From patchwork Thu Apr 23 15:55:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Murphy X-Patchwork-Id: 209102 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, 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 CF152C54FCB for ; Thu, 23 Apr 2020 16:01:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABB2121582 for ; Thu, 23 Apr 2020 16:01:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="yssRXwpm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729472AbgDWQBs (ORCPT ); Thu, 23 Apr 2020 12:01:48 -0400 Received: from lelv0142.ext.ti.com ([198.47.23.249]:42392 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729282AbgDWQBs (ORCPT ); Thu, 23 Apr 2020 12:01:48 -0400 Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 03NG1i2a103829; Thu, 23 Apr 2020 11:01:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1587657704; bh=YPEbf0xj3VwNBSn88/INPsGrLSvdicS+pRqJmAtvRuY=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=yssRXwpmYGhxWpW0ExCb/jdY0KfhZQWbPEvz+cBWQwU2FIHQaiVmfAUQTo43ypVaG qzW39ELoYkzuCZQXBSnr9+LhzLUUMclEbFgKpzq14FsMvoapd4VKXVdDKw9suTi7mH 7NHgOYU5YmKbnO465MSQVwj+VKuEtncwaTDns+I0= Received: from DFLE112.ent.ti.com (dfle112.ent.ti.com [10.64.6.33]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTP id 03NG1hFL049355; Thu, 23 Apr 2020 11:01:43 -0500 Received: from DFLE101.ent.ti.com (10.64.6.22) by DFLE112.ent.ti.com (10.64.6.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Thu, 23 Apr 2020 11:01:43 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE101.ent.ti.com (10.64.6.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Thu, 23 Apr 2020 11:01:43 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 03NG1hta063402; Thu, 23 Apr 2020 11:01:43 -0500 From: Dan Murphy To: , CC: , , Dan Murphy Subject: [PATCH v20 03/17] leds: multicolor: Introduce a multicolor class definition Date: Thu, 23 Apr 2020 10:55:10 -0500 Message-ID: <20200423155524.13971-4-dmurphy@ti.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200423155524.13971-1-dmurphy@ti.com> References: <20200423155524.13971-1-dmurphy@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-leds-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Introduce a multicolor class that groups colored LEDs within a LED node. The multi color class groups monochrome LEDs and allows controlling two aspects of the final combined color: hue and lightness. The former is controlled via color_intensity file and the latter is controlled via brightness file. Signed-off-by: Dan Murphy --- v20 - Change color_ file names to multi_led, dynamically allocate the multicolor_info struct. Fixed documentation issues from Randy D. .../ABI/testing/sysfs-class-led-multicolor | 42 ++++ Documentation/leds/index.rst | 1 + Documentation/leds/leds-class-multicolor.rst | 92 ++++++++ drivers/leds/Kconfig | 10 + drivers/leds/Makefile | 1 + drivers/leds/led-class-multicolor.c | 206 ++++++++++++++++++ include/linux/led-class-multicolor.h | 121 ++++++++++ 7 files changed, 473 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor create mode 100644 Documentation/leds/leds-class-multicolor.rst create mode 100644 drivers/leds/led-class-multicolor.c create mode 100644 include/linux/led-class-multicolor.h diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor new file mode 100644 index 000000000000..ada0dbecfeab --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-led-multicolor @@ -0,0 +1,42 @@ +What: /sys/class/leds//brightness +Date: March 2020 +KernelVersion: 5.8 +Contact: Dan Murphy +Description: read/write + Writing to this file will update all LEDs within the group to a + calculated percentage of what each color LED intensity is set + to. The percentage is calculated for each grouped LED via the + equation below: + + led_brightness = brightness * multi_led_intensity/max_brightness + + For additional details please refer to + Documentation/leds/leds-class-multicolor.rst. + + The value of the color is from 0 to + /sys/class/leds//max_brightness. + +What: /sys/class/leds//multi_led_index +Date: March 2020 +KernelVersion: 5.8 +Contact: Dan Murphy +Description: read + The multi_led_index array, when read, will output the LED colors + by name as they are indexed in the multi_led_intensity file. + +What: /sys/class/leds//num_multi_leds +Date: March 2020 +KernelVersion: 5.8 +Contact: Dan Murphy +Description: read + The num_multi_leds indicates the number of LEDs defined in the + multi_led_intensity and multi_led_index files. + +What: /sys/class/leds//multi_led_intensity +Date: March 2020 +KernelVersion: 5.8 +Contact: Dan