dmaengine: k3dma: Upgrade k3dma driver to support hisi_asp_dma hardware

On the hi3660 hardware there are two (at least) DMA controllers,
the DMA-P (Peripheral DMA) and the DMA-A (Audio DMA). The
two blocks are similar, but have some slight differences. This
resulted in the vendor implementing two separate drivers, which
after review, they have been able to condense and re-use the
existing k3dma driver.

Thus, this patch adds support for the new "hisi-pcm-asp-dma-1.0"
compatible string in the binding.

One difference with the DMA-A controller, is that it does not
need to initialize a clock. So we skip this by adding and using
soc data flags.

After above this driver will support both k3 and hisi_asp dma
hardware.

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Zhuangluan Su <suzhuangluan@hisilicon.com>
Cc: Ryan Grachek <ryan@edited.us>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: dmaengine@vger.kernel.org
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Youlin Wang <wwx575822@notesmail.huawei.com>
Signed-off-by: Tanglei Han <hantanglei@huawei.com>
[jstultz: Reworked to use of_match_data, commit msg improvements]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/k3dma.c

@@ -116,6 +116,14 @@ struct k3_dma_dev {
 	unsigned int		irq;
 };
 
+
+#define K3_FLAG_NOCLK	BIT(1)
+
+struct k3dma_soc_data {
+	unsigned long flags;
+};
+
+
 #define to_k3_dma(dmadev) container_of(dmadev, struct k3_dma_dev, slave)
 
 static int k3_dma_config_write(struct dma_chan *chan,
@@ -790,8 +798,21 @@ static int k3_dma_transfer_resume(struct dma_chan *chan)
 	return 0;
 }
 
+static const struct k3dma_soc_data k3_v1_dma_data = {
+	.flags = 0,
+};
+
+static const struct k3dma_soc_data asp_v1_dma_data = {
+	.flags = K3_FLAG_NOCLK,
+};
+
 static const struct of_device_id k3_pdma_dt_ids[] = {
-	{ .compatible = "hisilicon,k3-dma-1.0", },
+	{ .compatible = "hisilicon,k3-dma-1.0",
+	  .data = &k3_v1_dma_data
+	},
+	{ .compatible = "hisilicon,hisi-pcm-asp-dma-1.0",
+	  .data = &asp_v1_dma_data
+	},
 	{}
 };
 MODULE_DEVICE_TABLE(of, k3_pdma_dt_ids);
@@ -810,6 +831,7 @@ static struct dma_chan *k3_of_dma_simple_xlate(struct of_phandle_args *dma_spec,
 
 static int k3_dma_probe(struct platform_device *op)
 {
+	const struct k3dma_soc_data *soc_data;
 	struct k3_dma_dev *d;
 	const struct of_device_id *of_id;
 	struct resource *iores;
@@ -823,6 +845,10 @@ static int k3_dma_probe(struct platform_device *op)
 	if (!d)
 		return -ENOMEM;
 
+	soc_data = device_get_match_data(&op->dev);
+	if (!soc_data)
+		return -EINVAL;
+
 	d->base = devm_ioremap_resource(&op->dev, iores);
 	if (IS_ERR(d->base))
 		return PTR_ERR(d->base);
@@ -835,10 +861,12 @@ static int k3_dma_probe(struct platform_device *op)
 				"dma-requests", &d->dma_requests);
 	}
 
-	d->clk = devm_clk_get(&op->dev, NULL);
-	if (IS_ERR(d->clk)) {
-		dev_err(&op->dev, "no dma clk\n");
-		return PTR_ERR(d->clk);
+	if (!(soc_data->flags & K3_FLAG_NOCLK)) {
+		d->clk = devm_clk_get(&op->dev, NULL);
+		if (IS_ERR(d->clk)) {
+			dev_err(&op->dev, "no dma clk\n");
+			return PTR_ERR(d->clk);
+		}
 	}
 
 	irq = platform_get_irq(op, 0);