Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755051AbbDJILw (ORCPT ); Fri, 10 Apr 2015 04:11:52 -0400 Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:43410 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754422AbbDJILo (ORCPT ); Fri, 10 Apr 2015 04:11:44 -0400 Date: Fri, 10 Apr 2015 11:11:06 +0300 From: Sakari Ailus To: Ingi Kim Cc: cooloney@gmail.com, rpurdie@rpsys.net, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, j.anaszewski@samsung.com, varkabhadram@gmail.com, joe@perches.com, sw0312.kim@samsung.com, cw00.choi@samsung.com, jh80.chung@samsung.com, ideal.song@samsung.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org Subject: Re: [PATCH v6 3/3] leds: Add ktd2692 flash LED driver Message-ID: <20150410081106.GF20756@valkosipuli.retiisi.org.uk> References: <1428648359-23289-1-git-send-email-ingi2.kim@samsung.com> <1428648359-23289-4-git-send-email-ingi2.kim@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1428648359-23289-4-git-send-email-ingi2.kim@samsung.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 14961 Lines: 484 Hi Ingi, Thanks for the update. Just a few comments below. Let's also wait for the final agreement on the limit properties, hopefully we have that soon. On Fri, Apr 10, 2015 at 03:45:59PM +0900, Ingi Kim wrote: > This patch adds a driver to support the ktd2692 flash LEDs. > ktd2692 can control flash current by ExpressWire interface. > > Signed-off-by: Ingi Kim > --- > drivers/leds/Kconfig | 9 + > drivers/leds/Makefile | 1 + > drivers/leds/leds-ktd2692.c | 408 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 418 insertions(+) > create mode 100644 drivers/leds/leds-ktd2692.c > > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig > index 51059bb..86197ef 100644 > --- a/drivers/leds/Kconfig > +++ b/drivers/leds/Kconfig > @@ -505,6 +505,15 @@ config LEDS_MENF21BMC > This driver can also be built as a module. If so the module > will be called leds-menf21bmc. > > +config LEDS_KTD2692 > + tristate "KTD2692 LED flash support" > + depends on LEDS_CLASS_FLASH && GPIOLIB > + help > + This option enables support for KTD2692 LED flash connected > + through ExpressWire interface. > + > + Say Y to enable this driver. > + > comment "LED driver for blink(1) USB RGB LED is under Special HID drivers (HID_THINGM)" > > config LEDS_BLINKM > diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile > index a739ae2..ed5ed79 100644 > --- a/drivers/leds/Makefile > +++ b/drivers/leds/Makefile > @@ -59,6 +59,7 @@ obj-$(CONFIG_LEDS_BLINKM) += leds-blinkm.o > obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o > obj-$(CONFIG_LEDS_VERSATILE) += leds-versatile.o > obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o > +obj-$(CONFIG_LEDS_KTD2692) += leds-ktd2692.o > > # LED SPI Drivers > obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o > diff --git a/drivers/leds/leds-ktd2692.c b/drivers/leds/leds-ktd2692.c > new file mode 100644 > index 0000000..a9e4862 > --- /dev/null > +++ b/drivers/leds/leds-ktd2692.c > @@ -0,0 +1,408 @@ > +/* > + * LED driver : leds-ktd2692.c > + * > + * Copyright (C) 2015 Samsung Electronics > + * Ingi Kim > + * > + * 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 Shouldn't this be linux/of.h? > +#include > +#include > +#include > + > +/* Value related the flash mode */ > +#define KTD2692_FLASH_MODE_TIMEOUT_LEVELS 8 > +#define KTD2692_FLASH_MODE_TIMEOUT_DISABLE 0 > +#define KTD2692_FLASH_MODE_TIMEOUT_DEFAULT_US 1049000 > +#define KTD2692_FLASH_MODE_TIMEOUT_MAX_US 1835000 > +#define KTD2692_FLASH_MODE_CURR_PERCENT(x) (((x) * 16) / 100) > + > +/* Macro for getting offset of flash timeout */ > +#define GET_TIMEOUT_OFFSET(timeout, step) ((timeout) / (step)) > + > +/* Adjust a multiple of brightness */ > +#define KTD2692_BRIGHTNESS_RANGE_255_TO_16(x) (((x) >> 4) & 0x0F) > +#define KTD2692_BRIGHTNESS_RANGE_255_TO_8(x) (((x) >> 5) & 0x0F) > +#define KTD2692_BRIGHTNESS_RANGE_255_TO_4(x) (((x) >> 6) & 0x0F) > + > +/* Base register address */ > +#define KTD2692_REG_LVP_BASE 0x00 > +#define KTD2692_REG_FLASH_TIMEOUT_BASE 0x20 > +#define KTD2692_REG_MIN_CURRENT_SET_BASE 0x40 > +#define KTD2692_REG_MOVIE_CURRENT_BASE 0x60 > +#define KTD2692_REG_FLASH_CURRENT_BASE 0x80 > +#define KTD2692_REG_MODE_BASE 0xA0 > + > +/* Set bit coding time for expresswire interface */ > +#define KTD2692_TIME_RESET_US 700 > +#define KTD2692_TIME_DATA_START_TIME_US 10 > +#define KTD2692_TIME_HIGH_END_OF_DATA_US 350 > +#define KTD2692_TIME_LOW_END_OF_DATA_US 10 > +#define KTD2692_TIME_SHORT_BITSET_US 4 > +#define KTD2692_TIME_LONG_BITSET_US 12 > + > +/* KTD2692 default length of name */ > +#define KTD2692_NAME_LENGTH 20 > + > +enum ktd2692_bitset { > + KTD2692_LOW = 0, > + KTD2692_HIGH, > +}; > + > +/* Movie / Flash Mode Control */ > +enum ktd2692_led_mode { > + KTD2692_MODE_DISABLE = 0, /* default */ > + KTD2692_MODE_MOVIE, > + KTD2692_MODE_FLASH, > +}; > + > +struct ktd2692_context { > + /* Related LED Flash class device */ > + struct led_classdev_flash fled_cdev; > + > + struct mutex lock; > + struct regulator *regulator; > + struct work_struct work_brightness_set; > + > + int aux_gpio; > + int ctrl_gpio; > + > + enum ktd2692_led_mode mode; > + enum led_brightness torch_brightness; > +}; > + > +static struct ktd2692_context *fled_cdev_to_led( > + struct led_classdev_flash *fled_cdev) > +{ > + return container_of(fled_cdev, struct ktd2692_context, fled_cdev); > +} > + > +static void ktd2692_expresswire_start(struct ktd2692_context *led) > +{ > + gpio_set_value(led->ctrl_gpio, KTD2692_HIGH); > + udelay(KTD2692_TIME_DATA_START_TIME_US); > +} > + > +static void ktd2692_expresswire_reset(struct ktd2692_context *led) > +{ > + gpio_set_value(led->ctrl_gpio, KTD2692_LOW); > + udelay(KTD2692_TIME_RESET_US); > +} > + > +static void ktd2692_expresswire_end(struct ktd2692_context *led) > +{ > + gpio_set_value(led->ctrl_gpio, KTD2692_LOW); > + udelay(KTD2692_TIME_LOW_END_OF_DATA_US); > + gpio_set_value(led->ctrl_gpio, KTD2692_HIGH); > + udelay(KTD2692_TIME_HIGH_END_OF_DATA_US); > +} > + > +static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit) > +{ > + /* > + * The Low Bit(0) and High Bit(1) is based on a time detection > + * algorithm between time low and time high > + * Time_(L_LB) : Low time of the Low Bit(0) > + * Time_(H_LB) : High time of the LOW Bit(0) > + * Time_(L_HB) : Low time of the High Bit(1) > + * Time_(H_HB) : High time of the High Bit(1) > + * > + * It can be simplified to: > + * Low Bit(0) : 2 * Time_(H_LB) < Time_(L_LB) > + * High Bit(1) : 2 * Time_(L_HB) < Time_(H_HB) > + * HIGH ___ ____ _.. _________ ___ > + * |_________| |_.. |____| |__| > + * LOW > + * [ Low Bit (0) ] [ High Bit(1) ] > + */ > + if (bit) { > + gpio_set_value(led->ctrl_gpio, KTD2692_LOW); > + udelay(KTD2692_TIME_SHORT_BITSET_US); > + gpio_set_value(led->ctrl_gpio, KTD2692_HIGH); > + udelay(KTD2692_TIME_LONG_BITSET_US); > + } else { > + gpio_set_value(led->ctrl_gpio, KTD2692_LOW); > + udelay(KTD2692_TIME_LONG_BITSET_US); > + gpio_set_value(led->ctrl_gpio, KTD2692_HIGH); > + udelay(KTD2692_TIME_SHORT_BITSET_US); > + } > +} > + > +static void ktd2692_expresswire_write(struct ktd2692_context *led, u8 value) > +{ > + int i; > + > + ktd2692_expresswire_start(led); > + for (i = 7; i >= 0; i--) > + ktd2692_expresswire_set_bit(led, value & BIT(i)); > + ktd2692_expresswire_end(led); > +} > + > +static void ktd2692_brightness_set(struct ktd2692_context *led, > + enum led_brightness