@@ -735,6 +735,7 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
static int lineevent_create(struct gpio_device *gdev, void __user *ip)
{
+ struct gpio_chip *chip = gdev->chip;
struct gpioevent_request eventreq;
struct lineevent_state *le;
struct gpio_desc *desc;
@@ -807,7 +808,8 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
goto out_free_desc;
le->irq = gpiod_to_irq(desc);
- if (le->irq <= 0) {
+ /* Mockup gpiochips don't have to support this. */
+ if (le->irq <= 0 && !chip->mockup) {
ret = -ENODEV;
goto out_free_desc;
}
@@ -823,15 +825,20 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
init_waitqueue_head(&le->wait);
mutex_init(&le->read_lock);
- /* Request a thread to read the events */
- ret = request_threaded_irq(le->irq,
- NULL,
- lineevent_irq_thread,
- irqflags,
- le->label,
- le);
- if (ret)
- goto out_free_desc;
+ if (!chip->mockup) {
+ /*
+ * Request a thread to read the events unless we're dealing
+ * with a mockup gpiochip.
+ */
+ ret = request_threaded_irq(le->irq,
+ NULL,
+ lineevent_irq_thread,
+ irqflags,
+ le->label,
+ le);
+ if (ret)
+ goto out_free_desc;
+ }
fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
if (fd < 0) {
@@ -82,6 +82,9 @@ enum single_ended_mode {
* implies that if the chip supports IRQs, these IRQs need to be threaded
* as the chip access may sleep when e.g. reading out the IRQ status
* registers.
+ * @mockup: if set, the flag signifies that this gpiochip does not model a
+ * real device; this can affect the way the chip is handled internally
+ * by gpiolib.
* @read_reg: reader function for generic GPIO
* @write_reg: writer function for generic GPIO
* @pin2mask: some generic GPIO controllers work with the big-endian bits
@@ -166,6 +169,7 @@ struct gpio_chip {
u16 ngpio;
const char *const *names;
bool can_sleep;
+ bool mockup;
#if IS_ENABLED(CONFIG_GPIO_GENERIC)
unsigned long (*read_reg)(void __iomem *reg);
Add a new flag to struct gpio_chip indicating that the chip doesn't model a real device. When setting up the line event queue, check if a device is a mockup chip and don't actually request the interrupt. This way we can monitor mockup GPIOs. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> --- drivers/gpio/gpiolib.c | 27 +++++++++++++++++---------- include/linux/gpio/driver.h | 4 ++++ 2 files changed, 21 insertions(+), 10 deletions(-) -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html