libopencm3
A free/libre/open-source firmware library for various ARM Cortex-M3 microcontrollers.
STM32F0
Here is a list of all modules:
[detail level 123]
 STM32F0xxLibraries for ST Microelectronics STM32F0xx series
 ADClibopencm3 STM32F0xx Analog to Digital Converters
 COMPlibopencm3 STM32F0xx COMP
 CRClibopencm3 STM32F0xx CRC
 DAClibopencm3 STM32F0xx DAC
 DMAlibopencm3 STM32F0xx DMA
 FLASHlibopencm3 STM32F05x FLASH
 GPIOlibopencm3 STM32F0xx General Purpose I/O
 I2Clibopencm3 STM32F0xx I2C
 IWDGlibopencm3 STM32F0xx Independent Watchdog Timer
 PWRlibopencm3 STM32F0xx Power Control
 RCClibopencm3 STM32F0xx Reset and Clock Control
 RTClibopencm3 STM32F0xx RTC
 SPIlibopencm3 STM32F0xx SPI
 SYSCFGlibopencm3 STM32F0xx SYSCFG
 Timerslibopencm3 STM32F0xx Timers
 USARTlibopencm3 STM32F0xx USART
 STM32F0xx DefinesDefined Constants and Types for the STM32F0xx series
 ADC DefinesDefined Constants and Types for the STM32F0xx Analog to Digital Converter
 CEC DefinesDefined Constants and Types for the STM32F0xx HDMI-CEC
 COMP Defineslibopencm3 Defined Constants and Types for the STM32F0xx Comparator module
 CRC Defineslibopencm3 Defined Constants and Types for the STM32F1xx CRC Generator
 DAC DefinesDefined Constants and Types for the STM32F0xx Digital to Analog Converter
 DMA DefinesDefined Constants and Types for the STM32F0xx DMA Controller
 EXTI DefinesDefined Constants and Types for the STM32F0xx External Interrupts
 FLASH DefinesDefined Constants and Types for the STM32F0xx Flash memory
 GPIO DefinesDefined Constants and Types for the STM32F0xx General Purpose I/O
 I2C DefinesDefined Constants and Types for the STM32F0xx I2C
 IWDG DefinesDefined Constants and Types for the STM32F0xx Independent Watchdog Timer
 PWR DefinesDefined Constants and Types for the STM32F0xx PWR Control
 RCC DefinesDefined Constants and Types for the STM32F0xx Reset and Clock Control
 RTC DefinesDefined Constants and Types for the STM32F0xx RTC
 SPI DefinesDefined Constants and Types for the STM32F0xx SPI
 SYSCFG DefinesDefined Constants and Types for the STM32F0xx System Config
 Timers DefinesDefined Constants and Types for the STM32F0xx Timers
 TSC DefinesDefined Constants and Types for the STM32F0xx Touch Sensor
 USART DefinesDefined Constants and Types for the STM32F0xx USART
 CRS DefinesSTM32 Clock Recovery System: Defined Constants and Types
 USB DefinesDefined Constants and Types for the STM32F* USB drivers
 CRSlibopencm3 STM32 Clock Recovery Subsystem