V4L/DVB (11220): gspca - finepix: Use a workqueue for streaming.

Tested-by: Frank Zago <frank@zago.net>
Acked-by: Frank Zago <frank@zago.net>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 134 insertions, 287 deletions

diff --git a/drivers/media/video/gspca/finepix.c b/drivers/media/video/gspca/finepix.c
index dc65c363aa87..00e6863ed666 100644
--- a/drivers/media/video/gspca/finepix.c
+++ b/drivers/media/video/gspca/finepix.c
@@ -27,7 +27,7 @@ MODULE_DESCRIPTION("Fujifilm FinePix USB V4L2 driver");
 MODULE_LICENSE("GPL");
 
 /* Default timeout, in ms */
-#define FPIX_TIMEOUT (HZ / 10)
+#define FPIX_TIMEOUT 250
 
 /* Maximum transfer size to use. The windows driver reads by chunks of
  * 0x2000 bytes, so do the same. Note: reading more seems to work
@@ -38,38 +38,15 @@ MODULE_LICENSE("GPL");
 struct usb_fpix {
         struct gspca_dev gspca_dev;     /* !! must be the first item */
 
-        /*
-         * USB stuff
-         */
-        struct usb_ctrlrequest ctrlreq;
-        struct urb *control_urb;
-        struct timer_list bulk_timer;
-
-        enum {
-                FPIX_NOP,       /* inactive, else streaming */
-                FPIX_RESET,     /* must reset */
-                FPIX_REQ_FRAME, /* requesting a frame */
-                FPIX_READ_FRAME,        /* reading frame */
-        } state;
-
-        /*
-         * Driver stuff
-         */
-        struct delayed_work wqe;
-        struct completion can_close;
-        int streaming;
+        struct work_struct work_struct;
+        struct workqueue_struct *work_thread;
 };
 
 /* Delay after which claim the next frame. If the delay is too small,
  * the camera will return old frames. On the 4800Z, 20ms is bad, 25ms
- * will fail every 4 or 5 frames, but 30ms is perfect. */
-#define NEXT_FRAME_DELAY  (((HZ * 30) + 999) / 1000)
-
-#define dev_new_state(new_state) {                              \
-                PDEBUG(D_STREAM, "new state from %d to %d at %s:%d",    \
-                        dev->state, new_state, __func__, __LINE__);     \
-                dev->state = new_state;                                 \
-}
+ * will fail every 4 or 5 frames, but 30ms is perfect. On the A210,
+ * 30ms is bad while 35ms is perfect. */
+#define NEXT_FRAME_DELAY 35
 
 /* These cameras only support 320x200. */
 static const struct v4l2_pix_format fpix_mode[1] = {
@@ -80,314 +57,183 @@ static const struct v4l2_pix_format fpix_mode[1] = {
                 .priv = 0}
 };
 
-/* Reads part of a frame */
-static void read_frame_part(struct usb_fpix *dev)
+/* send a command to the webcam */
+static int command(struct gspca_dev *gspca_dev,
+                int order)      /* 0: reset, 1: frame request */
 {
-        int ret;
+        static u8 order_values[2][12] = {
+                {0xc6, 0, 0, 0, 0, 0, 0,    0, 0x20, 0, 0, 0},  /* reset */
+                {0xd3, 0, 0, 0, 0, 0, 0, 0x01,    0, 0, 0, 0},  /* fr req */
+        };
 
-        PDEBUG(D_STREAM, "read_frame_part");
-
-        /* Reads part of a frame */
-        ret = usb_submit_urb(dev->gspca_dev.urb[0], GFP_ATOMIC);
-        if (ret) {
-                dev_new_state(FPIX_RESET);
-                schedule_delayed_work(&dev->wqe, 1);
-                PDEBUG(D_STREAM, "usb_submit_urb failed with %d",
-                        ret);
-        } else {
-                /* Sometimes we never get a callback, so use a timer.
-                 * Is this masking a bug somewhere else? */
-                dev->bulk_timer.expires = jiffies + msecs_to_jiffies(150);
-                add_timer(&dev->bulk_timer);
-        }
+        memcpy(gspca_dev->usb_buf, order_values[order], 12);
+        return usb_control_msg(gspca_dev->dev,
+                        usb_sndctrlpipe(gspca_dev->dev, 0),
+                        USB_REQ_GET_STATUS,
+                        USB_DIR_OUT | USB_TYPE_CLASS |
+                        USB_RECIP_INTERFACE, 0, 0, gspca_dev->usb_buf,
+                        12, FPIX_TIMEOUT);
 }
 
