Hi Andrzej and Brian

On 16/9/19 12:02, Andrzej Hajda wrote:

On 15.08.2019 02:48, Brian Masney wrote:

quoted

When attempting to configure this driver on a Nexus 5 phone (msm8974),
setting up the dummy i2c bus for TX_P0 would fail due to an -EBUSY
error. The downstream MSM kernel sources [1] shows that the proper value
for TX_P0 is 0x78, not 0x70, so correct the value to allow device
probing to succeed.

[1] https://github.com/AICP/kernel_lge_hammerhead/blob/n7.1/drivers/video/slimport/slimport_tx_reg.h

Signed-off-by: Brian Masney <redacted>
---
 drivers/gpu/drm/bridge/analogix-anx78xx.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/analogix-anx78xx.h b/drivers/gpu/drm/bridge/analogix-anx78xx.h
index 25e063bcecbc..bc511fc605c9 100644
--- a/drivers/gpu/drm/bridge/analogix-anx78xx.h
+++ b/drivers/gpu/drm/bridge/analogix-anx78xx.h

@@ -6,7 +6,7 @@
 #ifndef __ANX78xx_H
 #define __ANX78xx_H
 
-#define TX_P0				0x70
+#define TX_P0				0x78

This bothers me little. There are no upstream users, grepping android
sources suggests that both values can be used [1][2]  (grep for "#define
TX_P0"), moreover there is code suggesting both values can be valid [3].

Could you verify datasheet which i2c slave addresses are valid for this
chip, if both I guess this patch should be reworked.

On my case the valid i2c slave address is 0x70 (from datasheet, very sorry I
can't share it) and the bridge used is an ANX7814, it could be that ANX7808 or
ANX7812 have different slave addresses?

Regards,
 Enric

[1]:
https://android.googlesource.com/kernel/msm/+/android-msm-flo-3.4-jb-mr2/drivers/misc/slimport_anx7808/slimport_tx_reg.h

[2]:
https://github.com/AndroidGX/SimpleGX-MM-6.0_H815_20d/blob/master/drivers/video/slimport/anx7812/slimport7812_tx_reg.h

[3]:
https://github.com/commaai/android_kernel_leeco_msm8996/blob/master/drivers/video/msm/mdss/dp/slimport_custom_declare.h#L73


Regards

Andrzej

quoted

 #define TX_P1				0x7a
 #define TX_P2				0x72