[PATCH] pinctrl: sunxi: dt: number the IRQ banks from the first one that has IRQs

[Pablo Mazzini]

prepare_function_table() assumes the first pin is in bank 0. On the
A523, which has no PA pins, every IRQ bank is numbered one too high:
the last bank writes past the end of irq_array, and interrupts are
looked up at the wrong offsets.

Count the IRQ banks from the first bank that has interrupts.

Fixes: f5e2cd34b12f ("pinctrl: sunxi: allow reading mux values from DT")
Signed-off-by: Pablo Mazzini <pmazzini@xxxxxxxxx>
---
 drivers/pinctrl/sunxi/pinctrl-sunxi-dt.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi-dt.c b/drivers/pinctrl/sunxi/pinctrl-sunxi-dt.c
index 50a16f3bd131..9c5eb21a86a5 100644
--- a/drivers/pinctrl/sunxi/pinctrl-sunxi-dt.c
+++ b/drivers/pinctrl/sunxi/pinctrl-sunxi-dt.c
@@ -208,7 +208,7 @@ static int prepare_function_table(struct device *dev, struct device_node *pnode,
 	 * The extra functions will be filled in later.
 	 */
 	irq_bank = 0;
-	last_bank = 0;
+	last_bank = -1;
 	for (i = 0; i < npins; i++) {
 		struct sunxi_desc_pin *pin = &pins[i];
 		int bank = (pin->pin.number - pin_base) / PINS_PER_BANK;
@@ -221,16 +221,14 @@ static int prepare_function_table(struct device *dev, struct device_node *pnode,
 		func[1].muxval = 1;
 
 		if (irq_mux) {
-			if (bank > last_bank)
+			if (last_bank >= 0 && bank > last_bank)
 				irq_bank++;
 			func[lastfunc].muxval = irq_mux;
 			func[lastfunc].irqbank = irq_bank;
 			func[lastfunc].irqnum = pin->pin.number % PINS_PER_BANK;
 			func[lastfunc].name = "irq";
-		}
-
-		if (bank > last_bank)
 			last_bank = bank;
+		}
 
 		pin->functions = func;
 
-- 
2.53.0