From patchwork Fri May 31 16:33:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= X-Patchwork-Id: 800749 Received: from todd.t-8ch.de (todd.t-8ch.de [159.69.126.157]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 827C317D890; Fri, 31 May 2024 16:33:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.69.126.157 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717173225; cv=none; b=uxsykYe+Ak4I4PfyrhlDfrG0oGqU78nY4N3cIkUcw6asXuGh9xOBRSfiRMwaOaz1/6eN5jRd5aW5CAj9e3t7O0hOtwMt3jtD255Q+VI/99mJRL5rNKq1cEHdO1Sb76xv3v23+Ss8jsq0YagiIJhU8pra7N3gilhkdFt+f0zEbGo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717173225; c=relaxed/simple; bh=HufEwWkbpTxiiXisn3yy7UxETsQlWGuLUyx1Km4hSeE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=cxxW44JTFZaqELq7Xg/ZuvN0ysVWgoNox61or7pq+CZF2z4mEv8NLMTT3xzAg0pUSS1tCLWfoyrFmDi9kuX8B8WiIA29A3EAQqRO4VRr+LwRJ+0OWfrXlaGxMTUfe2kOmHaakCqkarlqfdCSKXahB5bq5KuZYAZd5T8CnSNSnN8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net; spf=pass smtp.mailfrom=weissschuh.net; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b=MzeN/PzW; arc=none smtp.client-ip=159.69.126.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b="MzeN/PzW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=weissschuh.net; s=mail; t=1717173219; bh=HufEwWkbpTxiiXisn3yy7UxETsQlWGuLUyx1Km4hSeE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=MzeN/PzWqHzcqp6svbZnkDt9BLPM66TExUYl88xQXZm6LfZ1mtKOFbpw/kG17p3rK VJQgweGUCd0KGJrvLrDJGOiwlk1r4OXJ2RjbsLjzhb1iCuLBIWZnTbqJC+3lFETaTS wOUQmCBn88GN5wx1xWYBf8wj05LfNK+CRAnqOTKc= From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= Date: Fri, 31 May 2024 18:33:34 +0200 Subject: [PATCH v2 4/5] leds: Add ChromeOS EC driver Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240531-cros_ec-led-v2-4-6cc34408b40d@weissschuh.net> References: <20240531-cros_ec-led-v2-0-6cc34408b40d@weissschuh.net> In-Reply-To: <20240531-cros_ec-led-v2-0-6cc34408b40d@weissschuh.net> To: Pavel Machek , Lee Jones , =?utf-8?q?Thoma?= =?utf-8?q?s_Wei=C3=9Fschuh?= , Benson Leung , Guenter Roeck , Tzung-Bi Shih Cc: linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org, chrome-platform@lists.linux.dev, Dustin Howett , Mario Limonciello , =?utf-8?q?Thomas_Wei=C3=9Fs?= =?utf-8?q?chuh?= X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1717173219; l=11102; i=linux@weissschuh.net; s=20221212; h=from:subject:message-id; bh=HufEwWkbpTxiiXisn3yy7UxETsQlWGuLUyx1Km4hSeE=; b=7/Wq4ptLpJtLBlXAG2nbtG9IwS2WLo2umkLCme2rlW+68pWV5VhiYFiKVJ3uol4ju+OyTKxHT atPl5ya69IvBFILS/FxNhhMZ/g1FbEvC5TAtjyU72CdZLAin++2wR+v X-Developer-Key: i=linux@weissschuh.net; a=ed25519; pk=KcycQgFPX2wGR5azS7RhpBqedglOZVgRPfdFSPB1LNw= The ChromeOS Embedded Controller exposes an LED control command. Expose its functionality through the leds subsystem. The LEDs are exposed as multicolor devices. A hardware trigger, which is active by default, is provided to let the EC itself take over control over the LED. The driver is designed to be probed via the cros_ec mfd device. Signed-off-by: Thomas Weißschuh --- MAINTAINERS | 5 + drivers/leds/Kconfig | 15 +++ drivers/leds/Makefile | 1 + drivers/leds/leds-cros_ec.c | 297 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 318 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index d6c90161c7bf..003118d088f0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5135,6 +5135,11 @@ S: Maintained F: Documentation/devicetree/bindings/sound/google,cros-ec-codec.yaml F: sound/soc/codecs/cros_ec_codec.