[PATCH 6/6] media: uvcvideo: Handle IRQs from the privacy_pin

[Ricardo Ribalda]

If the privacy pin produces an IRQ, read the gpio and notify userspace
via an event.

Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
 drivers/media/usb/uvc/uvc_ctrl.c   |  3 +++
 drivers/media/usb/uvc/uvc_driver.c | 30 ++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 3a49a1326a90..00c41cba0f68 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1346,6 +1346,9 @@ static void uvc_ctrl_status_event_work(struct work_struct *work)
 
 	mutex_unlock(&chain->ctrl_mutex);
 
+	if (!w->urb)
+		return;
+
 	/* Resubmit the URB. */
 	w->urb->interval = dev->int_ep->desc.bInterval;
 	ret = usb_submit_urb(w->urb, GFP_KERNEL);
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 180e503e900f..d1260d131bd8 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -1460,6 +1460,25 @@ static int uvc_gpio_get_info(struct uvc_entity *entity, u8 cs, u8 *caps)
 	return 0;
 }
 
+static irqreturn_t uvc_privacy_gpio_irq(int irq, void *data)
+{
+	struct uvc_device *dev = data;
+	struct uvc_video_chain *chain;
+	struct uvc_entity *term;
+	u8 value;
+
+	list_for_each_entry(chain, &dev->chains, list) {
+		list_for_each_entry(term, &dev->entities, list) {
+			if (UVC_ENTITY_TYPE(term) == UVC_GPIO_UNIT) {
+				value = gpiod_get_value(term->gpio.gpio_privacy);
+				uvc_ctrl_status_event(NULL, chain, term->controls, &value);
+			}
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
 static int uvc_parse_gpio(struct uvc_device *dev)
 {
 	struct uvc_entity *unit;
@@ -1490,6 +1509,17 @@ static int uvc_parse_gpio(struct uvc_device *dev)
 
 	list_add_tail(&unit->list, &dev->entities);
 
+	irq = gpiod_to_irq(gpio_privacy);
+
+	if (irq == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+
+	if (irq < 0)
+		return 0;
+
+	ret = devm_request_irq(&dev->udev->dev, irq, uvc_privacy_gpio_irq, IRQF_SHARED,
+			       "uvc_privacy_gpio", dev);
+
 	return 0;
 }
 
-- 
2.29.0.rc1.297.gfa9743e501-goog