The chip can drive 2 sets of RGB leds. Controller can
be controlled via PWM, I2C and audio synchronisation.
This driver uses I2C to communicate with the chip.
Datasheet: http://www.ti.com/lit/gpn/lp3952
Signed-off-by: Tony Makkiel <tony.makkiel@xxxxxxxxx>
---
drivers/leds/Kconfig | 13 ++
drivers/leds/Makefile | 1 +
drivers/leds/leds-lp3952.c | 289 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/leds-lp3952.h | 128 ++++++++++++++++++++
4 files changed, 431 insertions(+)
create mode 100644 drivers/leds/leds-lp3952.c
create mode 100644 include/linux/leds-lp3952.h
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 5ae2834..0f321f4 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -228,6 +228,19 @@ config LEDS_LP3944
To compile this driver as a module, choose M here: the
module will be called leds-lp3944.
+config LEDS_LP3952
+ tristate "LED Support for TI LP3952 2 channel LED driver"
+ depends on LEDS_CLASS
+ depends on I2C
+ depends on ACPI
+ select REGMAP_I2C
+ help
+ This option enables support for LEDs connected to the Texas
+ Instruments LP3952 LED driver.
+
+ To compile this driver as a module, choose M here: the
+ module will be called leds-lp3952.
+
config LEDS_LP55XX_COMMON
tristate "Common Driver for TI/National LP5521/5523/55231/5562/8501"
depends on LEDS_LP5521 || LEDS_LP5523 || LEDS_LP5562 || LEDS_LP8501
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index cb2013d..0684c86 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_LEDS_PCA9532) += leds-pca9532.o
obj-$(CONFIG_LEDS_GPIO_REGISTER) += leds-gpio-register.o
obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o
obj-$(CONFIG_LEDS_LP3944) += leds-lp3944.o
+obj-$(CONFIG_LEDS_LP3952) += leds-lp3952.o
obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o
obj-$(CONFIG_LEDS_LP5521) += leds-lp5521.o
obj-$(CONFIG_LEDS_LP5523) += leds-lp5523.o
diff --git a/drivers/leds/leds-lp3952.c b/drivers/leds/leds-lp3952.c
new file mode 100644
index 0000000..cec7374
--- /dev/null
+++ b/drivers/leds/leds-lp3952.c
@@ -0,0 +1,289 @@
+/*
+ * LED driver for TI lp3952 controller
+ *
+ * Copyright (C) 2016, DAQRI, LLC.
+ * Author: Tony Makkiel <tony.makkiel@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/acpi.h>
+#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, int 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, LED_OFF);
+ 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, 1);
+
+ return regmap_update_bits(priv->regmap, reg, 3 << shift_val,
+ --value << shift_val);
+}
+
+static int lp3952_register_led_classdev(struct lp3952_led_array *priv)
+{
+ int i, ret = -ENODEV;
+ static const char *led_name[LP3952_LED_ALL] = {
+ "lp3952:blue2",
+ "lp3952:green2",
+ "lp3952:red2",
+ "lp3952:blue1",
+ "lp3952:green1",
+ "lp3952:red1"
+ };
+
+ for (i = 0; i < LP3952_LED_ALL; i++) {
+ sprintf(priv->leds[i].name, "%s", led_name[i]);
+ 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_ctrl_hdl *leds;
+ struct lp3952_led_array *priv;
+
+ priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ leds = devm_kcalloc(&client->dev, LP3952_LED_ALL, sizeof(*leds),
+ GFP_KERNEL);
+ if (!leds) {
+ devm_kfree(&client->dev, priv);
+ return -ENOMEM;
+ }
+
+ priv->leds = leds;
+ priv->client = client;
+
+ priv->enable_gpio = devm_gpiod_get(&client->dev, NULL, 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, 0);
+ gpiod_set_value(priv->enable_gpio, 0);
+
+ return 0;
+}
+
+static const struct i2c_device_id lp3952_id[] = {
+ {LP3952_NAME, 0},
+ {}
+};
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id lp3952_acpi_match[] = {
+ {LP3952_ACPI_NAME, 0},
