自学教程：C++ DMA_CCR函数代码示例

void dma_channel_reset(uint32_t dma, uint8_t channel){	/* Disable channel and reset config bits. */	DMA_CCR(dma, channel) = 0;	/* Reset data transfer number. */	DMA_CNDTR(dma, channel) = 0;	/* Reset peripheral address. */	DMA_CPAR(dma, channel) = 0;	/* Reset memory address. */	DMA_CMAR(dma, channel) = 0;	/* Reset interrupt flags. */	DMA_IFCR(dma) |= DMA_IFCR_CIF(channel);}

void dma_set_read_from_peripheral(u32 dma, u8 channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_DIR;}

void dma_set_peripheral_address(uint32_t dma, uint8_t channel, uint32_t address){	if (!(DMA_CCR(dma, channel) & DMA_CCR_EN)) {		DMA_CPAR(dma, channel) = (uint32_t) address;	}}

void dma_enable_channel(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) |= DMA_CCR_EN;}

void dma_disable_half_transfer_interrupt(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_HTIE;}

void dma_set_read_from_memory(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) |= DMA_CCR_DIR;}

void dma_enable_circular_mode(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) |= DMA_CCR_CIRC;	DMA_CCR(dma, channel) &= ~DMA_CCR_MEM2MEM;}

void dma_disable_memory_increment_mode(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_MINC;}

void dma_enable_channel(u32 dma, u8 channel){	DMA_CCR(dma, channel) |= DMA_CCR_EN;}

void dma_disable_transfer_complete_interrupt(u32 dma, u8 channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_TCIE;}

void dma_disable_half_transfer_interrupt(u32 dma, u8 channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_HTIE;}

void dma_enable_half_transfer_interrupt(u32 dma, u8 channel){	DMA_CCR(dma, channel) |= DMA_CCR_HTIE;}

void dma_disable_transfer_error_interrupt(u32 dma, u8 channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_TEIE;}

void dma_enable_transfer_error_interrupt(u32 dma, u8 channel){	DMA_CCR(dma, channel) |= DMA_CCR_TEIE;}

void dma_set_read_from_memory(u32 dma, u8 channel){	DMA_CCR(dma, channel) |= DMA_CCR_DIR;}

void dma_set_memory_size(uint32_t dma, uint8_t channel, uint32_t mem_size){	DMA_CCR(dma, channel) &= ~(DMA_CCR_MSIZE_MASK);	DMA_CCR(dma, channel) |= mem_size;}

void dma_set_peripheral_size(uint32_t dma, uint8_t channel,			     uint32_t peripheral_size){	DMA_CCR(dma, channel) &= ~(DMA_CCR_PSIZE_MASK);	DMA_CCR(dma, channel) |= peripheral_size;}

void dma_disable_channel(u32 dma, u8 channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_EN;}

void dma_disable_peripheral_increment_mode(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_PINC;}

void dma_set_peripheral_address(u32 dma, u8 channel, u32 address){	if (!(DMA_CCR(dma, channel) & DMA_CCR_EN))		DMA_CPAR(dma, channel) = (u32) address;}

void dma_set_read_from_peripheral(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_DIR;}

void dma_set_memory_address(u32 dma, u8 channel, u32 address){	if (!(DMA_CCR(dma, channel) & DMA_CCR_EN))		DMA_CMAR(dma, channel) = (u32) address;}

void dma_disable_transfer_error_interrupt(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_TEIE;}

