On 3/10/2026 2:53 AM, Dmitry Baryshkov wrote:

On Mon, Mar 09, 2026 at 01:03:38AM +0530, Vijayanand Jitta wrote:

quoted

From: Charan Teja Kalla <redacted>

Change of_map_id() to take a pointer to struct of_phandle_args
instead of passing target device node and translated IDs separately.
Update all callers accordingly.

Subsequent patch will make use of the args_count field in
struct of_phandle_args.

Suggested-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Charan Teja Kalla <redacted>
Signed-off-by: Vijayanand Jitta <redacted>
---
 drivers/cdx/cdx_msi.c                    |  5 ++-
 drivers/iommu/of_iommu.c                 |  2 +-
 drivers/irqchip/irq-gic-its-msi-parent.c | 11 ++++--
 drivers/of/base.c                        | 63 ++++++++++++++++----------------
 drivers/of/irq.c                         |  8 +++-
 drivers/pci/controller/dwc/pci-imx6.c    | 16 ++++++--
 drivers/pci/controller/pcie-apple.c      |  5 ++-
 drivers/xen/grant-dma-ops.c              |  4 +-
 include/linux/of.h                       | 12 +++---
 9 files changed, 76 insertions(+), 50 deletions(-)

diff --git a/drivers/cdx/cdx_msi.c b/drivers/cdx/cdx_msi.c
index 63b3544ec997..03232b5ffbca 100644
--- a/drivers/cdx/cdx_msi.c
+++ b/drivers/cdx/cdx_msi.c

@@ -121,6 +121,7 @@ static int cdx_msi_prepare(struct irq_domain *msi_domain,
 			   struct device *dev,
 			   int nvec, msi_alloc_info_t *info)
 {
+	struct of_phandle_args msi_spec = { .np = NULL };

Why do you need to set it? Parse functions ignore passed args, don't
they?

The parse function does check arg->np on input — if it is non-NULL,
it is used to match only entries targeting that specific node.

Also, there is this existing path in drivers/pci/msi/irqdomain.c which
pre-sets the node and passes it as input to of_msi_xlate(), so the node
pointer is not ignored by the parse code:

u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
{
        struct device_node *of_node;
        u32 rid = pci_dev_id(pdev);

        pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);

        of_node = irq_domain_get_of_node(domain);
        rid = of_node ? of_msi_xlate(&pdev->dev, &of_node, rid) :
                        iort_msi_map_id(&pdev->dev, rid);

        return rid;
}

quoted

 	struct cdx_device *cdx_dev = to_cdx_device(dev);
 	struct device *parent = cdx_dev->cdx->dev;
 	struct msi_domain_info *msi_info;

@@ -128,11 +129,13 @@ static int cdx_msi_prepare(struct irq_domain *msi_domain,
 	int ret;
 
 	/* Retrieve device ID from requestor ID using parent device */
-	ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, NULL, &dev_id);
+	ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, &msi_spec);
 	if (ret) {
 		dev_err(dev, "of_map_id failed for MSI: %d\n", ret);
 		return ret;
 	}
+	of_node_put(msi_spec.np);
+	dev_id = msi_spec.args[0];
 
 #ifdef GENERIC_MSI_DOMAIN_OPS
 	/* Set the device Id to be passed to the GIC-ITS */

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index a511ecf21fcd..d255d0f58e8c 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c

@@ -48,7 +48,7 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
 	struct of_phandle_args iommu_spec = { .args_count = 1 };

.args_count = 1 should be set by of_map_iommu_id now (and dropped here).

