/*
   * PTP 1588 clock support - sysfs interface.
   *
   * Copyright (C) 2010 OMICRON electronics GmbH
   *
   *  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 <linux/capability.h>

  #include <linux/slab.h>

  
  #include "ptp_private.h"
  
  static ssize_t clock_name_show(struct device *dev,
  			       struct device_attribute *attr, char *page)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	return snprintf(page, PAGE_SIZE-1, "%s
  ", ptp->info->name);
  }

  static DEVICE_ATTR_RO(clock_name);

  #define PTP_SHOW_INT(name, var)						\
  static ssize_t var##_show(struct device *dev,				\

  			   struct device_attribute *attr, char *page)	\
  {									\
  	struct ptp_clock *ptp = dev_get_drvdata(dev);			\

  	return snprintf(page, PAGE_SIZE-1, "%d
  ", ptp->info->var);	\
  }									\
  static DEVICE_ATTR(name, 0444, var##_show, NULL);

  PTP_SHOW_INT(max_adjustment, max_adj);
  PTP_SHOW_INT(n_alarms, n_alarm);
  PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
  PTP_SHOW_INT(n_periodic_outputs, n_per_out);

  PTP_SHOW_INT(n_programmable_pins, n_pins);

  PTP_SHOW_INT(pps_available, pps);

  static ssize_t extts_enable_store(struct device *dev,
  				  struct device_attribute *attr,
  				  const char *buf, size_t count)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	struct ptp_clock_info *ops = ptp->info;
  	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
  	int cnt, enable;
  	int err = -EINVAL;
  
  	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
  	if (cnt != 2)
  		goto out;
  	if (req.extts.index >= ops->n_ext_ts)
  		goto out;
  
  	err = ops->enable(ops, &req, enable ? 1 : 0);
  	if (err)
  		goto out;
  
  	return count;
  out:
  	return err;
  }

  static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);

  
  static ssize_t extts_fifo_show(struct device *dev,
  			       struct device_attribute *attr, char *page)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	struct timestamp_event_queue *queue = &ptp->tsevq;
  	struct ptp_extts_event event;
  	unsigned long flags;
  	size_t qcnt;
  	int cnt = 0;
  
  	memset(&event, 0, sizeof(event));
  
  	if (mutex_lock_interruptible(&ptp->tsevq_mux))
  		return -ERESTARTSYS;
  
  	spin_lock_irqsave(&queue->lock, flags);
  	qcnt = queue_cnt(queue);
  	if (qcnt) {
  		event = queue->buf[queue->head];
  		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
  	}
  	spin_unlock_irqrestore(&queue->lock, flags);
  
  	if (!qcnt)
  		goto out;
  
  	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u
  ",
  		       event.index, event.t.sec, event.t.nsec);
  out:
  	mutex_unlock(&ptp->tsevq_mux);
  	return cnt;
  }

  static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);

  
  static ssize_t period_store(struct device *dev,
  			    struct device_attribute *attr,
  			    const char *buf, size_t count)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	struct ptp_clock_info *ops = ptp->info;
  	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
  	int cnt, enable, err = -EINVAL;
  
  	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
  		     &req.perout.start.sec, &req.perout.start.nsec,
  		     &req.perout.period.sec, &req.perout.period.nsec);
  	if (cnt != 5)
  		goto out;
  	if (req.perout.index >= ops->n_per_out)
  		goto out;
  
  	enable = req.perout.period.sec || req.perout.period.nsec;
  	err = ops->enable(ops, &req, enable);
  	if (err)
  		goto out;
  
  	return count;
  out:
  	return err;
  }

  static DEVICE_ATTR(period, 0220, NULL, period_store);

  
  static ssize_t pps_enable_store(struct device *dev,
  				struct device_attribute *attr,
  				const char *buf, size_t count)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	struct ptp_clock_info *ops = ptp->info;
  	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
  	int cnt, enable;
  	int err = -EINVAL;
  
  	if (!capable(CAP_SYS_TIME))
  		return -EPERM;
  
  	cnt = sscanf(buf, "%d", &enable);
  	if (cnt != 1)
  		goto out;
  
  	err = ops->enable(ops, &req, enable ? 1 : 0);
  	if (err)
  		goto out;
  
  	return count;
  out:
  	return err;
  }

  static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
  
  static struct attribute *ptp_attrs[] = {
  	&dev_attr_clock_name.attr,
  
  	&dev_attr_max_adjustment.attr,
  	&dev_attr_n_alarms.attr,
  	&dev_attr_n_external_timestamps.attr,
  	&dev_attr_n_periodic_outputs.attr,
  	&dev_attr_n_programmable_pins.attr,
  	&dev_attr_pps_available.attr,
  
