From mboxrd@z Thu Jan 1 00:00:00 1970 From: wsa@the-dreams.de (Wolfram Sang) Date: Tue, 3 Apr 2018 17:39:25 +0200 Subject: [PATCH v2 5/6] i2c: i2c-stm32f7: Add DMA support In-Reply-To: <1521650940-11651-6-git-send-email-pierre-yves.mordret@st.com> References: <1521650940-11651-1-git-send-email-pierre-yves.mordret@st.com> <1521650940-11651-6-git-send-email-pierre-yves.mordret@st.com> Message-ID: <20180403153925.lg37rezuvs6hefks@ninjato> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > +#define STM32F7_I2C_DMA_LEN_MIN 0x1 ... > + if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) { Are you using DMA for every message with a length >= 1? The setup of that might be more expensive than the DMA gain, if so. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 833 bytes Desc: not available URL: