This patch adds a driver for the 1.5A Step-Up Current Regulator for Flash LEDs. The device is programmed through a Skyworks' proprietary AS2Cwire serial digital interface. Signed-off-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> Cc: Bryan Wu <cooloney@xxxxxxxxx> Cc: Richard Purdie <rpurdie@xxxxxxxxx> --- drivers/leds/Kconfig | 6 + drivers/leds/Makefile | 1 + drivers/leds/leds-aat1290.c | 455 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 462 insertions(+) create mode 100644 drivers/leds/leds-aat1290.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 794055e..ef774fd 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -42,6 +42,12 @@ config LEDS_88PM860X This option enables support for on-chip LED drivers found on Marvell Semiconductor 88PM8606 PMIC. +config LEDS_AAT1290 + tristate "LED support for the AAT1290" + depends on LEDS_CLASS_FLASH + help + This option enables support for the LEDs on the AAT1290. + config LEDS_ATMEL_PWM tristate "LED Support using Atmel PWM outputs" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index da1a4ba..41911aa 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o # LED Platform Drivers obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o +obj-$(CONFIG_LEDS_AAT1290) += leds-aat1290.o obj-$(CONFIG_LEDS_ATMEL_PWM) += leds-atmel-pwm.o obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c new file mode 100644 index 0000000..07d7384 --- /dev/null +++ b/drivers/leds/leds-aat1290.c @@ -0,0 +1,455 @@ +/* + * LED Flash Class driver for the AAT1290 + * 1.5A Step-Up Current Regulator for Flash LEDs + * + * Copyright (C) 2014, Samsung Electronics Co., Ltd. + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * 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/delay.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/led-class-flash.h> +#include <linux/led-flash-manager.h> +#include <linux/leds.h> +#include <linux/mutex.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> +#include <linux/of.h> +#include <media/v4l2-flash.h> +#include <linux/workqueue.h> + +#define AAT1290_LED_NAME "aat1290" +#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17 +#define AAT1290_FLASH_SAFETY_TIMER_ADDR 18 +#define AAT1290_MOVIE_MODE_CONFIG_ADDR 19 +#define AAT1290_MM_CURRENT_RATIO_ADDR 20 +#define AAT1290_LATCH_TIME_US 500 +#define AAT1290_EN_SET_TICK_TIME_US 1 +#define AAT1290_MOVIE_MODE_OFF 1 +#define AAT1290_MOVIE_MODE_ON 3 +#define AAT1290_MAX_MM_CURR_PERCENT_0 16 +#define AAT1290_MAX_MM_CURR_PERCENT_100 1 +#define AAT1290_FLASH_TM_RATIO_STEP 16 + +#define AAT1290_MM_TO_FL_1_92 1 +#define AAT1290_MM_TO_FL_3_7 2 +#define AAT1290_MM_TO_FL_5_5 3 +#define AAT1290_MM_TO_FL_7_3 4 +#define AAT1290_MM_TO_FL_9 5 +#define AAT1290_MM_TO_FL_10_7 6 +#define AAT1290_MM_TO_FL_12_4 7 +#define AAT1290_MM_TO_FL_14 8 +#define AAT1290_MM_TO_FL_15_9 9 +#define AAT1290_MM_TO_FL_17_5 10 +#define AAT1290_MM_TO_FL_19_1 11 +#define AAT1290_MM_TO_FL_20_8 12 +#define AAT1290_MM_TO_FL_22_4 13 +#define AAT1290_MM_TO_FL_24 14 +#define AAT1290_MM_TO_FL_25_6 15 +#define AAT1290_MM_TO_FL_OFF 16 + +static const unsigned int flash_level_to_reg[] = { + 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 +}; + +enum aat1290_led_mode { + MODE_OFF, + MODE_TORCH, + MODE_FLASH, + MODE_FLASH_EXTERNAL, +}; + +struct aat1290_led_settings { + struct led_flash_setting torch_brightness; + struct led_flash_setting flash_brightness; + struct led_flash_setting flash_timeout; +}; + +struct aat1290_led { + struct platform_device *pdev; + struct mutex lock; + + struct led_classdev_flash ldev; + struct v4l2_flash *v4l2_flash; + + int flen_gpio; + int en_set_gpio; + + u32 max_flash_tm; + bool movie_mode; + + unsigned int torch_brightness; + unsigned int flash_timeout; + struct work_struct work_brightness_set; +}; + +static struct aat1290_led *ldev_to_led(struct led_classdev_flash *ldev) +{ + return container_of(ldev, struct aat1290_led, ldev); +} + +static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value) +{ + int i; + + gpio_set_value(led->flen_gpio, 0); + gpio_set_value(led->en_set_gpio, 0); + + udelay(10); + + /* write address */ + for (i = 0; i < addr; ++i) { + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpio_set_value(led->en_set_gpio, 0); + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpio_set_value(led->en_set_gpio, 