From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jacek Anaszewski Subject: [PATCH v1 03/11] leds: Add driver for AAT1290 current regulator Date: Fri, 20 Mar 2015 16:03:23 +0100 Message-ID: <1426863811-12516-4-git-send-email-j.anaszewski@samsung.com> References: <1426863811-12516-1-git-send-email-j.anaszewski@samsung.com> Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:16063 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751203AbbCTPD6 (ORCPT ); Fri, 20 Mar 2015 11:03:58 -0400 In-reply-to: <1426863811-12516-1-git-send-email-j.anaszewski@samsung.com> Sender: linux-leds-owner@vger.kernel.org List-Id: linux-leds@vger.kernel.org To: linux-leds@vger.kernel.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org Cc: kyungmin.park@samsung.com, pavel@ucw.cz, cooloney@gmail.com, rpurdie@rpsys.net, sakari.ailus@iki.fi, s.nawrocki@samsung.com, Jacek Anaszewski 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 Acked-by: Kyungmin Park Cc: Bryan Wu Cc: Richard Purdie --- drivers/leds/Kconfig | 8 + drivers/leds/Makefile | 1 + drivers/leds/leds-aat1290.c | 382 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 391 insertions(+) create mode 100644 drivers/leds/leds-aat1290.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index f9fbeb5..c3b5b027 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -42,6 +42,14 @@ 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 + depends on GPIOLIB + depends on OF + help + This option enables support for the LEDs on the AAT1290. + config LEDS_LM3530 tristate "LCD Backlight driver for LM3530" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 9413fdb..0b3fd0e 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -7,6 +7,7 @@ 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_BD2802) += leds-bd2802.o obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c new file mode 100644 index 0000000..456f9a9d --- /dev/null +++ b/drivers/leds/leds-aat1290.c @@ -0,0 +1,382 @@ +/* + * LED Flash class driver for the AAT1290 + * 1.5A Step-Up Current Regulator for Flash LEDs + * + * Copyright (C) 2015, Samsung Electronics Co., Ltd. + * Author: Jacek Anaszewski + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17 +#define AAT1290_MAX_MM_CURR_PERCENT_0 16 +#define AAT1290_MAX_MM_CURR_PERCENT_100 1 + +#define AAT1290_FLASH_SAFETY_TIMER_ADDR 18 + +#define AAT1290_MOVIE_MODE_CONFIG_ADDR 19 +#define AAT1290_MOVIE_MODE_OFF 1 +#define AAT1290_MOVIE_MODE_ON 3 + +#define AAT1290_MM_CURRENT_RATIO_ADDR 20 +#define AAT1290_MM_TO_FL_1_92 1 + +#define AAT1290_MM_TO_FL_RATIO 1000 / 1920 +#define AAT1290_MAX_MM_CURRENT(fl_max) (fl_max * AAT1290_MM_TO_FL_RATIO) + +#define AAT1290_LATCH_TIME_MIN_US 500 +#define AAT1290_LATCH_TIME_MAX_US 1000 +#define AAT1290_EN_SET_TICK_TIME_US 1 +#define AAT1290_FLEN_OFF_DELAY_TIME_US 10 +#define AAT1290_FLASH_TM_NUM_LEVELS 16 +#define AAT1290_MM_CURRENT_SCALE_SIZE 15 + +#define AAT1290_NAME "aat1290" + + +struct aat1290_led_settings { + struct led_flash_setting torch_brightness; + struct led_flash_setting flash_timeout; +}; + +struct aat1290_led { + /* platform device data */ + struct platform_device *pdev; + /* secures access to the device */ + struct mutex lock; + + /* related LED Flash class device */ + struct led_classdev_flash fled_cdev; + + /* FLEN pin */ + struct gpio_desc *gpio_fl_en; + /* EN|SET pin */ + struct gpio_desc *gpio_en_set; + + /* maximum flash timeout */ + u32 max_flash_tm; + /* maximum LED current in flash mode */ + u32 max_flash_current; + /* device mode */ + bool movie_mode; + + /* brightness cache */ + unsigned int torch_brightness; + /* assures led-triggers compatibility */ + struct work_struct work_brightness_set; +}; + +static struct aat1290_led *fled_cdev_to_led( + struct led_classdev_flash *fled_cdev) +{ + return container_of(fled_cdev, struct aat1290_led, fled_cdev); +} + +static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value) +{ + int i; + + gpiod_direction_output(led->gpio_fl_en, 0); + gpiod_direction_output(led->gpio_en_set, 0); + + udelay(AAT1290_FLEN_OFF_DELAY_TIME_US); + + /* write address */ + for (i = 0; i < addr; ++i) { + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpiod_direction_output(led->gpio_en_set, 0); + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpiod_direction_output(led->gpio_en_set, 1); + } + + usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US); + + /* write data */ + for (i = 0; i < value; ++i) { + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpiod_direction_output(led->gpio_en_set, 0); + udelay(AAT1290_EN_SET_TICK_TIME_US); + gpiod_direction_output(led->gpio_en_set, 1); + } + + usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US); +} + +static void aat1290_set_flash_safety_timer(struct aat1290_led *led, + unsigned int micro_sec) +{ + struct led_classdev_flash *fled_cdev = &led->fled_cdev; + struct led_flash_setting *flash_tm = &fled_cdev->timeout; + int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS - + (micro_sec / flash_tm->step) + 1; + + aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR, + flash_tm_reg); +} + +static void aat1290_brightness_set(struct aat1290_led *led, + enum led_brightness brightness) +{ + mutex_lock(&led->lock); + + if (brightness == 0) { + gpiod_direction_output(led->gpio_fl_en, 0); + gpiod_direction_output(led->gpio_en_set, 0); + led->movie_mode = false; + 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 *fled_cdev = lcdev_to_flcdev(led_cdev); + struct aat1290_led *led = fled_cdev_to_led(fled_cdev); + + led->torch_brightness = brightness; + schedule_work(&led->work_brightness_set); +} + +static int aat1290_led_brightness_set_sync(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); + struct aat1290_led *led = fled_cdev_to_led(fled_cdev); + + aat1290_brightness_set(led, brightness); + + return 0; +} + +static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev, + bool state) + +{ + struct aat1290_led *led = fled_cdev_to_led(fled_cdev); + struct led_classdev *led_cdev = &fled_cdev->led_cdev; + struct led_flash_setting *timeout = &fled_cdev->timeout; + + mutex_lock(&led->lock); + + if (state == 0) { + gpiod_direction_output(led->gpio_fl_en, 0); + gpiod_direction_output(led->gpio_en_set, 0); + goto done; + } + + aat1290_set_flash_safety_timer(led, timeout->val); + + gpiod_direction_output(led->gpio_fl_en, 1); + +done: + /* + * 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 and movie_mode properties needs + * to be updated here to reflect the actual state. + */ + led_cdev->brightness = 0; + led->movie_mode = false; + + mutex_unlock(&led->lock); + + return 0; +} + +static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev, + 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 led_classdev *led_cdev = &led->fled_cdev.led_cdev; + struct device *dev = &led->pdev->dev; + struct device_node *child_node; + int ret = 0; + + led->gpio_fl_en = devm_gpiod_get(dev, "flen"); + if (IS_ERR(led->gpio_fl_en)) { + ret = PTR_ERR(led->gpio_fl_en); + dev_err(dev, "Unable to claim gpio \"flen\".\n"); + return ret; + } + + led->gpio_en_set = devm_gpiod_get(dev, "enset"); + if (IS_ERR(led->gpio_en_set)) { + ret = PTR_ERR(led->gpio_en_set); + dev_err(dev, "Unable to claim gpio \"enset\".\n"); + return ret; + } + + child_node = of_get_next_available_child(dev->of_node, NULL); + if (!child_node) { + dev_err(dev, "No DT child node found for connected LED.\n"); + return -EINVAL; + } + + of_property_read_string(child_node, "label", + (const char **) &led_cdev->name); + + ret = of_property_read_u32(child_node, "flash-max-microamp", + &led->max_flash_current); + if (ret < 0) { + dev_err(dev, + "Error reading \"flash-max-microamp\" DT property\n"); + return ret; + } + + ret = of_property_read_u32(child_node, "flash-timeout-us", + &led->max_flash_tm); + if (ret < 0) { + dev_err(dev, + "Error reading \"flash-timeout-us\" DT property\n"); + 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 timeout setting */ + setting = &s->flash_timeout; + setting->min = led->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS; + setting->max = setting->min * AAT1290_FLASH_TM_NUM_LEVELS; + setting->step = setting->min; + setting->val = setting->max; +} + +static 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 aat1290_led *led; + struct led_classdev *led_cdev; + struct led_classdev_flash *fled_cdev; + struct aat1290_led_settings settings; + int ret; + + led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + + led->pdev = pdev; + platform_set_drvdata(pdev, led); + + fled_cdev = &led->fled_cdev; + led_cdev = &fled_cdev->led_cdev; + + ret = aat1290_led_parse_dt(led); + if (ret < 0) + return ret; + + if (!led_cdev->name) + led_cdev->name = AAT1290_NAME; + + /* Init flash settings */ + aat1290_init_flash_settings(led, &settings); + + fled_cdev->timeout = settings.flash_timeout; + fled_cdev->ops = &flash_ops; + + /* Init LED class */ + led_cdev->brightness_set = aat1290_led_brightness_set; + led_cdev->brightness_set_sync = aat1290_led_brightness_set_sync; + led_cdev->max_brightness = AAT1290_MM_CURRENT_SCALE_SIZE; + led_cdev->flags |= LED_DEV_CAP_FLASH; + + INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work); + + /* Register in the LED subsystem. */ + ret = led_classdev_flash_register(&pdev->dev, fled_cdev); + if (ret < 0) + return ret; + + mutex_init(&led->lock); + + return 0; +} + +static int aat1290_led_remove(struct platform_device *pdev) +{ + struct aat1290_led *led = platform_get_drvdata(pdev); + + led_classdev_flash_unregister(&led->fled_cdev); + cancel_work_sync(&led->work_brightness_set); + + mutex_destroy(&led->lock); + + return 0; +} + +static const 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", + .owner = THIS_MODULE, + .of_match_table = aat1290_led_dt_match, + }, +}; + +module_platform_driver(aat1290_led_driver); + +MODULE_AUTHOR("Jacek Anaszewski "); +MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs"); +MODULE_LICENSE("GPL v2"); -- 1.7.9.5