xref: /linux/drivers/leds/leds-upboard.c (revision 11a7b03346e2ac4bf13783d409dd7ec0ecf1f3ac)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * UP board LED driver.
4  *
5  * Copyright (c) AAEON. All rights reserved.
6  * Copyright (C) 2024 Bootlin
7  *
8  * Author: Gary Wang <garywang@aaeon.com.tw>
9  * Author: Thomas Richard <thomas.richard@bootlin.com>
10  */
11 
12 #include <linux/device.h>
13 #include <linux/container_of.h>
14 #include <linux/leds.h>
15 #include <linux/mfd/upboard-fpga.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/regmap.h>
19 
20 #define led_cdev_to_led_upboard(c)	container_of(c, struct upboard_led, cdev)
21 
22 struct upboard_led {
23 	struct regmap_field *field;
24 	struct led_classdev cdev;
25 };
26 
27 struct upboard_led_profile {
28 	const char *name;
29 	unsigned int bit;
30 };
31 
32 static struct upboard_led_profile upboard_up_led_profile[] = {
33 	{ "upboard:yellow:" LED_FUNCTION_STATUS, 0 },
34 	{ "upboard:green:" LED_FUNCTION_STATUS, 1 },
35 	{ "upboard:red:" LED_FUNCTION_STATUS, 2 },
36 };
37 
38 static struct upboard_led_profile upboard_up2_led_profile[] = {
39 	{ "upboard:blue:" LED_FUNCTION_STATUS, 0 },
40 	{ "upboard:yellow:" LED_FUNCTION_STATUS, 1 },
41 	{ "upboard:green:" LED_FUNCTION_STATUS, 2 },
42 	{ "upboard:red:" LED_FUNCTION_STATUS, 3 },
43 };
44 
45 static enum led_brightness upboard_led_brightness_get(struct led_classdev *cdev)
46 {
47 	struct upboard_led *led = led_cdev_to_led_upboard(cdev);
48 	int brightness, ret;
49 
50 	ret = regmap_field_read(led->field, &brightness);
51 
52 	return ret ? LED_OFF : brightness;
53 };
54 
55 static int upboard_led_brightness_set(struct led_classdev *cdev, enum led_brightness brightness)
56 {
57 	struct upboard_led *led = led_cdev_to_led_upboard(cdev);
58 
59 	return regmap_field_write(led->field, brightness != LED_OFF);
60 };
61 
62 static int upboard_led_probe(struct platform_device *pdev)
63 {
64 	struct device *dev = &pdev->dev;
65 	struct upboard_fpga *fpga = dev_get_drvdata(dev->parent);
66 	struct upboard_led_profile *led_profile;
67 	struct upboard_led *led;
68 	int led_instances, ret, i;
69 
70 	switch (fpga->fpga_data->type) {
71 	case UPBOARD_UP_FPGA:
72 		led_profile = upboard_up_led_profile;
73 		led_instances = ARRAY_SIZE(upboard_up_led_profile);
74 		break;
75 	case UPBOARD_UP2_FPGA:
76 		led_profile = upboard_up2_led_profile;
77 		led_instances = ARRAY_SIZE(upboard_up2_led_profile);
78 		break;
79 	default:
80 		return dev_err_probe(dev, -EINVAL, "Unknown device type %d\n",
81 				     fpga->fpga_data->type);
82 	}
83 
84 	for (i = 0; i < led_instances; i++) {
85 		const struct reg_field fldconf = {
86 			.reg = UPBOARD_REG_FUNC_EN0,
87 			.lsb = led_profile[i].bit,
88 			.msb = led_profile[i].bit,
89 		};
90 
91 		led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
92 		if (!led)
93 			return -ENOMEM;
94 
95 		led->field = devm_regmap_field_alloc(&pdev->dev, fpga->regmap, fldconf);
96 		if (IS_ERR(led->field))
97 			return PTR_ERR(led->field);
98 
99 		led->cdev.brightness_get = upboard_led_brightness_get;
100 		led->cdev.brightness_set_blocking = upboard_led_brightness_set;
101 		led->cdev.max_brightness = LED_ON;
102 
103 		led->cdev.name = led_profile[i].name;
104 
105 		ret = devm_led_classdev_register(dev, &led->cdev);
106 		if (ret)
107 			return ret;
108 	}
109 
110 	return 0;
111 }
112 
113 static struct platform_driver upboard_led_driver = {
114 	.driver = {
115 		.name = "upboard-leds",
116 	},
117 	.probe = upboard_led_probe,
118 };
119 
120 module_platform_driver(upboard_led_driver);
121 
122 MODULE_AUTHOR("Gary Wang <garywang@aaeon.com.tw>");
123 MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>");
124 MODULE_DESCRIPTION("UP Board LED driver");
125 MODULE_LICENSE("GPL");
126 MODULE_ALIAS("platform:upboard-led");
127