1. Dec 20, 2018
  2. Dec 19, 2018
  3. Dec 17, 2018
  4. Dec 14, 2018
  5. Dec 13, 2018
  6. Dec 12, 2018
    • Douglas Anderson's avatar
      regulator: core: Clean enabling always-on regulators + their supplies · 05f224ca
      Douglas Anderson authored
      At the end of regulator_resolve_supply() we have historically turned
      on our supply in some cases.  This could be for one of two reasons:
      
      1. If resolving supplies was happening before the call to
         set_machine_constraints() we needed to predict if
         set_machine_constraints() was going to turn the regulator on and we
         needed to preemptively turn the supply on.
      2. Maybe set_machine_constraints() happened before we could resolve
         supplies (because we failed the first time to resolve) and thus we
         might need to propagate an enable that already happened up to our
         supply.
      
      Historically regulator_resolve_supply() used _regulator_is_enabled()
      to decide whether to turn on the supply.
      
      Let's change things a little bit.  Specifically:
      
      1. Let's try to enable the supply and the regulator in the same place,
         both in set_machine_constraints().  This means that we have exactly
         the same logic for enabling the supply and the regulator.
      2. Let's properly set use_count when we enable always-on or boot-on
         regulators even for those that don't have supplies.  The previous
         commit 1fc12b05 ("regulator: core: Avoid propagating to
         supplies when possible") only did this right for regulators with
         supplies.
      3. Let's make it clear that the only time we need to enable the supply
         in regulator_resolve_supply() is if the main regulator is currently
         in use.  By using use_count (like the rest of the code) to decide
         if we're going to enable our supply we keep everything consistent.
      
      Overall the new scheme should be cleaner and easier to reason about.
      In addition to fixing regulator_summary to be more correct (because of
      the more correct use_count), this change also has the effect of no
      longer using _regulator_is_enabled() in this code path.
      _regulator_is_enabled() could return an error code for some regulators
      at bootup (like RPMh) that can't read their initial state.  While one
      can argue that the design of those regulators is sub-optimal, the new
      logic sidesteps this brokenness.  This fix in particular fixes
      observed problems on Qualcomm sdm845 boards which use the
      above-mentioned RPMh regulator.  Those problems were made worse by
      commit 1fc12b05 ("regulator: core: Avoid propagating to supplies
      when possible") because now we'd think at bootup that the SD
      regulators were already enabled and we'd never try them again.
      
      Fixes: 1fc12b05
      
       ("regulator: core: Avoid propagating to supplies when possible")
      Reported-by: default avatarEvan Green <evgreen@chromium.org>
      Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      05f224ca
    • Mark Brown's avatar
      Merge branch 'for-linus' of... · e6202e82
      Mark Brown authored
      Merge branch 'for-linus' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-4.21
      e6202e82
  7. Dec 11, 2018