diff options
| -rw-r--r-- | Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt | 56 | ||||
| -rw-r--r-- | drivers/dma/imx-sdma.c | 40 |
2 files changed, 96 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt index d1e3f443e20..68cee4f5539 100644 --- a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt +++ b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt @@ -4,14 +4,70 @@ Required properties: - compatible : Should be "fsl,<chip>-sdma" - reg : Should contain SDMA registers location and length - interrupts : Should contain SDMA interrupt +- #dma-cells : Must be <3>. + The first cell specifies the DMA request/event ID. See details below + about the second and third cell. - fsl,sdma-ram-script-name : Should contain the full path of SDMA RAM scripts firmware +The second cell of dma phandle specifies the peripheral type of DMA transfer. +The full ID of peripheral types can be found below. + + ID transfer type + --------------------- + 0 MCU domain SSI + 1 Shared SSI + 2 MMC + 3 SDHC + 4 MCU domain UART + 5 Shared UART + 6 FIRI + 7 MCU domain CSPI + 8 Shared CSPI + 9 SIM + 10 ATA + 11 CCM + 12 External peripheral + 13 Memory Stick Host Controller + 14 Shared Memory Stick Host Controller + 15 DSP + 16 Memory + 17 FIFO type Memory + 18 SPDIF + 19 IPU Memory + 20 ASRC + 21 ESAI + +The third cell specifies the transfer priority as below. + + ID transfer priority + ------------------------- + 0 High + 1 Medium + 2 Low + Examples: sdma@83fb0000 { compatible = "fsl,imx51-sdma", "fsl,imx35-sdma"; reg = <0x83fb0000 0x4000>; interrupts = <6>; + #dma-cells = <3>; fsl,sdma-ram-script-name = "sdma-imx51.bin"; }; + +DMA clients connected to the i.MX SDMA controller must use the format +described in the dma.txt file. + +Examples: + +ssi2: ssi@70014000 { + compatible = "fsl,imx51-ssi", "fsl,imx21-ssi"; + reg = <0x70014000 0x4000>; + interrupts = <30>; + clocks = <&clks 49>; + dmas = <&sdma 24 1 0>, + <&sdma 25 1 0>; + dma-names = "rx", "tx"; + fsl,fifo-depth = <15>; +}; diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 092867bf795..1e44b8cf95d 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -36,6 +36,7 @@ #include <linux/dmaengine.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_dma.h> #include <asm/irq.h> #include <linux/platform_data/dma-imx-sdma.h> @@ -1296,6 +1297,35 @@ err_dma_alloc: return ret; } +static bool sdma_filter_fn(struct dma_chan *chan, void *fn_param) +{ + struct imx_dma_data *data = fn_param; + + if (!imx_dma_is_general_purpose(chan)) + return false; + + chan->private = data; + + return true; +} + +static struct dma_chan *sdma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct sdma_engine *sdma = ofdma->of_dma_data; + dma_cap_mask_t mask = sdma->dma_device.cap_mask; + struct imx_dma_data data; + + if (dma_spec->args_count != 3) + return NULL; + + data.dma_request = dma_spec->args[0]; + data.peripheral_type = dma_spec->args[1]; + data.priority = dma_spec->args[2]; + + return dma_request_channel(mask, sdma_filter_fn, &data); +} + static int __init sdma_probe(struct platform_device *pdev) { const struct of_device_id *of_id = @@ -1443,10 +1473,20 @@ static int __init sdma_probe(struct platform_device *pdev) goto err_init; } + if (np) { + ret = of_dma_controller_register(np, sdma_xlate, sdma); + if (ret) { + dev_err(&pdev->dev, "failed to register controller\n"); + goto err_register; + } + } + dev_info(sdma->dev, "initialized\n"); return 0; +err_register: + dma_async_device_unregister(&sdma->dma_device); err_init: kfree(sdma->script_addrs); err_alloc: |