[PATCH v3] leds: lp8860: Introduce TI lp8860 4 channel LED driver

From: Dan Murphy
Date: Wed Nov 19 2014 - 07:48:50 EST


Introduce the Texas Instruments lp8860
4 channel LED driver.

This driver configures the device in display cluster mode
as this seems to be the most used configuration at the
time of the driver configuration.

For more product information please see the link below:
http://www.ti.com/product/lp8860-q1

Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
---

v3 - Fixed 0day build issue with adding static to eeprom_disp_regs
v2 - Fixed commit message spelling, changed flush_work to
cancel_work, did not move INIT_WORK as led class is not registered
until the end of probe - https://patchwork.kernel.org/patch/5296361

.../devicetree/bindings/leds/leds-lp8860.txt | 29 ++
drivers/leds/Kconfig | 10 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-lp8860.c | 491 +++++++++++++++++++++
4 files changed, 531 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-lp8860.txt
create mode 100644 drivers/leds/leds-lp8860.c

diff --git a/Documentation/devicetree/bindings/leds/leds-lp8860.txt b/Documentation/devicetree/bindings/leds/leds-lp8860.txt
new file mode 100644
index 0000000..aad38dd
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-lp8860.txt
@@ -0,0 +1,29 @@
+* Texas Instruments - lp8860 4-Channel LED Driver
+
+The LP8860-Q1 is an high-efficiency LED
+driver with boost controller. It has 4 high-precision
+current sinks that can be controlled by a PWM input
+signal, a SPI/I2C master, or both.
+
+Required properties:
+ - compatible:
+ "ti,lp8860"
+ - reg - I2C slave address
+ - label - Used for naming LEDs
+
+Optional properties:
+ - enable-gpio - gpio pin to enable/disable the device.
+ - supply - "vled" - LED supply
+
+Example:
+
+leds: leds@6 {
+ compatible = "ti,lp8860";
+ reg = <0x2d>;
+ label = "display_cluster";
+ enable-gpio = <&gpio1 28 GPIO_ACTIVE_HIGH>;
+ vled-supply = <&vbatt>;
+}
+
+For more product information please see the link below:
+http://www.ti.com/product/lp8860-q1
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a210338..b0dce59 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -250,6 +250,16 @@ config LEDS_LP8788
help
This option enables support for the Keyboard LEDs on the LP8788 PMIC.

