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* arm/pxa2xx: reorgazine SSP and SPI header filesSebastian Andrzej Siewior2010-12-011-2/+2
| | | | | | | | | | | | | | | | The PXA-SPI driver relies on some files / defines which are arm specific and are within the ARM tree. The CE4100 SoC which is x86 has also the SPI core. This patch moves the ssp and spi files from arm/mach-pxa and plat-pxa to include/linux where the CE4100 can access them. This move got verified by building the following defconfigs: cm_x2xx_defconfig corgi_defconfig em_x270_defconfig ezx_defconfig imote2_defconfig pxa3xx_defconfig spitz_defconfig zeus_defconfig raumfeld_defconfig magician_defconfig Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
* spi/ep93xx: implemented driver for Cirrus EP93xx SPI controllerMika Westerberg2010-05-251-0/+95
| | | | | | | | | | This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found in EP93xx chips. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* Documentation/spi/* compile warning fixPrarit Bhargava2010-05-251-2/+2
| | | | | | | | | | | | | Fix this warning: Documentation/spi/spidev_fdx.c: In function `do_msg': Documentation/spi/spidev_fdx.c:61: warning: cast from pointer to integer of different size Documentation/spi/spidev_fdx.c:64: warning: cast from pointer to integer of different size buf should be unsigned long to match native arch on 32-bit x86 compile. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* spi: spidev_test gives error upon 1-byte transferHector Palacios2010-04-291-1/+1
| | | | | | | | | | | | | The sample application spidev_test.c is using SPI_IOC_MESSAGE ioctl to do an SPI transfer. This ioctl returns the number of bytes successfully transmitted or a negative error code upon erroneous completion. The application however is returning an error if the result of the ioclt if the return value is 1. This makes the application to fail upon 1-byte length transfers. Signed-off-by: Hector Palacios <hector.palacios@digi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* tree-wide: fix assorted typos all over the placeAndré Goddard Rosa2009-12-041-1/+1
| | | | | | | | | | That is "success", "unknown", "through", "performance", "[re|un]mapping" , "access", "default", "reasonable", "[con]currently", "temperature" , "channel", "[un]used", "application", "example","hierarchy", "therefore" , "[over|under]flow", "contiguous", "threshold", "enough" and others. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* spi: fix spelling of `automatically' in documentationBen Dooks2009-09-231-1/+1
| | | | | | | | | Fix spelling of `automatically' in Documentation/spi/spi-summary. Signed-off-by: Ben Dooks <ben@simtec.co.uk> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGSLadinu Chandrasinghe2009-09-231-2/+2
| | | | | | | | | | | Fix up -Wmissing-prototypes in compileable userspace code, mainly under Documentation/. Signed-off-by: Ladinu Chandrasinghe <ladinu.pub@gmail.com> Signed-off-by: Trevor Keith <tsrk@tsrk.net> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spi: new spi->mode bitsDavid Brownell2009-06-301-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add two new spi_device.mode bits to accomodate more protocol options, and pass them through to usermode drivers: * SPI_NO_CS ... a second 3-wire variant, where the chipselect line is removed instead of a data line; transfers are still full duplex. This obviously has STRONG protocol implications since the chipselect transitions can't be used to synchronize state transitions with the SPI master. * SPI_READY ... defines open drain signal that's pulled low to pause the clock. This defines a 5-wire variant (normal 4-wire SPI plus READY) and two 4-wire variants (READY plus each of the 3-wire flavors). Such hardware flow control can be a big win. There are ADC converters and flash chips that expose READY signals, but not many host controllers support it today. The spi_bitbang code should be changed to use SPI_NO_CS instead of its current nonportable hack. That's a mode most hardware can easily support (unlike SPI_READY). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: "Paulraj, Sandeep" <s-paulraj@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spi: documentation: emphasise spi_master.setup() semanticsDavid Brownell2009-04-211-0/+6
| | | | | | | | | | | | | | | | | This is a doc-only patch which I hope will reduce the number of spi_master controller driver patches starting out with a common implementation bug. (As in: almost every spi_master driver I see starts out with its version of this bug. Sigh.) It just re-emphasizes that the setup() method may be called for one device while a transfer is active on another ... which means that most driver implementations shouldn't touch any registers. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* hwmon: (lm70) Code streamlining and cleanupKaiwan N Billimoria2009-01-071-0/+10
| | | | | | | | | | | | | | This fixes a byteswap bug in the LM70 temperature sensor driver, which was previously covered up by a converse bug in the driver for the LM70EVAL-LLP board (which is also fixed). Other fixes: doc updates, remove an annoying msleep(), and improve three-wire protocol handling. Signed-off-by: Kaiwan N Billimoria <kaiwan@designergraphix.com> [ dbrownell@users.sourceforge.net: doc and whitespace tweaks ] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* spi documentation: use __initdata on structroel kluin2008-12-011-1/+1