brightness) > +{ > + mutex_lock(&led->lock); > + > + if (brightness == LED_OFF) { > + led->mode = KTD2692_MODE_DISABLE; > + gpio_set_value(led->aux_gpio, KTD2692_LOW); > + } else { > + ktd2692_expresswire_write(led, KTD2692_REG_MOVIE_CURRENT_BASE | > + KTD2692_BRIGHTNESS_RANGE_255_TO_8(brightness)); > + led->mode = KTD2692_MODE_MOVIE; > + } > + > + ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE); > + mutex_unlock(&led->lock); > +} > + > +static void ktd2692_brightness_set_work(struct work_struct *work) > +{ > + struct ktd2692_context *led = > + container_of(work, struct ktd2692_context, work_brightness_set); > + > + ktd2692_brightness_set(led, led->torch_brightness); > +} > + > +static void ktd2692_led_brightness_set(struct led_classdev *led_cdev, > + enum led_brightness brightness) > +{ > + struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); > + struct ktd2692_context *led = fled_cdev_to_led(fled_cdev); > + > + led->torch_brightness = brightness; > + schedule_work(&led->work_brightness_set); > +} > + > +static int ktd2692_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 ktd2692_context *led = fled_cdev_to_led(fled_cdev); > + > + ktd2692_brightness_set(led, brightness); > + > + return 0; > +} > + > +static int ktd2692_led_flash_strobe_set(struct led_classdev_flash *fled_cdev, > + bool state) > +{ > + struct ktd2692_context *led = fled_cdev_to_led(fled_cdev); > + struct led_flash_setting *timeout = &fled_cdev->timeout; > + u32 flash_tm_reg; > + > + mutex_lock(&led->lock); > + > + if (state == 0) { > + led->mode = KTD2692_MODE_DISABLE; > + gpio_set_value(led->aux_gpio, KTD2692_LOW); > + } else { > + flash_tm_reg = GET_TIMEOUT_OFFSET(timeout->val, timeout->step); > + ktd2692_expresswire_write(led, flash_tm_reg > + | KTD2692_REG_FLASH_TIMEOUT_BASE); > + > + led->mode = KTD2692_MODE_FLASH; > + gpio_set_value(led->aux_gpio, KTD2692_HIGH); > + } > + > + ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE); > + > + fled_cdev->led_cdev.brightness = LED_OFF; > + led->mode = KTD2692_MODE_DISABLE; > + > + mutex_unlock(&led->lock); > + > + return 0; > +} > + > +static int ktd2692_led_flash_timeout_set(struct led_classdev_flash *fled_cdev, > + u32 timeout) > +{ > + return 0; > +} > + > +static void ktd2692_init_flash_timeout(u32 flash_timeout_us, > + struct led_flash_setting *setting) > +{ > + setting->min = KTD2692_FLASH_MODE_TIMEOUT_DISABLE; > + setting->max = KTD2692_FLASH_MODE_TIMEOUT_MAX_US; > + setting->step = KTD2692_FLASH_MODE_TIMEOUT_MAX_US > + / (KTD2692_FLASH_MODE_TIMEOUT_LEVELS - 1); > + setting->val = flash_timeout_us; > +} > + > +static void ktd2692_setup(struct ktd2692_context *led) > +{ > + led->mode = KTD2692_MODE_DISABLE; > + ktd2692_expresswire_reset(led); > + gpio_set_value(led->aux_gpio, KTD2692_LOW); > + > + ktd2692_expresswire_write(led, KTD2692_FLASH_MODE_CURR_PERCENT(45) > + | KTD2692_REG_FLASH_CURRENT_BASE); > +} > + > +static int ktd2692_parse_dt(struct ktd2692_context *led, struct device *dev, > + u32 *flash_timeout_us) > +{ > + struct device_node *np = dev->of_node; > + struct device_node *child_node; > + int ret; > + > + if (!dev->of_node) > + return -ENXIO; > + > + led->ctrl_gpio = of_get_named_gpio(np, "ctrl-gpio", 0); > + if (!gpio_is_valid(led->ctrl_gpio)) { > + dev_err(dev, "no ctrl-gpio property found\n"); > + return -EINVAL; > + } > + > + led->aux_gpio = of_get_named_gpio(np, "aux-gpio", 0); > + if (!gpio_is_valid(led->aux_gpio)) { > + dev_err(dev, "no aux-gpio property found\n"); > + return -EINVAL; > + } > + > + ret = devm_gpio_request_one(dev, led->ctrl_gpio, > + GPIOF_OPEN_SOURCE, "ctrl-gpio"); I think you could simply use devm_gpio_get(), and start using the new API instead. It'd save quite a few lines of code, too. > + if (ret) { > + dev_err(dev, "failed to request ctrl-gpio %d error %d\n", > + led->ctrl_gpio, ret); > + return ret; > + } > + > + ret = devm_gpio_request_one(dev, led->aux_gpio, > + GPIOF_OPEN_SOURCE, "aux-gpio"); > + if (ret) { > + dev_err(dev, "failed to request aux-gpio %d error %d\n", > + led->aux_gpio, ret); > + return ret; > + } > + > + child_node = of_get_next_available_child(np, NULL); > + if (!child_node) { > + dev_err(dev, "No DT child node found for connected LED.