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

Ricardo Ribalda
2020-12-21T18:44:19Z

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 <ribalda@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