summaryrefslogtreecommitdiffstats
path: root/Documentation/spi/spi-summary
Commit message (Collapse)AuthorAgeFilesLines
* spi: create a message queueing infrastructureLinus Walleij2012-03-071-12/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This rips the message queue in the PL022 driver out and pushes it into (optional) common infrastructure. Drivers that want to use the message pumping thread will need to define the new per-messags transfer methods and leave the deprecated transfer() method as NULL. Most of the design is described in the documentation changes that are included in this patch. Since there is a queue that need to be stopped when the system is suspending/resuming, two new calls are implemented for the device drivers to call in their suspend()/resume() functions: spi_master_suspend() and spi_master_resume(). ChangeLog v1->v2: - Remove Kconfig entry and do not make the queue support optional at all, instead be more agressive and have it as part of the compulsory infrastructure. - If the .transfer() method is implemented, delete print a small deprecation notice and do not start the transfer pump. - Fix a bitrotted comment. ChangeLog v2->v3: - Fix up a problematic sequence courtesy of Chris Blair. - Stop rather than destroy the queue on suspend() courtesy of Chris Blair. Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> 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>
* 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>
* 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>
* [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King2008-08-071-2/+2
| | | | | | This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 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>
* 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>
* 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>
* [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>
* Documentation: remove duplicated wordsPaolo Ornati2006-10-031-2/+2
| | | | | | | | | | | | | | | 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: 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>
OpenPOWER on IntegriCloud