Commit e2dfce24 authored by Zong Li's avatar Zong Li Committed by Vinod Koul
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dmaengine: sf-pdma: Get number of channel by device tree 



It currently assumes that there are always four channels, it would
cause the error if there is actually less than four channels. Change
that by getting number of channel from device tree.

For backwards-compatibility, it uses the default value (i.e. 4) when
there is no 'dma-channels' information in dts.

Signed-off-by: default avatarZong Li <zong.li@sifive.com>
Acked-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: default avatarBin Meng <bmeng.cn@gmail.com>
Link: https://lore.kernel.org/r/f08a95b6582a51712c5b2c3cb859136d07bfa8b9.1648461096.git.zong.li@sifive.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 06006ad2

drivers/dma/sf-pdma/sf-pdma.c

+16 −8
Original line number Diff line number Diff line
@@ -482,23 +482,30 @@ static void sf_pdma_setup_chans(struct sf_pdma *pdma) 
static int sf_pdma_probe(struct platform_device *pdev)

{

	struct sf_pdma *pdma;

	struct sf_pdma_chan *chan;

	struct resource *res;

	int len, chans;

	int ret;

	int ret, n_chans;

	const enum dma_slave_buswidth widths =

		DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |

		DMA_SLAVE_BUSWIDTH_4_BYTES | DMA_SLAVE_BUSWIDTH_8_BYTES |

		DMA_SLAVE_BUSWIDTH_16_BYTES | DMA_SLAVE_BUSWIDTH_32_BYTES |

		DMA_SLAVE_BUSWIDTH_64_BYTES;



	chans = PDMA_NR_CH;

	len = sizeof(*pdma) + sizeof(*chan) * chans;

	pdma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);

	ret = of_property_read_u32(pdev->dev.of_node, "dma-channels", &n_chans);

	if (ret) {

		/* backwards-compatibility for no dma-channels property */

		dev_dbg(&pdev->dev, "set number of channels to default value: 4\n");

		n_chans = PDMA_MAX_NR_CH;

	} else if (n_chans > PDMA_MAX_NR_CH) {

		dev_err(&pdev->dev, "the number of channels exceeds the maximum\n");

		return -EINVAL;

	}



	pdma = devm_kzalloc(&pdev->dev, struct_size(pdma, chans, n_chans),

			    GFP_KERNEL);

	if (!pdma)

		return -ENOMEM;



	pdma->n_chans = chans;

	pdma->n_chans = n_chans;



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	pdma->membase = devm_ioremap_resource(&pdev->dev, res);
@@ -556,7 +563,7 @@ static int sf_pdma_remove(struct platform_device *pdev) 
	struct sf_pdma_chan *ch;

	int i;



	for (i = 0; i < PDMA_NR_CH; i++) {

	for (i = 0; i < pdma->n_chans; i++) {

		ch = &pdma->chans[i];



		devm_free_irq(&pdev->dev, ch->txirq, ch);
@@ -574,6 +581,7 @@ static int sf_pdma_remove(struct platform_device *pdev) 


static const struct of_device_id sf_pdma_dt_ids[] = {

	{ .compatible = "sifive,fu540-c000-pdma" },

	{ .compatible = "sifive,pdma0" },

	{},

};

MODULE_DEVICE_TABLE(of, sf_pdma_dt_ids);

drivers/dma/sf-pdma/sf-pdma.h

+2 −6
Original line number Diff line number Diff line
@@ -22,11 +22,7 @@ 
#include "../dmaengine.h"

#include "../virt-dma.h"



#define PDMA_NR_CH					4



#if (PDMA_NR_CH != 4)

#error "Please define PDMA_NR_CH to 4"

#endif

#define PDMA_MAX_NR_CH					4



#define PDMA_BASE_ADDR					0x3000000

#define PDMA_CHAN_OFFSET				0x1000
@@ -118,7 +114,7 @@ struct sf_pdma { 
	void __iomem            *membase;

	void __iomem            *mappedbase;

	u32			n_chans;

	struct sf_pdma_chan	chans[PDMA_NR_CH];

	struct sf_pdma_chan	chans[];

};



#endif /* _SF_PDMA_H */