Murphy +Description: read/write + Intensity level for the LED color within the array. + The intensities for each color must be entered based on the + multi_led_index array. diff --git a/Documentation/leds/index.rst b/Documentation/leds/index.rst index 060f4e485897..bc70c6aa7138 100644 --- a/Documentation/leds/index.rst +++ b/Documentation/leds/index.rst @@ -9,6 +9,7 @@ LEDs leds-class leds-class-flash + leds-class-multicolor ledtrig-oneshot ledtrig-transient ledtrig-usbport diff --git a/Documentation/leds/leds-class-multicolor.rst b/Documentation/leds/leds-class-multicolor.rst new file mode 100644 index 000000000000..207f57e57216 --- /dev/null +++ b/Documentation/leds/leds-class-multicolor.rst @@ -0,0 +1,92 @@ +==================================== +MultiColor LED handling under Linux +==================================== + +Description +=========== +The multicolor class groups monochrome LEDs and allows controlling two +aspects of the final combined color: hue and lightness. The former is +controlled via the multi_led_intensity array file and the latter is controlled +via brightness file. + +For more details on hue and lightness notions please refer to +https://en.wikipedia.org/wiki/CIECAM02. + +Multicolor Class Control +======================== +The multicolor class presents files that groups the colors as indexes in an +array. These files are children under the LED parent node created by the +led_class framework. The led_class framework is documented in led-class.rst +within this documentation directory. + +Each colored LED will be indexed under the multi_led_* files. The order of the +colors will be arbitrary. The multi_led_index file can be read to determine the +color name to indexed value. + +The multi_led_index file is an array that contains the string list of the colors as +they are defined in each multi_led_* array file. + +The multi_led_intensity is an array that can be read or written to for the +individual color intensities. All elements within this array must be written in +order for the color LED intensities to be updated. + +The num_multi_leds file returns the total number of LEDs that are presented in +each multi_led_* array. + +Directory Layout Example +======================== +root:/sys/class/leds/multicolor:status# ls -lR +-rw-r--r-- 1 root root 4096 Oct 19 16:16 brightness +-r--r--r-- 1 root root 4096 Oct 19 16:16 multi_led_index +-rw-r--r-- 1 root root 4096 Oct 19 16:16 multi_led_intensity +-r--r--r-- 1 root root 4096 Oct 19 16:16 num_multi_leds + +Multicolor Class Brightness Control +=================================== +The multicolor class framework will calculate each monochrome LEDs intensity. + +The brightness level for each LED is calculated based on the color LED +intensity setting divided by the parent max_brightness setting multiplied by +the requested brightness. + +led_brightness = brightness * multi_led_intensity/max_brightness + +Example: +A user first writes the multi_led_intensity file with the brightness levels +for each LED that are necessary to achieve a blueish violet output from a +multicolor LED group. + +cat /sys/class/leds/multicolor:status/multi_led_index +green blue red + +echo 43 226 138 > /sys/class/leds/multicolor:status/multi_led_intensity + +red - + intensity = 138 + max_brightness = 255 +green - + intensity = 43 + max_brightness = 255 +blue - + intensity = 226 + max_brightness = 255 + +The user can control the brightness of that multicolor LED group by writing the +parent 'brightness' control. Assuming a parent max_brightness of 255 the user +may want to dim the LED color group to half. The user would write a value of +128 to the parent brightness file then the values written to each LED will be +adjusted base on this value. + +cat /sys/class/leds/multicolor:status/max_brightness +255 +echo 128 > /sys/class/leds/multicolor:status/brightness + +adjusted_red_value = 128 * 138/255 = 69 +adjusted_green_value = 128 * 43/255 = 21 +adjusted_blue_value = 128 * 226/255 = 113 + +Reading the parent brightness file will return the current brightness value of +the color LED group. + +cat /sys/class/leds/multicolor:status/brightness +128 diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index c664d84e1667..dd2f64be493c 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -30,6 +30,16 @@ config LEDS_CLASS_FLASH for the flash related features of a LED device. It can be built as a module. +config LEDS_CLASS_MULTI_COLOR + tristate "LED MultiColor LED Class Support" + depends on LEDS_CLASS + help + This option enables the multicolor LED