[PATCH v5 09/12] media: uvcvideo: Implement UVC_QUIRK_PRIVACY_DURING_STREAM

[Ricardo Ribalda]

Some devices, can only read the privacy_pin if the device is
streaming.

This patch implement a quirk for such devices, in order to avoid invalid
reads and/or spurious events.

Signed-off-by: Ricardo Ribalda <riba...@chromium.org>
---
 drivers/media/usb/uvc/uvc_driver.c | 57 ++++++++++++++++++++++++++++--
 drivers/media/usb/uvc/uvc_queue.c  |  3 ++
 drivers/media/usb/uvc/uvcvideo.h   |  4 +++
 3 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_driver.c 
b/drivers/media/usb/uvc/uvc_driver.c
index 72516101fdd0..7af37d4bd60a 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/atomic.h>
+#include <linux/dmi.h>
 #include <linux/gpio/consumer.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -1472,6 +1473,17 @@ static int uvc_parse_control(struct uvc_device *dev)
 /* 
-----------------------------------------------------------------------------
  * Privacy GPIO
  */
+static bool uvc_gpio_is_streaming(struct uvc_device *dev)
+{
+       struct uvc_streaming *streaming;
+
+       list_for_each_entry(streaming, &dev->streams, list) {
+               if (uvc_queue_streaming(&streaming->queue))
+                       return true;
+       }
+
+       return false;
+}
 
 
 static u8 uvc_gpio_update_value(struct uvc_device *dev,
@@ -1499,7 +1511,12 @@ static int uvc_gpio_get_cur(struct uvc_device *dev, 
struct uvc_entity *entity,
        if (cs != UVC_CT_PRIVACY_CONTROL || size < 1)
                return -EINVAL;
 
+       if ((dev->quirks & UVC_QUIRK_PRIVACY_DURING_STREAM) &&
+           !uvc_gpio_is_streaming(dev))
+               return -EBUSY;
+
        *(uint8_t *)data = uvc_gpio_update_value(dev, entity);
+
        return 0;
 }
 
@@ -1528,19 +1545,50 @@ static struct uvc_entity *uvc_gpio_find_entity(struct 
uvc_device *dev)
        return NULL;
 }
 
-static irqreturn_t uvc_gpio_irq(int irq, void *data)
+void uvc_privacy_gpio_event(struct uvc_device *dev)
 {
-       struct uvc_device *dev = data;
        struct uvc_entity *unit;
 
+
        unit = uvc_gpio_find_entity(dev);
        if (!unit)
-               return IRQ_HANDLED;
+               return;
 
        uvc_gpio_update_value(dev, unit);
+}
+
+static irqreturn_t uvc_gpio_irq(int irq, void *data)
+{
+       struct uvc_device *dev = data;
+
+       /* Ignore privacy events during streamoff */
+       if (dev->quirks & UVC_QUIRK_PRIVACY_DURING_STREAM)
+               if (!uvc_gpio_is_streaming(dev))
+                       return IRQ_HANDLED;
+
+       uvc_privacy_gpio_event(dev);
+
        return IRQ_HANDLED;
 }
 
+static const struct dmi_system_id privacy_valid_during_streamon[] = {
+       {
+               .ident = "HP Elite c1030 Chromebook",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "Jinlon"),
+               },
+       },
+       {
+               .ident = "HP Pro c640 Chromebook",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "Dratini"),
+               },
+       },
+       { } /* terminate list */
+};
+
 static int uvc_gpio_parse(struct uvc_device *dev)
 {
        struct uvc_entity *unit;
@@ -1577,6 +1625,9 @@ static int uvc_gpio_parse(struct uvc_device *dev)
 
        list_add_tail(&unit->list, &dev->entities);
 
+       if (dmi_check_system(privacy_valid_during_streamon))
+               dev->quirks |= UVC_QUIRK_PRIVACY_DURING_STREAM;
+
        return 0;
 }
 
diff --git a/drivers/media/usb/uvc/uvc_queue.c 
b/drivers/media/usb/uvc/uvc_queue.c
index cd60c6c1749e..e800d491303f 100644
--- a/drivers/media/usb/uvc/uvc_queue.c
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -337,9 +337,12 @@ int uvc_dequeue_buffer(struct uvc_video_queue *queue, 
struct v4l2_buffer *buf,
 int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
        int ret;
+       struct uvc_streaming *stream = uvc_queue_to_stream(queue);
 
        mutex_lock(&queue->mutex);
        ret = vb2_streamon(&queue->queue, type);
+       if (stream->dev->quirks & UVC_QUIRK_PRIVACY_DURING_STREAM)
+               uvc_privacy_gpio_event(stream->dev);
        mutex_unlock(&queue->mutex);
 
        return ret;
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 079a407ebba5..32c1ba246d97 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -209,6 +209,7 @@
 #define UVC_QUIRK_RESTORE_CTRLS_ON_INIT        0x00000400
 #define UVC_QUIRK_FORCE_Y8             0x00000800
 #define UVC_QUIRK_FORCE_BPP            0x00001000
+#define UVC_QUIRK_PRIVACY_DURING_STREAM        0x00002000
 
 /* Format flags */
 #define UVC_FMT_FLAG_COMPRESSED                0x00000001
@@ -826,6 +827,9 @@ extern const struct v4l2_file_operations uvc_fops;
 int uvc_mc_register_entities(struct uvc_video_chain *chain);
 void uvc_mc_cleanup_entity(struct uvc_entity *entity);
 
+/* Privacy gpio */
+void uvc_privacy_gpio_event(struct uvc_device *dev);
+
 /* Video */
 int uvc_video_init(struct uvc_streaming *stream);
 int uvc_video_suspend(struct uvc_streaming *stream);
-- 
2.29.2.684.gfbc64c5ab5-goog