[edk2-devel] [PATCH edk2-platforms v4 04/24] Silicon/Maxim: Fix bug in RtcWrite in Ds1307RtcLib

[Pankaj Bansal]

From: Pankaj Bansal <pankaj.bansal at nxp.com>

There was a bug in I2C DXE implementation, which caused the Ds1307 RTC
device to issue two operation for register write, while this is a single
operation task. refer page 12 (Slave Receiver Mode (Write Mode)) on

https://datasheets.maximintegrated.com/en/ds/DS1307.pdf

Modify ds1307 RtcWrite code accordingly.

Signed-off-by: Pankaj Bansal <pankaj.bansal at nxp.com>
Reviewed-by: Leif Lindholm <leif at nuviainc.com>
---

Notes:
    V4:
    - No change
    
    V3:
    - No change

 Silicon/Maxim/Library/Ds1307RtcLib/Ds1307RtcLib.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/Silicon/Maxim/Library/Ds1307RtcLib/Ds1307RtcLib.c b/Silicon/Maxim/Library/Ds1307RtcLib/Ds1307RtcLib.c
index 88dc198ffec8..fd7a8696e405 100644
--- a/Silicon/Maxim/Library/Ds1307RtcLib/Ds1307RtcLib.c
+++ b/Silicon/Maxim/Library/Ds1307RtcLib/Ds1307RtcLib.c
@@ -5,7 +5,7 @@
   EmbeddedPkg/Library/TemplateRealTimeClockLib/RealTimeClockLib.c
 
   Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
-  Copyright 2017 NXP
+  Copyright 2017, 2020 NXP
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -84,16 +84,15 @@ RtcWrite (
 {
   RTC_I2C_REQUEST          Req;
   EFI_STATUS               Status;
+  UINT8                    Buffer[2];
 
-  Req.OperationCount = 2;
+  Req.OperationCount = 1;
+  Buffer[0] = RtcRegAddr;
+  Buffer[1] = Val;
 
   Req.SetAddressOp.Flags = 0;
-  Req.SetAddressOp.LengthInBytes = sizeof (RtcRegAddr);
-  Req.SetAddressOp.Buffer = &RtcRegAddr;
-
-  Req.GetSetDateTimeOp.Flags = 0;
-  Req.GetSetDateTimeOp.LengthInBytes = sizeof (Val);
-  Req.GetSetDateTimeOp.Buffer = &Val;
+  Req.SetAddressOp.LengthInBytes = sizeof (Buffer);
+  Req.SetAddressOp.Buffer = Buffer;
 
   Status = mI2cMaster->StartRequest (mI2cMaster, FixedPcdGet8 (PcdI2cSlaveAddress),
                                      (VOID *)&Req,
-- 
2.17.1


-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#58371): https://edk2.groups.io/g/devel/message/58371
Mute This Topic: https://groups.io/mt/73370123/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub  [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-