• Paul Kocialkowski's avatar
    pwm: twl: Reliably disable TWL6030 PWMs · 45c0ce84
    Paul Kocialkowski authored
    The current TWL6030 code for the TWL PWM driver does not reliably disable the
    PWM output, as tested with LEDs. The previous commit to that driver introduced
    that regression.
    However, it does make sense to disable the PWM clock after resetting the PWM,
    but for some obscure reason, doing it all at once simply doesn't work.
    The TWL6030 datasheet mentions that PWMs have to be disabled in two distinct
    steps. However, clearing the clock enable bit in a second step (after issuing a
    reset first) does not work.
    The only approach that works is the one that was in place before the previous
    commit to the driver. It consists in enabling the PWM clock after issuing a
    reset. This is what TI kernel trees and production code seem to be using.
    However, adding an extra step to disable the PWM clock seems to work reliably,
    despite looking quite odd.
    Signed-off-by: default avatarPaul Kocialkowski <contact@paulk.fr>
    Acked-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
    Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>