[linux.git] / drivers / macintosh / windfarm_core.c

/*
 * Windfarm PowerMac thermal control. Core
 *
 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
 *                    <[email protected]>
 *
 * Released under the term of the GNU GPL v2.
 *
 * This core code tracks the list of sensors & controls, register
 * clients, and holds the kernel thread used for control.
 *
 * TODO:
 *
 * Add some information about sensor/control type and data format to
 * sensors/controls, and have the sysfs attribute stuff be moved
 * generically here instead of hard coded in the platform specific
 * driver as it us currently
 *
 * This however requires solving some annoying lifetime issues with
 * sysfs which doesn't seem to have lifetime rules for struct attribute,
 * I may have to create full features kobjects for every sensor/control
 * instead which is a bit of an overkill imho
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/smp_lock.h>
#include <linux/kthread.h>
#include <linux/jiffies.h>
#include <linux/reboot.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>

#include <asm/prom.h>

#include "windfarm.h"

#define VERSION "0.2"

#undef DEBUG

#ifdef DEBUG
#define DBG(args...)	printk(args)
#else
#define DBG(args...)	do { } while(0)
#endif

static LIST_HEAD(wf_controls);
static LIST_HEAD(wf_sensors);
static DEFINE_MUTEX(wf_lock);
static BLOCKING_NOTIFIER_HEAD(wf_client_list);
static int wf_client_count;
static unsigned int wf_overtemp;
static unsigned int wf_overtemp_counter;
struct task_struct *wf_thread;

static struct platform_device wf_platform_device = {
	.name	= "windfarm",
};

/*
 * Utilities & tick thread
 */

static inline void wf_notify(int event, void *param)
{
	blocking_notifier_call_chain(&wf_client_list, event, param);
}

int wf_critical_overtemp(void)
{
	static char * critical_overtemp_path = "/sbin/critical_overtemp";
	char *argv[] = { critical_overtemp_path, NULL };
	static char *envp[] = { "HOME=/",
				"TERM=linux",
				"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
				NULL };

	return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
}
EXPORT_SYMBOL_GPL(wf_critical_overtemp);

static int wf_thread_func(void *data)
{
	unsigned long next, delay;

	next = jiffies;

	DBG("wf: thread started\n");

	while(!kthread_should_stop()) {
		try_to_freeze();

		if (time_after_eq(jiffies, next)) {
			wf_notify(WF_EVENT_TICK, NULL);
			if (wf_overtemp) {
				wf_overtemp_counter++;
				/* 10 seconds overtemp, notify userland */
				if (wf_overtemp_counter > 10)
					wf_critical_overtemp();
				/* 30 seconds, shutdown */
				if (wf_overtemp_counter > 30) {
					printk(KERN_ERR "windfarm: Overtemp "
					       "for more than 30"
					       " seconds, shutting down\n");
					machine_power_off();
				}
			}
			next += HZ;
		}

		delay = next - jiffies;
		if (delay <= HZ)
			schedule_timeout_interruptible(delay);

		/* there should be no signal, but oh well */
		if (signal_pending(current)) {
			printk(KERN_WARNING "windfarm: thread got sigl !\n");
			break;
		}
	}

	DBG("wf: thread stopped\n");

	return 0;
}

static void wf_start_thread(void)
{
	wf_thread = kthread_run(wf_thread_func, NULL, "kwindfarm");
	if (IS_ERR(wf_thread)) {
		printk(KERN_ERR "windfarm: failed to create thread,err %ld\n",
		       PTR_ERR(wf_thread));
		wf_thread = NULL;
	}
}


static void wf_stop_thread(void)
{
	if (wf_thread)
		kthread_stop(wf_thread);
	wf_thread = NULL;
}

/*
 * Controls
 */

static void wf_control_release(struct kref *kref)
{
	struct wf_control *ct = container_of(kref, struct wf_control, ref);

	DBG("wf: Deleting control %s\n", ct->name);

	if (ct->ops && ct->ops->release)
		ct->ops->release(ct);
	else
		kfree(ct);
}

static ssize_t wf_show_control(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
	s32 val = 0;
	int err;

	err = ctrl->ops->get_value(ctrl, &val);
	if (err < 0)
		return err;
	return sprintf(buf, "%d\n", val);
}

/* This is really only for debugging... */
static ssize_t wf_store_control(struct device *dev,
				struct device_attribute *attr,
				const char *buf, size_t count)
{
	struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
	int val;
	int err;
	char *endp;

	val = simple_strtoul(buf, &endp, 0);
	while (endp < buf + count && (*endp == ' ' || *endp == '\n'))
		++endp;
	if (endp - buf < count)
		return -EINVAL;
	err = ctrl->ops->set_value(ctrl, val);
	if (err < 0)
		return err;
	return count;
}

int wf_register_control(struct wf_control *new_ct)
{
	struct wf_control *ct;

	mutex_lock(&wf_lock);
	list_for_each_entry(ct, &wf_controls, link) {
		if (!strcmp(ct->name, new_ct->name)) {
			printk(KERN_WARNING "windfarm: trying to register"
			       " duplicate control %s\n", ct->name);
			mutex_unlock(&wf_lock);
			return -EEXIST;
		}
	}
	kref_init(&new_ct->ref);
	list_add(&new_ct->link, &wf_controls);

	new_ct->attr.attr.name = new_ct->name;
	new_ct->attr.attr.owner = THIS_MODULE;
	new_ct->attr.attr.mode = 0644;
	new_ct->attr.show = wf_show_control;
	new_ct->attr.store = wf_store_control;
	device_create_file(&wf_platform_device.dev, &new_ct->attr);

	DBG("wf: Registered control %s\n", new_ct->name);

	wf_notify(WF_EVENT_NEW_CONTROL, new_ct);
	mutex_unlock(&wf_lock);

	return 0;
}
EXPORT_SYMBOL_GPL(wf_register_control);

void wf_unregister_control(struct wf_control *ct)
{
	mutex_lock(&wf_lock);
	list_del(&ct->link);
	mutex_unlock(&wf_lock);

	DBG("wf: Unregistered control %s\n", ct->name);

	kref_put(&ct->ref, wf_control_release);
}
EXPORT_SYMBOL_GPL(wf_unregister_control);

struct wf_control * wf_find_control(const char *name)
{
	struct wf_control *ct;

	mutex_lock(&wf_lock);
	list_for_each_entry(ct, &wf_controls, link) {
		if (!strcmp(ct->name, name)) {
			if (wf_get_control(ct))
				ct = NULL;
			mutex_unlock(&wf_lock);
			return ct;
		}
	}
	mutex_unlock(&wf_lock);
	return NULL;
}
EXPORT_SYMBOL_GPL(wf_find_control);

int wf_get_control(struct wf_control *ct)
{
	if (!try_module_get(ct->ops->owner))
		return -ENODEV;
	kref_get(&ct->ref);
	return 0;
}
EXPORT_SYMBOL_GPL(wf_get_control);

void wf_put_control(struct wf_control *ct)
{
	struct module *mod = ct->ops->owner;
	kref_put(&ct->ref, wf_control_release);
	module_put(mod);
}
EXPORT_SYMBOL_GPL(wf_put_control);


/*
 * Sensors
 */


static void wf_sensor_release(struct kref *kref)
{
	struct wf_sensor *sr = container_of(kref, struct wf_sensor, ref);

	DBG("wf: Deleting sensor %s\n", sr->name);

	if (sr->ops && sr->ops->release)
		sr->ops->release(sr);
	else
		kfree(sr);
}

static ssize_t wf_show_sensor(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct wf_sensor *sens = container_of(attr, struct wf_sensor, attr);
	s32 val = 0;
	int err;

	err = sens->ops->get_value(sens, &val);
	if (err < 0)
		return err;
	return sprintf(buf, "%d.%03d\n", FIX32TOPRINT(val));
}

int wf_register_sensor(struct wf_sensor *new_sr)
{
	struct wf_sensor *sr;

