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v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic heartbeat driver for regular LED banks
  4 *
  5 * Copyright (C) 2007 - 2010  Paul Mundt
  6 *
  7 * Most SH reference boards include a number of individual LEDs that can
  8 * be independently controlled (either via a pre-defined hardware
  9 * function or via the LED class, if desired -- the hardware tends to
 10 * encapsulate some of the same "triggers" that the LED class supports,
 11 * so there's not too much value in it).
 12 *
 13 * Additionally, most of these boards also have a LED bank that we've
 14 * traditionally used for strobing the load average. This use case is
 15 * handled by this driver, rather than giving each LED bit position its
 16 * own struct device.
 17 */
 18#include <linux/init.h>
 19#include <linux/platform_device.h>
 20#include <linux/sched.h>
 21#include <linux/sched/loadavg.h>
 22#include <linux/timer.h>
 23#include <linux/io.h>
 24#include <linux/slab.h>
 25#include <asm/heartbeat.h>
 26
 27#define DRV_NAME "heartbeat"
 28#define DRV_VERSION "0.1.2"
 29
 30static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
 31
 32static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
 33					unsigned bit, unsigned int inverted)
 34{
 35	unsigned int new;
 36
 37	new = (1 << hd->bit_pos[bit]);
 38	if (inverted)
 39		new = ~new;
 40
 41	new &= hd->mask;
 42
 43	switch (hd->regsize) {
 44	case 32:
 45		new |= ioread32(hd->base) & ~hd->mask;
 46		iowrite32(new, hd->base);
 47		break;
 48	case 16:
 49		new |= ioread16(hd->base) & ~hd->mask;
 50		iowrite16(new, hd->base);
 51		break;
 52	default:
 53		new |= ioread8(hd->base) & ~hd->mask;
 54		iowrite8(new, hd->base);
 55		break;
 56	}
 57}
 58
 59static void heartbeat_timer(struct timer_list *t)
 60{
 61	struct heartbeat_data *hd = from_timer(hd, t, timer);
 62	static unsigned bit = 0, up = 1;
 63
 64	heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
 65
 66	bit += up;
 67	if ((bit == 0) || (bit == (hd->nr_bits)-1))
 68		up = -up;
 69
 70	mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
 71			((avenrun[0] / 5) + (3 << FSHIFT)))));
 72}
 73
 74static int heartbeat_drv_probe(struct platform_device *pdev)
 75{
 76	struct resource *res;
 77	struct heartbeat_data *hd;
 78	int i;
 79
 80	if (unlikely(pdev->num_resources != 1)) {
 81		dev_err(&pdev->dev, "invalid number of resources\n");
 82		return -EINVAL;
 83	}
 84
 85	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 86	if (unlikely(res == NULL)) {
 87		dev_err(&pdev->dev, "invalid resource\n");
 88		return -EINVAL;
 89	}
 90
 91	if (pdev->dev.platform_data) {
 92		hd = pdev->dev.platform_data;
 93	} else {
 94		hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
 95		if (unlikely(!hd))
 96			return -ENOMEM;
 97	}
 98
 99	hd->base = ioremap(res->start, resource_size(res));
100	if (unlikely(!hd->base)) {
101		dev_err(&pdev->dev, "ioremap failed\n");
102
103		if (!pdev->dev.platform_data)
104			kfree(hd);
105
106		return -ENXIO;
107	}
108
109	if (!hd->nr_bits) {
110		hd->bit_pos = default_bit_pos;
111		hd->nr_bits = ARRAY_SIZE(default_bit_pos);
112	}
113
114	hd->mask = 0;
115	for (i = 0; i < hd->nr_bits; i++)
116		hd->mask |= (1 << hd->bit_pos[i]);
117
118	if (!hd->regsize) {
119		switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
120		case IORESOURCE_MEM_32BIT:
121			hd->regsize = 32;
122			break;
123		case IORESOURCE_MEM_16BIT:
124			hd->regsize = 16;
125			break;
126		case IORESOURCE_MEM_8BIT:
127		default:
128			hd->regsize = 8;
129			break;
130		}
131	}
132
133	timer_setup(&hd->timer, heartbeat_timer, 0);
134	platform_set_drvdata(pdev, hd);
135
136	return mod_timer(&hd->timer, jiffies + 1);
137}
138
139static struct platform_driver heartbeat_driver = {
140	.probe		= heartbeat_drv_probe,
141	.driver		= {
142		.name			= DRV_NAME,
143		.suppress_bind_attrs	= true,
144	},
145};
146
147static int __init heartbeat_init(void)
148{
149	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
150	return platform_driver_register(&heartbeat_driver);
151}
152device_initcall(heartbeat_init);
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic heartbeat driver for regular LED banks
  4 *
  5 * Copyright (C) 2007 - 2010  Paul Mundt
  6 *
  7 * Most SH reference boards include a number of individual LEDs that can
  8 * be independently controlled (either via a pre-defined hardware
  9 * function or via the LED class, if desired -- the hardware tends to
 10 * encapsulate some of the same "triggers" that the LED class supports,
 11 * so there's not too much value in it).
