[PATCH 3/8] drm/mediatek: mt2701: switch to mfd probing.

CK Hu
2017-11-23T05:48:12Z

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@suse.com>
> ---
> 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

Regards,
CK

> + private->data = (struct mtk_mmsys_driver_data *)
> + platform_get_device_id(pdev)->driver_data;
> + private->config_regs =
> + syscon_node_to_regmap(mmsys_private->of_node);
> + parent_node = mmsys_private->of_node->parent;
> + } else {
> + private->config_regs = syscon_node_to_regmap(dev->of_node);
> + if (IS_ERR(private->config_regs))
> + return PTR_ERR(private->config_regs);
> + parent_node = dev->of_node->parent;
> + }
>
> /* Iterate over sibling DISP function blocks */
> - for_each_child_of_node(dev->of_node->parent, node) {
> + for_each_child_of_node(parent_node, node) {
> const struct of_device_id *of_id;
> enum mtk_ddp_comp_type comp_type;
> int comp_id;
> @@ -553,13 +566,17 @@ static SIMPLE_DEV_PM_OPS(mtk_drm_pm_ops, mtk_drm_sys_suspend,
> mtk_drm_sys_resume);
>
> static const struct of_device_id mtk_drm_of_ids[] = {
> - { .compatible = "mediatek,mt2701-mmsys",
> - .data = &mt2701_mmsys_driver_data},
> { .compatible = "mediatek,mt8173-mmsys",
> .data = &mt8173_mmsys_driver_data},
> { }
> };
>
> +static const struct platform_device_id mtk_drm_ids[] = {
> + { "drm-mt2701-mm", (kernel_ulong_t)&mt2701_mmsys_driver_data },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(platform, mtk_drm_ids);
> +
> static struct platform_driver mtk_drm_platform_driver = {
> .probe = mtk_drm_probe,
> .remove = mtk_drm_remove,
> @@ -568,6 +585,7 @@ static struct platform_driver mtk_drm_platform_driver = {
> .of_match_table = mtk_drm_of_ids,
> .pm = &mtk_drm_pm_ops,
> },
> + .id_table = mtk_drm_ids,
> };
>
> static struct platform_driver * const mtk_drm_drivers[] = {