On 07/22/2017 08:51 AM, Vinod Koul wrote:

On Thu, Jul 06, 2017 at 02:20:20PM +0200, Pierre-Yves MORDRET wrote:

quoted

+static int stm32_dmamux_probe(struct platform_device *pdev)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *dma_node;
+	struct stm32_dmamux_data *stm32_dmamux;
+	struct resource *res;
+	void __iomem *iomem;
+	int i, ret;
+
+	if (!node)
+		return -ENODEV;
+
+	stm32_dmamux = devm_kzalloc(&pdev->dev, sizeof(*stm32_dmamux),
+				    GFP_KERNEL);
+	if (!stm32_dmamux)
+		return -ENOMEM;
+
+	dma_node = of_parse_phandle(node, "dma-masters", 0);
+	if (!dma_node) {
+		dev_err(&pdev->dev, "Can't get DMA master node\n");
+		return -ENODEV;
+	}
+
+	if (device_property_read_u32(&pdev->dev, "dma-channels",
+				     &stm32_dmamux->dmamux_channels))
+		stm32_dmamux->dmamux_channels = STM32_DMAMUX_MAX_CHANNELS;
+
+	if (device_property_read_u32(&pdev->dev, "dma-requests",
+				     &stm32_dmamux->dmamux_requests))
+		stm32_dmamux->dmamux_requests = STM32_DMAMUX_MAX_REQUESTS;

I think defaults should be warned here too

ok

quoted

+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	iomem = devm_ioremap_resource(&pdev->dev, res);
+	if (!iomem)
+		return -ENOMEM;
+
+	spin_lock_init(&stm32_dmamux->lock);
+
+	stm32_dmamux->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(stm32_dmamux->clk)) {
+		dev_info(&pdev->dev, "Missing controller clock\n");

Can you check for EPROBE_DEFER and print only for if that is not the error
otherwise we end up sapmming with defered probe issues

This is what you meant ?
	if (IS_ERR(stm32_dmamux->clk) != EPROBE_DEFER) {
		dev_info(&pdev->dev, "Missing controller clock\n");
		return PTR_ERR(stm32_dmamux->clk);
	}

OR

	if (IS_ERR(stm32_dmamux->clk)) {
		if (IS_ERR(stm32_dmamux->clk) != EPROBE_DEFER)
			dev_info(&pdev->dev, "Missing controller clock\n");
		return PTR_ERR(stm32_dmamux->clk);
	}

quoted

+
+#ifndef __DMA_STM32_DMAMUX_H
+#define __DMA_STM32_DMAMUX_H
+
+#if defined(CONFIG_STM32_DMAMUX)
+int stm32_dmamux_set_config(struct device *dev, void *route_data, u32 chan_id);

Why do we need a custom API in this case?

This API is called by DMA when a slave is requested by client. DMA can work
without DMAMUX this API has been put in place to configure DMAMUX whether client
is requesting a DMAMUX Channel instead of a DMA one.

Thanks
Py