GPIO_INT_POLARITY
iowrite32(~0, (void __iomem *) GPIO_INT_POLARITY);
iowrite32(0xffffffff, (void __iomem *) GPIO_INT_POLARITY);
case GPIO_INT_POLARITY:
pol = dwapb_read(gpio, GPIO_INT_POLARITY);
dwapb_write(gpio, GPIO_INT_POLARITY, pol);
polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
ctx->int_pol = dwapb_read(gpio, GPIO_INT_POLARITY);
dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);