sysfs class in /sys/class/leds. + It wraps LED class and adds multicolor LED specific sysfs attributes + and kernel internal API to it. You'll need this to provide support + for multicolor LEDs that are grouped together. This class is not + intended for single color LEDs. It can be built as a module. + config LEDS_BRIGHTNESS_HW_CHANGED bool "LED Class brightness_hw_changed attribute support" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 45235d5fb218..6cbaa3f232ac 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_NEW_LEDS) += led-core.o obj-$(CONFIG_LEDS_CLASS) += led-class.o obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o +obj-$(CONFIG_LEDS_CLASS_MULTI_COLOR) += led-class-multicolor.o obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o # LED Platform Drivers (keep this sorted, M-| sort) diff --git a/drivers/leds/led-class-multicolor.c b/drivers/leds/led-class-multicolor.c new file mode 100644 index 000000000000..fb49b517b0ce --- /dev/null +++ b/drivers/leds/led-class-multicolor.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0 +// LED Multi Color class interface +// Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/ +// Author: Dan Murphy + +#include +#include +#include +#include +#include +#include + +#include "leds.h" + +int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness) +{ + struct led_classdev *led_cdev = &mcled_cdev->led_cdev; + int i; + + for (i = 0; i < mcled_cdev->num_colors; i++) + mcled_cdev->multicolor_info[i].color_brightness = brightness * + mcled_cdev->multicolor_info[i].color_led_intensity / + led_cdev->max_brightness; + + return 0; +} +EXPORT_SYMBOL_GPL(led_mc_calc_color_components); + +static ssize_t multi_led_intensity_store(struct device *dev, + struct device_attribute *intensity_attr, + const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev); + int nrchars, offset = 0; + int intensity_value[LED_COLOR_ID_MAX]; + int i; + ssize_t ret; + + mutex_lock(&led_cdev->led_access); + + for (i = 0; i < mcled_cdev->num_colors; i++) { + ret = sscanf(buf + offset, "%i%n", + &intensity_value[i], &nrchars); + if (ret != 1) { + dev_err(led_cdev->dev, + "Incorrect number of LEDs expected %i values intensity was not applied\n", + mcled_cdev->num_colors); + goto err_out; + } + offset += nrchars; + } + + for (i = 0; i < mcled_cdev->num_colors; i++) + mcled_cdev->multicolor_info[i].color_led_intensity = + intensity_value[i]; + + led_set_brightness(led_cdev, led_cdev->brightness); +err_out: + ret = size; + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static ssize_t multi_led_intensity_show(struct device *dev, + struct device_attribute *intensity_attr, + char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev); + int len = 0; + int i; + + for (i = 0; i < mcled_cdev->num_colors; i++) + len += sprintf(buf + len, "%d ", + mcled_cdev->multicolor_info[i].color_led_intensity); + + len += sprintf(buf + len, "%s", "\n"); + + return len; +} +static DEVICE_ATTR_RW(multi_led_intensity); + +static ssize_t multi_led_index_show(struct device *dev, + struct device_attribute *multi_led_index_attr, + char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev); + int len = 0; + int index; + int i; + + for (i = 0; i < mcled_cdev->num_colors; i++) { + index = mcled_cdev->multicolor_info[i].color_index; + len += sprintf(buf + len, "%s ", led_colors[index]); + } + + len += sprintf(buf + len, "%s", "\n"); + + return len; +} +static DEVICE_ATTR_RO(multi_led_index); + +static ssize_t num_multi_leds_show(struct device *dev, + struct device_attribute *max_intensity_attr, + char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev); + + return sprintf(buf, "%d\n", mcled_cdev->num_colors); +} +static DEVICE_ATTR_RO(num_multi_leds); + +static struct attribute *led_multicolor_attrs[] = { + &dev_attr_multi_led_intensity.attr, + &dev_attr_multi_led_index.attr, + &dev_attr_num_multi_leds.attr, + NULL, +}; +ATTRIBUTE_GROUPS(led_multicolor); + +int led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data) +{ + struct led_classdev *led_cdev; + + if (!mcled_cdev) + return -EINVAL; + + if (!mcled_cdev->num_colors) + return -EINVAL; + + led_cdev = &mcled_cdev->led_cdev; + mcled_cdev->led_cdev.groups = led_multicolor_groups; + + return led_classdev_register_ext(parent, led_cdev, init_data); +} +EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext); + +void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev) +{ + if (!mcled_cdev) + return; + + led_classdev_unregister(&mcled_cdev->led_cdev); +} +EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister); + +static