[deliverable/linux.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 <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>
8786c952	27	#include <asm/heartbeat.h>
401e9093 PM	28
401e9093 PM	29	#define DRV_NAME "heartbeat"
10ab92d8	30	#define DRV_VERSION "0.1.2"
401e9093	31
8786c952 PM	32	static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
	33
	34	static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
	35	unsigned bit, unsigned int inverted)
	36	{
	37	unsigned int new;
	38
	39	new = (1 << hd->bit_pos[bit]);
	40	if (inverted)
	41	new = ~new;
	42
e174d130 KM	43	new &= hd->mask;
e174d130 KM	44
8786c952 PM	45	switch (hd->regsize) {
8786c952 PM	46	case 32:
e174d130	47	new \|= ioread32(hd->base) & ~hd->mask;
8786c952 PM	48	iowrite32(new, hd->base);
	49	break;
	50	case 16:
e174d130	51	new \|= ioread16(hd->base) & ~hd->mask;
8786c952 PM	52	iowrite16(new, hd->base);
	53	break;
	54	default:
e174d130	55	new \|= ioread8(hd->base) & ~hd->mask;
8786c952 PM	56	iowrite8(new, hd->base);
	57	break;
	58	}
	59	}
401e9093 PM	60
	61	static void heartbeat_timer(unsigned long data)
	62	{
	63	struct heartbeat_data hd = (struct heartbeat_data )data;
	64	static unsigned bit = 0, up = 1;
	65
8786c952 PM	66	heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
8786c952 PM	67
f6072896	68	bit += up;
8786c952	69	if ((bit == 0) \|\| (bit == (hd->nr_bits)-1))
f6072896	70	up = -up;
401e9093 PM	71
	72	mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
	73	((avenrun[0] / 5) + (3 << FSHIFT)))));
	74	}
	75
	76	static int heartbeat_drv_probe(struct platform_device *pdev)
	77	{
	78	struct resource *res;
	79	struct heartbeat_data *hd;
e174d130	80	int i;
401e9093 PM	81
	82	if (unlikely(pdev->num_resources != 1)) {
	83	dev_err(&pdev->dev, "invalid number of resources\n");
	84	return -EINVAL;
	85	}
	86
	87	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	88	if (unlikely(res == NULL)) {
	89	dev_err(&pdev->dev, "invalid resource\n");
	90	return -EINVAL;
	91	}
	92
401e9093	93	if (pdev->dev.platform_data) {
8786c952	94	hd = pdev->dev.platform_data;
401e9093	95	} else {
8786c952 PM	96	hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
	97	if (unlikely(!hd))
	98	return -ENOMEM;
	99	}
	100
10ab92d8	101	hd->base = ioremap_nocache(res->start, resource_size(res));
1de83e94	102	if (unlikely(!hd->base)) {
8786c952 PM	103	dev_err(&pdev->dev, "ioremap failed\n");
	104
	105	if (!pdev->dev.platform_data)
	106	kfree(hd);
	107
	108	return -ENXIO;
	109	}
401e9093	110
8786c952 PM	111	if (!hd->nr_bits) {
	112	hd->bit_pos = default_bit_pos;
	113	hd->nr_bits = ARRAY_SIZE(default_bit_pos);
401e9093 PM	114	}
401e9093 PM	115
e174d130 KM	116	hd->mask = 0;
	117	for (i = 0; i < hd->nr_bits; i++)
	118	hd->mask \|= (1 << hd->bit_pos[i]);
	119
10ab92d8 PM	120	if (!hd->regsize) {
	121	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	122	case IORESOURCE_MEM_32BIT:
	123	hd->regsize = 32;
	124	break;
	125	case IORESOURCE_MEM_16BIT:
	126	hd->regsize = 16;
	127	break;
	128	case IORESOURCE_MEM_8BIT:
	129	default:
	130	hd->regsize = 8;
	131	break;
	132	}
	133	}
401e9093 PM	134
	135	setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd);
	136	platform_set_drvdata(pdev, hd);
	137
	138	return mod_timer(&hd->timer, jiffies + 1);
	139	}
	140
	141	static int heartbeat_drv_remove(struct platform_device *pdev)
	142	{
	143	struct heartbeat_data *hd = platform_get_drvdata(pdev);
	144
	145	del_timer_sync(&hd->timer);
8786c952	146	iounmap(hd->base);
401e9093 PM	147
	148	platform_set_drvdata(pdev, NULL);
	149
8786c952 PM	150	if (!pdev->dev.platform_data)
8786c952 PM	151	kfree(hd);
401e9093 PM	152
	153	return 0;
	154	}
	155
	156	static struct platform_driver heartbeat_driver = {
	157	.probe = heartbeat_drv_probe,
	158	.remove = heartbeat_drv_remove,
	159	.driver = {
	160	.name = DRV_NAME,
	161	},
	162	};
	163
	164	static int __init heartbeat_init(void)
	165	{
	166	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
	167	return platform_driver_register(&heartbeat_driver);
	168	}
	169
	170	static void __exit heartbeat_exit(void)
	171	{
	172	platform_driver_unregister(&heartbeat_driver);
	173	}
	174	module_init(heartbeat_init);
	175	module_exit(heartbeat_exit);
	176
	177	MODULE_VERSION(DRV_VERSION);
	178	MODULE_AUTHOR("Paul Mundt");
839cd310	179	MODULE_LICENSE("GPL v2");