Hi, Jitao: On Tue, 2019-04-16 at 14:04 +0800, Jitao Shi 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. I think this patch just prevent delay, not to prevent dsi panel probe fail. In [1], you mention mipi_dsi_attach() is called in panel_simple_dsi_probe(), but panel_simple_dsi_probe() is trigger by mipi_dsi_host_register(), so the probe would success. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/panel/panel-simple.c?h=v5.0-rc6#n2987 > > So move the mipi_dsi_host_register to probe from bind. > > Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx> > --- > drivers/gpu/drm/mediatek/mtk_dsi.c | 50 ++++++++++++++++++------------ > 1 file changed, 30 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c > index b00eb2d2e086..6c4ac37f983d 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; Why do this? Regards, CK > + ret = mipi_dsi_host_register(&dsi->host); > + if (ret < 0) { > + dev_err(dev, "failed to register DSI host: %d\n", ret); > + 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);