| | | | | | | | | Use __initdata for data, not __init. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* .gitignore updatesAlexey Dobriyan2008-10-301-0/+2
| | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pxa2xx_spi: fix chip_info defaults and documentation.Vernon Sauder2008-10-161-11/+23
| | | | | | | | | | | | | | | Make the chip info structure data optional by providing reasonable defaults. Improve corresponding documentation, and highlight the drawback of not providing explicit chipselect control. DMA can determine appropriate dma_burst_size and thresholds automatically so use DMA even if dma_burst_size is not specified. Signed-off-by: Vernon Sauder <VernonInHand@gmail.com> Reviewed-by: Ned Forrester <nforrester@whoi.edu> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* docsrc: build Documentation/ sourcesRandy Dunlap2008-08-121-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | Currently source files in the Documentation/ sub-dir can easily bit-rot since they are not generally buildable, either because they are hidden in text files or because there are no Makefile rules for them. This needs to be fixed so that the source files remain usable and good examples of code instead of bad examples. Add the ability to build source files that are in the Documentation/ dir. Add to Kconfig as "BUILD_DOCSRC" config symbol. Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the Documentation/ sources. Or enable BUILD_DOCSRC in the *config system. However, this symbol depends on HEADERS_CHECK since the header files need to be installed (for userspace builds). Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32, sparc64, powerpc, sh, m68k, & mips. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King2008-08-072-4/+4
| | | | | | This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* documentation: move spidev_fdx example to its own source fileRandy Dunlap2008-04-282-166/+160
| | | | | | | | | | | | Move sample source code to its own source file so that it can be used easier and build-tested/check/maintained by anyone. (Makefile changes are in a separate patch for all of Documentation/.) Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spi: documentation tweaksDavid Brownell2008-04-081-1/+14
| | | | | | | | | | Update SPI documentation to clarify some areas of recent confusion: clock polarity takes effect when chipselect goes active; and zero length buffers are OK in certain cases. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Convert files to UTF-8 and some cleanupsJan Engelhardt2007-10-191-1/+1
| | | | | | | | | | | | | | | | | | * Convert files to UTF-8. * Also correct some people's names (one example is Eißfeldt, which was found in a source file. Given that the author used an ß at all in a source file indicates that the real name has in fact a 'ß' and not an 'ss', which is commonly used as a substitute for 'ß' when limited to 7bit.) * Correct town names (Goettingen -> Göttingen) * Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313) Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Adrian Bunk <bunk@kernel.org>
* spi doesn't need class_deviceTony Jones2007-10-161-8/+17
| | | | | | | | | | | | Make the SPI framework and drivers stop using class_device. Update docs accordingly ... highlighting just which sysfs paths should be "safe"/stable. Signed-off-by: Tony Jones <tonyj@suse.de> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/spi/spidev_test.c: constify some variablesWANG Cong2007-10-161-3/+3
| | | | | | | | | | Constify two char pointers and a struct in Documentation/spi/spidev_test.c. Acked-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spidev_test utilityAnton Vorontsov2007-07-311-0/+202
| | | | | | | | | | | | This is a simple utility used to test SPI functionality. It could stand growing options to support using other test data patterns; this initial version only issues full duplex transfers, which rules out 3WIRE or Microwire links. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spi_lm70llp parport adapter driverKaiwan N Billimoria2007-07-171-0/+69
| | | | | | | | | | | | | | This adds a driver for the LM70-LLP parport adapter, which is an eval board for the LM70 temperature sensor. For those without that board, it may be a simpler example of a parport-to-SPI adapter then spi_butterfly. Signed-off-by: Kaiwan N Billimoria <kaiwan@designergraphix.com> Doc, coding style, and interface updates; build fixes. Minor rename. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* spi doc update: describe clock mode bitsDavid Brownell2007-05-231-5/+48
| | | | | | | | | Update the SPI documentation to cover a few points that have proven to be confusing or unclear; most notably the two clock mode bits. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SPI kerneldocDavid Brownell2007-05-081-19/+24
| | | | | | | | | | | | | | Various documentation updates for the SPI infrastructure, to clarify things that may not have been clear, to cope with lack of editing, and fix omissions. Also, plug SPI into the kernel-api DocBook template, and fix all the resulting glitches in document generation. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* /dev/spidevB.C interfaceAndrea Paterniani2007-05-081-0/+307
