On 11/13/2017 02:50 PM, Dan Murphy wrote: > Introducing the LM3692x Dual-String white LED driver. > > Data sheet is located > http://www.ti.com/lit/ds/snvsa29/snvsa29.pdf > > Signed-off-by: Dan Murphy <dmurphy@xxxxxx> > --- > drivers/leds/leds-lm3692x.c | 380 ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 380 insertions(+) > create mode 100644 drivers/leds/leds-lm3692x.c > > diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c > new file mode 100644 > index 000000000000..beb753abc7b0 > --- /dev/null > +++ b/drivers/leds/leds-lm3692x.c > @@ -0,0 +1,380 @@ > +/* > + * TI lm3692x LED Driver > + * > + * Copyright (C) 2017 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 LM3692X_LED_NAME "lm3692x_led" > + > +#define LM3692X_REV 0x0 > +#define LM3692X_RESET 0x1 > +#define LM3692X_EN 0x10 > +#define LM3692X_BRT_CTRL 0x11 > +#define LM3692X_PWM_CTRL 0x12 > +#define LM3692X_BOOST_CTRL 0x13 > +#define LM3692X_AUTO_FREQ_HI 0x15 > +#define LM3692X_AUTO_FREQ_LO 0x16 > +#define LM3692X_BL_ADJ_THRESH 0x17 > +#define LM3692X_BRT_LSB 0x18 > +#define LM3692X_BRT_MSB 0x19 > +#define LM3692X_FAULT_CTRL 0x1e > +#define LM3692X_FAULT_FLAGS 0x1f > + > +#define LM3692X_SW_RESET BIT(0) > +#define LM3692X_DEVICE_EN BIT(0) > +#define LM3692X_LED1_EN BIT(1) > +#define LM3692X_LED2_EN BIT(2) > + > +/* Brightness Control Bits */ > +#define LM3692X_BL_ADJ_POL BIT(0) > +#define LM3692X_RAMP_RATE_125us 0x00 > +#define LM3692X_RAMP_RATE_250us BIT(1) > +#define LM3692X_RAMP_RATE_500us BIT(2) > +#define LM3692X_RAMP_RATE_1ms (BIT(1) | BIT(2)) > +#define LM3692X_RAMP_RATE_2ms BIT(3) > +#define LM3692X_RAMP_RATE_4ms (BIT(3) | BIT(1)) > +#define LM3692X_RAMP_RATE_8ms (BIT(2) | BIT(3)) > +#define LM3692X_RAMP_RATE_16ms (BIT(1) | BIT(2) | BIT(3)) > +#define LM3692X_RAMP_EN BIT(4) > +#define LM3692X_BRHT_MODE_REG 0x00 > +#define LM3692X_BRHT_MODE_PWM BIT(5) > +#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6) > +#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6)) > +#define LM3692X_MAP_MODE_EXP BIT(7) > + > +/* PWM Register Bits */ > +#define LM3692X_PWM_FILTER_100 BIT(0) > +#define LM3692X_PWM_FILTER_150 BIT(1) > +#define LM3692X_PWM_FILTER_200 (BIT(0) | BIT(1)) > +#define LM3692X_PWM_HYSTER_1LSB BIT(2) > +#define LM3692X_PWM_HYSTER_2LSB BIT(3) > +#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2)) > +#define LM3692X_PWM_HYSTER_4LSB BIT(4) > +#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2)) > +#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3)) > +#define LM3692X_PWM_POLARITY BIT(5) > +#define LM3692X_PWM_SAMP_4MHZ BIT(6) > +#define LM3692X_PWM_SAMP_24MHZ BIT(7) > + > +/* Boost Control Bits */ > +#define LM3692X_OCP_PROT_1A BIT(0) > +#define LM3692X_OCP_PROT_1_25A BIT(1) > +#define LM3692X_OCP_PROT_1_5A (BIT(0) | BIT(1)) > +#define LM3692X_OVP_21V BIT(2) > +#define LM3692X_OVP_25V BIT(3) > +#define LM3692X_OVP_29V (BIT(2) | BIT(3)) > +#define LM3692X_MIN_IND_22UH BIT(4) > +#define LM3692X_BOOST_SW_1MHZ BIT(5) > +#define LM3692X_BOOST_SW_NO_SHIFT BIT(6) > + > +/* Fault Control Bits */ > +#define LM3692X_FAULT_CTRL_OVP BIT(0) > +#define LM3692X_FAULT_CTRL_OCP BIT(1) > +#define LM3692X_FAULT_CTRL_TSD BIT(2) > +#define LM3692X_FAULT_CTRL_OPEN BIT(3) > + > +/* Fault Flag Bits */ > +#define LM3692X_FAULT_FLAG_OVP BIT(0) > +#define LM3692X_FAULT_FLAG_OCP BIT(1) > +#define LM3692X_FAULT_FLAG_TSD BIT(2) > +#define LM3692X_FAULT_FLAG_SHRT BIT(3) > +#define LM3692X_FAULT_FLAG_OPEN BIT(4) > + > +/** > + * struct lm3692x_led - > + * @lock - Lock for reading/writing the