irqchip: renesas-intc-irqpin: DT binding for sense bitfield width

Most Renesas irqpin controllers have 4-bit sense fields, however, some
have different widths. This patch adds a DT binding to optionally
specify such non-standard values.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

2 files changed, 18 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/interrupt-controller/renesas,intc-irqpin.txt b/Documentation/devicetree/bindings/interrupt-controller/renesas,intc-irqpin.txt
new file mode 100644
index 000000000000..66fcaf5b09ff
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/renesas,intc-irqpin.txt
@@ -0,0 +1,14 @@
+DT bindings for the R-/SH-Mobile irqpin controller
+
+Required properties:
+
+- compatible: has to be "renesas,intc-irqpin"
+- #interrupt-cells: has to be <2>: an interrupt index and flags, as defined in
+  interrupts.txt in this directory
+
+Optional properties:
+
+- any properties, listed in interrupts.txt, and any standard resource allocation
+  properties
+- sense-bitfield-width: width of a single sense bitfield in the SENSE register,
+  if different from the default 4 bits
diff --git a/drivers/irqchip/irq-renesas-intc-irqpin.c b/drivers/irqchip/irq-renesas-intc-irqpin.c
index 5a68e5accec1..4aca1b2bcc48 100644
--- a/drivers/irqchip/irq-renesas-intc-irqpin.c
+++ b/drivers/irqchip/irq-renesas-intc-irqpin.c
@@ -18,6 +18,7 @@
  */
 
 #include <linux/init.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
@@ -349,6 +350,9 @@ static int intc_irqpin_probe(struct platform_device *pdev)
         /* deal with driver instance configuration */
         if (pdata)
                 memcpy(&p->config, pdata, sizeof(*pdata));
+        else
+                of_property_read_u32(pdev->dev.of_node, "sense-bitfield-width",
+                                     &p->config.sense_bitfield_width);
         if (!p->config.sense_bitfield_width)
                 p->config.sense_bitfield_width = 4; /* default to 4 bits */