1. 19 Oct, 2017 1 commit
  2. 09 Feb, 2016 1 commit
  3. 13 Aug, 2015 1 commit
    • Linus Walleij's avatar
      gpio/ABI: document what is already the case · 77a775b7
      Linus Walleij authored
      commit 926b663c
      
      
      "gpiolib: allow GPIOs to be named" added the ability to
      name GPIO lines by an array of names stored in the GPIO
      chip. This was in 2009 and has been an ABI since. Let's
      document it properly.
      
      Cc: Daniel Silverstone <dsilvers@digital-scurf.org>
      Cc: Markus Pargmann <mpa@pengutronix.de>
      Cc: Johan Hovold <johan@kernel.org>
      Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
      Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      77a775b7
  4. 23 Sep, 2009 1 commit
    • Daniel Glöckner's avatar
      gpiolib: allow poll() on value · ff77c352
      Daniel Glöckner authored
      
      
      Many gpio chips allow to generate interrupts when the value of a pin
      changes.  This patch gives usermode application the opportunity to make
      use of this feature by calling poll(2) on the /sys/class/gpio/gpioN/value
      sysfs file.  The edge to trigger can be set in the edge file in the same
      directory.  Possible values are "none", "rising", "falling", and "both".
      
      Using level triggers is not possible with current sysfs since nothing
      changes the GPIO value (and the IRQ keeps triggering).  Edge triggering
      will "just work".  Note that if there was an event between read() and
      poll(), the poll() returns immediately.
      
      Also note that this version only supports true GPIO interrupts.  Some
      later patch might be able to synthesize this behavior by timer-driven
      polling; some systems seem to need that.
      
      [dbrownell@users.sourceforge.net: align ids to 16 bit ids; whitespace]
      Signed-off-by: default avatarDaniel Glöckner <dg@emlix.com>
      Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ff77c352
  5. 13 Sep, 2008 1 commit