--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NCP5623 Multi-LED Driver
+ *
+ * Author: Abdel Alkuor <alkuor@gmail.com>
+ * 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 240 /* ms */
+#define NCP5623_DIM_STEP 8 /* ms */
+
+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 ||
+ (pattern[0].delta_t % NCP5623_DIM_STEP) != 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);
+ 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) {
+ fwnode_handle_put(led_node);
+ goto release_mc_node;
+ }
+
+ ret = fwnode_property_read_u32(led_node, "reg", ®);
+ if (ret) {
+ fwnode_handle_put(led_node);
+ goto release_mc_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;
+}
+
+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 <alkuor@gmail.com>");
+MODULE_DESCRIPTION("NCP5623 Multi-LED driver");
+MODULE_LICENSE("GPL");
projects / linux-2.6-block.git / blobdiff