-/* Callback for URBs. */
-static void urb_callback(struct urb *urb)
+/* workqueue */
+static void dostream(struct work_struct *work)
 {
-        struct gspca_dev *gspca_dev = urb->context;
-        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
-
-        PDEBUG(D_PACK,
-                "enter urb_callback - status=%d, length=%d",
-                urb->status, urb->actual_length);
-
-        if (dev->state == FPIX_READ_FRAME)
-                del_timer(&dev->bulk_timer);
-
-        if (urb->status != 0) {
-                /* We kill a stuck urb every 50 frames on average, so don't
-                 * display a log message for that. */
-                if (urb->status != -ECONNRESET)
-                        PDEBUG(D_STREAM, "bad URB status %d", urb->status);
-                dev_new_state(FPIX_RESET);
-                schedule_delayed_work(&dev->wqe, 1);
-        }
-
-        switch (dev->state) {
-        case FPIX_REQ_FRAME:
-                dev_new_state(FPIX_READ_FRAME);
-                read_frame_part(dev);
-                break;
-
-        case FPIX_READ_FRAME: {
-                unsigned char *data = urb->transfer_buffer;
-                struct gspca_frame *frame;
-
-                frame = gspca_get_i_frame(&dev->gspca_dev);
-                if (frame == NULL)
-                        gspca_dev->last_packet_type = DISCARD_PACKET;
-                if (urb->actual_length < FPIX_MAX_TRANSFER ||
-                        (data[urb->actual_length-2] == 0xff &&
-                                data[urb->actual_length-1] == 0xd9)) {
-
-                        /* If the result is less than what was asked
-                         * for, then it's the end of the
-                         * frame. Sometime the jpeg is not complete,
-                         * but there's nothing we can do. We also end
-                         * here if the the jpeg ends right at the end
-                         * of the frame. */
-                        if (frame)
-                                gspca_frame_add(gspca_dev, LAST_PACKET,
-                                                frame,
-                                                data, urb->actual_length);
-                        dev_new_state(FPIX_REQ_FRAME);
-                        schedule_delayed_work(&dev->wqe, NEXT_FRAME_DELAY);
-                } else {
+        struct usb_fpix *dev = container_of(work, struct usb_fpix, work_struct);
+        struct gspca_dev *gspca_dev = &dev->gspca_dev;
+        struct urb *urb = gspca_dev->urb[0];
+        u8 *data = urb->transfer_buffer;
+        struct gspca_frame *frame;
+        int ret = 0;
+        int len;
+
+        /* synchronize with the main driver */
+        mutex_lock(&gspca_dev->usb_lock);
+        mutex_unlock(&gspca_dev->usb_lock);
+        PDEBUG(D_STREAM, "dostream started");
+
+        /* loop reading a frame */
+again:
+        while (gspca_dev->present && gspca_dev->streaming) {
+
+                /* request a frame */
+                mutex_lock(&gspca_dev->usb_lock);
+                ret = command(gspca_dev, 1);
+                mutex_unlock(&gspca_dev->usb_lock);
+                if (ret < 0)
+                        break;
+                if (!gspca_dev->present || !gspca_dev->streaming)
+                        break;
+
+                /* the frame comes in parts */
+                for (;;) {
+                        ret = usb_bulk_msg(gspca_dev->dev,
+                                        urb->pipe,
+                                        data,
+                                        FPIX_MAX_TRANSFER,
+                                        &len, FPIX_TIMEOUT);
+                        if (ret < 0) {
+                                /* Most of the time we get a timeout
+                                 * error. Just restart. */
+                                goto again;
+                        }
+                        if (!gspca_dev->present || !gspca_dev->streaming)
+                                goto out;
+                        frame = gspca_get_i_frame(&dev->gspca_dev);
+                        if (frame == NULL)
+                                gspca_dev->last_packet_type = DISCARD_PACKET;
+
+                        if (len < FPIX_MAX_TRANSFER ||
+                                (data[len - 2] == 0xff &&
+                                        data[len - 1] == 0xd9)) {
+
+                                /* If the result is less than what was asked
+                                 * for, then it's the end of the
+                                 * frame. Sometimes the jpeg is not complete,
+                                 * but there's nothing we can do. We also end
+                                 * here if the the jpeg ends right at the end
+                                 * of the frame. */
+                                if (frame)
+                                        frame = gspca_frame_add(gspca_dev,
+                                                        LAST_PACKET,
+                                                        frame,
+                                                        data, len);
+                                break;
+                        }
 
