From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f172.google.com (mail-qk1-f172.google.com [209.85.222.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7CEFE375F81 for ; Mon, 18 May 2026 15:21:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779117682; cv=none; b=KzuYpm38ermSQEbXr20U5KZ3DInlfqBL7Zcc0vEs4F+49kv9uj1HfnqK0yCzCh9/gKjLND47paIh7ZWfYcziBv2AdHPGomrtYPAsoql3A3f4O9O8x87p1T0aoGVz2WxCY8sfZHqaUxV0u0PaybNXg98dtX2MDJKa+aAeRvRJwnY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779117682; c=relaxed/simple; bh=9QB+FL+8fOgHPAf3VOjSBEfCH8eYqep9G1Eqn0HgZ68=; h=From:Date:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EkeNxQN2pi5VfbGwLSfSTPMbiInPtSBzOiUgYC3hwV1Bb6LsLxmz8OBWjVMOGIlKw/IaTQ/ffxpGz6P5Pd4Y5xhCBif+ucQ2tt8sErqc9TO5JgeHQJx6qAsrJZ0JA/lIs2c0LaEQnxVcUcUKwq9IhfGoEPMR8dzN3/vuozFJR6c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=WgxgF4Kq; arc=none smtp.client-ip=209.85.222.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WgxgF4Kq" Received: by mail-qk1-f172.google.com with SMTP id af79cd13be357-90d1f03238bso336565785a.1 for ; Mon, 18 May 2026 08:21:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779117679; x=1779722479; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=7mKc9VNZ1T4lw9dkqyOvvk8GIHq3GkLIAs6uk7WRC3A=; b=WgxgF4Kqdx24jdIV5/N3f7BA2liX0IYe1yxCIBnjNr8rT8yVC7e4Oxf50p8Btfc1E1 6ob3iZdi1+80fO5MT+Ndx7mAhwfa0tTwM68nPs4MRITffUIeH71U6C20a+xl+a7tXuoh fShLUc6iWVPEN2pjR3eKxxW3XJL7D3sB+I0/rBhOt299HxLYH3MjWqaRUabjtQtcDZKT giDwl37ar+UrdR0lq66YZCKoWy0FH090+QLhx8O/u246cRw1Urm5rRFyuonCUyl2CrF3 e1Kcm77yb4DDxnyocD4txS6Wfyg/PxR9E0CoWC3uFCa4tP1q1FN+JnzrHorW4aoVee+G lhyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779117679; x=1779722479; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=7mKc9VNZ1T4lw9dkqyOvvk8GIHq3GkLIAs6uk7WRC3A=; b=aNUN2FzsR5TEirj/sZ089l9sla/yQbxzSQUmQmEoBLOATrfsKn416YsA/20Af4KUK5 HeHbKT2rqo1uIM0OoQ/v3wjIMlh8roiSC29eFIdiUj/phvIi2B3YRrTG+5VEbgKzN6hd d4doXgcfOZJJbvwgReySFwCA0dU69J2etqR2JFzkw39X8MGCy8j1U/pt8nmCO16UkqIp BLOIG3DcLk8FTBSHNBTV4/cj2n2AqyiEU8PVj6j0Fx2nDNYnWU9DPTflFeo8RSgftgKs FGGWXbEe5VKzpiRRbVunzP7LCOvYcHPq3mY60w0cuW6kbnraRIhKeeVRSaUgG0o4fzVQ +/bg== X-Forwarded-Encrypted: i=1; AFNElJ9pKMLLBRLvvZI3jW+hRVOviT6N8/9KpWydUkFaVG0x9YIdjym/dW7mUdNyvG+lFpS0pui5beuGB80t24Y=@vger.kernel.org X-Gm-Message-State: AOJu0YxneXPV+JA1bhAQcrg2DMn5OmbhAERESpjfZThNPRQQb9bLZ3rr 2B0yIt7dIu521t0FUh/r8p0carfI8eDtnnFwKyHt5MLZY03IS42a1gtj X-Gm-Gg: Acq92OHTlTIoKgAlzyV6KG0sXk+5bzxwHbdNtT150qSMhyZP+VNl8TC7sxVelkAN0te UvvJ78OvAL/N2tLbcqTqHuZ7NG0M/uOYyZebTZNIgYuNwSgWO9DVa5Da9ggwIZvFtOj8RpZup55 7lUtN+MryPiO6OPO2w2uLQj/T3XahoHHptgUaw6SA+xoYprc0vVArLo0E6buLcAcnxpglJy5Xyf 06Q25U79ORY4AfMR0gDSR670fjhKhiq3c5AafWJ4qcHmc1MDR4qck094XbmGilxijyjJ204Eih/ fzakldFpHkZsgzlKcvzxPvJQXw3/BNqSji1jPixMgweaZDlkHoSiVWLCFYkhEwo34OsjsTycTIF WBnCMSRiYZ8kqjw70uF0p1PS6IvXxyvqj+DnXyt1cAi1iwwTugTFDrRQ9NTYyws79mubVJsGxlU TK3mN+H/I2uQQgoInzOg5kgKLUzgb/nRA9 X-Received: by 2002:a05:620a:17a6:b0:911:4885:9112 with SMTP id af79cd13be357-91148859a45mr2266099085a.2.1779117679224; Mon, 18 May 2026 08:21:19 -0700 (PDT) Received: from localhost ([2804:30c:1f02:6000:8b59:7c96:762e:9faa]) by smtp.gmail.com with ESMTPSA id af79cd13be357-91433530506sm425651585a.44.2026.05.18.08.21.