+config LEDS_LP8860
+ tristate "LED support for the TI LP8860 4 channel LED driver"
+ depends on LEDS_CLASS && REGMAP_I2C
+ help
+ If you say yes here you get support for the TI LP8860 4 channel
+ LED driver.
+ This option enables support for the display cluster LEDs
+ on the LP8860 4 channel LED driver using the I2C communication
+ bus.
+
config LEDS_CLEVO_MAIL
tristate "Mail LED on Clevo notebook"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index a2b1647..1c65a19 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_LEDS_LP5523) += leds-lp5523.o
obj-$(CONFIG_LEDS_LP5562) += leds-lp5562.o
obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o
obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o
+obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o
obj-$(CONFIG_LEDS_TCA6507) += leds-tca6507.o
obj-$(CONFIG_LEDS_CLEVO_MAIL) += leds-clevo-mail.o
obj-$(CONFIG_LEDS_IPAQ_MICRO) += leds-ipaq-micro.o
diff --git a/drivers/leds/leds-lp8860.c b/drivers/leds/leds-lp8860.c
new file mode 100644
index 0000000..840e93f3
--- /dev/null
+++ b/drivers/leds/leds-lp8860.c
@@ -0,0 +1,491 @@
+/*
+ * TI LP8860 4-Channel LED Driver
+ *
+ * Copyright (C) 2014 Texas Instruments
+ *
+ * Author: Dan Murphy <dmurphy@xxxxxx>
+ *
+ * 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/i2c.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/slab.h>
+
+#define LP8860_DISP_CL1_BRT_MSB 0x00
+#define LP8860_DISP_CL1_BRT_LSB 0x01
+#define LP8860_DISP_CL1_CURR_MSB 0x02
+#define LP8860_DISP_CL1_CURR_LSB 0x03
+#define LP8860_CL2_BRT_MSB 0x04
+#define LP8860_CL2_BRT_LSB 0x05
+#define LP8860_CL2_CURRENT 0x06
+#define LP8860_CL3_BRT_MSB 0x07
+#define LP8860_CL3_BRT_LSB 0x08
+#define LP8860_CL3_CURRENT 0x09
+#define LP8860_CL4_BRT_MSB 0x0a
+#define LP8860_CL4_BRT_LSB 0x0b
+#define LP8860_CL4_CURRENT 0x0c
+#define LP8860_CONFIG 0x0d
+#define LP8860_STATUS 0x0e
+#define LP8860_FAULT 0x0f
+#define LP8860_LED_FAULT 0x10
+#define LP8860_FAULT_CLEAR 0x11
+#define LP8860_ID 0x12
+#define LP8860_TEMP_MSB 0x13
+#define LP8860_TEMP_LSB 0x14
+#define LP8860_DISP_LED_CURR_MSB 0x15
+#define LP8860_DISP_LED_CURR_LSB 0x16
+#define LP8860_DISP_LED_PWM_MSB 0x17
+#define LP8860_DISP_LED_PWM_LSB 0x18
+#define LP8860_EEPROM_CNTRL 0x19
+#define LP8860_EEPROM_UNLOCK 0x1a
+
+#define LP8860_EEPROM_REG_0 0x60
+#define LP8860_EEPROM_REG_1 0x61
+#define LP8860_EEPROM_REG_2 0x62
+#define LP8860_EEPROM_REG_3 0x63
+#define LP8860_EEPROM_REG_4 0x64
+#define LP8860_EEPROM_REG_5 0x65
+#define LP8860_EEPROM_REG_6 0x66
+#define LP8860_EEPROM_REG_7 0x67
+#define LP8860_EEPROM_REG_8 0x68
+#define LP8860_EEPROM_REG_9 0x69
+#define LP8860_EEPROM_REG_10 0x6a
+#define LP8860_EEPROM_REG_11 0x6b
+#define LP8860_EEPROM_REG_12 0x6c
+#define LP8860_EEPROM_REG_13 0x6d
+#define LP8860_EEPROM_REG_14 0x6e
+#define LP8860_EEPROM_REG_15 0x6f
+#define LP8860_EEPROM_REG_16 0x70
+#define LP8860_EEPROM_REG_17 0x71
+#define LP8860_EEPROM_REG_18 0x72
+#define LP8860_EEPROM_REG_19 0x73
+#define LP8860_EEPROM_REG_20 0x74
+#define LP8860_EEPROM_REG_21 0x75
+#define LP8860_EEPROM_REG_22 0x76
+#define LP8860_EEPROM_REG_23 0x77
+#define LP8860_EEPROM_REG_24 0x78
+
+#define LP8860_LOCK_EEPROM 0x00
+#define LP8860_UNLOCK_EEPROM 0x01
+#define LP8860_PROGRAM_EEPROM 0x02
+#define LP8860_EEPROM_CODE_1 0x08
+#define LP8860_EEPROM_CODE_2 0xba
+#define LP8860_EEPROM_CODE_3 0xef