	mutex_lock(&wf_lock);
	list_for_each_entry(sr, &wf_sensors, link) {
		if (!strcmp(sr->name, new_sr->name)) {
			printk(KERN_WARNING "windfarm: trying to register"
			       " duplicate sensor %s\n", sr->name);
			mutex_unlock(&wf_lock);
			return -EEXIST;
		}
	}
	kref_init(&new_sr->ref);
	list_add(&new_sr->link, &wf_sensors);

	new_sr->attr.attr.name = new_sr->name;
	new_sr->attr.attr.owner = THIS_MODULE;
	new_sr->attr.attr.mode = 0444;
	new_sr->attr.show = wf_show_sensor;
	new_sr->attr.store = NULL;
	device_create_file(&wf_platform_device.dev, &new_sr->attr);

	DBG("wf: Registered sensor %s\n", new_sr->name);

	wf_notify(WF_EVENT_NEW_SENSOR, new_sr);
	mutex_unlock(&wf_lock);

	return 0;
}
EXPORT_SYMBOL_GPL(wf_register_sensor);

void wf_unregister_sensor(struct wf_sensor *sr)
{
	mutex_lock(&wf_lock);
	list_del(&sr->link);
	mutex_unlock(&wf_lock);

	DBG("wf: Unregistered sensor %s\n", sr->name);

	wf_put_sensor(sr);
}
EXPORT_SYMBOL_GPL(wf_unregister_sensor);

struct wf_sensor * wf_find_sensor(const char *name)
{
	struct wf_sensor *sr;

	mutex_lock(&wf_lock);
	list_for_each_entry(sr, &wf_sensors, link) {
		if (!strcmp(sr->name, name)) {
			if (wf_get_sensor(sr))
				sr = NULL;
			mutex_unlock(&wf_lock);
			return sr;
		}
	}
	mutex_unlock(&wf_lock);
	return NULL;
}
EXPORT_SYMBOL_GPL(wf_find_sensor);

int wf_get_sensor(struct wf_sensor *sr)
{
	if (!try_module_get(sr->ops->owner))
		return -ENODEV;
	kref_get(&sr->ref);
	return 0;
}
EXPORT_SYMBOL_GPL(wf_get_sensor);

void wf_put_sensor(struct wf_sensor *sr)
{
	struct module *mod = sr->ops->owner;
	kref_put(&sr->ref, wf_sensor_release);
	module_put(mod);
}
EXPORT_SYMBOL_GPL(wf_put_sensor);


/*
 * Client & notification
 */

int wf_register_client(struct notifier_block *nb)
{
	int rc;
	struct wf_control *ct;
	struct wf_sensor *sr;

	mutex_lock(&wf_lock);
	rc = blocking_notifier_chain_register(&wf_client_list, nb);
	if (rc != 0)
		goto bail;
	wf_client_count++;
	list_for_each_entry(ct, &wf_controls, link)
		wf_notify(WF_EVENT_NEW_CONTROL, ct);
	list_for_each_entry(sr, &wf_sensors, link)
		wf_notify(WF_EVENT_NEW_SENSOR, sr);
	if (wf_client_count == 1)
		wf_start_thread();
 bail:
	mutex_unlock(&wf_lock);
	return rc;
}
EXPORT_SYMBOL_GPL(wf_register_client);

int wf_unregister_client(struct notifier_block *nb)
{
	mutex_lock(&wf_lock);
	blocking_notifier_chain_unregister(&wf_client_list, nb);
	wf_client_count++;
	if (wf_client_count == 0)
		wf_stop_thread();
	mutex_unlock(&wf_lock);

	return 0;
}
EXPORT_SYMBOL_GPL(wf_unregister_client);

void wf_set_overtemp(void)
{
	mutex_lock(&wf_lock);
	wf_overtemp++;
	if (wf_overtemp == 1) {
		printk(KERN_WARNING "windfarm: Overtemp condition detected !\n");
		wf_overtemp_counter = 0;
		wf_notify(WF_EVENT_OVERTEMP, NULL);
	}
	mutex_unlock(&wf_lock);
}
EXPORT_SYMBOL_GPL(wf_set_overtemp);

void wf_clear_overtemp(void)
{
	mutex_lock(&wf_lock);
	WARN_ON(wf_overtemp == 0);
	if (wf_overtemp == 0) {
		mutex_unlock(&wf_lock);
		return;
	}
	wf_overtemp--;
	if (wf_overtemp == 0) {
		printk(KERN_WARNING "windfarm: Overtemp condition cleared !\n");
		wf_notify(WF_EVENT_NORMALTEMP, NULL);
	}
	mutex_unlock(&wf_lock);
}
EXPORT_SYMBOL_GPL(wf_clear_overtemp);

int wf_is_overtemp(void)
{
	return (wf_overtemp != 0);
}
EXPORT_SYMBOL_GPL(wf_is_overtemp);

static int __init windfarm_core_init(void)
{
	DBG("wf: core loaded\n");

	/* Don't register on old machines that use therm_pm72 for now */
	if (machine_is_compatible("PowerMac7,2") ||
	    machine_is_compatible("PowerMac7,3") ||
	    machine_is_compatible("RackMac3,1"))
		return -ENODEV;
	platform_device_register(&wf_platform_device);
	return 0;
}

static void __exit windfarm_core_exit(void)
{
	BUG_ON(wf_client_count != 0);

	DBG("wf: core unloaded\n");

	platform_device_unregister(&wf_platform_device);
}


module_init(windfarm_core_init);
module_exit(windfarm_core_exit);

