[PATCH v2 6/9] arm: twr-k70f120m: extend Freescale eDMA driver with the ability to support Kinetis SoC

From: Paul Osmialowski
Date: Tue Jun 30 2015 - 08:33:45 EST


Surprisingly small amount of work was required in order to extend already
existing eDMA driver with the support for Kinetis SoC architecture.

Signed-off-by: Paul Osmialowski <pawelo@xxxxxxxxxxx>
---
Documentation/devicetree/bindings/dma/fsl-edma.txt | 38 ++++++-
drivers/dma/fsl-edma.c | 114 ++++++++++++++++-----
2 files changed, 125 insertions(+), 27 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/fsl-edma.txt b/Documentation/devicetree/bindings/dma/fsl-edma.txt
index 191d7bd..88c3e20 100644
--- a/Documentation/devicetree/bindings/dma/fsl-edma.txt
+++ b/Documentation/devicetree/bindings/dma/fsl-edma.txt
@@ -9,6 +9,7 @@ group, DMAMUX0 or DMAMUX1, but not both.
Required properties:
- compatible :
- "fsl,vf610-edma" for eDMA used similar to that on Vybrid vf610 SoC
+ - "fsl,kinetis-edma" for eDMA used similar to that on Kinetis SoC
- reg : Specifies base physical address(s) and size of the eDMA registers.
The 1st region is eDMA control register's address and size.
The 2nd and the 3rd regions are programmable channel multiplexing
@@ -16,7 +17,8 @@ Required properties:
- interrupts : A list of interrupt-specifiers, one for each entry in
interrupt-names.
- interrupt-names : Should contain:
- "edma-tx" - the transmission interrupt
+ "edma-tx" - the transmission interrupt (Vybrid)
+ "edma-tx-n,m" - interrupt for channels n (0-15) and m (16-31) (Kinetis)
"edma-err" - the error interrupt
- #dma-cells : Must be <2>.
The 1st cell specifies the DMAMUX(0 for DMAMUX0 and 1 for DMAMUX1).
@@ -28,6 +30,7 @@ Required properties:
- clock-names : A list of channel group clock names. Should contain:
"dmamux0" - clock name of mux0 group
"dmamux1" - clock name of mux1 group
+ "edma" - clock gate for whole controller (Kinetis only)
- clocks : A list of phandle and clock-specifier pairs, one for each entry in
clock-names.

@@ -54,6 +57,39 @@ edma0: dma-controller@40018000 {
<&clks VF610_CLK_DMAMUX1>;
};

+edma: dma-controller@40008000 {
+ compatible = "fsl,kinetis-edma";
+ reg = <0x40008000 0x2000>, /* DMAC */
+ <0x40021000 0x1000>, /* DMAMUX0 */
+ <0x40022000 0x1000>; /* DMAMUX1 */
+ #dma-cells = <2>;
+ dma-channels = <32>;
+ interrupts = <0>, <1>, <2>, <3>,
+ <4>, <5>, <6>, <7>,
+ <8>, <9>, <10>, <11>,
+ <12>, <13>, <14>, <15>,
+ <16>;
+ interrupt-names = "edma-tx-0,16",
+ "edma-tx-1,17",
+ "edma-tx-2,18",
+ "edma-tx-3,19",
+ "edma-tx-4,20",
+ "edma-tx-5,21",
+ "edma-tx-6,22",
+ "edma-tx-7,23",
+ "edma-tx-8,24",
+ "edma-tx-9,25",
+ "edma-tx-10,26",
+ "edma-tx-11,27",
+ "edma-tx-12,28",
+ "edma-tx-13,29",
+ "edma-tx-14,30",
+ "edma-tx-15,31",
+ "edma-err";
+ clocks = <&mcg_cclk_gate 6 1>,
+ <&mcg_pclk_gate 5 1>, <&mcg_pclk_gate 5 2>;
+ clock-names = "edma", "dmamux0", "dmamux1";
+};

* DMA clients
DMA client drivers that uses the DMA function must use the format described
diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
index 915eec3..e41a3b9 100644
--- a/drivers/dma/fsl-edma.c
+++ b/drivers/dma/fsl-edma.c
@@ -164,13 +164,13 @@ struct fsl_edma_desc {
struct fsl_edma_engine {
struct dma_device dma_dev;
void __iomem *membase;
+ struct clk *clk;
void __iomem *muxbase[DMAMUX_NR];
struct clk *muxclk[DMAMUX_NR];
struct mutex fsl_edma_mutex;
u32 n_chans;
- int txirq;
- int errirq;
bool big_endian;
+ bool kinetis;
struct fsl_edma_chan chans[];
};

