• Florian Fainelli's avatar
    pinctrl: Really force states during suspend/resume · 981ed1bf
    Florian Fainelli authored
    In case a platform only defaults a "default" set of pins, but not a
    "sleep" set of pins, and this particular platform suspends and resumes
    in a way that the pin states are not preserved by the hardware, when we
    resume, we would call pinctrl_single_resume() -> pinctrl_force_default()
    -> pinctrl_select_state() and the first thing we do is check that the
    pins state is the same as before, and do nothing.
    
    In order to fix this, decouple the actual state change from
    pinctrl_select_state() and move it pinctrl_commit_state(), while keeping
    the p->state == state check in pinctrl_select_state() not to change the
    caller assumptions. pinctrl_force_sleep() and pinctrl_force_default()
    are updated to bypass the state check by calling pinctrl_commit_state().
    
    [Linus Walleij]
    The forced pin control states are currently only used in some pin
    controller drivers that grab their own reference to their own pins.
    This is equal to the pin control hogs: pins taken by pin control
    devices since there are no corresponding device in the Linux device
    hierarchy, such as memory controller lines or unused GPIO lines,
    or GPIO lines that are used orthogonally from the GPIO subsystem
    but pincontrol-wise managed as hogs (non-strict mode, allowing
    simultaneous use by GPIO and pin control). For this case forcing
    the state from the drivers' suspend()/resume() callbacks makes
    sense and should semantically match the name of the function.
    
    Fixes: 6e5e959d ("pinctrl: API changes to support multiple states per device")
    Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
    Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
    Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    981ed1bf
core.c 56.7 KB