/************************************************************************************ * arch/arm/src/stm32/stm32_dma.h * * Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ************************************************************************************/ #ifndef __ARCH_ARM_SRC_STM32_STM32_DMA_H #define __ARCH_ARM_SRC_STM32_STM32_DMA_H /************************************************************************************ * Included Files ************************************************************************************/ #include #include #include "chip.h" #if defined(CONFIG_STM32_STM32F10XX) # include "chip/stm32f10xxx_dma.h" #elif defined(CONFIG_STM32_STM32F40XX) # include "chip/stm32f40xxx_dma.h" #else # error "Unknown STM32 DMA" #endif /************************************************************************************ * Public Types ************************************************************************************/ typedef FAR void *DMA_HANDLE; typedef void (*dma_callback_t)(DMA_HANDLE handle, uint8_t isr, void *arg); #ifdef CONFIG_DEBUG_DMA #if defined(CONFIG_STM32_STM32F10XX) struct stm32_dmaregs_s { uint32_t isr; uint32_t ccr; uint32_t cndtr; uint32_t cpar; uint32_t cmar; }; #elif defined(CONFIG_STM32_STM32F40XX) struct stm32_dmaregs_s { uint32_t lisr; uint32_t hisr; uint32_t scr; uint32_t sndtr; uint32_t spar; uint32_t sm0ar; uint32_t sm1ar; uint32_t sfcr; }; #else # error "Unknown STM32 DMA" #endif #endif /************************************************************************************ * Public Data ************************************************************************************/ #ifndef __ASSEMBLY__ #undef EXTERN #if defined(__cplusplus) #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /************************************************************************************ * Public Functions ************************************************************************************/ /**************************************************************************** * Name: stm32_dmachannel * * Description: * Allocate a DMA channel. This function gives the caller mutually * exclusive access to the DMA channel specified by the 'chan' argument. * DMA channels are shared on the STM32: Devices sharing the same DMA * channel cannot do DMA concurrently! See the DMACHAN_* definitions in * stm32_dma.h. * * If the DMA channel is not available, then stm32_dmachannel() will wait * until the holder of the channel relinquishes the channel by calling * stm32_dmafree(). WARNING: If you have two devices sharing a DMA * channel and the code never releases the channel, the stm32_dmachannel * call for the other will hang forever in this function! Don't let your * design do that! * * Hmm.. I suppose this interface could be extended to make a non-blocking * version. Feel free to do that if that is what you need. * * Returned Value: * Provided that 'chan' is valid, this function ALWAYS returns a non-NULL, * void* DMA channel handle. (If 'chan' is invalid, the function will * assert if debug is enabled or do something ignorant otherwise). * * Assumptions: * - The caller does not hold he DMA channel. * - The caller can wait for the DMA channel to be freed if it is no * available. * ****************************************************************************/ EXTERN DMA_HANDLE stm32_dmachannel(int chan); /**************************************************************************** * Name: stm32_dmafree * * Description: * Release a DMA channel. If another thread is waiting for this DMA channel * in a call to stm32_dmachannel, then this function will re-assign the * DMA channel to that thread and wake it up. NOTE: The 'handle' used * in this argument must NEVER be used again until stm32_dmachannel() is * called again to re-gain access to the channel. * * Returned Value: * None * * Assumptions: * - The caller holds the DMA channel. * - There is no DMA in progress * ****************************************************************************/ EXTERN void stm32_dmafree(DMA_HANDLE handle); /**************************************************************************** * Name: stm32_dmasetup * * Description: * Configure DMA before using * ****************************************************************************/ EXTERN void stm32_dmasetup(DMA_HANDLE handle, uint32_t paddr, uint32_t maddr, size_t ntransfers, uint32_t ccr); /**************************************************************************** * Name: stm32_dmastart * * Description: * Start the DMA transfer * * Assumptions: * - DMA handle allocated by stm32_dmachannel() * - No DMA in progress * ****************************************************************************/ EXTERN void stm32_dmastart(DMA_HANDLE handle, dma_callback_t callback, void *arg, bool half); /**************************************************************************** * Name: stm32_dmastop * * Description: * Cancel the DMA. After stm32_dmastop() is called, the DMA channel is * reset and stm32_dmasetup() must be called before stm32_dmastart() can be * called again * * Assumptions: * - DMA handle allocated by stm32_dmachannel() * ****************************************************************************/ EXTERN void stm32_dmastop(DMA_HANDLE handle); /**************************************************************************** * Name: stm32_dmasample * * Description: * Sample DMA register contents * * Assumptions: * - DMA handle allocated by stm32_dmachannel() * ****************************************************************************/ #ifdef CONFIG_DEBUG_DMA EXTERN void stm32_dmasample(DMA_HANDLE handle, struct stm32_dmaregs_s *regs); #else # define stm32_dmasample(handle,regs) #endif /**************************************************************************** * Name: stm32_dmadump * * Description: * Dump previously sampled DMA register contents * * Assumptions: * - DMA handle allocated by stm32_dmachannel() * ****************************************************************************/ #ifdef CONFIG_DEBUG_DMA EXTERN void stm32_dmadump(DMA_HANDLE handle, const struct stm32_dmaregs_s *regs, const char *msg); #else # define stm32_dmadump(handle,regs,msg) #endif #undef EXTERN #if defined(__cplusplus) } #endif #endif /* __ASSEMBLY__ */ #endif /* __ARCH_ARM_SRC_STM32_STM32_DMA_H */