@@ -788,42 +788,85 @@ static void fsl_edma_free_chan_resources(struct dma_chan *chan)
}

static int
-fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
+fsl_edma_irq_init(struct platform_device *pdev,
+ struct fsl_edma_engine *fsl_edma)
{
+ struct device_node *np = pdev->dev.of_node;
+ int irq, errirq;
int ret;

- fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
- if (fsl_edma->txirq < 0) {
- dev_err(&pdev->dev, "Can't get edma-tx irq.\n");
- return fsl_edma->txirq;
- }
-
- fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
- if (fsl_edma->errirq < 0) {
+ errirq = platform_get_irq_byname(pdev, "edma-err");
+ if (errirq < 0) {
dev_err(&pdev->dev, "Can't get edma-err irq.\n");
- return fsl_edma->errirq;
+ return irq;
}

- if (fsl_edma->txirq == fsl_edma->errirq) {
- ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
- fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
- if (ret) {
- dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
- return ret;
+ if (fsl_edma->kinetis) {
+ int i;
+ int irqs = of_irq_count(np);
+
+ if (irqs <= 1) {
+ dev_err(&pdev->dev, "Wrong eDMA irq count %d\n", irqs);
+ return -EINVAL;
}
- } else {
- ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
+
+ for (i = 0; i < (irqs - 1); i++) {
+ char irq_name[32];
+
+ sprintf(irq_name, "edma-tx-%d,%d", i, 16 + i);
+ irq = platform_get_irq_byname(pdev, irq_name);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Can't get %s irq.\n",
+ irq_name);
+ return irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq,
fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
- if (ret) {
- dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
- return ret;
+ if (ret) {
+ dev_err(&pdev->dev, "Can't register %s IRQ.\n",
+ irq_name);
+ return ret;
+ }
}

- ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
- fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
+ ret = devm_request_irq(&pdev->dev, errirq,
+ fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
if (ret) {
dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
- return ret;
+ return ret;
+ }
+ } else {
+ irq = platform_get_irq_byname(pdev, "edma-tx");
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Can't get edma-tx irq.\n");
+ return irq;
+ }
+
+ if (irq == errirq) {
+ ret = devm_request_irq(&pdev->dev, irq,
+ fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Can't register eDMA IRQ.\n");
+ return ret;
+ }
+ } else {
+ ret = devm_request_irq(&pdev->dev, irq,
+ fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Can't register eDMA tx IRQ.\n");
+ return ret;
+ }
+
+ ret = devm_request_irq(&pdev->dev, errirq,
+ fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Can't register eDMA err IRQ.\n");
+ return ret;
+ }
}
}

@@ -851,6 +894,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
return -ENOMEM;

fsl_edma->n_chans = chans;
+ fsl_edma->kinetis = of_device_is_compatible(np, "fsl,kinetis-edma");
mutex_init(&fsl_edma->fsl_edma_mutex);

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -858,6 +902,20 @@ static int fsl_edma_probe(struct platform_device *pdev)
if (IS_ERR(fsl_edma->membase))
return PTR_ERR(fsl_edma->membase);

+ if (fsl_edma->kinetis) {
+ fsl_edma->clk = devm_clk_get(&pdev->dev, "edma");
+ if (IS_ERR(fsl_edma->clk)) {
+ dev_err(&pdev->dev, "Missing EDMA clock.\n");
+ return PTR_ERR(fsl_edma->clk);
+ }
+
+ ret = clk_prepare_enable(fsl_edma->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "EDMA clk failed.\n");
+ return ret;
+ }
+ }
+
for (i = 0; i < DMAMUX_NR; i++) {
char clkname[32];

@@ -956,10 +1014,14 @@ static int fsl_edma_remove(struct platform_device *pdev)
for (i = 0; i < DMAMUX_NR; i++)
clk_disable_unprepare(fsl_edma->muxclk[i]);

+ if (fsl_edma->kinetis)
+ clk_disable_unprepare(fsl_edma->clk);
+
return 0;
}

static const struct of_device_id fsl_edma_dt_ids[] = {
+ { .compatible = "fsl,kinetis-edma", },
{ .compatible = "fsl,vf610-edma", },
{ /* sentinel */ }
};
--
2.3.6

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