                         /* got a partial image */
                         if (frame)
                                 gspca_frame_add(gspca_dev,
                                                 gspca_dev->last_packet_type
-                                                                == LAST_PACKET
+                                                        == LAST_PACKET
                                                 ? FIRST_PACKET : INTER_PACKET,
-                                                frame,
-                                        data, urb->actual_length);
-                        read_frame_part(dev);
+                                                frame, data, len);
                 }
-                break;
-            }
-
-        case FPIX_NOP:
-        case FPIX_RESET:
-                PDEBUG(D_STREAM, "invalid state %d", dev->state);
-                break;
-        }
-}
-
-/* Request a new frame */
-static void request_frame(struct usb_fpix *dev)
-{
-        int ret;
-        struct gspca_dev *gspca_dev = &dev->gspca_dev;
 
-        /* Setup command packet */
-        memset(gspca_dev->usb_buf, 0, 12);
-        gspca_dev->usb_buf[0] = 0xd3;
-        gspca_dev->usb_buf[7] = 0x01;
-
-        /* Request a frame */
-        dev->ctrlreq.bRequestType =
-                USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
-        dev->ctrlreq.bRequest = USB_REQ_GET_STATUS;
-        dev->ctrlreq.wValue = 0;
-        dev->ctrlreq.wIndex = 0;
-        dev->ctrlreq.wLength = cpu_to_le16(12);
-
-        usb_fill_control_urb(dev->control_urb,
-                             gspca_dev->dev,
-                             usb_sndctrlpipe(gspca_dev->dev, 0),
-                             (unsigned char *) &dev->ctrlreq,
-                             gspca_dev->usb_buf,
-                             12, urb_callback, gspca_dev);
-
-        ret = usb_submit_urb(dev->control_urb, GFP_ATOMIC);
-        if (ret) {
-                dev_new_state(FPIX_RESET);
-                schedule_delayed_work(&dev->wqe, 1);
-                PDEBUG(D_STREAM, "usb_submit_urb failed with %d", ret);
+                /* We must wait before trying reading the next
+                 * frame. If we don't, or if the delay is too short,
+                 * the camera will disconnect. */
+                msleep(NEXT_FRAME_DELAY);
         }
-}
-
-/*--------------------------------------------------------------------------*/
 
