aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-nic78bx.c
blob: f196f52eec1e2130177cd3d082ac37bd3c651e7b (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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2016 National Instruments Corp.
 */

#include <linux/acpi.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>

#define NIC78BX_USER1_LED_MASK		0x3
#define NIC78BX_USER1_GREEN_LED		BIT(0)
#define NIC78BX_USER1_YELLOW_LED	BIT(1)

#define NIC78BX_USER2_LED_MASK		0xC
#define NIC78BX_USER2_GREEN_LED		BIT(2)
#define NIC78BX_USER2_YELLOW_LED	BIT(3)

#define NIC78BX_LOCK_REG_OFFSET		1
#define NIC78BX_LOCK_VALUE		0xA5
#define NIC78BX_UNLOCK_VALUE		0x5A

#define NIC78BX_USER_LED_IO_SIZE	2

struct nic78bx_led_data {
	u16 io_base;
	spinlock_t lock;
	struct platform_device *pdev;
};

struct nic78bx_led {
	u8 bit;
	u8 mask;
	struct nic78bx_led_data *data;
	struct led_classdev cdev;
};

static inline struct nic78bx_led *to_nic78bx_led(struct led_classdev *cdev)
{
	return container_of(cdev, struct nic78bx_led, cdev);
}

static void nic78bx_brightness_set(struct led_classdev *cdev,
				  enum led_brightness brightness)
{
	struct nic78bx_led *nled = to_nic78bx_led(cdev);
	unsigned long flags;
	u8 value;

	spin_lock_irqsave(&nled->data->lock, flags);
	value = inb(nled->data->io_base);

	if (brightness) {
		value &= ~nled->mask;
		value |= nled->bit;
	} else {
		value &= ~nled->bit;
	}

	outb(value, nled->data->io_base);
	spin_unlock_irqrestore(&nled->data->lock, flags);
}

static enum led_brightness nic78bx_brightness_get(struct led_classdev *cdev)
{
	struct nic78bx_led *nled = to_nic78bx_led(cdev);
	unsigned long flags;
	u8 value;

	spin_lock_irqsave(&nled->data->lock, flags);
	value = inb(nled->data->io_base);
	spin_unlock_irqrestore(&nled->data->lock, flags);

	return (value & nled->bit) ? 1 : LED_OFF;
}

static struct nic78bx_led nic78bx_leds[] = {
	{
		.bit = NIC78BX_USER1_GREEN_LED,
		.mask = NIC78BX_USER1_LED_MASK,
		.cdev = {
			.name = "nilrt:green:user1",
			.max_brightness = 1,
			.brightness_set = nic78bx_brightness_set,
			.brightness_get = nic78bx_brightness_get,
		}
	},
	{
		.bit = NIC78BX_USER1_YELLOW_LED,
		.mask = NIC78BX_USER1_LED_MASK,
		.cdev = {
			.name = "nilrt:yellow:user1",
			.max_brightness = 1,
			.brightness_set = nic78bx_brightness_set,
			.brightness_get = nic78bx_brightness_get,
		}
	},
	{
		.bit = NIC78BX_USER2_GREEN_LED,
		.mask = NIC78BX_USER2_LED_MASK,
		.cdev = {
			.name = "nilrt:green:user2",
			.max_brightness = 1,
			.brightness_set = nic78bx_brightness_set,
			.brightness_get = nic78bx_brightness_get,
		}
	},
	{
		.bit = NIC78BX_USER2_YELLOW_LED,
		.mask = NIC78BX_USER2_LED_MASK,
		.cdev = {
			.name = "nilrt:yellow:user2",
			.max_brightness = 1,
			.brightness_set = nic78bx_brightness_set,
			.brightness_get = nic78bx_brightness_get,
		}
	}
};

static int nic78bx_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct nic78bx_led_data *led_data;
	struct resource *io_rc;
	int ret, i;

	led_data = devm_kzalloc(dev, sizeof(*led_data), GFP_KERNEL);
	if (!led_data)
		return -ENOMEM;

	led_data->pdev = pdev;
	platform_set_drvdata(pdev, led_data);

	io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
	if (!io_rc) {
		dev_err(dev, "missing IO resources\n");
		return -EINVAL;
	}

	if (resource_size(io_rc) < NIC78BX_USER_LED_IO_SIZE) {
		dev_err(dev, "IO region too small\n");
		return -EINVAL;
	}

	if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
				 KBUILD_MODNAME)) {
		dev_err(dev, "failed to get IO region\n");
		return -EBUSY;
	}

	led_data->io_base = io_rc->start;
	spin_lock_init(&led_data->lock);

	for (i = 0; i < ARRAY_SIZE(nic78bx_leds); i++) {
		nic78bx_leds[i].data = led_data;

		ret = devm_led_classdev_register(dev, &nic78bx_leds[i].cdev);
		if (ret)
			return ret;
	}

	/* Unlock LED register */
	outb(NIC78BX_UNLOCK_VALUE,
	     led_data->io_base + NIC78BX_LOCK_REG_OFFSET);

	return ret;
}

static int nic78bx_remove(struct platform_device *pdev)
{
	struct nic78bx_led_data *led_data = platform_get_drvdata(pdev);

	/* Lock LED register */
	outb(NIC78BX_LOCK_VALUE,
	     led_data->io_base + NIC78BX_LOCK_REG_OFFSET);

	return 0;
}

static const struct acpi_device_id led_device_ids[] = {
	{"NIC78B3", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, led_device_ids);

static struct platform_driver led_driver = {
	.probe = nic78bx_probe,
	.remove = nic78bx_remove,
	.driver = {
		.name = KBUILD_MODNAME,
		.acpi_match_table = ACPI_PTR(led_device_ids),
	},
};

module_platform_driver(led_driver);

MODULE_DESCRIPTION("National Instruments PXI User LEDs driver");
MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
MODULE_LICENSE("GPL");