From nobody Fri Dec 19 20:32:37 2025 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 1558B1C861D; Wed, 4 Jun 2025 23:06:06 +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=1749078370; cv=none; b=Kal+AmAY9Ek2X9UzlTdurn0LrIj9VDf2BE2qK8FQDMLRuP+2oWrJ10iRZr790NhTEk3VhjN1IH6hoQ31O5StmG92i7hXC8CLewXdTLt9HlVQY7Vie1Zws2QaH12CcLF8YihVQwlzlzdkztd2rHxu+lJpuqFKaZ6WgaUSsEdxGk0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749078370; c=relaxed/simple; bh=fGU4lugVF4Bpu4xfcP91GoGT8zpqIcXZyqwfIW/XkfY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=txMUzMyOP8341eZvrejhq9dmSX3FuicvAprgLnyHqMk3LR2PsW1Z5MQ9zjqV4H1RsbCUAU0aMOSQctFarpjxgwwDTUi7qVd9m22cL42SMhLJxjrRiO4hHR8F2Bk/buVc6OySKxVSfrXXdqLVOOfXc56SFC5WpQ/3FNF3EMM96M4= 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 smtp2.mailbox.org (smtp2.mailbox.org [IPv6:2001:67c:2050:b231:465::2]) (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 4bCNLn14Qmz9spq; Thu, 5 Jun 2025 00:59:29 +0200 (CEST) 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 v3 1/2] leds: as3668: Driver for the ams Osram 4-channel i2c LED driver Date: Thu, 5 Jun 2025 00:58:37 +0200 Message-ID: <20250604225838.102910-2-linux@timmermann.space> In-Reply-To: <20250604225838.102910-1-linux@timmermann.space> References: <20250604225838.102910-1-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 X-Rspamd-Queue-Id: 4bCNLn14Qmz9spq Content-Type: text/plain; charset="utf-8" This is the actual driver for the as3668. There were no related drivers in the kernel until now,=20 so I created a new file. I've checked around for relatives=20 of the as3668 but all of them are quite different, which is why wrote the driver just for the as3668. Signed-off-by: Lukas Timmermann --- MAINTAINERS | 6 ++ drivers/leds/Kconfig | 14 +++ drivers/leds/Makefile | 1 + drivers/leds/leds-as3668.c | 196 +++++++++++++++++++++++++++++++++++++ 4 files changed, 217 insertions(+) create mode 100644 drivers/leds/leds-as3668.c diff --git a/MAINTAINERS b/MAINTAINERS index c59316109e3f..5929c158a0e2 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: drivers/leds/leds-as3668.c + ASAHI KASEI AK7375 LENS VOICE COIL DRIVER M: Tianshu Qiu L: linux-media@vger.kernel.org diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index a104cbb0a001..3fe7a0e98140 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -100,6 +100,20 @@ config LEDS_ARIEL =20 Say Y to if your machine is a Dell Wyse 3020 thin client. =20 +config LEDS_AS3668 + tristate "LED support for AMS AS3668" + depends on LEDS_CLASS + depends on I2C + help + This option enables support for the 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..e3f90078f6ec --- /dev/null +++ b/drivers/leds/leds-as3668.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Osram AMS AS3668 LED Driver IC + * + * Copyright (C) 2025 Lukas Timmermann + */ + +#include +#include +#include +#include + +#define AS3668_MAX_LEDS 4 + +/* Chip Registers */ +#define AS3668_CHIP_ID1 0x3e +#define AS3668_CHIP_ID2 0x3f + +#define AS3668_CHIP_ID2_SERIAL_MASK GENMASK(7, 4) +#define AS3668_CHIP_ID2_REV_MASK GENMASK(3, 0) + +#define AS3668_CURRX_CONTROL 0x01 +#define AS3668_CURR1 0x02 +#define AS3668_CURR2 0x03 +#define AS3668_CURR3 0x04 +#define AS3668_CURR4 0x05 + +/* Constants */ +#define AS3668_CHIP_IDENT 0xa5 +#define AS3668_CHIP_REV1 