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1// SPDX-License-Identifier: GPL-2.0+2// Driver for Awinic AW2013 3-channel LED driver3 4#include <linux/i2c.h>5#include <linux/leds.h>6#include <linux/module.h>7#include <linux/regulator/consumer.h>8#include <linux/mutex.h>9#include <linux/of.h>10#include <linux/regmap.h>11 12#define AW2013_MAX_LEDS 313 14/* Reset and ID register */15#define AW2013_RSTR 0x0016#define AW2013_RSTR_RESET 0x5517#define AW2013_RSTR_CHIP_ID 0x3318 19/* Global control register */20#define AW2013_GCR 0x0121#define AW2013_GCR_ENABLE BIT(0)22 23/* LED channel enable register */24#define AW2013_LCTR 0x3025#define AW2013_LCTR_LE(x) BIT((x))26 27/* LED channel control registers */28#define AW2013_LCFG(x) (0x31 + (x))29#define AW2013_LCFG_IMAX_MASK (BIT(0) | BIT(1)) // Should be 0-330#define AW2013_LCFG_MD BIT(4)31#define AW2013_LCFG_FI BIT(5)32#define AW2013_LCFG_FO BIT(6)33 34/* LED channel PWM registers */35#define AW2013_REG_PWM(x) (0x34 + (x))36 37/* LED channel timing registers */38#define AW2013_LEDT0(x) (0x37 + (x) * 3)39#define AW2013_LEDT0_T1(x) ((x) << 4) // Should be 0-740#define AW2013_LEDT0_T2(x) (x) // Should be 0-541 42#define AW2013_LEDT1(x) (0x38 + (x) * 3)43#define AW2013_LEDT1_T3(x) ((x) << 4) // Should be 0-744#define AW2013_LEDT1_T4(x) (x) // Should be 0-745 46#define AW2013_LEDT2(x) (0x39 + (x) * 3)47#define AW2013_LEDT2_T0(x) ((x) << 4) // Should be 0-848#define AW2013_LEDT2_REPEAT(x) (x) // Should be 0-1549 50#define AW2013_REG_MAX 0x7751 52#define AW2013_TIME_STEP 130 /* ms */53 54struct aw2013;55 56struct aw2013_led {57	struct aw2013 *chip;58	struct led_classdev cdev;59	u32 num;60	unsigned int imax;61};62 63struct aw2013 {64	struct mutex mutex; /* held when writing to registers */65	struct regulator_bulk_data regulators[2];66	struct i2c_client *client;67	struct aw2013_led leds[AW2013_MAX_LEDS];68	struct regmap *regmap;69	int num_leds;70	bool enabled;71};72 73static int aw2013_chip_init(struct aw2013 *chip)74{75	int i, ret;76 77	ret = regmap_write(chip->regmap, AW2013_GCR, AW2013_GCR_ENABLE);78	if (ret) {79		dev_err(&chip->client->dev, "Failed to enable the chip: %d\n",80			ret);81		return ret;82	}83 84	for (i = 0; i < chip->num_leds; i++) {85		ret = regmap_update_bits(chip->regmap,86					 AW2013_LCFG(chip->leds[i].num),87					 AW2013_LCFG_IMAX_MASK,88					 chip->leds[i].imax);89		if (ret) {90			dev_err(&chip->client->dev,91				"Failed to set maximum current for led %d: %d\n",92				chip->leds[i].num, ret);93			return ret;94		}95	}96 97	return ret;98}99 100static void aw2013_chip_disable(struct aw2013 *chip)101{102	int ret;103 104	if (!chip->enabled)105		return;106 107	regmap_write(chip->regmap, AW2013_GCR, 0);108 109	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),110				     chip->regulators);111	if (ret) {112		dev_err(&chip->client->dev,113			"Failed to disable regulators: %d\n", ret);114		return;115	}116 117	chip->enabled = false;118}119 120static int aw2013_chip_enable(struct aw2013 *chip)121{122	int ret;123 124	if (chip->enabled)125		return 0;126 127	ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),128				    chip->regulators);129	if (ret) {130		dev_err(&chip->client->dev,131			"Failed to enable regulators: %d\n", ret);132		return ret;133	}134	chip->enabled = true;135 136	ret = aw2013_chip_init(chip);137	if (ret)138		aw2013_chip_disable(chip);139 140	return ret;141}142 143static bool aw2013_chip_in_use(struct aw2013 *chip)144{145	int i;146 147	for (i = 0; i < chip->num_leds; i++)148		if (chip->leds[i].cdev.brightness)149			return true;150 