Hi Stefan, On Thu, Mar 05, 2015 at 12:10:20AM +0100, Stefan Agner wrote: > + > +static int vf610_nfc_probe_dt(struct device *dev, struct vf610_nfc_config *cfg) > +{ > + struct device_node *np = dev->of_node; > + int buswidth; > + u32 clkrate; > + > + if (!np) > + return 1; > + > + cfg->flash_bbt = of_get_nand_on_flash_bbt(np); > + > + if (!of_property_read_u32(np, "clock-frequency", &clkrate)) > + cfg->clkrate = clkrate; Normally the clock-frequency property tells the driver at which frequency the device actually is running, not to tell the driver at which frequency the device *should* run. It's strange to use the value of the clock-frequency property as input to clk_set_rate(). Maybe the assigned clock binding is more appropriate here, see Documentation/devicetree/bindings/clock/clock-bindings.txt. BTW the above can easier be written as: of_property_read_u32(np, "clock-frequency", &cfg->clkrate); No return value checking necessary. > +static int vf610_nfc_probe(struct platform_device *pdev) > +{ > + struct vf610_nfc *nfc; > + struct resource *res; > + struct mtd_info *mtd; > + struct nand_chip *chip; > + struct vf610_nfc_config *cfg; > + int err = 0; > + int page_sz; > + int irq; > + > + nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL); > + if (!nfc) > + return -ENOMEM; > + > + nfc->cfg = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL); > + if (!nfc->cfg) > + return -ENOMEM; > + cfg = nfc->cfg; Why is nfc->cfg allocated separately instead of embedding it into struct vf610_nfc? Is this some platform_data leftover you can remove now? > + > + nfc->dev = &pdev->dev; > + nfc->page = -1; > + mtd = &nfc->mtd; > + chip = &nfc->chip; > + > + mtd->priv = chip; > + mtd->owner = THIS_MODULE; > + mtd->dev.parent = nfc->dev; > + mtd->name = DRV_NAME; > + > + err = vf610_nfc_probe_dt(nfc->dev, cfg); > + if (err) > + return -ENODEV; Does this driver work without device tree or not? Currently the driver bails out when device tree support is enabled but no device node is given. When device tree support is disabled in the kernel though the driver happily continues here. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- 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