-/* State machine. */
-static void fpix_sm(struct work_struct *work)
-{
-        struct usb_fpix *dev = container_of(work, struct usb_fpix, wqe.work);
-
-        PDEBUG(D_STREAM, "fpix_sm state %d", dev->state);
-
-        /* verify that the device wasn't unplugged */
-        if (!dev->gspca_dev.present) {
-                PDEBUG(D_STREAM, "device is gone");
-                dev_new_state(FPIX_NOP);
-                complete(&dev->can_close);
-                return;
-        }
-
-        if (!dev->streaming) {
-                PDEBUG(D_STREAM, "stopping state machine");
-                dev_new_state(FPIX_NOP);
-                complete(&dev->can_close);
-                return;
-        }
-
-        switch (dev->state) {
-        case FPIX_RESET:
-                dev_new_state(FPIX_REQ_FRAME);
-                schedule_delayed_work(&dev->wqe, HZ / 10);
-                break;
-
-        case FPIX_REQ_FRAME:
-                /* get an image */
-                request_frame(dev);
-                break;
-
-        case FPIX_NOP:
-        case FPIX_READ_FRAME:
-                PDEBUG(D_STREAM, "invalid state %d", dev->state);
-                break;
-        }
+out:
+        PDEBUG(D_STREAM, "dostream stopped");
 }
 
 /* this function is called at probe time */
 static int sd_config(struct gspca_dev *gspca_dev,
                 const struct usb_device_id *id)
 {
+        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
         struct cam *cam = &gspca_dev->cam;
 
         cam->cam_mode = fpix_mode;
         cam->nmodes = 1;
         cam->bulk_size = FPIX_MAX_TRANSFER;
 
-/*      gspca_dev->nbalt = 1;    * use bulk transfer */
-        return 0;
-}
-
-/* Stop streaming and free the ressources allocated by sd_start. */
-static void sd_stopN(struct gspca_dev *gspca_dev)
-{
-        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
+        INIT_WORK(&dev->work_struct, dostream);
 
-        dev->streaming = 0;
-
-        /* Stop the state machine */
-        if (dev->state != FPIX_NOP)
-                wait_for_completion(&dev->can_close);
-}
-
-/* called on streamoff with alt 0 and disconnect */
-static void sd_stop0(struct gspca_dev *gspca_dev)
-{
-        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
-
-        usb_free_urb(dev->control_urb);
-        dev->control_urb = NULL;
-}
-
-/* Kill an URB that hasn't completed. */
-static void timeout_kill(unsigned long data)
-{
-        struct urb *urb = (struct urb *) data;
-
-        usb_unlink_urb(urb);
+        return 0;
 }
 
 /* this function is called at probe and resume time */
 static int sd_init(struct gspca_dev *gspca_dev)
 {
-        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
-
-        INIT_DELAYED_WORK(&dev->wqe, fpix_sm);
-
-        init_timer(&dev->bulk_timer);
-        dev->bulk_timer.function = timeout_kill;
-
         return 0;
 }
 
+/* start the camera */
 static int sd_start(struct gspca_dev *gspca_dev)
 {
         struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
-        int ret;
-        int size_ret;
+        int ret, len;
 
         /* Init the device */
-        memset(gspca_dev->usb_buf, 0, 12);
-        gspca_dev->usb_buf[0] = 0xc6;
-        gspca_dev->usb_buf[8] = 0x20;
-
-        ret = usb_control_msg(gspca_dev->dev,
-                        usb_sndctrlpipe(gspca_dev->dev, 0),
-                        USB_REQ_GET_STATUS,
-                        USB_DIR_OUT | USB_TYPE_CLASS |
-                        USB_RECIP_INTERFACE, 0, 0, gspca_dev->usb_buf,
-                        12, FPIX_TIMEOUT);
-
-        if (ret != 12) {
-                PDEBUG(D_STREAM, "usb_control_msg failed (%d)", ret);
-                ret = -EIO;
-                goto error;
+        ret = command(gspca_dev, 0);
+        if (ret < 0) {
+                PDEBUG(D_STREAM, "init failed %d", ret);
+                return ret;
         }
 
         /* Read the result of the command. Ignore the result, for it
          * varies with the device. */
         ret = usb_bulk_msg(gspca_dev->dev,
                         gspca_dev->urb[0]->pipe,
-                        gspca_dev->usb_buf, FPIX_MAX_TRANSFER, &size_ret,
+                        gspca_dev->urb[0]->transfer_buffer,
+                        FPIX_MAX_TRANSFER, &len,
                         FPIX_TIMEOUT);
-        if (ret != 0) {
-                PDEBUG(D_STREAM, "usb_bulk_msg failed (%d)", ret);
-                ret = -EIO;
-                goto error;
+        if (ret < 0) {
+                PDEBUG(D_STREAM, "usb_bulk_msg failed %d", ret);
+                return ret;
         }
 
