[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 <riba...@chromium.org>
---
 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