[mirror_ubuntu-artful-kernel.git] / drivers / uwb / pal.c

/*
 * UWB PAL support.
 *
 * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */
#include <linux/kernel.h>
#include <linux/debugfs.h>
#include <linux/uwb.h>
#include <linux/export.h>

#include "uwb-internal.h"

/**
 * uwb_pal_init - initialize a UWB PAL
 * @pal: the PAL to initialize
 */
void uwb_pal_init(struct uwb_pal *pal)
{
	INIT_LIST_HEAD(&pal->node);
}
EXPORT_SYMBOL_GPL(uwb_pal_init);

/**
 * uwb_pal_register - register a UWB PAL
 * @pal: the PAL
 *
 * The PAL must be initialized with uwb_pal_init().
 */
int uwb_pal_register(struct uwb_pal *pal)
{
	struct uwb_rc *rc = pal->rc;
	int ret;

	if (pal->device) {
		/* create a link to the uwb_rc in the PAL device's directory. */
		ret = sysfs_create_link(&pal->device->kobj,
					&rc->uwb_dev.dev.kobj, "uwb_rc");
		if (ret < 0)
			return ret;
		/* create a link to the PAL in the UWB device's directory. */
		ret = sysfs_create_link(&rc->uwb_dev.dev.kobj,
					&pal->device->kobj, pal->name);
		if (ret < 0) {
			sysfs_remove_link(&pal->device->kobj, "uwb_rc");
			return ret;
		}
	}

	pal->debugfs_dir = uwb_dbg_create_pal_dir(pal);

	mutex_lock(&rc->uwb_dev.mutex);
	list_add(&pal->node, &rc->pals);
	mutex_unlock(&rc->uwb_dev.mutex);

	return 0;
}
EXPORT_SYMBOL_GPL(uwb_pal_register);

static int find_rc(struct device *dev, const void *data)
{
	const struct uwb_rc *target_rc = data;
	struct uwb_rc *rc = dev_get_drvdata(dev);

	if (rc == NULL) {
		WARN_ON(1);
		return 0;
	}
	if (rc == target_rc) {
		if (rc->ready == 0)
			return 0;
		else
			return 1;
	}
	return 0;
}

/**
 * Given a radio controller descriptor see if it is registered.
 *
 * @returns false if the rc does not exist or is quiescing; true otherwise.
 */
static bool uwb_rc_class_device_exists(struct uwb_rc *target_rc)
{
	struct device *dev;

	dev = class_find_device(&uwb_rc_class, NULL, target_rc,	find_rc);

	put_device(dev);

	return (dev != NULL);
}

/**
 * uwb_pal_unregister - unregister a UWB PAL
 * @pal: the PAL
 */
void uwb_pal_unregister(struct uwb_pal *pal)
{
	struct uwb_rc *rc = pal->rc;

	uwb_radio_stop(pal);

	mutex_lock(&rc->uwb_dev.mutex);
	list_del(&pal->node);
	mutex_unlock(&rc->uwb_dev.mutex);

	debugfs_remove(pal->debugfs_dir);

	if (pal->device) {
		/* remove link to the PAL in the UWB device's directory. */
		if (uwb_rc_class_device_exists(rc))
			sysfs_remove_link(&rc->uwb_dev.dev.kobj, pal->name);

		/* remove link to uwb_rc in the PAL device's directory. */
		sysfs_remove_link(&pal->device->kobj, "uwb_rc");
	}
}
EXPORT_SYMBOL_GPL(uwb_pal_unregister);

