[linux-2.6-block.git] / drivers / staging / iio / trigger / iio-trig-periodic-rtc.c

/* The industrial I/O periodic RTC trigger driver
 *
 * Copyright (c) 2008 Jonathan Cameron
 *
 * 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 is a heavily rewritten version of the periodic timer system in
 * earlier version of industrialio.  It supplies the same functionality
 * but via a trigger rather than a specific periodic timer system.
 */

#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/rtc.h>
#include "../iio.h"
#include "../trigger.h"

LIST_HEAD(iio_prtc_trigger_list);
DEFINE_MUTEX(iio_prtc_trigger_list_lock);

struct iio_prtc_trigger_info {
	struct rtc_device *rtc;
	int frequency;
	char *name;
	struct rtc_task task;
};

static int iio_trig_periodic_rtc_set_state(struct iio_trigger *trig, bool state)
{
	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	if (trig_info->frequency == 0)
		return -EINVAL;
	printk(KERN_INFO "trigger frequency is %d\n", trig_info->frequency);
	return rtc_irq_set_state(trig_info->rtc, &trig_info->task, state);
}

static ssize_t iio_trig_periodic_read_freq(struct device *dev,
					   struct device_attribute *attr,
					   char *buf)
{
	struct iio_trigger *trig = dev_get_drvdata(dev);
	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	return sprintf(buf, "%u\n", trig_info->frequency);
}

static ssize_t iio_trig_periodic_write_freq(struct device *dev,
					    struct device_attribute *attr,
					    const char *buf,
					    size_t len)
{
	struct iio_trigger *trig = dev_get_drvdata(dev);
	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	unsigned long val;
	int ret;

	ret = strict_strtoul(buf, 10, &val);
	if (ret)
		goto error_ret;

	ret = rtc_irq_set_freq(trig_info->rtc, &trig_info->task, val);
	if (ret)
		goto error_ret;

	trig_info->frequency = val;

	return len;

error_ret:
	return ret;
}

static ssize_t iio_trig_periodic_read_name(struct device *dev,
					   struct device_attribute *attr,
					   char *buf)
{
	struct iio_trigger *trig = dev_get_drvdata(dev);
	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	return sprintf(buf, "%s\n", trig_info->name);
}

static DEVICE_ATTR(name, S_IRUGO,
	    iio_trig_periodic_read_name,
	    NULL);
static DEVICE_ATTR(frequency, S_IRUGO | S_IWUSR,
	    iio_trig_periodic_read_freq,
	    iio_trig_periodic_write_freq);

static struct attribute *iio_trig_prtc_attrs[] = {
	&dev_attr_frequency.attr,
	&dev_attr_name.attr,
	NULL,
};
static const struct attribute_group iio_trig_prtc_attr_group = {
	.attrs = iio_trig_prtc_attrs,
};

static void iio_prtc_trigger_poll(void *private_data)
{
	iio_trigger_poll(private_data);
}

static int iio_trig_periodic_rtc_probe(struct platform_device *dev)
{
	char **pdata = dev->dev.platform_data;
	struct iio_prtc_trigger_info *trig_info;
	struct iio_trigger *trig, *trig2;

	int i, ret;

	for (i = 0;; i++) {
		if (pdata[i] == NULL)
			break;
		trig = iio_allocate_trigger();
		if (!trig) {
			ret = -ENOMEM;
			goto error_free_completed_registrations;
		}
		list_add(&trig->alloc_list, &iio_prtc_trigger_list);

		trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
		if (!trig_info) {
			ret = -ENOMEM;
			goto error_put_trigger_and_remove_from_list;
		}
		trig->private_data = trig_info;
		trig->owner = THIS_MODULE;
		trig->set_trigger_state = &iio_trig_periodic_rtc_set_state;
		trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL);
		if (trig->name == NULL) {
			ret = -ENOMEM;
			goto error_free_trig_info;
		}
		snprintf((char *)trig->name,
			 IIO_TRIGGER_NAME_LENGTH,
			 "periodic%s",
			 pdata[i]);
		trig_info->name = (char *)trig->name;
		/* RTC access */
		trig_info->rtc
			= rtc_class_open(pdata[i]);
		if (trig_info->rtc == NULL) {
			ret = -EINVAL;
			goto error_free_name;
		}
		trig_info->task.func = iio_prtc_trigger_poll;
		trig_info->task.private_data = trig;
		ret = rtc_irq_register(trig_info->rtc, &trig_info->task);
		if (ret)
			goto error_close_rtc;
		trig->control_attrs = &iio_trig_prtc_attr_group;
		ret = iio_trigger_register(trig);
		if (ret)
			goto error_unregister_rtc_irq;
	}
	return 0;
error_unregister_rtc_irq:
	rtc_irq_unregister(trig_info->rtc, &trig_info->task);
error_close_rtc:
	rtc_class_close(trig_info->rtc);
error_free_name:
	kfree(trig->name);
error_free_trig_info:
	kfree(trig_info);
error_put_trigger_and_remove_from_list:
	list_del(&trig->alloc_list);
	iio_put_trigger(trig);
error_free_completed_registrations:
	list_for_each_entry_safe(trig,
				 trig2,
				 &iio_prtc_trigger_list,
				 alloc_list) {
		trig_info = trig->private_data;
		rtc_irq_unregister(trig_info->rtc, &trig_info->task);
		rtc_class_close(trig_info->rtc);
		kfree(trig->name);
		kfree(trig_info);
		iio_trigger_unregister(trig);
	}
	return ret;
}

static int iio_trig_periodic_rtc_remove(struct platform_device *dev)
{
	struct iio_trigger *trig, *trig2;
	struct iio_prtc_trigger_info *trig_info;
	mutex_lock(&iio_prtc_trigger_list_lock);
	list_for_each_entry_safe(trig,
				 trig2,
				 &iio_prtc_trigger_list,
				 alloc_list) {
		trig_info = trig->private_data;
		rtc_irq_unregister(trig_info->rtc, &trig_info->task);
		rtc_class_close(trig_info->rtc);
		kfree(trig->name);
		kfree(trig_info);
		iio_trigger_unregister(trig);
	}
	mutex_unlock(&iio_prtc_trigger_list_lock);
	return 0;
}

static struct platform_driver iio_trig_periodic_rtc_driver = {
	.probe = iio_trig_periodic_rtc_probe,
	.remove = iio_trig_periodic_rtc_remove,
	.driver = {
		.name = "iio_prtc_trigger",
		.owner = THIS_MODULE,
	},
};

static int __init iio_trig_periodic_rtc_init(void)
{
	return platform_driver_register(&iio_trig_periodic_rtc_driver);
}

static void __exit iio_trig_periodic_rtc_exit(void)
{
	return platform_driver_unregister(&iio_trig_periodic_rtc_driver);
}

module_init(iio_trig_periodic_rtc_init);
module_exit(iio_trig_periodic_rtc_exit);
MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
MODULE_DESCRIPTION("Periodic realtime clock  trigger for the iio subsystem");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
7f3a1fb9 JC	1	/* The industrial I/O periodic RTC trigger driver
	2	*
	3	* Copyright (c) 2008 Jonathan Cameron
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License version 2 as published by
	7	* the Free Software Foundation.
	8	*
	9	* This is a heavily rewritten version of the periodic timer system in
	10	* earlier version of industrialio. It supplies the same functionality
	11	* but via a trigger rather than a specific periodic timer system.
	12	*/
	13
	14	#include <linux/platform_device.h>
	15	#include <linux/kernel.h>
	16	#include <linux/module.h>
5a0e3ad6	17	#include <linux/slab.h>
7f3a1fb9 JC	18	#include <linux/rtc.h>
	19	#include "../iio.h"
	20	#include "../trigger.h"
	21
	22	LIST_HEAD(iio_prtc_trigger_list);
	23	DEFINE_MUTEX(iio_prtc_trigger_list_lock);
	24
	25	struct iio_prtc_trigger_info {
	26	struct rtc_device *rtc;
	27	int frequency;
	28	char *name;
	29	struct rtc_task task;
	30	};
	31
	32	static int iio_trig_periodic_rtc_set_state(struct iio_trigger *trig, bool state)
	33	{
	34	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	35	if (trig_info->frequency == 0)
	36	return -EINVAL;
	37	printk(KERN_INFO "trigger frequency is %d\n", trig_info->frequency);
	38	return rtc_irq_set_state(trig_info->rtc, &trig_info->task, state);
	39	}
	40
	41	static ssize_t iio_trig_periodic_read_freq(struct device *dev,
	42	struct device_attribute *attr,
	43	char *buf)
	44	{
	45	struct iio_trigger *trig = dev_get_drvdata(dev);
	46	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	47	return sprintf(buf, "%u\n", trig_info->frequency);
	48	}
	49
	50	static ssize_t iio_trig_periodic_write_freq(struct device *dev,
	51	struct device_attribute *attr,
	52	const char *buf,
	53	size_t len)
	54	{
	55	struct iio_trigger *trig = dev_get_drvdata(dev);
	56	struct iio_prtc_trigger_info *trig_info = trig->private_data;
	57	unsigned long val;
	58	int ret;
	59
	60	ret = strict_strtoul(buf, 10, &val);
	61	if (ret)
	62	goto error_ret;
	63
	64	ret = rtc_irq_set_freq(trig_info->rtc, &trig_info->task, val);
	65	if (ret)
	66	goto error_ret;
	67
	68	trig_info->frequency = val;
	69
	70	return len;
	71
	72	error_ret:
	73	return ret;
	74	}
	75
	76	static ssize_t iio_trig_periodic_read_name(struct device *dev,
	77	struct device_attribute *attr,
	78	char *buf)
	79	{
	80	struct iio_trigger *trig = dev_get_drvdata(dev);
	81	struct iio_prtc_trigger_info *trig_info = trig->private_data;
82	return sprintf(buf, "%s\n", trig_info->name);
83	}
84
2fdec576	85	static DEVICE_ATTR(name, S_IRUGO,
7f3a1fb9 JC	86	iio_trig_periodic_read_name,
7f3a1fb9 JC	87	NULL);
2fdec576	88	static DEVICE_ATTR(frequency, S_IRUGO \| S_IWUSR,
7f3a1fb9 JC	89	iio_trig_periodic_read_freq,
	90	iio_trig_periodic_write_freq);
	91
	92	static struct attribute *iio_trig_prtc_attrs[] = {
	93	&dev_attr_frequency.attr,
	94	&dev_attr_name.attr,
	95	NULL,
	96	};
	97	static const struct attribute_group iio_trig_prtc_attr_group = {
	98	.attrs = iio_trig_prtc_attrs,
	99	};
	100
	101	static void iio_prtc_trigger_poll(void *private_data)
	102	{
	103	iio_trigger_poll(private_data);
	104	}
	105
	106	static int iio_trig_periodic_rtc_probe(struct platform_device *dev)
	107	{
	108	char **pdata = dev->dev.platform_data;
	109	struct iio_prtc_trigger_info *trig_info;
