leds-max77705.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Based on leds-max77650 driver
  4 *
  5 * LED driver for MAXIM 77705 PMIC.
  6 * Copyright (C) 2025 Dzmitry Sankouski <dsankouski@gmail.org>
  7 */
  8
  9#include <linux/i2c.h>
 10#include <linux/led-class-multicolor.h>
 11#include <linux/leds.h>
 12#include <linux/mfd/max77705-private.h>
 13#include <linux/module.h>
 14#include <linux/platform_device.h>
 15#include <linux/regmap.h>
 16
 17#define MAX77705_LED_NUM_LEDS			4
 18#define MAX77705_LED_EN_MASK			GENMASK(1, 0)
 19#define MAX77705_LED_MAX_BRIGHTNESS		0xff
 20#define MAX77705_LED_EN_SHIFT(reg)		(reg * MAX77705_RGBLED_EN_WIDTH)
 21#define MAX77705_LED_REG_BRIGHTNESS(reg)	(reg + MAX77705_RGBLED_REG_LED0BRT)
 22
 23struct max77705_led {
 24	struct led_classdev cdev;
 25	struct led_classdev_mc mcdev;
 26	struct regmap *regmap;
 27
 28	struct mc_subled *subled_info;
 29};
 30
 31static const struct regmap_config max77705_leds_regmap_config = {
 32	.reg_base = MAX77705_RGBLED_REG_BASE,
 33	.reg_bits = 8,
 34	.val_bits = 8,
 35	.max_register = MAX77705_LED_REG_END,
 36};
 37
 38static int max77705_rgb_blink(struct led_classdev *cdev,
 39				unsigned long *delay_on,
 40				unsigned long *delay_off)
 41{
 42	struct max77705_led *led = container_of(cdev, struct max77705_led, cdev);
 43	int value, on_value, off_value;
 44
 45	if (*delay_on < MAX77705_RGB_DELAY_100_STEP)
 46		on_value = 0;
 47	else if (*delay_on < MAX77705_RGB_DELAY_100_STEP_LIM)
 48		on_value = *delay_on / MAX77705_RGB_DELAY_100_STEP - 1;
 49	else if (*delay_on < MAX77705_RGB_DELAY_250_STEP_LIM)
 50		on_value = (*delay_on - MAX77705_RGB_DELAY_100_STEP_LIM) /
 51				MAX77705_RGB_DELAY_250_STEP +
 52				MAX77705_RGB_DELAY_100_STEP_COUNT;
 53	else
 54		on_value = 15;
 55
 56	on_value <<= 4;
 57
 58	if (*delay_off < 1)
 59		off_value = 0;
 60	else if (*delay_off < MAX77705_RGB_DELAY_500_STEP)
 61		off_value = 1;
 62	else if (*delay_off < MAX77705_RGB_DELAY_500_STEP_LIM)
 63		off_value = *delay_off / MAX77705_RGB_DELAY_500_STEP;
 64	else if (*delay_off < MAX77705_RGB_DELAY_1000_STEP_LIM)
 65		off_value = (*delay_off - MAX77705_RGB_DELAY_1000_STEP_LIM) /
 66				MAX77705_RGB_DELAY_1000_STEP +
 67				MAX77705_RGB_DELAY_500_STEP_COUNT;
 68	else if (*delay_off < MAX77705_RGB_DELAY_2000_STEP_LIM)
 69		off_value = (*delay_off - MAX77705_RGB_DELAY_2000_STEP_LIM) /
 70				MAX77705_RGB_DELAY_2000_STEP +
 71				MAX77705_RGB_DELAY_1000_STEP_COUNT;
 72	else
 73		off_value = 15;
 74
 75	value = on_value | off_value;
 76	return regmap_write(led->regmap, MAX77705_RGBLED_REG_LEDBLNK, value);
 77}
 78
 79static int max77705_led_brightness_set(struct regmap *regmap, struct mc_subled *subled,
 80				int num_colors)
 81{
 82	int ret;
 83
 84	for (int i = 0; i < num_colors; i++) {
 85		unsigned int channel, brightness;
 86
 87		channel = subled[i].channel;
 88		brightness = subled[i].brightness;
 89
 90		if (brightness == LED_OFF) {
 91			/* Flash OFF */
 92			ret = regmap_update_bits(regmap,
 93					MAX77705_RGBLED_REG_LEDEN,
 94					MAX77705_LED_EN_MASK << MAX77705_LED_EN_SHIFT(channel), 0);
 95		} else {
 96			/* Set current */
 97			ret = regmap_write(regmap, MAX77705_LED_REG_BRIGHTNESS(channel),
 98					brightness);
 99			if (ret < 0)
100				return ret;
101
102			ret = regmap_update_bits(regmap,
103					MAX77705_RGBLED_REG_LEDEN,
104					LED_ON << MAX77705_LED_EN_SHIFT(channel),
105					MAX77705_LED_EN_MASK << MAX77705_LED_EN_SHIFT(channel));
106		}
107	}
108
109	return ret;
110}
111
112static int max77705_led_brightness_set_single(struct led_classdev *cdev,
113					enum led_brightness brightness)
114{
115	struct max77705_led *led = container_of(cdev, struct max77705_led, cdev);
116
117	led->subled_info->brightness = brightness;
118
119	return max77705_led_brightness_set(led->regmap, led->subled_info, 1);
120}
121
122static int max77705_led_brightness_set_multi(struct led_classdev *cdev,
123					enum led_brightness brightness)
124{
125	struct led_classdev_mc *mcdev = lcdev_to_mccdev(cdev);
126	struct max77705_led *led = container_of(mcdev, struct max77705_led, mcdev);
127
128	led_mc_calc_color_components(mcdev, brightness);
129
