 		if (mutex_lock_interruptible(&ptp->pincfg_mux))
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| 			return -ERESTARTSYS;
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| 		pd = ops->pin_config[pin_index];
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| 		mutex_unlock(&ptp->pincfg_mux);
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| 		if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
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| 			err = -EFAULT;
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| 		break;
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| 
 | |
| 	case PTP_PIN_SETFUNC:
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| 	case PTP_PIN_SETFUNC2:
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| 		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
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| 			err = -EFAULT;
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| 			break;
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| 		}
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| 		if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
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| 				|| pd.rsv[3] || pd.rsv[4])
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| 			&& cmd == PTP_PIN_SETFUNC2) {
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| 			err = -EINVAL;
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| 			break;
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| 		} else if (cmd == PTP_PIN_SETFUNC) {
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| 			pd.rsv[0] = 0;
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| 			pd.rsv[1] = 0;
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| 			pd.rsv[2] = 0;
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| 			pd.rsv[3] = 0;
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| 			pd.rsv[4] = 0;
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| 		}
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| 		pin_index = pd.index;
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| 		if (pin_index >= ops->n_pins) {
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| 			err = -EINVAL;
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| 			break;
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| 		}
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| 		pin_index = array_index_nospec(pin_index, ops->n_pins);
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| 		if (mutex_lock_interruptible(&ptp->pincfg_mux))
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| 			return -ERESTARTSYS;
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| 		err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
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| 		mutex_unlock(&ptp->pincfg_mux);
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| 		break;
 | |
| 
 | |
| 	default:
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| 		err = -ENOTTY;
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| 		break;
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| 	}
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| 
 | |
| out:
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| 	kfree(extoff);
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| 	kfree(sysoff);
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| 	return err;
 | |
| }
 | |
| 
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| __poll_t ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait)
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| {
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| 	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
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| 
 | |
| 	poll_wait(fp, &ptp->tsev_wq, wait);
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| 
 | |
| 	return queue_cnt(&ptp->tsevq) ? EPOLLIN : 0;
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| }
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| 
 | |
| #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
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| 
 | |
| ssize_t ptp_read(struct posix_clock *pc,
 | |
| 		 uint rdflags, char __user *buf, size_t cnt)
 | |
| {
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| 	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
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| 	struct timestamp_event_queue *queue = &ptp->tsevq;
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| 	struct ptp_extts_event *event;
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| 	unsigned long flags;
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| 	size_t qcnt, i;
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| 	int result;
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| 
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| 	if (cnt % sizeof(struct ptp_extts_event) != 0)
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| 		return -EINVAL;
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| 
 | |
| 	if (cnt > EXTTS_BUFSIZE)
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| 		cnt = EXTTS_BUFSIZE;
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| 
 | |
| 	cnt = cnt / sizeof(struct ptp_extts_event);
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| 
 | |
| 	if (mutex_lock_interruptible(&ptp->tsevq_mux))
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| 		return -ERESTARTSYS;
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| 
 | |
| 	if (wait_event_interruptible(ptp->tsev_wq,
 | |
| 				     ptp->defunct || queue_cnt(queue))) {
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| 		mutex_unlock(&ptp->tsevq_mux);
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| 		return -ERESTARTSYS;
 | |
| 	}
 | |
| 
 | |
| 	if (ptp->defunct) {
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| 		mutex_unlock(&ptp->tsevq_mux);
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| 		return -ENODEV;
 | |
| 	}
 | |
| 
 | |
| 	event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
 | |
| 	if (!event) {
 | |
| 		mutex_unlock(&ptp->tsevq_mux);
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| 		return -ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	spin_lock_irqsave(&queue->lock, flags);
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| 
 | |
| 	qcnt = queue_cnt(queue);
 | |
| 
 | |
| 	if (cnt > qcnt)
 | |
| 		cnt = qcnt;
 | |
| 
 | |
| 	for (i = 0; i < cnt; i++) {
 | |
| 		event[i] = queue->buf[queue->head];
 | |
| 		/* Paired with READ_ONCE() in queue_cnt() */
 | |
| 		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
 | |
| 	}
 | |
| 
 | |
| 	spin_unlock_irqrestore(&queue->lock, flags);
 | |
| 
 | |
| 	cnt = cnt * sizeof(struct ptp_extts_event);
 | |
| 
 | |
| 	mutex_unlock(&ptp->tsevq_mux);
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| 
 | |
| 	result = cnt;
 | |
| 	if (copy_to_user(buf, event, cnt))
 | |
| 		result = -EFAULT;
 | |
| 
 | |
| 	kfree(event);
 | |
| 	return result;
 | |
| }
 |