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上一次同步 大约 4 年

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  1. 17 3月, 2011 1 次提交
  3. 24 12月, 2010 1 次提交
  5. 01 12月, 2010 2 次提交
  7. 12 11月, 2010 1 次提交
  9. 28 10月, 2010 1 次提交
  11. 22 10月, 2010 1 次提交
  13. 21 9月, 2010 1 次提交
  15. 09 9月, 2010 1 次提交
  17. 26 8月, 2010 1 次提交
  19. 18 8月, 2010 1 次提交
  21. 11 8月, 2010 1 次提交
  23. 04 7月, 2010 2 次提交
  25. 29 6月, 2010 1 次提交
    • E
      spi/mmc_spi: SPI bus locking API, using mutex · cf32b71e
      由 Ernst Schwab 提交于 
      SPI bus locking API to allow exclusive access to the SPI bus, especially, but
not limited to, for the mmc_spi driver.

Coded according to an outline from Grant Likely; here is his
specification (accidentally swapped function names corrected):

It requires 3 things to be added to struct spi_master.
- 1 Mutex
- 1 spin lock
- 1 flag.

The mutex protects spi_sync, and provides sleeping "for free"
The spinlock protects the atomic spi_async call.
The flag is set when the lock is obtained, and checked while holding
the spinlock in spi_async().  If the flag is checked, then spi_async()
must fail immediately.

The current runtime API looks like this:
spi_async(struct spi_device*, struct spi_message*);
spi_sync(struct spi_device*, struct spi_message*);

The API needs to be extended to this:
spi_async(struct spi_device*, struct spi_message*)
spi_sync(struct spi_device*, struct spi_message*)
spi_bus_lock(struct spi_master*)  /* although struct spi_device* might
be easier */
spi_bus_unlock(struct spi_master*)
spi_async_locked(struct spi_device*, struct spi_message*)
spi_sync_locked(struct spi_device*, struct spi_message*)

Drivers can only call the last two if they already hold the spi_master_lock().

spi_bus_lock() obtains the mutex, obtains the spin lock, sets the
flag, and releases the spin lock before returning.  It doesn't even
need to sleep while waiting for "in-flight" spi_transactions to
complete because its purpose is to guarantee no additional
transactions are added.  It does not guarantee that the bus is idle.

spi_bus_unlock() clears the flag and releases the mutex, which will
wake up any waiters.

The difference between spi_async() and spi_async_locked() is that the
locked version bypasses the check of the lock flag.  Both versions
need to obtain the spinlock.

The difference between spi_sync() and spi_sync_locked() is that
spi_sync() must hold the mutex while enqueuing a new transfer.
spi_sync_locked() doesn't because the mutex is already held.  Note
however that spi_sync must *not* continue to hold the mutex while
waiting for the transfer to complete, otherwise only one transfer
could be queued up at a time!

Almost no code needs to be written.  The current spi_async() and
spi_sync() can probably be renamed to __spi_async() and __spi_sync()
so that spi_async(), spi_sync(), spi_async_locked() and
spi_sync_locked() can just become wrappers around the common code.

spi_sync() is protected by a mutex because it can sleep
spi_async() needs to be protected with a flag and a spinlock because
it can be called atomically and must not sleep
Signed-off-by: NErnst Schwab <eschwab@online.de>
[grant.likely@secretlab.ca: use spin_lock_irqsave()]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NMatt Fleming <matt@console-pimps.org>
Tested-by: NAntonio Ospite <ospite@studenti.unina.it>
      cf32b71e
  27. 28 6月, 2010 1 次提交
  29. 25 5月, 2010 1 次提交
    • H
      spi: move bitbang txrx utility functions to private header · 41c4221c
      由 hartleys 提交于 
      A number of files in drivers/spi fail checkincludes.pl due to the double
include of <linux/spi/spi_bitbang.h>.

The first include is needed to get the struct spi_bitbang definition and
the spi_bitbang_* function prototypes.

The second include happens after defining EXPAND_BITBANG_TXRX to get the
inlined bitbang_txrx_* utility functions.

The <linux/spi/spi_bitbang.h> header is also included by a number of other
spi drivers, as well as some arch/ code, in order to use struct spi_bitbang
and the associated functions.

To fix the double include, and remove any potential confusion about it, move
the inlined bitbang_txrx_* functions to a new private header in drivers/spi
and also remove the need to define EXPAND_BITBANG_TXRX.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
      41c4221c
  31. 17 4月, 2010 1 次提交
  33. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      由 Tejun Heo 提交于 
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  35. 17 3月, 2010 1 次提交
    • A
      backlight: Add Epson L4F00242T03 LCD driver · e7fb9c4a
      由 Alberto Panizzo 提交于 
      The Epson LCD L4F00242T03 is mounted on the Freescale i.MX31 PDK board. 
Based upon Marek Vasut work in l4f00242t03.c, this driver provides
basic init and power on/off functionality for this device through the
sysfs lcd interface.

Unfortunately Datasheet for this device are not available and
all the control sequences sent to the display were copied from the
freescale driver that in the i.MX31 Linux BSP.

As in the i.MX31PDK board the core and io suppliers are voltage
regulators, that functionality is embedded here, but not strict.
Signed-off-by: NAlberto Panizzo <maramaopercheseimorto@gmail.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>
      e7fb9c4a
  37. 11 3月, 2010 1 次提交
  39. 10 3月, 2010 1 次提交
  41. 07 3月, 2010 1 次提交
  43. 21 1月, 2010 2 次提交
  45. 19 1月, 2010 1 次提交
  47. 17 12月, 2009 1 次提交
  49. 13 12月, 2009 1 次提交
    • M
      spi: SuperH MSIOF SPI Master driver V2 · 8051effc
      由 Magnus Damm 提交于 
      This patch is V2 of SPI Master support for the SuperH MSIOF.
Full duplex, spi mode 0-3, active high cs, 3-wire and lsb
first should all be supported, but the driver has so far
only been tested with "mmc_spi".

The MSIOF hardware comes with 32-bit FIFOs for receive and
transmit, and this driver simply breaks the SPI messages
into FIFO-sized chunks. The MSIOF hardware manages the pins
for clock, receive and transmit (sck/miso/mosi), but the chip
select pin is managed by software and must be configured as
a regular GPIO pin by the board code.

Performance wise there is still room for improvement, but
on a Ecovec board with the built-in sh7724 MSIOF0 this driver
gets Mini-sd read speeds of about half a megabyte per second.

Future work include better clock setup and merging of 8-bit
transfers into 32-bit words to reduce interrupt load and
improve throughput.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
      8051effc
  51. 09 12月, 2009 4 次提交
  53. 19 11月, 2009 1 次提交
  55. 09 11月, 2009 1 次提交
  57. 05 11月, 2009 1 次提交
  59. 23 9月, 2009 4 次提交
  61. 07 9月, 2009 1 次提交