MODULE_AUTHOR("Benjamin Herrenschmidt <[email protected]>");
MODULE_DESCRIPTION("Core component of PowerMac thermal control");
MODULE_LICENSE("GPL");
Commit	Line	Data
75722d39 BH	1	/*
	2	* Windfarm PowerMac thermal control. Core
	3	*
	4	* (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
	5	* <[email protected]>
	6	*
	7	* Released under the term of the GNU GPL v2.
	8	*
	9	* This core code tracks the list of sensors & controls, register
	10	* clients, and holds the kernel thread used for control.
	11	*
	12	* TODO:
	13	*
	14	* Add some information about sensor/control type and data format to
	15	* sensors/controls, and have the sysfs attribute stuff be moved
	16	* generically here instead of hard coded in the platform specific
	17	* driver as it us currently
	18	*
	19	* This however requires solving some annoying lifetime issues with
	20	* sysfs which doesn't seem to have lifetime rules for struct attribute,
	21	* I may have to create full features kobjects for every sensor/control
	22	* instead which is a bit of an overkill imho
	23	*/
	24
	25	#include <linux/types.h>
	26	#include <linux/errno.h>
	27	#include <linux/kernel.h>
	28	#include <linux/init.h>
	29	#include <linux/spinlock.h>
	30	#include <linux/smp_lock.h>
	31	#include <linux/kthread.h>
	32	#include <linux/jiffies.h>
	33	#include <linux/reboot.h>
	34	#include <linux/device.h>
	35	#include <linux/platform_device.h>
837e9594	36	#include <linux/mutex.h>
75722d39	37
b55fafc5 BH	38	#include <asm/prom.h>
b55fafc5 BH	39
75722d39 BH	40	#include "windfarm.h"
	41
	42	#define VERSION "0.2"
	43
	44	#undef DEBUG
	45
	46	#ifdef DEBUG
	47	#define DBG(args...) printk(args)
	48	#else
	49	#define DBG(args...) do { } while(0)
	50	#endif
	51
	52	static LIST_HEAD(wf_controls);
	53	static LIST_HEAD(wf_sensors);
837e9594	54	static DEFINE_MUTEX(wf_lock);
e041c683	55	static BLOCKING_NOTIFIER_HEAD(wf_client_list);
75722d39 BH	56	static int wf_client_count;
	57	static unsigned int wf_overtemp;
	58	static unsigned int wf_overtemp_counter;
	59	struct task_struct *wf_thread;
	60
ac171c46 BH	61	static struct platform_device wf_platform_device = {
	62	.name = "windfarm",
	63	};
	64
75722d39 BH	65	/*
	66	* Utilities & tick thread
	67	*/
	68
	69	static inline void wf_notify(int event, void *param)
	70	{
e041c683	71	blocking_notifier_call_chain(&wf_client_list, event, param);
75722d39 BH	72	}
	73
	74	int wf_critical_overtemp(void)
	75	{
	76	static char * critical_overtemp_path = "/sbin/critical_overtemp";
	77	char *argv[] = { critical_overtemp_path, NULL };
	78	static char *envp[] = { "HOME=/",
	79	"TERM=linux",
	80	"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
	81	NULL };
	82
	83	return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
	84	}
	85	EXPORT_SYMBOL_GPL(wf_critical_overtemp);
	86
	87	static int wf_thread_func(void *data)
	88	{
	89	unsigned long next, delay;
	90
	91	next = jiffies;
	92
	93	DBG("wf: thread started\n");
	94
	95	while(!kthread_should_stop()) {
	96	try_to_freeze();
	97
	98	if (time_after_eq(jiffies, next)) {
	99	wf_notify(WF_EVENT_TICK, NULL);
	100	if (wf_overtemp) {
	101	wf_overtemp_counter++;
	102	/* 10 seconds overtemp, notify userland */
	103	if (wf_overtemp_counter > 10)
	104	wf_critical_overtemp();
	105	/* 30 seconds, shutdown */
	106	if (wf_overtemp_counter > 30) {
	107	printk(KERN_ERR "windfarm: Overtemp "
	108	"for more than 30"
	109	" seconds, shutting down\n");
	110	machine_power_off();
