tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2016 National Instruments Corp.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/acpi.h>
16#include <linux/leds.h>
17#include <linux/module.h>
18#include <linux/platform_device.h>
19#include <linux/spinlock.h>
20
21#define NIC78BX_USER1_LED_MASK 0x3
22#define NIC78BX_USER1_GREEN_LED BIT(0)
23#define NIC78BX_USER1_YELLOW_LED BIT(1)
24
25#define NIC78BX_USER2_LED_MASK 0xC
26#define NIC78BX_USER2_GREEN_LED BIT(2)
27#define NIC78BX_USER2_YELLOW_LED BIT(3)
28
29#define NIC78BX_LOCK_REG_OFFSET 1
30#define NIC78BX_LOCK_VALUE 0xA5
31#define NIC78BX_UNLOCK_VALUE 0x5A
32
33#define NIC78BX_USER_LED_IO_SIZE 2
34
35struct nic78bx_led_data {
36 u16 io_base;
37 spinlock_t lock;
38 struct platform_device *pdev;
39};
40
41struct nic78bx_led {
42 u8 bit;
43 u8 mask;
44 struct nic78bx_led_data *data;
45 struct led_classdev cdev;
46};
47
48static inline struct nic78bx_led *to_nic78bx_led(struct led_classdev *cdev)
49{
50 return container_of(cdev, struct nic78bx_led, cdev);
51}
52
53static void nic78bx_brightness_set(struct led_classdev *cdev,
54 enum led_brightness brightness)
55{
56 struct nic78bx_led *nled = to_nic78bx_led(cdev);
57 unsigned long flags;
58 u8 value;
59
60 spin_lock_irqsave(&nled->data->lock, flags);
61 value = inb(nled->data->io_base);
62
63 if (brightness) {
64 value &= ~nled->mask;
65 value |= nled->bit;
66 } else {
67 value &= ~nled->bit;
68 }
69
70 outb(value, nled->data->io_base);
71 spin_unlock_irqrestore(&nled->data->lock, flags);
72}
73
74static enum led_brightness nic78bx_brightness_get(struct led_classdev *cdev)
75{
76 struct nic78bx_led *nled = to_nic78bx_led(cdev);
77 unsigned long flags;
78 u8 value;
79
80 spin_lock_irqsave(&nled->data->lock, flags);
81 value = inb(nled->data->io_base);
82 spin_unlock_irqrestore(&nled->data->lock, flags);
83
84 return (value & nled->bit) ? 1 : LED_OFF;
85}
86
87static struct nic78bx_led nic78bx_leds[] = {
88 {
89 .bit = NIC78BX_USER1_GREEN_LED,
90 .mask = NIC78BX_USER1_LED_MASK,
91 .cdev = {
92 .name = "nilrt:green:user1",
93 .max_brightness = 1,
94 .brightness_set = nic78bx_brightness_set,
95 .brightness_get = nic78bx_brightness_get,
96 }
97 },
98 {
99 .bit = NIC78BX_USER1_YELLOW_LED,
100 .mask = NIC78BX_USER1_LED_MASK,
101 .cdev = {
102 .name = "nilrt:yellow:user1",
103 .max_brightness = 1,
104 .brightness_set = nic78bx_brightness_set,
105 .brightness_get = nic78bx_brightness_get,
106 }
107 },
108 {
109 .bit = NIC78BX_USER2_GREEN_LED,
110 .mask = NIC78BX_USER2_LED_MASK,
111 .cdev = {
112 .name = "nilrt:green:user2",
113 .max_brightness = 1,
114 .brightness_set = nic78bx_brightness_set,
115 .brightness_get = nic78bx_brightness_get,
116 }
117 },
118 {
119 .bit = NIC78BX_USER2_YELLOW_LED,
120 .mask = NIC78BX_USER2_LED_MASK,
121 .cdev = {
122 .name = "nilrt:yellow:user2",
123 .max_brightness = 1,
124 .brightness_set = nic78bx_brightness_set,
125 .brightness_get = nic78bx_brightness_get,
126 }
127 }
128};
129
130static int nic78bx_probe(struct platform_device *pdev)
131{
132 struct device *dev = &pdev->dev;
133 struct nic78bx_led_data *led_data;
134 struct resource *io_rc;
135 int ret, i;
136
137 led_data = devm_kzalloc(dev, sizeof(*led_data), GFP_KERNEL);
138 if (!led_data)
139 return -ENOMEM;
140
141 led_data->pdev = pdev;
142 platform_set_drvdata(pdev, led_data);
143
144 io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
145 if (!io_rc) {
146 dev_err(dev, "missing IO resources\n");
147 return -EINVAL;
148 }
149
150 if (resource_size(io_rc) < NIC78BX_USER_LED_IO_SIZE) {
151 dev_err(dev, "IO region too small\n");
152 return -EINVAL;
153 }
154
155 if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
156 KBUILD_MODNAME)) {
157 dev_err(dev, "failed to get IO region\n");
158 return -EBUSY;
159 }
160
161 led_data->io_base = io_rc->start;
162 spin_lock_init(&led_data->lock);
163
164 for (i = 0; i < ARRAY_SIZE(nic78bx_leds); i++) {
165 nic78bx_leds[i].data = led_data;
166
167 ret = devm_led_classdev_register(dev, &nic78bx_leds[i].cdev);
168 if (ret)
169 return ret;
170 }
171
172 /* Unlock LED register */
173 outb(NIC78BX_UNLOCK_VALUE,
174 led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
175
176 return ret;
177}
178
179static int nic78bx_remove(struct platform_device *pdev)
180{
181 struct nic78bx_led_data *led_data = platform_get_drvdata(pdev);
182
183 /* Lock LED register */
184 outb(NIC78BX_LOCK_VALUE,
185 led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
186
187 return 0;
188}
189
190static const struct acpi_device_id led_device_ids[] = {
191 {"NIC78B3", 0},
192 {"", 0},
193};
194MODULE_DEVICE_TABLE(acpi, led_device_ids);
195
196static struct platform_driver led_driver = {
197 .probe = nic78bx_probe,
198 .remove = nic78bx_remove,
199 .driver = {
200 .name = KBUILD_MODNAME,
201 .acpi_match_table = ACPI_PTR(led_device_ids),
202 },
203};
204
205module_platform_driver(led_driver);
206
207MODULE_DESCRIPTION("National Instruments PXI User LEDs driver");
208MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
209MODULE_LICENSE("GPL");