1); + } + + udelay(AAT1290_LATCH_TIME_US); + + /* write data */ + for (i = 0; i < value; ++i) { + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpio_set_value(led->en_set_gpio, 0); + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpio_set_value(led->en_set_gpio, 1); + } + + udelay(AAT1290_LATCH_TIME_US); +} + +static void aat1290_set_flash_safety_timer(struct aat1290_led *led, + unsigned int micro_sec) +{ + struct led_classdev_flash *flash = &led->ldev; + struct led_flash_setting *flash_tm = &flash->timeout; + int flash_tm_divisor_reg = + flash_level_to_reg[(micro_sec / flash_tm->step) - 1]; + + aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR, + flash_tm_divisor_reg); +} + +static void aat1290_brightness_set(struct aat1290_led *led, + enum led_brightness brightness) +{ + mutex_lock(&led->lock); + + if (brightness == 0) { + gpio_set_value(led->flen_gpio, 0); + gpio_set_value(led->en_set_gpio, 0); + goto unlock; + } + + if (!led->movie_mode) { + aat1290_as2cwire_write(led, AAT1290_MM_CURRENT_RATIO_ADDR, + AAT1290_MM_TO_FL_1_92); + led->movie_mode = true; + } + + aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR, + AAT1290_MAX_MM_CURR_PERCENT_0 - brightness); + aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR, + AAT1290_MOVIE_MODE_ON); +unlock: + mutex_unlock(&led->lock); +} + +/* LED subsystem callbacks */ + +static void aat1290_brightness_set_work(struct work_struct *work) +{ + struct aat1290_led *led = + container_of(work, struct aat1290_led, work_brightness_set); + + aat1290_brightness_set(led, led->torch_brightness); +} + +static void aat1290_led_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + struct aat1290_led *led = ldev_to_led(flash); + + led->torch_brightness = brightness; + schedule_work(&led->work_brightness_set); +} + +static int aat1290_torch_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + struct aat1290_led *led = ldev_to_led(flash); + + aat1290_brightness_set(led, brightness); + + return 0; +} + +static int aat1290_led_flash_strobe_set(struct led_classdev_flash *flash, + bool state) + +{ + struct aat1290_led *led = ldev_to_led(flash); + struct led_classdev *led_cdev = &flash->led_cdev; + struct led_flash_setting *timeout = &flash->timeout; + + mutex_lock(&led->lock); + + if (state == 0) { + gpio_set_value(led->flen_gpio, 0); + gpio_set_value(led->en_set_gpio, 0); + goto unlock; + } + + aat1290_set_flash_safety_timer(led, timeout->val); + + /* + * To reenter movie mode after a flash event the part + * must be cycled off and back on to reset the movie + * mode and reprogrammed via the AS2Cwire. Therefore + * the brightness value needs to be updated here to + * reflect the actual state. + */ + led_cdev->brightness = 0; + led->movie_mode = false; + + gpio_set_value(led->flen_gpio, 1); + +unlock: + mutex_unlock(&led->lock); + + return 0; +} + +static int aat1290_led_flash_timeout_set(struct led_classdev_flash *flash, + u32 timeout) +{ + /* + * Don't do anything - flash timeout is cached in the led-class-flash + * core and will be applied in the strobe_set op, as writing the + * safety timer register spuriously turns the torch mode on. + */ + + return 0; +} + +static int aat1290_led_parse_dt(struct aat1290_led *led, + struct device *dev) +{ + int ret; + char *pname = "flash-timeout"; + + ret = of_property_read_u32(dev->of_node, pname, &led->max_flash_tm); + if (ret) { + dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret); + return ret; + } + + return ret; +} + +static void aat1290_init_flash_settings(struct aat1290_led *led, + struct aat1290_led_settings *s) +{ + struct led_flash_setting *setting; + + /* Init flash intensity setting */ + setting = &s->torch_brightness; + /* + * Torch current is adjustable in logarithmic fashion and thus + * it is not possible to define fixed step in microamperes. + * Instead led brightness levels are used to make possible + * setting all the supported levels from V4L2 Flash sub-device. + */ + setting->min = 1; + setting->max = 16; + setting->step = 1; + setting->val = setting->max; + + /* Init flash timeout setting */ + setting = &s->flash_timeout; + setting->min = led->max_flash_tm / AAT1290_FLASH_TM_RATIO_STEP; + setting->max = setting->min * AAT1290_FLASH_TM_RATIO_STEP; + setting->step = setting->min; + setting->val = setting->max; +} + +#ifdef CONFIG_V4L2_FLASH_LED_CLASS +static void aat1290_init_v4l2_ctrl_config(struct aat1290_led_settings *s, + struct v4l2_flash_ctrl_config *config) +{ + struct led_flash_setting *setting; + struct v4l2_ctrl_config *c; + + c = &config->torch_intensity; + setting = &s->torch_brightness; + c->min = setting->min; + c->max = setting->max; + c->step = setting->step; + c->def = setting->val; + + c = &config->flash_timeout; + setting = &s->flash_timeout; + c->min = setting->min; + c->max = setting->max; + c->step = setting->step; + c->def = setting->val; +} +#else +#define aat1290_init_v4l2_ctrl_config(s, config) +#endif + +const struct led_flash_ops flash_ops = { + .strobe_set = aat1290_led_flash_strobe_set, + .timeout_set = aat1290_led_flash_timeout_set, +}; + +static int aat1290_led_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *dev_node = pdev->dev.of_node; + struct aat1290_led *led; + struct led_classdev *led_cdev; + struct led_classdev_flash *flash; + struct v4l2_flash_ctrl_config v4l2_flash_config; + struct aat1290_led_settings settings; + int flen_gpio, enset_gpio, ret; + + led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + + led->pdev = pdev; + platform_set_drvdata(pdev, led); + + if (!dev_node) + return -ENXIO; + + flen_gpio = of_get_gpio(dev_node, 0); + if (gpio_is_valid(flen_gpio)) { + ret = gpio_request_one(flen_gpio, GPIOF_DIR_OUT, + "aat1290_flen"); + if (ret < 0) { + dev_err(dev, + "failed to request GPIO %d, error %d\n", + flen_gpio, ret); + goto error_gpio_flen; + } + } + led->flen_gpio = flen_gpio; + + enset_gpio = of_get_gpio(dev_node, 1); + if (gpio_is_valid(enset_gpio)) { + ret = gpio_request_one(enset_gpio, GPIOF_DIR_OUT, + "aat1290_en_set"); + if (ret < 0) { + dev_err(dev, + "failed to request GPIO %d, error %d\n", + enset_gpio, ret); + goto error_gpio_en_set; + } + } + led->en_set_gpio = enset_gpio; + + ret = aat1290_led_parse_dt(led, &pdev->dev); + if (ret < 0) + goto error_gpio_en_set; + + mutex_init(&led->lock); + + flash = &led->ldev; + + /* Init flash settings */ + aat1290_init_flash_settings(led, &settings); + /* Init V4L2 Flash controls basing on initialized settings */ + aat1290_init_v4l2_ctrl_config(&settings, &v4l2_flash_config); + + /* Init led class */ + led_cdev = &flash->led_cdev; + led_cdev->name = AAT1290_LED_NAME; + led_cdev->brightness_set = aat1290_led_brightness_set; + led_cdev->torch_brightness_set = aat1290_torch_brightness_set; + led_cdev->max_brightness = AAT1290_MAX_MM_CURR_PERCENT_0 - + AAT1290_MAX_MM_CURR_PERCENT_100; + led_cdev->flags |= LED_DEV_CAP_FLASH; + + INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work); + + flash->ops = &flash_ops; + + flash->timeout = settings.flash_timeout; + + /* Register in the LED subsystem. */ + ret = led_classdev_flash_register(&pdev->dev, flash, dev->of_node); + if (ret < 0) + goto error_gpio_en_set; + + /* Create V4L2 Flash subdev. */ + ret = v4l2_flash_init(flash, + &v4l2_flash_config, + led_get_v4l2_flash_ops(), + &led->v4l2_flash); + if (ret < 0) + goto error_v4l2_flash_init; + + return ret; + +error_v4l2_flash_init: + led_classdev_flash_unregister(flash); +error_gpio_en_set: + if (gpio_is_valid(enset_gpio)) + gpio_free(enset_gpio); +error_gpio_flen: + if (gpio_is_valid(flen_gpio)) + gpio_free(flen_gpio); + mutex_destroy(&led->lock); + + return ret; +} + +static int aat1290_led_remove(struct platform_device *pdev) +{ + struct aat1290_led *led = platform_get_drvdata(pdev); + + v4l2_flash_release(led->v4l2_flash); + led_classdev_flash_unregister(&led->ldev); + cancel_work_sync(&led->work_brightness_set); + + if (gpio_is_valid(led->en_set_gpio)) + gpio_free(led->en_set_gpio); + if (gpio_is_valid(led->flen_gpio)) + gpio_free(led->flen_gpio); + + mutex_destroy(&led->lock); + + return 0; +} + +static struct of_device_id aat1290_led_dt_match[] = { + {.compatible = "skyworks,aat1290"}, + {}, +}; + +static struct platform_driver aat1290_led_driver = { + .probe = aat1290_led_probe, + .remove = aat1290_led_remove, + .driver = { + .name = "aat1290-led", + .owner = THIS_MODULE, + .of_match_table = aat1290_led_dt_match, + }, +}; + +module_platform_driver(aat1290_led_driver); + +MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>"); +MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs"); +MODULE_LICENSE("GPL"); -- 1.7.9.5 -- 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