[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / macintosh / windfarm_cpufreq_clamp.c

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/cpufreq.h>

#include <asm/prom.h>

#include "windfarm.h"

#define VERSION "0.3"

static int clamped;
static struct wf_control *clamp_control;

static int clamp_notifier_call(struct notifier_block *self,
			       unsigned long event, void *data)
{
	struct cpufreq_policy *p = data;
	unsigned long max_freq;

	if (event != CPUFREQ_ADJUST)
		return 0;

	max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
	cpufreq_verify_within_limits(p, 0, max_freq);

	return 0;
}

static struct notifier_block clamp_notifier = {
	.notifier_call = clamp_notifier_call,
};

static int clamp_set(struct wf_control *ct, s32 value)
{
	if (value)
		printk(KERN_INFO "windfarm: Clamping CPU frequency to "
		       "minimum !\n");
	else
		printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
	clamped = value;
	cpufreq_update_policy(0);
	return 0;
}

static int clamp_get(struct wf_control *ct, s32 *value)
{
	*value = clamped;
	return 0;
}

static s32 clamp_min(struct wf_control *ct)
{
	return 0;
}

static s32 clamp_max(struct wf_control *ct)
{
	return 1;
}

static struct wf_control_ops clamp_ops = {
	.set_value	= clamp_set,
	.get_value	= clamp_get,
	.get_min	= clamp_min,
	.get_max	= clamp_max,
	.owner		= THIS_MODULE,
};

static int __init wf_cpufreq_clamp_init(void)
{
	struct wf_control *clamp;

	clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
	if (clamp == NULL)
		return -ENOMEM;
	cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
	clamp->ops = &clamp_ops;
	clamp->name = "cpufreq-clamp";
	if (wf_register_control(clamp))
		goto fail;
	clamp_control = clamp;
	return 0;
 fail:
	kfree(clamp);
	return -ENODEV;
}

static void __exit wf_cpufreq_clamp_exit(void)
{
	if (clamp_control)
		wf_unregister_control(clamp_control);
}


module_init(wf_cpufreq_clamp_init);
module_exit(wf_cpufreq_clamp_exit);

MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
MODULE_LICENSE("GPL");
Commit	Line	Data
75722d39 BH	1	#include <linux/types.h>
	2	#include <linux/errno.h>
	3	#include <linux/kernel.h>
	4	#include <linux/delay.h>
	5	#include <linux/slab.h>
	6	#include <linux/init.h>
	7	#include <linux/wait.h>
	8	#include <linux/cpufreq.h>
	9
b55fafc5 BH	10	#include <asm/prom.h>
b55fafc5 BH	11
75722d39 BH	12	#include "windfarm.h"
	13
	14	#define VERSION "0.3"
	15
	16	static int clamped;
	17	static struct wf_control *clamp_control;
	18
	19	static int clamp_notifier_call(struct notifier_block *self,
	20	unsigned long event, void *data)
	21	{
	22	struct cpufreq_policy *p = data;
	23	unsigned long max_freq;
	24
	25	if (event != CPUFREQ_ADJUST)
	26	return 0;
	27
	28	max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
	29	cpufreq_verify_within_limits(p, 0, max_freq);
	30
	31	return 0;
	32	}
	33
	34	static struct notifier_block clamp_notifier = {
	35	.notifier_call = clamp_notifier_call,
	36	};
	37
	38	static int clamp_set(struct wf_control *ct, s32 value)
	39	{
	40	if (value)
	41	printk(KERN_INFO "windfarm: Clamping CPU frequency to "
	42	"minimum !\n");
	43	else
	44	printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
	45	clamped = value;
	46	cpufreq_update_policy(0);
	47	return 0;
	48	}
	49
	50	static int clamp_get(struct wf_control ct, s32 value)
	51	{
	52	*value = clamped;
	53	return 0;
	54	}
	55
	56	static s32 clamp_min(struct wf_control *ct)
	57	{
	58	return 0;
	59	}
	60
	61	static s32 clamp_max(struct wf_control *ct)
	62	{
	63	return 1;
	64	}
	65
	66	static struct wf_control_ops clamp_ops = {
	67	.set_value = clamp_set,
	68	.get_value = clamp_get,
	69	.get_min = clamp_min,
	70	.get_max = clamp_max,
	71	.owner = THIS_MODULE,
	72	};
	73
	74	static int __init wf_cpufreq_clamp_init(void)
	75	{
76	struct wf_control *clamp;
77
78	clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
79	if (clamp == NULL)
80	return -ENOMEM;
81	cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
82	clamp->ops = &clamp_ops;
83	clamp->name = "cpufreq-clamp";
84	if (wf_register_control(clamp))
85	goto fail;
86	clamp_control = clamp;
87	return 0;
88	fail:
89	kfree(clamp);
90	return -ENODEV;
91	}
92
93	static void __exit wf_cpufreq_clamp_exit(void)
94	{
95	if (clamp_control)
96	wf_unregister_control(clamp_control);
97	}
98
99
100	module_init(wf_cpufreq_clamp_init);
101	module_exit(wf_cpufreq_clamp_exit);
102
103	MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
104	MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
105	MODULE_LICENSE("GPL");
106