151	return false;152}153 154static int aw2013_brightness_set(struct led_classdev *cdev,155				 enum led_brightness brightness)156{157	struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);158	int ret, num;159 160	mutex_lock(&led->chip->mutex);161 162	if (aw2013_chip_in_use(led->chip)) {163		ret = aw2013_chip_enable(led->chip);164		if (ret)165			goto error;166	}167 168	num = led->num;169 170	ret = regmap_write(led->chip->regmap, AW2013_REG_PWM(num), brightness);171	if (ret)172		goto error;173 174	if (brightness) {175		ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,176					 AW2013_LCTR_LE(num), 0xFF);177	} else {178		ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,179					 AW2013_LCTR_LE(num), 0);180		if (ret)181			goto error;182		ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),183					 AW2013_LCFG_MD, 0);184	}185	if (ret)186		goto error;187 188	if (!aw2013_chip_in_use(led->chip))189		aw2013_chip_disable(led->chip);190 191error:192	mutex_unlock(&led->chip->mutex);193 194	return ret;195}196 197static int aw2013_blink_set(struct led_classdev *cdev,198			    unsigned long *delay_on, unsigned long *delay_off)199{200	struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);201	int ret, num = led->num;202	unsigned long off = 0, on = 0;203 204	/* If no blink specified, default to 1 Hz. */205	if (!*delay_off && !*delay_on) {206		*delay_off = 500;207		*delay_on = 500;208	}209 210	if (!led->cdev.brightness) {211		led->cdev.brightness = LED_FULL;212		ret = aw2013_brightness_set(&led->cdev, led->cdev.brightness);213		if (ret)214			return ret;215	}216 217	/* Never on - just set to off */218	if (!*delay_on) {219		led->cdev.brightness = LED_OFF;220		return aw2013_brightness_set(&led->cdev, LED_OFF);221	}222 223	mutex_lock(&led->chip->mutex);224 225	/* Never off - brightness is already set, disable blinking */226	if (!*delay_off) {227		ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),228					 AW2013_LCFG_MD, 0);229		goto out;230	}231 232	/* Convert into values the HW will understand. */233	off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1);234	on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1);235 236	*delay_off = BIT(off) * AW2013_TIME_STEP;237	*delay_on = BIT(on) * AW2013_TIME_STEP;238 239	/* Set timings */240	ret = regmap_write(led->chip->regmap,241			   AW2013_LEDT0(num), AW2013_LEDT0_T2(on));242	if (ret)243		goto out;244	ret = regmap_write(led->chip->regmap,245			   AW2013_LEDT1(num), AW2013_LEDT1_T4(off));246	if (ret)247		goto out;248 249	/* Finally, enable the LED */250	ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),251				 AW2013_LCFG_MD, 0xFF);252	if (ret)253		goto out;254 255	ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,256				 AW2013_LCTR_LE(num), 0xFF);257 258out:259	mutex_unlock(&led->chip->mutex);260 261	return ret;262}263 264static int aw2013_probe_dt(struct aw2013 *chip)265{266	struct device_node *np = dev_of_node(&chip->client->dev);267	int count, ret = 0, i = 0;268	struct aw2013_led *led;269 270	count = of_get_available_child_count(np);271	if (!count || count > AW2013_MAX_LEDS)272		return -EINVAL;273 274	regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET);275 276	for_each_available_child_of_node_scoped(np, child) {277		struct led_init_data init_data = {};278		u32 source;279		u32 imax;280 281		ret = of_property_read_u32(child, "reg", &source);282		if (ret != 0 || source >= AW2013_MAX_LEDS) {283			dev_err(&chip->client->dev,284				"Couldn't read LED address: %d\n", ret);285			count--;286			continue;287		}288 289		led = &chip->leds[i];290		