[PATCH 2/2] dma: imx-sdma: move to generic device tree bindings

[shawn.guo@linaro.org (Shawn Guo)]

Update imx-sdma driver to adopt generic DMA device tree bindings.  It
calls of_dma_controller_register() with imx-sdma specific of_dma_xlate
to get the generic DMA device tree helper support.  The #dma-cells for
imx-sdma must be 3, which includes request ID, peripheral type and
priority.

The definitions of peripheral type and priority get moved into
include/dt-bindings/dma/imx.h, so that the macros can also be used in
dts files.

The existing way of requesting channel, clients directly call
dma_request_channel(), still work there, and will be removed after
all imx-sdma clients get converted to generic DMA device tree helper.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 .../devicetree/bindings/dma/fsl-imx-sdma.txt       |   22 +++++++++++
 drivers/dma/imx-sdma.c                             |   40 ++++++++++++++++++++
 include/dt-bindings/dma/imx.h                      |   29 ++++++++++++++
 include/linux/platform_data/dma-imx.h              |   31 +--------------
 4 files changed, 92 insertions(+), 30 deletions(-)
 create mode 100644 include/dt-bindings/dma/imx.h

diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
index d1e3f44..053e20e 100644
--- a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
+++ b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
@@ -4,6 +4,11 @@ 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.  The second and
+  third cell specifies the peripheral type and priority of DMA transfer
+  respectively.  Refer to include/dt-bindings/dma/imx.h for available
+  peripheral types and priorities.
 - fsl,sdma-ram-script-name : Should contain the full path of SDMA RAM
   scripts firmware
 
@@ -13,5 +18,22 @@ sdma at 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 at 70014000 {
+	compatible = "fsl,imx51-ssi", "fsl,imx21-ssi";
+	reg = <0x70014000 0x4000>;
+	interrupts = <30>;
+	clocks = <&clks 49>;
+	dmas = <&sdma 24 DMA_PRIO_HIGH IMX_DMATYPE_SSI_SP>,
+	       <&sdma 25 DMA_PRIO_HIGH IMX_DMATYPE_SSI_SP>;
+	dma-names = "rx", "tx";
+	fsl,fifo-depth = <15>;
+};
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index e57a0c6..f1324da 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;
+}
+
+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:
diff --git a/include/dt-bindings/dma/imx.h b/include/dt-bindings/dma/imx.h
new file mode 100644
index 0000000..d5de68c
--- /dev/null
+++ b/include/dt-bindings/dma/imx.h
@@ -0,0 +1,29 @@
+/*
+ * This enumerates peripheral types. Used for SDMA.
+ */
+#define IMX_DMATYPE_SSI		0  /* MCU domain SSI */
+#define IMX_DMATYPE_SSI_SP	1  /* Shared SSI */
+#define IMX_DMATYPE_MMC		2  /* MMC */
+#define IMX_DMATYPE_SDHC	3  /* SDHC */
+#define IMX_DMATYPE_UART	4  /* MCU domain UART */
+#define IMX_DMATYPE_UART_SP	5  /* Shared UART */
+#define IMX_DMATYPE_FIRI	6  /* FIRI */
+#define IMX_DMATYPE_CSPI	7  /* MCU domain CSPI */
+#define IMX_DMATYPE_CSPI_SP	8  /* Shared CSPI */
+#define IMX_DMATYPE_SIM		9  /* SIM */
+#define IMX_DMATYPE_ATA		10 /* ATA */
+#define IMX_DMATYPE_CCM		11 /* CCM */
+#define IMX_DMATYPE_EXT		12 /* External peripheral */
+#define IMX_DMATYPE_MSHC	13 /* Memory Stick Host Controller */
+#define IMX_DMATYPE_MSHC_SP	14 /* Shared Memory Stick Host Controller */
+#define IMX_DMATYPE_DSP		15 /* DSP */
+#define IMX_DMATYPE_MEMORY	16 /* Memory */
+#define IMX_DMATYPE_FIFO_MEMORY	17 /* FIFO type Memory */
+#define IMX_DMATYPE_SPDIF	18 /* SPDIF */
+#define IMX_DMATYPE_IPU_MEMORY	19 /* IPU Memory */
+#define IMX_DMATYPE_ASRC	20 /* ASRC */
+#define IMX_DMATYPE_ESAI	21 /* ESAI */
+
+#define DMA_PRIO_HIGH		0
+#define DMA_PRIO_MEDIUM		1
+#define DMA_PRIO_LOW		2
diff --git a/include/linux/platform_data/dma-imx.h b/include/linux/platform_data/dma-imx.h
index 8a8a684..33f7eda 100644
--- a/include/linux/platform_data/dma-imx.h
+++ b/include/linux/platform_data/dma-imx.h
@@ -12,36 +12,7 @@
 #include <linux/scatterlist.h>
 #include <linux/device.h>
 #include <linux/dmaengine.h>
-
-/*
- * This enumerates peripheral types. Used for SDMA.
- */
-#define IMX_DMATYPE_SSI		0  /* MCU domain SSI */
-#define IMX_DMATYPE_SSI_SP	1  /* Shared SSI */
-#define IMX_DMATYPE_MMC		2  /* MMC */
-#define IMX_DMATYPE_SDHC	3  /* SDHC */
-#define IMX_DMATYPE_UART	4  /* MCU domain UART */
-#define IMX_DMATYPE_UART_SP	5  /* Shared UART */
-#define IMX_DMATYPE_FIRI	6  /* FIRI */
-#define IMX_DMATYPE_CSPI	7  /* MCU domain CSPI */
-#define IMX_DMATYPE_CSPI_SP	8  /* Shared CSPI */
-#define IMX_DMATYPE_SIM		9  /* SIM */
-#define IMX_DMATYPE_ATA		10 /* ATA */
-#define IMX_DMATYPE_CCM		11 /* CCM */
-#define IMX_DMATYPE_EXT		12 /* External peripheral */
-#define IMX_DMATYPE_MSHC	13 /* Memory Stick Host Controller */
-#define IMX_DMATYPE_MSHC_SP	14 /* Shared Memory Stick Host Controller */
-#define IMX_DMATYPE_DSP		15 /* DSP */
-#define IMX_DMATYPE_MEMORY	16 /* Memory */
-#define IMX_DMATYPE_FIFO_MEMORY	17 /* FIFO type Memory */
-#define IMX_DMATYPE_SPDIF	18 /* SPDIF */
-#define IMX_DMATYPE_IPU_MEMORY	19 /* IPU Memory */
-#define IMX_DMATYPE_ASRC	20 /* ASRC */
-#define IMX_DMATYPE_ESAI	21 /* ESAI */
-
-#define DMA_PRIO_HIGH		0
-#define DMA_PRIO_MEDIUM		1
-#define DMA_PRIO_LOW		2
+#include <dt-bindings/dma/imx.h>
 
 struct imx_dma_data {
 	int dma_request; /* DMA request line */
-- 
1.7.9.5