diff options
Diffstat (limited to 'drivers/dma/at_hdmac.c')
| -rw-r--r-- | drivers/dma/at_hdmac.c | 93 |
1 files changed, 87 insertions, 6 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 841546776159..3502c412caf9 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -24,6 +24,7 @@ #include <linux/slab.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_dma.h> #include "at_hdmac_regs.h" #include "dmaengine.h" @@ -676,7 +677,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, ctrlb |= ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR | ATC_FC_MEM2PER - | ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF); + | ATC_SIF(atchan->mem_if) | ATC_DIF(atchan->per_if); reg = sconfig->dst_addr; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; @@ -715,7 +716,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, ctrlb |= ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED | ATC_FC_PER2MEM - | ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF); + | ATC_SIF(atchan->per_if) | ATC_DIF(atchan->mem_if); reg = sconfig->src_addr; for_each_sg(sgl, sg, sg_len, i) { @@ -821,8 +822,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc, desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR | ATC_FC_MEM2PER - | ATC_SIF(AT_DMA_MEM_IF) - | ATC_DIF(AT_DMA_PER_IF); + | ATC_SIF(atchan->mem_if) + | ATC_DIF(atchan->per_if); break; case DMA_DEV_TO_MEM: @@ -832,8 +833,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc, desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED | ATC_FC_PER2MEM - | ATC_SIF(AT_DMA_PER_IF) - | ATC_DIF(AT_DMA_MEM_IF); + | ATC_SIF(atchan->per_if) + | ATC_DIF(atchan->mem_if); break; default: @@ -1189,6 +1190,67 @@ static void atc_free_chan_resources(struct dma_chan *chan) dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); } +#ifdef CONFIG_OF +static bool at_dma_filter(struct dma_chan *chan, void *slave) +{ + struct at_dma_slave *atslave = slave; + + if (atslave->dma_dev == chan->device->dev) { + chan->private = atslave; + return true; + } else { + return false; + } +} + +static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *of_dma) +{ + struct dma_chan *chan; + struct at_dma_chan *atchan; + struct at_dma_slave *atslave; + dma_cap_mask_t mask; + unsigned int per_id; + struct platform_device *dmac_pdev; + + if (dma_spec->args_count != 2) + return NULL; + + dmac_pdev = of_find_device_by_node(dma_spec->np); + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL); + if (!atslave) + return NULL; + /* + * We can fill both SRC_PER and DST_PER, one of these fields will be + * ignored depending on DMA transfer direction. + */ + per_id = dma_spec->args[1]; + atslave->cfg = ATC_FIFOCFG_HALFFIFO | ATC_DST_H2SEL_HW + | ATC_SRC_H2SEL_HW | ATC_DST_PER(per_id) + | ATC_SRC_PER(per_id); + atslave->dma_dev = &dmac_pdev->dev; + + chan = dma_request_channel(mask, at_dma_filter, atslave); + if (!chan) + return NULL; + + atchan = to_at_dma_chan(chan); + atchan->per_if = dma_spec->args[0] & 0xff; + atchan->mem_if = (dma_spec->args[0] >> 16) & 0xff; + + return chan; +} +#else +static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *of_dma) +{ + return NULL; +} +#endif /*-- Module Management -----------------------------------------------*/ @@ -1343,6 +1405,8 @@ static int __init at_dma_probe(struct platform_device *pdev) for (i = 0; i < plat_dat->nr_channels; i++) { struct at_dma_chan *atchan = &atdma->chan[i]; + atchan->mem_if = AT_DMA_MEM_IF; + atchan->per_if = AT_DMA_PER_IF; atchan->chan_common.device = &atdma->dma_common; dma_cookie_init(&atchan->chan_common); list_add_tail(&atchan->chan_common.device_node, @@ -1389,8 +1453,25 @@ static int __init at_dma_probe(struct platform_device *pdev) dma_async_device_register(&atdma->dma_common); + /* + * Do not return an error if the dmac node is not present in order to + * not break the existing way of requesting channel with + * dma_request_channel(). + */ + if (pdev->dev.of_node) { + err = of_dma_controller_register(pdev->dev.of_node, + at_dma_xlate, atdma); + if (err) { + dev_err(&pdev->dev, "could not register of_dma_controller\n"); + goto err_of_dma_controller_register; + } + } + return 0; +err_of_dma_controller_register: + dma_async_device_unregister(&atdma->dma_common); + dma_pool_destroy(atdma->dma_desc_pool); err_pool_create: platform_set_drvdata(pdev, NULL); free_irq(platform_get_irq(pdev, 0), atdma); |