xref: /linux/drivers/leds/leds-tlc591xx.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2014 Belkin Inc.
4  * Copyright 2015 Andrew Lunn <andrew@lunn.ch>
5  */
6 
7 #include <linux/i2c.h>
8 #include <linux/leds.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/regmap.h>
12 #include <linux/slab.h>
13 
14 #define TLC591XX_MAX_LEDS	16
15 #define TLC591XX_MAX_BRIGHTNESS	256
16 
17 #define TLC591XX_REG_MODE1	0x00
18 #define MODE1_RESPON_ADDR_MASK	0xF0
19 #define MODE1_NORMAL_MODE	(0 << 4)
20 #define MODE1_SPEED_MODE	(1 << 4)
21 
22 #define TLC591XX_REG_MODE2	0x01
23 #define MODE2_DIM		(0 << 5)
24 #define MODE2_BLINK		(1 << 5)
25 #define MODE2_OCH_STOP		(0 << 3)
26 #define MODE2_OCH_ACK		(1 << 3)
27 
28 #define TLC591XX_REG_PWM(x)	(0x02 + (x))
29 
30 #define TLC591XX_REG_GRPPWM	0x12
31 #define TLC591XX_REG_GRPFREQ	0x13
32 
33 /* LED Driver Output State, determine the source that drives LED outputs */
34 #define LEDOUT_OFF		0x0	/* Output LOW */
35 #define LEDOUT_ON		0x1	/* Output HI-Z */
36 #define LEDOUT_DIM		0x2	/* Dimming */
37 #define LEDOUT_BLINK		0x3	/* Blinking */
38 #define LEDOUT_MASK		0x3
39 
40 #define ldev_to_led(c)		container_of(c, struct tlc591xx_led, ldev)
41 
42 struct tlc591xx_led {
43 	bool active;
44 	unsigned int led_no;
45 	struct led_classdev ldev;
46 	struct tlc591xx_priv *priv;
47 };
48 
49 struct tlc591xx_priv {
50 	struct tlc591xx_led leds[TLC591XX_MAX_LEDS];
51 	struct regmap *regmap;
52 	unsigned int reg_ledout_offset;
53 };
54 
55 struct tlc591xx {
56 	unsigned int max_leds;
57 	unsigned int reg_ledout_offset;
58 };
59 
60 static const struct tlc591xx tlc59116 = {
61 	.max_leds = 16,
62 	.reg_ledout_offset = 0x14,
63 };
64 
65 static const struct tlc591xx tlc59108 = {
66 	.max_leds = 8,
67 	.reg_ledout_offset = 0x0c,
68 };
69 
70 static int
71 tlc591xx_set_mode(struct regmap *regmap, u8 mode)
72 {
73 	int err;
74 	u8 val;
75 
76 	err = regmap_write(regmap, TLC591XX_REG_MODE1, MODE1_NORMAL_MODE);
77 	if (err)
78 		return err;
79 
80 	val = MODE2_OCH_STOP | mode;
81 
82 	return regmap_write(regmap, TLC591XX_REG_MODE2, val);
83 }
84 
85 static int
86 tlc591xx_set_ledout(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
87 		    u8 val)
88 {
89 	unsigned int i = (led->led_no % 4) * 2;
90 	unsigned int mask = LEDOUT_MASK << i;
91 	unsigned int addr = priv->reg_ledout_offset + (led->led_no >> 2);
92 
93 	val = val << i;
94 
95 	return regmap_update_bits(priv->regmap, addr, mask, val);
96 }
97 
98 static int
99 tlc591xx_set_pwm(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
100 		 u8 brightness)
101 {
102 	u8 pwm = TLC591XX_REG_PWM(led->led_no);
103 
104 	return regmap_write(priv->regmap, pwm, brightness);
105 }
106 
107 static int
108 tlc591xx_brightness_set(struct led_classdev *led_cdev,
109 			enum led_brightness brightness)
110 {
111 	struct tlc591xx_led *led = ldev_to_led(led_cdev);
112 	struct tlc591xx_priv *priv = led->priv;
113 	int err;
114 
115 	switch ((int)brightness) {
116 	case 0:
117 		err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF);
118 		break;
119 	case TLC591XX_MAX_BRIGHTNESS:
120 		err = tlc591xx_set_ledout(priv, led, LEDOUT_ON);
121 		break;
122 	default:
123 		err = tlc591xx_set_ledout(priv, led, LEDOUT_DIM);
124 		if (!err)
125 			err = tlc591xx_set_pwm(priv, led, brightness);
126 	}
127 
128 	return err;
129 }
130 
131 static const struct regmap_config tlc591xx_regmap = {
132 	.reg_bits = 8,
133 	.val_bits = 8,
134 	.max_register = 0x1e,
135 };
136 
137 static const struct of_device_id of_tlc591xx_leds_match[] __maybe_unused = {
138 	{ .compatible = "ti,tlc59116",
139 	  .data = &tlc59116 },
140 	{ .compatible = "ti,tlc59108",
141 	  .data = &tlc59108 },
142 	{},
143 };
144 MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match);
145 
146 static int
147 tlc591xx_probe(struct i2c_client *client)
148 {
149 	struct device_node *np, *child;
150 	struct device *dev = &client->dev;
151 	const struct tlc591xx *tlc591xx;
152 	struct tlc591xx_priv *priv;
153 	int err, count, reg;
154 
155 	np = dev_of_node(dev);
156 	if (!np)
157 		return -ENODEV;
158 
159 	tlc591xx = device_get_match_data(dev);
160 	if (!tlc591xx)
161 		return -ENODEV;
162 
163 	count = of_get_available_child_count(np);
164 	if (!count || count > tlc591xx->max_leds)
165 		return -EINVAL;
166 
167 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
168 	if (!priv)
169 		return -ENOMEM;
170 
171 	priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap);
172 	if (IS_ERR(priv->regmap)) {
173 		err = PTR_ERR(priv->regmap);
174 		dev_err(dev, "Failed to allocate register map: %d\n", err);
175 		return err;
176 	}
177 	priv->reg_ledout_offset = tlc591xx->reg_ledout_offset;
178 
179 	i2c_set_clientdata(client, priv);
180 
181 	err = tlc591xx_set_mode(priv->regmap, MODE2_DIM);
182 	if (err < 0)
183 		return err;
184 
185 	for_each_available_child_of_node(np, child) {
186 		struct tlc591xx_led *led;
187 		struct led_init_data init_data = {};
188 
189 		init_data.fwnode = of_fwnode_handle(child);
190 
191 		err = of_property_read_u32(child, "reg", &reg);
192 		if (err) {
193 			of_node_put(child);
194 			return err;
195 		}
196 		if (reg < 0 || reg >= tlc591xx->max_leds ||
197 		    priv->leds[reg].active) {
198 			of_node_put(child);
199 			return -EINVAL;
200 		}
201 		led = &priv->leds[reg];
202 
203 		led->active = true;
204 		led->priv = priv;
205 		led->led_no = reg;
206 		led->ldev.brightness_set_blocking = tlc591xx_brightness_set;
207 		led->ldev.max_brightness = TLC591XX_MAX_BRIGHTNESS;
208 		err = devm_led_classdev_register_ext(dev, &led->ldev,
209 						     &init_data);
210 		if (err < 0) {
211 			of_node_put(child);
212 			return dev_err_probe(dev, err,
213 					     "couldn't register LED %s\n",
214 					     led->ldev.name);
215 		}
216 	}
217 	return 0;
218 }
219 
220 static const struct i2c_device_id tlc591xx_id[] = {
221 	{ "tlc59116" },
222 	{ "tlc59108" },
223 	{},
224 };
225 MODULE_DEVICE_TABLE(i2c, tlc591xx_id);
226 
227 static struct i2c_driver tlc591xx_driver = {
228 	.driver = {
229 		.name = "tlc591xx",
230 		.of_match_table = of_match_ptr(of_tlc591xx_leds_match),
231 	},
232 	.probe = tlc591xx_probe,
233 	.id_table = tlc591xx_id,
234 };
235 
236 module_i2c_driver(tlc591xx_driver);
237 
238 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
239 MODULE_LICENSE("GPL");
240 MODULE_DESCRIPTION("TLC591XX LED driver");
241