* +CHROMEOS EC LED DRIVER +M: Thomas Weißschuh +S: Maintained +F: drivers/leds/leds-cros_ec.c + CHROMEOS EC SUBDRIVERS M: Benson Leung R: Guenter Roeck diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 05e6af88b88c..aa2fec9a34ed 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -179,6 +179,21 @@ config LEDS_CR0014114 To compile this driver as a module, choose M here: the module will be called leds-cr0014114. +config LEDS_CROS_EC + tristate "LED Support for ChromeOS EC" + depends on MFD_CROS_EC_DEV + depends on LEDS_CLASS_MULTICOLOR + select LEDS_TRIGGERS + default MFD_CROS_EC_DEV + help + This option enables support for LEDs managed by ChromeOS ECs. + All LEDs exposed by the EC are supported in multicolor mode. + A hardware trigger to switch back to the automatic behaviour is + provided. + + To compile this driver as a module, choose M here: the module + will be called leds-cros_ec. + config LEDS_EL15203000 tristate "LED Support for Crane EL15203000" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index effdfc6f1e95..3491904e13f7 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_LEDS_CLEVO_MAIL) += leds-clevo-mail.o obj-$(CONFIG_LEDS_COBALT_QUBE) += leds-cobalt-qube.o obj-$(CONFIG_LEDS_COBALT_RAQ) += leds-cobalt-raq.o obj-$(CONFIG_LEDS_CPCAP) += leds-cpcap.o +obj-$(CONFIG_LEDS_CROS_EC) += leds-cros_ec.o obj-$(CONFIG_LEDS_DA903X) += leds-da903x.o obj-$(CONFIG_LEDS_DA9052) += leds-da9052.o obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o diff --git a/drivers/leds/leds-cros_ec.c b/drivers/leds/leds-cros_ec.c new file mode 100644 index 000000000000..193a09a9e78a --- /dev/null +++ b/drivers/leds/leds-cros_ec.c @@ -0,0 +1,297 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * ChromeOS EC LED Driver + * + * Copyright (C) 2024 Thomas Weißschuh + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRV_NAME "cros-ec-led" + +static const char * const cros_ec_led_functions[] = { + [EC_LED_ID_BATTERY_LED] = LED_FUNCTION_CHARGING, + [EC_LED_ID_POWER_LED] = LED_FUNCTION_POWER, + [EC_LED_ID_ADAPTER_LED] = "adapter", + [EC_LED_ID_LEFT_LED] = "left", + [EC_LED_ID_RIGHT_LED] = "right", + [EC_LED_ID_RECOVERY_HW_REINIT_LED] = "recovery-hw-reinit", + [EC_LED_ID_SYSRQ_DEBUG_LED] = "sysrq-debug", +}; + +static_assert(ARRAY_SIZE(cros_ec_led_functions) == EC_LED_ID_COUNT); + +static const int cros_ec_led_to_linux_id[] = { + [EC_LED_COLOR_RED] = LED_COLOR_ID_RED, + [EC_LED_COLOR_GREEN] = LED_COLOR_ID_GREEN, + [EC_LED_COLOR_BLUE] = LED_COLOR_ID_BLUE, + [EC_LED_COLOR_YELLOW] = LED_COLOR_ID_YELLOW, + [EC_LED_COLOR_WHITE] = LED_COLOR_ID_WHITE, + [EC_LED_COLOR_AMBER] = LED_COLOR_ID_AMBER, +}; + +static_assert(ARRAY_SIZE(cros_ec_led_to_linux_id) == EC_LED_COLOR_COUNT); + +static const int cros_ec_linux_to_ec_id[] = { + [LED_COLOR_ID_RED] = EC_LED_COLOR_RED, + [LED_COLOR_ID_GREEN] = EC_LED_COLOR_GREEN, + [LED_COLOR_ID_BLUE] = EC_LED_COLOR_BLUE, + [LED_COLOR_ID_YELLOW] = EC_LED_COLOR_YELLOW, + [LED_COLOR_ID_WHITE] = EC_LED_COLOR_WHITE, + [LED_COLOR_ID_AMBER] = EC_LED_COLOR_AMBER, +}; + +struct cros_ec_led_priv { + struct led_classdev_mc led_mc_cdev; + struct cros_ec_device *cros_ec; + enum ec_led_id led_id; +}; + +static inline struct cros_ec_led_priv *cros_ec_led_cdev_to_priv(struct led_classdev *led_cdev) +{ + return container_of(lcdev_to_mccdev(led_cdev), struct cros_ec_led_priv, led_mc_cdev); +} + +union cros_ec_led_cmd_data { + struct ec_params_led_control req; + struct ec_response_led_control resp; +} __packed; + +static int cros_ec_led_send_cmd(struct cros_ec_device *cros_ec, + union cros_ec_led_cmd_data *arg) +{ + int ret; + struct { + struct cros_ec_command msg; + union cros_ec_led_cmd_data data; + } __packed buf = { + .msg = { + .version = 1, + .command = EC_CMD_LED_CONTROL, + .insize = sizeof(arg->resp), + .outsize = sizeof(arg->req), + }, + .data.req = arg->req + }; + + ret = cros_ec_cmd_xfer_status(cros_ec, &buf.msg); + if (ret < 0) + return ret; + + arg->resp = buf.data.resp; + + return 0; +} + +static int cros_ec_led_trigger_activate(struct led_classdev *led_cdev) +{ + struct cros_ec_led_priv *priv = cros_ec_led_cdev_to_priv(led_cdev); + union cros_ec_led_cmd_data arg = {}; + + arg.req.led_id = priv->led_id; + arg.req.flags = EC_LED_FLAGS_AUTO; + + return cros_ec_led_send_cmd(priv->cros_ec, &arg); +} + +static struct led_hw_trigger_type cros_ec_led_trigger_type; + +static struct led_trigger cros_ec_led_trigger = { + .name = "chromeos-auto", + .trigger_type = &cros_ec_led_trigger_type, + .activate = cros_ec_led_trigger_activate, +}; + +static int cros_ec_led_brightness_set_blocking(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct cros_ec_led_priv *priv = cros_ec_led_cdev_to_priv(led_cdev); + union cros_ec_led_cmd_data arg = {}; + enum ec_led_colors led_color; + struct mc_subled *subled; + size_t i; + + led_mc_calc_color_components(&priv->led_mc_cdev, brightness); + + arg.req.led_id = priv->led_id; + + for (i = 0; i < priv->led_mc_cdev.num_colors; i++) { + subled = &priv->led_mc_cdev.subled_info[i]; + led_color = cros_ec_linux_to_ec_id[subled->color_index]; + arg.req.brightness[led_color] = subled->brightness; + } + + return cros_ec_led_send_cmd(priv->cros_ec, &arg); +} + +static int cros_ec_led_count_subleds(struct device *dev, + struct ec_response_led_control *resp, + unsigned int *max_brightness) +{ + unsigned int range, common_range = 0; + int num_subleds = 0; + size_t i; + + for (i = 0; i < EC_LED_COLOR_COUNT; i++) { + range = resp->brightness_range[i]; + + if (!range) + continue; + + num_subleds++; + + if (!common_range) + common_range = range; + + if (common_range != range) { + /* The multicolor LED API expects a uniform max_brightness */ + dev_warn(dev, "Inconsistent LED brightness values\n"); + return -EINVAL; + } + } + + if (!num_subleds) + return -EINVAL; + + *max_brightness = common_range; + return num_subleds; +} + +static