1. 18 Oct, 2019 2 commits
    • William Breathitt Gray's avatar
      bitops: introduce the for_each_set_clump8 macro · f6df8d7c
      William Breathitt Gray authored
      Pach series "Introduce the for_each_set_clump8 macro", v18.
      
      While adding GPIO get_multiple/set_multiple callback support for various
      drivers, I noticed a pattern of looping manifesting that would be useful
      standardized as a macro.
      
      This patchset introduces the for_each_set_clump8 macro and utilizes it in
      several GPIO drivers.  The for_each_set_clump macro8 facilitates a
      for-loop syntax that iterates over a memory region entire groups of set
      bits at a time.
      
      For example, suppose you would like to iterate over a 32-bit integer 8
      bits at a time, skipping over 8-bit groups with no set bit, where XXXXXXXX
      represents the current 8-bit group:
      
          Example:        10111110 00000000 11111111 00110011
          First loop:     10111110 00000000 11111111 XXXXXXXX
          Second loop:    10111110 00000000 XXXXXXXX 00110011
          Third loop:     XXXXXXXX 00000000 11111111 00110011
      
      Each iteration of the loop returns the next 8-bit group that has at
      least one set bit.
      
      The for_each_set_clump8 macro has four parameters:
      
          * start: set to the bit offset of the current clump
          * clump: set to the current clump value
          * bits: bitmap to search within
          * size: bitmap size in number of bits
      
      In this version of the patchset, the for_each_set_clump macro has been
      reimplemented and simplified based on the suggestions provided by Rasmus
      Villemoes and Andy Shevchenko in the version 4 submission.
      
      In particular, the function of the for_each_set_clump macro has been
      restricted to handle only 8-bit clumps; the drivers that use the
      for_each_set_clump macro only handle 8-bit ports so a generic
      for_each_set_clump implementation is not necessary.  Thus, a solution for
      large clumps (i.e.  those larger than the width of a bitmap word) can be
      postponed until a driver appears that actually requires such a generic
      for_each_set_clump implementation.
      
      For what it's worth, a semi-generic for_each_set_clump (i.e.  for clumps
      smaller than the width of a bitmap word) can be implemented by simply
      replacing the hardcoded '8' and '0xFF' instances with respective
      variables.  I have not yet had a need for such an implementation, and
      since it falls short of a true generic for_each_set_clump function, I have
      decided to forgo such an implementation for now.
      
      In addition, the bitmap_get_value8 and bitmap_set_value8 functions are
      introduced to get and set 8-bit values respectively.  Their use is based
      on the behavior suggested in the patchset version 4 review.
      
      This patch (of 14):
      
      This macro iterates for each 8-bit group of bits (clump) with set bits,
      within a bitmap memory region.  For each iteration, "start" is set to the
      bit offset of the found clump, while the respective clump value is stored
      to the location pointed by "clump".  Additionally, the bitmap_get_value8
      and bitmap_set_value8 functions are introduced to respectively get and set
      an 8-bit value in a bitmap memory region.
      
      Link: http://lkml.kernel.org/r/893c3b4f03266c9496137cc98ac2b1bd27f92c73.1570641097.git.vilhelm.gray@gmail.comSigned-off-by: default avatarWilliam Breathitt Gray <vilhelm.gray@gmail.com>
      Suggested-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
      Suggested-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
      Suggested-by: default avatarLukas Wunner <lukas@wunner.de>
      Tested-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Linus Walleij <linus.walleij@linaro.org>
      Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Phil Reid <preid@electromag.com.au>
      Cc: Geert Uytterhoeven <geert+renesas@glider.be>
      Cc: Mathias Duckeck <m.duckeck@kunbus.de>
      Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
      Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      f6df8d7c
    • Huang Shijie's avatar
      lib/genalloc.c: rename addr_in_gen_pool to gen_pool_has_addr · be3f54b7
      Huang Shijie authored
      Follow the kernel conventions, rename addr_in_gen_pool to
      gen_pool_has_addr.
      
      Link: http://lkml.kernel.org/r/20181228083950.20398-1-sjhuang@iluvatar.aiSigned-off-by: default avatarHuang Shijie <sjhuang@iluvatar.ai>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Marek Szyprowski <m.szyprowski@samsung.com>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      be3f54b7
  2. 17 Oct, 2019 33 commits
  3. 16 Oct, 2019 5 commits