// 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 <[email protected]>");
MODULE_DESCRIPTION("PCA995x LED driver");
MODULE_LICENSE("GPL");