One more small comment, since you're respinning this: On Fri, Nov 06, 2015 at 11:48:08PM +0800, Bayi Cheng wrote: > diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c > new file mode 100644 > index 0000000..6582811 > --- /dev/null > +++ b/drivers/mtd/spi-nor/mtk-quadspi.c > @@ -0,0 +1,475 @@ ... > +static int mtk_nor_drv_probe(struct platform_device *pdev) > +{ > + struct device_node *flash_np; > + struct resource *res; > + int ret; > + struct mt8173_nor *mt8173_nor; > + > + if (!pdev->dev.of_node) { > + dev_err(&pdev->dev, "No DT found\n"); > + return -EINVAL; > + } > + > + mt8173_nor = devm_kzalloc(&pdev->dev, sizeof(*mt8173_nor), GFP_KERNEL); > + if (!mt8173_nor) > + return -ENOMEM; > + platform_set_drvdata(pdev, mt8173_nor); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(mt8173_nor->base)) > + return PTR_ERR(mt8173_nor->base); > + > + mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi"); > + if (IS_ERR(mt8173_nor->spi_clk)) { > + ret = PTR_ERR(mt8173_nor->spi_clk); > + goto nor_free; > + } > + > + mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf"); > + if (IS_ERR(mt8173_nor->nor_clk)) { > + ret = PTR_ERR(mt8173_nor->nor_clk); > + goto nor_free; > + } > + > + mt8173_nor->dev = &pdev->dev; > + clk_prepare_enable(mt8173_nor->spi_clk); > + clk_prepare_enable(mt8173_nor->nor_clk); You enable the clocks here, but... > + > + /* only support one attached flash */ > + flash_np = of_get_next_available_child(pdev->dev.of_node, NULL); > + if (!flash_np) { ... you might bail out here if there is no available flash node, and you never disable the clocks. (Same is true if we fail to detect the flash; you leave the no-longer-needed clocks enabled.) Seems like maybe you should disable clocks on failure. > + dev_err(&pdev->dev, "no SPI flash device to configure\n"); > + ret = -ENODEV; > + goto nor_free; > + } > + ret = mtk_nor_init(mt8173_nor, flash_np); > + > +nor_free: > + return ret; > +} Brian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html