[media] v4l2-core: Add support for touch devices

Some touch controllers send out touch data in a similar way to a
greyscale frame grabber.

Add new device type VFL_TYPE_TOUCH:
- This uses a new device prefix v4l-touch for these devices, to stop
  generic capture software from treating them as webcams. Otherwise,
  touch is treated similarly to video capture.
- Add V4L2_INPUT_TYPE_TOUCH
- Add MEDIA_INTF_T_V4L_TOUCH
- Add V4L2_CAP_TOUCH to indicate device is a touch device

Add formats:
- V4L2_TCH_FMT_DELTA_TD16 for signed 16-bit touch deltas
- V4L2_TCH_FMT_DELTA_TD08 for signed 16-bit touch deltas
- V4L2_TCH_FMT_TU16 for unsigned 16-bit touch data
- V4L2_TCH_FMT_TU08 for unsigned 8-bit touch data

This support will be used by:
- Atmel maXTouch (atmel_mxt_ts)
- Synaptics RMI4.
- sur40

Signed-off-by: Nick Dyer <nick@shmanahar.org>
Tested-by: Chris Healy <cphealy@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/media/kapi/v4l2-dev.rst b/Documentation/media/kapi/v4l2-dev.rst
index d07258a..5782be7 100644 (file)
--- a/Documentation/media/kapi/v4l2-dev.rst
+++ b/Documentation/media/kapi/v4l2-dev.rst
@@ -200,6 +200,7 @@ types exist:
 - ``VFL_TYPE_VBI``: ``/dev/vbiX`` for vertical blank data (i.e. closed captions, teletext)
 - ``VFL_TYPE_RADIO``: ``/dev/radioX`` for radio tuners
 - ``VFL_TYPE_SDR``: ``/dev/swradioX`` for Software Defined Radio tuners
+- ``VFL_TYPE_TOUCH``: ``/dev/v4l-touchX`` for touch sensors
 
 The last argument gives you a certain amount of control over the device
 device node number used (i.e. the X in ``videoX``). Normally you will pass -1

diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index d8a2299..9014362 100644 (file)
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -65,6 +65,8 @@ static inline const char *intf_type(struct media_interface *intf)
                return "v4l-subdev";
        case MEDIA_INTF_T_V4L_SWRADIO:
                return "v4l-swradio";
+       case MEDIA_INTF_T_V4L_TOUCH:
+               return "v4l-touch";
        case MEDIA_INTF_T_ALSA_PCM_CAPTURE:
                return "alsa-pcm-capture";
        case MEDIA_INTF_T_ALSA_PCM_PLAYBACK:

diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
index e6da353..8be561a 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-dev.c
+++ b/drivers/media/v4l2-core/v4l2-dev.c
@@ -527,6 +527,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
        bool is_vbi = vdev->vfl_type == VFL_TYPE_VBI;
        bool is_radio = vdev->vfl_type == VFL_TYPE_RADIO;
        bool is_sdr = vdev->vfl_type == VFL_TYPE_SDR;
+       bool is_tch = vdev->vfl_type == VFL_TYPE_TOUCH;
        bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
        bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
 
@@ -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_tch) {
                /* 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_tch) {
                /* 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_tch) {
                /* ioctls valid for video or vbi */
                if (ops->vidioc_s_std)
                        set_bit(_IOC_NR(VIDIOC_ENUMSTD), valid_ioctls);
@@ -751,6 +752,10 @@ static int video_register_media_controller(struct video_device *vdev, int type)
                intf_type = MEDIA_INTF_T_V4L_SWRADIO;
                vdev->entity.function = MEDIA_ENT_F_IO_SWRADIO;
                break;
+       case VFL_TYPE_TOUCH:
+               intf_type = MEDIA_INTF_T_V4L_TOUCH;
+               vdev->entity.function = MEDIA_ENT_F_IO_V4L;
+               break;
        case VFL_TYPE_RADIO:
                intf_type = MEDIA_INTF_T_V4L_RADIO;
                /*
@@ -854,6 +859,9 @@ 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:
+               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 51a0fa1..eb6ccc7 100644 (file)
--- 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_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
        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_tch) && is_rx &&
                    (ops->vidioc_g_fmt_vid_cap || ops->vidioc_g_fmt_vid_cap_mplane))
                        return 0;
                break;
@@ -1243,6 +1244,10 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
        case V4L2_SDR_FMT_CS8:          descr = "Complex S8"; break;
        case V4L2_SDR_FMT_CS14LE:       descr = "Complex S14LE"; break;
        case V4L2_SDR_FMT_RU12LE:       descr = "Real U12LE"; break;
+       case V4L2_TCH_FMT_DELTA_TD16:   descr = "16-bit signed deltas"; break;
+       case V4L2_TCH_FMT_DELTA_TD08:   descr = "8-bit signed deltas"; break;
+       case V4L2_TCH_FMT_TU16:         descr = "16-bit unsigned touch data"; break;
+       case V4L2_TCH_FMT_TU08:         descr = "8-bit unsigned touch data"; break;
 
        default:
                /* Compressed formats */
@@ -1309,13 +1314,14 @@ 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_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
        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_tch) || !ops->vidioc_enum_fmt_vid_cap))
                        break;
                ret = ops->vidioc_enum_fmt_vid_cap(file, fh, arg);
                break;
@@ -1362,6 +1368,7 @@ 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_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
        bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
        bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
        int ret;
@@ -1392,7 +1399,7 @@ 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_tch) || !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);
@@ -1451,6 +1458,21 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
        return -EINVAL;
 }
 
