[PATCH v9 2/3] of: factor arguments passed to of_map_id() into a struct
Vijayanand Jitta
vijayanand.jitta at oss.qualcomm.com
Wed Mar 4 01:34:13 PST 2026
On 3/1/2026 3:32 PM, Dmitry Baryshkov wrote:
> On Sun, Mar 01, 2026 at 02:04:20PM +0530, Vijayanand Jitta wrote:
>> From: Charan Teja Kalla <charan.kalla at oss.qualcomm.com>
>>
>> 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 at kernel.org>
>> Signed-off-by: Charan Teja Kalla <charan.kalla at oss.qualcomm.com>
>> Signed-off-by: Vijayanand Jitta <vijayanand.jitta at oss.qualcomm.com>
>> ---
>> drivers/iommu/of_iommu.c | 2 +-
>> drivers/of/base.c | 37 +++++++++++++++++------------------
>> drivers/pci/controller/dwc/pci-imx6.c | 8 +++++++-
>> drivers/pci/controller/pcie-apple.c | 4 +++-
>> drivers/xen/grant-dma-ops.c | 2 +-
>> include/linux/of.h | 21 +++++++++++++-------
>> 6 files changed, 44 insertions(+), 30 deletions(-)
>>
>
>> @@ -2193,11 +2193,10 @@ int of_map_id(const struct device_node *np, u32 id,
>> }
>>
>> pr_info("%pOF: no %s translation for id 0x%x on %pOF\n", np, map_name,
>> - id, target && *target ? *target : NULL);
>> + id, arg->np ? arg->np : NULL);
>
> Is it just 'args->np' then? If it's NULL, it's NULL anyway.
>
Right, will update this.
>>
>> /* Bypasses translation */
>> - if (id_out)
>> - *id_out = id;
>> + arg->args[0] = id;
>> return 0;
>> }
>> EXPORT_SYMBOL_GPL(of_map_id);
>> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
>> index bff8289f804a..74fc603b3f84 100644
>> --- a/drivers/pci/controller/dwc/pci-imx6.c
>> +++ b/drivers/pci/controller/dwc/pci-imx6.c
>> @@ -1139,12 +1139,18 @@ static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
>> {
>> struct device *dev = imx_pcie->pci->dev;
>> struct device_node *target;
>> + struct of_phandle_args iommu_spec = { .args_count = 1 };
>> u32 sid_i, sid_m;
>> int err_i, err_m;
>> u32 sid = 0;
>>
>> target = NULL;
>> - err_i = of_map_iommu_id(dev->of_node, rid, &target, &sid_i);
>> + err_i = of_map_iommu_id(dev->of_node, rid, &iommu_spec);
>> + if (!err_i) {
>> + target = iommu_spec.np;
>> + sid_i = iommu_spec.args[0];
>> + }
>> +
>> if (target) {
>> of_node_put(target);
>> } else {
>> diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
>> index a0937b7b3c4d..e1d4b37d200d 100644
>> --- a/drivers/pci/controller/pcie-apple.c
>> +++ b/drivers/pci/controller/pcie-apple.c
>> @@ -755,6 +755,7 @@ static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_d
>> {
>> u32 sid, rid = pci_dev_id(pdev);
>> struct apple_pcie_port *port;
>> + struct of_phandle_args iommu_spec = { .args_count = 1 };
>> int idx, err;
>>
>> port = apple_pcie_get_port(pdev);
>> @@ -764,10 +765,11 @@ static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_d
>> dev_dbg(&pdev->dev, "added to bus %s, index %d\n",
>> pci_name(pdev->bus->self), port->idx);
>>
>> - err = of_map_iommu_id(port->pcie->dev->of_node, rid, NULL, &sid);
>> + err = of_map_iommu_id(port->pcie->dev->of_node, rid, &iommu_spec);
>> if (err)
>> return err;
>
> of_node_put(iommu_spec.np);
>
Sure, will add this.
>>
>> + sid = iommu_spec.args[0];
>> mutex_lock(&port->pcie->lock);
>>
>> idx = bitmap_find_free_region(port->sid_map, port->sid_map_sz, 0);
>> diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
>> index 1b7696b2d762..5f1d6540049a 100644
>> --- a/drivers/xen/grant-dma-ops.c
>> +++ b/drivers/xen/grant-dma-ops.c
>> @@ -325,7 +325,7 @@ static int xen_dt_grant_init_backend_domid(struct device *dev,
>> struct pci_dev *pdev = to_pci_dev(dev);
>> u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn);
>>
>> - if (of_map_iommu_id(np, rid, &iommu_spec.np, iommu_spec.args)) {
>> + if (of_map_iommu_id(np, rid, &iommu_spec)) {
>> dev_dbg(dev, "Cannot translate ID\n");
>> return -ESRCH;
>> }
>> diff --git a/include/linux/of.h b/include/linux/of.h
>> index 824649867810..9d72d76f909d 100644
>> --- a/include/linux/of.h
>> +++ b/include/linux/of.h
>> @@ -463,7 +463,7 @@ bool of_console_check(const struct device_node *dn, char *name, int index);
>>
>> 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);
>>
>> phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
>>
>> @@ -929,7 +929,7 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
>>
>> static inline 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)
>> {
>> return -EINVAL;
>> }
>> @@ -1458,17 +1458,24 @@ static inline int of_property_read_s32(const struct device_node *np,
>> }
>>
>> static inline int of_map_iommu_id(const struct device_node *np, u32 id,
>> - struct device_node **target, u32 *id_out)
>> + struct of_phandle_args *arg)
>
> Document that it's the caller's responsibility to of_node_put() returned
> node. As it can be seen from the previous comment, it's not obvious.
>
Sure, will add comment regarding this.
>> {
>> - return of_map_id(np, id, "iommu-map", "iommu-map-mask",
>> - target, id_out);
>> + return of_map_id(np, id, "iommu-map", "iommu-map-mask", arg);
>> }
>>
>> static inline int of_map_msi_id(const struct device_node *np, u32 id,
>> struct device_node **target, u32 *id_out)
>
> Is there a reason for chaning the of_map_iommu_id() args but not
> of_map_msi_id() args?
>
Thanks for pointing this out. I’ll update the series to keep of_map_iommu_id()
and of_map_msi_id() aligned.
>> {
>> - return of_map_id(np, id, "msi-map", "msi-map-mask",
>> - target, id_out);
>> + struct of_phandle_args msi_spec = { .np = *target, .args_count = 1 };
>
> Which driver passes something being worth of storing in .np?
>
You're right, There is no need to store these input args. Will remove these initializations.
Thanks,
Vijay
>> + int ret;
>> +
>> + ret = of_map_id(np, id, "msi-map", "msi-map-mask", &msi_spec);
>> + if (!ret) {
>> + *target = msi_spec.np;
>> + *id_out = msi_spec.args[0];
>> + }
>> +
>> + return ret;
>> }
>>
>> #define of_for_each_phandle(it, err, np, ln, cn, cc) \
>>
>> --
>> 2.34.1
>>
>
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