 12 *
 13 * Additionally, most of these boards also have a LED bank that we've
 14 * traditionally used for strobing the load average. This use case is
 15 * handled by this driver, rather than giving each LED bit position its
 16 * own struct device.
 17 */
 18#include <linux/init.h>
 19#include <linux/platform_device.h>
 20#include <linux/sched.h>
 21#include <linux/sched/loadavg.h>
 22#include <linux/timer.h>
 23#include <linux/io.h>
 24#include <linux/slab.h>
 25#include <asm/heartbeat.h>
 26
 27#define DRV_NAME "heartbeat"
 28#define DRV_VERSION "0.1.2"
 29
 30static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
 31
 32static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
 33					unsigned bit, unsigned int inverted)
 34{
 35	unsigned int new;
 36
 37	new = (1 << hd->bit_pos[bit]);
 38	if (inverted)
 39		new = ~new;
 40
 41	new &= hd->mask;
 42
 43	switch (hd->regsize) {
 44	case 32:
 45		new |= ioread32(hd->base) & ~hd->mask;
 46		iowrite32(new, hd->base);
 47		break;
 48	case 16:
 49		new |= ioread16(hd->base) & ~hd->mask;
 50		iowrite16(new, hd->base);
 51		break;
 52	default:
 53		new |= ioread8(hd->base) & ~hd->mask;
 54		iowrite8(new, hd->base);
 55		break;
 56	}
 57}
 58
 59static void heartbeat_timer(struct timer_list *t)
 60{
 61	struct heartbeat_data *hd = from_timer(hd, t, timer);
 62	static unsigned bit = 0, up = 1;
 63
 64	heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
 65
 66	bit += up;
 67	if ((bit == 0) || (bit == (hd->nr_bits)-1))
 68		up = -up;
 69
 70	mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
 71			((avenrun[0] / 5) + (3 << FSHIFT)))));
 72}
 73
 74static int heartbeat_drv_probe(struct platform_device *pdev)
 75{
 76	struct resource *res;
 77	struct heartbeat_data *hd;
 78	int i;
 79
 80	if (unlikely(pdev->num_resources != 1)) {
 81		dev_err(&pdev->dev, "invalid number of resources\n");
 82		return -EINVAL;
 83	}
 84
 85	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 86	if (unlikely(res == NULL)) {
 87		dev_err(&pdev->dev, "invalid resource\n");
 88		return -EINVAL;
 89	}
 90
 91	if (pdev->dev.platform_data) {
 92		hd = pdev->dev.platform_data;
 93	} else {
 94		hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
 95		if (unlikely(!hd))
 96			return -ENOMEM;
 97	}
 98
 99	hd->base = ioremap(res->start, resource_size(res));
100	if (unlikely(!hd->base)) {
101		dev_err(&pdev->dev, "ioremap failed\n");
102
103		if (!pdev->dev.platform_data)
104			kfree(hd);
105
106		return -ENXIO;
107	}
108
109	if (!hd->nr_bits) {
110		hd->bit_pos = default_bit_pos;
111		hd->nr_bits = ARRAY_SIZE(default_bit_pos);
112	}
113
114	hd->mask = 0;
115	for (i = 0; i < hd->nr_bits; i++)
116		hd->mask |= (1 << hd->bit_pos[i]);
117
118	if (!hd->regsize) {
119		switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
120		case IORESOURCE_MEM_32BIT:
121			hd->regsize = 32;
122			break;
123		case IORESOURCE_MEM_16BIT:
124			hd->regsize = 16;
125			break;
126		case IORESOURCE_MEM_8BIT:
127		default:
128			hd->regsize = 8;
129			break;
130		}
131	}
132
133	timer_setup(&hd->timer, heartbeat_timer, 0);
134	platform_set_drvdata(pdev, hd);
135
136	return mod_timer(&hd->timer, jiffies + 1);
137}
138
139static struct platform_driver heartbeat_driver = {
140	.probe		= heartbeat_drv_probe,
141	.driver		= {
142		.name			= DRV_NAME,
143		.suppress_bind_attrs	= true,
144	},
145};
146
147static int __init heartbeat_init(void)
148{
149	printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
150	return platform_driver_register(&heartbeat_driver);
151}
152device_initcall(heartbeat_init);