From nobody Sat Feb 7 14:39:32 2026 Received: from mout-p-202.mailbox.org (mout-p-202.mailbox.org [80.241.56.172]) (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 6788F17A2F0; Sun, 18 Jan 2026 16:50:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768755046; cv=none; b=dTgConoRZpkYhgWEMae89IJfv0c7eooSYITERPt2t1SRLKEI/YUiEtCp+mypEa3Q1mrXNTgDHnO7JrQPP/DjANVFpqMOHkWHIgaNLCmxwW/3jLzAyUl9Hlods9T5R2r4xNmWwWBwQ4vKYcVIBI6uPw4Kn+BH4Mx5MEoZLGnYuPA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768755046; c=relaxed/simple; bh=PXskonqszq9ZCvvJ/HU7aqSGh/SWRcCqKx5uPz5G6Wc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gkaqpC36x3RK56XWlZijmdz4Iljx8g/iK5UIkg7xyviGhHYt4PHY4zSPezC7IYyVk9SvZ5ltrJqe0M8b3sNzOaJ4VSSjiltZObDavzEoOAVh0UJwVHv0n+FEbnfJJAKqk/3T8xOKAMXxAcCAA5HM+fT2GJFXm9DxIxr2JHo/Wco= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=timmermann.space; spf=pass smtp.mailfrom=timmermann.space; arc=none smtp.client-ip=80.241.56.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=timmermann.space Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=timmermann.space Received: from smtp202.mailbox.org (smtp202.mailbox.org [10.196.197.202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-202.mailbox.org (Postfix) with ESMTPS id 4dvKN04KQmz9tnG; Sun, 18 Jan 2026 17:50:40 +0100 (CET) From: Lukas Timmermann To: lee@kernel.org, pavel@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux@timmermann.space, Krzysztof Kozlowski Subject: [PATCH v14 1/2] dt-bindings: leds: Add new as3668 support Date: Sun, 18 Jan 2026 17:50:09 +0100 Message-ID: <20260118165010.902086-2-linux@timmermann.space> In-Reply-To: <20260118165010.902086-1-linux@timmermann.space> References: <20260118165010.902086-1-linux@timmermann.space> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The bindings are incomplete, as the GPIO/Audio Input pin is still undocumented. The hardware used for testing this patch series does not allow modification, so the mentioned pin has been omitted. Signed-off-by: Lukas Timmermann Reviewed-by: Krzysztof Kozlowski --- .../devicetree/bindings/leds/ams,as3668.yaml | 74 +++++++++++++++++++ MAINTAINERS | 6 ++ 2 files changed, 80 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/ams,as3668.yaml diff --git a/Documentation/devicetree/bindings/leds/ams,as3668.yaml b/Docum= entation/devicetree/bindings/leds/ams,as3668.yaml new file mode 100644 index 000000000000..d1d73782da55 --- /dev/null +++ b/Documentation/devicetree/bindings/leds/ams,as3668.yaml @@ -0,0 +1,74 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/ams,as3668.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Osram 4-channel i2c LED driver + +maintainers: + - Lukas Timmermann + +description: + This IC can drive up to four separate LEDs. + Having four channels suggests it could be used with a single RGBW LED. + +properties: + compatible: + const: ams,as3668 + + reg: + maxItems: 1 + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + +patternProperties: + "^led@[0-3]$": + type: object + $ref: common.yaml# + unevaluatedProperties: false + + properties: + reg: + maxItems: 1 + +required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + +additionalProperties: false + +examples: + - | + #include + + i2c { + #address-cells =3D <1>; + #size-cells =3D <0>; + + led-controller@42 { + compatible =3D "ams,as3668"; + reg =3D <0x42>; + #address-cells =3D <1>; + #size-cells =3D <0>; + + led@0 { + reg =3D <0x0>; + function =3D LED_FUNCTION_STATUS; + color =3D ; + }; + + led@1 { + reg =3D <0x1>; + function =3D LED_FUNCTION_STATUS; + color =3D ; + }; + }; + }; + diff --git a/MAINTAINERS b/MAINTAINERS index c59316109e3f..091206c54c63 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3506,6 +3506,12 @@ L: linux-leds@vger.kernel.org S: Maintained F: drivers/leds/flash/leds-as3645a.c =20 +AS3668 LED DRIVER +M: Lukas Timmermann +L: linux-leds@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/leds/ams,as3668.yaml + ASAHI KASEI AK7375 LENS VOICE COIL DRIVER M: Tianshu Qiu L: linux-media@vger.kernel.org --=20 2.52.0 From nobody Sat Feb 7 14:39:32 2026 Received: from mout-p-202.mailbox.org (mout-p-202.mailbox.org [80.241.56.172]) (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 8CD551A01C6; Sun, 18 Jan 2026 16:50:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768755047; cv=none; b=klA4ftuRSPZqQloRRoK+XRWD5zmCgkbFh/bcfF9LCbrlcQ41bv71rNa9TaAD5NQOEld19jWiH2k/GfVGH1jYkn6MfmuobD6EDtSkJLudTtEfxeb9SuSKazNPzyTouwZY2+89/ApG+e3fK7DwfPyc3cGz6W6gQOn3k7cM+VmB83s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768755047; c=relaxed/simple; bh=oS08Ctmgkf81BXUOk6PIyAqNgpwXX5Fmvq9G4A4f+Qc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VCfy/4cLtd5rkszPMFeKqU6noEHA7MaW8pqeVCXcrUlp07Hdg0qUW3X/UGsjhleJF6p5kGYOaaMLr72SeUaSZW2ck10kEPfPeZoYmyy+3WkpCsiU363fkBKrik1jsuc8fRW7RI4/2cZj86KinnQzxHmEMV3Rk14sOPrZ8tiN/sw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=timmermann.space; spf=pass smtp.mailfrom=timmermann.space; arc=none smtp.client-ip=80.241.56.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=timmermann.space Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=timmermann.space Received: from smtp202.mailbox.org (smtp202.mailbox.org [10.196.197.202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-202.mailbox.org (Postfix) with ESMTPS id 4dvKN22Wk3z9tnv; Sun, 18 Jan 2026 17:50:42 +0100 (CET) From: Lukas Timmermann To: lee@kernel.org, pavel@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux@timmermann.space Subject: [PATCH v14 2/2] leds: as3668: Driver for the ams Osram 4-channel i2c LED driver Date: Sun, 18 Jan 2026 17:50:10 +0100 Message-ID: <20260118165010.902086-3-linux@timmermann.space> In-Reply-To: <20260118165010.902086-1-linux@timmermann.space> References: <20260118165010.902086-1-linux@timmermann.space> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Since there were no existing drivers for the AS3668 or related devices, a new driver was introduced in a separate file. Similar devices were reviewed, but none shared enough characteristics to justify code reuse. As a result, this driver is written specifically for the AS3668. Signed-off-by: Lukas Timmermann --- MAINTAINERS | 1 + drivers/leds/Kconfig | 13 +++ drivers/leds/Makefile | 1 + drivers/leds/leds-as3668.c | 202 +++++++++++++++++++++++++++++++++++++ 4 files changed, 217 insertions(+) create mode 100644 drivers/leds/leds-as3668.c diff --git a/MAINTAINERS b/MAINTAINERS index 091206c54c63..945d78fef380 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3511,6 +3511,7 @@ M: Lukas Timmermann L: linux-leds@vger.kernel.org S: Maintained F: Documentation/devicetree/bindings/leds/ams,as3668.yaml +F: drivers/leds/leds-as3668.c =20 ASAHI KASEI AK7375 LENS VOICE COIL DRIVER M: Tianshu Qiu diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index a104cbb0a001..ec37d55ac14e 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -100,6 +100,19 @@ config LEDS_ARIEL =20 Say Y to if your machine is a Dell Wyse 3020 thin client. =20 +config LEDS_OSRAM_AMS_AS3668 + tristate "LED support for Osram AMS AS3668" + depends on LEDS_CLASS + depends on I2C + help + This option enables support for the Osram AMS AS3668 LED controller. + The AS3668 provides up to four LED channels and is controlled via + the I2C bus. This driver offers basic brightness control for each + channel, without support for blinking or other advanced features. + + To compile this driver as a module, choose M here: the module + will be called leds-as3668. + config LEDS_AW200XX tristate "LED support for Awinic AW20036/AW20054/AW20072/AW20108" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 2f170d69dcbf..983811384fec 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_LEDS_ADP5520) +=3D leds-adp5520.o obj-$(CONFIG_LEDS_AN30259A) +=3D leds-an30259a.o obj-$(CONFIG_LEDS_APU) +=3D leds-apu.o obj-$(CONFIG_LEDS_ARIEL) +=3D leds-ariel.o +obj-$(CONFIG_LEDS_AS3668) +=3D leds-as3668.o obj-$(CONFIG_LEDS_AW200XX) +=3D leds-aw200xx.o obj-$(CONFIG_LEDS_AW2013) +=3D leds-aw2013.o obj-$(CONFIG_LEDS_BCM6328) +=3D leds-bcm6328.o diff --git a/drivers/leds/leds-as3668.c b/drivers/leds/leds-as3668.c new file mode 100644 index 000000000000..b2794492370e --- /dev/null +++ b/drivers/leds/leds-as3668.c @@ -0,0 +1,202 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Osram AMS AS3668 LED Driver IC + * + * Copyright (C) 2025 Lukas Timmermann + */ + +#include +#include +#include +#include +#include + +#define AS3668_MAX_LEDS 4 + +/* Chip Ident */ + +#define AS3668_CHIP_ID1_REG 0x3e +#define AS3668_CHIP_ID 0xa5 + +/* Current Control */ + +#define AS3668_CURR_MODE_REG 0x01 +#define AS3668_CURR_MODE_OFF 0x0 +#define AS3668_CURR_MODE_ON 0x1 +#define AS3668_CURR1_MODE_MASK GENMASK(1, 0) +#define AS3668_CURR2_MODE_MASK GENMASK(3, 2) +#define AS3668_CURR3_MODE_MASK GENMASK(5, 4) +#define AS3668_CURR4_MODE_MASK GENMASK(7, 6) +#define AS3668_CURR1_REG 0x02 +#define AS3668_CURR2_REG 0x03 +#define AS3668_CURR3_REG 0x04 +#define AS3668_CURR4_REG 0x05 + +#define AS3668_CURR_MODE_PACK(mode) (((mode) << 0) | \ + ((mode) << 2) | \ + ((mode) << 4) | \ + ((mode) << 6)) + +struct as3668_led { + struct led_classdev cdev; + struct as3668 *chip; + struct fwnode_handle *fwnode; + u8 mode_mask; + u8 current_reg; +}; + +struct as3668 { + struct i2c_client *client; + struct as3668_led leds[AS3668_MAX_LEDS]; +}; + +static int as3668_channel_mode_set(struct as3668_led *led, u8 mode) +{ + int ret; + u8 channel_modes; + + ret =3D i2c_smbus_read_byte_data(led->chip->client, AS3668_CURR_MODE_REG); + if (ret < 0) { + dev_err(led->cdev.dev, "failed to read channel modes\n"); + return ret; + } + channel_modes =3D (u8)ret; + + channel_modes &=3D ~led->mode_mask; + channel_modes |=3D led->mode_mask & (AS3668_CURR_MODE_PACK(mode)); + + return i2c_smbus_write_byte_data(led->chip->client, AS3668_CURR_MODE_REG,= channel_modes); +} + +static enum led_brightness as3668_brightness_get(struct led_classdev *cdev) +{ + struct as3668_led *led =3D container_of(cdev, struct as3668_led, cdev); + + return i2c_smbus_read_byte_data(led->chip->client, led->current_reg); +} + +static void as3668_brightness_set(struct led_classdev *cdev, enum led_brig= htness brightness) +{ + struct as3668_led *led =3D container_of(cdev, struct as3668_led, cdev); + int err; + + err =3D as3668_channel_mode_set(led, !!brightness); + if (err) + dev_err(cdev->dev, "failed to set channel mode: %d\n", err); + + err =3D i2c_smbus_write_byte_data(led->chip->client, led->current_reg, br= ightness); + if (err) + dev_err(cdev->dev, "failed to set brightness: %d\n", err); +} + +static int as3668_dt_init(struct as3668 *as3668) +{ + struct device *dev =3D &as3668->client->dev; + struct as3668_led *led; + struct led_init_data init_data =3D {}; + int err; + u32 reg; + + for_each_available_child_of_node_scoped(dev_of_node(dev), child) { + err =3D of_property_read_u32(child, "reg", ®); + if (err) + return dev_err_probe(dev, err, "failed to read 'reg' property"); + + if (reg < 0 || reg >=3D AS3668_MAX_LEDS) + return dev_err_probe(dev, -EINVAL, + "unsupported LED: %d\n", reg); + + led =3D &as3668->leds[reg]; + led->fwnode =3D of_fwnode_handle(child); + + led->current_reg =3D reg + AS3668_CURR1_REG; + led->mode_mask =3D AS3668_CURR1_MODE_MASK << (reg * 2); + led->chip =3D as3668; + + led->cdev.max_brightness =3D U8_MAX; + led->cdev.brightness_get =3D as3668_brightness_get; + led->cdev.brightness_set =3D as3668_brightness_set; + + init_data.fwnode =3D led->fwnode; + init_data.default_label =3D ":"; + + err =3D devm_led_classdev_register_ext(dev, &led->cdev, &init_data); + if (err) + return dev_err_probe(dev, err, "failed to register LED %d\n", reg); + } + + return 0; +} + +static int as3668_probe(struct i2c_client *client) +{ + struct as3668 *as3668; + int err; + u8 chip_id; + + chip_id =3D i2c_smbus_read_byte_data(client, AS3668_CHIP_ID1_REG); + if (chip_id !=3D AS3668_CHIP_ID) + return dev_err_probe(&client->dev, -ENODEV, + "expected chip ID 0x%02x, got 0x%02x\n", + AS3668_CHIP_ID, chip_id); + + as3668 =3D devm_kzalloc(&client->dev, sizeof(*as3668), GFP_KERNEL); + if (!as3668) + return -ENOMEM; + + as3668->client =3D client; + + err =3D as3668_dt_init(as3668); + if (err) + return err; + + /* Set all four channel modes to 'off' */ + err =3D i2c_smbus_write_byte_data(client, AS3668_CURR_MODE_REG, + FIELD_PREP(AS3668_CURR1_MODE_MASK, AS3668_CURR_MODE_OFF) | + FIELD_PREP(AS3668_CURR2_MODE_MASK, AS3668_CURR_MODE_OFF) | + FIELD_PREP(AS3668_CURR3_MODE_MASK, AS3668_CURR_MODE_OFF) | + FIELD_PREP(AS3668_CURR4_MODE_MASK, AS3668_CURR_MODE_OFF)); + + /* Set initial currents to 0mA */ + err |=3D i2c_smbus_write_byte_data(client, AS3668_CURR1_REG, 0); + err |=3D i2c_smbus_write_byte_data(client, AS3668_CURR2_REG, 0); + err |=3D i2c_smbus_write_byte_data(client, AS3668_CURR3_REG, 0); + err |=3D i2c_smbus_write_byte_data(client, AS3668_CURR4_REG, 0); + + if (err) + return dev_err_probe(&client->dev, -EIO, "failed to set zero initial cur= rent levels\n"); + + return 0; +} + +static void as3668_remove(struct i2c_client *client) +{ + i2c_smbus_write_byte_data(client, AS3668_CURR_MODE_REG, 0); +} + +static const struct i2c_device_id as3668_idtable[] =3D { + { "as3668" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, as3668_idtable); + +static const struct of_device_id as3668_match_table[] =3D { + { .compatible =3D "ams,as3668" }, + { } +}; +MODULE_DEVICE_TABLE(of, as3668_match_table); + +static struct i2c_driver as3668_driver =3D { + .driver =3D { + .name =3D "leds_as3668", + .of_match_table =3D as3668_match_table, + }, + .probe =3D as3668_probe, + .remove =3D as3668_remove, + .id_table =3D as3668_idtable, +}; +module_i2c_driver(as3668_driver); + +MODULE_AUTHOR("Lukas Timmermann "); +MODULE_DESCRIPTION("AS3668 LED driver"); +MODULE_LICENSE("GPL"); --=20 2.52.0