From mboxrd@z Thu Jan 1 00:00:00 1970 From: Balaji Rao Subject: [PATCH 0/2] spi: Add support for non-blocking synchronous transfers Date: Sat, 28 Feb 2009 13:40:36 +0530 Message-ID: <20090228081036.31964.80618.stgit@fedora.yogi> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: spi-devel-general@lists.sourceforge.net, Andy Green , David Brownell To: linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org Hi, During the course of development of an accelerometer driver, we saw the necessity to execute spi transfers synchronously within an interrupt handler. When using a workqueue instead, we observed a huge number of overruns with very high cpu utlization, which is unacceptable. This series adds a new interface for this and modifies no existing ones. [PATCH 1/2] - Adds synchronous non-blocking transfer support to spi core [PATCH 2/2] - Implements this support in spi_bitbang.c Balaji Rao (2): spi_bitbang: Add support for non-blocking synchronous transfers spi: Add support for non-blocking synchronous transfers drivers/spi/spi_bitbang.c | 227 +++++++++++++++++++++------------------ include/linux/spi/spi.h | 31 +++++ include/linux/spi/spi_bitbang.h | 5 + 3 files changed, 156 insertions(+), 107 deletions(-) -- Balaji Rao