On Fri, Aug 25, 2017 at 04:31:04PM +0200, Pierre-Yves MORDRET wrote: > +static int stm32_mdma_probe(struct platform_device *pdev) > +{ [snip] > + dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev) + sizeof(u32) * count, > + GFP_KERNEL); > + if (!dmadev) > + return -ENOMEM; > + > + dmadev->nr_channels = nr_channels; > + dmadev->nr_requests = nr_requests; > + device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks", > + dmadev->ahb_addr_masks, > + count); > + dmadev->nr_ahb_addr_masks = count; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + dmadev->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(dmadev->base)) > + return PTR_ERR(dmadev->base); > + > + dmadev->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(dmadev->clk)) { > + dev_err(&pdev->dev, "Error: Missing controller clock\n"); > + return PTR_ERR(dmadev->clk); > + } I am assuming if clk is not availble at this point of time you return clk error which maybe defer probe, right? > +static struct platform_driver stm32_mdma_driver = { > + .driver = { > + .name = "stm32-mdma", > + .of_match_table = stm32_mdma_of_match, > + }, > +}; > + > +static int __init stm32_mdma_init(void) > +{ > + return platform_driver_probe(&stm32_mdma_driver, stm32_mdma_probe); and you register platform_driver_probe() which per drivers/base/platform.c:760 is incompatible with defer probing. So this need a fix -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html