drm/msm/dsi: Don't get DSI index from DT

The DSI host and PHY driver currently expects the DT bindings to provide
custom properties "qcom,dsi-host-index" and "qcom,dsi-phy-index" so that
the driver can identify which DSI instance it is.

The binding isn't acceptable, but the driver still needs to figure out
what its instance id. This is now done by storing the mmio starting
addresses for each DSI instance in every SoC version in the driver. The
driver then identifies the index number by trying to match the stored
address with comparing the resource start address we get from DT.

We don't have compatible strings for DSI PHY on each SoC, but only the
DSI PHY type. We only support one SoC version for each PHY type, so we
get away doing the same thing above for the PHY driver. We can revisit
this when we support two SoCs with the same DSI PHY.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

1 files changed, 28 insertions, 4 deletions

diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
index e2f42d8ea294..f39386ed75e4 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
@@ -271,6 +271,30 @@ static const struct of_device_id dsi_phy_dt_match[] = {
 	{}
 };
 
+/*
+ * Currently, we only support one SoC for each PHY type. When we have multiple
+ * SoCs for the same PHY, we can try to make the index searching a bit more
+ * clever.
+ */
+static int dsi_phy_get_id(struct msm_dsi_phy *phy)
+{
+	struct platform_device *pdev = phy->pdev;
+	const struct msm_dsi_phy_cfg *cfg = phy->cfg;
+	struct resource *res;
+	int i;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dsi_phy");
+	if (!res)
+		return -EINVAL;
+
+	for (i = 0; i < cfg->num_dsi_phy; i++) {
+		if (cfg->io_start[i] == res->start)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
 static int dsi_phy_driver_probe(struct platform_device *pdev)
 {
 	struct msm_dsi_phy *phy;
@@ -289,10 +313,10 @@ static int dsi_phy_driver_probe(struct platform_device *pdev)
 	phy->cfg = match->data;
 	phy->pdev = pdev;
 
-	ret = of_property_read_u32(dev->of_node,
-				"qcom,dsi-phy-index", &phy->id);
-	if (ret) {
-		dev_err(dev, "%s: PHY index not specified, %d\n",
+	phy->id = dsi_phy_get_id(phy);
+	if (phy->id < 0) {
+		ret = phy->id;
+		dev_err(dev, "%s: couldn't identify PHY index, %d\n",
 			__func__, ret);
 		goto fail;
 	}