[PATCH v3 3/3] media: mtk-mdp: Fix mdp device tree
From: minghsiu.tsai@mediatek.com (Minghsiu Tsai)
Date: 2017-05-15 02:32:00
Also in:
linux-devicetree, linux-media, linux-mediatek, lkml
On Fri, 2017-05-12 at 17:05 +0200, Matthias Brugger wrote:
quoted hunk ↗ jump to hunk
On 12/05/17 05:22, Minghsiu Tsai wrote:quoted
From: Daniel Kurtz <redacted> If the mdp_* nodes are under an mdp sub-node, their corresponding platform device does not automatically get its iommu assigned properly. Fix this by moving the mdp component nodes up a level such that they are siblings of mdp and all other SoC subsystems. This also simplifies the device tree. Although it fixes iommu assignment issue, it also break compatibility with old device tree. So, the patch in driver is needed to iterate over sibling mdp device nodes, not child ones, to keep driver work properly.Couldn't we preserve backwards compatibility by doing something like this:diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_core.cb/drivers/media/platform/mtk-mdp/mtk_mdp_core.c index 9e4eb7dcc424..277d8fe6eb76 100644--- a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c +++ b/drivers/media/platform/mtk-mdp/mtk_mdp_core.c@@ -103,7 +103,7 @@ static int mtk_mdp_probe(struct platform_device *pdev) { struct mtk_mdp_dev *mdp; struct device *dev = &pdev->dev; - struct device_node *node; + struct device_node *node, *parent; int i, ret = 0; mdp = devm_kzalloc(dev, sizeof(*mdp), GFP_KERNEL);@@ -117,8 +117,14 @@ static int mtk_mdp_probe(struct platform_device *pdev) mutex_init(&mdp->lock); mutex_init(&mdp->vpulock); + /* Old dts had the components as child nodes */ + if (of_get_next_child(dev->of_node, NULL)) + parent = dev->of_node; + else + parent = dev->of_node->parent; + /* Iterate over sibling MDP function blocks */ - for_each_child_of_node(dev->of_node, node) { + for_each_child_of_node(parent, node) { const struct of_device_id *of_id; enum mtk_mdp_comp_type comp_type; int comp_id;Maybe even by putting a warning in the if branch to make sure, people are aware of their out-of-date device tree blobs. Regards, Matthias
Hi Matthias,
It is a good idea to do compatible in such a way and put a warning the
device tree is out of date. People can find out cause soon if device
tree is old.
I modify the code as below:
+ /* Old dts had the components as child nodes */
+ if (of_get_next_child(dev->of_node, NULL)) {
+ parent = dev->of_node;
+ dev_warn(dev, "device tree is out of date\n");
+ } else {
+ parent = dev->of_node->parent;
+ }
Will you upload it in a separate patch?
If not, I can merge it in my patch series and upload v4.
Best Regards,
Ming Hsiu
quoted
Signed-off-by: Daniel Kurtz <redacted> Signed-off-by: Minghsiu Tsai <minghsiu.tsai@mediatek.com> --- drivers/media/platform/mtk-mdp/mtk_mdp_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c b/drivers/media/platform/mtk-mdp/mtk_mdp_core.c index 9e4eb7d..a5ad586 100644 --- a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c +++ b/drivers/media/platform/mtk-mdp/mtk_mdp_core.c@@ -118,7 +118,7 @@ static int mtk_mdp_probe(struct platform_device *pdev) mutex_init(&mdp->vpulock); /* Iterate over sibling MDP function blocks */ - for_each_child_of_node(dev->of_node, node) { + for_each_child_of_node(dev->of_node->parent, node) { const struct of_device_id *of_id; enum mtk_mdp_comp_type comp_type; int comp_id;