+
+ /* DP_SET_POWER register is only available on DPCD v1.1 and later */
+ if (ctrl->dpcd[DP_DPCD_REV] >= 0x11) {
+ ret = drm_dp_dpcd_readb(ctrl->drm_aux, DP_SET_POWER, &value);
+ if (ret < 0)
+ goto fail;
+
+ value &= ~DP_SET_POWER_MASK;
+ value |= DP_SET_POWER_D0;
+
+ ret = drm_dp_dpcd_writeb(ctrl->drm_aux, DP_SET_POWER, value);
+ if (ret < 0)
+ goto fail;
+
+ /*
+ * According to the DP 1.1 specification, a "Sink Device must
+ * exit the power saving state within 1 ms" (Section 2.5.3.1,
+ * Table 5-52, "Sink Control Field" (register 0x600).
+ */
+ usleep_range(1000, 2000);
+ }