1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.c b/drivers/gpu/drm/nouveau/nouveau_i2c.c
index 316a3c7e6eb4..97ba89ef42a0 100644
--- a/drivers/gpu/drm/nouveau/nouveau_i2c.c
+++ b/drivers/gpu/drm/nouveau/nouveau_i2c.c
@@ -278,3 +278,37 @@ nouveau_i2c_find(struct drm_device *dev, int index)
         return i2c->chan;
 }
 
+bool
+nouveau_probe_i2c_addr(struct nouveau_i2c_chan *i2c, int addr)
+{
+        struct i2c_msg msg = {
+                .addr = addr,
+                .len = 0,
+        };
+
+        return i2c_transfer(&i2c->adapter, &msg, 1) == 1;
+}
+
+int
+nouveau_i2c_identify(struct drm_device *dev, const char *what,
+                     struct i2c_board_info *info, int index)
+{
+        struct nouveau_i2c_chan *i2c = nouveau_i2c_find(dev, index);
+        int was_locked, i;
+
+        was_locked = NVLockVgaCrtcs(dev, false);
+        NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, index);
+
+        for (i = 0; info[i].addr; i++) {
+                if (nouveau_probe_i2c_addr(i2c, info[i].addr)) {
+                        NV_INFO(dev, "Detected %s: %s\n", what, info[i].type);
+                        goto out;
+                }
+        }
+
+        NV_DEBUG(dev, "No devices found.\n");
+out:
+        NVLockVgaCrtcs(dev, was_locked);
+
+        return info[i].addr ? i : -ENODEV;
+}