	110	struct iio_trigger trig, trig2;
	111
	112	int i, ret;
	113
	114	for (i = 0;; i++) {
	115	if (pdata[i] == NULL)
	116	break;
	117	trig = iio_allocate_trigger();
	118	if (!trig) {
	119	ret = -ENOMEM;
	120	goto error_free_completed_registrations;
	121	}
	122	list_add(&trig->alloc_list, &iio_prtc_trigger_list);
	123
	124	trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
	125	if (!trig_info) {
	126	ret = -ENOMEM;
	127	goto error_put_trigger_and_remove_from_list;
	128	}
	129	trig->private_data = trig_info;
	130	trig->owner = THIS_MODULE;
	131	trig->set_trigger_state = &iio_trig_periodic_rtc_set_state;
	132	trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL);
	133	if (trig->name == NULL) {
	134	ret = -ENOMEM;
	135	goto error_free_trig_info;
	136	}
	137	snprintf((char *)trig->name,
	138	IIO_TRIGGER_NAME_LENGTH,
	139	"periodic%s",
	140	pdata[i]);
	141	trig_info->name = (char *)trig->name;
	142	/* RTC access */
	143	trig_info->rtc
	144	= rtc_class_open(pdata[i]);
	145	if (trig_info->rtc == NULL) {
	146	ret = -EINVAL;
	147	goto error_free_name;
	148	}
	149	trig_info->task.func = iio_prtc_trigger_poll;
	150	trig_info->task.private_data = trig;
	151	ret = rtc_irq_register(trig_info->rtc, &trig_info->task);
	152	if (ret)
153	goto error_close_rtc;
154	trig->control_attrs = &iio_trig_prtc_attr_group;
155	ret = iio_trigger_register(trig);
156	if (ret)
157	goto error_unregister_rtc_irq;
158	}
159	return 0;
160	error_unregister_rtc_irq:
161	rtc_irq_unregister(trig_info->rtc, &trig_info->task);
162	error_close_rtc:
163	rtc_class_close(trig_info->rtc);
164	error_free_name:
165	kfree(trig->name);
166	error_free_trig_info:
167	kfree(trig_info);
168	error_put_trigger_and_remove_from_list:
169	list_del(&trig->alloc_list);
170	iio_put_trigger(trig);
171	error_free_completed_registrations:
172	list_for_each_entry_safe(trig,
173	trig2,
174	&iio_prtc_trigger_list,
175	alloc_list) {
176	trig_info = trig->private_data;
177	rtc_irq_unregister(trig_info->rtc, &trig_info->task);
178	rtc_class_close(trig_info->rtc);
179	kfree(trig->name);
180	kfree(trig_info);
181	iio_trigger_unregister(trig);
182	}
183	return ret;
184	}
185
186	static int iio_trig_periodic_rtc_remove(struct platform_device *dev)
187	{
188	struct iio_trigger trig, trig2;
189	struct iio_prtc_trigger_info *trig_info;
190	mutex_lock(&iio_prtc_trigger_list_lock);
191	list_for_each_entry_safe(trig,
192	trig2,
193	&iio_prtc_trigger_list,
194	alloc_list) {
195	trig_info = trig->private_data;
196	rtc_irq_unregister(trig_info->rtc, &trig_info->task);
197	rtc_class_close(trig_info->rtc);
198	kfree(trig->name);
199	kfree(trig_info);
200	iio_trigger_unregister(trig);
201	}
202	mutex_unlock(&iio_prtc_trigger_list_lock);
203	return 0;
204	}
205
206	static struct platform_driver iio_trig_periodic_rtc_driver = {
207	.probe = iio_trig_periodic_rtc_probe,
208	.remove = iio_trig_periodic_rtc_remove,
209	.driver = {
210	.name = "iio_prtc_trigger",
211	.owner = THIS_MODULE,
212	},
213	};
214
215	static int __init iio_trig_periodic_rtc_init(void)
216	{
217	return platform_driver_register(&iio_trig_periodic_rtc_driver);
218	}
219
220	static void __exit iio_trig_periodic_rtc_exit(void)
221	{
222	return platform_driver_unregister(&iio_trig_periodic_rtc_driver);
223	}
224
225	module_init(iio_trig_periodic_rtc_init);
226	module_exit(iio_trig_periodic_rtc_exit);
227	MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
228	MODULE_DESCRIPTION("Periodic realtime clock trigger for the iio subsystem");
229	MODULE_LICENSE("GPL v2");