// SPDX-License-Identifier: GPL-2.0-only
/*
* NCP5623 Multi-LED Driver
*
* Author: Abdel Alkuor <[email protected]>
* Datasheet: https://www.onsemi.com/pdf/datasheet/ncp5623-d.pdf
*/
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/led-class-multicolor.h>
#define NCP5623_FUNCTION_OFFSET 0x5
#define NCP5623_REG(x) ((x) << NCP5623_FUNCTION_OFFSET)
#define NCP5623_SHUTDOWN_REG NCP5623_REG(0x0)
#define NCP5623_ILED_REG NCP5623_REG(0x1)
#define NCP5623_PWM_REG(index) NCP5623_REG(0x2 + (index))
#define NCP5623_UPWARD_STEP_REG NCP5623_REG(0x5)
#define NCP5623_DOWNWARD_STEP_REG NCP5623_REG(0x6)
#define NCP5623_DIMMING_TIME_REG NCP5623_REG(0x7)
#define NCP5623_MAX_BRIGHTNESS 0x1f
#define NCP5623_MAX_DIM_TIME_MS 240
#define NCP5623_DIM_STEP_MS 8
struct ncp5623 {
struct i2c_client *client;
struct led_classdev_mc mc_dev;
struct mutex lock;
int current_brightness;
unsigned long delay;
};
static int ncp5623_write(struct i2c_client *client, u8 reg, u8 data)
{
return i2c_smbus_write_byte_data(client, reg | data, 0);
}
static int ncp5623_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
struct ncp5623 *ncp = container_of(mc_cdev, struct ncp5623, mc_dev);
int ret;
guard(mutex)(&ncp->lock);
if (ncp->delay && time_is_after_jiffies(ncp->delay))
return -EBUSY;
ncp->delay = 0;
for (int i = 0; i < mc_cdev->num_colors; i++) {
ret = ncp5623_write(ncp->client,
NCP5623_PWM_REG(mc_cdev->subled_info[i].channel),
min(mc_cdev->subled_info[i].intensity,
NCP5623_MAX_BRIGHTNESS));
if (ret)
return ret;
}
ret = ncp5623_write(ncp->client, NCP5623_DIMMING_TIME_REG, 0);
if (ret)
return ret;
ret = ncp5623_write(ncp->client, NCP5623_ILED_REG, brightness);
if (ret)
return ret;
ncp->current_brightness = brightness;
return 0;
}
static int ncp5623_pattern_set(struct led_classdev *cdev,
struct led_pattern *pattern,
u32 len, int repeat)
{
struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
struct ncp5623 *ncp = container_of(mc_cdev, struct ncp5623, mc_dev);
int brightness_diff;
u8 reg;
int ret;
guard(mutex)(&ncp->lock);
if (ncp->delay && time_is_after_jiffies(ncp->delay))
return -EBUSY;
ncp->delay = 0;
if (pattern[0].delta_t > NCP5623_MAX_DIM_TIME_MS ||
(pattern[0].delta_t % NCP5623_DIM_STEP_MS) != 0)
return -EINVAL;
brightness_diff = pattern[0].brightness - ncp->current_brightness;
if (brightness_diff == 0)
return 0;
if (pattern[0].delta_t) {
if (brightness_diff > 0)
reg = NCP5623_UPWARD_STEP_REG;
else
reg = NCP5623_DOWNWARD_STEP_REG;
} else {
reg = NCP5623_ILED_REG;
}
ret = ncp5623_write(ncp->client, reg,
min(pattern[0].brightness, NCP5623_MAX_BRIGHTNESS));
if (ret)
return ret;
ret = ncp5623_write(ncp->client,
NCP5623_DIMMING_TIME_REG,
pattern[0].delta_t / NCP5623_DIM_STEP_MS);
if (ret)
return ret;
/*
* During testing, when the brightness difference is 1, for some
* unknown reason, the time factor it takes to change to the new
* value is the longest time possible. Otherwise, the time factor
* is simply the brightness difference.
*
* For example:
* current_brightness = 20 and new_brightness = 21 then the time it
* takes to set the new brightness increments to the maximum possible
* brightness from 20 then from 0 to 21.
