[PATCH v3 3/8] [media] v4l2-core: Add VFL_TYPE_TOUCH_SENSOR

Nick Dyer
2016-06-01T16:40:13Z

Some touch controllers send out raw touch data in a similar way to a
greyscale frame grabber. Add a new device type for these devices.

Use a new device prefix v4l-touch for these devices, to stop generic
capture software from treating them as webcams.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
---
drivers/input/touchscreen/sur40.c | 2 +-
drivers/media/v4l2-core/v4l2-dev.c | 13 ++++++++++---
drivers/media/v4l2-core/v4l2-ioctl.c | 15 ++++++++++-----
include/media/v4l2-dev.h | 3 ++-
include/uapi/linux/videodev2.h | 1 +
5 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c
index 880c40b..7e5fe2b 100644
--- a/drivers/input/touchscreen/sur40.c
+++ b/drivers/input/touchscreen/sur40.c
@@ -599,7 +599,7 @@ static int sur40_probe(struct usb_interface *interface,
sur40->vdev.queue = &sur40->queue;
video_set_drvdata(&sur40->vdev, sur40);

- error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1);
+ error = video_register_device(&sur40->vdev, VFL_TYPE_TOUCH_SENSOR, -1);
if (error) {
dev_err(&interface->dev,
"Unable to register video subdevice.");
diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
index 70b559d..7068e12 100644
--- a/drivers/media/v4l2-core/v4l2-dev.c
+++ b/drivers/media/v4l2-core/v4l2-dev.c
@@ -529,6 +529,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
bool is_sdr = vdev->vfl_type == VFL_TYPE_SDR;
bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
+ bool is_touch = vdev->vfl_type == VFL_TYPE_TOUCH_SENSOR;

bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);

@@ -573,7 +574,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
if (ops->vidioc_enum_freq_bands || ops->vidioc_g_tuner || ops->vidioc_g_modulator)
set_bit(_IOC_NR(VIDIOC_ENUM_FREQ_BANDS), valid_ioctls);

- if (is_vid) {
+ if (is_vid || is_touch) {
/* video specific ioctls */
if ((is_rx && (ops->vidioc_enum_fmt_vid_cap ||
ops->vidioc_enum_fmt_vid_cap_mplane ||
@@ -662,7 +663,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
}

- if (is_vid || is_vbi || is_sdr) {
+ if (is_vid || is_vbi || is_sdr || is_touch) {
/* ioctls valid for video, vbi or sdr */
SET_VALID_IOCTL(ops, VIDIOC_REQBUFS, vidioc_reqbufs);
SET_VALID_IOCTL(ops, VIDIOC_QUERYBUF, vidioc_querybuf);
@@ -675,7 +676,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
SET_VALID_IOCTL(ops, VIDIOC_STREAMOFF, vidioc_streamoff);
}

- if (is_vid || is_vbi) {
+ if (is_vid || is_vbi || is_touch) {
/* ioctls valid for video or vbi */
if (ops->vidioc_s_std)
set_bit(_IOC_NR(VIDIOC_ENUMSTD), valid_ioctls);
@@ -739,6 +740,7 @@ static int video_register_media_controller(struct video_device *vdev, int type)
vdev->entity.function = MEDIA_ENT_F_UNKNOWN;

switch (type) {
+ case VFL_TYPE_TOUCH_SENSOR:
case VFL_TYPE_GRABBER:
intf_type = MEDIA_INTF_T_V4L_VIDEO;
vdev->entity.function = MEDIA_ENT_F_IO_V4L;
@@ -845,6 +847,8 @@ static int video_register_media_controller(struct video_device *vdev, int type)
* %VFL_TYPE_SUBDEV - A subdevice
*
* %VFL_TYPE_SDR - Software Defined Radio
+ *
+ * %VFL_TYPE_TOUCH_SENSOR - A touch sensor
*/
int __video_register_device(struct video_device *vdev, int type, int nr,
int warn_if_nr_in_use, struct module *owner)
@@ -888,6 +892,9 @@ int __video_register_device(struct video_device *vdev, int type, int nr,
/* Use device name 'swradio' because 'sdr' was already taken. */
name_base = "swradio";
break;
+ case VFL_TYPE_TOUCH_SENSOR:
+ name_base = "v4l-touch";
+ break;
default:
printk(KERN_ERR "%s called with unknown type: %d\n",
__func__, type);
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index ecf7e0b..352c4d0 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -924,6 +924,7 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)
bool is_vid = vfd->vfl_type == VFL_TYPE_GRABBER;
bool is_vbi = vfd->vfl_type == VFL_TYPE_VBI;
bool is_sdr = vfd->vfl_type == VFL_TYPE_SDR;
+ bool is_touch = vfd->vfl_type == VFL_TYPE_TOUCH_SENSOR;
bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
bool is_tx = vfd->vfl_dir != VFL_DIR_RX;

