// SPDX-License-Identifier: GPL-2.0-only /* * LED driver for TI lp3952 controller * * Copyright (C) 2016, DAQRI, LLC. * Author: Tony Makkiel <tony.makkiel@daqri.com> */ #include <linux/delay.h> #include <linux/gpio.h> #include <linux/i2c.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/leds.h> #include <linux/leds-lp3952.h> #include <linux/module.h> #include <linux/notifier.h> #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/reboot.h> #include <linux/regmap.h> static int lp3952_register_write(struct i2c_client *client, u8 reg, u8 val) { int ret; struct lp3952_led_array *priv = i2c_get_clientdata(client); ret = regmap_write(priv->regmap, reg, val); if (ret) dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", __func__, reg, val, ret); return ret; } static void lp3952_on_off(struct lp3952_led_array *priv, enum lp3952_leds led_id, bool on) { int ret, val; dev_dbg(&priv->client->dev, "%s LED %d to %d\n", __func__, led_id, on); val = 1 << led_id; if (led_id == LP3952_LED_ALL) val = LP3952_LED_MASK_ALL; ret = regmap_update_bits(priv->regmap, LP3952_REG_LED_CTRL, val, on ? val : 0); if (ret) dev_err(&priv->client->dev, "%s, Error %d\n", __func__, ret); } /* * Using Imax to control brightness. There are 4 possible * setting 25, 50, 75 and 100 % of Imax. Possible values are * values 0-4. 0 meaning turn off. */ static int lp3952_set_brightness(struct led_classdev *cdev, enum led_brightness value) { unsigned int reg, shift_val; struct lp3952_ctrl_hdl *led = container_of(cdev, struct lp3952_ctrl_hdl, cdev); struct lp3952_led_array *priv = (struct lp3952_led_array *)led->priv; dev_dbg(cdev->dev, "Brightness request: %d on %d\n", value, led->channel); if (value == LED_OFF) { lp3952_on_off(priv, led->channel, false); return 0; } if (led->channel > LP3952_RED_1) { dev_err(cdev->dev, " %s Invalid LED requested", __func__); return -EINVAL; } if (led->channel >= LP3952_BLUE_1) { reg = LP3952_REG_RGB1_MAX_I_CTRL; shift_val = (led->channel - LP3952_BLUE_1) * 2; } else { reg = LP3952_REG_RGB2_MAX_I_CTRL; shift_val = led->channel * 2; } /* Enable the LED in case it is not enabled already */ lp3952_on_off(priv, led->channel, true); return regmap_update_bits(priv->regmap, reg, 3 << shift_val, --value << shift_val); } static int lp3952_get_label(struct device *dev, const char *label, char *dest) { int ret; const char *str; ret = device_property_read_string(dev, label, &str); if (ret) return ret; strncpy(dest, str, LP3952_LABEL_MAX_LEN); return 0; } static int lp3952_register_led_classdev(struct lp3952_led_array *priv) { int i, acpi_ret, ret = -ENODEV; static const char *led_name_hdl[LP3952_LED_ALL] = { "blue2", "green2", "red2", "blue1", "green1", "red1" }; for (i = 0; i < LP3952_LED_ALL; i++) { acpi_ret = lp3952_get_label(&priv->client->dev, led_name_hdl[i], priv->leds[i].name); if (acpi_ret) continue; priv->leds[i].cdev.name = priv->leds[i].name; priv->leds[i].cdev.brightness = LED_OFF; priv->leds[i].cdev.max_brightness = LP3952_BRIGHT_MAX; priv->leds[i].cdev.brightness_set_blocking = lp3952_set_brightness; priv->leds[i].channel = i; priv->leds[i].priv = priv; ret = devm_led_classdev_register(&priv->client->dev, &priv->leds[i].cdev); if (ret < 0) { dev_err(&priv->client->dev, "couldn't register LED %s\n", priv->leds[i].cdev.name); break; } } return ret; } static int lp3952_set_pattern_gen_cmd(struct lp3952_led_array *priv, u8 cmd_index, u8 r, u8 g, u8 b, enum lp3952_tt tt, enum lp3952_cet cet) { int ret; struct ptrn_gen_cmd line = { { { .r = r, .g = g, .b = b, .cet = cet, .tt = tt } } }; if (cmd_index >= LP3952_CMD_REG_COUNT) return -EINVAL; ret = lp3952_register_write(priv->client, LP3952_REG_CMD_0 + cmd_index * 2, line.bytes.msb); if (ret) return ret; return lp3952_register_write(priv->client, LP3952_REG_CMD_0 + cmd_index * 2 + 1, line.bytes.lsb); } static int lp3952_configure(struct lp3952_led_array *priv) { int ret; /* Disable any LEDs on from any previous conf. */ ret = lp3952_register_write(priv->client, LP3952_REG_LED_CTRL, 0); if (ret) return ret; /* enable rgb patter, loop */ ret = lp3952_register_write(priv->client, LP3952_REG_PAT_GEN_CTRL, LP3952_PATRN_LOOP | LP3952_PATRN_GEN_EN); if (ret) return ret; /* Update Bit 6 (Active mode), Select both Led sets, Bit [1:0] */ ret = lp3952_register_write(priv->client, LP3952_REG_ENABLES, LP3952_ACTIVE_MODE | LP3952_INT_B00ST_LDR); if (ret) return ret; /* Set Cmd1 for RGB intensity,cmd and transition time */ return lp3952_set_pattern_gen_cmd(priv, 0, I46, I71, I100, TT0, CET197); } static const struct regmap_config lp3952_regmap = { .reg_bits = 8, .val_bits = 8, .max_register = REG_MAX, .cache_type = REGCACHE_RBTREE, }; static int lp3952_probe(struct i2c_client *client, const struct i2c_device_id *id) { int status; struct lp3952_led_array *priv; priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->client = client; priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst", GPIOD_OUT_HIGH); if (IS_ERR(priv->enable_gpio)) { status = PTR_ERR(priv->enable_gpio); dev_err(&client->dev, "Failed to enable gpio: %d\n", status); return status; } priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap); if (IS_ERR(priv->regmap)) { int err = PTR_ERR(priv->regmap); dev_err(&client->dev, "Failed to allocate register map: %d\n", err); return err; } i2c_set_clientdata(client, priv); status = lp3952_configure(priv); if (status) { dev_err(&client->dev, "Probe failed. Device not found (%d)\n", status); return status; } status = lp3952_register_led_classdev(priv); if (status) { dev_err(&client->dev, "Unable to register led_classdev: %d\n", status); return status; } return 0; } static int lp3952_remove(struct i2c_client *client) { struct lp3952_led_array *priv; priv = i2c_get_clientdata(client); lp3952_on_off(priv, LP3952_LED_ALL, false); gpiod_set_value(priv->enable_gpio, 0); return 0; } static const struct i2c_device_id lp3952_id[] = { {LP3952_NAME, 0}, {} }; MODULE_DEVICE_TABLE(i2c, lp3952_id); static struct i2c_driver lp3952_i2c_driver = { .driver = { .name = LP3952_NAME, }, .probe = lp3952_probe, .remove = lp3952_remove, .id_table = lp3952_id, }; module_i2c_driver(lp3952_i2c_driver); MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>"); MODULE_DESCRIPTION("lp3952 I2C LED controller driver"); MODULE_LICENSE("GPL v2");