From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753128Ab1GPCsc (ORCPT ); Fri, 15 Jul 2011 22:48:32 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:41590 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751179Ab1GPCsb (ORCPT ); Fri, 15 Jul 2011 22:48:31 -0400 Date: Sat, 16 Jul 2011 11:48:22 +0900 From: Mark Brown To: Greg KH , Grant Likely , Jean Delvare , Ben Dooks Cc: Dimitris Papastamos , Liam Girdwood , Samuel Oritz , linux-kernel@vger.kernel.org Subject: [PATCH 0/4] regmap: Generic I2C and SPI register map library Message-ID: <20110716024817.GC17883@opensource.wolfsonmicro.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a version of a series I've been posting for most of this release cycle which abstracts out a bunch of widely duplicated code for doing register I/O on devices with control slow buses like I2C and SPI. As well as saving us code for the register I/O itself this should also make it easier to factor out further higher level code for this class of devices. This version of the series includes a number of fairly small updates from review by Grant and Jean and also a moderately invasive change to have bus-specific registration functions at Grant's request. I realise it's a bit late in the cycle but it'd be really good if we could get this merged in the next merge window, or accepted for about then so we can create a stable branch we can merge into subsystem trees in order to get drivers using this merged for 3.2. As there's only one user included the series it should be pretty low risk. The code is in a subdirectory because I'm anticipating it'll grow quite a bit as we add facilities like fancy cache mechanisms on top of it. A more verbose cover letter: Many I2C and SPI based devices implement register maps on top of the raw wire interface. This is generally done in a very standard fashion by devices, resulting in a lot of very similar code in drivers. For some time now ASoC has factored this code out into the subsystem but that's only useful for audio devices. The intention with this series is to generalise the concept so that it can be used throughout the kernel. It's not intended that this be suitable for all devices - some devices have things that are hard to generalise like registers with variable size and paging which are hard to support genericly. At the minute the code is focused on the common cases. It is likely that the same code could be used with other buses with similar properties to I2C and SPI. Currently only physical I/O is handled, the intention is that once this support has been reviewed and merged the generic register cache code that ASoC includes will also be factored out too, along with logging and diagnostic infrastructure for register maps. For devices with read heavy workloads (especially those that need a lot of read/modify/write cycles) or which don't support read at all this can provide a useful performance improvement and for sparse register maps there's a lot of benefit in relatively complex cache code. I'm not entirely happy with the implementation currently but am fairly happy with the external interfaces. A bunch more drivers have been converted to use this framework, including the existing ASoC register I/O code, but due to various -next dependencies these don't apply easily so I've omitted them from this posting of the series - you can see them in the mailing list archives, they've not been updated during the review. There's a git branch at: git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next I've also created a regmap-asoc branch there which merges current ASoC code with the regmap code. The following changes since commit 620917de59eeb934b9f8cf35cc2d95c1ac8ed0fc: Linux 3.0-rc7 (2011-07-11 16:51:52 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next Mark Brown (4): regmap: Add generic non-memory mapped register access API regmap: Add I2C bus support regmap: Add SPI bus support regulator: Convert tps65023 to use regmap API MAINTAINERS | 9 + drivers/base/Kconfig | 2 + drivers/base/Makefile | 1 + drivers/base/regmap/Kconfig | 6 + drivers/base/regmap/Makefile | 1 + drivers/base/regmap/regmap.c | 455 ++++++++++++++++++++++++++++++++ drivers/i2c/Kconfig | 4 + drivers/i2c/Makefile | 1 + drivers/i2c/i2c-regmap.c | 115 ++++++++ drivers/regulator/Kconfig | 1 + drivers/regulator/tps65023-regulator.c | 97 ++----- drivers/spi/Kconfig | 4 + drivers/spi/Makefile | 1 + drivers/spi/spi-regmap.c | 73 +++++ include/linux/regmap.h | 79 ++++++ 15 files changed, 779 insertions(+), 70 deletions(-) create mode 100644 drivers/base/regmap/Kconfig create mode 100644 drivers/base/regmap/Makefile create mode 100644 drivers/base/regmap/regmap.c create mode 100644 drivers/i2c/i2c-regmap.c create mode 100644 drivers/spi/spi-regmap.c create mode 100644 include/linux/regmap.h