[PATCH 1/2] drm/bridge/synopsys: dw-hdmi: Add an option to suppress loading CEC driver

Jernej Skrabec jernej.skrabec at siol.net
Sun Mar 24 14:21:42 PDT 2019


DW HDMI controller on some Allwinner SoCs has support for CEC, but due
to additional logic put between CEC controller and pins, it doesn't work
correctly, at least not with a lot of instrusive changes. Fortunately,
it's still possible to bitbang protocol.

For such cases, add a platform option to suppress loading CEC driver. If
DW HDMI CEC driver would be loaded, it wouldn't work anyway and only
cause a confusion with multiple /dev entries.

Signed-off-by: Jernej Skrabec <jernej.skrabec at siol.net>
---
 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 2 +-
 include/drm/bridge/dw_hdmi.h              | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index a63e5f0dae56..fdda26f8b056 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -2634,7 +2634,7 @@ __dw_hdmi_probe(struct platform_device *pdev,
 		hdmi->audio = platform_device_register_full(&pdevinfo);
 	}
 
-	if (config0 & HDMI_CONFIG0_CEC) {
+	if (!plat_data->is_cec_unusable && (config0 & HDMI_CONFIG0_CEC)) {
 		cec.hdmi = hdmi;
 		cec.ops = &dw_hdmi_cec_ops;
 		cec.irq = irq;
diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
index 66e70770cce5..764b8bcfa62c 100644
--- a/include/drm/bridge/dw_hdmi.h
+++ b/include/drm/bridge/dw_hdmi.h
@@ -144,6 +144,8 @@ struct dw_hdmi_plat_data {
 	int (*configure_phy)(struct dw_hdmi *hdmi,
 			     const struct dw_hdmi_plat_data *pdata,
 			     unsigned long mpixelclock);
+
+	unsigned int is_cec_unusable : 1;
 };
 
 struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
-- 
2.21.0




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