From 7fbb75928749b74a0964ad159159066967191243 Mon Sep 17 00:00:00 2001 From: Dean Camera Date: Mon, 31 Aug 2009 07:48:32 +0000 Subject: Changed the parameters and behaviour of the USB_GetDeviceConfigDescriptor() function so that it now performs size checks and data validations internally, to simplify user code. --- .../KeyboardHostWithParser/ConfigDescriptor.c | 38 ++++++++++------------ 1 file changed, 17 insertions(+), 21 deletions(-) (limited to 'Demos/Host/LowLevel/KeyboardHostWithParser') diff --git a/Demos/Host/LowLevel/KeyboardHostWithParser/ConfigDescriptor.c b/Demos/Host/LowLevel/KeyboardHostWithParser/ConfigDescriptor.c index d9fd50f69..7ab0a1887 100644 --- a/Demos/Host/LowLevel/KeyboardHostWithParser/ConfigDescriptor.c +++ b/Demos/Host/LowLevel/KeyboardHostWithParser/ConfigDescriptor.c @@ -47,29 +47,25 @@ */ uint8_t ProcessConfigurationDescriptor(void) { - uint8_t* ConfigDescriptorData; - uint16_t ConfigDescriptorSize; - - /* Get Configuration Descriptor size from the device */ - if (USB_GetDeviceConfigDescriptor(1, &ConfigDescriptorSize, NULL) != HOST_SENDCONTROL_Successful) - return ControlError; - - /* Ensure that the Configuration Descriptor isn't too large */ - if (ConfigDescriptorSize > MAX_CONFIG_DESCRIPTOR_SIZE) - return DescriptorTooLarge; - - /* Allocate enough memory for the entire config descriptor */ - ConfigDescriptorData = alloca(ConfigDescriptorSize); + uint8_t ConfigDescriptorData[512]; + uint8_t* CurrConfigLocation = ConfigDescriptorData; + uint16_t CurrConfigBytesRem; /* Retrieve the entire configuration descriptor into the allocated buffer */ - USB_GetDeviceConfigDescriptor(1, &ConfigDescriptorSize, ConfigDescriptorData); - - /* Validate returned data - ensure first entry is a configuration header descriptor */ - if (DESCRIPTOR_TYPE(ConfigDescriptorData) != DTYPE_Configuration) - return InvalidConfigDataReturned; + switch (USB_GetDeviceConfigDescriptor(1, &CurrConfigBytesRem, ConfigDescriptorData, sizeof(ConfigDescriptorData))) + { + case HOST_GETCONFIG_Successful: + break; + case HOST_GETCONFIG_InvalidData: + return InvalidConfigDataReturned; + case HOST_GETCONFIG_BuffOverflow: + return DescriptorTooLarge; + default: + return ControlError; + } /* Get the keyboard interface from the configuration descriptor */ - if (USB_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, + if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation, DComp_NextKeyboardInterface) != DESCRIPTOR_SEARCH_COMP_Found) { /* Descriptor not found, error out */ @@ -77,7 +73,7 @@ uint8_t ProcessConfigurationDescriptor(void) } /* Get the keyboard interface's HID descriptor */ - if (USB_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, + if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation, DComp_NextHID) != DESCRIPTOR_SEARCH_COMP_Found) { /* Descriptor not found, error out */ @@ -88,7 +84,7 @@ uint8_t ProcessConfigurationDescriptor(void) HIDReportSize = DESCRIPTOR_CAST(ConfigDescriptorData, USB_Descriptor_HID_t).HIDReportLength; /* Get the keyboard interface's data endpoint descriptor */ - if (USB_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, + if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation, DComp_NextInterfaceKeyboardDataEndpoint) != DESCRIPTOR_SEARCH_COMP_Found) { /* Descriptor not found, error out */ -- cgit v1.2.3