From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 F016F18991E for ; Wed, 20 Aug 2025 09:05:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755680750; cv=none; b=BPAVWDZFzt+BebfU4sF6SPBgcNFkcfW1TSQxEwVeuDrdHONFS7lWTzwcnq17yXDtsa8+csOu4rSv95o74XAvCCu+ONI2hbOXjCqOGt03YB6YhA/GHmxfQXrxqjJCJc33Bo93gn65Y6T2fsz2plUgrZJh7rnJ38uoZ04RDawKt1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755680750; c=relaxed/simple; bh=rBIWWgSgC3Z1+DJZd9LaEuOIL1k/8mC91rTAmBS9Y0I=; h=Subject:To:From:Date:Message-ID:MIME-Version:Content-Type; b=axQks0JYCxxutUnNG1RS2bUZOayZ4askJfRkXSt8Avdu5jc8Gnyf8SnDKNrZzLk+QJrC9zHXmxzflJqcUN0BNtU6zEyhN8BevHzTtdbXY5LrPl4o+yDT5zPrpEp9+GkAF4rE0xEFCGwqL5JQxZ0EzuP/6S9roJAJW+NVUoTJl8k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B66LJuGH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="B66LJuGH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2ABE5C4CEEB; Wed, 20 Aug 2025 09:05:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755680749; bh=rBIWWgSgC3Z1+DJZd9LaEuOIL1k/8mC91rTAmBS9Y0I=; h=Subject:To:From:Date:From; b=B66LJuGHgt0oI8KmfkdtEW6+GLoPyiS7+wX3vMf/YBmPSssRqx/K/uvN7cHYuu7uR bSspLFIYeJHNevRA5DD1MJg5zxYFYBGDzW2QNWS/UfHJ4dlRNnoK8Jvg84QoUCg88B gHW1x25l1ksRG3o3CPx6OXkwBi/kQaEE2pUKjR34= Subject: patch "iio: temperature: maxim_thermocouple: use DMA-safe buffer for" added to char-misc-linus To: dlechner@baylibre.com,Jonathan.Cameron@huawei.com,Stable@vger.kernel.org,nuno.sa@analog.com From: Date: Wed, 20 Aug 2025 11:05:34 +0200 Message-ID: <2025082034-zesty-matchless-b6aa@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is a note to let you know that I've just added the patch titled iio: temperature: maxim_thermocouple: use DMA-safe buffer for to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From ae5bc07ec9f73a41734270ef3f800c5c8a7e0ad3 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Mon, 21 Jul 2025 18:04:04 -0500 Subject: iio: temperature: maxim_thermocouple: use DMA-safe buffer for spi_read() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Replace using stack-allocated buffers with a DMA-safe buffer for use with spi_read(). This allows the driver to be safely used with DMA-enabled SPI controllers. The buffer array is also converted to a struct with a union to make the usage of the memory in the buffer more clear and ensure proper alignment. Fixes: 1f25ca11d84a ("iio: temperature: add support for Maxim thermocouple chips") Signed-off-by: David Lechner Reviewed-by: Nuno Sá Link: https://patch.msgid.link/20250721-iio-use-more-iio_declare_buffer_with_ts-3-v2-1-0c68d41ccf6c@baylibre.com Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/temperature/maxim_thermocouple.c | 26 ++++++++++++-------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/iio/temperature/maxim_thermocouple.c b/drivers/iio/temperature/maxim_thermocouple.c index cae8e84821d7..205939680fd4 100644 --- a/drivers/iio/temperature/maxim_thermocouple.c +++ b/drivers/iio/temperature/maxim_thermocouple.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -121,8 +122,15 @@ struct maxim_thermocouple_data { struct spi_device *spi; const struct maxim_thermocouple_chip *chip; char tc_type; - - u8 buffer[16] __aligned(IIO_DMA_MINALIGN); + /* Buffer for reading up to 2 hardware channels. */ + struct { + union { + __be16 raw16; + __be32 raw32; + __be16 raw[2]; + }; + aligned_s64 timestamp; + } buffer __aligned(IIO_DMA_MINALIGN); }; static int maxim_thermocouple_read(struct maxim_thermocouple_data *data, @@ -130,18 +138,16 @@ static int maxim_thermocouple_read(struct maxim_thermocouple_data *data, { unsigned int storage_bytes = data->chip->read_size; unsigned int shift = chan->scan_type.shift + (chan->address * 8); - __be16 buf16; - __be32 buf32; int ret; switch (storage_bytes) { case 2: - ret = spi_read(data->spi, (void *)&buf16, storage_bytes); - *val = be16_to_cpu(buf16); + ret = spi_read(data->spi, &data->buffer.raw16, storage_bytes); + *val = be16_to_cpu(data->buffer.raw16); break; case 4: - ret = spi_read(data->spi, (void *)&buf32, storage_bytes); - *val = be32_to_cpu(buf32); + ret = spi_read(data->spi, &data->buffer.raw32, storage_bytes); + *val = be32_to_cpu(data->buffer.raw32); break; default: ret = -EINVAL; @@ -166,9 +172,9 @@ static irqreturn_t maxim_thermocouple_trigger_handler(int irq, void *private) struct maxim_thermocouple_data *data = iio_priv(indio_dev); int ret; - ret = spi_read(data->spi, data->buffer, data->chip->read_size); + ret = spi_read(data->spi, data->buffer.raw, data->chip->read_size); if (!ret) { - iio_push_to_buffers_with_ts(indio_dev, data->buffer, + iio_push_to_buffers_with_ts(indio_dev, &data->buffer, sizeof(data->buffer), iio_get_time_ns(indio_dev)); } -- 2.50.1