Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760309AbcCDVXD (ORCPT ); Fri, 4 Mar 2016 16:23:03 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:35353 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759649AbcCDVXA (ORCPT ); Fri, 4 Mar 2016 16:23:00 -0500 From: Heiner Kallweit Subject: [PATCH v7 1/5] leds: core: add generic support for RGB LED's To: Jacek Anaszewski Cc: linux-leds@vger.kernel.org, Benjamin Tissoires , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Message-ID: <56D9F973.8090207@gmail.com> Date: Fri, 4 Mar 2016 22:09:07 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10152 Lines: 304 Add generic support for RGB LED's. Basic idea is to use enum led_brightness also for the hue and saturation color components.This allows to implement the color extension w/o changes to struct led_classdev. Select LEDS_RGB to enable building drivers using the RGB extension. Flag LED_SET_HUE_SAT allows to specify that hue / saturation should be overridden even if the provided values are zero. Some examples for writing values to /sys/class/leds//brightness: (now also hex notation can be used) 255 -> set full brightness and keep existing color if set 0 -> switch LED off but keep existing color so that it can be restored if the LED is switched on again later 0x1000000 -> switch LED off and set also hue and saturation to 0 0x00ffff -> set full brightness, full saturation and set hue to 0 (red) Signed-off-by: Heiner Kallweit --- v2: - move extension-specific code into a separate source file and introduce config symbol LEDS_HSV for it - create separate patch for the extension to sysfs - use variable name led_cdev as in the rest if the core - rename to_hsv to led_validate_brightness - rename LED_BRIGHTNESS_SET_COLOR to LED_SET_HSV - introduce helper is_off for checking whether V part of a HSV value is zero v3: - change Kconfig to use depend instead of select, add help message, and change config symbol to LEDS_COLOR - change LED core object file name in Makefile - rename flag LED_SET_HSV to LED_SET_COLOR - rename is_off to led_is_off - rename led_validate-brightness to led_confine_brightness - rename variable in led_confine_brightness - add dummy enum led_brightness value to enforce 32bit enum - rename led-hsv-core.c to led-color-core.c - move check of provided brightness value to led_confine_brightness v4: - change config symbol name to LEDS_RGB - change name of new file to led-rgb-core.c - factor out part of led_confine_brightness - change led_is_off to __is_set_brightness - in led_set_software_blink pass led_cdev->max_brightness instead of LED_FULL - rename LED_SET_COLOR to LED_SET_HUE_SAT v5: - change "RGB Color LED" to "RGB LED" in Kconfig - move definition of LED_HUE_SAT_MASK to drivers/leds/leds.h - rename LED_DEV_CAP_HSV to LED_DEV_CAP_RGB v6: - no change v7: - removed "Color" from RGB Color LED in commit message and title - don't include linux/kernel.h in led-rgb-core.c - keep definition of LED_DEV_CAP_[] flags together --- drivers/leds/Kconfig | 11 +++++++++++ drivers/leds/Makefile | 4 +++- drivers/leds/led-class.c | 2 +- drivers/leds/led-core.c | 16 +++++++++------- drivers/leds/led-rgb-core.c | 39 +++++++++++++++++++++++++++++++++++++++ drivers/leds/leds.h | 18 ++++++++++++++++++ include/linux/leds.h | 11 ++++++++++- 7 files changed, 91 insertions(+), 10 deletions(-) create mode 100644 drivers/leds/led-rgb-core.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 7f940c2..5b1c852 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -13,6 +13,13 @@ menuconfig NEW_LEDS if NEW_LEDS +config LEDS_RGB + bool "RGB LED Support" + help + This option enables support for RGB Color LED devices. + Sysfs attribute brightness is interpreted as a HSV color value. + For details see Documentation/leds/leds-class.txt. + config LEDS_CLASS tristate "LED Class Support" help @@ -29,6 +36,10 @@ config LEDS_CLASS_FLASH for the flash related features of a LED device. It can be built as a module. +if LEDS_RGB +comment "RGB LED drivers" +endif # LEDS_RGB + comment "LED drivers" config LEDS_88PM860X diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index e9d5309..cc3676f 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -1,6 +1,8 @@ # LED Core -obj-$(CONFIG_NEW_LEDS) += led-core.o +obj-$(CONFIG_NEW_LEDS) += led-core-objs.o +led-core-objs-y := led-core.o +led-core-objs-$(CONFIG_LEDS_RGB) += led-rgb-core.o obj-$(CONFIG_LEDS_CLASS) += led-class.o obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index aa84e5b..007a5b3 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -53,7 +53,7 @@ static ssize_t brightness_store(struct device *dev, if (ret) goto unlock; - if (state == LED_OFF) + if (!__is_brightness_set(state)) led_trigger_remove(led_cdev); led_set_brightness(led_cdev, state); diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c index 3495d5d..e75b0c8 100644 --- a/drivers/leds/led-core.c +++ b/drivers/leds/led-core.c @@ -62,7 +62,7 @@ static void led_timer_function(unsigned long data) } brightness = led_get_brightness(led_cdev); - if (!brightness) { + if (!