Sure, will move it.

quoted

 	int err;
 
-	err = of_map_iommu_id(master_np, *id, &iommu_spec.np, iommu_spec.args);
+	err = of_map_iommu_id(master_np, *id, &iommu_spec);
 	if (err)
 		return err;
 

diff --git a/drivers/irqchip/irq-gic-its-msi-parent.c b/drivers/irqchip/irq-gic-its-msi-parent.c
index b63343a227a9..729fa2f9f758 100644
--- a/drivers/irqchip/irq-gic-its-msi-parent.c
+++ b/drivers/irqchip/irq-gic-its-msi-parent.c

@@ -152,6 +152,8 @@ static int its_v5_pci_msi_prepare(struct irq_domain *domain, struct device *dev,
 static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u32 *dev_id,
 				phys_addr_t *pa)
 {
+	struct device_node *msi_ctrl __free(device_node) = NULL;
+	struct of_phandle_args msi_spec = { .np = NULL };
 	struct of_phandle_iterator it;
 	int ret;
 

@@ -178,9 +180,12 @@ static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u
 		}
 	}
 
-	struct device_node *msi_ctrl __free(device_node) = NULL;
-
-	return of_map_msi_id(dev->of_node, dev->id, &msi_ctrl, dev_id);
+	ret = of_map_msi_id(dev->of_node, dev->id, &msi_spec);
+	if (!ret) {
+		msi_ctrl = msi_spec.np;
+		*dev_id = msi_spec.args[0];
+	}
+	return ret;
 }
 
 static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 959305a84748..b6e07c5fe715 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c

@@ -2102,36 +2102,37 @@ int of_find_last_cache_level(unsigned int cpu)
  * @id: device ID to map.
  * @map_name: property name of the map to use.
  * @map_mask_name: optional property name of the mask to use.
- * @target: optional pointer to a target device node.
- * @id_out: optional pointer to receive the translated ID.
+ * @arg: pointer to a &struct of_phandle_args. On input, @arg->np may be
+ *	set to a target device node to match, or NULL to match any. On
+ *	success, @arg->np will be set to the matched target node (with a
+ *	reference held) and @arg->args[0] will contain the translated ID.

Is this part being actually used (and useful)?

Please refer the above comment. I see there is existing path in
drivers/pci/msi/irqdomain.c which sets np.

Thanks,
Vijay

quoted

  *
  * Given a device ID, look up the appropriate implementation-defined
  * platform ID and/or the target device which receives transactions on that
- * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
- * @id_out may be NULL if only the other is required. If @target points to
- * a non-NULL device node pointer, only entries targeting that node will be
- * matched; if it points to a NULL value, it will receive the device node of
- * the first matching target phandle, with a reference held.
+ * ID, as per the "iommu-map" and "msi-map" bindings. If @arg->np points to
+ * a non-NULL device node, only entries targeting that node will be matched;
+ * if it is NULL, it will receive the device node of the first matching
+ * target phandle, with a reference held.
  *
  * Return: 0 on success or a standard error code on failure.
  */
 int of_map_id(const struct device_node *np, u32 id,
 	       const char *map_name, const char *map_mask_name,
-	       struct device_node **target, u32 *id_out)
+	       struct of_phandle_args *arg)
 {
 	u32 map_mask, masked_id;
 	int map_len;
 	const __be32 *map = NULL;
 
-	if (!np || !map_name || (!target && !id_out))
+	if (!np || !map_name || !arg)
 		return -EINVAL;
 
 	map = of_get_property(np, map_name, &map_len);
 	if (!map) {
-		if (target)
+		if (arg->np)
 			return -ENODEV;
 		/* Otherwise, no map implies no translation */
-		*id_out = id;
+		arg->args[0] = id;
 		return 0;
 	}
 

@@ -2173,18 +2174,15 @@ int of_map_id(const struct device_node *np, u32 id,
 		if (!phandle_node)
 			return -ENODEV;
 
-		if (target) {
-			if (*target)
-				of_node_put(phandle_node);
-			else
-				*target = phandle_node;
+		if (arg->np)
+			of_node_put(phandle_node);
+		else
+			arg->np = phandle_node;
 
-			if (*target != phandle_node)
-				continue;
-		}
+		if (arg->np != phandle_node)
+			continue;
 
-		if (id_out)
-			*id_out = masked_id - id_base + out_base;
+		arg->args[0] = masked_id - id_base + out_base;
 
 		pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
 			np, map_name, map_mask, id_base, out_base,