3 files changed, 9 insertions, 4 deletions

diff --git a/drivers/irqchip/irq-versatile-fpga.c b/drivers/irqchip/irq-versatile-fpga.c
index 065b7a31a478..47a52ab580d8 100644
--- a/drivers/irqchip/irq-versatile-fpga.c
+++ b/drivers/irqchip/irq-versatile-fpga.c
@@ -119,7 +119,7 @@ static int fpga_irqdomain_map(struct irq_domain *d, unsigned int irq,
 
         /* Skip invalid IRQs, only register handlers for the real ones */
         if (!(f->valid & BIT(hwirq)))
-                return -ENOTSUPP;
+                return -EPERM;
         irq_set_chip_data(irq, f);
         irq_set_chip_and_handler(irq, &f->chip,
                                 handle_level_irq);
diff --git a/drivers/irqchip/irq-vic.c b/drivers/irqchip/irq-vic.c
index 884d11c7355f..2bbb00404cf5 100644
--- a/drivers/irqchip/irq-vic.c
+++ b/drivers/irqchip/irq-vic.c
@@ -197,7 +197,7 @@ static int vic_irqdomain_map(struct irq_domain *d, unsigned int irq,
 
         /* Skip invalid IRQs, only register handlers for the real ones */
         if (!(v->valid_sources & (1 << hwirq)))
-                return -ENOTSUPP;
+                return -EPERM;
         irq_set_chip_and_handler(irq, &vic_chip, handle_level_irq);
         irq_set_chip_data(irq, v->base);
         set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 5a83dde8ca0c..54a4d5223238 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -143,7 +143,10 @@ static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
  * irq_domain_add_simple() - Allocate and register a simple irq_domain.
  * @of_node: pointer to interrupt controller's device tree node.
  * @size: total number of irqs in mapping
- * @first_irq: first number of irq block assigned to the domain
+ * @first_irq: first number of irq block assigned to the domain,
+ *      pass zero to assign irqs on-the-fly. This will result in a
+ *      linear IRQ domain so it is important to use irq_create_mapping()
+ *      for each used IRQ, especially when SPARSE_IRQ is enabled.
  * @ops: map/unmap domain callbacks
  * @host_data: Controller private data pointer
  *
@@ -191,6 +194,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
         /* A linear domain is the default */
         return irq_domain_add_linear(of_node, size, ops, host_data);
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_simple);
 
 /**
  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
@@ -397,11 +401,12 @@ static void irq_domain_disassociate_many(struct irq_domain *domain,
         while (count--) {
                 int irq = irq_base + count;
                 struct irq_data *irq_data = irq_get_irq_data(irq);
-                irq_hw_number_t hwirq = irq_data->hwirq;
+                irq_hw_number_t hwirq;
 
                 if (WARN_ON(!irq_data || irq_data->domain != domain))
                         continue;
 
+                hwirq = irq_data->hwirq;
                 irq_set_status_flags(irq, IRQ_NOREQUEST);
 
                 /* remove chip and handler */