| | | | | | | | | | | | | | | | | | | | | | | | Add a filesystem API for <linux/spi/spi.h> stack. The initial version of this interface is purely synchronous. dbrownell@users.sourceforge.net: Cleaned up, bugfixed; much simplified; added preliminary documentation. Works with mdev given CONFIG_SYSFS_DEPRECATED; and presumably udev. Updated SPI_IOC_MESSAGE ioctl to full spi_message semantics, supporting groups of one or more transfers (each of which may be full duplex if desired). This is marked as EXPERIMENTAL with an explicit disclaimer that the API (notably the ioctls) is subject to change. Signed-off-by: Andrea Paterniani <a.paterniani@swapp-eng.it> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [ARM] 4304/1: removes the unnecessary bit number from CKENnn_XXXXEric Miao2007-04-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes the unnecessary bit number from CKENnn_XXXX definitions for PXA, so that CKEN0_PWM0 --> CKEN_PWM0 CKEN1_PWM1 --> CKEN_PWM1 ... CKEN24_CAMERA --> CKEN_CAMERA The reasons for the change of these defitions are: 1. they do not scale - they are currently valid for pxa2xx, but definitely not valid for pxa3xx, e.g., pxa3xx has bit 3 for camera instead of bit 24 2. they are unnecessary - the peripheral name within the definition has already announced its usage, we don't need those bit numbers to know which peripheral we are going to enable/disable clock for 3. they are inconvenient - think about this: a driver programmer for pxa has to remember which bit in the CKEN register to turn on/off Another change in the patch is to make the definitions equal to its clock bit index, so that #define CKEN_CAMERA (24) instead of #define CKEN_CAMERA (1 << 24) this change, however, will add a run-time bit shift operation in pxa_set_cken(), but the benefit of this change is that it scales when bit index exceeds 32, e.g., pxa3xx has two registers CKENA and CKENB, totally 64 bit for this, suppose CAMERA clock enabling bit is CKENB:10, one can simply define CKEN_CAMERA to be (32 + 10) and so that pxa_set_cken() need minimum change to adapt to that. Signed-off-by: eric miao <eric.y.miao@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] spi: documentation does not need to set driver's bus_type fieldBen Dooks2007-02-121-1/+0
| | | | | | | | | | The spi_register_driver() sets the bus_type field of the spi_driver being registered, so there is no need to have it set in the driver itself. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] spi: add spi_set_drvdata() and spi_get_drvdata()Ben Dooks2007-02-121-1/+1
| | | | | | | | | | | Add wrappers for getting and setting the driver data using spi_device instead of using dev_{get|set}_drvdata with &spi->dev, to mirror the platform_{get|set}_drvdata. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] spi: stabilize PIO mode transfers on PXA2xx systemsStephen Street2006-12-101-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stabilize PIO mode transfers against a range of word sizes and FIFO thresholds and fixes word size setup/override issues. 1) 16 and 32 bit DMA/PIO transfers broken due to timing differences. 2) Potential for bad transfer counts due to transfer size assumptions. 3) Setup function broken is multiple ways. 4) Per transfer bit_per_word changes break DMA setup in pump_tranfers. 5) False positive timeout are not errors. 6) Changes in pxa2xx_spi_chip not effective in calls to setup. 7) Timeout scaling wrong for PXA255 NSSP. 8) Driver leaks memory while busy during unloading. Known issues: SPI_CS_HIGH and SPI_LSB_FIRST settings in struct spi_device are not handled. Testing: This patch has been test against the "random length, random bits/word, random data (verified on loopback) and stepped baud rate by octaves (3.6MHz to 115kHz)" test. It is robust in PIO mode, using any combination of tx and rx thresholds, and also in DMA mode (which internally computes the thresholds). Much thanks to Ned Forrester for exhaustive reviews, fixes and testing. The driver is substantially better for his efforts. Signed-off-by: Stephen Street <stephen@streetfiresound.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Documentation: remove duplicated wordsPaolo Ornati2006-10-032-5/+5
| | | | | | | | | | | | | | | Remove many duplicated words under Documentation/ and do other small cleanups. Examples: "and and" --> "and" "in in" --> "in" "the the" --> "the" "the the" --> "to the" ... Signed-off-by: Paolo Ornati <ornati@fastwebnet.it> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] SPI: busnum == 0 needs to workDavid Brownell2006-05-161-1/+33
| | | | | | | | | | | | | We need to be able to have a "SPI bus 0" matching chip numbering; but that number was wrongly used to flag dynamic allocation of a bus number. This patch resolves that issue; now negative numbers trigger dynamic alloc. It also updates the how-to-write-a-controller-driver overview to mention this stuff. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] SPI: add PXA2xx SSP SPI DriverStephen Street2006-05-161-0/+234
