This patch add support for the raw video stream from the Samsung SUR40 touchscreen device. Existing input device support is not affected by this patch and can be used concurrently. videobuf2-dma-contig is used for buffer management. All tests from current v4l2-compliance -s run pass (see http://floe.butterbrot.org/external/results.txt for details). Note: I'm intentionally using dma-contig instead of vmalloc, as the USB core apparently _will_ try to use DMA for larger bulk transfers. Signed-off-by: Florian Echtler <floe@xxxxxxxxxxxxxx> --- drivers/input/touchscreen/sur40.c | 423 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 411 insertions(+), 12 deletions(-) diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c index f1cb051..bcd9ee2 100644 --- a/drivers/input/touchscreen/sur40.c +++ b/drivers/input/touchscreen/sur40.c @@ -1,7 +1,7 @@ /* * Surface2.0/SUR40/PixelSense input driver * - * Copyright (c) 2013 by Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx> + * Copyright (c) 2014 by Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx> * * Derived from the USB Skeleton driver 1.1, * Copyright (c) 2003 Greg Kroah-Hartman (greg@xxxxxxxxx) @@ -12,6 +12,9 @@ * and from the generic hid-multitouch driver, * Copyright (c) 2010-2012 Stephane Chatty <chatty@xxxxxxx> * + * and from the v4l2-pci-skeleton driver, + * Copyright (c) Copyright 2014 Cisco Systems, Inc. + * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of @@ -31,6 +34,11 @@ #include <linux/input-polldev.h> #include <linux/input/mt.h> #include <linux/usb/input.h> +#include <linux/videodev2.h> +#include <media/v4l2-device.h> +#include <media/v4l2-dev.h> +#include <media/v4l2-ioctl.h> +#include <media/videobuf2-dma-contig.h> /* read 512 bytes from endpoint 0x86 -> get header + blobs */ struct sur40_header { @@ -82,9 +90,19 @@ struct sur40_data { struct sur40_blob blobs[]; } __packed; +/* read 512 bytes from endpoint 0x82 -> get header below + * continue reading 16k blocks until header.size bytes read */ +struct sur40_image_header { + __le32 magic; /* "SUBF" */ + __le32 packet_id; + __le32 size; /* always 0x0007e900 = 960x540 */ + __le32 timestamp; /* milliseconds (increases by 16 or 17 each frame) */ + __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ +} __packed; /* version information */ #define DRIVER_SHORT "sur40" +#define DRIVER_LONG "Samsung SUR40" #define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx>" #define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver" @@ -99,6 +117,13 @@ struct sur40_data { /* touch data endpoint */ #define TOUCH_ENDPOINT 0x86 +/* video data endpoint */ +#define VIDEO_ENDPOINT 0x82 + +/* video header fields */ +#define VIDEO_HEADER_MAGIC 0x46425553 +#define VIDEO_PACKET_SIZE 16384 + /* polling interval (ms) */ #define POLL_INTERVAL 10 @@ -113,21 +138,23 @@ struct sur40_data { #define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */ #define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */ -/* - * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT - * here by mistake which is very likely to have corrupted the firmware EEPROM - * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug. - * Should you ever run into a similar problem, the background story to this - * incident and instructions on how to fix the corrupted EEPROM are available - * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html -*/ - +/* master device state */ struct sur40_state { struct usb_device *usbdev; struct device *dev; struct input_polled_dev *input; + struct v4l2_device v4l2; + struct video_device vdev; + struct mutex lock; + + struct vb2_queue queue; + struct vb2_alloc_ctx *alloc_ctx; + struct list_head buf_list; + spinlock_t qlock; + int sequence; + struct sur40_data *bulk_in_buffer; size_t bulk_in_size; u8 bulk_in_epaddr; @@ -135,6 +162,27 @@ struct sur40_state { char phys[64]; }; +struct sur40_buffer { + struct vb2_buffer vb; + struct list_head list; +}; + +/* forward declarations */ +static struct video_device sur40_video_device; +static struct v4l2_pix_format sur40_video_format; +static struct vb2_queue sur40_queue; +static void sur40_process_video(struct sur40_state *sur40); + +/* + * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT + * here by mistake which is very likely to have corrupted