1. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      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: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  2. 28 Jul, 2008 1 commit
  3. 14 Jul, 2008 1 commit
    • Jean Delvare's avatar
      i2c: Let bus drivers add SPD to their class · 3401b2ff
      Jean Delvare authored
      
      
      Let general purpose I2C/SMBus bus drivers add SPD to their class. Once
      this is done, we will be able to tell the eeprom driver to only probe
      for SPD EEPROMs and similar on these buses.
      
      Note that I took a conservative approach here, adding I2C_CLASS_SPD to
      many drivers that have no idea whether they can host SPD EEPROMs or not.
      This is to make sure that the eeprom driver doesn't stop probing buses
      where SPD EEPROMs or equivalent live.
      
      So, bus driver maintainers and users should feel free to remove the SPD
      class from drivers those buses never have SPD EEPROMs or they don't
      want the eeprom driver to bind to them. Likewise, feel free to add the
      SPD class to any bus driver I might have missed.
      Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
      3401b2ff
  4. 22 Apr, 2008 1 commit
  5. 12 Dec, 2007 1 commit
  6. 09 Sep, 2007 1 commit
  7. 12 Jul, 2007 2 commits
  8. 01 May, 2007 1 commit
    • Haavard Skinnemoen's avatar
      i2c: Bitbanging I2C bus driver using the GPIO API · 1c23af90
      Haavard Skinnemoen authored
      
      
      This is a very simple bitbanging I2C bus driver utilizing the new
      arch-neutral GPIO API. Useful for chips that don't have a built-in
      I2C controller, additional I2C busses, or testing purposes.
      
      To use, include something similar to the following in the
      board-specific setup code:
      
        #include <linux/i2c-gpio.h>
      
        static struct i2c_gpio_platform_data i2c_gpio_data = {
      	.sda_pin	= GPIO_PIN_FOO,
      	.scl_pin	= GPIO_PIN_BAR,
        };
        static struct platform_device i2c_gpio_device = {
      	.name		= "i2c-gpio",
      	.id		= 0,
      	.dev		= {
      		.platform_data	= &i2c_gpio_data,
      	},
        };
      
      Register this platform_device, set up the I2C pins as GPIO if
      required and you're ready to go. This will use default values for
      udelay and timeout, and will work with GPIO hardware that does not
      support open drain mode, but allows sensing of the SDA and SCL lines
      even when they are being driven.
      Signed-off-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
      Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
      1c23af90