| | | | | | | | | | | | | | | | | This driver turns a PXA2xx synchronous serial port (SSP) into a SPI master controller (see Documentation/spi/spi_summary). The driver has the following features: - Support for any PXA2xx SSP - SSP PIO and SSP DMA data transfers. - External and Internal (SSPFRM) chip selects. - Per slave device (chip) configuration. - Full suspend, freeze, resume support. Signed-off-by: Stephen Street <stephen@streetfiresound.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] SPI: spi_butterfly, restore lost deltasDavid Brownell2006-02-061-6/+17
| | | | | | | | | | This resolves some minor version skew glitches that accumulated for the AVR Butterfly adapter driver, which caused among other things the existence of a duplicate Kconfig entry. Most of it boils down to comment updates, but in one case it removes some now-superfluous code that would be better if not copied into other controller-level drivers. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
* [PATCH] SPI: add spi_butterfly driverDavid Brownell2006-01-131-0/+57
| | | | | | | | This adds a bitbanging parport based adaptor cable for AVR Butterfly, giving SPI links to its DataFlash chip and (eventually) firmware running in the card. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] spi: misc fixesDavid Brownell2006-01-131-0/+13
| | | | | | | | | | | | | This collects some small SPI patches that seem to be missing from the MM tree: - spi_butterfly kbuild hooks got dropped somehow; this restores them - quick fix for a (theoretical?) m25p80_write() oops noted by Andrew - quick fix for a potential config-specific oops for mtd_dataflash() - minor doc tweaks Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] SPI core tweaks, bugfixDavid Brownell2006-01-131-0/+16
| | | | | | | | | | | | | | | | | | | | | | | This includes various updates to the SPI core: - Fixes a driver model refcount bug in spi_unregister_master() paths. - The spi_master structures now have wrappers which help keep drivers from needing class-level get/put for device data or for refcounts. - Check for a few setup errors that would cause oopsing later. - Docs say more about memory management. Highlights the use of DMA-safe i/o buffers, and zero-initializing spi_message and such metadata. - Provide a simple alloc/free for spi_message and its spi_transfer; this is only one of the possible memory management policies. Nothing to break code that already works. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] spi: add spi_driver to SPI frameworkDavid Brownell2006-01-131-20/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a refresh of the "Simple SPI Framework" found in 2.6.15-rc3-mm1 which makes the following changes: * There's now a "struct spi_driver". This increase the footprint of the core a bit, since it now includes code to do what the driver core was previously handling directly. Documentation and comments were updated to match. * spi_alloc_master() now does class_device_initialize(), so it can at least be refcounted before spi_register_master(). To match, spi_register_master() switched over to class_device_add(). * States explicitly that after transfer errors, spi_devices will be deselected. We want fault recovery procedures to work the same for all controller drivers. * Minor tweaks: controller_data no longer points to readonly data; prevent some potential cast-from-null bugs with container_of calls; clarifies some existing kerneldoc, And a few small cleanups. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] spi: simple SPI frameworkDavid Brownell2006-01-131-0/+416
This is the core of a small SPI framework, implementing the model of a queue of messages which complete asynchronously (with thin synchronous wrappers on top). - It's still less than 2KB of ".text" (ARM). If there's got to be a mid-layer for something so simple, that's the right size budget. :) - The guts use board-specific SPI device tables to build the driver model tree. (Hardware probing is rarely an option.) - This version of Kconfig includes no drivers. At this writing there are two known master controller drivers (PXA/SSP, OMAP MicroWire) and three protocol drivers (CS8415a, ADS7846, DataFlash) with LKML mentions of other drivers in development. - No userspace API. There are several implementations to compare. Implement them like any other driver, and bind them with sysfs. The changes from last version posted to LKML (on 11-Nov-2005) are minor, and include: - One bugfix (removes a FIXME), with the visible effect of making device names be "spiB.C" where B is the bus number and C is the chipselect. - The "caller provides DMA mappings" mechanism now has kerneldoc, for DMA drivers that want to be fancy. - Hey, the framework init can be subsys_init. Even though board init logic fires earlier, at arch_init ... since the framework init is for driver support, and the board init support uses static init. - Various additional spec/doc clarifications based on discussions with other folk. It adds a brief "thank you" at the end, for folk who've helped nudge this framework into existence. As I've said before, I think that "protocol tweaking" is the main support that this driver framework will need to evolve. From: Mark Underwood <basicmark@yahoo.com> Update the SPI framework to remove a potential priority inversion case by reverting to kmalloc if the pre-allocated DMA-safe buffer isn't available. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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