Add a new spi_master.flags word listing constraints relevant to that
controller. Define the first constraint bit: a half duplex restriction.
Include that constraint in the OMAP1 MicroWire controller driver.
Have the mmc_spi host be the first customer of this flag. Its coding
relies heavily on full duplex transfers, so it must fail when the
underlying controller driver won't perform them.
(The spi_write_then_read routine could use it too: use the
temporarily-withdrawn full-duplex speedup unless this flag is set, in
which case the existing code applies. Similarly, any spi_master
implementing only SPI_3WIRE should set the flag.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch changes the reported error code for the responses
to a command from EINVAL to EFAULT/ENOSYS, as EINVAL is reserved
for non-recoverable host errors, and the responses from
the SD/MMC card may be because of recoverable transmission
errors in the command or in the response. Response codes
in SPI mode are NOT protected by a checksum, so don't trust them.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Acked-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
Speedup for slow cards by transfering more data at once.
This patch also reduces the amount of wear-out of the flash
blocks because fewer partial blocks are written.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
A very large subset of SD cards in the market send their
responses and data non-byte-aligned. So add logic to the
mmc spi driver to handle this mess.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
SD/MMC card timeouts can be very high. So avoid busy-waiting,
using the scheduler. Calculate all timeouts in jiffies units,
because this will give us the correct sign when to involve
the scheduler.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
Some cards are not able to send the data token in time, but
miss the time frame for some bits(!). So synchronize to the
start of the token.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some cards are slower than the standard allows and need more
time to respond to a command. Max. observed number of bytes
was 12.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Allow the platform data structures to specify spi mode 3
(if there is a pullup on the clock line or the spi hardware
is not able to serve spi mode 0).
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The support is implemented via platform data accessors, new module
(of_mmc_spi) will be created automatically when the driver compiles
on OpenFirmware platforms. Link-time dependency will load the module
automatically.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Hard-coded timeout values of 250ms for writes and 100ms for reads are
currently used for MMC transactions over SPI. The spec states that the
timeout values from the card should be used.
Signed-off-by: Matthew Fleming <matthew.fleming@imgtec.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The original intention was to write a zero byte to mmc to force spi
signals to low when doing power off. Somehow the spi_w8r8 call got there
so a read followed the write of single zero byte. This patch changes
that to simple write of zero byte without the following read.
This way the power off is more reliable and completely sufficient.
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Relax requirements on host controllers and only require that they do not
report a transfer count than is larger than the actual one (i.e. a lower
value is okay). This is how many other parts of the kernel behaves so
upper layers should already be prepared to handle that scenario. This
gives us a performance boost on MMC cards.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Now get_ro() callback must return 0/1 values for its logical states, and
negative errno values in case of error. If particular host instance doesn't
support RO/WP switch, it should return -ENOSYS.
This patch changes some hosts in two ways:
1. Now functions should be smart to not return negative values in
"RO asserted" case (particularly gpio_ calls could return negative
values for the outermost GPIOs).
Also, board code usually passes get_ro() callbacks that directly return
gpioreg & bit result, so at91_mci, imxmmc, pxamci and mmc_spi's get_ro()
handlers need take special care when returning platform's values to the
mmc core.
2. In case of host instance didn't implement get_ro() callback, it should
really return -ENOSYS and let the mmc core decide what to do about it
(mmc core thinks the same way as the hosts, so it isn't functional
change).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch adds new platform data variable "caps", so platforms
could pass theirs capabilities into MMC core (for example, platforms
without interrupt on the CD line will most probably want to pass
MMC_CAP_NEEDS_POLL).
New platform get_cd() callback provided to optimize polling.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Tony Jones <tonyj@suse.de>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given the patch which simplifies the spi_sync calling convention, this one
updates the callers of that routine which tried using it according to the
previous specification. (Most didn't.)
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
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 49dce689ad changed the sysfs data
structures for SPI in a way which broke the MMC-over-SPI host driver.
This patch fixes that regression by changing the scheme used to keep
from knowingly trying to use a shared bus segment, and updates the
adjacent comments slightly to better explain the issue.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
AFAICS, fallout from repacing include of blkdev.h with include of bio.h.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Make sure the mmc_spi driver can build without CONFIG_BLOCK.
Issue noted by "Avuton Olrich" <avuton@gmail.com> and randconfig.
While that won't be a common configuration, sometimes embedded
boards use SDIO to interface WLAN or Bluetooth chips (vs some
parallel interface), and don't provide an MMC/SD socket for use
with flash memory cards.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the latest version of the MMC-over-SPI support. It works
on 2.6.23-rc2 plus git-mmc (from rc1-mm2), along with the preceding
patches which teach the rest of the MMC stack about SPI.
The main issue of note is that sometimes cards need to be power cycled
to recover after certain faults. Also, it may sometimes be necessary
to disable CRCs. ("modprobe mmc_core use_spi_crc=n")
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: mikael.starvik@axis.com,
Cc: Hans-Peter Nilsson <hp@axis.com>
Cc: Jan Nikitenko <jan.nikitenko@gmail.com>
Cc: Mike Lavender <mike@steroidmicros.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
