From patchwork Thu Feb 27 18:50:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Weiss X-Patchwork-Id: 209155 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80480C35DF9 for ; Thu, 27 Feb 2020 19:18:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 507E424680 for ; Thu, 27 Feb 2020 19:18:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=z3ntu.xyz header.i=@z3ntu.xyz header.b="AAE2+wUx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729545AbgB0TSU (ORCPT ); Thu, 27 Feb 2020 14:18:20 -0500 Received: from mail.z3ntu.xyz ([128.199.32.197]:51496 "EHLO mail.z3ntu.xyz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729418AbgB0TST (ORCPT ); Thu, 27 Feb 2020 14:18:19 -0500 X-Greylist: delayed 319 seconds by postgrey-1.27 at vger.kernel.org; Thu, 27 Feb 2020 14:18:17 EST Received: from localhost.localdomain (80-110-126-226.cgn.dynamic.surfer.at [80.110.126.226]) by mail.z3ntu.xyz (Postfix) with ESMTPSA id 4C186C2E6A; Thu, 27 Feb 2020 19:12:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=z3ntu.xyz; s=z3ntu; t=1582830775; bh=Y/pmKEy6mbtQ9MTu4C5WRO85Y36YOBMP53cw8i6LEMw=; h=From:To:Cc:Subject:Date; b=AAE2+wUxPm7bqokJXZtsH3ivLMlJvxVtUMR3pTaMn/472pkS24BDjnuINAJsbo5fx 5mE/yaMC9dtIfBOfTD6a5HZdDRQZCR01qK26UQgzQNKh/olOTJWOwtksJPN98qOflD UddF9PdCWrJjaDBx65wuOLy846W1QBTz2trqtqlE= From: Luca Weiss To: linux-leds@vger.kernel.org Cc: ~postmarketos/upstreaming@lists.sr.ht, Luca Weiss , Jacek Anaszewski , Pavel Machek , Dan Murphy , linux-kernel@vger.kernel.org Subject: [RFC PATCH] leds: add sgm3140 driver Date: Thu, 27 Feb 2020 19:50:15 +0100 Message-Id: <20200227185015.212479-1-luca@z3ntu.xyz> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Sender: linux-leds-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Add a driver for the SGMICRO SGM3140 Buck/Boost Charge Pump LED driver. This device is controller by two GPIO lines, one for enabling the LED and the second one for switching between torch and flash mode. The device will automatically switch to torch mode after being in flash mode for about 250-300ms, so after that time the driver will turn the LED off again automatically. Signed-off-by: Luca Weiss --- Hi, this driver is controllable via sysfs and v4l2 APIs (as documented in Documentation/leds/leds-class-flash.rst). The following is possible: # Torch on echo 1 > /sys/class/leds/white\:flash/brightness # Torch off echo 0 > /sys/class/leds/white\:flash/brightness # Activate flash echo 1 > /sys/class/leds/white\:flash/flash_strobe # Torch on v4l2-ctl -d /dev/video1 -c led_mode=2 # Torch off v4l2-ctl -d /dev/video1 -c led_mode=0 # Activate flash v4l2-ctl -d /dev/video1 -c strobe=1 Unfortunately the last command (enabling the 'flash' via v4l2 results in the following being printed and nothing happening: VIDIOC_S_EXT_CTRLS: failed: Resource busy strobe: Resource busy Unfortunately I couldn't figure out the reason so I'm hoping to get some guidance for this. iirc it worked at some point but then stopped. I will also write dt bindings for the driver once I have "strobe" working. Regards, Luca drivers/leds/Kconfig | 9 ++ drivers/leds/Makefile | 1 + drivers/leds/leds-sgm3140.c | 210 ++++++++++++++++++++++++++++++++++++ 3 files changed, 220 insertions(+) create mode 100644 drivers/leds/leds-sgm3140.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 4b68520ac251..7c391af8b380 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -836,6 +836,15 @@ config LEDS_LM36274 Say Y to enable the LM36274 LED driver for TI LMU devices. This supports the LED device LM36274. +config LEDS_SGM3140 + tristate "LED support for the SGM3140" + depends on LEDS_CLASS_FLASH + depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS + depends on OF + help + This option enables support for the SGM3140 500mA Buck/Boost Charge + Pump LED Driver. It has supports flash and torch mode. + comment "LED Triggers" source "drivers/leds/trigger/Kconfig" diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 2da39e896ce8..38d57dd53e4b 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -85,6 +85,7 @@ obj-$(CONFIG_LEDS_LM3601X) += leds-lm3601x.o obj-$(CONFIG_LEDS_TI_LMU_COMMON) += leds-ti-lmu-common.o obj-$(CONFIG_LEDS_LM3697) += leds-lm3697.o obj-$(CONFIG_LEDS_LM36274) += leds-lm36274.o +obj-$(CONFIG_LEDS_SGM3140) += leds-sgm3140.o # LED SPI Drivers obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o diff --git a/drivers/leds/leds-sgm3140.c b/drivers/leds/leds-sgm3140.c new file mode 100644 index 000000000000..9e91392f0343 --- /dev/null +++ b/drivers/leds/leds-sgm3140.