drm/nouveau: register a drm_dp_aux channel for each dp connector

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

2 files changed, 55 insertions, 3 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 80ab3a1a44c1..7535a8700fe9 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -105,6 +105,8 @@ nouveau_connector_destroy(struct drm_connector *connector)
         kfree(nv_connector->edid);
         drm_sysfs_connector_remove(connector);
         drm_connector_cleanup(connector);
+        if (nv_connector->aux.transfer)
+                drm_dp_aux_unregister(&nv_connector->aux);
         kfree(connector);
 }
 
@@ -946,6 +948,38 @@ nouveau_connector_hotplug(void *data, u32 type, int index)
         return NVKM_EVENT_DROP;
 }
 
+static ssize_t
+nouveau_connector_aux_xfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
+{
+        struct nouveau_connector *nv_connector =
+                container_of(aux, typeof(*nv_connector), aux);
+        struct nouveau_encoder *nv_encoder;
+        struct nouveau_i2c_port *port;
+        int ret;
+
+        nv_encoder = find_encoder(&nv_connector->base, DCB_OUTPUT_DP);
+        if (!nv_encoder || !(port = nv_encoder->i2c))
+                return -ENODEV;
+        if (WARN_ON(msg->size > 16))
+                return -E2BIG;
+        if (msg->size == 0)
+                return msg->size;
+
+        ret = nouveau_i2c(port)->acquire(port, 0);
+        if (ret)
+                return ret;
+
+        ret = port->func->aux(port, false, msg->request, msg->address,
+                              msg->buffer, msg->size);
+        nouveau_i2c(port)->release(port);
+        if (ret >= 0) {
+                msg->reply = ret;
+                return msg->size;
+        }
+
+        return ret;
+}
+
 static int
 drm_conntype_from_dcb(enum dcb_connector_type dcb)
 {
@@ -1066,8 +1100,8 @@ nouveau_connector_create(struct drm_device *dev, int index)
                 }
         }
 
-        type = drm_conntype_from_dcb(nv_connector->type);
-        if (type == DRM_MODE_CONNECTOR_LVDS) {
+        switch ((type = drm_conntype_from_dcb(nv_connector->type))) {
+        case DRM_MODE_CONNECTOR_LVDS:
                 ret = nouveau_bios_parse_lvds_table(dev, 0, &dummy, &dummy);
                 if (ret) {
                         NV_ERROR(drm, "Error parsing LVDS table, disabling\n");
@@ -1076,8 +1110,23 @@ nouveau_connector_create(struct drm_device *dev, int index)
                 }
 
                 funcs = &nouveau_connector_funcs_lvds;
-        } else {
+                break;
+        case DRM_MODE_CONNECTOR_DisplayPort:
+        case DRM_MODE_CONNECTOR_eDP:
+                nv_connector->aux.dev = dev->dev;
+                nv_connector->aux.transfer = nouveau_connector_aux_xfer;
+                ret = drm_dp_aux_register(&nv_connector->aux);
+                if (ret) {
+                        NV_ERROR(drm, "failed to register aux channel\n");
+                        kfree(nv_connector);
+                        return ERR_PTR(ret);
+                }
+
                 funcs = &nouveau_connector_funcs;
+                break;
+        default:
+                funcs = &nouveau_connector_funcs;
+                break;
         }
 
         /* defaults, will get overridden in detect() */
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.h b/drivers/gpu/drm/nouveau/nouveau_connector.h
index 7e7682dfa991..8861b6c579ad 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.h
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.h
@@ -28,6 +28,7 @@
 #define __NOUVEAU_CONNECTOR_H__
 
 #include <drm/drm_edid.h>
+#include <drm/drm_dp_helper.h>
 #include "nouveau_crtc.h"
 
 #include <core/event.h>
@@ -70,6 +71,8 @@ struct nouveau_connector {
         u32 status;
         struct work_struct work;
 
+        struct drm_dp_aux aux;
+
         int dithering_mode;
         int dithering_depth;
         int scaling_mode;