[RFC PATCH 02/17] drm/exynos: dsi: Handle drm_device for bridge

[Jagan Teki]

Now the exynos dsi driver supports bridge and legacy
encoder.

In order to support drm_device in both the implementations
it is required to preserve the drm_device in a private
structure and use it accordingly.

1. encoder case, the bind will assign the drm_device into
   encoder->dev, so preserve the drm_device in the bind call.

2. bridge case, the drm_bridge_attach will assign the
   drm_device into bridge->dev, so preserve the drm_device
   in the bridge_attach function call.

Signed-off-by: Jagan Teki <ja...@amarulasolutions.com>
---
 drivers/gpu/drm/exynos/exynos_drm_dsi.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c 
b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index 90d2ce2c3055..d7d60aee465b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -259,6 +259,7 @@ struct exynos_dsi {
        struct list_head bridge_chain;
        struct drm_bridge bridge;
        struct drm_bridge *out_bridge;
+       struct drm_device *drm;
        struct device *dev;
 
        void __iomem *reg_base;
@@ -1495,11 +1496,11 @@ static const struct drm_connector_helper_funcs 
exynos_dsi_connector_helper_funcs
        .get_modes = exynos_dsi_get_modes,
 };
 
-static int exynos_dsi_create_connector(struct exynos_dsi *dsi)
+static int exynos_dsi_create_connector(struct exynos_dsi *dsi,
+                                      struct drm_device *drm)
 {
        struct drm_encoder *encoder = &dsi->encoder;
        struct drm_connector *connector = &dsi->connector;
-       struct drm_device *drm = encoder->dev;
        int ret;
 
        connector->polled = DRM_CONNECTOR_POLL_HPD;
@@ -1526,6 +1527,10 @@ static int exynos_dsi_create_connector(struct exynos_dsi 
*dsi)
 static int exynos_dsi_bridge_attach(struct drm_bridge *bridge,
                                    enum drm_bridge_attach_flags flags)
 {
+       struct exynos_dsi *dsi = bridge_to_dsi(bridge);
+
+       dsi->drm = bridge->dev;
+
        return 0;
 }
 
@@ -1542,7 +1547,7 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host 
*host,
 {
        struct exynos_dsi *dsi = host_to_dsi(host);
        struct drm_encoder *encoder = &dsi->encoder;
-       struct drm_device *drm = encoder->dev;
+       struct drm_device *drm = dsi->drm;
        struct drm_bridge *out_bridge;
 
        out_bridge  = of_drm_find_bridge(device->dev.of_node);
@@ -1551,7 +1556,7 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host 
*host,
                dsi->out_bridge = out_bridge;
                list_splice_init(&encoder->bridge_chain, &dsi->bridge_chain);
        } else {
-               int ret = exynos_dsi_create_connector(dsi);
+               int ret = exynos_dsi_create_connector(dsi, drm);
 
                if (ret) {
                        DRM_DEV_ERROR(dsi->dev,
@@ -1600,7 +1605,7 @@ static int exynos_dsi_host_detach(struct mipi_dsi_host 
*host,
                                  struct mipi_dsi_device *device)
 {
        struct exynos_dsi *dsi = host_to_dsi(host);
-       struct drm_device *drm = dsi->encoder.dev;
+       struct drm_device *drm = dsi->drm;
 
        if (dsi->panel) {
                mutex_lock(&drm->mode_config.mutex);
@@ -1728,6 +1733,8 @@ static int exynos_dsi_bind(struct device *dev, struct 
device *master,
                of_node_put(in_bridge_node);
        }
 
+       dsi->drm = drm_dev;
+
        return mipi_dsi_host_register(&dsi->dsi_host);
 }
 
-- 
2.25.1