	111	}
	112	}
	113	next += HZ;
	114	}
	115
	116	delay = next - jiffies;
	117	if (delay <= HZ)
	118	schedule_timeout_interruptible(delay);
	119
	120	/* there should be no signal, but oh well */
	121	if (signal_pending(current)) {
	122	printk(KERN_WARNING "windfarm: thread got sigl !\n");
	123	break;
	124	}
	125	}
	126
	127	DBG("wf: thread stopped\n");
	128
	129	return 0;
	130	}
	131
	132	static void wf_start_thread(void)
	133	{
	134	wf_thread = kthread_run(wf_thread_func, NULL, "kwindfarm");
	135	if (IS_ERR(wf_thread)) {
136	printk(KERN_ERR "windfarm: failed to create thread,err %ld\n",
137	PTR_ERR(wf_thread));
138	wf_thread = NULL;
139	}
140	}
141
142
143	static void wf_stop_thread(void)
144	{
145	if (wf_thread)
146	kthread_stop(wf_thread);
147	wf_thread = NULL;
148	}
149
150	/*
151	* Controls
152	*/
153
154	static void wf_control_release(struct kref *kref)
155	{
156	struct wf_control *ct = container_of(kref, struct wf_control, ref);
157
158	DBG("wf: Deleting control %s\n", ct->name);
159
160	if (ct->ops && ct->ops->release)
161	ct->ops->release(ct);
162	else
163	kfree(ct);
164	}
165
ac171c46 BH	166	static ssize_t wf_show_control(struct device *dev,
	167	struct device_attribute attr, char buf)
	168	{
	169	struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
	170	s32 val = 0;
	171	int err;
	172
	173	err = ctrl->ops->get_value(ctrl, &val);
	174	if (err < 0)
	175	return err;
	176	return sprintf(buf, "%d\n", val);
	177	}
	178
	179	/* This is really only for debugging... */
	180	static ssize_t wf_store_control(struct device *dev,
	181	struct device_attribute *attr,
	182	const char *buf, size_t count)
	183	{
	184	struct wf_control *ctrl = container_of(attr, struct wf_control, attr);
	185	int val;
	186	int err;
	187	char *endp;
	188
	189	val = simple_strtoul(buf, &endp, 0);
	190	while (endp < buf + count && (endp == ' ' \|\| endp == '\n'))
	191	++endp;
	192	if (endp - buf < count)
	193	return -EINVAL;
	194	err = ctrl->ops->set_value(ctrl, val);
	195	if (err < 0)
	196	return err;
	197	return count;
	198	}
	199
75722d39 BH	200	int wf_register_control(struct wf_control *new_ct)
	201	{
	202	struct wf_control *ct;
	203
837e9594	204	mutex_lock(&wf_lock);
75722d39 BH	205	list_for_each_entry(ct, &wf_controls, link) {
	206	if (!strcmp(ct->name, new_ct->name)) {
	207	printk(KERN_WARNING "windfarm: trying to register"
	208	" duplicate control %s\n", ct->name);
837e9594	209	mutex_unlock(&wf_lock);
75722d39 BH	210	return -EEXIST;
	211	}
	212	}
	213	kref_init(&new_ct->ref);
	214	list_add(&new_ct->link, &wf_controls);
	215
ac171c46 BH	216	new_ct->attr.attr.name = new_ct->name;
	217	new_ct->attr.attr.owner = THIS_MODULE;
	218	new_ct->attr.attr.mode = 0644;
	219	new_ct->attr.show = wf_show_control;
	220	new_ct->attr.store = wf_store_control;
	221	device_create_file(&wf_platform_device.dev, &new_ct->attr);
	222
75722d39 BH	223	DBG("wf: Registered control %s\n", new_ct->name);
	224
	225	wf_notify(WF_EVENT_NEW_CONTROL, new_ct);
837e9594	226	mutex_unlock(&wf_lock);
75722d39 BH	227
	228	return 0;
	229	}
	230	EXPORT_SYMBOL_GPL(wf_register_control);
	231
	232	void wf_unregister_control(struct wf_control *ct)
	233	{
837e9594	234	mutex_lock(&wf_lock);
75722d39	235	list_del(&ct->link);
837e9594	236	mutex_unlock(&wf_lock);
75722d39 BH	237
	238	DBG("wf: Unregistered control %s\n", ct->name);
	239
	240	kref_put(&ct->ref, wf_control_release);
	241	}
	242	EXPORT_SYMBOL_GPL(wf_unregister_control);
	243
