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[79.136.29.16]) by smtp.gmail.com with ESMTPSA id e94sm2170532lfi.23.2019.01.26.08.32.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 26 Jan 2019 08:32:23 -0800 (PST) From: Jonas Bonn To: linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Cc: Jonas Bonn Subject: [PATCH v3 0/2] spi: support inter-word delays Date: Sat, 26 Jan 2019 17:32:18 +0100 Message-Id: <20190126163220.26421-1-jonas@norrbonn.se> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changed in v3: * Drop setting of inter-word delay via device tree Changed in v2: * Fix atmel-spi driver to not unconditionally set minimal delay if no delay is required (erroneous clamping) This short series adds support for SPI inter-word delays and configures the spi-atmel driver to honour the setting. Some SPI slaves are so slow that they are unable to keep up even at the SPI controller's lowest available clock frequency. I have such a configuration where an AVR-based SPI slave is unable to feed the SPI bus fast enough even the SPI master runs at the lowest possible clock speed. Jonas Bonn (2): spi: support inter-word delay requirement for devices spi-atmel: support inter-word delay drivers/spi/spi-atmel.c | 18 +++++++++++++----- include/linux/spi/spi.h | 3 +++ 2 files changed, 16 insertions(+), 5 deletions(-) -- 2.19.1