aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/files/drivers/leds/leds-ubnt-ledbar.c
blob: 555340c5e87fd211b80dbf3a1a62b348bb25b940 (plain)
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
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
// SPDX-License-Identifier: GPL-2.0-only

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/gpio/consumer.h>

/**
 * Driver for the Ubiquiti RGB LED controller (LEDBAR).
 * This Controller is based on a Holtek HT32F52241 and connected
 * via I2C.
 *
 *  - The Controller needs an enable signal set to high when
 *    performing a transaction. On the U6-LR, this is located
 *    at Pin 18 (R6902)
 *
 *  - The Pin is also printed when calling the "usetled" function
 *    contained in the ubntapp bootloader application.
 */

#define UBNT_LEDBAR_MAX_BRIGHTNESS	0xff

#define UBNT_LEDBAR_TRANSACTION_LENGTH	8
#define UBNT_LEDBAR_TRANSACTION_SUCCESS	(char) 0xaa

#define UBNT_LEDBAR_TRANSACTION_BLUE_IDX	2
#define UBNT_LEDBAR_TRANSACTION_GREEN_IDX	3
#define UBNT_LEDBAR_TRANSACTION_RED_IDX		4
#define UBNT_LEDBAR_TRANSACTION_LED_COUNT_IDX	6

struct ubnt_ledbar {
	struct mutex lock;
	u32 led_count;
	struct i2c_client *client;
	struct led_classdev led_red;
	struct led_classdev led_green;
	struct led_classdev led_blue;
	struct gpio_desc *enable_gpio;
	struct gpio_desc *reset_gpio;
};

static void ubnt_ledbar_perform_transaction(struct ubnt_ledbar *ledbar,
					   const char *transaction, int len,
					   char *result, int result_len)
{
	int i;

	for (i = 0; i < len; i++)
		i2c_smbus_write_byte(ledbar->client, transaction[i]);

	for (i = 0; i < result_len; i++)
		result[i] = i2c_smbus_read_byte(ledbar->client);
}

static int ubnt_ledbar_apply_state(struct ubnt_ledbar *ledbar)
{
	char setup_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x10, 0x00, 0x00,
							  0x00, 0x00, 0x00, 0x11};
	char led_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x00, 0x00, 0x00,
							0x00, 0x00, 0x00, 0x00};
	char i2c_response;
	int ret = 0;

	mutex_lock(&ledbar->lock);

	led_msg[UBNT_LEDBAR_TRANSACTION_BLUE_IDX] = ledbar->led_blue.brightness;
	led_msg[UBNT_LEDBAR_TRANSACTION_GREEN_IDX] = ledbar->led_green.brightness;
	led_msg[UBNT_LEDBAR_TRANSACTION_RED_IDX] = ledbar->led_red.brightness;
	led_msg[UBNT_LEDBAR_TRANSACTION_LED_COUNT_IDX] = ledbar->led_count;

	gpiod_set_value(ledbar->enable_gpio, 1);

	msleep(10);

	ubnt_ledbar_perform_transaction(ledbar, setup_msg, sizeof(setup_msg), &i2c_response, sizeof(i2c_response));
	if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
		dev_err(&ledbar->client->dev, "Error initializing LED transaction: %02hhx\n", i2c_response);
		ret = -EINVAL;
		goto out_gpio;
	}

	ubnt_ledbar_perform_transaction(ledbar, led_msg, sizeof(led_msg), &i2c_response, sizeof(i2c_response));
	if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
		dev_err(&ledbar->client->dev, "Failed LED transaction: %02hhx\n", i2c_response);
		ret = -EINVAL;
		goto out_gpio;
	}

	msleep(10);
out_gpio:
	gpiod_set_value(ledbar->enable_gpio, 0);

	mutex_unlock(&ledbar->lock);

	return ret;
}

static void ubnt_ledbar_reset(struct ubnt_ledbar *ledbar)
{
	static const char init_msg[16] = {0x02, 0x81, 0xfd, 0x7e,
					  0x00, 0x00, 0x00, 0x00,
					  0x00, 0x00, 0x00, 0x00,
					  0x00, 0x00, 0x00, 0x00};
	char init_response[4];

	if (!ledbar->reset_gpio)
		return;

	mutex_lock(&ledbar->lock);

	gpiod_set_value(ledbar->reset_gpio, 1);
	msleep(10);
	gpiod_set_value(ledbar->reset_gpio, 0);

	msleep(10);

