xref: /linux/drivers/leds/leds-tlc591xx.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
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/of_device.h>
12 #include <linux/regmap.h>
13 #include <linux/slab.h>
14 
15 #define TLC591XX_MAX_LEDS	16
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 (brightness) {
116 	case 0:
117 		err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF);
118 		break;
119 	case LED_FULL:
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 void
132 tlc591xx_destroy_devices(struct tlc591xx_priv *priv, unsigned int j)
133 {
134 	int i = j;
135 
136 	while (--i >= 0) {
137 		if (priv->leds[i].active)
138 			led_classdev_unregister(&priv->leds[i].ldev);
139 	}
140 }
141 
142 static int
143 tlc591xx_configure(struct device *dev,
144 		   struct tlc591xx_priv *priv,
145 		   const struct tlc591xx *tlc591xx)
146 {
147 	unsigned int i;
148 	int err = 0;
149 
150 	tlc591xx_set_mode(priv->regmap, MODE2_DIM);
151 	for (i = 0; i < TLC591XX_MAX_LEDS; i++) {
152 		struct tlc591xx_led *led = &priv->leds[i];
153 
154 		if (!led->active)
155 			continue;
156 
157 		led->priv = priv;
158 		led->led_no = i;
159 		led->ldev.brightness_set_blocking = tlc591xx_brightness_set;
160 		led->ldev.max_brightness = LED_FULL;
161 		err = led_classdev_register(dev, &led->ldev);
162 		if (err < 0) {
163 			dev_err(dev, "couldn't register LED %s\n",
164 				led->ldev.name);
165 			goto exit;
166 		}
167 	}
168 
169 	return 0;
170 
171 exit:
172 	tlc591xx_destroy_devices(priv, i);
173 	return err;
174 }
175 
176 static const struct regmap_config tlc591xx_regmap = {
177 	.reg_bits = 8,
178 	.val_bits = 8,
179 	.max_register = 0x1e,
180 };
181 
182 static const struct of_device_id of_tlc591xx_leds_match[] = {
183 	{ .compatible = "ti,tlc59116",
184 	  .data = &tlc59116 },
185 	{ .compatible = "ti,tlc59108",
186 	  .data = &tlc59108 },
187 	{},
188 };
189 MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match);
190 
191 static int
192 tlc591xx_probe(struct i2c_client *client,
193 	       const struct i2c_device_id *id)
194 {
195 	struct device_node *np = client->dev.of_node, *child;
196 	struct device *dev = &client->dev;
197 	const struct of_device_id *match;
198 	const struct tlc591xx *tlc591xx;
199 	struct tlc591xx_priv *priv;
200 	int err, count, reg;
201 
202 	match = of_match_device(of_tlc591xx_leds_match, dev);
203 	if (!match)
204 		return -ENODEV;
205 
206 	tlc591xx = match->data;
207 	if (!np)
208 		return -ENODEV;
209 
210 	count = of_get_child_count(np);
211 	if (!count || count > tlc591xx->max_leds)
212 		return -EINVAL;
213 
214 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
215 	if (!priv)
216 		return -ENOMEM;
217 
218 	priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap);
219 	if (IS_ERR(priv->regmap)) {
220 		err = PTR_ERR(priv->regmap);
221 		dev_err(dev, "Failed to allocate register map: %d\n", err);
222 		return err;
223 	}
224 	priv->reg_ledout_offset = tlc591xx->reg_ledout_offset;
225 
226 	i2c_set_clientdata(client, priv);
227 
228 	for_each_child_of_node(np, child) {
229 		err = of_property_read_u32(child, "reg", &reg);
230 		if (err) {
231 			of_node_put(child);
232 			return err;
233 		}
234 		if (reg < 0 || reg >= tlc591xx->max_leds ||
235 		    priv->leds[reg].active) {
236 			of_node_put(child);
237 			return -EINVAL;
238 		}
239 		priv->leds[reg].active = true;
240 		priv->leds[reg].ldev.name =
241 			of_get_property(child, "label", NULL) ? : child->name;
242 		priv->leds[reg].ldev.default_trigger =
243 			of_get_property(child, "linux,default-trigger", NULL);
244 	}
245 	return tlc591xx_configure(dev, priv, tlc591xx);
246 }
247 
248 static int
249 tlc591xx_remove(struct i2c_client *client)
250 {
251 	struct tlc591xx_priv *priv = i2c_get_clientdata(client);
252 
253 	tlc591xx_destroy_devices(priv, TLC591XX_MAX_LEDS);
254 
255 	return 0;
256 }
257 
258 static const struct i2c_device_id tlc591xx_id[] = {
259 	{ "tlc59116" },
260 	{ "tlc59108" },
261 	{},
262 };
263 MODULE_DEVICE_TABLE(i2c, tlc591xx_id);
264 
265 static struct i2c_driver tlc591xx_driver = {
266 	.driver = {
267 		.name = "tlc591xx",
268 		.of_match_table = of_match_ptr(of_tlc591xx_leds_match),
269 	},
270 	.probe = tlc591xx_probe,
271 	.remove = tlc591xx_remove,
272 	.id_table = tlc591xx_id,
273 };
274 
275 module_i2c_driver(tlc591xx_driver);
276 
277 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
278 MODULE_LICENSE("GPL");
279 MODULE_DESCRIPTION("TLC591XX LED driver");
280