led->num = source;291		led->chip = chip;292		init_data.fwnode = of_fwnode_handle(child);293 294		if (!of_property_read_u32(child, "led-max-microamp", &imax)) {295			led->imax = min_t(u32, imax / 5000, 3);296		} else {297			led->imax = 1; // 5mA298			dev_info(&chip->client->dev,299				 "DT property led-max-microamp is missing\n");300		}301 302		led->cdev.brightness_set_blocking = aw2013_brightness_set;303		led->cdev.blink_set = aw2013_blink_set;304 305		ret = devm_led_classdev_register_ext(&chip->client->dev,306						     &led->cdev, &init_data);307		if (ret < 0)308			return ret;309 310		i++;311	}312 313	if (!count)314		return -EINVAL;315 316	chip->num_leds = i;317 318	return 0;319}320 321static void aw2013_chip_disable_action(void *data)322{323	aw2013_chip_disable(data);324}325 326static const struct regmap_config aw2013_regmap_config = {327	.reg_bits = 8,328	.val_bits = 8,329	.max_register = AW2013_REG_MAX,330};331 332static int aw2013_probe(struct i2c_client *client)333{334	struct aw2013 *chip;335	int ret;336	unsigned int chipid;337 338	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);339	if (!chip)340		return -ENOMEM;341 342	ret = devm_mutex_init(&client->dev, &chip->mutex);343	if (ret)344		return ret;345 346	mutex_lock(&chip->mutex);347 348	chip->client = client;349	i2c_set_clientdata(client, chip);350 351	chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config);352	if (IS_ERR(chip->regmap)) {353		ret = PTR_ERR(chip->regmap);354		dev_err(&client->dev, "Failed to allocate register map: %d\n",355			ret);356		goto error;357	}358 359	chip->regulators[0].supply = "vcc";360	chip->regulators[1].supply = "vio";361	ret = devm_regulator_bulk_get(&client->dev,362				      ARRAY_SIZE(chip->regulators),363				      chip->regulators);364	if (ret < 0) {365		if (ret != -EPROBE_DEFER)366			dev_err(&client->dev,367				"Failed to request regulators: %d\n", ret);368		goto error;369	}370 371	ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),372				    chip->regulators);373	if (ret) {374		dev_err(&client->dev,375			"Failed to enable regulators: %d\n", ret);376		goto error;377	}378 379	ret = regmap_read(chip->regmap, AW2013_RSTR, &chipid);380	if (ret) {381		dev_err(&client->dev, "Failed to read chip ID: %d\n",382			ret);383		goto error_reg;384	}385 386	if (chipid != AW2013_RSTR_CHIP_ID) {387		dev_err(&client->dev, "Chip reported wrong ID: %x\n",388			chipid);389		ret = -ENODEV;390		goto error_reg;391	}392 393	ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip);394	if (ret)395		goto error_reg;396 397	ret = aw2013_probe_dt(chip);398	if (ret < 0)399		goto error_reg;400 401	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),402				     chip->regulators);403	if (ret) {404		dev_err(&client->dev,405			"Failed to disable regulators: %d\n", ret);406		goto error;407	}408 409	mutex_unlock(&chip->mutex);410 411	return 0;412 413error_reg:414	regulator_bulk_disable(ARRAY_SIZE(chip->regulators),415			       chip->regulators);416 417error:418	mutex_unlock(&chip->mutex);419	return ret;420}421 422static const struct of_device_id aw2013_match_table[] = {423	{ .compatible = "awinic,aw2013", },424	{ /* sentinel */ },425};426 427MODULE_DEVICE_TABLE(of, aw2013_match_table);428 429static struct i2c_driver aw2013_driver = {430	.driver = {431		.name = "leds-aw2013",432		.of_match_table = aw2013_match_table,433	},434	.probe = aw2013_probe,435};436 437module_i2c_driver(aw2013_driver);438 439MODULE_AUTHOR("Nikita Travkin <nikitos.tr@gmail.com>");440MODULE_DESCRIPTION("AW2013 LED driver");441MODULE_LICENSE("GPL v2");442