Re: [PATCH 1/3] drm/mediatek: move mipi_dsi_host_register to probe

Nicolas Boichat
2019-02-14T06:02:36Z

Just some comments on the error path, I'm not sure about the change itself.

On Thu, Feb 14, 2019 at 12:42 PM Jitao Shi <jitao.shi@mediatek.com> wrote:
>
> DSI panel driver need attach function which is inculde in
> mipi_dsi_host_ops.
>
> If mipi_dsi_host_register is not in probe, dsi panel will
> probe fail or more delay.
>
> So move the mipi_dsi_host_register to probe from bind.
>
> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_dsi.c | 49 ++++++++++++++++++------------
> 1 file changed, 30 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 27b507eb4a99..93fa255b4aad 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -1045,12 +1045,6 @@ static int mtk_dsi_bind(struct device *dev, struct device *master, void *data)
> return ret;
> }
>
> - ret = mipi_dsi_host_register(&dsi->host);
> - if (ret < 0) {
> - dev_err(dev, "failed to register DSI host: %d\n", ret);
> - goto err_ddp_comp_unregister;
> - }
> -
> ret = mtk_dsi_create_conn_enc(drm, dsi);
> if (ret) {
> DRM_ERROR("Encoder create failed with %d\n", ret);
> @@ -1060,8 +1054,6 @@ static int mtk_dsi_bind(struct device *dev, struct device *master, void *data)
> return 0;
>
> err_unregister:
> - mipi_dsi_host_unregister(&dsi->host);
> -err_ddp_comp_unregister:
> mtk_ddp_comp_unregister(drm, &dsi->ddp_comp);
> return ret;
> }
> @@ -1097,31 +1089,37 @@ static int mtk_dsi_probe(struct platform_device *pdev)
>
> dsi->host.ops = &mtk_dsi_ops;
> dsi->host.dev = dev;
> + dsi->dev = dev;
> + ret = mipi_dsi_host_register(&dsi->host);
> + if (ret < 0) {
> + dev_err(dev, "failed to register DSI host: %d\n", ret);
> + return -EPROBE_DEFER;

return ret

> + }
>
> ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0,
> &dsi->panel, &dsi->bridge);
> if (ret)
> - return ret;
> + goto err_unregister_host;
>
> dsi->engine_clk = devm_clk_get(dev, "engine");
> if (IS_ERR(dsi->engine_clk)) {
> ret = PTR_ERR(dsi->engine_clk);
> dev_err(dev, "Failed to get engine clock: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> dsi->digital_clk = devm_clk_get(dev, "digital");
> if (IS_ERR(dsi->digital_clk)) {
> ret = PTR_ERR(dsi->digital_clk);
> dev_err(dev, "Failed to get digital clock: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> dsi->hs_clk = devm_clk_get(dev, "hs");
> if (IS_ERR(dsi->hs_clk)) {
> ret = PTR_ERR(dsi->hs_clk);
> dev_err(dev, "Failed to get hs clock: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> @@ -1129,33 +1127,35 @@ static int mtk_dsi_probe(struct platform_device *pdev)
> if (IS_ERR(dsi->regs)) {
> ret = PTR_ERR(dsi->regs);
> dev_err(dev, "Failed to ioremap memory: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> dsi->phy = devm_phy_get(dev, "dphy");
> if (IS_ERR(dsi->phy)) {
> ret = PTR_ERR(dsi->phy);
> dev_err(dev, "Failed to get MIPI-DPHY: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DSI);
> if (comp_id < 0) {
> dev_err(dev, "Failed to identify by alias: %d\n", comp_id);
> - return comp_id;
> + ret = comp_id;
> + goto err_unregister_host;
> }
>
> ret = mtk_ddp_comp_init(dev, dev->of_node, &dsi->ddp_comp, comp_id,
> &mtk_dsi_funcs);
> if (ret) {
> dev_err(dev, "Failed to initialize component: %d\n", ret);
> - return ret;
> + goto err_unregister_host;
> }
>
> irq_num = platform_get_irq(pdev, 0);
> if (irq_num < 0) {
> dev_err(&pdev->dev, "failed to request dsi irq resource\n");
> - return -EPROBE_DEFER;
> + ret = -EPROBE_DEFER;

I think you need to do ret = irq_num here, too (and yes, it was
probably wrong before?)

> + goto err_unregister_host;
> }
>
> irq_set_status_flags(irq_num, IRQ_TYPE_LEVEL_LOW);
> @@ -1163,14 +1163,25 @@ static int mtk_dsi_probe(struct platform_device *pdev)
> IRQF_TRIGGER_LOW, dev_name(&pdev->dev), dsi);
> if (ret) {
> dev_err(&pdev->dev, "failed to request mediatek dsi irq\n");
> - return -EPROBE_DEFER;
> + ret = -EPROBE_DEFER;

Ditto, I'd not reassign ret.

> + goto err_unregister_host;
> }
>
> init_waitqueue_head(&dsi->irq_wait_queue);
>
> platform_set_drvdata(pdev, dsi);
>
> - return component_add(&pdev->dev, &mtk_dsi_component_ops);
> + ret = component_add(&pdev->dev, &mtk_dsi_component_ops);
> + if (ret) {
> + ret = -EPROBE_DEFER;

Ditto (this one _was_ right before).

> + goto err_unregister_host;
> + }
> +
> + return 0;
> +
> +err_unregister_host:
> + mipi_dsi_host_unregister(&dsi->host);
> + return ret;
> }
>
> static int mtk_dsi_remove(struct platform_device *pdev)
> --
> 2.20.1
>