diff options
| -rw-r--r-- | Documentation/devicetree/bindings/dma/fsl-imx-dma.txt | 48 | ||||
| -rw-r--r-- | drivers/dma/imx-dma.c | 75 | ||||
| -rw-r--r-- | include/linux/platform_data/dma-imx.h | 6 |
3 files changed, 125 insertions, 4 deletions
diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt new file mode 100644 index 000000000000..2717ecb47db9 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt @@ -0,0 +1,48 @@ +* Freescale Direct Memory Access (DMA) Controller for i.MX + +This document will only describe differences to the generic DMA Controller and +DMA request bindings as described in dma/dma.txt . + +* DMA controller + +Required properties: +- compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27 +- reg : Should contain DMA registers location and length +- interrupts : First item should be DMA interrupt, second one is optional and + should contain DMA Error interrupt +- #dma-cells : Has to be 1. imx-dma does not support anything else. + +Optional properties: +- #dma-channels : Number of DMA channels supported. Should be 16. +- #dma-requests : Number of DMA requests supported. + +Example: + + dma: dma@10001000 { + compatible = "fsl,imx27-dma"; + reg = <0x10001000 0x1000>; + interrupts = <32 33>; + #dma-cells = <1>; + #dma-channels = <16>; + }; + + +* DMA client + +Clients have to specify the DMA requests with phandles in a list. + +Required properties: +- dmas: List of one or more DMA request specifiers. One DMA request specifier + consists of a phandle to the DMA controller followed by the integer + specifiying the request line. +- dma-names: List of string identifiers for the DMA requests. For the correct + names, have a look at the specific client driver. + +Example: + + sdhci1: sdhci@10013000 { + ... + dmas = <&dma 7>; + dma-names = "rx-tx"; + ... + }; diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c index f28583370d00..34c54cf08231 100644 --- a/drivers/dma/imx-dma.c +++ b/drivers/dma/imx-dma.c @@ -27,6 +27,8 @@ #include <linux/clk.h> #include <linux/dmaengine.h> #include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of_dma.h> #include <asm/irq.h> #include <linux/platform_data/dma-imx.h> @@ -186,6 +188,11 @@ struct imxdma_engine { enum imx_dma_type devtype; }; +struct imxdma_filter_data { + struct imxdma_engine *imxdma; + int request; +}; + static struct platform_device_id imx_dma_devtype[] = { { .name = "imx1-dma", @@ -202,6 +209,22 @@ static struct platform_device_id imx_dma_devtype[] = { }; MODULE_DEVICE_TABLE(platform, imx_dma_devtype); +static const struct of_device_id imx_dma_of_dev_id[] = { + { + .compatible = "fsl,imx1-dma", + .data = &imx_dma_devtype[IMX1_DMA], + }, { + .compatible = "fsl,imx21-dma", + .data = &imx_dma_devtype[IMX21_DMA], + }, { + .compatible = "fsl,imx27-dma", + .data = &imx_dma_devtype[IMX27_DMA], + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id); + static inline int is_imx1_dma(struct imxdma_engine *imxdma) { return imxdma->devtype == IMX1_DMA; @@ -996,13 +1019,50 @@ static void imxdma_issue_pending(struct dma_chan *chan) spin_unlock_irqrestore(&imxdma->lock, flags); } +static bool imxdma_filter_fn(struct dma_chan *chan, void *param) +{ + struct imxdma_filter_data *fdata = param; + struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan); + + if (chan->device->dev != fdata->imxdma->dev) + return false; + + imxdma_chan->dma_request = fdata->request; + chan->private = NULL; + + return true; +} + +static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + int count = dma_spec->args_count; + struct imxdma_engine *imxdma = ofdma->of_dma_data; + struct imxdma_filter_data fdata = { + .imxdma = imxdma, + }; + + if (count != 1) + return NULL; + + fdata.request = dma_spec->args[0]; + + return dma_request_channel(imxdma->dma_device.cap_mask, + imxdma_filter_fn, &fdata); +} + static int __init imxdma_probe(struct platform_device *pdev) { struct imxdma_engine *imxdma; struct resource *res; + const struct of_device_id *of_id; int ret, i; int irq, irq_err; + of_id = of_match_device(imx_dma_of_dev_id, &pdev->dev); + if (of_id) + pdev->id_entry = of_id->data; + imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL); if (!imxdma) return -ENOMEM; @@ -1136,8 +1196,19 @@ static int __init imxdma_probe(struct platform_device *pdev) goto err; } + if (pdev->dev.of_node) { + ret = of_dma_controller_register(pdev->dev.of_node, + imxdma_xlate, imxdma); + if (ret) { + dev_err(&pdev->dev, "unable to register of_dma_controller\n"); + goto err_of_dma_controller; + } + } + return 0; +err_of_dma_controller: + dma_async_device_unregister(&imxdma->dma_device); err: clk_disable_unprepare(imxdma->dma_ipg); clk_disable_unprepare(imxdma->dma_ahb); @@ -1150,6 +1221,9 @@ static int imxdma_remove(struct platform_device *pdev) dma_async_device_unregister(&imxdma->dma_device); + if (pdev->dev.of_node) + of_dma_controller_free(pdev->dev.of_node); + clk_disable_unprepare(imxdma->dma_ipg); clk_disable_unprepare(imxdma->dma_ahb); @@ -1159,6 +1233,7 @@ static int imxdma_remove(struct platform_device *pdev) static struct platform_driver imxdma_driver = { .driver = { .name = "imx-dma", + .of_match_table = imx_dma_of_dev_id, }, .id_table = imx_dma_devtype, .remove = imxdma_remove, diff --git a/include/linux/platform_data/dma-imx.h b/include/linux/platform_data/dma-imx.h index f6d30cc1cb77..beac6b8b6a7b 100644 --- a/include/linux/platform_data/dma-imx.h +++ b/include/linux/platform_data/dma-imx.h @@ -60,10 +60,8 @@ static inline int imx_dma_is_ipu(struct dma_chan *chan) static inline int imx_dma_is_general_purpose(struct dma_chan *chan) { - return strstr(dev_name(chan->device->dev), "sdma") || - !strcmp(dev_name(chan->device->dev), "imx1-dma") || - !strcmp(dev_name(chan->device->dev), "imx21-dma") || - !strcmp(dev_name(chan->device->dev), "imx27-dma"); + return !strcmp(chan->device->dev->driver->name, "imx-sdma") || + !strcmp(chan->device->dev->driver->name, "imx-dma"); } #endif |