26 Sep, 2014

1 commit

  • 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: Heiko Stübner
    Signed-off-by: Doug Anderson
    Reviewed-by: Santosh Shilimkar
    [khilman: fix compiler warnings]
    Signed-off-by: Kevin Hilman

    Heiko Stübner
     

01 Jun, 2012

1 commit

  • After a clean-up of the interfaces the OMAP Smartreflex IP driver is now a
    generic driver. Move it to drivers/power/avs/.

    The build is controlled by the following Kconfig options:
    . CONFIG_POWER_AVS: general knob for Adaptive Voltage Scaling support,
    . CONFIG_POWER_AVS_OMAP: AVS(Adaptive Voltage Scaling)
    support on OMAP containing the version 1 or version 2 of the SmartReflex IP,
    . CONFIG_POWER_AVS_OMAP_CLASS3: Class 3 implementation of Smartreflex.

    Signed-off-by: Jean Pihet
    Signed-off-by: J Keerthy
    Acked-by: Rafael J. Wysocki
    Reviewed-by: Kevin Hilman
    Signed-off-by: Kevin Hilman

    Jean Pihet