From: Andrey Grodzovsky <andrey.grodzov...@amd.com>

EEPROM spec requests this.

v2: Only to be done for write data transactions.

Signed-off-by: Andrey Grodzovsky <andrey.grodzov...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Reviewed-by: Luben Tuikov <luben.tui...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
index 10551660343278..fe0e9b0c4d5a38 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
@@ -55,6 +55,21 @@ int amdgpu_eeprom_xfer(struct i2c_adapter *i2c_adap,
                r = i2c_transfer(i2c_adap, msgs, ARRAY_SIZE(msgs));
                if (r <= 0)
                        return r;
+
+               /* Only for write data */
+               if (!msgs[1].flags)
+                       /*
+                        * According to EEPROM spec there is a MAX of 10 ms 
required for
+                        * EEPROM to flush internal RX buffer after STOP was 
issued at the
+                        * end of write transaction. During this time the 
EEPROM will not be
+                        * responsive to any more commands - so wait a bit more.
+                        *
+                        * TODO Improve to wait for first ACK for slave address 
after
+                        * internal write cycle done.
+                        */
+                       msleep(10);
+
+
                bytes_transferred = r - EEPROM_OFFSET_LENGTH;
                eeprom_addr += bytes_transferred;
                msgs[0].buf[0] = ((eeprom_addr >> 8) & 0xff);
-- 
2.32.0

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