0x01 + +struct as3668_led { + struct led_classdev cdev; + struct as3668 *chip; + struct fwnode_handle *fwnode; + + int num; +}; + +struct as3668 { + struct i2c_client *client; + struct as3668_led leds[AS3668_MAX_LEDS]; +}; + +static int as3668_read_value(struct i2c_client *client, u8 reg) +{ + return i2c_smbus_read_byte_data(client, reg); +} + +static int as3668_write_value(struct i2c_client *client, u8 reg, u8 value) +{ + int err =3D i2c_smbus_write_byte_data(client, reg, value); + + if (err) + dev_err(&client->dev, "error writing to reg 0x%tx, returned %d", reg, er= r); + + return err; +} + +static enum led_brightness as3668_brightness_get(struct led_classdev *cdev) +{ + struct as3668_led *led =3D container_of(cdev, struct as3668_led, cdev); + + return as3668_read_value(led->chip->client, AS3668_CURR1 + led->num); +} + +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); + + as3668_write_value(led->chip->client, AS3668_CURR1 + led->num, brightness= ); +} + +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; + int i =3D 0; + + for_each_available_child_of_node_scoped(dev_of_node(dev), child) { + err =3D of_property_read_u32(child, "reg", ®); + if (err) + dev_err(dev, "unable to read device tree led reg, err %d", err); + + i =3D reg; + + if (i < 0 || i > AS3668_MAX_LEDS) { + dev_err(dev, "unsupported led reg %d\n", i); + return -EOPNOTSUPP; + } + + led =3D &as3668->leds[i]; + led->fwnode =3D of_fwnode_handle(child); + + led->num =3D i; + 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) { + dev_err(dev, "failed to register %d LED\n", i); + return err; + } + } + + return 0; +} + +static int as3668_probe(struct i2c_client *client) +{ + u8 chip_id1, chip_id2, chip_serial, chip_rev; + struct as3668 *as3668; + + /* Check for sensible i2c address */ + if (client->addr !=3D 0x42) + return dev_err_probe(&client->dev, -EFAULT, + "unexpected address for as3668 device\n"); + + /* Read identifier from chip */ + chip_id1 =3D as3668_read_value(client, AS3668_CHIP_ID1); + + if (chip_id1 !=3D AS3668_CHIP_IDENT) + return dev_err_probe(&client->dev, -ENODEV, + "chip reported wrong id: 0x%tx\n", chip_id1); + + /* Check the revision*/ + chip_id2 =3D as3668_read_value(client, AS3668_CHIP_ID2); + chip_serial =3D FIELD_GET(AS3668_CHIP_ID2_SERIAL_MASK, chip_id2); + chip_rev =3D FIELD_GET(AS3668_CHIP_ID2_REV_MASK, chip_id2); + + if (chip_rev !=3D AS3668_CHIP_REV1) + dev_warn(&client->dev, "unexpected chip revision\n"); + + /* Print out information about the chip */ + dev_dbg(&client->dev, + "chip_id: 0x%tx | chip_id2: 0x%tx | chip_serial: 0x%tx | chip_rev: 0x%tx= \n", + chip_id1, chip_id2, chip_serial, chip_rev); + + as3668 =3D devm_kzalloc(&client->dev, struct_size(as3668, leds, AS3668_MA= X_LEDS), GFP_KERNEL); + as3668->client =3D client; + + as3668_dt_init(as3668); + + /* Initialize the chip */ + as3668_write_value(client, AS3668_CURRX_CONTROL, 0x55); + as3668_write_value(client, AS3668_CURR1, 0x00); + as3668_write_value(client, AS3668_CURR2, 0x00); + as3668_write_value(client, AS3668_CURR3, 0x00); + as3668_write_value(client, AS3668_CURR4, 0x00); + + return 0; +} + +static void as3668_remove(struct i2c_client *client) +{ + as3668_write_value(client, AS3668_CURRX_CONTROL, 0x0); +} + +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 2.49.0