+static void v4l_pix_format_touch(struct v4l2_pix_format *p)
+{
+       /*
+        * The v4l2_pix_format structure contains fields that make no sense for
+        * touch. Set them to default values in this case.
+        */
+
+       p->field = V4L2_FIELD_NONE;
+       p->colorspace = V4L2_COLORSPACE_RAW;
+       p->flags = 0;
+       p->ycbcr_enc = 0;
+       p->quantization = 0;
+       p->xfer_func = 0;
+}
+
 static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
                                struct file *file, void *fh, void *arg)
 {
@@ -1458,6 +1480,7 @@ 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_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
        bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
        bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
        int ret;
@@ -1469,12 +1492,14 @@ 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_tch) || !ops->vidioc_s_fmt_vid_cap))
                        break;
                CLEAR_AFTER_FIELD(p, fmt.pix);
                ret = ops->vidioc_s_fmt_vid_cap(file, fh, arg);
                /* just in case the driver zeroed it again */
                p->fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
+               if (is_tch)
+                       v4l_pix_format_touch(&p->fmt.pix);
                return ret;
        case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
                if (unlikely(!is_rx || !is_vid || !ops->vidioc_s_fmt_vid_cap_mplane))
@@ -1545,6 +1570,7 @@ 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_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
        bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
        bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
        int ret;
@@ -1553,7 +1579,7 @@ 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_tch) || !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 a122b1b..5272aee 100644 (file)
--- 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         5
+#define VFL_TYPE_MAX           6
 
 /* Is this a receiver, transmitter or mem-to-mem? */
 /* Ignored for VFL_TYPE_SUBDEV. */
@@ -294,6 +295,7 @@ struct video_device
  *     - %VFL_TYPE_RADIO - A radio card
  *     - %VFL_TYPE_SUBDEV - A subdevice
  *     - %VFL_TYPE_SDR - Software Defined Radio
+ *     - %VFL_TYPE_TOUCH - A touch sensor
  *
  * .. note::
  *

diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
index 7acf0f6..4890787 100644 (file)
--- a/include/uapi/linux/media.h
+++ b/include/uapi/linux/media.h
@@ -307,6 +307,7 @@ struct media_links_enum {
 #define MEDIA_INTF_T_V4L_RADIO  (MEDIA_INTF_T_V4L_BASE + 2)
 #define MEDIA_INTF_T_V4L_SUBDEV (MEDIA_INTF_T_V4L_BASE + 3)
 #define MEDIA_INTF_T_V4L_SWRADIO (MEDIA_INTF_T_V4L_BASE + 4)
+#define MEDIA_INTF_T_V4L_TOUCH (MEDIA_INTF_T_V4L_BASE + 5)
 
 #define MEDIA_INTF_T_ALSA_PCM_CAPTURE   (MEDIA_INTF_T_ALSA_BASE)
 #define MEDIA_INTF_T_ALSA_PCM_PLAYBACK  (MEDIA_INTF_T_ALSA_BASE + 1)

diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 724f43e..22bad8c 100644 (file)
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -440,6 +440,8 @@ struct v4l2_capability {
 #define V4L2_CAP_ASYNCIO                0x02000000  /* async I/O */
 #define V4L2_CAP_STREAMING              0x04000000  /* streaming I/O ioctls */
 
+#define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */
+
 #define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */
 
 /*
@@ -635,6 +637,12 @@ struct v4l2_pix_format {
 #define V4L2_SDR_FMT_CS14LE       v4l2_fourcc('C', 'S', '1', '4') /* complex s14le */
 #define V4L2_SDR_FMT_RU12LE       v4l2_fourcc('R', 'U', '1', '2') /* real u12le */
 
+/* Touch formats - used for Touch devices */
+#define V4L2_TCH_FMT_DELTA_TD16        v4l2_fourcc('T', 'D', '1', '6') /* 16-bit signed deltas */
+#define V4L2_TCH_FMT_DELTA_TD08        v4l2_fourcc('T', 'D', '0', '8') /* 8-bit signed deltas */
+#define V4L2_TCH_FMT_TU16      v4l2_fourcc('T', 'U', '1', '6') /* 16-bit unsigned touch data */
+#define V4L2_TCH_FMT_TU08      v4l2_fourcc('T', 'U', '0', '8') /* 8-bit unsigned touch data */
+
 /* priv field value to indicates that subsequent fields are valid. */
 #define V4L2_PIX_FMT_PRIV_MAGIC                0xfeedcafe
 
@@ -1401,6 +1409,7 @@ 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          3
 
 /* field 'status' - general */
 #define V4L2_IN_ST_NO_POWER    0x00000001  /* Attached device is off */