__is_brightness_set(brightness)) { /* Time to switch the LED on. */ brightness = led_cdev->blink_brightness; delay = led_cdev->blink_delay_on; @@ -133,8 +133,9 @@ static void led_set_software_blink(struct led_classdev *led_cdev, if (current_brightness) led_cdev->blink_brightness = current_brightness; if (!led_cdev->blink_brightness) - led_cdev->blink_brightness = led_cdev->max_brightness; - + led_cdev->blink_brightness = + led_confine_brightness(led_cdev, + led_cdev->max_brightness); led_cdev->blink_delay_on = delay_on; led_cdev->blink_delay_off = delay_off; @@ -235,12 +236,13 @@ void led_set_brightness(struct led_classdev *led_cdev, * work queue task to avoid problems in case we are called * from hard irq context. */ - if (brightness == LED_OFF) { + if (!__is_brightness_set(brightness)) { led_cdev->flags |= LED_BLINK_DISABLE; schedule_work(&led_cdev->set_brightness_work); } else { led_cdev->flags |= LED_BLINK_BRIGHTNESS_CHANGE; - led_cdev->blink_brightness = brightness; + led_cdev->blink_brightness = + led_confine_brightness(led_cdev, brightness); } return; } @@ -265,7 +267,7 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nopm); void led_set_brightness_nosleep(struct led_classdev *led_cdev, enum led_brightness value) { - led_cdev->brightness = min(value, led_cdev->max_brightness); + led_cdev->brightness = led_confine_brightness(led_cdev, value); if (led_cdev->flags & LED_SUSPENDED) return; @@ -280,7 +282,7 @@ int led_set_brightness_sync(struct led_classdev *led_cdev, if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) return -EBUSY; - led_cdev->brightness = min(value, led_cdev->max_brightness); + led_cdev->brightness = led_confine_brightness(led_cdev, value); if (led_cdev->flags & LED_SUSPENDED) return 0; diff --git a/drivers/leds/led-rgb-core.c b/drivers/leds/led-rgb-core.c new file mode 100644 index 0000000..cbd8b35 --- /dev/null +++ b/drivers/leds/led-rgb-core.c @@ -0,0 +1,39 @@ +/* + * LED Class Color Support + * + * Author: Heiner Kallweit + * + * 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 "leds.h" + +/* + * The color extension handles RGB LEDs but uses a HSV color model internally. + * led_rgb_adjust_hue_sat sets hue and saturation part of the HSV color value. + */ +static enum led_brightness led_rgb_adjust_hue_sat(struct led_classdev *led_cdev, + enum led_brightness value) +{ + /* LED_SET_HUE_SAT sets hue and saturation even if both are zero */ + if (value & LED_SET_HUE_SAT || value > LED_FULL) + return value & LED_HUE_SAT_MASK; + else + return led_cdev->brightness & ~LED_BRIGHTNESS_MASK; +} + +enum led_brightness led_confine_brightness(struct led_classdev *led_cdev, + enum led_brightness value) +{ + enum led_brightness brightness = 0; + + if (led_cdev->flags & LED_DEV_CAP_RGB) + brightness = led_rgb_adjust_hue_sat(led_cdev, value); + + return brightness | + min(value & LED_BRIGHTNESS_MASK, led_cdev->max_brightness); +} diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h index db3f20d..b853f54 100644 --- a/drivers/leds/leds.h +++ b/drivers/leds/leds.h @@ -16,17 +16,35 @@ #include #include +#define LED_BRIGHTNESS_MASK 0x000000ff +#define LED_HUE_SAT_MASK 0x00ffff00 + static inline int led_get_brightness(struct led_classdev *led_cdev) { return led_cdev->brightness; } +static inline bool __is_brightness_set(enum led_brightness brightness) +{ + return (brightness & LED_BRIGHTNESS_MASK) != LED_OFF; +} + void led_init_core(struct led_classdev *led_cdev); void led_stop_software_blink(struct led_classdev *led_cdev); void led_set_brightness_nopm(struct led_classdev *led_cdev, enum led_brightness value); void led_set_brightness_nosleep(struct led_classdev *led_cdev, enum led_brightness value); +#if IS_ENABLED(CONFIG_LEDS_RGB) +enum led_brightness led_confine_brightness(struct led_classdev *led_cdev, + enum led_brightness value); +#else +static inline enum led_brightness led_confine_brightness( + struct led_classdev *led_cdev, enum led_brightness value) +{ + return min(value, led_cdev->max_brightness); +} +#endif extern struct rw_semaphore leds_list_lock; extern struct list_head leds_list; diff --git a/include/linux/leds.h b/include/linux/leds.h index f203a8f..58e8299 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -29,8 +29,16 @@ enum led_brightness { LED_OFF = 0, LED_HALF = 127, LED_FULL = 255, + /* + * dummy enum value to make gcc use a 32 bit type for the enum + * even if compiled with -fshort-enums. This is needed for + * the enum to store hsv values. + */ + LED_LEVEL_DUMMY = 0xffffffff, }; +#define LED_SET_HUE_SAT BIT(24) + struct led_classdev { const char *name; enum led_brightness brightness; @@ -49,7 +57,8 @@ struct led_classdev { #define LED_BLINK_DISABLE (1 << 21) #define LED_SYSFS_DISABLE (1 << 22) #define LED_DEV_CAP_FLASH (1 << 23) -#define LED_HW_PLUGGABLE (1 << 24) +#define LED_DEV_CAP_RGB (1 << 24) +#define LED_HW_PLUGGABLE (1 << 25) /* Set LED brightness level * Must not sleep. Use brightness_set_blocking for drivers -- 2.7.1