void devm_led_classdev_multicolor_release(struct device *dev, void *res) +{ + led_classdev_multicolor_unregister(*(struct led_classdev_mc **)res); +} + +int devm_led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data) +{ + struct led_classdev_mc **dr; + int ret; + + dr = devres_alloc(devm_led_classdev_multicolor_release, + sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + ret = led_classdev_multicolor_register_ext(parent, mcled_cdev, + init_data); + if (ret) { + devres_free(dr); + return ret; + } + + *dr = mcled_cdev; + devres_add(parent, dr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register_ext); + +static int devm_led_classdev_multicolor_match(struct device *dev, + void *res, void *data) +{ + struct led_classdev_mc **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +void devm_led_classdev_multicolor_unregister(struct device *dev, + struct led_classdev_mc *mcled_cdev) +{ + WARN_ON(devres_release(dev, + devm_led_classdev_multicolor_release, + devm_led_classdev_multicolor_match, mcled_cdev)); +} +EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_unregister); + +MODULE_AUTHOR("Dan Murphy "); +MODULE_DESCRIPTION("Multi Color LED class interface"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/led-class-multicolor.h b/include/linux/led-class-multicolor.h new file mode 100644 index 000000000000..7c5befb270f8 --- /dev/null +++ b/include/linux/led-class-multicolor.h @@ -0,0 +1,121 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* LED Multicolor class interface + * Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/ + */ + +#ifndef __LINUX_MULTICOLOR_LEDS_H_INCLUDED +#define __LINUX_MULTICOLOR_LEDS_H_INCLUDED + +#include +#include + +struct led_mc_subled { + int color_index; + int color_brightness; + int color_led_intensity; + int color_channel; +}; + +struct led_classdev_mc { + /* led class device */ + struct led_classdev led_cdev; + int num_colors; + + struct led_mc_subled *multicolor_info; +}; + +static inline struct led_classdev_mc *lcdev_to_mccdev( + struct led_classdev *led_cdev) +{ + return container_of(led_cdev, struct led_classdev_mc, led_cdev); +} + +#if IS_ENABLED(CONFIG_LEDS_CLASS_MULTI_COLOR) +/** + * led_classdev_multicolor_register_ext - register a new object of led_classdev + * class with support for multicolor LEDs + * @parent: the multicolor LED to register + * @mcled_cdev: the led_classdev_mc structure for this device + * @init_data: the LED class Multi color device initialization data + * + * Returns: 0 on success or negative error value on failure + */ +int led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data); + +static inline int led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{ + return led_classdev_multicolor_register_ext(parent, mcled_cdev, NULL); +} + +/** + * led_classdev_multicolor_unregister - unregisters an object of led_classdev + * class with support for multicolor LEDs + * @mcled_cdev: the multicolor LED to unregister + * + * Unregister a previously registered via led_classdev_multicolor_register + * object + */ +void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev); + +/* Calculate brightness for the monochrome LED cluster */ +int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness); + +int devm_led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data); + +static inline int devm_led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{ + return devm_led_classdev_multicolor_register_ext(parent, mcled_cdev, + NULL); +} + +void devm_led_classdev_multicolor_unregister(struct device *parent, + struct led_classdev_mc *mcled_cdev); +#else + +static inline int led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data) +{ + return -EINVAL; +} + +static inline int led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{ + return led_classdev_multicolor_register_ext(parent, mcled_cdev, NULL); +} + +static inline void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev) {}; +static inline int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness) +{ + return -EINVAL; +} + +static inline int devm_led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data) +{ + return -EINVAL; +} + +static inline int devm_led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{ + return devm_led_classdev_multicolor_register_ext(parent, mcled_cdev, + NULL); +} + +static inline void devm_led_classdev_multicolor_unregister(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{}; + +#endif /* IS_ENABLED(CONFIG_LEDS_CLASS_MULTI_COLOR) */ +#endif /* __LINUX_MULTICOLOR_LEDS_H_INCLUDED */