[net-next-2.6.git] / arch / sh / drivers / heartbeat.c

/*
 * Generic heartbeat driver for regular LED banks
 *
 * Copyright (C) 2007 - 2010  Paul Mundt
 *
 * Most SH reference boards include a number of individual LEDs that can
 * be independently controlled (either via a pre-defined hardware
 * function or via the LED class, if desired -- the hardware tends to
 * encapsulate some of the same "triggers" that the LED class supports,
 * so there's not too much value in it).
 *
 * Additionally, most of these boards also have a LED bank that we've
 * traditionally used for strobing the load average. This use case is
 * handled by this driver, rather than giving each LED bit position its
 * own struct device.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <asm/heartbeat.h>

#define DRV_NAME "heartbeat"
#define DRV_VERSION "0.1.2"

static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };

static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
					unsigned bit, unsigned int inverted)
{
	unsigned int new;

	new = (1 << hd->bit_pos[bit]);
	if (inverted)
		new = ~new;

	new &= hd->mask;

	switch (hd->regsize) {
	case 32:
		new |= ioread32(hd->base) & ~hd->mask;
		iowrite32(new, hd->base);
		break;
	case 16:
		new |= ioread16(hd->base) & ~hd->mask;
		iowrite16(new, hd->base);
		break;
	default:
		new |= ioread8(hd->base) & ~hd->mask;
		iowrite8(new, hd->base);
		break;
	}
}

static void heartbeat_timer(unsigned long data)
{
	struct heartbeat_data *hd = (struct heartbeat_data *)data;
	static unsigned bit = 0, up = 1;

	heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);

	bit += up;
	if ((bit == 0) || (bit == (hd->nr_bits)-1))
		up = -up;

	mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
			((avenrun[0] / 5) + (3 << FSHIFT)))));
}

static int heartbeat_drv_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct heartbeat_data *hd;
	int i;

	if (unlikely(pdev->num_resources != 1)) {
		dev_err(&pdev->dev, "invalid number of resources\n");
		return -EINVAL;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (unlikely(res == NULL)) {
		dev_err(&pdev->dev, "invalid resource\n");
		return -EINVAL;
	}

	if (pdev->dev.platform_data) {
		hd = pdev->dev.platform_data;
	} else {
		hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
		if (unlikely(!hd))
			return -ENOMEM;
	}

	hd->base = ioremap_nocache(res->start, resource_size(res));
	if (unlikely(!hd->base)) {
		dev_err(&pdev->dev, "ioremap failed\n");

		if (!pdev->dev.platform_data)
			kfree(hd);

		return -ENXIO;
	}

	if (!hd->nr_bits) {
		hd->bit_pos = default_bit_pos;
		hd->nr_bits = ARRAY_SIZE(default_bit_pos);
	}

	hd->mask = 0;
	for (i = 0; i < hd->nr_bits; i++)
		hd->mask |= (1 << hd->bit_pos[i]);

	if (!hd->regsize) {
		switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
		case IORESOURCE_MEM_32BIT:
			hd->regsize = 32;
			break;
		case IORESOURCE_MEM_16BIT:
			hd->regsize = 16;
			break;
		case IORESOURCE_MEM_8BIT:
		default:
			hd->regsize = 8;
			break;
		}
	}

	setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd);
	platform_set_drvdata(pdev, hd);

	return mod_timer(&hd->timer, jiffies + 1);
}

static int heartbeat_drv_remove(struct platform_device *pdev)
{
	struct heartbeat_data *hd = platform_get_drvdata(pdev);

	del_timer_sync(&hd->timer);
	iounmap(hd->base);

	platform_set_drvdata(pdev, NULL);

	if (!pdev->dev.platform_data)
		kfree(hd);

	return 0;
}

static struct platform_driver heartbeat_driver = {
	.probe		= heartbeat_drv_probe,
	.remove		= heartbeat_drv_remove,
	.driver		= {
		.name	= DRV_NAME,
	},
};

static int __init heartbeat_init(void)
{
	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
	return platform_driver_register(&heartbeat_driver);
}

static void __exit heartbeat_exit(void)
{
	platform_driver_unregister(&heartbeat_driver);
}
module_init(heartbeat_init);
module_exit(heartbeat_exit);

MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Paul Mundt");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
401e9093 PM	1	/*
	2	* Generic heartbeat driver for regular LED banks
	3	*
10ab92d8	4	* Copyright (C) 2007 - 2010 Paul Mundt
401e9093 PM	5	*
	6	* Most SH reference boards include a number of individual LEDs that can
	7	* be independently controlled (either via a pre-defined hardware
	8	* function or via the LED class, if desired -- the hardware tends to
	9	* encapsulate some of the same "triggers" that the LED class supports,
	10	* so there's not too much value in it).
	11	*
	12	* Additionally, most of these boards also have a LED bank that we've
	13	* traditionally used for strobing the load average. This use case is
	14	* handled by this driver, rather than giving each LED bit position its
	15	* own struct device.
	16	*
	17	* This file is subject to the terms and conditions of the GNU General Public
	18	* License. See the file "COPYING" in the main directory of this archive
	19	* for more details.
	20	*/
	21	#include <linux/init.h>
	22	#include <linux/module.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/sched.h>
	25	#include <linux/timer.h>
	26	#include <linux/io.h>
5a0e3ad6	27	#include <linux/slab.h>
8786c952	28	#include <asm/heartbeat.h>
401e9093 PM	29
401e9093 PM	30	#define DRV_NAME "heartbeat"
10ab92d8	31	#define DRV_VERSION "0.1.2"
401e9093	32
8786c952 PM	33	static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
	34
	35	static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
	36	unsigned bit, unsigned int inverted)
	37	{
	38	unsigned int new;
	39
	40	new = (1 << hd->bit_pos[bit]);
	41	if (inverted)
	42	new = ~new;
	43
e174d130 KM	44	new &= hd->mask;
e174d130 KM	45
8786c952 PM	46	switch (hd->regsize) {
8786c952 PM	47	case 32:
e174d130	48	new \|= ioread32(hd->base) & ~hd->mask;
8786c952 PM	49	iowrite32(new, hd->base);
	50	break;
	51	case 16:
e174d130	52	new \|= ioread16(hd->base) & ~hd->mask;
8786c952 PM	53	iowrite16(new, hd->base);
	54	break;
	55	default:
e174d130	56	new \|= ioread8(hd->base) & ~hd->mask;
8786c952 PM	57	iowrite8(new, hd->base);
	58	break;
	59	}
	60	}
401e9093 PM	61
	62	static void heartbeat_timer(unsigned long data)
	63	{
	64	struct heartbeat_data hd = (struct heartbeat_data )data;
	65	static unsigned bit = 0, up = 1;
	66
8786c952 PM	67	heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
8786c952 PM	68
f6072896	69	bit += up;
8786c952	70	if ((bit == 0) \|\| (bit == (hd->nr_bits)-1))
f6072896	71	up = -up;
401e9093 PM	72
	73	mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
	74	((avenrun[0] / 5) + (3 << FSHIFT)))));
	75	}
	76
	77	static int heartbeat_drv_probe(struct platform_device *pdev)
	78	{
	79	struct resource *res;
	80	struct heartbeat_data *hd;
e174d130	81	int i;
401e9093 PM	82
	83	if (unlikely(pdev->num_resources != 1)) {
	84	dev_err(&pdev->dev, "invalid number of resources\n");
	85	return -EINVAL;
	86	}
	87
	88	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	89	if (unlikely(res == NULL)) {
	90	dev_err(&pdev->dev, "invalid resource\n");
	91	return -EINVAL;
	92	}
	93
401e9093	94	if (pdev->dev.platform_data) {
8786c952	95	hd = pdev->dev.platform_data;
401e9093	96	} else {
8786c952 PM	97	hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
	98	if (unlikely(!hd))
	99	return -ENOMEM;
	100	}
	101
10ab92d8	102	hd->base = ioremap_nocache(res->start, resource_size(res));
1de83e94	103	if (unlikely(!hd->base)) {
8786c952 PM	104	dev_err(&pdev->dev, "ioremap failed\n");
	105
	106	if (!pdev->dev.platform_data)
	107	kfree(hd);
	108
	109	return -ENXIO;
	110	}
401e9093	111
8786c952 PM	112	if (!hd->nr_bits) {
	113	hd->bit_pos = default_bit_pos;
	114	hd->nr_bits = ARRAY_SIZE(default_bit_pos);
401e9093 PM	115	}
401e9093 PM	116
e174d130 KM	117	hd->mask = 0;
	118	for (i = 0; i < hd->nr_bits; i++)
	119	hd->mask \|= (1 << hd->bit_pos[i]);
	120
10ab92d8 PM	121	if (!hd->regsize) {
	122	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	123	case IORESOURCE_MEM_32BIT:
	124	hd->regsize = 32;
	125	break;
	126	case IORESOURCE_MEM_16BIT:
	127	hd->regsize = 16;
	128	break;
	129	case IORESOURCE_MEM_8BIT:
	130	default:
	131	hd->regsize = 8;
	132	break;
	133	}
	134	}
401e9093 PM	135
	136	setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd);
	137	platform_set_drvdata(pdev, hd);
	138
	139	return mod_timer(&hd->timer, jiffies + 1);
	140	}
	141
	142	static int heartbeat_drv_remove(struct platform_device *pdev)
	143	{
	144	struct heartbeat_data *hd = platform_get_drvdata(pdev);
	145
	146	del_timer_sync(&hd->timer);
8786c952	147	iounmap(hd->base);
401e9093 PM	148
	149	platform_set_drvdata(pdev, NULL);
	150
8786c952 PM	151	if (!pdev->dev.platform_data)
8786c952 PM	152	kfree(hd);
401e9093 PM	153
	154	return 0;
	155	}
	156
	157	static struct platform_driver heartbeat_driver = {
	158	.probe = heartbeat_drv_probe,
	159	.remove = heartbeat_drv_remove,
	160	.driver = {
	161	.name = DRV_NAME,
	162	},
	163	};
	164
	165	static int __init heartbeat_init(void)
	166	{
	167	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
	168	return platform_driver_register(&heartbeat_driver);
	169	}
	170
	171	static void __exit heartbeat_exit(void)
	172	{
	173	platform_driver_unregister(&heartbeat_driver);
	174	}
	175	module_init(heartbeat_init);
	176	module_exit(heartbeat_exit);
	177
	178	MODULE_VERSION(DRV_VERSION);
	179	MODULE_AUTHOR("Paul Mundt");
839cd310	180	MODULE_LICENSE("GPL v2");