+
+#define LP8860_CLEAR_FAULTS 0x01
+
+#define LP8860_DISP_LED_NAME "display_cluster"
+
+/**
+ * struct lp8860_led -
+ * @lock - Lock for reading/writing the device
+ * @work - Work item used to off load the brightness register writes
+ * @client - Pointer to the I2C client
+ * @led_dev - led class device pointer
+ * @regmap - Devices register map
+ * @eeprom_regmap - EEPROM register map
+ * @enable_gpio - VDDIO/EN gpio to enable communication interface
+ * @regulator - LED supply regulator pointer
+ * @brightness - Current brightness value requested
+ * @label - LED label
+**/
+struct lp8860_led {
+ struct mutex lock;
+ struct work_struct work;
+ struct i2c_client *client;
+ struct led_classdev led_dev;
+ struct regmap *regmap;
+ struct regmap *eeprom_regmap;
+ struct gpio_desc *enable_gpio;
+ struct regulator *regulator;
+ enum led_brightness brightness;
+ const char *label;
+};
+
+struct lp8860_eeprom_reg {
+ uint8_t reg;
+ uint8_t value;
+};
+
+static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
+ { LP8860_EEPROM_REG_0, 0xed },
+ { LP8860_EEPROM_REG_1, 0xdf },
+ { LP8860_EEPROM_REG_2, 0xdc },
+ { LP8860_EEPROM_REG_3, 0xf0 },
+ { LP8860_EEPROM_REG_4, 0xdf },
+ { LP8860_EEPROM_REG_5, 0xe5 },
+ { LP8860_EEPROM_REG_6, 0xf2 },
+ { LP8860_EEPROM_REG_7, 0x77 },
+ { LP8860_EEPROM_REG_8, 0x77 },
+ { LP8860_EEPROM_REG_9, 0x71 },
+ { LP8860_EEPROM_REG_10, 0x3f },
+ { LP8860_EEPROM_REG_11, 0xb7 },
+ { LP8860_EEPROM_REG_12, 0x17 },
+ { LP8860_EEPROM_REG_13, 0xef },
+ { LP8860_EEPROM_REG_14, 0xb0 },
+ { LP8860_EEPROM_REG_15, 0x87 },
+ { LP8860_EEPROM_REG_16, 0xce },
+ { LP8860_EEPROM_REG_17, 0x72 },
+ { LP8860_EEPROM_REG_18, 0xe5 },
+ { LP8860_EEPROM_REG_19, 0xdf },
+ { LP8860_EEPROM_REG_20, 0x35 },
+ { LP8860_EEPROM_REG_21, 0x06 },
+ { LP8860_EEPROM_REG_22, 0xdc },
+ { LP8860_EEPROM_REG_23, 0x88 },
+ { LP8860_EEPROM_REG_24, 0x3E },
+};
+
+static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
+{
+ int ret;
+
+ mutex_lock(&led->lock);
+
+ if (lock == LP8860_UNLOCK_EEPROM) {
+ ret = regmap_write(led->regmap,
+ LP8860_EEPROM_UNLOCK,
+ LP8860_EEPROM_CODE_1);
+ if (ret) {
+ dev_err(&led->client->dev, "EEPROM Unlock failed\n");
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap,
+ LP8860_EEPROM_UNLOCK,
+ LP8860_EEPROM_CODE_2);
+ if (ret) {
+ dev_err(&led->client->dev, "EEPROM Unlock failed\n");
+ goto out;
+ }
+ ret = regmap_write(led->regmap,
+ LP8860_EEPROM_UNLOCK,
+ LP8860_EEPROM_CODE_3);
+ if (ret) {
+ dev_err(&led->client->dev, "EEPROM Unlock failed\n");
+ goto out;
+ }
+ } else {
+ ret = regmap_write(led->regmap,
+ LP8860_EEPROM_UNLOCK,
+ LP8860_LOCK_EEPROM);
+ }
+
+out:
+ mutex_unlock(&led->lock);
+ return ret;
+}
+
+static int lp8860_fault_check(struct lp8860_led *led)
+{
+ int ret, fault;
+ unsigned int read_buf;
+
+ ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
+ if (ret)
+ goto out;
+
+ fault = read_buf;
+
+ ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
+ if (ret)
+ goto out;
+
+ fault |= read_buf;
+
+ /* Attempt to clear any faults */
+ if (fault)
+ ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
+ LP8860_CLEAR_FAULTS);
+out:
+ return ret;
+}
+
+static void lp8860_led_brightness_work(struct work_struct *work)
+{
+ struct lp8860_led *led = container_of(work, struct lp8860_led, work);
+ int ret;
+ int disp_brightness = led->brightness * 255;
