Hardware Resource Manager Plug-in Tutorial

Introduction

Symbian developers must implement the CHWRMPluginService in their plug-in. The HWRM plug-in must create a new instance of the CHWRMPluginServices using CHWRMPluginService::NewL() method. A string and a callback pointer are passed as the parameters. The common strings used to identify the plug-in are HWRMLight, HWRMVibra and HWRMPower. The callback pointer is provided by the MHWRMPluginCallback class.

The client APIs requests are forwarded to the plug-in using a CHWRMPluginServices::ProcessCommandL(). Command - ID, transaction ID and command data are passed as parameters. The plug-in communicates with the hardware using proprietary software developed by the licensees and convert the client requests into hardware control commands. After processing a request, the plug-in acknowledges the server by calling the MHWRMPluginCallback::ProcessResponseL() callback function. The same command ID and transaction ID are passed as the parameters. An error code is also included in the acknowledgement message.

Every MHWRMPluginCallback::ProcessResponseL() is associated with an CHWRMPluginServices::ProcessCommandL() request. Both functions can use asynchronous calls and leave. The HWRM server can cancel a CHWRMPluginServices::ProcessCommandL() request by calling a CHWRMPluginService::CancelCommandL().

Plug-in Configuration

Configure HWRM plug-ins as an ECom plug-in. To load the plug-in correctly, the resource files must be configured carefully.

The following code illustrates a sample resource file for Light and Vibra plug-ins:

-#include "RegistryInfoV2.rh" - -//Sample resource file for Light and Vibra plug-ins - -RESOURCE REGISTRY_INFO theInfo - { - resource_format_version = RESOURCE_FORMAT_VERSION_2; - dll_uid = 0x12345678; - interfaces = - { - INTERFACE_INFO - { - // UID of interface that is implemented - interface_uid = 0x10205028; - implementations = - { - IMPLEMENTATION_INFO - { - implementation_uid = 0x11223344; - version_no = 1; - display_name = "Light plugin stub"; - default_data = "HWRMLight"; - opaque_data = ""; - rom_only = 1; - }, - IMPLEMENTATION_INFO - { - implementation_uid = 0x55667788; - version_no = 1; - display_name = "Vibra plugin stub"; - default_data = "HWRMVibra"; - opaque_data = ""; - rom_only = 1; - } - }; - } - }; - }

Note: The value of rom_only must always be 1. The default data must be HWRMLight, HWRMVibra, HWRMPower.

Sample Light plug-in example

The following code snippet illustrates how a light plug-in is called by the HWRM server:

-#include "HWRMpluginService.h" - -_LIT8( KHWRMLightApiEComMatch, "HWRMLight" ); - -iPlugin = CHWRMPluginService::NewL( KHWRMLightApiEComMatch, this ); -iTransCounter = 0; -. . . -HWRMLightCommand::TLightsOnData pluginCommand; -pluginCommand.iTarget = 0x00000001; // Set target to primary display -pluginCommand.iIntensity = 50; -pluginCommand.iFadeIn = EFalse; -HWRMLightCommand::TLightsOnCmdPackage pckg( pluginCommand ); -iPlugin->ProcessCommandL( HWRMLightCommand::ELightsOnCmdId, iTransCounter++, pckg ); - -//Example of how ProcessResponseL() or EventL() might be handled - -HWRMLightCommand::TErrorCodeResponsePackage errPckg; -errPckg.Copy( aData ); -TInt pluginErr = errPckg(); - -// Handle error here + + + + + +Hardware Resource Manager Plug-in TutorialThis tutorial describes how to write the plug-ins for HWRM.

Introduction

The client APIs requests are forwarded to the plug-in using a CHWRMPluginServices::ProcessCommandL(). Command + ID, transaction ID and command data are passed as parameters. The plug-in communicates with the hardware using proprietary software developed by the licensees and convert the client requests into hardware control commands. After processing a request, the plug-in acknowledges the server by calling the MHWRMPluginCallback::ProcessResponseL() callback function. The same command ID and transaction ID are passed as the parameters. An error code is also included in the acknowledgement message.

Plug-in Configuration

Configure HWRM plug-ins as an ECom plug-in. To load the plug-in correctly, the resource files must be configured carefully.

The following code illustrates a sample resource file for Light and Vibra plug-ins:

+#include "RegistryInfoV2.rh" + +//Sample resource file for Light and Vibra plug-ins + +RESOURCE REGISTRY_INFO theInfo + { + resource_format_version = RESOURCE_FORMAT_VERSION_2; + dll_uid = 0x12345678; + interfaces = + { + INTERFACE_INFO + { + // UID of interface that is implemented + interface_uid = 0x10205028; + implementations = + { + IMPLEMENTATION_INFO + { + implementation_uid = 0x11223344; + version_no = 1; + display_name = "Light plugin stub"; + default_data = "HWRMLight"; + opaque_data = ""; + rom_only = 1; + }, + IMPLEMENTATION_INFO + { + implementation_uid = 0x55667788; + version_no = 1; + display_name = "Vibra plugin stub"; + default_data = "HWRMVibra"; + opaque_data = ""; + rom_only = 1; + } + }; + } + }; + }

Note: The value of rom_only must always be 1. The default data must be HWRMLight, HWRMVibra, HWRMPower.

Sample Light plug-in example

The following code snippet illustrates how a light plug-in is called by the HWRM server:

+#include "HWRMpluginService.h" + +_LIT8( KHWRMLightApiEComMatch, "HWRMLight" ); + +iPlugin = CHWRMPluginService::NewL( KHWRMLightApiEComMatch, this ); +iTransCounter = 0; +. . . +HWRMLightCommand::TLightsOnData pluginCommand; +pluginCommand.iTarget = 0x00000001; // Set target to primary display +pluginCommand.iIntensity = 50; +pluginCommand.iFadeIn = EFalse; +HWRMLightCommand::TLightsOnCmdPackage pckg( pluginCommand ); +iPlugin->ProcessCommandL( HWRMLightCommand::ELightsOnCmdId, iTransCounter++, pckg ); + +//Example of how ProcessResponseL() or EventL() might be handled + +HWRMLightCommand::TErrorCodeResponsePackage errPckg; +errPckg.Copy( aData ); +TInt pluginErr = errPckg(); + +// Handle error here \ No newline at end of file