From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthias Brugger Subject: Re: [PATCH v3 3/3] media: mtk-mdp: Fix mdp device tree Date: Fri, 12 May 2017 17:05:27 +0200 Message-ID: <60f89b9a-f068-25a7-3f8b-d13b19357361@gmail.com> References: <1494559361-42835-1-git-send-email-minghsiu.tsai@mediatek.com> <1494559361-42835-4-git-send-email-minghsiu.tsai@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1494559361-42835-4-git-send-email-minghsiu.tsai-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org> Content-Language: en-US Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Minghsiu Tsai , Hans Verkuil , daniel.thompson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, Rob Herring , Mauro Carvalho Chehab , Daniel Kurtz , Pawel Osciak , Houlong Wei Cc: srv_heupstream-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, Eddie Huang , Yingjoe Chen , Wu-Cheng Li , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org On 12/05/17 05:22, Minghsiu Tsai wrote: > From: Daniel Kurtz > > 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 > Signed-off-by: Daniel Kurtz > Signed-off-by: Minghsiu Tsai > > --- > 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; > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html