diff options
Diffstat (limited to 'drivers/gpu/drm/msm/dp/dp_link.c')
| -rw-r--r-- | drivers/gpu/drm/msm/dp/dp_link.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c index 2aeb3ecf76fa..34a91e194a12 100644 --- a/drivers/gpu/drm/msm/dp/dp_link.c +++ b/drivers/gpu/drm/msm/dp/dp_link.c @@ -1236,6 +1236,61 @@ static u32 msm_dp_link_link_frequencies(struct device_node *of_node) return frequency; } +/* + * Always populate msm_dp_link->lane_map with 4 lanes. + * - Use DTS "data-lanes" if present; otherwise fall back to default mapping. + * - For partial definitions, fill remaining entries with unused lanes in + * ascending order. + */ +static int msm_dp_link_lane_map(struct device *dev, struct msm_dp_link *msm_dp_link) +{ + struct device_node *of_node = dev->of_node; + struct device_node *endpoint; + int cnt = msm_dp_link->max_dp_lanes; + u32 tmp[DP_MAX_NUM_DP_LANES]; + u32 map[DP_MAX_NUM_DP_LANES] = {0, 1, 2, 3}; /* default 1:1 mapping */ + bool used[DP_MAX_NUM_DP_LANES] = {false}; + int i, j = 0, ret = -EINVAL; + + endpoint = of_graph_get_endpoint_by_regs(of_node, 1, -1); + if (endpoint) { + ret = of_property_read_u32_array(endpoint, "data-lanes", tmp, cnt); + if (ret) + dev_dbg(dev, "endpoint data-lanes read failed (ret=%d)\n", ret); + } + + if (ret) { + ret = of_property_read_u32_array(of_node, "data-lanes", tmp, cnt); + if (ret) { + dev_info(dev, "data-lanes not defined, set to default\n"); + goto out; + } + } + + for (i = 0; i < cnt; i++) { + if (tmp[i] >= DP_MAX_NUM_DP_LANES) { + dev_err(dev, "data-lanes[%d]=%u out of range\n", i, tmp[i]); + return -EINVAL; + } + used[tmp[i]] = true; + map[i] = tmp[i]; + } + + /* Fill the remaining entries with unused physical lanes (ascending) */ + for (i = cnt; i < DP_MAX_NUM_DP_LANES && j < DP_MAX_NUM_DP_LANES; j++) { + if (!used[j]) + map[i++] = j; + } + +out: + if (endpoint) + of_node_put(endpoint); + + dev_dbg(dev, "data-lanes count %d <%d %d %d %d>\n", cnt, map[0], map[1], map[2], map[3]); + memcpy(msm_dp_link->lane_map, map, sizeof(map)); + return 0; +} + static int msm_dp_link_parse_dt(struct device *dev, struct msm_dp_link *msm_dp_link) { struct device_node *of_node = dev->of_node; @@ -1255,6 +1310,11 @@ static int msm_dp_link_parse_dt(struct device *dev, struct msm_dp_link *msm_dp_l else msm_dp_link->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */ + if (msm_dp_link_lane_map(dev, msm_dp_link)) { + dev_err(dev, "failed to parse data-lanes\n"); + return -EINVAL; + } + msm_dp_link->max_dp_link_rate = msm_dp_link_link_frequencies(of_node); if (!msm_dp_link->max_dp_link_rate) msm_dp_link->max_dp_link_rate = DP_LINK_RATE_HBR2; |