gpio: lynxpoint: Move hardware initialization to callback

The driver wants to initialize related registers before IRQ chip will be added.
That's why move it to a corresponding callback. It also fixes the NULL pointer
dereference.

Fixes: 7b1e889436a1 ("gpio: lynxpoint: Pass irqchip when adding gpiochip")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-lynxpoint.c b/drivers/gpio/gpio-lynxpoint.c
index 6bb9741..082cd14 100644 (file)
--- a/drivers/gpio/gpio-lynxpoint.c
+++ b/drivers/gpio/gpio-lynxpoint.c
@@ -294,8 +294,9 @@ static struct irq_chip lp_irqchip = {
        .flags = IRQCHIP_SKIP_SET_WAKE,
 };
 
-static void lp_gpio_irq_init_hw(struct lp_gpio *lg)
+static int lp_gpio_irq_init_hw(struct gpio_chip *chip)
 {
+       struct lp_gpio *lg = gpiochip_get_data(chip);
        unsigned long reg;
        unsigned base;
 
@@ -307,6 +308,8 @@ static void lp_gpio_irq_init_hw(struct lp_gpio *lg)
                reg = lp_gpio_reg(&lg->chip, base, LP_INT_STAT);
                outl(0xffffffff, reg);
        }
+
+       return 0;
 }
 
 static int lp_gpio_probe(struct platform_device *pdev)
@@ -364,6 +367,7 @@ static int lp_gpio_probe(struct platform_device *pdev)
 
                girq = &gc->irq;
                girq->chip = &lp_irqchip;
+               girq->init_hw = lp_gpio_irq_init_hw;
                girq->parent_handler = lp_gpio_irq_handler;
                girq->num_parents = 1;
                girq->parents = devm_kcalloc(&pdev->dev, girq->num_parents,
@@ -374,8 +378,6 @@ static int lp_gpio_probe(struct platform_device *pdev)
                girq->parents[0] = (unsigned)irq_rc->start;
                girq->default_type = IRQ_TYPE_NONE;
                girq->handler = handle_simple_irq;
-
-               lp_gpio_irq_init_hw(lg);
        }
 
        ret = devm_gpiochip_add_data(dev, gc, lg);