| Message ID | 60f89b9a-f068-25a7-3f8b-d13b19357361@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 2017-05-12 at 17:05 +0200, Matthias Brugger wrote: > > On 12/05/17 05:22, Minghsiu Tsai wrote: > > From: Daniel Kurtz <djkurtz@chromium.org> > > > > 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.c > b/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 are aware of their out-of-date device tree blobs.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 Hi Matthias, It is a good idea to do compatible in such a way and put a warning the device tree is out of date.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 > > Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> > > 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; > >
On 15/05/17 04:31, Minghsiu Tsai wrote: > On Fri, 2017-05-12 at 17:05 +0200, Matthias Brugger wrote: >> >> On 12/05/17 05:22, Minghsiu Tsai wrote: >>> From: Daniel Kurtz <djkurtz@chromium.org> >>> >>> 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.c >> b/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. > Please integrate it into your patch series. Mauro, are you ok with the dev_warn about the out-of-date device-tree? Regards, Matthias > > Best Regards, > > Ming Hsiu > >>> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> >>> 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; >>> > >
diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c b/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;