pinctrl: sunxi: Always call chained_irq_{enter, exit} in sunxi_pinctrl_irq_handler

It is found on many allwinner soc that there is a low probability that
the interrupt status cannot be read in sunxi_pinctrl_irq_handler. This
will cause the interrupt status of a gpio bank to always be active on
gic, preventing gic from responding to other spi interrupts correctly.

So we should call the chained_irq_* each time enter sunxi_pinctrl_irq_handler().
Signed-off-by: Yangtao Li <frank@allwinnertech.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/85263ce8b058e80cea25c6ad6383eb256ce96cc8.1604988979.git.frank@allwinnertech.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/sunxi/pinctrl-sunxi.c

@@ -1141,20 +1141,22 @@ static void sunxi_pinctrl_irq_handler(struct irq_desc *desc)
 
 	WARN_ON(bank == pctl->desc->irq_banks);
 
+	chained_irq_enter(chip, desc);
+
 	reg = sunxi_irq_status_reg_from_bank(pctl->desc, bank);
 	val = readl(pctl->membase + reg);
 
 	if (val) {
 		int irqoffset;
 
-		chained_irq_enter(chip, desc);
 		for_each_set_bit(irqoffset, &val, IRQ_PER_BANK) {
 			int pin_irq = irq_find_mapping(pctl->domain,
 						       bank * IRQ_PER_BANK + irqoffset);
 			generic_handle_irq(pin_irq);
 		}
-		chained_irq_exit(chip, desc);
 	}
+
+	chained_irq_exit(chip, desc);
 }
 
 static int sunxi_pinctrl_add_function(struct sunxi_pinctrl *pctl,