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 May 2026 08:21:18 -0700 (PDT) From: Marcelo Schmitt X-Google-Original-From: Marcelo Schmitt Date: Mon, 18 May 2026 12:21:33 -0300 To: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Cc: jic23@kernel.org, nuno.sa@analog.com, Michael.Hennerich@analog.com, dlechner@baylibre.com, andy@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, marcelo.schmitt1@gmail.com Subject: [PATCH v1 2/4] iio: adc: Add support for LTC2378-20 and similar ADCs Message-ID: <301e4fc7544a485b56e7a8b91c3b66f5ac98e842.1779117444.git.marcelo.schmitt1@gmail.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: From: Marcelo Schmitt Initial support for LTC2378-20 and similar analog-to-digital converters. Signed-off-by: Marcelo Schmitt --- The data union for the sample data and the filling of IIO channel scan_type struct could probably have been avoided and postponed. Though, that would probably imply larger git diffs in the buffer patches so I added those earlier to minimize diff size in the buffer patches. MAINTAINERS | 1 + drivers/iio/adc/Kconfig | 12 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ltc2378.c | 352 ++++++++++++++++++++++++++++++++++++++ drivers/iio/adc/ltc2378.h | 48 ++++++ 5 files changed, 414 insertions(+) create mode 100644 drivers/iio/adc/ltc2378.c create mode 100644 drivers/iio/adc/ltc2378.h diff --git a/MAINTAINERS b/MAINTAINERS index 768f56eea476..d9a772ac599c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15201,6 +15201,7 @@ L: linux-iio@vger.kernel.org S: Supported W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/iio/adc/adi,ltc2378.yaml +F: drivers/iio/adc/ltc2378* LTC2664 IIO DAC DRIVER M: Michael Hennerich diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 8550917226a1..70fec8e3e891 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -939,6 +939,18 @@ config LTC2309 This driver can also be built as a module. If so, the module will be called ltc2309. +config LTC2378 + tristate "Analog Devices LTC2378 ADC driver" + depends on SPI + depends on GPIOLIB || PWM + select IIO_BUFFER + help + Say yes here to build support for Analog Devices LTC2378-20 and + similar analog to digital converters. + + This driver can also be built as a module. If so, the module will + be called ltc2378. + config LTC2471 tristate "Linear Technology LTC2471 and LTC2473 ADC driver" depends on I2C diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 707dd708912f..1814fb78dde3 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -81,6 +81,7 @@ obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o obj-$(CONFIG_LTC2309) += ltc2309.o +obj-$(CONFIG_LTC2378) += ltc2378.o obj-$(CONFIG_LTC2471) += ltc2471.o obj-$(CONFIG_LTC2485) += ltc2485.o obj-$(CONFIG_LTC2496) += ltc2496.o ltc2497-core.o diff --git a/drivers/iio/adc/ltc2378.c b/drivers/iio/adc/ltc2378.c new file mode 100644 index 000000000000..7916500c470c --- /dev/null +++ b/drivers/iio/adc/ltc2378.c @@ -0,0 +1,352 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Analog Devices LTC2378 ADC series driver + * + * Copyright (C) 2026 Analog Devices Inc. + * Author: Ioan-Daniel Pop + * Author: Marcelo Schmitt + */ + +#include +#include +#include +#include +#include + +#include "ltc2378.h" + +enum ltc2378_supported_device_ids { + ID_LTC2338_18, + ID_LTC2364_16, + ID_LTC2364_18, + ID_LTC2367_16, + ID_LTC2367_18, + ID_LTC2368_16, + ID_LTC2368_18, + ID_LTC2369_18, + ID_LTC2370_16, + ID_LTC2376_16, + ID_LTC2376_18, + ID_LTC2376_20, + ID_LTC2377_16, + ID_LTC2377_18, + ID_LTC2377_20, + ID_LTC2378_16, + ID_LTC2378_18, + ID_LTC2378_20, + ID_LTC2379_18, + ID_LTC2380_16, +}; + +static const struct ltc2378_chip_info ltc2378_chip_info[] = { + [ID_LTC2338_18] = { + .name = "ltc2338-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2364_16] = { + .name = "ltc2364-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2364_18] = { + .name = "ltc2364-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2367_16] = { + .name = "ltc2367-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2367_18] = { + .name = "ltc2367-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2368_16] = { + .name = "ltc2368-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2368_18] = { + .name = "ltc2368-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2369_18] = { + .name = "ltc2369-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2370_16] = { + .name = "ltc2370-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_UNSIGNED_INT, + }, + [ID_LTC2376_16] = { + .name = "ltc2376-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2376_18] = { + .name = "ltc2376-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2376_20] = { + .name = "ltc2376-20", + .resolution = 20, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2377_16] = { + .name = "ltc2377-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2377_18] = { + .name = "ltc2377-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2377_20] = { + .name = "ltc2377-20", + .resolution = 20, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2378_16] = { + .name = "ltc2378-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2378_18] = { + .name = "ltc2378-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2378_20] = { + .name = "ltc2378-20", + .resolution = 20, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2379_18] = { + .name = "ltc2379-18", + .resolution = 18, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, + [ID_LTC2380_16] = { + .name = "ltc2380-16", + .resolution = 16, + .out_format = IIO_SCAN_FORMAT_SIGNED_INT, + }, +}; + +static int ltc2378_convert_and_acquire(struct ltc2378_state *st) +{ + int ret; + + /* Cause a rising edge of CNV to initiate a new ADC conversion */ + gpiod_set_value_cansleep(st->cnv_gpio, 1); + ret = spi_sync_transfer(st->spi, &st->xfer, 1); + gpiod_set_value_cansleep(st->cnv_gpio, 0); + + return ret; +} + +static int ltc2378_channel_single_read(const struct iio_chan_spec *chan, + struct ltc2378_state *st, int *val) +{ + const struct iio_scan_type *scan_type = &chan->scan_type; + u32 sample; + int ret; + + ret = ltc2378_convert_and_acquire(st); + if (ret) + return ret; + + if (scan_type->endianness == IIO_BE) { + if (scan_type->realbits > 16) + sample = be32_to_cpu(st->scan.data.sample_buf32_be); + else + sample = be16_to_cpu(st->scan.data.sample_buf16_be); + } else { + if (scan_type->realbits > 16) + sample = st->scan.data.sample_buf32; + else + sample = st->scan.data.sample_buf16; + } + + sample >>= scan_type->shift; + + if (scan_type->format == IIO_SCAN_FORMAT_SIGNED_INT) + *val = sign_extend32(sample, scan_type->realbits - 1); + else + *val = sample; + + return 0; +} + +static int ltc2378_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + int *val, int *val2, long info) +{ + struct ltc2378_state *st = iio_priv(indio_dev); + int ret; + + switch (info) { + case IIO_CHAN_INFO_RAW: + IIO_DEV_ACQUIRE_DIRECT_MODE(indio_dev, claim); + if (IIO_DEV_ACQUIRE_FAILED(claim)) + return -EBUSY; + + ret = ltc2378_channel_single_read(chan, st, val); + if (ret) + return ret; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + *val = st->ref_uV / MILLI; + /* + * For all LTC2378-like