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).
> + if (ret < 0)
> + return -EINVAL;
> +
> + spin_lock_init(&master->xferqueue.lock);
> + INIT_LIST_HEAD(&master->xferqueue.list);
> +
> + if (dma_set_mask(dev, DMA_BIT_MASK(33))) {
> + dev_err(dev, "dma_set_mask return error.\n");
> + return -EINVAL;
> + }
> +
> + master->clk_main = devm_clk_get(dev, "main");
> + if (IS_ERR(master->clk_main)) {
> + dev_err(dev, "cannot get main clock\n");
> + return PTR_ERR(master->clk_main);
> + }
> + master->clk_dma = devm_clk_get(dev, "dma");
> + if (IS_ERR(master->clk_dma)) {
> + dev_err(dev, "cannot get dma clock\n");
> + return PTR_ERR(master->clk_dma);
> + }
> +
> + master->clk_arb = devm_clk_get_optional(dev, "arb");
> + if (IS_ERR(master->clk_arb))
> + return PTR_ERR(master->clk_arb);
> +
> + ret = mtk_i3c_master_clock_enable(master);
> + if (ret) {
> + dev_err(dev, "clock enable failed!\n");
> + return ret;
> + }
> +
> + master->dev = dev;
> + platform_set_drvdata(pdev, master);
> +
> + ret = i3c_master_register(&master->mas_ctrler, dev,
> + &mtk_i3c_master_ops, false);
> + if (ret) {
> + dev_err(dev, "Failed to add i3c bus to i3c core\n");
> + mtk_i3c_master_clock_disable(master);
> + return ret;
> + }
> +
> + return 0;
> +}
