On 11/23/2017 06:48 AM, CK Hu wrote: > Hi, Matthias: > > On Tue, 2017-11-14 at 22:41 +0100, Matthias Brugger wrote: >> With the mtk-mmsys MFD device in place, we switch the probing for >> mt2701 from device-tree to mfd. >> >> Signed-off-by: Matthias Brugger <mbrugger@xxxxxxxx> >> --- >> drivers/gpu/drm/mediatek/mtk_drm_drv.c | 32 +++++++++++++++++++++++++------- >> 1 file changed, 25 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c >> index dd249cf5121e..5a263aa3ab6e 100644 >> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c >> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c >> @@ -21,6 +21,7 @@ >> #include <drm/drm_of.h> >> #include <linux/component.h> >> #include <linux/iommu.h> >> +#include <linux/mfd/mmsys.h> >> #include <linux/mfd/syscon.h> >> #include <linux/of_address.h> >> #include <linux/of_platform.h> >> @@ -392,9 +393,10 @@ static const struct of_device_id mtk_ddp_comp_dt_ids[] = { >> >> static int mtk_drm_probe(struct platform_device *pdev) >> { >> + struct mmsys_dev *mmsys_private; >> struct device *dev = &pdev->dev; >> struct mtk_drm_private *private; >> - struct device_node *node; >> + struct device_node *node, *parent_node; >> struct component_match *match = NULL; >> int ret; >> int i; >> @@ -407,12 +409,23 @@ static int mtk_drm_probe(struct platform_device *pdev) >> INIT_WORK(&private->commit.work, mtk_atomic_work); >> private->data = of_device_get_match_data(dev); >> >> - private->config_regs = syscon_node_to_regmap(dev->of_node); >> - if (IS_ERR(private->config_regs)) >> - return PTR_ERR(private->config_regs); >> + /* Check if called from mfd */ >> + if (!dev->of_node) { >> + mmsys_private = dev_get_drvdata(pdev->dev.parent); > > Why do you directly access parent's driver data? You just need the > device node of mmsys, maybe you could refer to [1]. > > [1] > https://elixir.free-electrons.com/linux/latest/source/drivers/reset/reset-berlin.c#L78 > The difference is, that the driver you mentioned gets probed via device tree matching, while we get invoked here through the id_table. So there is no device node (the if actually checkes for pdev->dev.of_node to identify exactly this case). Regards, Matthias _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel