linux.git/drivers/spi, branch v2.6.26-rc7

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

spi_s3c24xx signedness fix

2008-05-01T15:04:01+00:00

On Fri, Apr 18, 2008 at 09:08:55PM +0200, Julia Lawall wrote:
> I found 63 occurrences of this problem with the following semantic match
> (http://www.emn.fr/x-info/coccinelle/):
>
> @@ unsigned int i; @@
>
> * i < 0
>

Since this one's always in the range 0-255, it could probably be made
signed, but it's just as easy to make it work unsigned.

Reported-by: Julia Lawall 
Signed-off-by: Matthew Wilcox 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi_bfin5xx: use PIO for full duplex, not DMA

2008-05-01T15:04:01+00:00

Use PIO for full-duplex transfers, instead of DMA.

Signed-off-by: Vitja Makarov 
Signed-off-by: Bryan Wu 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

atmel_spi: clean up baud rate divisor calculation

2008-04-30T15:29:31+00:00

Make the baud rate divisor calculation code a bit more readable and add a
few comments.

Also fix wrong debug information being displayed when !new_1 and
max_speed_hz == 0.

[david-b@pacbell.net: fix it]
Signed-off-by: Haavard Skinnemoen 
Cc: "Janesh Ramakrishnan" 
Acked-by David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

spi: spi_imx updates

2008-04-28T15:58:31+00:00

Updates to the i.MX SPI controller driver:

 1) Some comments changed and/or added.

 2) End of transfers is now managed on TXFIFO empty interrupt after the
    last write to TXFIFO.  This speeds interrupt execution by removing
    the wait for TXFIFO to become empty.  On TXFIFO empty interrupt the
    handler needs only to poll for the end of the ongoing transaction
    (SPI_CONTROL_XCH) to close the transfer.
     (2.1) Write only transfers are closed flushing RXFIFO.
     (2.2) Read transfers are closed reading trailing bytes from RXFIFO.
     (2.3) Read transfers where RXFIFO overrun occurred are closed by
           flushing RXFIFO and aborting the message.

 3) Fifos are now flushed via SPI disable after the end of ongoing
    transaction.

Signed-off-by: Andrea Paterniani 
Signed-off-by: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

atmel_spi: support zero length transfer

2008-04-28T15:58:31+00:00

A spi transfer with zero length is not invalid.  For example, such
transfer (len == 0 && delay_usecs != 0) can be used to achieve delay
before first CLK edge after chipselect assertion.

Signed-off-by: Atsushi Nemoto 
Cc: Haavard Skinnemoen 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds