On Tue, 11 Jun 2019 20:25:22 +0800 Qii Wang <qii.wang@xxxxxxxxxxxx> wrote: > On Tue, 2019-06-04 at 20:26 +0800, Qii Wang wrote: > > On Tue, 2019-06-04 at 09:58 +0200, Boris Brezillon wrote: > > > On Mon, 3 Jun 2019 11:51:03 +0800 > > > Qii Wang <qii.wang@xxxxxxxxxxxx> wrote: > > > > > > > > > > +static int mtk_i3c_master_probe(struct platform_device *pdev) > > > > +{ > > > > + struct device *dev = &pdev->dev; > > > > + struct mtk_i3c_master *master; > > > > + struct resource *res; > > > > + int ret, irqnr; > > > > + > > > > + master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL); > > > > + if (!master) > > > > + return -ENOMEM; > > > > + > > > > + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "main"); > > > > + master->regs = devm_ioremap_resource(dev, res); > > > > + if (IS_ERR(master->regs)) > > > > + return PTR_ERR(master->regs); > > > > + > > > > + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma"); > > > > + master->dma_regs = devm_ioremap_resource(dev, res); > > > > + if (IS_ERR(master->dma_regs)) > > > > + return PTR_ERR(master->dma_regs); > > > > + > > > > + irqnr = platform_get_irq(pdev, 0); > > > > + if (irqnr < 0) > > > > + return irqnr; > > > > + > > > > + ret = devm_request_irq(dev, irqnr, mtk_i3c_master_irq, > > > > + IRQF_TRIGGER_NONE, DRV_NAME, master); > > > > + if (ret < 0) { > > > > + dev_err(dev, "Request I3C IRQ %d fail\n", irqnr); > > > > + return ret; > > > > + } > > > > + > > > > + ret = of_property_read_u32(pdev->dev.of_node, "clock-div", > > > > + &master->clk_src_div); > > > > > > You say in one comment that this clock divider is fixed in HW but might > > > change on a per-SoC basis. If that's the case, you should get rid of > > > this clock-div prop and attach the divider to the compatible (using an > > > mtk_i3c_master_variant struct that contains a divider field). > > > > > > > ok, I will attach the divider to the compatible. > > > I have rechecked your comment, maybe I have misunderstood what you mean. > "clock-div" changes according to i2c source clock, different project may > change i2c source clock, The previous dt-binding may be misleading, I > will modify it. Is it fixed or configurable? Maybe it should be modeled as a clk driver. What's for sure is that we shouldn't have this divider defined in the DT.