@@ -932,7 +933,7 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)

switch (type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
- if (is_vid && is_rx &&
+ if ((is_vid || is_touch) && is_rx &&
(ops->vidioc_g_fmt_vid_cap || ops->vidioc_g_fmt_vid_cap_mplane))
return 0;
break;
@@ -1310,13 +1311,14 @@ static int v4l_enum_fmt(const struct v4l2_ioctl_ops *ops,
struct video_device *vfd = video_devdata(file);
bool is_vid = vfd->vfl_type == VFL_TYPE_GRABBER;
bool is_sdr = vfd->vfl_type == VFL_TYPE_SDR;
+ bool is_touch = vfd->vfl_type == VFL_TYPE_TOUCH_SENSOR;
bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
int ret = -EINVAL;

switch (p->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
- if (unlikely(!is_rx || !is_vid || !ops->vidioc_enum_fmt_vid_cap))
+ if (unlikely(!is_rx || (!is_vid && !is_touch) || !ops->vidioc_enum_fmt_vid_cap))
break;
ret = ops->vidioc_enum_fmt_vid_cap(file, fh, arg);
break;
@@ -1363,6 +1365,7 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
struct video_device *vfd = video_devdata(file);
bool is_vid = vfd->vfl_type == VFL_TYPE_GRABBER;
bool is_sdr = vfd->vfl_type == VFL_TYPE_SDR;
+ bool is_touch = vfd->vfl_type == VFL_TYPE_TOUCH_SENSOR;
bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
int ret;
@@ -1393,7 +1396,7 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,

switch (p->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
- if (unlikely(!is_rx || !is_vid || !ops->vidioc_g_fmt_vid_cap))
+ if (unlikely(!is_rx || (!is_vid && !is_touch) || !ops->vidioc_g_fmt_vid_cap))
break;
p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
ret = ops->vidioc_g_fmt_vid_cap(file, fh, arg);
@@ -1459,6 +1462,7 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
struct video_device *vfd = video_devdata(file);
bool is_vid = vfd->vfl_type == VFL_TYPE_GRABBER;
bool is_sdr = vfd->vfl_type == VFL_TYPE_SDR;
+ bool is_touch = vfd->vfl_type == VFL_TYPE_TOUCH_SENSOR;
bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
int ret;
@@ -1470,7 +1474,7 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,

switch (p->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
- if (unlikely(!is_rx || !is_vid || !ops->vidioc_s_fmt_vid_cap))
+ if (unlikely(!is_rx || (!is_vid && !is_touch) || !ops->vidioc_s_fmt_vid_cap))
break;
CLEAR_AFTER_FIELD(p, fmt.pix);
ret = ops->vidioc_s_fmt_vid_cap(file, fh, arg);
@@ -1546,6 +1550,7 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
struct video_device *vfd = video_devdata(file);
bool is_vid = vfd->vfl_type == VFL_TYPE_GRABBER;
bool is_sdr = vfd->vfl_type == VFL_TYPE_SDR;
+ bool is_touch = vfd->vfl_type == VFL_TYPE_TOUCH_SENSOR;
bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
int ret;
@@ -1554,7 +1559,7 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,

switch (p->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
- if (unlikely(!is_rx || !is_vid || !ops->vidioc_try_fmt_vid_cap))
+ if (unlikely(!is_rx || (!is_vid && !is_touch) || !ops->vidioc_try_fmt_vid_cap))
break;
CLEAR_AFTER_FIELD(p, fmt.pix);
ret = ops->vidioc_try_fmt_vid_cap(file, fh, arg);
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index 25a3190..99eb87a 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -25,7 +25,8 @@
#define VFL_TYPE_RADIO 2
#define VFL_TYPE_SUBDEV 3
#define VFL_TYPE_SDR 4
-#define VFL_TYPE_MAX 5
+#define VFL_TYPE_TOUCH_SENSOR 5
+#define VFL_TYPE_MAX 6

/* Is this a receiver, transmitter or mem-to-mem? */
/* Ignored for VFL_TYPE_SUBDEV. */
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index e0125cf..765a6cb 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -1400,6 +1400,7 @@ struct v4l2_input {
/* Values for the 'type' field */
#define V4L2_INPUT_TYPE_TUNER 1
#define V4L2_INPUT_TYPE_CAMERA 2
+#define V4L2_INPUT_TYPE_TOUCH_SENSOR 3

/* field 'status' - general */
#define V4L2_IN_ST_NO_POWER 0x00000001 /* Attached device is off */
--
2.5.0