1. 14 10月, 2015 1 次提交
  2. 08 8月, 2015 1 次提交
  3. 26 9月, 2014 1 次提交
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      PM / AVS: rockchip-io: add driver handling Rockchip io domains · 662a9586
      Heiko Stübner 提交于
      IO domain voltages on some Rockchip SoCs are variable but need to be
      kept in sync between the regulators and the SoC using a special
      register.
      
      A specific example using rk3288:
      - If the regulator hooked up to a pin like SDMMC0_VDD is 3.3V then
        bit 7 of GRF_IO_VSEL needs to be 0.  If the regulator hooked up to
        that same pin is 1.8V then bit 7 of GRF_IO_VSEL needs to be 1.
      
      Said another way, this driver simply handles keeping bits in the SoC's
      general register file (GRF) in sync with the actual value of a voltage
      hooked up to the pins.
      
      Note that this driver specifically doesn't include:
      - any logic for deciding what voltage we should set regulators to
      - any logic for deciding whether regulators (or internal SoC blocks)
        should have power or not have power
      
      If there were some other software that had the smarts of making
      decisions about regulators, it would work in conjunction with this
      driver.  When that other software adjusted a regulator's voltage then
      this driver would handle telling the SoC about it.  A good example is
      vqmmc for SD.  In that case the dw_mmc driver simply is told about a
      regulator.  It changes the regulator between 3.3V and 1.8V at the
      right time.  This driver notices the change and makes sure that the
      SoC is on the same page.
      Signed-off-by: NHeiko Stübner <heiko@sntech.de>
      Signed-off-by: NDoug Anderson <dianders@chromium.org>
      Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
      [khilman: fix compiler warnings]
      Signed-off-by: NKevin Hilman <khilman@linaro.org>
      662a9586