static int __init mx1_camera_probe(struct platform_device *pdev){	struct mx1_camera_dev *pcdev;	struct resource *res;	struct pt_regs regs;	struct clk *clk;	void __iomem *base;	unsigned int irq;	int err = 0;	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);	irq = platform_get_irq(pdev, 0);	if (!res || (int)irq <= 0) {		err = -ENODEV;		goto exit;	}	clk = clk_get(&pdev->dev, "csi_clk");	if (IS_ERR(clk)) {		err = PTR_ERR(clk);		goto exit;	}	pcdev = kzalloc(sizeof(*pcdev), GFP_KERNEL);	if (!pcdev) {		dev_err(&pdev->dev, "Could not allocate pcdev/n");		err = -ENOMEM;		goto exit_put_clk;	}	pcdev->res = res;	pcdev->clk = clk;	pcdev->pdata = pdev->dev.platform_data;	if (pcdev->pdata)		pcdev->mclk = pcdev->pdata->mclk_10khz * 10000;	if (!pcdev->mclk) {		dev_warn(&pdev->dev,			 "mclk_10khz == 0! Please, fix your platform data. "			 "Using default 20MHz/n");		pcdev->mclk = 20000000;	}	INIT_LIST_HEAD(&pcdev->capture);	spin_lock_init(&pcdev->lock);	/*	 * Request the regions.	 */	if (!request_mem_region(res->start, resource_size(res), DRIVER_NAME)) {		err = -EBUSY;		goto exit_kfree;	}	base = ioremap(res->start, resource_size(res));	if (!base) {		err = -ENOMEM;		goto exit_release;	}	pcdev->irq = irq;	pcdev->base = base;	/* request dma */	pcdev->dma_chan = imx_dma_request_by_prio(DRIVER_NAME, DMA_PRIO_HIGH);	if (pcdev->dma_chan < 0) {		dev_err(&pdev->dev, "Can't request DMA for MX1 CSI/n");		err = -EBUSY;		goto exit_iounmap;	}	dev_dbg(&pdev->dev, "got DMA channel %d/n", pcdev->dma_chan);	imx_dma_setup_handlers(pcdev->dma_chan, mx1_camera_dma_irq, NULL,			       pcdev);	imx_dma_config_channel(pcdev->dma_chan, IMX_DMA_TYPE_FIFO,			       IMX_DMA_MEMSIZE_32, DMA_REQ_CSI_R, 0);	/* burst length : 16 words = 64 bytes */	imx_dma_config_burstlen(pcdev->dma_chan, 0);	/* request irq */	err = claim_fiq(&fh);	if (err) {		dev_err(&pdev->dev, "Camera interrupt register failed /n");		goto exit_free_dma;	}	set_fiq_handler(&mx1_camera_sof_fiq_start, &mx1_camera_sof_fiq_end -						   &mx1_camera_sof_fiq_start);	regs.ARM_r8 = DMA_BASE + DMA_DIMR;	regs.ARM_r9 = DMA_BASE + DMA_CCR(pcdev->dma_chan);	regs.ARM_r10 = (long)pcdev->base + CSICR1;	regs.ARM_fp = (long)pcdev->base + CSISR;	regs.ARM_sp = 1 << pcdev->dma_chan;	set_fiq_regs(&regs);	mxc_set_irq_fiq(irq, 1);	enable_fiq(irq);//.........这里部分代码省略.........

void dma_disable_transfer_complete_interrupt(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_TCIE;}

void dma_enable_mem2mem_mode(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) |= DMA_CCR_MEM2MEM;	DMA_CCR(dma, channel) &= ~DMA_CCR_CIRC;}

void dma_disable_channel(uint32_t dma, uint8_t channel){	DMA_CCR(dma, channel) &= ~DMA_CCR_EN;}

void dma_set_priority(uint32_t dma, uint8_t channel, uint32_t prio){	DMA_CCR(dma, channel) &= ~(DMA_CCR_PL_MASK);	DMA_CCR(dma, channel) |= prio;}

void dma_set_memory_address(uint32_t dma, uint8_t channel, uint32_t address){	if (!(DMA_CCR(dma, channel) & DMA_CCR_EN)) {		DMA_CMAR(dma, channel) = (uint32_t) address;	}}

void dma_enable_circular_mode(u32 dma, u8 channel){	DMA_CCR(dma, channel) |= DMA_CCR_CIRC;	DMA_CCR(dma, channel) &= ~DMA_CCR_MEM2MEM;}