	gpiod_set_value(ledbar->enable_gpio, 1);
	msleep(10);
	ubnt_ledbar_perform_transaction(ledbar, init_msg, sizeof(init_msg), init_response, sizeof(init_response));
	msleep(10);
	gpiod_set_value(ledbar->enable_gpio, 0);

	mutex_unlock(&ledbar->lock);
}

#define UBNT_LEDBAR_CONTROL_RGBS(name)				\
static int ubnt_ledbar_set_##name##_brightness(struct led_classdev *led_cdev,\
					enum led_brightness value)	\
{									\
	struct ubnt_ledbar *ledbar = \
			container_of(led_cdev, struct ubnt_ledbar, led_##name); \
	int ret; \
	led_cdev->brightness = value; \
	ret = ubnt_ledbar_apply_state(ledbar); \
	return ret; \
}

UBNT_LEDBAR_CONTROL_RGBS(red);
UBNT_LEDBAR_CONTROL_RGBS(green);
UBNT_LEDBAR_CONTROL_RGBS(blue);


static int ubnt_ledbar_init_led(struct device_node *np, struct ubnt_ledbar *ledbar,
				struct led_classdev *led_cdev)
{
	struct led_init_data init_data = {};
	int ret;

	if (!np)
		return 0;

	init_data.fwnode = of_fwnode_handle(np);

	led_cdev->max_brightness = UBNT_LEDBAR_MAX_BRIGHTNESS;

	ret = devm_led_classdev_register_ext(&ledbar->client->dev, led_cdev,
					     &init_data);
	if (ret)
		dev_err(&ledbar->client->dev, "led register err: %d\n", ret);

	return ret;
}


static int ubnt_ledbar_probe(struct i2c_client *client,
			     const struct i2c_device_id *id)
{
	struct device_node *np = client->dev.of_node;
	struct ubnt_ledbar *ledbar;
	int ret;

	ledbar = devm_kzalloc(&client->dev, sizeof(*ledbar), GFP_KERNEL);
	if (!ledbar)
		return -ENOMEM;

	ledbar->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);

	if (IS_ERR(ledbar->enable_gpio)) {
		ret = PTR_ERR(ledbar->enable_gpio);
		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
		return ret;
	}

	ledbar->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW);

	if (IS_ERR(ledbar->reset_gpio)) {
		ret = PTR_ERR(ledbar->reset_gpio);
		dev_err(&client->dev, "Failed to get reset gpio: %d\n", ret);
		return ret;
	}

	ledbar->led_count = 1;
	of_property_read_u32(np, "led-count", &ledbar->led_count);

	ledbar->client = client;

	mutex_init(&ledbar->lock);

	i2c_set_clientdata(client, ledbar);

	// Reset and initialize the MCU
	ubnt_ledbar_reset(ledbar);

	ledbar->led_red.brightness_set_blocking = ubnt_ledbar_set_red_brightness;
	ubnt_ledbar_init_led(of_get_child_by_name(np, "red"), ledbar, &ledbar->led_red);

	ledbar->led_green.brightness_set_blocking = ubnt_ledbar_set_green_brightness;
	ubnt_ledbar_init_led(of_get_child_by_name(np, "green"), ledbar, &ledbar->led_green);

	ledbar->led_blue.brightness_set_blocking = ubnt_ledbar_set_blue_brightness;
	ubnt_ledbar_init_led(of_get_child_by_name(np, "blue"), ledbar, &ledbar->led_blue);

	return ubnt_ledbar_apply_state(ledbar);
}

static int ubnt_ledbar_remove(struct i2c_client *client)
{
	struct ubnt_ledbar *ledbar = i2c_get_clientdata(client);

	mutex_destroy(&ledbar->lock);

	return 0;
}

static const struct i2c_device_id ubnt_ledbar_id[] = {
	{ "ubnt-ledbar", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, ubnt_ledbar_id);

static const struct of_device_id of_ubnt_ledbar_match[] = {
	{ .compatible = "ubnt,ledbar", },
	{},
};
MODULE_DEVICE_TABLE(of, of_ubnt_ledbar_match);

static struct i2c_driver ubnt_ledbar_driver = {
	.driver = {
		.name	= "ubnt-ledbar",
		.of_match_table = of_ubnt_ledbar_match,
	},
	.probe		= ubnt_ledbar_probe,
	.remove		= ubnt_ledbar_remove,
	.id_table	= ubnt_ledbar_id,
};
module_i2c_driver(ubnt_ledbar_driver);

MODULE_DESCRIPTION("Ubiquiti LEDBAR driver");
MODULE_AUTHOR("David Bauer <mail@david-bauer.net>");
MODULE_LICENSE("GPL v2");