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#define TLC591XX_MAX_BRIGHTNESS	256
17
18#define TLC591XX_REG_MODE1	0x00
19#define MODE1_RESPON_ADDR_MASK	0xF0
20#define MODE1_NORMAL_MODE	(0 << 4)
21#define MODE1_SPEED_MODE	(1 << 4)
22
23#define TLC591XX_REG_MODE2	0x01
24#define MODE2_DIM		(0 << 5)
25#define MODE2_BLINK		(1 << 5)
26#define MODE2_OCH_STOP		(0 << 3)
27#define MODE2_OCH_ACK		(1 << 3)
28
29#define TLC591XX_REG_PWM(x)	(0x02 + (x))
30
31#define TLC591XX_REG_GRPPWM	0x12
32#define TLC591XX_REG_GRPFREQ	0x13
33
34/* LED Driver Output State, determine the source that drives LED outputs */
35#define LEDOUT_OFF		0x0	/* Output LOW */
36#define LEDOUT_ON		0x1	/* Output HI-Z */
37#define LEDOUT_DIM		0x2	/* Dimming */
38#define LEDOUT_BLINK		0x3	/* Blinking */
39#define LEDOUT_MASK		0x3
40
41#define ldev_to_led(c)		container_of(c, struct tlc591xx_led, ldev)
42
43struct tlc591xx_led {
44	bool active;
45	unsigned int led_no;
46	struct led_classdev ldev;
47	struct tlc591xx_priv *priv;
48};
49
50struct tlc591xx_priv {
51	struct tlc591xx_led leds[TLC591XX_MAX_LEDS];
52	struct regmap *regmap;
53	unsigned int reg_ledout_offset;
54};
55
56struct tlc591xx {
57	unsigned int max_leds;
58	unsigned int reg_ledout_offset;
59};
60
61static const struct tlc591xx tlc59116 = {
62	.max_leds = 16,
63	.reg_ledout_offset = 0x14,
64};
65
66static const struct tlc591xx tlc59108 = {
67	.max_leds = 8,
68	.reg_ledout_offset = 0x0c,
69};
70
71static int
72tlc591xx_set_mode(struct regmap *regmap, u8 mode)
73{
74	int err;
75	u8 val;
76
77	err = regmap_write(regmap, TLC591XX_REG_MODE1, MODE1_NORMAL_MODE);
78	if (err)
79		return err;
80
81	val = MODE2_OCH_STOP | mode;
82
83	return regmap_write(regmap, TLC591XX_REG_MODE2, val);
84}
85
86static int
87tlc591xx_set_ledout(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
88		    u8 val)
89{
90	unsigned int i = (led->led_no % 4) * 2;
91	unsigned int mask = LEDOUT_MASK << i;
92	unsigned int addr = priv->reg_ledout_offset + (led->led_no >> 2);
93
94	val = val << i;
95
96	return regmap_update_bits(priv->regmap, addr, mask, val);
97}
98
99static int
100tlc591xx_set_pwm(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
101		 u8 brightness)
102{
103	u8 pwm = TLC591XX_REG_PWM(led->led_no);
104
105	return regmap_write(priv->regmap, pwm, brightness);
106}
107
108static int
109tlc591xx_brightness_set(struct led_classdev *led_cdev,
110			enum led_brightness brightness)
111{
112	struct tlc591xx_led *led = ldev_to_led(led_cdev);
113	struct tlc591xx_priv *priv = led->priv;
114	int err;
115
116	switch ((int)brightness) {
117	case 0:
118		err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF);
119		break;
120	case TLC591XX_MAX_BRIGHTNESS:
121		err = tlc591xx_set_ledout(priv, led, LEDOUT_ON);
122		break;
123	default:
124		err = tlc591xx_set_ledout(priv, led, LEDOUT_DIM);
125		if (!err)
126			err = tlc591xx_set_pwm(priv, led, brightness);
127	}
128
129	return err;
130}
131
132static const struct regmap_config tlc591xx_regmap = {
133	.reg_bits = 8,
134	.val_bits = 8,
135	.max_register = 0x1e,
136};
137
138static const struct of_device_id of_tlc591xx_leds_match[] = {
139	{ .compatible = "ti,tlc59116",
140	  .data = &tlc59116 },
141	{ .compatible = "ti,tlc59108",
142	  .data = &tlc59108 },
143	{},
144};
145MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match);
146
147static int
148tlc591xx_probe(struct i2c_client *client,
149	       const struct i2c_device_id *id)
150{
151	struct device_node *np, *child;
152	struct device *dev = &client->dev;
153	const struct tlc591xx *tlc591xx;
154	struct tlc591xx_priv *priv;
155	int err, count, reg;
156
157	np = dev_of_node(dev);
158	if (!np)
159		return -ENODEV;
160
161	tlc591xx = device_get_match_data(dev);
162	if (!tlc591xx)
163		return -ENODEV;
164
165	count = of_get_available_child_count(np);
166	if (!count || count > tlc591xx->max_leds)
167		return -EINVAL;
168
169	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
170	if (!priv)
171		return -ENOMEM;
172
173	priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap);
174	if (IS_ERR(priv->regmap)) {
175		err = PTR_ERR(priv->regmap);
176		dev_err(dev, "Failed to allocate register map: %d\n", err);
177		return err;
178	}
179	priv->reg_ledout_offset = tlc591xx->reg_ledout_offset;
180
181	i2c_set_clientdata(client, priv);
182
183	err = tlc591xx_set_mode(priv->regmap, MODE2_DIM);
184	if (err < 0)
185		return err;
186
187	for_each_available_child_of_node(np, child) {
188		struct tlc591xx_led *led;
189		struct led_init_data init_data = {};
190
191		init_data.fwnode = of_fwnode_handle(child);
192
193		err = of_property_read_u32(child, "reg", &reg);
194		if (err) {
195			of_node_put(child);
196			return err;
197		}
198		if (reg < 0 || reg >= tlc591xx->max_leds ||
199		    priv->leds[reg].active) {
200			of_node_put(child);
201			return -EINVAL;
202		}
203		led = &priv->leds[reg];
204
205		led->active = true;
206		led->priv = priv;
207		led->led_no = reg;
208		led->ldev.brightness_set_blocking = tlc591xx_brightness_set;
209		led->ldev.max_brightness = TLC591XX_MAX_BRIGHTNESS;
210		err = devm_led_classdev_register_ext(dev, &led->ldev,
211						     &init_data);
212		if (err < 0) {
213			of_node_put(child);
214			return dev_err_probe(dev, err,
215					     "couldn't register LED %s\n",
216					     led->ldev.name);
217		}
218	}
219	return 0;
220}
221
222static const struct i2c_device_id tlc591xx_id[] = {
223	{ "tlc59116" },
224	{ "tlc59108" },
225	{},
226};
227MODULE_DEVICE_TABLE(i2c, tlc591xx_id);
228
229static struct i2c_driver tlc591xx_driver = {
230	.driver = {
231		.name = "tlc591xx",
232		.of_match_table = of_match_ptr(of_tlc591xx_leds_match),
233	},
234	.probe = tlc591xx_probe,
235	.id_table = tlc591xx_id,
236};
237
238module_i2c_driver(tlc591xx_driver);
239
240MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
241MODULE_LICENSE("GPL");
242MODULE_DESCRIPTION("TLC591XX LED driver");
243