+
+ mutex_lock(&led->lock);
+
+ ret = lp8860_fault_check(led);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot read/clear faults\n");
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
+ (disp_brightness & 0xff00) >> 8);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
+ goto out;
+ }
+
+ ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
+ disp_brightness & 0xff);
+ if (ret) {
+ dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
+ goto out;
+ }
+out:
+ mutex_unlock(&led->lock);
+}
+
+static void lp8860_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brt_val)
+{
+ struct lp8860_led *led =
+ container_of(led_cdev, struct lp8860_led, led_dev);
+
+ led->brightness = brt_val;
+ schedule_work(&led->work);
+}
+
+static int lp8860_init(struct lp8860_led *led)
+{
+ unsigned int read_buf;
+ int ret, i, reg_count;
+
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 1);
+
+ ret = lp8860_fault_check(led);
+ if (ret)
+ goto out;
+
+ ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
+ if (ret)
+ goto out;
+
+ ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
+ if (ret) {
+ dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
+ goto out;
+ }
+
+ reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
+ for (i = 0; i < reg_count; i++) {
+ ret = regmap_write(led->eeprom_regmap,
+ lp8860_eeprom_disp_regs[i].reg,
+ lp8860_eeprom_disp_regs[i].value);
+ if (ret) {
+ dev_err(&led->client->dev, "Failed writing EEPROM\n");
+ goto out;
+ }
+ }
+
+ ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
+ if (ret)
+ goto out;
+
+ ret = regmap_write(led->regmap,
+ LP8860_EEPROM_CNTRL,
+ LP8860_PROGRAM_EEPROM);
+ if (ret)
+ dev_err(&led->client->dev, "Failed programming EEPROM\n");
+out:
+ if (ret)
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 0);
+ return ret;
+}
+
+static struct reg_default lp8860_reg_defs[] = {
+ { LP8860_DISP_CL1_BRT_MSB, 0x00},
+ { LP8860_DISP_CL1_BRT_LSB, 0x00},
+ { LP8860_DISP_CL1_CURR_MSB, 0x00},
+ { LP8860_DISP_CL1_CURR_LSB, 0x00},
+ { LP8860_CL2_BRT_MSB, 0x00},
+ { LP8860_CL2_BRT_LSB, 0x00},
+ { LP8860_CL2_CURRENT, 0x00},
+ { LP8860_CL3_BRT_MSB, 0x00},
+ { LP8860_CL3_BRT_LSB, 0x00},
+ { LP8860_CL3_CURRENT, 0x00},
+ { LP8860_CL4_BRT_MSB, 0x00},
+ { LP8860_CL4_BRT_LSB, 0x00},
+ { LP8860_CL4_CURRENT, 0x00},
+ { LP8860_CONFIG, 0x00},
+ { LP8860_FAULT_CLEAR, 0x00},
+ { LP8860_EEPROM_CNTRL, 0x80},
+ { LP8860_EEPROM_UNLOCK, 0x00},
+};
+
+static const struct regmap_config lp8860_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = LP8860_EEPROM_UNLOCK,
+ .reg_defaults = lp8860_reg_defs,
+ .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
+ .cache_type = REGCACHE_NONE,
+};
+
+static struct reg_default lp8860_eeprom_defs[] = {
+ { LP8860_EEPROM_REG_0, 0x00 },
+ { LP8860_EEPROM_REG_1, 0x00 },
+ { LP8860_EEPROM_REG_2, 0x00 },
+ { LP8860_EEPROM_REG_3, 0x00 },
+ { LP8860_EEPROM_REG_4, 0x00 },
+ { LP8860_EEPROM_REG_5, 0x00 },
+ { LP8860_EEPROM_REG_6, 0x00 },
+ { LP8860_EEPROM_REG_7, 0x00 },
+ { LP8860_EEPROM_REG_8, 0x00 },
+ { LP8860_EEPROM_REG_9, 0x00 },
+ { LP8860_EEPROM_REG_10, 0x00 },
+ { LP8860_EEPROM_REG_11, 0x00 },
+ { LP8860_EEPROM_REG_12, 0x00 },
+ { LP8860_EEPROM_REG_13, 0x00 },
+ { LP8860_EEPROM_REG_14, 0x00 },
+ { LP8860_EEPROM_REG_15, 0x00 },
+ { LP8860_EEPROM_REG_16, 0x00 },
+ { LP8860_EEPROM_REG_17, 0x00 },
