Merge tag 'irq-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "The usual boring updates from the interrupt subsystem:

   - Infrastructure to allow building irqchip drivers as modules

   - Consolidation of irqchip ACPI probing

   - Removal of the EOI-preflow interrupt handler which was required for
     SPARC support and became obsolete after SPARC was converted to use
     sparse interrupts.

   - Cleanups, fixes and improvements all over the place"

* tag 'irq-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  irqchip/loongson-pch-pic: Fix the misused irq flow handler
  irqchip/loongson-htvec: Support 8 groups of HT vectors
  irqchip/loongson-liointc: Fix misuse of gc->mask_cache
  dt-bindings: interrupt-controller: Update Loongson HTVEC description
  irqchip/imx-intmux: Fix irqdata regs save in imx_intmux_runtime_suspend()
  irqchip/imx-intmux: Implement intmux runtime power management
  irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
  irqchip: Fix IRQCHIP_PLATFORM_DRIVER_* compilation by including module.h
  irqchip/stm32-exti: Map direct event to irq parent
  irqchip/mtk-cirq: Convert to a platform driver
  irqchip/mtk-sysirq: Convert to a platform driver
  irqchip/qcom-pdc: Switch to using IRQCHIP_PLATFORM_DRIVER helper macros
  irqchip: Add IRQCHIP_PLATFORM_DRIVER_BEGIN/END and IRQCHIP_MATCH helper macros
  irqchip: irq-bcm2836.h: drop a duplicated word
  irqchip/gic-v4.1: Ensure accessing the correct RD when writing INVALLR
  irqchip/irq-bcm7038-l1: Guard uses of cpu_logical_map
  irqchip/gic-v3: Remove unused register definition
  irqchip/qcom-pdc: Allow QCOM_PDC to be loadable as a permanent module
  genirq: Export irq_chip_retrigger_hierarchy and irq_chip_set_vcpu_affinity_parent
  irqdomain: Export irq_domain_update_bus_token
  ...

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/irqchip/irqchip.c b/drivers/irqchip/irqchip.c
index 2b35e68bea82..1bb0e36c2bf3 100644
--- a/drivers/irqchip/irqchip.c
+++ b/drivers/irqchip/irqchip.c
@@ -10,8 +10,10 @@
 
 #include <linux/acpi.h>
 #include <linux/init.h>
+#include <linux/of_device.h>
 #include <linux/of_irq.h>
 #include <linux/irqchip.h>
+#include <linux/platform_device.h>
 
 /*
  * This special of_device_id is the sentinel at the end of the
@@ -29,3 +31,30 @@ void __init irqchip_init(void)
 	of_irq_init(__irqchip_of_table);
 	acpi_probe_device_table(irqchip);
 }
+
+int platform_irqchip_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *par_np = of_irq_find_parent(np);
+	of_irq_init_cb_t irq_init_cb = of_device_get_match_data(&pdev->dev);
+
+	if (!irq_init_cb)
+		return -EINVAL;
+
+	if (par_np == np)
+		par_np = NULL;
+
+	/*
+	 * If there's a parent interrupt controller and  none of the parent irq
+	 * domains have been registered, that means the parent interrupt
+	 * controller has not been initialized yet.  it's not time for this
+	 * interrupt controller to initialize. So, defer probe of this
+	 * interrupt controller. The actual initialization callback of this
+	 * interrupt controller can check for specific domains as necessary.
+	 */
+	if (par_np && !irq_find_matching_host(np, DOMAIN_BUS_ANY))
+		return -EPROBE_DEFER;
+
+	return irq_init_cb(np, par_np);
+}
+EXPORT_SYMBOL_GPL(platform_irqchip_probe);