[PATCH] mfd: Support dynamic allocation of IRQ range for wm831x

[Mark Brown <broonie@opensource.wolfsonmicro.com>]

Use irq_allocate_desc() to get the IRQ range, which turns into a noop on
non-sparse systems. Since all existing users are non-sparse there should
be no compatibility issues.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/mfd/wm831x-irq.c |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/wm831x-irq.c b/drivers/mfd/wm831x-irq.c
index b23d8d5..a25a7d5 100644
--- a/drivers/mfd/wm831x-irq.c
+++ b/drivers/mfd/wm831x-irq.c
@@ -527,9 +527,18 @@ int wm831x_irq_init(struct wm831x *wm831x, int irq)
 				 0xffff);
 	}
 
-	if (!pdata || !pdata->irq_base) {
-		dev_err(wm831x->dev,
-			"No interrupt base specified, no interrupts\n");
+	/* Try to dynamically allocate IRQs if no base is specified */
+	if (!pdata || !pdata->irq_base)
+		wm831x->irq_base = -1;
+	else
+		wm831x->irq_base = pdata->irq_base;
+
+	wm831x->irq_base = irq_alloc_descs(wm831x->irq_base, 0,
+					   WM831X_NUM_IRQS, 0);
+	if (wm831x->irq_base < 0) {
+		dev_warn(wm831x->dev, "Failed to allocate IRQs: %d\n",
+			 wm831x->irq_base);
+		wm831x->irq_base = 0;
 		return 0;
 	}
 
-- 
1.7.5.3