  	&dev_attr_extts_enable.attr,
  	&dev_attr_fifo.attr,
  	&dev_attr_period.attr,
  	&dev_attr_pps_enable.attr,
  	NULL
  };
  
  static umode_t ptp_is_attribute_visible(struct kobject *kobj,
  					struct attribute *attr, int n)
  {
  	struct device *dev = kobj_to_dev(kobj);
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	struct ptp_clock_info *info = ptp->info;
  	umode_t mode = attr->mode;
  
  	if (attr == &dev_attr_extts_enable.attr ||
  	    attr == &dev_attr_fifo.attr) {
  		if (!info->n_ext_ts)
  			mode = 0;
  	} else if (attr == &dev_attr_period.attr) {
  		if (!info->n_per_out)
  			mode = 0;
  	} else if (attr == &dev_attr_pps_enable.attr) {
  		if (!info->pps)
  			mode = 0;
  	}
  
  	return mode;
  }
  
  static const struct attribute_group ptp_group = {
  	.is_visible	= ptp_is_attribute_visible,
  	.attrs		= ptp_attrs,
  };
  
  const struct attribute_group *ptp_groups[] = {
  	&ptp_group,
  	NULL
  };

  static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
  {
  	int i;
  	for (i = 0; i < ptp->info->n_pins; i++) {
  		if (!strcmp(ptp->info->pin_config[i].name, name))
  			return i;
  	}
  	return -1;
  }
  
  static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
  			    char *page)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	unsigned int func, chan;
  	int index;
  
  	index = ptp_pin_name2index(ptp, attr->attr.name);
  	if (index < 0)
  		return -EINVAL;
  
  	if (mutex_lock_interruptible(&ptp->pincfg_mux))
  		return -ERESTARTSYS;
  
  	func = ptp->info->pin_config[index].func;
  	chan = ptp->info->pin_config[index].chan;
  
  	mutex_unlock(&ptp->pincfg_mux);
  
  	return snprintf(page, PAGE_SIZE, "%u %u
  ", func, chan);
  }
  
  static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
  			     const char *buf, size_t count)
  {
  	struct ptp_clock *ptp = dev_get_drvdata(dev);
  	unsigned int func, chan;
  	int cnt, err, index;
  
  	cnt = sscanf(buf, "%u %u", &func, &chan);
  	if (cnt != 2)
  		return -EINVAL;
  
  	index = ptp_pin_name2index(ptp, attr->attr.name);
  	if (index < 0)
  		return -EINVAL;
  
  	if (mutex_lock_interruptible(&ptp->pincfg_mux))
  		return -ERESTARTSYS;
  	err = ptp_set_pinfunc(ptp, index, func, chan);
  	mutex_unlock(&ptp->pincfg_mux);
  	if (err)
  		return err;
  
  	return count;
  }

  int ptp_populate_pin_groups(struct ptp_clock *ptp)

  {

  	struct ptp_clock_info *info = ptp->info;
  	int err = -ENOMEM, i, n_pins = info->n_pins;

  	if (!n_pins)
  		return 0;

  	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),

  				    GFP_KERNEL);
  	if (!ptp->pin_dev_attr)
  		goto no_dev_attr;

  	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);

  	if (!ptp->pin_attr)
  		goto no_pin_attr;
  
  	for (i = 0; i < n_pins; i++) {
  		struct device_attribute *da = &ptp->pin_dev_attr[i];
  		sysfs_attr_init(&da->attr);
  		da->attr.name = info->pin_config[i].name;
  		da->attr.mode = 0644;
  		da->show = ptp_pin_show;
  		da->store = ptp_pin_store;
  		ptp->pin_attr[i] = &da->attr;
  	}
  
  	ptp->pin_attr_group.name = "pins";
  	ptp->pin_attr_group.attrs = ptp->pin_attr;

  	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;

  	return 0;

  no_pin_attr:
  	kfree(ptp->pin_dev_attr);
  no_dev_attr:
  	return err;
  }

  void ptp_cleanup_pin_groups(struct ptp_clock *ptp)

  {

  	kfree(ptp->pin_attr);
  	kfree(ptp->pin_dev_attr);

  }