130	return max77705_led_brightness_set(led->regmap, led->mcdev.subled_info, mcdev->num_colors);
131}
132
133static int max77705_parse_subled(struct device *dev, struct fwnode_handle *np,
134				struct mc_subled *info)
135{
136	u32 color = LED_COLOR_ID_GREEN;
137	u32 reg;
138	int ret;
139
140	ret = fwnode_property_read_u32(np, "reg", &reg);
141	if (ret || !reg || reg >= MAX77705_LED_NUM_LEDS)
142		return dev_err_probe(dev, -EINVAL, "invalid \"reg\" of %pOFn\n", np);
143
144	info->channel = reg;
145
146	ret = fwnode_property_read_u32(np, "color", &color);
147	if (ret < 0 && ret != -EINVAL)
148		return dev_err_probe(dev, ret,
149				     "failed to parse \"color\" of %pOF\n", np);
150
151	info->color_index = color;
152
153	return 0;
154}
155
156static int max77705_add_led(struct device *dev, struct regmap *regmap, struct fwnode_handle *np)
157{
158	int ret, i = 0;
159	unsigned int color, reg;
160	struct max77705_led *led;
161	struct led_classdev *cdev;
162	struct mc_subled *info;
163	struct fwnode_handle *child;
164	struct led_init_data init_data = {};
165
166	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
167	if (!led)
168		return -ENOMEM;
169
170	ret = fwnode_property_read_u32(np, "color", &color);
171	if (ret < 0 && ret != -EINVAL)
172		return dev_err_probe(dev, ret,
173			      "failed to parse \"color\" of %pOF\n", np);
174
175	led->regmap = regmap;
176	init_data.fwnode = np;
177
178	if (color == LED_COLOR_ID_RGB) {
179		int num_channels = of_get_available_child_count(to_of_node(np));
180
181		ret = fwnode_property_read_u32(np, "reg", &reg);
182		if (ret || reg >= MAX77705_LED_NUM_LEDS)
183			return -EINVAL;
184
185		info = devm_kcalloc(dev, num_channels, sizeof(*info), GFP_KERNEL);
186		if (!info)
187			return -ENOMEM;
188
189		cdev = &led->mcdev.led_cdev;
190		cdev->max_brightness = MAX77705_LED_MAX_BRIGHTNESS;
191		cdev->brightness_set_blocking = max77705_led_brightness_set_multi;
192		cdev->blink_set = max77705_rgb_blink;
193
194		fwnode_for_each_child_node(np, child) {
195			ret = max77705_parse_subled(dev, child, &info[i]);
196			if (ret < 0)
197				return ret;
198
199			info[i].intensity = 0;
200			i++;
201		}
202
203		led->mcdev.subled_info = info;
204		led->mcdev.num_colors = num_channels;
205		led->cdev = *cdev;
206
207		ret = devm_led_classdev_multicolor_register_ext(dev, &led->mcdev, &init_data);
208		if (ret)
209			return ret;
210
211		ret = max77705_led_brightness_set_multi(&led->cdev, LED_OFF);
212		if (ret)
213			return ret;
214	} else {
215		info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
216		if (!info)
217			return -ENOMEM;
218
219		max77705_parse_subled(dev, np, info);
220
221		led->subled_info = info;
222		led->cdev.brightness_set_blocking = max77705_led_brightness_set_single;
223		led->cdev.blink_set = max77705_rgb_blink;
224		led->cdev.max_brightness = MAX77705_LED_MAX_BRIGHTNESS;
225
226		ret = devm_led_classdev_register_ext(dev, &led->cdev, &init_data);
227		if (ret)
228			return ret;
229
230		ret = max77705_led_brightness_set_single(&led->cdev, LED_OFF);
231		if (ret)
232			return ret;
233	}
234
235	return 0;
236}
237
238static int max77705_led_probe(struct platform_device *pdev)
239{
240	struct device *dev = &pdev->dev;
241	struct i2c_client *i2c = to_i2c_client(pdev->dev.parent);
242	struct regmap *regmap;
243	int ret;
244
245	regmap = devm_regmap_init_i2c(i2c, &max77705_leds_regmap_config);
246	if (IS_ERR(regmap))
247		return dev_err_probe(dev, PTR_ERR(regmap), "Failed to register LEDs regmap\n");
248
249	device_for_each_child_node_scoped(dev, child) {
250		ret = max77705_add_led(dev, regmap, child);
251		if (ret)
252			return ret;
253	}
254
255	return 0;
256}
257
258static const struct of_device_id max77705_led_of_match[] = {
259	{ .compatible = "maxim,max77705-rgb" },
260	{ }
261};
262MODULE_DEVICE_TABLE(of, max77705_led_of_match);
263
264static struct platform_driver max77705_led_driver = {
265	.driver = {
266		.name = "max77705-led",
267		.of_match_table = max77705_led_of_match,
268	},
269	.probe = max77705_led_probe,
270};
271module_platform_driver(max77705_led_driver);
272
273MODULE_DESCRIPTION("Maxim MAX77705 LED driver");
274MODULE_AUTHOR("Dzmitry Sankouski <dsankouski@gmail.com>");
275MODULE_LICENSE("GPL");