diff options
| -rw-r--r-- | drivers/gpio/gpiolib.c | 15 | ||||
| -rw-r--r-- | include/asm-generic/gpio.h | 2 |
2 files changed, 14 insertions, 3 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index d8db2f8ee41..eb75d12e83b 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -68,6 +68,9 @@ static void gpio_ensure_requested(struct gpio_desc *desc) if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { pr_warning("GPIO-%d autorequested\n", (int)(desc - gpio_desc)); desc_set_label(desc, "[auto]"); + if (!try_module_get(desc->chip->owner)) + pr_err("GPIO-%d: module can't be gotten \n", + (int)(desc - gpio_desc)); } } @@ -177,6 +180,9 @@ int gpio_request(unsigned gpio, const char *label) if (desc->chip == NULL) goto done; + if (!try_module_get(desc->chip->owner)) + goto done; + /* NOTE: gpio_request() can be called in early boot, * before IRQs are enabled. */ @@ -184,8 +190,10 @@ int gpio_request(unsigned gpio, const char *label) if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { desc_set_label(desc, label ? : "?"); status = 0; - } else + } else { status = -EBUSY; + module_put(desc->chip->owner); + } done: if (status) @@ -209,9 +217,10 @@ void gpio_free(unsigned gpio) spin_lock_irqsave(&gpio_lock, flags); desc = &gpio_desc[gpio]; - if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags)) + if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags)) { desc_set_label(desc, NULL); - else + module_put(desc->chip->owner); + } else WARN_ON(extra_checks); spin_unlock_irqrestore(&gpio_lock, flags); diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index f29a502f4a6..7e77b6ff45b 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -17,6 +17,7 @@ #endif struct seq_file; +struct module; /** * struct gpio_chip - abstract a GPIO controller @@ -48,6 +49,7 @@ struct seq_file; */ struct gpio_chip { char *label; + struct module *owner; int (*direction_input)(struct gpio_chip *chip, unsigned offset); |