devices, the amount of bits that express + * voltage magnitude depend on the output code format: + * - straight binary: All precision/resolution bits are used. + * - 2's complement: One of the precision bits is used for sign. + */ + if (st->info->out_format == IIO_SCAN_FORMAT_SIGNED_INT) + *val2 = st->info->resolution - 1; + else + *val2 = st->info->resolution; + + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +static const struct iio_info ltc2378_iio_info = { + .read_raw = <c2378_read_raw, +}; + +static int ltc2378_probe(struct spi_device *spi) +{ + struct iio_chan_spec *ltc2378_chan; + struct device *dev = &spi->dev; + unsigned int num_iio_chans = 1; + struct iio_dev *indio_dev; + struct ltc2378_state *st; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi = spi; + + st->ref_uV = devm_regulator_get_enable_read_voltage(dev, "ref"); + if (st->ref_uV < 0) + return dev_err_probe(dev, -ENODEV, "failed to read ref regulator\n"); + + st->info = spi_get_device_match_data(spi); + if (!st->info) + return -EINVAL; + + indio_dev->name = st->info->name; + indio_dev->info = <c2378_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + st->cnv_gpio = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_LOW); + if (st->cnv_gpio && IS_ERR(st->cnv_gpio)) + return dev_err_probe(dev, PTR_ERR(st->cnv_gpio), + "failed to get CNV GPIO"); + + ltc2378_chan = devm_kzalloc(&spi->dev, sizeof(struct iio_chan_spec), GFP_KERNEL); + if (!ltc2378_chan) + return -ENOMEM; + + *ltc2378_chan = (struct iio_chan_spec) { + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .scan_type = { + .format = st->info->out_format, + .realbits = st->info->resolution, + .storagebits = st->info->resolution > 16 ? 32 : 16, + .shift = st->info->resolution > 16 ? 8 : 0, + .endianness = IIO_BE, + }, + }; + st->xfer.rx_buf = &st->scan.data; + st->xfer.len = BITS_TO_BYTES(ltc2378_chan->scan_type.storagebits); + + indio_dev->channels = ltc2378_chan; + indio_dev->num_channels = num_iio_chans; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id ltc2378_of_match[] = { + { .compatible = "adi,ltc2338-18", .data = <c2378_chip_info[ID_LTC2338_18] }, + { .compatible = "adi,ltc2364-16", .data = <c2378_chip_info[ID_LTC2364_16] }, + { .compatible = "adi,ltc2364-18", .data = <c2378_chip_info[ID_LTC2364_18] }, + { .compatible = "adi,ltc2367-16", .data = <c2378_chip_info[ID_LTC2367_16] }, + { .compatible = "adi,ltc2367-18", .data = <c2378_chip_info[ID_LTC2367_18] }, + { .compatible = "adi,ltc2368-16", .data = <c2378_chip_info[ID_LTC2368_16] }, + { .compatible = "adi,ltc2368-18", .data = <c2378_chip_info[ID_LTC2368_18] }, + { .compatible = "adi,ltc2369-18", .data = <c2378_chip_info[ID_LTC2369_18] }, + { .compatible = "adi,ltc2370-16", .data = <c2378_chip_info[ID_LTC2370_16] }, + { .compatible = "adi,ltc2376-16", .data = <c2378_chip_info[ID_LTC2376_16] }, + { .compatible = "adi,ltc2376-18", .data = <c2378_chip_info[ID_LTC2376_18] }, + { .compatible = "adi,ltc2376-20", .data = <c2378_chip_info[ID_LTC2376_20] }, + { .compatible = "adi,ltc2377-16", .data = <c2378_chip_info[ID_LTC2377_16] }, + { .compatible = "adi,ltc2377-18", .data = <c2378_chip_info[ID_LTC2377_18] }, + { .compatible = "adi,ltc2377-20", .data = <c2378_chip_info[ID_LTC2377_20] }, + { .compatible = "adi,ltc2378-16", .data = <c2378_chip_info[ID_LTC2378_16] }, + { .compatible = "adi,ltc2378-18", .data = <c2378_chip_info[ID_LTC2378_18] }, + { .compatible = "adi,ltc2378-20", .data = <c2378_chip_info[ID_LTC2378_20] }, + { .compatible = "adi,ltc2379-18", .data = <c2378_chip_info[ID_LTC2379_18] }, + { .compatible = "adi,ltc2380-16", .data = <c2378_chip_info[ID_LTC2380_16] }, + { }, +}; +MODULE_DEVICE_TABLE(of, ltc2378_of_match); + +static const struct spi_device_id ltc2378_spi_id[] = { + { "ltc2338-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2338_18] }, + { "ltc2364-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2364_16] }, + { "ltc2364-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2364_18] }, + { "ltc2367-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2367_16] }, + { "ltc2367-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2367_18] }, + { "ltc2368-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2368_16] }, + { "ltc2368-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2368_18] }, + { "ltc2369-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2369_18] }, + { "ltc2370-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2370_16] }, + { "ltc2376-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2376_16] }, + { "ltc2376-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2376_18] }, + { "ltc2376-20", (kernel_ulong_t)<c2378_chip_info[ID_LTC2376_20] }, + { "ltc2377-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2377_16] }, + { "ltc2377-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2377_18] }, + { "ltc2377-20", (kernel_ulong_t)<c2378_chip_info[ID_LTC2377_20] }, + { "ltc2378-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2378_16] }, + { "ltc2378-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2378_18] }, + { "ltc2378-20", (kernel_ulong_t)<c2378_chip_info[ID_LTC2378_20] }, + { "ltc2379-18", (kernel_ulong_t)<c2378_chip_info[ID_LTC2379_18] }, + { "ltc2380-16", (kernel_ulong_t)<c2378_chip_info[ID_LTC2380_16] }, + { }, +}; +MODULE_DEVICE_TABLE(spi, ltc2378_spi_id); + +static struct spi_driver ltc2378_driver = { + .driver = { + .name = "ltc2378", + .of_match_table = ltc2378_of_match + }, + .probe = ltc2378_probe, + .id_table = ltc2378_spi_id, +}; +module_spi_driver(ltc2378_driver); + +MODULE_AUTHOR("Ioan-Daniel Pop "); +MODULE_AUTHOR("Marcelo Schmitt "); +MODULE_DESCRIPTION("Analog Devices LTC2378 ADC series driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/iio/adc/ltc2378.h b/drivers/iio/adc/ltc2378.h new file mode 100644 index 000000000000..515f7e8a4f2e --- /dev/null +++ b/drivers/iio/adc/ltc2378.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Analog Devices LTC2378 and similar ADCs common definitions and properties + * Copyright (C) 2026 Analog Devices, Inc. + * Author: Marcelo Schmitt + */ + +#ifndef __DRIVERS_IIO_ADC_LTC2378_H__ +#define __DRIVERS_IIO_ADC_LTC2378_H__ + +#include +#include +#include +#include + +#define LTC2378_TDSDOBUSYL_NS 5 +#define LTC2378_TBUSYLH_NS 13 +#define LTC2378_TCNV_HIGH_NS 20 + +struct ltc2378_chip_info { + const char *name; + int resolution; + const char out_format; +}; + +struct ltc2378_state { + const struct ltc2378_chip_info *info; + struct gpio_desc *cnv_gpio; + struct spi_device *spi; + struct spi_transfer xfer; + int ref_uV; + + /* + * DMA (thus cache coherency maintenance) requires the + * transfer buffers to live in their own cache lines. + */ + struct { + union { + __be16 sample_buf16_be; + __be32 sample_buf32_be; + u16 sample_buf16; + u32 sample_buf32; + } data; + aligned_s64 timestamp; + } scan __aligned(IIO_DMA_MINALIGN); +}; + +#endif /* __DRIVERS_IIO_ADC_LTC2378_H__ */ -- 2.53.0