BUTTRESS_REG_ISR_ENABLE
isp->base + BUTTRESS_REG_ISR_ENABLE);
writel(BUTTRESS_IRQS, isp->base + BUTTRESS_REG_ISR_ENABLE);
writel(BUTTRESS_IRQS, isp->base + BUTTRESS_REG_ISR_ENABLE);
writel(BUTTRESS_IRQS, isp->base + BUTTRESS_REG_ISR_ENABLE);
writel(0, isp->base + BUTTRESS_REG_ISR_ENABLE);