irqchip/mbigen: Handle multiple device nodes in a mbigen module

Each mbigen device is represented as a independent platform device. If the
devices belong to the same mbigen hardware module, then the register space for
these devices is the same. That leads to a resource conflict.

The solution for this is to represent the mbigen module as a platform device
and make the mbigen devices subdevices of that. The register space is
associated to the mbigen module and therefor the resource conflict is avoided.

[ tglx: Massaged changelog, cleaned up the code and removed the silly printk ]

Signed-off-by: Ma Jun <majun258@huawei.com>
Cc: mark.rutland@arm.com
Cc: jason@lakedaemon.net
Cc: marc.zyngier@arm.com
Cc: Catalin.Marinas@arm.com
Cc: guohanjun@huawei.com
Cc: Will.Deacon@arm.com
Cc: huxinwei@huawei.com
Cc: lizefan@huawei.com
Cc: dingtianhong@huawei.com
Cc: zhaojunhua@hisilicon.com
Cc: liguozhu@hisilicon.com
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1458203641-17172-3-git-send-email-majun258@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 24 insertions, 14 deletions

diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
index 4dd3eb8a40b3..d67baa231c13 100644
--- a/drivers/irqchip/irq-mbigen.c
+++ b/drivers/irqchip/irq-mbigen.c
@@ -239,8 +239,11 @@ static struct irq_domain_ops mbigen_domain_ops = {
 static int mbigen_device_probe(struct platform_device *pdev)
 {
         struct mbigen_device *mgn_chip;
-        struct resource *res;
+        struct platform_device *child;
         struct irq_domain *domain;
+        struct device_node *np;
+        struct device *parent;
+        struct resource *res;
         u32 num_pins;
 
         mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
@@ -254,23 +257,30 @@ static int mbigen_device_probe(struct platform_device *pdev)
         if (IS_ERR(mgn_chip->base))
                 return PTR_ERR(mgn_chip->base);
 
-        if (of_property_read_u32(pdev->dev.of_node, "num-pins", &num_pins) < 0) {
-                dev_err(&pdev->dev, "No num-pins property\n");
-                return -EINVAL;
-        }
+        for_each_child_of_node(pdev->dev.of_node, np) {
+                if (!of_property_read_bool(np, "interrupt-controller"))
+                        continue;
 
-        domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
-                                                        mbigen_write_msg,
-                                                        &mbigen_domain_ops,
-                                                        mgn_chip);
+                parent = platform_bus_type.dev_root;
+                child = of_platform_device_create(np, NULL, parent);
+                if (IS_ERR(child))
+                        return PTR_ERR(child);
 
-        if (!domain)
-                return -ENOMEM;
+                if (of_property_read_u32(child->dev.of_node, "num-pins",
+                                         &num_pins) < 0) {
+                        dev_err(&pdev->dev, "No num-pins property\n");
+                        return -EINVAL;
+                }
+
+                domain = platform_msi_create_device_domain(&child->dev, num_pins,
+                                                           mbigen_write_msg,
+                                                           &mbigen_domain_ops,
+                                                           mgn_chip);
+                if (!domain)
+                        return -ENOMEM;
+        }
 
         platform_set_drvdata(pdev, mgn_chip);
-
-        dev_info(&pdev->dev, "Allocated %d MSIs\n", num_pins);
-
         return 0;
 }