* time_factor = max_brightness - 20 + 21
*/
if (abs(brightness_diff) == 1)
ncp->delay = NCP5623_MAX_BRIGHTNESS + brightness_diff;
else
ncp->delay = abs(brightness_diff);
ncp->delay = msecs_to_jiffies(ncp->delay * pattern[0].delta_t) + jiffies;
ncp->current_brightness = pattern[0].brightness;
return 0;
}
static int ncp5623_pattern_clear(struct led_classdev *led_cdev)
{
return 0;
}
static int ncp5623_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct fwnode_handle *mc_node, *led_node;
struct led_init_data init_data = { };
int num_subleds = 0;
struct ncp5623 *ncp;
struct mc_subled *subled_info;
u32 color_index;
u32 reg;
int ret;
ncp = devm_kzalloc(dev, sizeof(*ncp), GFP_KERNEL);
if (!ncp)
return -ENOMEM;
ncp->client = client;
mc_node = device_get_named_child_node(dev, "multi-led");
if (!mc_node)
return -EINVAL;
fwnode_for_each_child_node(mc_node, led_node)
num_subleds++;
subled_info = devm_kcalloc(dev, num_subleds, sizeof(*subled_info), GFP_KERNEL);
if (!subled_info) {
ret = -ENOMEM;
goto release_mc_node;
}
fwnode_for_each_available_child_node(mc_node, led_node) {
ret = fwnode_property_read_u32(led_node, "color", &color_index);
if (ret)
goto release_led_node;
ret = fwnode_property_read_u32(led_node, "reg", ®);
if (ret)
goto release_led_node;
subled_info[ncp->mc_dev.num_colors].channel = reg;
subled_info[ncp->mc_dev.num_colors++].color_index = color_index;
}
init_data.fwnode = mc_node;
ncp->mc_dev.led_cdev.max_brightness = NCP5623_MAX_BRIGHTNESS;
ncp->mc_dev.subled_info = subled_info;
ncp->mc_dev.led_cdev.brightness_set_blocking = ncp5623_brightness_set;
ncp->mc_dev.led_cdev.pattern_set = ncp5623_pattern_set;
ncp->mc_dev.led_cdev.pattern_clear = ncp5623_pattern_clear;
ncp->mc_dev.led_cdev.default_trigger = "pattern";
mutex_init(&ncp->lock);
i2c_set_clientdata(client, ncp);
ret = led_classdev_multicolor_register_ext(dev, &ncp->mc_dev, &init_data);
if (ret)
goto destroy_lock;
return 0;
destroy_lock:
mutex_destroy(&ncp->lock);
release_mc_node:
fwnode_handle_put(mc_node);
return ret;
release_led_node:
fwnode_handle_put(led_node);
goto release_mc_node;
}
static void ncp5623_remove(struct i2c_client *client)
{
struct ncp5623 *ncp = i2c_get_clientdata(client);
mutex_lock(&ncp->lock);
ncp->delay = 0;
mutex_unlock(&ncp->lock);
ncp5623_write(client, NCP5623_DIMMING_TIME_REG, 0);
led_classdev_multicolor_unregister(&ncp->mc_dev);
mutex_destroy(&ncp->lock);
}
static void ncp5623_shutdown(struct i2c_client *client)
{
struct ncp5623 *ncp = i2c_get_clientdata(client);
if (!(ncp->mc_dev.led_cdev.flags & LED_RETAIN_AT_SHUTDOWN))
ncp5623_write(client, NCP5623_SHUTDOWN_REG, 0);
mutex_destroy(&ncp->lock);
}
static const struct of_device_id ncp5623_id[] = {
{ .compatible = "onnn,ncp5623" },
{ }
};
MODULE_DEVICE_TABLE(of, ncp5623_id);
static struct i2c_driver ncp5623_i2c_driver = {
.driver = {
.name = "ncp5623",
.of_match_table = ncp5623_id,
},
.probe = ncp5623_probe,
.remove = ncp5623_remove,
.shutdown = ncp5623_shutdown,
};
module_i2c_driver(ncp5623_i2c_driver);
MODULE_AUTHOR("Abdel Alkuor <[email protected]>");
MODULE_DESCRIPTION("NCP5623 Multi-LED driver");
MODULE_LICENSE("GPL");
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