device > + * @client - Pointer to the I2C client > + * @led_dev - led class device pointer > + * @regmap - Devices register map > + * @enable_gpio - VDDIO/EN gpio to enable communication interface > + * @regulator - LED supply regulator pointer > + * @label - LED label > + **/ > +struct lm3692x_led { > + struct mutex lock; > + struct i2c_client *client; > + struct led_classdev led_dev; > + struct regmap *regmap; > + struct gpio_desc *enable_gpio; > + struct regulator *regulator; > + const char *label; > +}; > + > +static const struct reg_default lm3692x_reg_defs[] = { > + {LM3692X_EN, 0xf}, > + {LM3692X_BRT_CTRL, 0x61}, > + {LM3692X_PWM_CTRL, 0x73}, > + {LM3692X_BOOST_CTRL, 0x6f}, > + {LM3692X_AUTO_FREQ_HI, 0x0}, > + {LM3692X_AUTO_FREQ_LO, 0x0}, > + {LM3692X_BL_ADJ_THRESH, 0x0}, > + {LM3692X_BRT_LSB, 0x7}, > + {LM3692X_BRT_MSB, 0xff}, > + {LM3692X_FAULT_CTRL, 0x7}, > +}; > + > +static const struct regmap_config lm3692x_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > + > + .max_register = LM3692X_FAULT_FLAGS, > + .reg_defaults = lm3692x_reg_defs, > + .num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs), > + .cache_type = REGCACHE_RBTREE, > +}; > + > +static int lm3692x_fault_check(struct lm3692x_led *led) > +{ > + int ret, fault; > + unsigned int read_buf; > + > + ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf); > + if (ret) > + goto out; > + > + fault = read_buf; > + > + if (fault) > + dev_err(&led->client->dev, "Detected a fault 0x%X\n", > + fault); > +out: > + return ret; > +} > + > +static int lm3692x_brightness_set(struct led_classdev *led_cdev, > + enum led_brightness brt_val) > +{ > + struct lm3692x_led *led = > + container_of(led_cdev, struct lm3692x_led, led_dev); > + int led_brightness = (brt_val << 4) + 7; After a peer review with the hardware team it was determined that the brightness value calculation always sets the LSB to a value of 7. Therefore this will be changed in patch v2 so that the MSB will contain the brt_val and the LSB will contain the 3 MSB bits of the brt_val. So the values will look something like this: Code 0x00 thru code 0x1f --> LSB = 0 Code 0x20 thru code 0x3f --> LSB = 1, 0x101 up to 0x1f9 Code 0x40 thru code 0x5f --> LSB = 2, 0x202 up to 0x2fa Code 0x60 thru code 0x7f --> LSB = 3, 0x303 thru 0x3fb Code 0x80 thru code 0x9f --> LSB = 4, 0x404 thru 0x4fc . . Code 0xe0 thru code 0xff --> LSB = 7, 0x707 thru 0x7ff > + int ret; > + > + if (brt_val == LED_OFF) > + led_brightness = 0; > + > + mutex_lock(&led->lock); > + > + ret = lm3692x_fault_check(led); > + if (ret) { > + dev_err(&led->client->dev, "Cannot read/clear faults\n"); > + goto out; > + } > + > + ret = regmap_write(led->regmap, LM3692X_BRT_MSB, > + (led_brightness & 0xff0) >> 4); > + if (ret) { > + dev_err(&led->client->dev, "Cannot write MSB\n"); > + goto out; > + } > + > + ret = regmap_write(led->regmap, LM3692X_BRT_LSB, > + led_brightness & 0x07); > + if (ret) { > + dev_err(&led->client->dev, "Cannot write LSB\n"); > + goto out; > + } > +out: > + mutex_unlock(&led->lock); > + return ret; > +} > + > +static int lm3692x_init(struct lm3692x_led *led) > +{ > + int ret; > + > + if (led->regulator) { > + ret = regulator_enable(led->regulator); > + if (ret) > + dev_err(&led->client->dev, > + "Failed to enable regulator\n"); > + } > + > + if (led->enable_gpio) > + gpiod_direction_output(led->enable_gpio, 1); > + > + ret = lm3692x_fault_check(led); > + if (ret) { > + dev_err(&led->client->dev, "Cannot read/clear faults\n"); > + goto out; > + } > + > + ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00); > + if (ret) > + dev_err(&led->client->dev, "Fail writing BRT CTRL\n"); > + /* > + * For glitch free operation, the following data should > + * only be written while device enable bit is 0 > + * Per Section 7.5.14 of the data sheet > + */ > + ret = regmap_write(led->regmap, LM3692X_PWM_CTRL, > + LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ); > + if (ret) > + dev_err(&led->client->dev, "Failed programming PWM CTRL\n"); > + > + ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL, > + LM3692X_BRHT_MODE_RAMP_MULTI | > + LM3692X_BL_ADJ_POL | > + LM3692X_RAMP_RATE_250us); > + if (ret) > + dev_err(&led->client->dev, "Failed programming BOOST CTRL\n"); > + > + ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00); > + if (ret) > + dev_err(&led->client->dev, "Failed programming AUTO HI FREQ\n"); > + > + ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00); > + if (ret) > + dev_err(&led->client->dev, "Failed programming AUTO LO FREQ\n"); > + > + > + ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00); > + if (ret) > + dev_err(&led->client->dev, "Failed programming BL Threshold\n"); > + > + ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, > + LM3692X_BL_ADJ_POL | LM3692X_PWM_HYSTER_4LSB); > + if (ret) > + dev_err(&led->client->dev, "Failed programming BRT CTRL\n"); > + > + return ret; > +out: > + > + 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 ret; > +} > + > +static int lm3692x_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + int ret; > + struct lm3692x_led *led; > + struct device_node *np = client->dev.of_node; > + > + led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); > + if (!led) > + return -ENOMEM; > + > + if (client->dev.of_node) { > + ret = of_property_read_string(np, "label", &led->label); > + if (ret) > + led->label = LM3692X_LED_NAME; > + } > + > + led->enable_gpio = devm_gpiod_get_optional(&client->dev, > + "enable", GPIOD_OUT_LOW); > + if (IS_ERR(led->enable_gpio)) { > + ret = PTR_ERR(led->enable_gpio); > + dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret); > + return ret; > + } > + > + 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_blocking = lm3692x_brightness_set; > + > + mutex_init(&led->lock); > + > + i2c_set_clientdata(client, led); > + > + led->regmap = devm_regmap_init_i2c(client, &lm3692x_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; > + } > + > + ret = lm3692x_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 lm3692x_remove(struct i2c_client *client) > +{ > + struct lm3692x_led *led = i2c_get_clientdata(client); > + int ret; > + > + led_classdev_unregister(&led->led_dev); > + > + 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 lm3692x_id[] = { > + { "lm3692x", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, lm3692x_id); > + > +#ifdef CONFIG_OF > +static const struct of_device_id of_lm3692x_leds_match[] = { > + { .compatible = "ti,lm3692x", }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match); > +#endif > + > +static struct i2c_driver lm3692x_driver = { > + .driver = { > + .name = "lm3692x", > + .of_match_table = of_match_ptr(of_lm3692x_leds_match), > + }, > + .probe = lm3692x_probe, > + .remove = lm3692x_remove, > + .id_table = lm3692x_id, > +}; > +module_i2c_driver(lm3692x_driver); > + > +MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver"); > +MODULE_AUTHOR("Dan Murphy <dmurphy@xxxxxx>"); > +MODULE_LICENSE("GPL"); > -- ------------------ Dan Murphy -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