/**
 * uwb_rc_pal_init - initialize the PAL related parts of a radio controller
 * @rc: the radio controller
 */
void uwb_rc_pal_init(struct uwb_rc *rc)
{
	INIT_LIST_HEAD(&rc->pals);
}
Commit	Line	Data
183b9b59 IPG	1	/*
	2	* UWB PAL support.
	3	*
	4	* Copyright (C) 2008 Cambridge Silicon Radio Ltd.
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License version
	8	* 2 as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	17	*/
	18	#include <linux/kernel.h>
dcc7461e	19	#include <linux/debugfs.h>
183b9b59	20	#include <linux/uwb.h>
475c0a6b	21	#include <linux/export.h>
183b9b59 IPG	22
	23	#include "uwb-internal.h"
	24
	25	/**
	26	* uwb_pal_init - initialize a UWB PAL
	27	* @pal: the PAL to initialize
	28	*/
	29	void uwb_pal_init(struct uwb_pal *pal)
	30	{
	31	INIT_LIST_HEAD(&pal->node);
	32	}
	33	EXPORT_SYMBOL_GPL(uwb_pal_init);
	34
	35	/**
	36	* uwb_pal_register - register a UWB PAL
183b9b59 IPG	37	* @pal: the PAL
	38	*
	39	* The PAL must be initialized with uwb_pal_init().
	40	*/
6fae35f9	41	int uwb_pal_register(struct uwb_pal *pal)
183b9b59	42	{
6fae35f9	43	struct uwb_rc *rc = pal->rc;
b60066c1 DV	44	int ret;
	45
	46	if (pal->device) {
a8995751	47	/* create a link to the uwb_rc in the PAL device's directory. */
b60066c1 DV	48	ret = sysfs_create_link(&pal->device->kobj,
	49	&rc->uwb_dev.dev.kobj, "uwb_rc");
	50	if (ret < 0)
	51	return ret;
a8995751	52	/* create a link to the PAL in the UWB device's directory. */
b60066c1 DV	53	ret = sysfs_create_link(&rc->uwb_dev.dev.kobj,
	54	&pal->device->kobj, pal->name);
	55	if (ret < 0) {
	56	sysfs_remove_link(&pal->device->kobj, "uwb_rc");
	57	return ret;
	58	}
	59	}
	60
dcc7461e DV	61	pal->debugfs_dir = uwb_dbg_create_pal_dir(pal);
dcc7461e DV	62
6fae35f9	63	mutex_lock(&rc->uwb_dev.mutex);
183b9b59	64	list_add(&pal->node, &rc->pals);
6fae35f9	65	mutex_unlock(&rc->uwb_dev.mutex);
183b9b59 IPG	66
	67	return 0;
	68	}
	69	EXPORT_SYMBOL_GPL(uwb_pal_register);
	70
fbbde074 TP	71	static int find_rc(struct device dev, const void data)
	72	{
	73	const struct uwb_rc *target_rc = data;
	74	struct uwb_rc *rc = dev_get_drvdata(dev);
	75
	76	if (rc == NULL) {
	77	WARN_ON(1);
	78	return 0;
	79	}
	80	if (rc == target_rc) {
	81	if (rc->ready == 0)
	82	return 0;
	83	else
	84	return 1;
	85	}
	86	return 0;
	87	}
	88
	89	/**
	90	* Given a radio controller descriptor see if it is registered.
	91	*
	92	* @returns false if the rc does not exist or is quiescing; true otherwise.
	93	*/
	94	static bool uwb_rc_class_device_exists(struct uwb_rc *target_rc)
	95	{
	96	struct device *dev;
	97
	98	dev = class_find_device(&uwb_rc_class, NULL, target_rc, find_rc);
	99
d6124b40 JH	100	put_device(dev);
d6124b40 JH	101
fbbde074 TP	102	return (dev != NULL);
	103	}
	104
183b9b59	105	/**
fbbde074	106	* uwb_pal_unregister - unregister a UWB PAL
183b9b59 IPG	107	* @pal: the PAL
183b9b59 IPG	108	*/
6fae35f9	109	void uwb_pal_unregister(struct uwb_pal *pal)
183b9b59	110	{
6fae35f9 DV	111	struct uwb_rc *rc = pal->rc;
	112
	113	uwb_radio_stop(pal);
	114
	115	mutex_lock(&rc->uwb_dev.mutex);
183b9b59	116	list_del(&pal->node);
6fae35f9	117	mutex_unlock(&rc->uwb_dev.mutex);
b60066c1	118
dcc7461e DV	119	debugfs_remove(pal->debugfs_dir);
dcc7461e DV	120
b60066c1	121	if (pal->device) {
fbbde074 TP	122	/* remove link to the PAL in the UWB device's directory. */
	123	if (uwb_rc_class_device_exists(rc))
	124	sysfs_remove_link(&rc->uwb_dev.dev.kobj, pal->name);
	125
	126	/* remove link to uwb_rc in the PAL device's directory. */
b60066c1 DV	127	sysfs_remove_link(&pal->device->kobj, "uwb_rc");
b60066c1 DV	128	}
183b9b59 IPG	129	}
	130	EXPORT_SYMBOL_GPL(uwb_pal_unregister);
	131
	132	/**
	133	* uwb_rc_pal_init - initialize the PAL related parts of a radio controller
	134	* @rc: the radio controller
	135	*/
	136	void uwb_rc_pal_init(struct uwb_rc *rc)
	137	{
183b9b59 IPG	138	INIT_LIST_HEAD(&rc->pals);
183b9b59 IPG	139	}