	244	struct wf_control * wf_find_control(const char *name)
	245	{
	246	struct wf_control *ct;
	247
837e9594	248	mutex_lock(&wf_lock);
75722d39 BH	249	list_for_each_entry(ct, &wf_controls, link) {
	250	if (!strcmp(ct->name, name)) {
	251	if (wf_get_control(ct))
	252	ct = NULL;
837e9594	253	mutex_unlock(&wf_lock);
75722d39 BH	254	return ct;
	255	}
	256	}
837e9594	257	mutex_unlock(&wf_lock);
75722d39 BH	258	return NULL;
	259	}
	260	EXPORT_SYMBOL_GPL(wf_find_control);
	261
	262	int wf_get_control(struct wf_control *ct)
	263	{
	264	if (!try_module_get(ct->ops->owner))
	265	return -ENODEV;
	266	kref_get(&ct->ref);
	267	return 0;
	268	}
	269	EXPORT_SYMBOL_GPL(wf_get_control);
	270
	271	void wf_put_control(struct wf_control *ct)
	272	{
	273	struct module *mod = ct->ops->owner;
	274	kref_put(&ct->ref, wf_control_release);
	275	module_put(mod);
	276	}
	277	EXPORT_SYMBOL_GPL(wf_put_control);
	278
	279
	280	/*
	281	* Sensors
	282	*/
	283
	284
	285	static void wf_sensor_release(struct kref *kref)
	286	{
	287	struct wf_sensor *sr = container_of(kref, struct wf_sensor, ref);
	288
	289	DBG("wf: Deleting sensor %s\n", sr->name);
	290
	291	if (sr->ops && sr->ops->release)
	292	sr->ops->release(sr);
	293	else
	294	kfree(sr);
	295	}
	296
ac171c46 BH	297	static ssize_t wf_show_sensor(struct device *dev,
	298	struct device_attribute attr, char buf)
	299	{
	300	struct wf_sensor *sens = container_of(attr, struct wf_sensor, attr);
	301	s32 val = 0;
	302	int err;
	303
	304	err = sens->ops->get_value(sens, &val);
	305	if (err < 0)
	306	return err;
	307	return sprintf(buf, "%d.%03d\n", FIX32TOPRINT(val));
	308	}
	309
75722d39 BH	310	int wf_register_sensor(struct wf_sensor *new_sr)
	311	{
	312	struct wf_sensor *sr;
	313
837e9594	314	mutex_lock(&wf_lock);
75722d39 BH	315	list_for_each_entry(sr, &wf_sensors, link) {
	316	if (!strcmp(sr->name, new_sr->name)) {
	317	printk(KERN_WARNING "windfarm: trying to register"
	318	" duplicate sensor %s\n", sr->name);
837e9594	319	mutex_unlock(&wf_lock);
75722d39 BH	320	return -EEXIST;
	321	}
	322	}
	323	kref_init(&new_sr->ref);
	324	list_add(&new_sr->link, &wf_sensors);
	325
ac171c46 BH	326	new_sr->attr.attr.name = new_sr->name;
	327	new_sr->attr.attr.owner = THIS_MODULE;
	328	new_sr->attr.attr.mode = 0444;
	329	new_sr->attr.show = wf_show_sensor;
	330	new_sr->attr.store = NULL;
	331	device_create_file(&wf_platform_device.dev, &new_sr->attr);
	332
75722d39 BH	333	DBG("wf: Registered sensor %s\n", new_sr->name);
	334
	335	wf_notify(WF_EVENT_NEW_SENSOR, new_sr);
837e9594	336	mutex_unlock(&wf_lock);
75722d39 BH	337
	338	return 0;
	339	}
	340	EXPORT_SYMBOL_GPL(wf_register_sensor);
	341
	342	void wf_unregister_sensor(struct wf_sensor *sr)
	343	{
837e9594	344	mutex_lock(&wf_lock);
75722d39	345	list_del(&sr->link);
837e9594	346	mutex_unlock(&wf_lock);
75722d39 BH	347
	348	DBG("wf: Unregistered sensor %s\n", sr->name);
	349
	350	wf_put_sensor(sr);
	351	}
	352	EXPORT_SYMBOL_GPL(wf_unregister_sensor);
	353
	354	struct wf_sensor * wf_find_sensor(const char *name)
	355	{
	356	struct wf_sensor *sr;
	357
837e9594	358	mutex_lock(&wf_lock);
75722d39 BH	359	list_for_each_entry(sr, &wf_sensors, link) {
	360	if (!strcmp(sr->name, name)) {
	361	if (wf_get_sensor(sr))
	362	sr = NULL;
837e9594	363	mutex_unlock(&wf_lock);
75722d39 BH	364	return sr;
	365	}
	366	}
837e9594	367	mutex_unlock(&wf_lock);
75722d39 BH	368	return NULL;
	369	}
	370	EXPORT_SYMBOL_GPL(wf_find_sensor);
	371
