Commit Graph

15 Commits

Author SHA1 Message Date
David Brownell dccd573bb0 SPI controller drivers: check for unsupported modes
Minor SPI controller driver updates: make the setup() methods reject
spi->mode bits they don't support, by masking aginst the inverse of bits
they *do* support.  This insures against misbehavior later when new mode
bits get added.

Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH.
Support for all four SPI clock/transfer modes is routine.

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>
2007-07-17 10:23:04 -07:00
Chris Lesiak a836f5856a [PATCH] spi: destroy workqueue after spi_unregister_master
Fix a bug in the cleanup of an spi_bitbang bus.

The workqueue associated with the bus was destroyed before the call to
spi_unregister_master.  That meant that spi devices on that bus would be
unable to do IO in their remove method.  The shutdown flag should have been
able to prevent a segfault, but was never getting set.  By waiting to
destroy the workqueue until after the master is unregistered, devices are
able to do IO in their remove methods.  An added benefit is that neither
the shutdown flag nor a wait for the queue of messages to empty is needed.

Signed-off-by: Chris Lesiak <chris.lesiak@licor.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>
2007-03-16 19:25:04 -07:00
Hans-Peter Nilsson 0ffa028505 [PATCH] SPI cleanup() method param becomes non-const
I'd like to assign NULL to kfree()d members of a structure.  I can't do
that without ugly casting (see the PXA patch) when the structure pointed to
is const-qualified.  I don't really see a reason why the cleanup method
isn't allowed to alter the object it should clean up.  :-)

No, I didn't test the PXA patch, but I verified that the NULL-assignment
doesn't stop me from doing rmmod/insmodding my own spi_bitbang-based
driver.

Signed-off-by: Hans-Peter Nilsson <hp@axis.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>
2007-02-12 09:48:31 -08:00
Hans-Peter Nilsson 7f8c7619ea [PATCH] spi_bitbang(): use overridable setup_transfer() method
A small bug-fix for spi_bitbang: it must always call the setup_transfer
function via the overridable pointer, not assume that its
spi_bitbang_setup_transfer is sufficient.  Otherwise, if all options in the
transfers are default (0), the overrided function will never be called.

Granted, the function replacing it must call spi_bitbang_setup_transfer,
but it might also have other important things to do, even if the second
argument (the spi_transfer) is NULL.  Tested together with the other
patches on the spi_crisv32_sser and spi_crisv32_gpio drivers (not yet in
the kernel, will IIUC be submitted as part of the usual
arch-maintainer-pushes).

Signed-off-by: Hans-Peter Nilsson <hp@axis.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>
2007-02-12 09:48:31 -08:00
Greg Kroah-Hartman 07b2463046 Revert "Driver core: convert SPI code to use struct device"
This reverts commit 2943ecf2ed.

This should go through the SPI maintainer, it was my fault that it did
not.  Especially as it conflicts with other patches he has pending.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 21:34:08 -08:00
Greg Kroah-Hartman 2943ecf2ed Driver core: convert SPI code to use struct device
Converts from using struct "class_device" to "struct device" making
everything show up properly in /sys/devices/ with symlinks from the
/sys/class directory.

Cc: <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:11 -08:00
Christoph Lameter e94b176609 [PATCH] slab: remove SLAB_KERNEL
SLAB_KERNEL is an alias of GFP_KERNEL.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:24 -08:00
David Howells c4028958b6 WorkStruct: make allyesconfig
Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:57:56 +00:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
David Brownell 1e316d7566 [PATCH] SPI: spi_bitbang: clocking fixes
This fixes two problems triggered by the MMC stack updating clocks:

 - SPI masters driver should accept a max clock speed of zero; that's one
   convention for marking idle devices.  (Presumably that helps controllers
   that don't autogate clocks to "off" when not in use.)

 - There are more than 1000 nanoseconds per millisecond; setting the clock
   down to 125 KHz now works properly.

Showing once again that Zero (http://en.wikipedia.org/wiki/Zero) is still
an inexhaustible number of bugs.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16 14:33:58 -07:00
David Brownell ccf77cc4af [PATCH] SPI: devices can require LSB-first encodings
Add spi_device hook for LSB-first word encoding, and update all the
(in-tree) controller drivers to reject such devices.  Eventually,
some controller drivers will be updated to support lsb-first encodings
on the wire; no current drivers need this.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16 14:33:57 -07:00
Kumar Gala ff9f4771b5 [PATCH] SPI: Renamed bitbang_transfer_setup to spi_bitbang_setup_transfer and export it
Renamed bitbang_transfer_setup to follow convention of other exported symbols
from spi-bitbang.  Exported spi_bitbang_setup_transfer to allow users of
spi-bitbang to use the function in their own setup_transfer.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16 14:33:57 -07:00
Imre Deak 4cff33f94f [PATCH] SPI: per-transfer overrides for wordsize and clocking
Some protocols (like one for some bitmap displays) require different clock
speed or word size settings for each transfer in an SPI message. This adds
those parameters to struct spi_transfer.  They are to be used when they are
nonzero; otherwise the defaults from spi_device are to be used.

The patch also adds a setup_transfer callback to spi_bitbang, uses it for
messages that use those overrides, and implements it so that the pure
bitbanging code can help resolve any questions about how it should work.

Signed-off-by: Imre Deak <imre.deak@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16 14:33:56 -07:00
Vitaly Wool 8275c642cc [PATCH] spi: use linked lists rather than an array
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: Vitaly Wool <vwool@ru.mvista.com>
Signed-off-by: Dmitry Pervushin <dpervushin@gmail.com>
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>
2006-01-13 16:29:56 -08:00
David Brownell 9904f22a72 [PATCH] spi: add spi_bitbang driver
This adds a bitbanging spi master, hooking up to board/adapter-specific glue
code which knows how to set and read the signals (gpios etc).

This code kicks in after the glue code creates a platform_device with the
right platform_data.  That data includes I/O loops, which will usually
come from expanding an inline function (provided in the header).  One goal
is that the I/O loops should be easily optimized down to a few GPIO register
accesses, in common cases, for speed and minimized overhead.

This understands all the currently defined protocol tweaking options in the
SPI framework, and might eventually serve as as reference implementation.

  - different word sizes (1..32 bits)
  - differing clock rates
  - SPI modes differing by CPOL (affecting chip select and I/O loops)
  - SPI modes differing by CPHA (affecting I/O loops)
  - delays (usecs) after transfers
  - temporarily deselecting chips in mid-transfer

A lot of hardware could work with this framework, though common types of
controller can't reach peak performance without switching to a driver
structure that supports pipelining of transfers (e.g.  DMA queues) and maybe
controllers (e.g.  IRQ driven).

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>
2006-01-13 16:29:55 -08:00