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
tlc591xx_set_mode(struct regmap * regmap,u8 mode)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
tlc591xx_set_ledout(struct tlc591xx_priv * priv,struct tlc591xx_led * led,u8 val)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
tlc591xx_set_pwm(struct tlc591xx_priv * priv,struct tlc591xx_led * led,u8 brightness)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
tlc591xx_brightness_set(struct led_classdev * led_cdev,enum led_brightness brightness)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
tlc591xx_probe(struct i2c_client * client)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", ®);
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