summaryrefslogtreecommitdiff
path: root/arch/arm/plat-omap/debug-leds.c
blob: 2b698d074874529c9d8a2766efd62ec384574577 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/arch/arm/plat-omap/debug-leds.c
 *
 * Copyright 2011 by Bryan Wu <bryan.wu@canonical.com>
 * Copyright 2003 by Texas Instruments Incorporated
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/io.h>
#include <linux/platform_data/gpio-omap.h>
#include <linux/slab.h>

#include <asm/mach-types.h>

/* Many OMAP development platforms reuse the same "debug board"; these
 * platforms include H2, H3, H4, and Perseus2.  There are 16 LEDs on the
 * debug board (all green), accessed through FPGA registers.
 */

/* NOTE:  most boards don't have a static mapping for the FPGA ... */
struct h2p2_dbg_fpga {
	/* offset 0x00 */
	u16		smc91x[8];
	/* offset 0x10 */
	u16		fpga_rev;
	u16		board_rev;
	u16		gpio_outputs;
	u16		leds;
	/* offset 0x18 */
	u16		misc_inputs;
	u16		lan_status;
	u16		lan_reset;
	u16		reserved0;
	/* offset 0x20 */
	u16		ps2_data;
	u16		ps2_ctrl;
	/* plus also 4 rs232 ports ... */
};

static struct h2p2_dbg_fpga __iomem *fpga;

static u16 fpga_led_state;

struct dbg_led {
	struct led_classdev	cdev;
	u16			mask;
};

static const struct {
	const char *name;
	const char *trigger;
} dbg_leds[] = {
	{ "dbg:d4", "heartbeat", },
	{ "dbg:d5", "cpu0", },
	{ "dbg:d6", "default-on", },
	{ "dbg:d7", },
	{ "dbg:d8", },
	{ "dbg:d9", },
	{ "dbg:d10", },
	{ "dbg:d11", },
	{ "dbg:d12", },
	{ "dbg:d13", },
	{ "dbg:d14", },
	{ "dbg:d15", },
	{ "dbg:d16", },
	{ "dbg:d17", },
	{ "dbg:d18", },
	{ "dbg:d19", },
};

/*
 * The triggers lines up below will only be used if the
 * LED triggers are compiled in.
 */
static void dbg_led_set(struct led_classdev *cdev,
			      enum led_brightness b)
{
	struct dbg_led *led = container_of(cdev, struct dbg_led, cdev);
	u16 reg;

	reg = readw_relaxed(&fpga->leds);
	if (b != LED_OFF)
		reg |= led->mask;
	else
		reg &= ~led->mask;
	writew_relaxed(reg, &fpga->leds);
}

static enum led_brightness dbg_led_get(struct led_classdev *cdev)
{
	struct dbg_led *led = container_of(cdev, struct dbg_led, cdev);
	u16 reg;

	reg = readw_relaxed(&fpga->leds);
	return (reg & led->mask) ? LED_FULL : LED_OFF;
}

static int fpga_probe(struct platform_device *pdev)
{
	struct resource	*iomem;
	int i;

	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!iomem)
		return -ENODEV;

	fpga = ioremap(iomem->start, resource_size(iomem));
	writew_relaxed(0xff, &fpga->leds);

	for (i = 0; i < ARRAY_SIZE(dbg_leds); i++) {
		struct dbg_led *led;

		led = kzalloc(sizeof(*led), GFP_KERNEL);
		if (!led)
			break;

		led->cdev.name = dbg_leds[i].name;
		led->cdev.brightness_set = dbg_led_set;
		led->cdev.brightness_get = dbg_led_get;
		led->cdev.default_trigger = dbg_leds[i].trigger;
		led->mask = BIT(i);

		if (led_classdev_register(NULL, &led->cdev) < 0) {
			kfree(led);
			break;
		}
	}

	return 0;
}

static int fpga_suspend_noirq(struct device *dev)
{
	fpga_led_state = readw_relaxed(&fpga->leds);
	writew_relaxed(0xff, &fpga->leds);

	return 0;
}

static int fpga_resume_noirq(struct device *dev)
{
	writew_relaxed(~fpga_led_state, &fpga->leds);
	return 0;
}

static const struct dev_pm_ops fpga_dev_pm_ops = {
	.suspend_noirq = fpga_suspend_noirq,
	.resume_noirq = fpga_resume_noirq,
};

static struct platform_driver led_driver = {
	.driver.name	= "omap_dbg_led",
	.driver.pm	= &fpga_dev_pm_ops,
	.probe		= fpga_probe,
};

static int __init fpga_init(void)
{
	if (machine_is_omap_h4()
			|| machine_is_omap_h3()
			|| machine_is_omap_h2()
			|| machine_is_omap_perseus2()
			)
		return platform_driver_register(&led_driver);
	return 0;
}
fs_initcall(fpga_init);