1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2016 National Instruments Corp.
4 */
5
6 #include <linux/acpi.h>
7 #include <linux/leds.h>
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/spinlock.h>
11
12 #define NIC78BX_USER1_LED_MASK 0x3
13 #define NIC78BX_USER1_GREEN_LED BIT(0)
14 #define NIC78BX_USER1_YELLOW_LED BIT(1)
15
16 #define NIC78BX_USER2_LED_MASK 0xC
17 #define NIC78BX_USER2_GREEN_LED BIT(2)
18 #define NIC78BX_USER2_YELLOW_LED BIT(3)
19
20 #define NIC78BX_LOCK_REG_OFFSET 1
21 #define NIC78BX_LOCK_VALUE 0xA5
22 #define NIC78BX_UNLOCK_VALUE 0x5A
23
24 #define NIC78BX_USER_LED_IO_SIZE 2
25
26 struct nic78bx_led_data {
27 u16 io_base;
28 spinlock_t lock;
29 struct platform_device *pdev;
30 };
31
32 struct nic78bx_led {
33 u8 bit;
34 u8 mask;
35 struct nic78bx_led_data *data;
36 struct led_classdev cdev;
37 };
38
to_nic78bx_led(struct led_classdev * cdev)39 static inline struct nic78bx_led *to_nic78bx_led(struct led_classdev *cdev)
40 {
41 return container_of(cdev, struct nic78bx_led, cdev);
42 }
43
nic78bx_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)44 static void nic78bx_brightness_set(struct led_classdev *cdev,
45 enum led_brightness brightness)
46 {
47 struct nic78bx_led *nled = to_nic78bx_led(cdev);
48 unsigned long flags;
49 u8 value;
50
51 spin_lock_irqsave(&nled->data->lock, flags);
52 value = inb(nled->data->io_base);
53
54 if (brightness) {
55 value &= ~nled->mask;
56 value |= nled->bit;
57 } else {
58 value &= ~nled->bit;
59 }
60
61 outb(value, nled->data->io_base);
62 spin_unlock_irqrestore(&nled->data->lock, flags);
63 }
64
nic78bx_brightness_get(struct led_classdev * cdev)65 static enum led_brightness nic78bx_brightness_get(struct led_classdev *cdev)
66 {
67 struct nic78bx_led *nled = to_nic78bx_led(cdev);
68 unsigned long flags;
69 u8 value;
70
71 spin_lock_irqsave(&nled->data->lock, flags);
72 value = inb(nled->data->io_base);
73 spin_unlock_irqrestore(&nled->data->lock, flags);
74
75 return (value & nled->bit) ? 1 : LED_OFF;
76 }
77
78 static struct nic78bx_led nic78bx_leds[] = {
79 {
80 .bit = NIC78BX_USER1_GREEN_LED,
81 .mask = NIC78BX_USER1_LED_MASK,
82 .cdev = {
83 .name = "nilrt:green:user1",
84 .max_brightness = 1,
85 .brightness_set = nic78bx_brightness_set,
86 .brightness_get = nic78bx_brightness_get,
87 }
88 },
89 {
90 .bit = NIC78BX_USER1_YELLOW_LED,
91 .mask = NIC78BX_USER1_LED_MASK,
92 .cdev = {
93 .name = "nilrt:yellow:user1",
94 .max_brightness = 1,
95 .brightness_set = nic78bx_brightness_set,
96 .brightness_get = nic78bx_brightness_get,
97 }
98 },
99 {
100 .bit = NIC78BX_USER2_GREEN_LED,
101 .mask = NIC78BX_USER2_LED_MASK,
102 .cdev = {
103 .name = "nilrt:green:user2",
104 .max_brightness = 1,
105 .brightness_set = nic78bx_brightness_set,
106 .brightness_get = nic78bx_brightness_get,
107 }
108 },
109 {
110 .bit = NIC78BX_USER2_YELLOW_LED,
111 .mask = NIC78BX_USER2_LED_MASK,
112 .cdev = {
113 .name = "nilrt:yellow:user2",
114 .max_brightness = 1,
115 .brightness_set = nic78bx_brightness_set,
116 .brightness_get = nic78bx_brightness_get,
117 }
118 }
119 };
120
lock_led_reg_action(void * data)121 static void lock_led_reg_action(void *data)
122 {
123 struct nic78bx_led_data *led_data = data;
124
125 /* Lock LED register */
126 outb(NIC78BX_LOCK_VALUE,
127 led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
128 }
129
nic78bx_probe(struct platform_device * pdev)130 static 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 ret = devm_add_action(dev, lock_led_reg_action, led_data);
165 if (ret)
166 return ret;
167
168 for (i = 0; i < ARRAY_SIZE(nic78bx_leds); i++) {
169 nic78bx_leds[i].data = led_data;
170
171 ret = devm_led_classdev_register(dev, &nic78bx_leds[i].cdev);
172 if (ret)
173 return ret;
174 }
175
176 /* Unlock LED register */
177 outb(NIC78BX_UNLOCK_VALUE,
178 led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
179
180 return ret;
181 }
182
183 static const struct acpi_device_id led_device_ids[] = {
184 {"NIC78B3", 0},
185 {"", 0},
186 };
187 MODULE_DEVICE_TABLE(acpi, led_device_ids);
188
189 static struct platform_driver led_driver = {
190 .probe = nic78bx_probe,
191 .driver = {
192 .name = KBUILD_MODNAME,
193 .acpi_match_table = ACPI_PTR(led_device_ids),
194 },
195 };
196
197 module_platform_driver(led_driver);
198
199 MODULE_DESCRIPTION("National Instruments PXI User LEDs driver");
200 MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
201 MODULE_LICENSE("GPL");
202