	372	int wf_get_sensor(struct wf_sensor *sr)
	373	{
	374	if (!try_module_get(sr->ops->owner))
	375	return -ENODEV;
	376	kref_get(&sr->ref);
	377	return 0;
	378	}
	379	EXPORT_SYMBOL_GPL(wf_get_sensor);
	380
	381	void wf_put_sensor(struct wf_sensor *sr)
	382	{
	383	struct module *mod = sr->ops->owner;
	384	kref_put(&sr->ref, wf_sensor_release);
	385	module_put(mod);
	386	}
	387	EXPORT_SYMBOL_GPL(wf_put_sensor);
	388
	389
	390	/*
	391	* Client & notification
	392	*/
	393
	394	int wf_register_client(struct notifier_block *nb)
	395	{
	396	int rc;
	397	struct wf_control *ct;
	398	struct wf_sensor *sr;
	399
837e9594	400	mutex_lock(&wf_lock);
e041c683	401	rc = blocking_notifier_chain_register(&wf_client_list, nb);
75722d39 BH	402	if (rc != 0)
	403	goto bail;
	404	wf_client_count++;
	405	list_for_each_entry(ct, &wf_controls, link)
	406	wf_notify(WF_EVENT_NEW_CONTROL, ct);
	407	list_for_each_entry(sr, &wf_sensors, link)
	408	wf_notify(WF_EVENT_NEW_SENSOR, sr);
	409	if (wf_client_count == 1)
	410	wf_start_thread();
	411	bail:
837e9594	412	mutex_unlock(&wf_lock);
75722d39 BH	413	return rc;
	414	}
	415	EXPORT_SYMBOL_GPL(wf_register_client);
	416
	417	int wf_unregister_client(struct notifier_block *nb)
	418	{
837e9594	419	mutex_lock(&wf_lock);
e041c683	420	blocking_notifier_chain_unregister(&wf_client_list, nb);
75722d39 BH	421	wf_client_count++;
	422	if (wf_client_count == 0)
	423	wf_stop_thread();
837e9594	424	mutex_unlock(&wf_lock);
75722d39 BH	425
	426	return 0;
	427	}
	428	EXPORT_SYMBOL_GPL(wf_unregister_client);
	429
	430	void wf_set_overtemp(void)
	431	{
837e9594	432	mutex_lock(&wf_lock);
75722d39 BH	433	wf_overtemp++;
	434	if (wf_overtemp == 1) {
	435	printk(KERN_WARNING "windfarm: Overtemp condition detected !\n");
	436	wf_overtemp_counter = 0;
	437	wf_notify(WF_EVENT_OVERTEMP, NULL);
	438	}
837e9594	439	mutex_unlock(&wf_lock);
75722d39 BH	440	}
	441	EXPORT_SYMBOL_GPL(wf_set_overtemp);
	442
	443	void wf_clear_overtemp(void)
	444	{
837e9594	445	mutex_lock(&wf_lock);
75722d39 BH	446	WARN_ON(wf_overtemp == 0);
75722d39 BH	447	if (wf_overtemp == 0) {
837e9594	448	mutex_unlock(&wf_lock);
75722d39 BH	449	return;
	450	}
	451	wf_overtemp--;
	452	if (wf_overtemp == 0) {
	453	printk(KERN_WARNING "windfarm: Overtemp condition cleared !\n");
	454	wf_notify(WF_EVENT_NORMALTEMP, NULL);
	455	}
837e9594	456	mutex_unlock(&wf_lock);
75722d39 BH	457	}
	458	EXPORT_SYMBOL_GPL(wf_clear_overtemp);
	459
	460	int wf_is_overtemp(void)
	461	{
	462	return (wf_overtemp != 0);
	463	}
	464	EXPORT_SYMBOL_GPL(wf_is_overtemp);
	465
75722d39 BH	466	static int __init windfarm_core_init(void)
	467	{
	468	DBG("wf: core loaded\n");
	469
b55fafc5 BH	470	/* Don't register on old machines that use therm_pm72 for now */
	471	if (machine_is_compatible("PowerMac7,2") \|\|
	472	machine_is_compatible("PowerMac7,3") \|\|
	473	machine_is_compatible("RackMac3,1"))
	474	return -ENODEV;
75722d39 BH	475	platform_device_register(&wf_platform_device);
	476	return 0;
	477	}
	478
	479	static void __exit windfarm_core_exit(void)
	480	{
	481	BUG_ON(wf_client_count != 0);
	482
	483	DBG("wf: core unloaded\n");
	484
	485	platform_device_unregister(&wf_platform_device);
	486	}
	487
	488
	489	module_init(windfarm_core_init);
	490	module_exit(windfarm_core_exit);
	491
	492	MODULE_AUTHOR("Benjamin Herrenschmidt <[email protected]>");
	493	MODULE_DESCRIPTION("Core component of PowerMac thermal control");
	494	MODULE_LICENSE("GPL");
	495