linux-stable.git/drivers/spi, branch linux-2.6.26.y

pxa2xx_spi: fix build breakage

2008-10-09T03:22:50+00:00

commit 20b918dc77b383e9779dafceee3f2198a6f7b0e5 upstream

This patch fixes a build error in the pxa2xx-spi driver,
introduced by commit 7e96445533ac3f4f7964646a202ff3620602fab4
("pxa2xx_spi: dma bugfixes")

  CC      drivers/spi/pxa2xx_spi.o
drivers/spi/pxa2xx_spi.c: In function 'map_dma_buffers':
drivers/spi/pxa2xx_spi.c:331: error: invalid operands to binary &
drivers/spi/pxa2xx_spi.c:331: error: invalid operands to binary &
drivers/spi/pxa2xx_spi.c: In function 'pump_transfers':
drivers/spi/pxa2xx_spi.c:897: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'unsigned int'

[dbrownell@users.sourceforge.net: fix warning too ]

Signed-off-by: Mike Rapoport 
Acked-by: Eric Miao 
Signed-off-by: Andrew Morton 
Signed-off-by: David Brownell 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

pxa2xx_spi: chipselect bugfixes

2008-10-09T03:22:50+00:00

commit 8423597d676615f3dd2d9ab36f59f147086b90b8 upstream

Fixes several chipselect bugs in the pxa2xx_spi driver.  These bugs are in
all versions of this driver and prevent using it with chips like m25p16
flash.

 1. The spi_transfer.cs_change flag is handled too early:
    before spi_transfer.delay_usecs applies, thus making the
    delay ineffective at holding chip select.

 2. spi_transfer.delay_usecs is ignored on the last transfer
    of a message (likewise not holding chipselect long enough).

 3. If spi_transfer.cs_change is set on the last transfer, the
    chip select is always disabled, instead of the intended
    meaning: optionally holding chip select enabled for the
    next message.

Those first three bugs were fixed with a relocation of delays
and chip select de-assertions.

 4. If a message has the cs_change flag set on the last transfer,
    and had the chip select stayed enabled as requested (see 3,
    above), it would not have been disabled if the next message is
    for a different chip.  Fixed by dropping chip select regardless
    of cs_change at end of a message, if there is no next message
    or if the next message is for a different chip.

This patch should apply to all kernels back to and including 2.6.20;
it was test patched against 2.6.20.  An additional patch would be
required for older kernels, but those versions are very buggy anyway.

Signed-off-by: Ned Forrester 
Cc: Vernon Sauder 
Cc: Eric Miao 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

pxa2xx_spi: dma bugfixes

2008-10-09T03:22:50+00:00

commit 7e96445533ac3f4f7964646a202ff3620602fab4 upstream

Fixes two DMA bugs in the pxa2xx_spi driver.  The first bug is in all
versions of this driver; the second was introduced in the 2.6.20 kernel,
and prevents using the driver with chips like m25p16 flash (which can
issue large DMA reads).

 1. Zero length transfers are permitted for use to insert timing,
    but pxa2xx_spi.c will fail if this is requested in DMA mode.
    Fixed by using programmed I/O (PIO) mode for such transfers.

 2. Transfers larger than 8191 are not permitted in DMA mode.  A
    test for length rejects all large transfers regardless of DMA
    or PIO mode.  Worked around by rejecting only large transfers
    with DMA mapped buffers, and forcing all other transfers
    larger than 8191 to use PIO mode.  A rate limited warning is
    issued for DMA transfers forced to PIO mode.

This patch should apply to all kernels back to and including 2.6.20;
it was test patched against 2.6.20.  An additional patch would be
required for older kernels, but those versions are very buggy anyway.

Signed-off-by: Ned Forrester 
Cc: Vernon Sauder 
Cc: Eric Miao 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mpc52xx_psc_spi: fix block transfer

2008-08-01T19:43:11+00:00

commit 9a7867e1b34c3575e7e76a05c0c54c6edbdae2a4 upstream

The block transfer routine in the mpc52xx psc spi driver misinterpret
the datasheet.  According to the processor datasheet the chipselect is
held as long as the EOF is not written.

Theoretically blocks of any sizes can be transferred in this way.  The
old routine however writes an EOF after every word, which has the size
of size_of_word.  This makes the transfer slow.

Also fixed some duplicate code.

Signed-off-by: Luotao Fu 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

spi: fix the read path in spidev

2008-07-04T17:40:08+00:00

This got broken by the recent "fix rmmod $spi_driver while spidev-user is
active".  I tested the rmmod & write path but didn't check the read path.
I am sorry.  The read logic changed and spidev_sync_read() +
spidev_sync_write() do not return zero on success anymore but the number
of bytes that has been transfered over the bus.  This patch changes the
logic and copy_to_user() gets called again.

The write path returns the number of bytes which are written to the
underlying device what may be less than the requested size.  This patch
makes the same change to the read path or else we request a read of 20
bytes, get 10, don't call copy to user and report to the user that we read
10 bytes.

[akpm@linux-foundation.org: remove test of known-to-be-zero local]
Signed-off-by: Sebastian Siewior 
Acked-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi: fix refcount-related spidev oops-on-rmmod

2008-06-06T18:29:08+00:00

This addresses other oopsing paths in "spidev" by changing how it manages
refcounting.  It decouples the lifecycle of the per-device data from the
class device (not just the spi device):

  - Use class_{create,destroy} not class_{register,unregister}.
  - Use device_{create,destroy} not device_{register,unregister}.
  - Free the per-device data only when TWO conditions are true:
      * Driver is unbound from underlying SPI device, and
      * Device is no longer open (new)

Also, spi_{get,set}_drvdata not dev_{get,set}_drvdata for simpler code.

Signed-off-by: David Brownell 
Sebastian Siewior 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi: remove some spidev oops-on-rmmod paths

2008-05-24T16:56:14+00:00

Somehow the spidev code forgot to include a critical mechanism: when the
underlying device is removed (e.g.  spi_master rmmod), open file
descriptors must be prevented from issuing new I/O requests to that
device.  On penalty of the oopsing reported by Sebastian Siewior
 ...

This is a partial fix, adding handshaking between the lower level (SPI
messaging) and the file operations using the spi_dev.  (It also fixes an
issue where reads and writes didn't return the number of bytes sent or
received.)

There's still a refcounting issue to be addressed (separately).

Signed-off-by: David Brownell 
Reported-by: Sebastian Siewior 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mpc5200_psc_spi: typo fix in header block

2008-05-15T02:11:12+00:00

Signed-off-by: Grant Likely 
Acked-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi_mpc83xx: much improved driver

2008-05-13T15:02:25+00:00

The current driver may cause glitches on SPI CLK line since one must disable
the SPI controller before changing any HW settings.  Fix this by implementing
a local spi_transfer function that won't change speed and/or word size while
CS is active.

While doing that heavy lifting a few other issues were addressed too:
 - Make word size 16 and 32 work too.
 - Honor bits_per_word and speed_hz in spi transaction.
 - Optimize the common path.

This also stops using the "bitbang" framework (except for a few constants).

[Roel Kluin <12o3l@tiscali.nl>: "irq" needs to be signed]
Signed-off-by: Joakim Tjernlund 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi: pxa2xx_spi clock resume bugfix

2008-05-13T15:02:23+00:00

There is a typo in pxa2xx_spi.c, comment says "Enable the SSP clock", code
says: clk_disable ...  so after resume, the SSP is dead.

Signed-off-by: David Brownell 
Cc: Ned Forrester 
Cc: Stephen Street 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds