diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c index f12606aeff87c9..db5a4ef7607734 100644 --- a/drivers/dma/sf-pdma/sf-pdma.c +++ b/drivers/dma/sf-pdma/sf-pdma.c @@ -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); diff --git a/drivers/dma/sf-pdma/sf-pdma.h b/drivers/dma/sf-pdma/sf-pdma.h index 0c20167b097d0e..dcb3687bd5da26 100644 --- a/drivers/dma/sf-pdma/sf-pdma.h +++ b/drivers/dma/sf-pdma/sf-pdma.h @@ -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 */