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Fri, 11 Sep 2026 04:06:57 -0700 (PDT) Received: from fedora ([154.182.82.204]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49e60ac411asm66109065e9.8.2026.09.11.04.06.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 11 Sep 2026 04:06:57 -0700 (PDT) From: Abdelnasser Hussein To: jic23@kernel.org, gregkh@linuxfoundation.org, nuno.sa@analog.com, Michael.Hennerich@analog.com Cc: dlechner@baylibre.com, andy@kernel.org, linux@analog.com, linux-iio@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, joshua.crofts1@gmail.com, Abdelnasser Hussein Subject: [PATCH v5 0/2] staging: iio: adc: ad7816: Fix SPI read race condition and DMA safety Date: Fri, 11 Sep 2026 14:04:54 +0300 Message-ID: <20260911110456.24873-1-abdelnasserhussein11@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series addresses two separate issues in the ad7816 driver: 1. A race condition during SPI reads where multiple threads could disrupt the GPIO state. 2. A DMA safety issue caused by using a stack-allocated buffer for SPI transfers. Changes in v5: - Split the changes into two separate patches for bisectability, as requested by reviewers. - Patch 1 focuses only on serializing the SPI read operations using guard(mutex) and devm_mutex_init(). - Patch 2 focuses only on replacing the stack buffer with a dedicated rx_buf aligned with IIO_DMA_MINALIGN. - Updated commit messages to better describe the architectural issues. Abdelnasser Hussein (2): staging: iio: adc: ad7816: Serialize SPI read operations staging: iio: adc: ad7816: Use DMA-safe buffer for SPI read drivers/staging/iio/adc/ad7816.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) -- 2.54.0