diff options
Diffstat (limited to 'drivers/dma/mxs-dma.c')
| -rw-r--r-- | drivers/dma/mxs-dma.c | 70 |
1 files changed, 66 insertions, 4 deletions
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c index bb86f7ff55d9..b48a79c28845 100644 --- a/drivers/dma/mxs-dma.c +++ b/drivers/dma/mxs-dma.c @@ -27,6 +27,7 @@ #include <linux/stmp_device.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_dma.h> #include <asm/irq.h> @@ -139,6 +140,8 @@ struct mxs_dma_engine { struct dma_device dma_device; struct device_dma_parameters dma_parms; struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS]; + struct platform_device *pdev; + unsigned int nr_channels; }; struct mxs_dma_type { @@ -350,10 +353,8 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan) struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma; int ret; - if (!data) - return -EINVAL; - - mxs_chan->chan_irq = data->chan_irq; + if (data) + mxs_chan->chan_irq = data->chan_irq; mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, CCW_BLOCK_SIZE, &mxs_chan->ccw_phys, @@ -665,8 +666,55 @@ err_out: return ret; } +struct mxs_dma_filter_param { + struct device_node *of_node; + unsigned int chan_id; +}; + +static bool mxs_dma_filter_fn(struct dma_chan *chan, void *fn_param) +{ + struct mxs_dma_filter_param *param = fn_param; + struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan); + struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma; + int chan_irq; + + if (mxs_dma->dma_device.dev->of_node != param->of_node) + return false; + + if (chan->chan_id != param->chan_id) + return false; + + chan_irq = platform_get_irq(mxs_dma->pdev, param->chan_id); + if (chan_irq < 0) + return false; + + mxs_chan->chan_irq = chan_irq; + + return true; +} + +struct dma_chan *mxs_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct mxs_dma_engine *mxs_dma = ofdma->of_dma_data; + dma_cap_mask_t mask = mxs_dma->dma_device.cap_mask; + struct mxs_dma_filter_param param; + + if (dma_spec->args_count != 1) + return NULL; + + param.of_node = ofdma->of_node; + param.chan_id = dma_spec->args[0]; + + if (param.chan_id >= mxs_dma->nr_channels) + return NULL; + + return dma_request_channel(mask, mxs_dma_filter_fn, ¶m); +} + static int __init mxs_dma_probe(struct platform_device *pdev) { + struct device_node *np = pdev->dev.of_node; const struct platform_device_id *id_entry; const struct of_device_id *of_id; const struct mxs_dma_type *dma_type; @@ -678,6 +726,12 @@ static int __init mxs_dma_probe(struct platform_device *pdev) if (!mxs_dma) return -ENOMEM; + ret = of_property_read_u32(np, "dma-channels", &mxs_dma->nr_channels); + if (ret) { + dev_err(&pdev->dev, "failed to read dma-channels\n"); + return ret; + } + of_id = of_match_device(mxs_dma_dt_ids, &pdev->dev); if (of_id) id_entry = of_id->data; @@ -723,6 +777,7 @@ static int __init mxs_dma_probe(struct platform_device *pdev) if (ret) return ret; + mxs_dma->pdev = pdev; mxs_dma->dma_device.dev = &pdev->dev; /* mxs_dma gets 65535 bytes maximum sg size */ @@ -743,6 +798,13 @@ static int __init mxs_dma_probe(struct platform_device *pdev) return ret; } + ret = of_dma_controller_register(np, mxs_dma_xlate, mxs_dma); + if (ret) { + dev_err(mxs_dma->dma_device.dev, + "failed to register controller\n"); + dma_async_device_unregister(&mxs_dma->dma_device); + } + dev_info(mxs_dma->dma_device.dev, "initialized\n"); return 0; |