On Thu, Jan 25, 2018 at 12:27:31PM +0000, Ard Biesheuvel wrote: > Instead of registering a notification callback on the driver binding > protocol, and attempting to connect our I2C master handle each time > a new driver is registered, switch to the more obvious approach of > registering a notification callback on the I2C master protocol directly. > > The original code was written under the assumption that it would make > the RTC available at an earlier time, but given that all handles that > are created during the execution of a driver entry point are connected > by DXE core right away (i.e., before StartImage() returns), this is not > really necessary, and in fact, may result in the driver already having > been connected by the time we attempt to connect it. > > Note that it is now up to the platform to ensure that ConnectController() > is called for the handle if DXE core does not call it by itself, or does > call it but at a time when no I2C master protocol driver is available > yet.
Presumably the platforms in edk2-platforms using this library already follow these constraints? If so: Reviewed-by: Leif Lindholm <[email protected]> > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ard Biesheuvel <[email protected]> > --- > Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c | 31 > ++++++++------------ > Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf | 1 > - > 2 files changed, 13 insertions(+), 19 deletions(-) > > diff --git > a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c > b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c > index 6bc4aef28849..fb58e1feb424 100644 > --- a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c > +++ b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c > @@ -41,7 +41,7 @@ > #define EPOCH_BASE 2000 > > STATIC EFI_HANDLE mI2cMasterHandle; > -STATIC VOID *mDriverEventRegistration; > +STATIC VOID *mI2cMasterEventRegistration; > STATIC EFI_I2C_MASTER_PROTOCOL *mI2cMaster; > STATIC EFI_EVENT mRtcVirtualAddrChangeEvent; > > @@ -263,12 +263,12 @@ LibSetWakeupTime ( > > STATIC > VOID > -DriverRegistrationEvent ( > +I2cMasterRegistrationEvent ( > IN EFI_EVENT Event, > IN VOID *Context > ) > { > - EFI_HANDLE Handle[2]; > + EFI_HANDLE Handle; > UINTN BufferSize; > EFI_STATUS Status; > EFI_I2C_MASTER_PROTOCOL *I2cMaster; > @@ -280,10 +280,10 @@ DriverRegistrationEvent ( > do { > BufferSize = sizeof (EFI_HANDLE); > Status = gBS->LocateHandle (ByRegisterNotify, > - &gEfiDriverBindingProtocolGuid, > - mDriverEventRegistration, > + &gEfiI2cMasterProtocolGuid, > + mI2cMasterEventRegistration, > &BufferSize, > - Handle); > + &Handle); > if (EFI_ERROR (Status)) { > if (Status != EFI_NOT_FOUND) { > DEBUG ((DEBUG_WARN, "%a: gBS->LocateHandle () returned %r\n", > @@ -292,12 +292,7 @@ DriverRegistrationEvent ( > break; > } > > - // > - // Check if we can connect our handle to this driver. > - // > - Handle[1] = NULL; > - Status = gBS->ConnectController (mI2cMasterHandle, Handle, NULL, FALSE); > - if (EFI_ERROR (Status)) { > + if (Handle != mI2cMasterHandle) { > continue; > } > > @@ -378,16 +373,16 @@ LibRtcInitialize ( > ASSERT_EFI_ERROR (Status); > > // > - // Register a protocol registration notification callback on the driver > - // binding protocol so we can attempt to connect our I2C master to it > - // as soon as it appears. > + // Register a protocol registration notification callback on the I2C master > + // protocol. This will notify us even if the protocol instance we are > looking > + // for has already been installed. > // > EfiCreateProtocolNotifyEvent ( > - &gEfiDriverBindingProtocolGuid, > + &gEfiI2cMasterProtocolGuid, > TPL_CALLBACK, > - DriverRegistrationEvent, > + I2cMasterRegistrationEvent, > NULL, > - &mDriverEventRegistration); > + &mI2cMasterEventRegistration); > > // > // Register for the virtual address change event > diff --git > a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf > b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf > index 1a9a6f6c9cf3..e232902c6b5d 100644 > --- a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf > +++ b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf > @@ -40,7 +40,6 @@ [Guids] > gEfiEventVirtualAddressChangeGuid > > [Protocols] > - gEfiDriverBindingProtocolGuid ## CONSUMES > gEfiI2cMasterProtocolGuid ## CONSUMES > gPcf8563RealTimeClockLibI2cMasterProtocolGuid ## CONSUMES > > -- > 2.11.0 > _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
