drm: dp helper: extract drm_dp_channel_eq_ok
radeon and intel use the exact same definition.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index bb4eaf6..1378b78 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -205,3 +205,53 @@
return error;
}
EXPORT_SYMBOL(i2c_dp_aux_add_bus);
+
+/* Helpers for DP link training */
+static u8 dp_link_status(u8 link_status[DP_LINK_STATUS_SIZE], int r)
+{
+ return link_status[r - DP_LANE0_1_STATUS];
+}
+
+static u8 dp_get_lane_status(u8 link_status[DP_LINK_STATUS_SIZE],
+ int lane)
+{
+ int i = DP_LANE0_1_STATUS + (lane >> 1);
+ int s = (lane & 1) * 4;
+ u8 l = dp_link_status(link_status, i);
+ return (l >> s) & 0xf;
+}
+
+bool drm_dp_channel_eq_ok(u8 link_status[DP_LINK_STATUS_SIZE],
+ int lane_count)
+{
+ u8 lane_align;
+ u8 lane_status;
+ int lane;
+
+ lane_align = dp_link_status(link_status,
+ DP_LANE_ALIGN_STATUS_UPDATED);
+ if ((lane_align & DP_INTERLANE_ALIGN_DONE) == 0)
+ return false;
+ for (lane = 0; lane < lane_count; lane++) {
+ lane_status = dp_get_lane_status(link_status, lane);
+ if ((lane_status & DP_CHANNEL_EQ_BITS) != DP_CHANNEL_EQ_BITS)
+ return false;
+ }
+ return true;
+}
+EXPORT_SYMBOL(drm_dp_channel_eq_ok);
+
+bool drm_dp_clock_recovery_ok(u8 link_status[DP_LINK_STATUS_SIZE],
+ int lane_count)
+{
+ int lane;
+ u8 lane_status;
+
+ for (lane = 0; lane < lane_count; lane++) {
+ lane_status = dp_get_lane_status(link_status, lane);
+ if ((lane_status & DP_LANE_CR_DONE) == 0)
+ return false;
+ }
+ return true;
+}
+EXPORT_SYMBOL(drm_dp_clock_recovery_ok);