\n"); > + return -EINVAL; > + } > + > + led->fled_cdev.led_cdev.name = > + of_get_property(child_node, "label", NULL) ? : child_node->name; > + > + ret = of_property_read_u32(child_node, > + "flash-timeout-us", flash_timeout_us); You should do of_node_put(child_node) once you no longer need it. > + /* default setting */ > + if (ret) > + *flash_timeout_us = KTD2692_FLASH_MODE_TIMEOUT_DEFAULT_US; > + > + return 0; > +} > + > +static const struct led_flash_ops flash_ops = { > + .strobe_set = ktd2692_led_flash_strobe_set, > + .timeout_set = ktd2692_led_flash_timeout_set, > +}; > + > +static int ktd2692_probe(struct platform_device *pdev) > +{ > + struct ktd2692_context *led; > + struct led_classdev *led_cdev; > + struct led_classdev_flash *fled_cdev; > + struct led_flash_setting flash_timeout; > + u32 flash_timeout_us; > + int ret; > + > + led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL); > + if (!led) > + return -ENOMEM; > + > + fled_cdev = &led->fled_cdev; > + led_cdev = &fled_cdev->led_cdev; > + > + ret = ktd2692_parse_dt(led, &pdev->dev, &flash_timeout_us); > + if (ret) > + return ret; > + > + led->regulator = devm_regulator_get(&pdev->dev, "vin"); > + if (IS_ERR(led->regulator)) { > + dev_err(&pdev->dev, "regulator get failed\n"); > + return PTR_ERR(led->regulator); > + } > + > + ret = regulator_enable(led->regulator); > + if (ret) { > + dev_err(&pdev->dev, "Failed to enable supply: %d\n", ret); > + return ret; > + } > + > + ktd2692_init_flash_timeout(flash_timeout_us, &flash_timeout); > + > + fled_cdev->timeout = flash_timeout; > + fled_cdev->ops = &flash_ops; > + > + led_cdev->brightness_set = ktd2692_led_brightness_set; > + led_cdev->brightness_set_sync = ktd2692_led_brightness_set_sync; > + led_cdev->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; > + > + mutex_init(&led->lock); > + INIT_WORK(&led->work_brightness_set, ktd2692_brightness_set_work); > + > + platform_set_drvdata(pdev, led); > + > + ret = led_classdev_flash_register(&pdev->dev, fled_cdev); > + if (ret) { > + dev_err(&pdev->dev, "can't register LED %s\n", led_cdev->name); > + mutex_destroy(&led->lock); > + return ret; > + } > + > + ktd2692_setup(led); > + > + return 0; > +} > + > +static int ktd2692_remove(struct platform_device *pdev) > +{ > + struct ktd2692_context *led = platform_get_drvdata(pdev); > + int ret; > + > + led_classdev_flash_unregister(&led->fled_cdev); > + cancel_work_sync(&led->work_brightness_set); > + > + ret = regulator_disable(led->regulator); > + if (ret) > + dev_err(&pdev->dev, "Failed to disable supply: %d\n", ret); > + > + mutex_destroy(&led->lock); > + > + return 0; > +} > + > +static const struct of_device_id ktd2692_match[] = { > + { .compatible = "kinetic,ktd2692", }, > + { /* sentinel */ }, > +}; > + > +static struct platform_driver ktd2692_driver = { > + .driver = { > + .name = "ktd2692", > + .of_match_table = ktd2692_match, > + }, > + .probe = ktd2692_probe, > + .remove = ktd2692_remove, > +}; > + > +module_platform_driver(ktd2692_driver); > + > +MODULE_AUTHOR("Ingi Kim "); > +MODULE_DESCRIPTION("Kinetic KTD2692 LED driver"); > +MODULE_LICENSE("GPL v2"); -- Kind regards, Sakari Ailus e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/