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  1. 26 Jul, 2008 1 commit
    • Grant Likely's avatar
      spi: split up spi_new_device() to allow two stage registration. · dc87c98e
      Grant Likely authored 
      spi_new_device() allocates and registers an spi device all in one swoop.
If the driver needs to add extra data to the spi_device before it is
registered, then this causes problems.  This is needed for OF device
tree support so that the SPI device tree helper can add a pointer to
the device node after the device is allocated, but before the device
is registered.  OF aware SPI devices can then retrieve data out of the
device node to populate a platform data structure.

This patch splits the allocation and registration portions of code out
of spi_new_device() and creates two new functions; spi_alloc_device()
and spi_register_device().  spi_new_device() is modified to use the new
functions for allocation and registration.  None of the existing users
of spi_new_device() should be affected by this change.

Drivers using the new API can forego the use of spi_board_info
structure to describe the device layout and populate data into the
spi_device structure directly.

This change is in preparation for adding an OF device tree parser to
generate spi_devices based on data in the device tree.
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Acked-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
      dc87c98e
  3. 24 Jul, 2008 1 commit
    • Grant Likely's avatar
      spi: make spi_board_info.modalias a char array · 102eb975
      Grant Likely authored 
      Currently, 'modalias' in the spi_device structure is a 'const char *'.
The spi_new_device() function fills in the modalias value from a passed in
spi_board_info data block.  Since it is a pointer copy, the new spi_device
remains dependent on the spi_board_info structure after the new spi_device
is registered (no other fields in spi_device directly depend on the
spi_board_info structure; all of the other data is copied).

This causes a problem when dynamically propulating the list of attached
SPI devices.  For example, in arch/powerpc, the list of SPI devices can be
populated from data in the device tree.  With the current code, the device
tree adapter must kmalloc() a new spi_board_info structure for each new
SPI device it finds in the device tree, and there is no simple mechanism
in place for keeping track of these allocations.

This patch changes modalias from a 'const char *' to a fixed char array.
By copying the modalias string instead of referencing it, the dependency
on the spi_board_info structure is eliminated and an outside caller does
not need to maintain a separate spi_board_info allocation for each device.

If searched through the code to the best of my ability for any references
to modalias which may be affected by this change and haven't found
anything.  It has been tested with the lite5200b platform in arch/powerpc.

[dbrownell@users.sourceforge.net: cope with linux-next changes: KOBJ_NAME_LEN obliterated, etc]
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      102eb975
  5. 22 Jul, 2008 1 commit
  7. 06 Feb, 2008 2 commits
  9. 25 Jan, 2008 1 commit
  11. 05 Dec, 2007 2 commits
  13. 15 Nov, 2007 1 commit
  15. 16 Oct, 2007 1 commit
  17. 12 Oct, 2007 1 commit
    • Kay Sievers's avatar
      Driver core: change add_uevent_var to use a struct · 7eff2e7a
      Kay Sievers authored 
      This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: default avatarKay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      7eff2e7a
  19. 31 Jul, 2007 1 commit
    • David Brownell's avatar
      spi device setup gets better error checking · 082c8cb4
      David Brownell authored 
      This updates some error reporting paths in SPI device setup:

 - Move validation logic for SPI chipselects to spi_new_device(),
   which is where it should always have been.

 - In spi_new_device(), emit error messages if the device can't
   be created.  This is LOTS better than a silent failure; though
   eventually, the calling convention should probably change to
   use the <linux/err.h> conventions.

 - Includes one previously-missing check:  SPI masters must always
   have at least one chipselect, even for dedicated busses which
   always keep it selected!

It also adds a FIXME (IDR for dynamic ID allocation) so the issue doesn't live
purely in my mailbox.
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      082c8cb4
  21. 22 Jul, 2007 1 commit
  23. 17 Jul, 2007 1 commit
  25. 04 Jun, 2007 1 commit
  27. 08 May, 2007 1 commit
  29. 27 Mar, 2007 1 commit
  31. 12 Feb, 2007 1 commit
  33. 08 Feb, 2007 1 commit
  35. 07 Feb, 2007 1 commit
  37. 26 Jan, 2007 1 commit
    • Atsushi Nemoto's avatar
      [PATCH] SPI: alternative fix for spi_busnum_to_master · 1e9a51dc
      Atsushi Nemoto authored 
      If a SPI master device exists, udev (udevtrigger) causes kernel crash, due
to wrong kobj pointer in kobject_uevent_env().  This problem was not in
2.6.19.

The backtrace (on MIPS) was:
[<8024db6c>] kobject_uevent_env+0x54c/0x5e8
[<802a8264>] store_uevent+0x1c/0x3c  (in drivers/class.c)
[<801cb14c>] subsys_attr_store+0x2c/0x50
[<801cb80c>] flush_write_buffer+0x38/0x5c
[<801cb900>] sysfs_write_file+0xd0/0x190
[<80181444>] vfs_write+0xc4/0x1a0
[<80181cdc>] sys_write+0x54/0xa0
[<8010dae4>] stack_done+0x20/0x3c

flush_write_buffer() passes kobject of spi_master_class.subsys to
subsys_addr_store(), then subsys_addr_store() passes a pointer to a struct
subsystem to store_uevent() which expects a pointer to a struct
class_device.  The problem seems subsys_attr_store() called instead of
class_device_attr_store().

This mismatch was caused by commit
3bd0f694, which overrides kset of master
class.  This made spi_master_class.subsys.kset.ktype NULL so
subsys_sysfs_ops is used instead of class_dev_sysfs_ops.

The commit was to fix spi_busnum_to_master().  Here is a patch fixes
this function in other way, just searching children list of
class_device.
Signed-off-by: default avatarAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1e9a51dc
  39. 07 Dec, 2006 4 commits
  41. 03 Nov, 2006 1 commit
  43. 03 Jul, 2006 1 commit
  45. 28 Jun, 2006 1 commit
  47. 21 May, 2006 1 commit
  49. 16 May, 2006 2 commits
  51. 21 Feb, 2006 1 commit
  53. 14 Jan, 2006 5 commits
    • Andrew Morton's avatar
      [PATCH] spi: remove fastcall crap · 5d870c8e
      Andrew Morton authored 
      gcc4 generates warnings when a non-FASTCALL function pointer is assigned to a
FASTCALL one.  Perhaps it has taste.

Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      5d870c8e
    • Vitaly Wool's avatar
      [PATCH] spi: use linked lists rather than an array · 8275c642
      Vitaly Wool authored 
      This makes the SPI core and its users access transfers in the SPI message
structure as linked list not as an array, as discussed on LKML.

From: David Brownell <dbrownell@users.sourceforge.net>

  Updates including doc, bugfixes to the list code, add
  spi_message_add_tail().  Plus, initialize things _before_ grabbing the
  locks in some cases (in case it grows more expensive).  This also merges
  some bitbang updates of mine that didn't yet make it into the mm tree.
Signed-off-by: default avatarVitaly Wool <vwool@ru.mvista.com>
Signed-off-by: default avatarDmitry Pervushin <dpervushin@gmail.com>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      8275c642
    • David Brownell's avatar
      [PATCH] SPI core tweaks, bugfix · 0c868461
      David Brownell authored 
      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: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      0c868461
    • David Brownell's avatar
      [PATCH] spi: add spi_driver to SPI framework · b885244e
      David Brownell authored 
      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: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      b885244e
    • David Brownell's avatar
      [PATCH] spi: simple SPI framework · 8ae12a0d
      David Brownell authored 
      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: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      8ae12a0d
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