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. --- .../LowLevel/MassStorageHost/ConfigDescriptor.c | 38 ++++++++++------------ 1 file changed, 17 insertions(+), 21 deletions(-) (limited to 'Demos/Host/LowLevel/MassStorageHost/ConfigDescriptor.c') diff --git a/Demos/Host/LowLevel/MassStorageHost/ConfigDescriptor.c b/Demos/Host/LowLevel/MassStorageHost/ConfigDescriptor.c index 9f80b42ee..1ba3244ed 100644 --- a/Demos/Host/LowLevel/MassStorageHost/ConfigDescriptor.c +++ b/Demos/Host/LowLevel/MassStorageHost/ConfigDescriptor.c @@ -47,30 +47,26 @@ */ uint8_t ProcessConfigurationDescriptor(void) { - uint8_t* ConfigDescriptorData; - uint16_t ConfigDescriptorSize; - uint8_t FoundEndpoints = 0; - - /* 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; + uint8_t FoundEndpoints = 0; /* 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 mass storage interface from the configuration descriptor */ - if (USB_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, + if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation, DComp_NextMassStorageInterface) != DESCRIPTOR_SEARCH_COMP_Found) { /* Descriptor not found, error out */ @@ -81,7 +77,7 @@ uint8_t ProcessConfigurationDescriptor(void) while (FoundEndpoints != ((1 << MASS_STORE_DATA_IN_PIPE) | (1 << MASS_STORE_DATA_OUT_PIPE))) { /* Fetch the next bulk endpoint from the current mass storage interface */ - if (USB_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, + if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation, DComp_NextInterfaceBulkDataEndpoint) != DESCRIPTOR_SEARCH_COMP_Found) { /* Descriptor not found, error out */ -- cgit v1.2.3