• Geert Uytterhoeven's avatar
    dmaengine: shdma: Move DMA stop to (runtime) suspend callbacks · b6d1778b
    Geert Uytterhoeven authored
    During system reboot, the sh-dma-engine device may be runtime-suspended,
    causing a crash:
    
        Unhandled fault: imprecise external abort (0x1406) at 0x0002c02c
        Internal error: : 1406 [#1] SMP ARM
        ...
        PC is at sh_dmae_ctl_stop+0x28/0x64
        LR is at sh_dmae_ctl_stop+0x24/0x64
    
    If the sh-dma-engine is runtime-suspended, its module clock is turned
    off, and its registers cannot be accessed.
    
    To fix this, move the call to sh_dmae_ctl_stop(), which touches the
    DMAOR register, to the sh_dmae_suspend() and sh_dmae_runtime_suspend()
    callbacks.  This makes PM operations more symmetric, as both
    sh_dmae_resume() and sh_dmae_runtime_resume() already call sh_dmae_rst()
    to re-initialize the DMAOR register.
    
    Remove sh_dmae_shutdown(), as it became empty.
    Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
    Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
    b6d1778b
shdmac.c 24.5 KB