During resume don't touch SUSPENDM/RESUME bits of POWER register while restoring controller context. These bits might be changed by the controller during resume operation and so will be different than what they were during suspend. e.g. SUSPENDM bit is set by software during USB global suspend but automatically cleared by the controller during remote wakeup or during resume. Setting this bit back while restoring context causes undesired behaviour. i.e. Babble interrupt is generated and USB is broken. Signed-off-by: Roger Quadros <rogerq@xxxxxx> --- drivers/usb/musb/musb_core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index fc192ad..a501542 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -2157,11 +2157,19 @@ static void musb_restore_context(struct musb *musb) void __iomem *musb_base = musb->mregs; void __iomem *ep_target_regs; void __iomem *epio; + u8 power; musb_writew(musb_base, MUSB_FRAME, musb->context.frame); musb_writeb(musb_base, MUSB_TESTMODE, musb->context.testmode); musb_write_ulpi_buscontrol(musb->mregs, musb->context.busctl); - musb_writeb(musb_base, MUSB_POWER, musb->context.power); + + /* Don't affect SUSPENDM/RESUME bits in POWER reg */ + power = musb_readb(musb_base, MUSB_POWER); + power &= MUSB_POWER_SUSPENDM | MUSB_POWER_RESUME; + musb->context.power &= ~(MUSB_POWER_SUSPENDM | MUSB_POWER_RESUME); + power |= musb->context.power; + musb_writeb(musb_base, MUSB_POWER, power); + musb_writew(musb_base, MUSB_INTRTXE, musb->intrtxe); musb_writew(musb_base, MUSB_INTRRXE, musb->intrrxe); musb_writeb(musb_base, MUSB_INTRUSBE, musb->context.intrusbe); -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