the firmware EEPROM + * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug. + * Should you ever run into a similar problem, the background story to this + * incident and instructions on how to fix the corrupted EEPROM are available + * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html +*/ + +/* command wrapper */ static int sur40_command(struct sur40_state *dev, u8 command, u16 index, void *buffer, u16 size) { @@ -247,7 +295,6 @@ static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input) /* core function: poll for new input data */ static void sur40_poll(struct input_polled_dev *polldev) { - struct sur40_state *sur40 = polldev->private; struct input_dev *input = polldev->input; int result, bulk_read, need_blobs, packet_blobs, i; @@ -314,6 +361,79 @@ static void sur40_poll(struct input_polled_dev *polldev) input_mt_sync_frame(input); input_sync(input); + + sur40_process_video(sur40); +} + +/* deal with video data */ +static void sur40_process_video(struct sur40_state *sur40) +{ + + struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer); + int result, bulk_read, bufpos; + struct sur40_buffer *new_buf; + uint8_t *buffer; + + if (list_empty(&sur40->buf_list)) + return; + + /* get a new buffer from the list */ + spin_lock(&sur40->qlock); + new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list); + list_del(&new_buf->list); + spin_unlock(&sur40->qlock); + + /* retrieve data via bulk read */ + bufpos = 0; + + result = usb_bulk_msg(sur40->usbdev, + usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), + sur40->bulk_in_buffer, sur40->bulk_in_size, + &bulk_read, 1000); + + if (result < 0) { + dev_err(sur40->dev, "error in usb_bulk_read\n"); + goto err_poll; + } + + if (bulk_read != sizeof(struct sur40_image_header)) { + dev_err(sur40->dev, "received %d bytes (%ld expected)\n", + bulk_read, sizeof(struct sur40_image_header)); + goto err_poll; + } + + if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) { + dev_err(sur40->dev, "image magic mismatch\n"); + goto err_poll; + } + + if (le32_to_cpu(img->size) != sur40_video_format.sizeimage) { + dev_err(sur40->dev, "image size mismatch\n"); + goto err_poll; + } + + buffer = vb2_plane_vaddr(&new_buf->vb, 0); + while (bufpos < sur40_video_format.sizeimage) { + result = usb_bulk_msg(sur40->usbdev, + usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), + buffer+bufpos, VIDEO_PACKET_SIZE, + &bulk_read, 1000); + if (result < 0) { + dev_err(sur40->dev, "error in usb_bulk_read\n"); + goto err_poll; + } + bufpos += bulk_read; + } + + /* mark as finished */ + v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp); + new_buf->vb.v4l2_buf.sequence = sur40->sequence++; + new_buf->vb.v4l2_buf.field = V4L2_FIELD_NONE; + vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE); + return; + +err_poll: + vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_ERROR); } /* Initialize input device parameters. */ @@ -377,6 +497,11 @@ static int sur40_probe(struct usb_interface *interface, goto err_free_dev; } + /* initialize locks/lists */ + INIT_LIST_HEAD(&sur40->buf_list); + spin_lock_init(&sur40->qlock); + mutex_init(&sur40->lock); + /* Set up polled input device control structure */ poll_dev->private = sur40; poll_dev->poll_interval = POLL_INTERVAL; @@ -387,7 +512,7 @@ static int sur40_probe(struct usb_interface *interface, /* Set up regular input device structure */ sur40_input_setup(poll_dev->input); - poll_dev->input->name = "Samsung SUR40"; + poll_dev->input->name = DRIVER_LONG; usb_to_input_id(usbdev, &poll_dev->input->id); usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys)); strlcat(sur40->phys, "/input0", sizeof(sur40->phys)); @@ -408,6 +533,7 @@ static int sur40_probe(struct usb_interface *interface, goto err_free_polldev; } + /* register the polled input device */ error = input_register_polled_device(poll_dev); if (error) { dev_err(&interface->dev, @@ -415,12 +541,54 @@ static int sur40_probe(struct usb_interface *interface, goto err_free_buffer; } + /* register the video master device */ + snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG); + error = v4l2_device_register(sur40->dev, &sur40->v4l2); + if (error) { + dev_err(&interface->dev, + "Unable to register video master device."); + goto err_unreg_v4l2; + } + + /* initialize