Re: [PATCH] drm/bridge: Fix lvds-encoder since the panel_bridge rework.

From: Archit Taneja
Date: Thu Nov 30 2017 - 01:47:29 EST




On 11/15/2017 03:29 PM, Lothar WaÃmann wrote:
Hi,

On Tue, 14 Nov 2017 11:16:47 -0800 Eric Anholt wrote:
The panel_bridge bridge attaches to the panel's OF node, not the
lvds-encoder's node. Put in a little no-op bridge of our own so that
our consumers can still find a bridge where they expect.

This also fixes an unintended unregistration and leak of the
panel-bridge on module remove.

Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
Fixes: 13dfc0540a57 ("drm/bridge: Refactor out the panel wrapper from the lvds-encoder bri
dge.")
---

Note: I haven't actually tested this patch! Hope it helps, though.

drivers/gpu/drm/bridge/lvds-encoder.c | 48 ++++++++++++++++++++++++++++++-----
1 file changed, 41 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/bridge/lvds-encoder.c b/drivers/gpu/drm/bridge/lvds-encoder.c
index 0903ba574f61..75b0d3f6e4de 100644
--- a/drivers/gpu/drm/bridge/lvds-encoder.c
+++ b/drivers/gpu/drm/bridge/lvds-encoder.c
@@ -13,13 +13,37 @@
#include <linux/of_graph.h>
+struct lvds_encoder {
+ struct drm_bridge bridge;
+ struct drm_bridge *panel_bridge;
+};
+
+static int lvds_encoder_attach(struct drm_bridge *bridge)
+{
+ struct lvds_encoder *lvds_encoder = container_of(bridge,
+ struct lvds_encoder,
+ bridge);
+
+ return drm_bridge_attach(bridge->encoder, lvds_encoder->panel_bridge,
+ bridge);
+}
+
+static struct drm_bridge_funcs funcs = {
+ .attach = lvds_encoder_attach,
+};
+
static int lvds_encoder_probe(struct platform_device *pdev)
{
struct device_node *port;
struct device_node *endpoint;
struct device_node *panel_node;
struct drm_panel *panel;
- struct drm_bridge *bridge;
+ struct lvds_encoder *lvds_encoder;
+
+ lvds_encoder = devm_kzalloc(&pdev->dev, sizeof(*lvds_encoder),
+ GFP_KERNEL);
+ if (!lvds_encoder)
+ return -ENOMEM;
/* Locate the panel DT node. */
port = of_graph_get_port_by_id(pdev->dev.of_node, 1);
@@ -49,20 +73,30 @@ static int lvds_encoder_probe(struct platform_device *pdev)
return -EPROBE_DEFER;
}
- bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_LVDS);
- if (IS_ERR(bridge))
- return PTR_ERR(bridge);
+ lvds_encoder->panel_bridge =
+ devm_drm_panel_bridge_add(&pdev->dev,
+ panel, DRM_MODE_CONNECTOR_LVDS);
+ if (IS_ERR(lvds_encoder->panel_bridge))
+ return PTR_ERR(lvds_encoder->panel_bridge);
+
+ /* The panel_bridge bridge is attached to the panel's of_node,
+ * but we need a bridge attached to our of_node for our user
+ * to look up.
+ */
+ lvds_encoder->bridge.of_node = pdev->dev.of_node;
+ lvds_encoder->bridge.funcs = &funcs;
+ drm_bridge_add(&lvds_encoder->bridge);
- platform_set_drvdata(pdev, bridge);
+ platform_set_drvdata(pdev, lvds_encoder);
return 0;
}
static int lvds_encoder_remove(struct platform_device *pdev)
{
- struct drm_bridge *bridge = platform_get_drvdata(pdev);
+ struct lvds_encoder *lvds_encoder = platform_get_drvdata(pdev);
- drm_bridge_remove(bridge);
+ drm_bridge_remove(&lvds_encoder->bridge);
return 0;
}

Tested-by: Lothar WaÃmann <LW@xxxxxxxxxxxxxxxxxxx>

queued to drm-misc-fixes.

I think we should send this patch for the stable kernels (v4.12+) too.

Thanks,
Archit



Lothar WaÃmann


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