diff options
Diffstat (limited to 'drivers/leds/leds-pca995x.c')
| -rw-r--r-- | drivers/leds/leds-pca995x.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/leds/leds-pca995x.c b/drivers/leds/leds-pca995x.c new file mode 100644 index 000000000000..6ad06ce2bf64 --- /dev/null +++ b/drivers/leds/leds-pca995x.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * LED driver for PCA995x I2C LED drivers + * + * Copyright 2011 bct electronic GmbH + * Copyright 2013 Qtechnology/AS + * Copyright 2022 NXP + * Copyright 2023 Marek Vasut + */ + +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/property.h> +#include <linux/regmap.h> + +/* Register definition */ +#define PCA995X_MODE1 0x00 +#define PCA995X_MODE2 0x01 +#define PCA995X_LEDOUT0 0x02 + +/* Auto-increment disabled. Normal mode */ +#define PCA995X_MODE1_CFG 0x00 + +/* LED select registers determine the source that drives LED outputs */ +#define PCA995X_LED_OFF 0x0 +#define PCA995X_LED_ON 0x1 +#define PCA995X_LED_PWM_MODE 0x2 +#define PCA995X_LDRX_MASK 0x3 +#define PCA995X_LDRX_BITS 2 + +#define PCA995X_MAX_OUTPUTS 24 +#define PCA995X_OUTPUTS_PER_REG 4 + +#define PCA995X_IREFALL_FULL_CFG 0xFF +#define PCA995X_IREFALL_HALF_CFG (PCA995X_IREFALL_FULL_CFG / 2) + +#define ldev_to_led(c) container_of(c, struct pca995x_led, ldev) + +struct pca995x_chipdef { + unsigned int num_leds; + u8 pwm_base; + u8 irefall; +}; + +static const struct pca995x_chipdef pca9952_chipdef = { + .num_leds = 16, + .pwm_base = 0x0a, + .irefall = 0x43, +}; + +static const struct pca995x_chipdef pca9955b_chipdef = { + .num_leds = 16, + .pwm_base = 0x08, + .irefall = 0x45, +}; + +static const struct pca995x_chipdef pca9956b_chipdef = { + .num_leds = 24, + .pwm_base = 0x0a, + .irefall = 0x40, +}; + +struct pca995x_led { + unsigned int led_no; + struct led_classdev ldev; + struct pca995x_chip *chip; +}; + +struct pca995x_chip { + struct regmap *regmap; + struct pca995x_led leds[PCA995X_MAX_OUTPUTS]; + const struct pca995x_chipdef *chipdef; +}; + +static int pca995x_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct pca995x_led *led = ldev_to_led(led_cdev); + struct pca995x_chip *chip = led->chip; + const struct pca995x_chipdef *chipdef = chip->chipdef; + u8 ledout_addr, pwmout_addr; + int shift, ret; + + pwmout_addr = chipdef->pwm_base + led->led_no; + ledout_addr = PCA995X_LEDOUT0 + (led->led_no / PCA995X_OUTPUTS_PER_REG); + shift = PCA995X_LDRX_BITS * (led->led_no % PCA995X_OUTPUTS_PER_REG); + + switch (brightness) { + case LED_FULL: + return regmap_update_bits(chip->regmap, ledout_addr, + PCA995X_LDRX_MASK << shift, + PCA995X_LED_ON << shift); + case LED_OFF: + return regmap_update_bits(chip->regmap, ledout_addr, + PCA995X_LDRX_MASK << shift, 0); + default: + /* Adjust brightness as per user input by changing individual PWM */ + ret = regmap_write(chip->regmap, pwmout_addr, brightness); + if (ret) + return ret; + + /* + * Change LDRx configuration to individual brightness via PWM. + * LED will stop blinking if it's doing so. + */ + return regmap_update_bits(chip->regmap, ledout_addr, + PCA995X_LDRX_MASK << shift, + PCA995X_LED_PWM_MODE << shift); + } +} + +static const struct regmap_config pca995x_regmap = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x49, +}; + +static int pca995x_probe(struct i2c_client *client) +{ + struct fwnode_handle *led_fwnodes[PCA995X_MAX_OUTPUTS] = { 0 }; + struct device *dev = &client->dev; + const struct pca995x_chipdef *chipdef; + struct pca995x_chip *chip; + struct pca995x_led *led; + int i, j, reg, ret; + + chipdef = device_get_match_data(&client->dev); + + if (!dev_fwnode(dev)) + return -ENODEV; + + chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->chipdef = chipdef; + chip->regmap = devm_regmap_init_i2c(client, &pca995x_regmap); + if (IS_ERR(chip->regmap)) + return PTR_ERR(chip->regmap); + + i2c_set_clientdata(client, chip); + + device_for_each_child_node_scoped(dev, child) { + ret = fwnode_property_read_u32(child, "reg", ®); + if (ret) + return ret; + + if (reg < 0 || reg >= PCA995X_MAX_OUTPUTS || led_fwnodes[reg]) + return -EINVAL; + + led = &chip->leds[reg]; + led_fwnodes[reg] = fwnode_handle_get(child); + led->chip = chip; + led->led_no = reg; + led->ldev.brightness_set_blocking = pca995x_brightness_set; + led->ldev.max_brightness = 255; + } + + for (i = 0; i < PCA995X_MAX_OUTPUTS; i++) { + struct led_init_data init_data = {}; + + if (!led_fwnodes[i]) + continue; + + init_data.fwnode = led_fwnodes[i]; + + ret = devm_led_classdev_register_ext(dev, + &chip->leds[i].ldev, + &init_data); + if (ret < 0) { + for (j = i; j < PCA995X_MAX_OUTPUTS; j++) + fwnode_handle_put(led_fwnodes[j]); + return dev_err_probe(dev, ret, + "Could not register LED %s\n", + chip->leds[i].ldev.name); + } + } + + /* Disable LED all-call address and set normal mode */ + ret = regmap_write(chip->regmap, PCA995X_MODE1, PCA995X_MODE1_CFG); + if (ret) + return ret; + + /* IREF Output current value for all LEDn outputs */ + return regmap_write(chip->regmap, chipdef->irefall, PCA995X_IREFALL_HALF_CFG); +} + +static const struct i2c_device_id pca995x_id[] = { + { "pca9952", .driver_data = (kernel_ulong_t)&pca9952_chipdef }, + { "pca9955b", .driver_data = (kernel_ulong_t)&pca9955b_chipdef }, + { "pca9956b", .driver_data = (kernel_ulong_t)&pca9956b_chipdef }, + {} +}; +MODULE_DEVICE_TABLE(i2c, pca995x_id); + +static const struct of_device_id pca995x_of_match[] = { + { .compatible = "nxp,pca9952", .data = &pca9952_chipdef }, + { .compatible = "nxp,pca9955b", .data = &pca9955b_chipdef }, + { .compatible = "nxp,pca9956b", .data = &pca9956b_chipdef }, + {}, +}; +MODULE_DEVICE_TABLE(of, pca995x_of_match); + +static struct i2c_driver pca995x_driver = { + .driver = { + .name = "leds-pca995x", + .of_match_table = pca995x_of_match, + }, + .probe = pca995x_probe, + .id_table = pca995x_id, +}; +module_i2c_driver(pca995x_driver); + +MODULE_AUTHOR("Isai Gaspar <isaiezequiel.gaspar@nxp.com>"); +MODULE_DESCRIPTION("PCA995x LED driver"); +MODULE_LICENSE("GPL"); |