[PATCH v2 3/5] [RFT] ARM: dts: wheat: Fix ADV7513 address usage

Kieran Bingham kbingham at kernel.org
Mon Feb 12 10:11:55 PST 2018


From: Kieran Bingham <kieran.bingham+renesas at ideasonboard.com>

The r8a7792 Wheat board has two ADV7513 devices sharing a single i2c
bus, however in low power mode the ADV7513 will reset it's slave maps to
use the hardware defined default addresses.

The ADV7511 driver was adapted to allow the two devices to be registered
correctly - but it did not take into account the fault whereby the
devices reset the addresses.

This results in an address conflict between the device using the default
addresses, and the other device if it is in low-power-mode.

Repair this issue by moving both devices away from the default address
definitions.

Signed-off-by: Kieran Bingham <kieran.bingham+renesas at ideasonboard.com>
---
 arch/arm/boot/dts/r8a7792-wheat.dts | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/r8a7792-wheat.dts b/arch/arm/boot/dts/r8a7792-wheat.dts
index b9471b67b728..c94f330392ee 100644
--- a/arch/arm/boot/dts/r8a7792-wheat.dts
+++ b/arch/arm/boot/dts/r8a7792-wheat.dts
@@ -240,9 +240,16 @@
 	status = "okay";
 	clock-frequency = <400000>;
 
+	/*
+	 * The adv75xx resets its addresses to defaults during low power power
+	 * mode. Because we have two ADV7513 devices on the same bus, we must
+	 * change both of them away from the defaults so that they do not
+	 * conflict.
+	 */
 	hdmi at 3d {
 		compatible = "adi,adv7513";
-		reg = <0x3d>;
+		reg = <0x3d 0x2d 0x4d, 0x5d>;
+		reg-names = "main", "cec", "edid", "packet";
 
 		adi,input-depth = <8>;
 		adi,input-colorspace = "rgb";
@@ -272,7 +279,8 @@
 
 	hdmi at 39 {
 		compatible = "adi,adv7513";
-		reg = <0x39>;
+		reg = <0x39 0x29 0x49, 0x59>;
+		reg-names = "main", "cec", "edid", "packet";
 
 		adi,input-depth = <8>;
 		adi,input-colorspace = "rgb";
-- 
2.7.4




More information about the linux-arm-kernel mailing list