From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 239D5481AE for ; Wed, 20 Dec 2023 15:22:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="K2DdV+XW" Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id ACD606100F for ; Wed, 20 Dec 2023 15:22:27 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org ACD606100F Authentication-Results: smtp3.osuosl.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=K2DdV+XW X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -2.099 X-Spam-Level: Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id A7UR1HVdLdmb for ; Wed, 20 Dec 2023 15:22:26 +0000 (UTC) Received: from mail-ot1-x329.google.com (mail-ot1-x329.google.com [IPv6:2607:f8b0:4864:20::329]) by smtp3.osuosl.org (Postfix) with ESMTPS id 5B7EF600CB for ; Wed, 20 Dec 2023 15:22:26 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 5B7EF600CB Received: by mail-ot1-x329.google.com with SMTP id 46e09a7af769-6da3659535fso4897172a34.3 for ; Wed, 20 Dec 2023 07:22:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1703085745; x=1703690545; darn=lists.linuxfoundation.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=BNhR0jjyUXnJtDUmjrC6hxZFLVqudwmmtFtsktcySwI=; b=K2DdV+XWO7usAqwvNlg/WdVUUOlL73/B0DLeLDQMbl0uQeYWe19QAWyZ2VjxaNxmHW nbLdtVD/jp+Pl1PYJZqdbOp6KhYm/rACptQHQwTi6OrW5AbbVn6ok+poSeshbP9bNc70 JY6F83TYAEoYh5BU9bm58CZNK8CXxzmlm2R6K0W8eVVcraK/gojdpQET4geUQ7yI9Qim eyvaMppwzPLTjqATKHadglICYCv5qGMNNxRK0o87l65udt68Ujz3ygu/83GYEICFGCiI WOlrSs4M5gNtXMp1EMXfKQDQPq8jD0HX8hFPX6dcJf+mtnpGjAG960eZwvlikTEX+7vp 09LQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703085745; x=1703690545; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=BNhR0jjyUXnJtDUmjrC6hxZFLVqudwmmtFtsktcySwI=; b=Y+77EC6VFYu6FDoLHF3JuOVlPyXgUfwPWlaz8reA9DLwKKabcxEswaOx5b26YeRplH hqqKkKKwQlVvukA53qkFBaE7bsVq6sChSm/5dUsnAs6G0z0mhMK8+2dW6cs0Mjp/pBlL IPma4p/XPRcSUjUzOc8Wt/qffkEX7IWOnh0OLMZKh4tVkzj3RROjQNgZsxPZCea2JN6O 7x05FfN2w99JtktmVeNB201oOFBzOlLHL6aBr2c9lHPQTIbANRUYUhr03Z49RcFLa709 PtGveUypJNpVIxPkxsFtWSyRahdGmsRKMtNaAVxKeuoqKxYiCJ2VhlMB+mAGuRXLFHxU DsGA== X-Gm-Message-State: AOJu0Yxk9SD34MoiyViH3T4TahxTNPH7lsedJ138a9iqlB/aYqjz24UT rkPy3oMRBl7b31XTmWwKnlA= X-Google-Smtp-Source: AGHT+IEbjkqkM2M3cPLRylyTHGL1WP1CRzWx2a4/K7e7cpDxNuJEfniXA4pFGs64pU8Bu3o1Lulfhw== X-Received: by 2002:a05:6358:7f07:b0:170:f1bd:30e2 with SMTP id p7-20020a0563587f0700b00170f1bd30e2mr14803008rwn.34.1703085745120; Wed, 20 Dec 2023 07:22:25 -0800 (PST) Received: from localhost.localdomain ([2401:4900:581e:798e:871c:98db:5638:a4]) by smtp.gmail.com with ESMTPSA id 13-20020a63164d000000b005cd835182c5sm7304724pgw.79.2023.12.20.07.22.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Dec 2023 07:22:24 -0800 (PST) From: Anshul Dalal To: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, devicetree@vger.kernel.org Cc: Anshul Dalal , Conor Dooley , Lars-Peter Clausen , Jonathan Cameron , Rob Herring , Krzysztof Kozlowski , linux-kernel-mentees@lists.linuxfoundation.org, Shuah Khan Subject: [PATCH v5 2/2] iio: dac: driver for MCP4821 Date: Wed, 20 Dec 2023 20:49:53 +0530 Message-ID: <20231220151954.154595-2-anshulusr@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231220151954.154595-1-anshulusr@gmail.com> References: <20231220151954.154595-1-anshulusr@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel-mentees@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Adds driver for the MCP48xx series of DACs. Device uses a simplex SPI channel. To set the value of an output channel, a 16-bit data of following format must be written: Bit field | Description 15 [MSB] | Channel selection bit 0 -> Channel A 1 -> Channel B 13 | Output Gain Selection bit 0 -> 2x Gain (Vref = 4.096V) 1 -> 1x Gain (Vref = 2.048V) 12 | Output Shutdown Control bit 0 -> Shutdown the selected channel 1 -> Active mode operation 11-0 [LSB]| DAC Input Data bits Value's big endian representation is taken as input for the selected DAC channel. For devices with a resolution of less than 12-bits, only the x most significant bits are considered where x is the resolution of the device. Reference: Page#22 [MCP48x2 Datasheet] Supported devices: +---------+--------------+-------------+ | Device | Resolution | Channels | |---------|--------------|-------------| | MCP4801 | 8-bit | 1 | | MCP4802 | 8-bit | 2 | | MCP4811 | 10-bit | 1 | | MCP4812 | 10-bit | 2 | | MCP4821 | 12-bit | 1 | | MCP4822 | 12-bit | 2 | +---------+--------------+-------------+ Devices tested: MCP4821 [12-bit single channel] MCP4802 [8-bit dual channel] Tested on Raspberry Pi Zero 2W Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/22244B.pdf #MCP48x1 Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/20002249B.pdf #MCP48x2 Signed-off-by: Anshul Dalal --- Changes for v5: - Removed unnecessary mutex - Removed unused channel fields initializations - Use saperate checks for validity of val and val2 in write_raw - Use cpu_to_be16 instead of put_unaligned_be16 Changes for v3,4: - no updates Changes for v2: - Changed device ordering to numerical - Fixed ordering of headers - Added struct mcp4821_chip_info instead of relying on driver_data from spi device ids - Use scoped_guards for all mutex locks - Changed write_val from __be16 to u16 in mcp4821_write_raw Fixes sparse warning: incorrect type in assignment Previous versions: v4: https://lore.kernel.org/lkml/20231219090252.818754-2-anshulusr@gmail.com/ v3: https://lore.kernel.org/lkml/20231218164735.787199-2-anshulusr@gmail.com/ v2: https://lore.kernel.org/lkml/20231217180836.584828-2-anshulusr@gmail.com/ v1: https://lore.kernel.org/lkml/20231117073040.685860-2-anshulusr@gmail.com/ --- MAINTAINERS | 7 ++ drivers/iio/dac/Kconfig | 10 ++ drivers/iio/dac/Makefile | 1 + drivers/iio/dac/mcp4821.c | 219 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 237 insertions(+) create mode 100644 drivers/iio/dac/mcp4821.c diff --git a/MAINTAINERS b/MAINTAINERS index 81d5fc0bba68..8d9274c33c6e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13029,6 +13029,13 @@ F: Documentation/ABI/testing/sysfs-bus-iio-potentiometer-mcp4531 F: drivers/iio/potentiometer/mcp4018.c F: drivers/iio/potentiometer/mcp4531.c +MCP4821 DAC DRIVER +M: Anshul Dalal +L: linux-iio@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/iio/dac/microchip,mcp4821.yaml +F: drivers/iio/dac/mcp4821.c + MCR20A IEEE-802.15.4 RADIO DRIVER M: Stefan Schmidt L: linux-wpan@vger.kernel.org diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 93b8be183de6..34eb40bb9529 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -400,6 +400,16 @@ config MCP4728 To compile this driver as a module, choose M here: the module will be called mcp4728. +config MCP4821 + tristate "MCP4801/02/11/12/21/22 DAC driver" + depends on SPI + help + Say yes here to build the driver for the Microchip MCP4801 + MCP4802, MCP4811, MCP4812, MCP4821 and MCP4822 DAC devices. + + To compile this driver as a module, choose M here: the module + will be called mcp4821. + config MCP4922 tristate "MCP4902, MCP4912, MCP4922 DAC driver" depends on SPI diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index 5b2bac900d5a..55bf89739d14 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -42,6 +42,7 @@ obj-$(CONFIG_MAX5522) += max5522.o obj-$(CONFIG_MAX5821) += max5821.o obj-$(CONFIG_MCP4725) += mcp4725.o obj-$(CONFIG_MCP4728) += mcp4728.o +obj-$(CONFIG_MCP4821) += mcp4821.o obj-$(CONFIG_MCP4922) += mcp4922.o obj-$(CONFIG_STM32_DAC_CORE) += stm32-dac-core.o obj-$(CONFIG_STM32_DAC) += stm32-dac.o diff --git a/drivers/iio/dac/mcp4821.c b/drivers/iio/dac/mcp4821.c new file mode 100644 index 000000000000..028983f59cda --- /dev/null +++ b/drivers/iio/dac/mcp4821.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2023 Anshul Dalal + * + * Driver for Microchip MCP4801, MCP4802, MCP4811, MCP4812, MCP4821 and MCP4822 + * + * Based on the work of: + * Michael Welling (MCP4922 Driver) + * + * Datasheet: + * MCP48x1: https://ww1.microchip.com/downloads/en/DeviceDoc/22244B.pdf + * MCP48x2: https://ww1.microchip.com/downloads/en/DeviceDoc/20002249B.pdf + * + * TODO: + * - Configurable gain + * - Regulator control + */ + +#include +#include +#include + +#include +#include + +#include + +#define MCP4821_ACTIVE_MODE BIT(12) +#define MCP4802_SECOND_CHAN BIT(15) + +/* DAC uses an internal Voltage reference of 4.096V at a gain of 2x */ +#define MCP4821_2X_GAIN_VREF_MV 4096 + +enum mcp4821_supported_drvice_ids { + ID_MCP4801, + ID_MCP4802, + ID_MCP4811, + ID_MCP4812, + ID_MCP4821, + ID_MCP4822, +}; + +struct mcp4821_state { + struct spi_device *spi; + u16 dac_value[2]; +}; + +struct mcp4821_chip_info { + const char *name; + int num_channels; + const struct iio_chan_spec channels[2]; +}; + +#define MCP4821_CHAN(channel_id, resolution) \ + { \ + .type = IIO_VOLTAGE, .output = 1, .indexed = 1, \ + .channel = (channel_id), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .scan_type = { \ + .realbits = (resolution), \ + .shift = 12 - (resolution), \ + }, \ + } + +static const struct mcp4821_chip_info mcp4821_chip_info_table[6] = { + [ID_MCP4801] = { + .name = "mcp4801", + .num_channels = 1, + .channels = { MCP4821_CHAN(0, 8) } + }, + [ID_MCP4802] = { + .name = "mcp4802", + .num_channels = 2, + .channels = { MCP4821_CHAN(0, 8), + MCP4821_CHAN(1, 8) } + }, + [ID_MCP4811] = { + .name = "mcp4811", + .num_channels = 1, + .channels = { MCP4821_CHAN(0, 10) } + }, + [ID_MCP4812] = { + .name = "mcp4812", + .num_channels = 2, + .channels = { MCP4821_CHAN(0, 10), + MCP4821_CHAN(1, 10) } + }, + [ID_MCP4821] = { + .name = "mcp4821", + .num_channels = 1, + .channels = { MCP4821_CHAN(0, 12) } + }, + [ID_MCP4822] = { + .name = "mcp4822", + .num_channels = 2, + .channels = { MCP4821_CHAN(0, 12), + MCP4821_CHAN(1, 12) } + }, +}; + +static int mcp4821_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct mcp4821_state *state; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + state = iio_priv(indio_dev); + *val = state->dac_value[chan->channel]; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = MCP4821_2X_GAIN_VREF_MV; + *val2 = chan->scan_type.realbits; + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } +} + +static int mcp4821_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct mcp4821_state *state = iio_priv(indio_dev); + u16 write_val; + __be16 write_buffer; + int ret; + + if (val2 != 0) + return -EINVAL; + if (val < 0 || val >= BIT(chan->scan_type.realbits)) + return -EINVAL; + if (mask != IIO_CHAN_INFO_RAW) + return -EINVAL; + + write_val = MCP4821_ACTIVE_MODE | val << chan->scan_type.shift; + if (chan->channel) + write_val |= MCP4802_SECOND_CHAN; + write_buffer = cpu_to_be16(write_val); + ret = spi_write(state->spi, &write_buffer, sizeof(write_buffer)); + if (ret) { + dev_err(&state->spi->dev, "Failed to write to device: %d", ret); + return ret; + } + + state->dac_value[chan->channel] = val; + return 0; +} + +static const struct iio_info mcp4821_info = { + .read_raw = &mcp4821_read_raw, + .write_raw = &mcp4821_write_raw, +}; + +static int mcp4821_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct mcp4821_state *state; + const struct mcp4821_chip_info *info; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*state)); + if (indio_dev == NULL) + return -ENOMEM; + + state = iio_priv(indio_dev); + state->spi = spi; + + info = spi_get_device_match_data(spi); + indio_dev->name = info->name; + indio_dev->info = &mcp4821_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = info->channels; + indio_dev->num_channels = info->num_channels; + return devm_iio_device_register(&spi->dev, indio_dev); +} + +#define MCP4821_COMPATIBLE(of_compatible, id) \ + { \ + .compatible = of_compatible, \ + .data = &mcp4821_chip_info_table[id] \ + } + +static const struct of_device_id mcp4821_of_table[] = { + MCP4821_COMPATIBLE("microchip,mcp4801", ID_MCP4801), + MCP4821_COMPATIBLE("microchip,mcp4802", ID_MCP4802), + MCP4821_COMPATIBLE("microchip,mcp4811", ID_MCP4811), + MCP4821_COMPATIBLE("microchip,mcp4812", ID_MCP4812), + MCP4821_COMPATIBLE("microchip,mcp4821", ID_MCP4821), + MCP4821_COMPATIBLE("microchip,mcp4822", ID_MCP4822), + { /* Sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mcp4821_of_table); + +static const struct spi_device_id mcp4821_id_table[] = { + { "mcp4801", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4801]}, + { "mcp4802", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4802]}, + { "mcp4811", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4811]}, + { "mcp4812", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4812]}, + { "mcp4821", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4821]}, + { "mcp4822", (kernel_ulong_t)&mcp4821_chip_info_table[ID_MCP4822]}, + { /* Sentinel */ } +}; +MODULE_DEVICE_TABLE(spi, mcp4821_id_table); + +static struct spi_driver mcp4821_driver = { + .driver = { + .name = "mcp4821", + .of_match_table = mcp4821_of_table, + }, + .probe = mcp4821_probe, + .id_table = mcp4821_id_table, +}; +module_spi_driver(mcp4821_driver); + +MODULE_AUTHOR("Anshul Dalal "); +MODULE_DESCRIPTION("Microchip MCP4821 DAC Driver"); +MODULE_LICENSE("GPL"); -- 2.43.0