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Mon, 19 May 2025 11:27:16 -0700 (PDT) Received: from localhost.localdomain ([223.181.108.253]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-742a96e20fbsm6525746b3a.35.2025.05.19.11.27.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 May 2025 11:27:16 -0700 (PDT) From: I Viswanath To: linux-i2c@vger.kernel.org Cc: wsa+renesas@sang-engineering.com, I Viswanath Subject: [PATCH v2] i2c: Clarify behavior of I2C_M_RD flag Date: Tue, 20 May 2025 05:26:57 +0530 Message-ID: <20250519235657.7404-1-viswanathiyyappan@gmail.com> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Update the description of I2C_M_RD to clarify that not setting it signals a write transaction Signed-off-by: I Viswanath --- include/uapi/linux/i2c.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h index aa751389de07..29b149ca4b70 100644 --- a/include/uapi/linux/i2c.h +++ b/include/uapi/linux/i2c.h @@ -21,7 +21,8 @@ * * @flags: * Supported by all adapters: - * %I2C_M_RD: read data (from slave to master). Guaranteed to be 0x0001! + * %I2C_M_RD: read data (from slave to master). Guaranteed to be 0x0001! If + * not set, the transaction is interpreted as write. * * Optional: * %I2C_M_DMA_SAFE: the buffer of this message is DMA safe. Makes sense only