the lock and subdevice */ + sur40->queue = sur40_queue; + sur40->queue.drv_priv = sur40; + sur40->queue.lock = &sur40->lock; + + /* initialize the queue */ + error = vb2_queue_init(&sur40->queue); + if (error) + goto err_unreg_v4l2; + + sur40->alloc_ctx = vb2_dma_contig_init_ctx(sur40->dev); + if (IS_ERR(sur40->alloc_ctx)) { + dev_err(sur40->dev, "Can't allocate buffer context"); + goto err_unreg_v4l2; + } + + sur40->vdev = sur40_video_device; + sur40->vdev.v4l2_dev = &sur40->v4l2; + sur40->vdev.lock = &sur40->lock; + sur40->vdev.queue = &sur40->queue; + video_set_drvdata(&sur40->vdev, sur40); + + error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1); + if (error) { + dev_err(&interface->dev, + "Unable to register video subdevice."); + goto err_unreg_video; + } + /* we can register the device now, as it is ready */ usb_set_intfdata(interface, sur40); dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC); return 0; +err_unreg_video: + video_unregister_device(&sur40->vdev); +err_unreg_v4l2: + v4l2_device_unregister(&sur40->v4l2); err_free_buffer: kfree(sur40->bulk_in_buffer); err_free_polldev: @@ -436,6 +604,10 @@ static void sur40_disconnect(struct usb_interface *interface) { struct sur40_state *sur40 = usb_get_intfdata(interface); + v4l2_device_unregister(&sur40->v4l2); + video_unregister_device(&sur40->vdev); + vb2_dma_contig_cleanup_ctx(sur40->alloc_ctx); + input_unregister_polled_device(sur40->input); input_free_polled_device(sur40->input); kfree(sur40->bulk_in_buffer); @@ -445,12 +617,239 @@ static void sur40_disconnect(struct usb_interface *interface) dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC); } +/* + * Setup the constraints of the queue: besides setting the number of planes + * per buffer and the size and allocation context of each plane, it also + * checks if sufficient buffers have been allocated. Usually 3 is a good + * minimum number: many DMA engines need a minimum of 2 buffers in the + * queue and you need to have another available for userspace processing. + */ +static int sur40_queue_setup(struct vb2_queue *q, const struct v4l2_format *fmt, + unsigned int *nbuffers, unsigned int *nplanes, + unsigned int sizes[], void *alloc_ctxs[]) +{ + struct sur40_state *sur40 = vb2_get_drv_priv(q); + + if (q->num_buffers + *nbuffers < 3) + *nbuffers = 3 - q->num_buffers; + + if (fmt && fmt->fmt.pix.sizeimage < sur40_video_format.sizeimage) + return -EINVAL; + + *nplanes = 1; + sizes[0] = fmt ? fmt->fmt.pix.sizeimage : sur40_video_format.sizeimage; + alloc_ctxs[0] = sur40->alloc_ctx; + + return 0; +} + +/* + * Prepare the buffer for queueing to the DMA engine: check and set the + * payload size. + */ +static int sur40_buffer_prepare(struct vb2_buffer *vb) +{ + struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); + unsigned long size = sur40_video_format.sizeimage; + + if (vb2_plane_size(vb, 0) < size) { + dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n", + vb2_plane_size(vb, 0), size); + return -EINVAL; + } + + vb2_set_plane_payload(vb, 0, size); + return 0; +} + +/* + * Queue this buffer to the DMA engine. + */ +static void sur40_buffer_queue(struct vb2_buffer *vb) +{ + struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); + struct sur40_buffer *buf = (struct sur40_buffer *)vb; + + spin_lock(&sur40->qlock); + list_add_tail(&buf->list, &sur40->buf_list); + spin_unlock(&sur40->qlock); +} + +static void return_all_buffers(struct sur40_state *sur40, + enum vb2_buffer_state state) +{ + struct sur40_buffer *buf, *node; + + spin_lock(&sur40->qlock); + list_for_each_entry_safe(buf, node, &sur40->buf_list, list) { + vb2_buffer_done(&buf->vb, state); + list_del(&buf->list); + } + spin_unlock(&sur40->qlock); +} + +/* + * Start streaming. First check if the minimum number of buffers have been + * queued. If not, then return -ENOBUFS and the vb2 framework will call + * this function again the next time a buffer has been queued until enough + * buffers are available to actually start the DMA engine. + */ +static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count) +{ + struct sur40_state *sur40 = vb2_get_drv_priv(vq); + + sur40->sequence = 0; + return 0; +} + +/* + * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued + * and passed on to the vb2 framework marked as