+ { LP8860_EEPROM_REG_18, 0x00 },
+ { LP8860_EEPROM_REG_19, 0x00 },
+ { LP8860_EEPROM_REG_20, 0x00 },
+ { LP8860_EEPROM_REG_21, 0x00 },
+ { LP8860_EEPROM_REG_22, 0x00 },
+ { LP8860_EEPROM_REG_23, 0x00 },
+ { LP8860_EEPROM_REG_24, 0x00 },
+};
+
+static const struct regmap_config lp8860_eeprom_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = LP8860_EEPROM_REG_24,
+ .reg_defaults = lp8860_eeprom_defs,
+ .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
+ .cache_type = REGCACHE_NONE,
+};
+
+static int lp8860_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct lp8860_led *led;
+ struct device_node *np = client->dev.of_node;
+
+ led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ led->label = LP8860_DISP_LED_NAME;
+
+ if (client->dev.of_node) {
+ ret = of_property_read_string(np, "label", &led->label);
+ if (ret) {
+ dev_err(&client->dev, "Missing label in dt\n");
+ return -EINVAL;
+ }
+ }
+
+ led->enable_gpio = devm_gpiod_get(&client->dev, "enable");
+ if (IS_ERR(led->enable_gpio))
+ led->enable_gpio = NULL;
+ else
+ gpiod_direction_output(led->enable_gpio, 0);
+
+ led->regulator = devm_regulator_get(&client->dev, "vled");
+ if (IS_ERR(led->regulator))
+ led->regulator = NULL;
+
+ led->client = client;
+ led->led_dev.name = led->label;
+ led->led_dev.max_brightness = LED_FULL;
+ led->led_dev.brightness_set = lp8860_brightness_set;
+
+ mutex_init(&led->lock);
+ INIT_WORK(&led->work, lp8860_led_brightness_work);
+
+ i2c_set_clientdata(client, led);
+
+ led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
+ if (IS_ERR(led->regmap)) {
+ ret = PTR_ERR(led->regmap);
+ dev_err(&client->dev, "Failed to allocate register map: %d\n",
+ ret);
+ return ret;
+ }
+
+ led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
+ if (IS_ERR(led->eeprom_regmap)) {
+ ret = PTR_ERR(led->eeprom_regmap);
+ dev_err(&client->dev, "Failed to allocate register map: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = lp8860_init(led);
+ if (ret)
+ return ret;
+
+ ret = led_classdev_register(&client->dev, &led->led_dev);
+ if (ret) {
+ dev_err(&client->dev, "led register err: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lp8860_remove(struct i2c_client *client)
+{
+ struct lp8860_led *led = i2c_get_clientdata(client);
+ int ret;
+
+ led_classdev_unregister(&led->led_dev);
+ cancel_work_sync(&led->work);
+
+ if (led->enable_gpio)
+ gpiod_direction_output(led->enable_gpio, 0);
+
+ if (led->regulator) {
+ ret = regulator_disable(led->regulator);
+ if (ret)
+ dev_err(&led->client->dev,
+ "Failed to disable regulator\n");
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id lp8860_id[] = {
+ { "lp8860", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lp8860_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_lp8860_leds_match[] = {
+ { .compatible = "ti,lp8860", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
+#endif
+
+static struct i2c_driver lp8860_driver = {
+ .driver = {
+ .name = "lp8860",
+ .of_match_table = of_match_ptr(of_lp8860_leds_match),
+ },
+ .probe = lp8860_probe,
+ .remove = lp8860_remove,
+ .id_table = lp8860_id,
+};
+module_i2c_driver(lp8860_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LP8860 LED drvier");
+MODULE_AUTHOR("Dan Murphy <dmurphy@xxxxxx>");
+MODULE_LICENSE("GPL");
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/