[tip: irq/core] genirq: Document interaction between <linux/irq.h> and DT binding defines

[tip-bot2 for Geert Uytterhoeven]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     5a8103a6fb0ae9cf99c0271b17474468d6bae2b2
Gitweb:        https://git.kernel.org/tip/5a8103a6fb0ae9cf99c0271b17474468d6bae2b2
Author:        Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
AuthorDate:    Wed, 04 Mar 2026 18:21:57 +01:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxx>
CommitterDate: Tue, 10 Mar 2026 18:37:21 +01:00

genirq: Document interaction between <linux/irq.h> and DT binding defines

Document that the DT binding definitions in
<dt-bindings/interrupt-controller/irq.h> shadow the first six IRQ_TYPE_*
definitions in <linux/irq.h>.  The values must be the same anyway, so this
is harmless (as long as the latter is included first when both are
included), but it is good to document this explicitly.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxx>
Link: https://patch.msgid.link/fbcc65dcee6c5437fab5ef18d21766bb4effb7cb.1772644406.git.geert+renesas@xxxxxxxxx
---
 include/linux/irq.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 951acbd..efa514e 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -35,6 +35,10 @@ enum irqchip_irq_state;
  *
  * Bits 0-7 are the same as the IRQF_* bits in linux/interrupt.h
  *
+ * Note that the first 6 definitions are shadowed by C preprocessor definitions
+ * in include/dt-bindings/interrupt-controller/irq.h.  This is not an issue, as
+ * the actual values must be the same, due to being part of the stable DT ABI.
+ *
  * IRQ_TYPE_NONE		- default, unspecified type
  * IRQ_TYPE_EDGE_RISING		- rising edge triggered
  * IRQ_TYPE_EDGE_FALLING	- falling edge triggered