STATE_ERROR. + */ +static void sur40_stop_streaming(struct vb2_queue *vq) +{ + struct sur40_state *sur40 = vb2_get_drv_priv(vq); + /* Release all active buffers */ + return_all_buffers(sur40, VB2_BUF_STATE_ERROR); +} + +/* V4L ioctl */ +static int sur40_vidioc_querycap(struct file *file, void *priv, + struct v4l2_capability *cap) +{ + struct sur40_state *sur40 = video_drvdata(file); + + strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver)); + strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card)); + usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info)); + cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | + V4L2_CAP_READWRITE | + V4L2_CAP_STREAMING; + cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS; + return 0; +} + +static int sur40_vidioc_enum_input(struct file *file, void *priv, + struct v4l2_input *i) +{ + if (i->index != 0) + return -EINVAL; + i->type = V4L2_INPUT_TYPE_CAMERA; + i->std = V4L2_STD_UNKNOWN; + strlcpy(i->name, "In-Cell Sensor", sizeof(i->name)); + i->capabilities = 0; + return 0; +} + +static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i) +{ + return (i == 0) ? 0 : -EINVAL; +} + +static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i) +{ + *i = 0; + return 0; +} + +static int sur40_vidioc_fmt(struct file *file, void *priv, + struct v4l2_format *f) +{ + f->fmt.pix = sur40_video_format; + return 0; +} + +static int sur40_vidioc_enum_fmt(struct file *file, void *priv, + struct v4l2_fmtdesc *f) +{ + if (f->index != 0) + return -EINVAL; + strlcpy(f->description, "8-bit greyscale", sizeof(f->description)); + f->pixelformat = V4L2_PIX_FMT_GREY; + f->flags = 0; + return 0; +} + static const struct usb_device_id sur40_table[] = { { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */ { } /* terminating null entry */ }; MODULE_DEVICE_TABLE(usb, sur40_table); +/* V4L2 structures */ +static struct vb2_ops sur40_queue_ops = { + .queue_setup = sur40_queue_setup, + .buf_prepare = sur40_buffer_prepare, + .buf_queue = sur40_buffer_queue, + .start_streaming = sur40_start_streaming, + .stop_streaming = sur40_stop_streaming, + .wait_prepare = vb2_ops_wait_prepare, + .wait_finish = vb2_ops_wait_finish, +}; + +static struct vb2_queue sur40_queue = { + .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, + .io_modes = VB2_MMAP | VB2_READ, + .buf_struct_size = sizeof(struct sur40_buffer), + .ops = &sur40_queue_ops, + .mem_ops = &vb2_dma_contig_memops, + .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC, + .min_buffers_needed = 3, + .gfp_flags = GFP_DMA, +}; + +static const struct v4l2_file_operations sur40_video_fops = { + .owner = THIS_MODULE, + .open = v4l2_fh_open, + .release = vb2_fop_release, + .unlocked_ioctl = video_ioctl2, + .read = vb2_fop_read, + .mmap = vb2_fop_mmap, + .poll = vb2_fop_poll, +}; + +static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = { + + .vidioc_querycap = sur40_vidioc_querycap, + + .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt, + .vidioc_try_fmt_vid_cap = sur40_vidioc_fmt, + .vidioc_s_fmt_vid_cap = sur40_vidioc_fmt, + .vidioc_g_fmt_vid_cap = sur40_vidioc_fmt, + + .vidioc_enum_input = sur40_vidioc_enum_input, + .vidioc_g_input = sur40_vidioc_g_input, + .vidioc_s_input = sur40_vidioc_s_input, + + .vidioc_reqbufs = vb2_ioctl_reqbufs, + .vidioc_create_bufs = vb2_ioctl_create_bufs, + .vidioc_querybuf = vb2_ioctl_querybuf, + .vidioc_qbuf = vb2_ioctl_qbuf, + .vidioc_dqbuf = vb2_ioctl_dqbuf, + .vidioc_expbuf = vb2_ioctl_expbuf, + + .vidioc_streamon = vb2_ioctl_streamon, + .vidioc_streamoff = vb2_ioctl_streamoff, +}; + +static struct video_device sur40_video_device = { + .name = DRIVER_LONG, + .fops = &sur40_video_fops, + .ioctl_ops = &sur40_video_ioctl_ops, + .release = video_device_release_empty, +}; + +static struct v4l2_pix_format sur40_video_format = { + .pixelformat = V4L2_PIX_FMT_GREY, + .width = SENSOR_RES_X / 2, + .height = SENSOR_RES_Y / 2, + .field = V4L2_FIELD_NONE, + .colorspace = V4L2_COLORSPACE_SRGB, + .bytesperline = SENSOR_RES_X / 2, + .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2), + .priv = 0, +}; + /* USB-specific object needed to register this driver with the USB subsystem. */ static struct usb_driver sur40_driver = { .name = DRIVER_SHORT, -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
