gpio: pch: check the return value of irq_alloc_generic_chip()

This function can fail, so check the return value before dereferencing
the returned pointer.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-pch.c b/drivers/gpio/gpio-pch.c
index 71bc6da1133727eaa59d8d0c52a3c84d02eea6ff..f6600f8ada520645bad21728c52252c67f196a0b 100644 (file)
--- a/drivers/gpio/gpio-pch.c
+++ b/drivers/gpio/gpio-pch.c
@@ -331,14 +331,18 @@ static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
        return ret;
 }
 
-static void pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
-                               unsigned int irq_start, unsigned int num)
+static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
+                                      unsigned int irq_start,
+                                      unsigned int num)
 {
        struct irq_chip_generic *gc;
        struct irq_chip_type *ct;
 
        gc = irq_alloc_generic_chip("pch_gpio", 1, irq_start, chip->base,
                                    handle_simple_irq);
+       if (!gc)
+               return -ENOMEM;
+
        gc->private = chip;
        ct = gc->chip_types;
 
@@ -349,6 +353,8 @@ static void pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
 
        irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
                               IRQ_NOREQUEST | IRQ_NOPROBE, 0);
+
+       return 0;
 }
 
 static int pch_gpio_probe(struct pci_dev *pdev,
@@ -425,7 +431,10 @@ static int pch_gpio_probe(struct pci_dev *pdev,
                goto err_request_irq;
        }
 
-       pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
+       ret = pch_gpio_alloc_generic_chip(chip, irq_base,
+                                         gpio_pins[chip->ioh]);
+       if (ret)
+               goto err_request_irq;
 
 end:
        return 0;