const char *cros_ec_led_get_color_name(struct led_classdev_mc *led_mc_cdev) +{ + int color; + + if (led_mc_cdev->num_colors == 1) + color = led_mc_cdev->subled_info[0].color_index; + else + color = LED_COLOR_ID_MULTI; + + return led_get_color_name(color); +} + +static int cros_ec_led_probe_led(struct device *dev, struct cros_ec_device *cros_ec, + enum ec_led_id id) +{ + union cros_ec_led_cmd_data arg = {}; + struct cros_ec_led_priv *priv; + struct led_classdev *led_cdev; + struct mc_subled *subleds; + int ret, num_subleds; + size_t i, subled; + + arg.req.led_id = id; + arg.req.flags = EC_LED_FLAGS_QUERY; + ret = cros_ec_led_send_cmd(cros_ec, &arg); + /* Unknown LED, skip */ + if (ret == -EINVAL) + return 0; + if (ret == -EOPNOTSUPP) + return -ENODEV; + if (ret < 0) + return ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + num_subleds = cros_ec_led_count_subleds(dev, &arg.resp, + &priv->led_mc_cdev.led_cdev.max_brightness); + if (num_subleds < 0) + return num_subleds; + + priv->cros_ec = cros_ec; + priv->led_id = id; + + subleds = devm_kcalloc(dev, num_subleds, sizeof(*subleds), GFP_KERNEL); + if (!subleds) + return -ENOMEM; + + subled = 0; + for (i = 0; i < EC_LED_COLOR_COUNT; i++) { + if (!arg.resp.brightness_range[i]) + continue; + + subleds[subled].color_index = cros_ec_led_to_linux_id[i]; + subleds[subled].intensity = 100; + subled++; + } + + priv->led_mc_cdev.subled_info = subleds; + priv->led_mc_cdev.num_colors = num_subleds; + + led_cdev = &priv->led_mc_cdev.led_cdev; + led_cdev->brightness_set_blocking = cros_ec_led_brightness_set_blocking; + led_cdev->trigger_type = &cros_ec_led_trigger_type; + led_cdev->hw_control_trigger = cros_ec_led_trigger.name; + + led_cdev->name = devm_kasprintf(dev, GFP_KERNEL, "chromeos:%s:%s", + cros_ec_led_get_color_name(&priv->led_mc_cdev), + cros_ec_led_functions[id]); + if (!led_cdev->name) + return -ENOMEM; + + return devm_led_classdev_multicolor_register(dev, &priv->led_mc_cdev); +} + +static int cros_ec_led_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent); + struct cros_ec_device *cros_ec = ec_dev->ec_dev; + int ret = 0; + size_t i; + + for (i = 0; i < EC_LED_ID_COUNT; i++) { + ret = cros_ec_led_probe_led(dev, cros_ec, i); + if (ret) + break; + } + + return ret; +} + +static const struct platform_device_id cros_ec_led_id[] = { + { DRV_NAME, 0 }, + {} +}; + +static struct platform_driver cros_ec_led_driver = { + .driver.name = DRV_NAME, + .probe = cros_ec_led_probe, + .id_table = cros_ec_led_id, +}; + +static int __init cros_ec_led_init(void) +{ + int ret; + + ret = led_trigger_register(&cros_ec_led_trigger); + if (ret) + return ret; + + ret = platform_driver_register(&cros_ec_led_driver); + if (ret) + led_trigger_unregister(&cros_ec_led_trigger); + + return ret; +}; +module_init(cros_ec_led_init); + +static void __exit cros_ec_led_exit(void) +{ + platform_driver_unregister(&cros_ec_led_driver); + led_trigger_unregister(&cros_ec_led_trigger); +}; +module_exit(cros_ec_led_exit); + +MODULE_DEVICE_TABLE(platform, cros_ec_led_id); +MODULE_DESCRIPTION("ChromeOS EC LED Driver"); +MODULE_AUTHOR("Thomas Weißschuh