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 Luca Weiss + +#include +#include +#include +#include +#include + +#include + +#define SGM3140_NAME "sgm3140" + +struct sgm3140 { + struct gpio_desc *flash_gpio; + struct gpio_desc *enable_gpio; + + struct led_classdev_flash fled_cdev; + struct v4l2_flash *v4l2_flash; + + struct timer_list powerdown_timer; +}; + +static struct sgm3140 *flcdev_to_sgm3140(struct led_classdev_flash *flcdev) +{ + return container_of(flcdev, struct sgm3140, fled_cdev); +} + +int sgm3140_strobe_set(struct led_classdev_flash *fled_cdev, bool state) +{ + struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev); + + if (state) { + gpiod_set_value_cansleep(priv->flash_gpio, 1); + gpiod_set_value_cansleep(priv->enable_gpio, 1); + mod_timer(&priv->powerdown_timer, + jiffies + msecs_to_jiffies(250)); + } else { + gpiod_set_value_cansleep(priv->enable_gpio, 0); + gpiod_set_value_cansleep(priv->flash_gpio, 0); + del_timer_sync(&priv->powerdown_timer); + } + + return 0; +} + +struct led_flash_ops sgm3140_flash_ops = { + .strobe_set = sgm3140_strobe_set, +}; + +int sgm3140_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); + struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev); + + if (brightness == LED_OFF) + gpiod_set_value_cansleep(priv->enable_gpio, 0); + else + gpiod_set_value_cansleep(priv->enable_gpio, 1); + + return 0; +} + +static void sgm3140_powerdown_timer(struct timer_list *t) +{ + struct sgm3140 *priv = from_timer(priv, t, powerdown_timer); + + gpiod_set_value_cansleep(priv->enable_gpio, 0); + gpiod_set_value_cansleep(priv->flash_gpio, 0); +} + +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS) +static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv, + struct v4l2_flash_config *v4l2_sd_cfg) +{ + struct led_classdev *led_cdev = &priv->fled_cdev.led_cdev; + struct led_flash_setting *s; + + strlcpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name, + sizeof(v4l2_sd_cfg->dev_name)); + + s = &v4l2_sd_cfg->intensity; + s->min = 0; + s->max = 1; + s->step = 1; + s->val = 1; +} + +#else +static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv, + struct v4l2_flash_config *v4l2_sd_cfg) +{ +} +#endif + +static int sgm3140_probe(struct platform_device *pdev) +{ + struct sgm3140 *priv; + struct led_classdev *led_cdev; + struct led_classdev_flash *fled_cdev; + struct led_init_data init_data = {}; + struct device_node *child_node; + struct v4l2_flash_config v4l2_sd_cfg; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->flash_gpio = devm_gpiod_get(&pdev->dev, "flash", GPIOD_OUT_LOW); + ret = PTR_ERR_OR_ZERO(priv->flash_gpio); + if (ret) { + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "Failed to request flash gpio: %d\n", + ret); + return ret; + } + + priv->enable_gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW); + ret = PTR_ERR_OR_ZERO(priv->enable_gpio); + if (ret) { + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "Failed to request enable gpio: %d\n", + ret); + return ret; + } + + child_node = of_get_next_available_child(pdev->dev.of_node, NULL); + if (!child_node) { + dev_err(&pdev->dev, "No DT child node found for connected LED.\n"); + return -EINVAL; + } + + timer_setup(&priv->powerdown_timer, sgm3140_powerdown_timer, 0); + + fled_cdev = &priv->fled_cdev; + led_cdev = &fled_cdev->led_cdev; + + fled_cdev->ops = &sgm3140_flash_ops; + + led_cdev->brightness_set_blocking = sgm3140_brightness_set; + led_cdev->max_brightness = LED_ON; + led_cdev->flags |= LED_DEV_CAP_FLASH; + + init_data.fwnode = of_fwnode_handle(child_node); + init_data.devicename = SGM3140_NAME; + + platform_set_drvdata(pdev, priv); + + /* Register in the LED subsystem */ + ret = led_classdev_flash_register_ext(&pdev->dev, fled_cdev, &init_data); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register flash device: %d\n", + ret); + goto err_flash_register; + } + + sgm3140_init_v4l2_flash_config(priv, &v4l2_sd_cfg); + + /* Create V4L2 Flash subdev */ + priv->v4l2_flash = v4l2_flash_init(&pdev->dev, of_fwnode_handle(child_node), + fled_cdev, NULL, + &v4l2_sd_cfg); + if (IS_ERR(priv->v4l2_flash)) { + ret = PTR_ERR(priv->v4l2_flash); + goto err_v4l2_flash_init; + } + + return 0; + +err_v4l2_flash_init: + led_classdev_flash_unregister(fled_cdev); +err_flash_register: + of_node_put(child_node); + return ret; +} + +static int sgm3140_remove(struct platform_device *pdev) +{ + struct sgm3140 *priv = platform_get_drvdata(pdev); + + del_timer_sync(&priv->powerdown_timer); + + v4l2_flash_release(priv->v4l2_flash); + led_classdev_flash_unregister(&priv->fled_cdev); + + return 0; +} + +static const struct of_device_id sgm3140_dt_match[] = { + { .compatible = "sgmicro,sgm3140" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, sgm3140_dt_match); + +static struct platform_driver sgm3140_driver = { + .probe = sgm3140_probe, + .remove = sgm3140_remove, + .driver = { + .name = "sgm3140", + .of_match_table = sgm3140_dt_match, + }, +}; + +module_platform_driver(sgm3140_driver); + +MODULE_AUTHOR("Luca Weiss "); +MODULE_DESCRIPTION("SG Micro SGM3140 charge pump led driver"); +MODULE_LICENSE("GPL v2");