         /* Request a frame, but don't read it */
-        memset(gspca_dev->usb_buf, 0, 12);
-        gspca_dev->usb_buf[0] = 0xd3;
-        gspca_dev->usb_buf[7] = 0x01;
-
-        ret = usb_control_msg(gspca_dev->dev,
-                        usb_sndctrlpipe(gspca_dev->dev, 0),
-                        USB_REQ_GET_STATUS,
-                        USB_DIR_OUT | USB_TYPE_CLASS |
-                        USB_RECIP_INTERFACE, 0, 0, gspca_dev->usb_buf,
-                        12, FPIX_TIMEOUT);
-        if (ret != 12) {
-                PDEBUG(D_STREAM, "usb_control_msg failed (%d)", ret);
-                ret = -EIO;
-                goto error;
+        ret = command(gspca_dev, 1);
+        if (ret < 0) {
+                PDEBUG(D_STREAM, "frame request failed %d", ret);
+                return ret;
         }
 
         /* Again, reset bulk in endpoint */
         usb_clear_halt(gspca_dev->dev, gspca_dev->urb[0]->pipe);
 
-        /* Allocate a control URB */
-        dev->control_urb = usb_alloc_urb(0, GFP_KERNEL);
-        if (!dev->control_urb) {
-                PDEBUG(D_STREAM, "No free urbs available");
-                ret = -EIO;
-                goto error;
-        }
-
-        /* Various initializations. */
-        init_completion(&dev->can_close);
-        dev->bulk_timer.data = (unsigned long)dev->gspca_dev.urb[0];
-        dev->gspca_dev.urb[0]->complete = urb_callback;
-        dev->streaming = 1;
-
-        /* Schedule a frame request. */
-        dev_new_state(FPIX_REQ_FRAME);
-        schedule_delayed_work(&dev->wqe, 1);
+        /* Start the workqueue function to do the streaming */
+        dev->work_thread = create_singlethread_workqueue(MODULE_NAME);
+        queue_work(dev->work_thread, &dev->work_struct);
 
         return 0;
+}
+
+/* called on streamoff with alt==0 and on disconnect */
+/* the usb_lock is held at entry - restore on exit */
+static void sd_stop0(struct gspca_dev *gspca_dev)
+{
+        struct usb_fpix *dev = (struct usb_fpix *) gspca_dev;
 
-error:
-        /* Free the ressources */
-        sd_stopN(gspca_dev);
-        sd_stop0(gspca_dev);
-        return ret;
+        /* wait for the work queue to terminate */
+        mutex_unlock(&gspca_dev->usb_lock);
+        destroy_workqueue(dev->work_thread);
+        mutex_lock(&gspca_dev->usb_lock);
+        dev->work_thread = NULL;
 }
 
 /* Table of supported USB devices */
@@ -422,12 +268,11 @@ MODULE_DEVICE_TABLE(usb, device_table);
 
 /* sub-driver description */
 static const struct sd_desc sd_desc = {
-        .name = MODULE_NAME,
+        .name   = MODULE_NAME,
         .config = sd_config,
-        .init = sd_init,
-        .start = sd_start,
-        .stopN = sd_stopN,
-        .stop0 = sd_stop0,
+        .init   = sd_init,
+        .start  = sd_start,
+        .stop0  = sd_stop0,
 };
 
 /* -- device connect -- */
@@ -441,13 +286,13 @@ static int sd_probe(struct usb_interface *intf,
 }
 
 static struct usb_driver sd_driver = {
-        .name = MODULE_NAME,
-        .id_table = device_table,
-        .probe = sd_probe,
+        .name       = MODULE_NAME,
+        .id_table   = device_table,
+        .probe      = sd_probe,
         .disconnect = gspca_disconnect,
 #ifdef CONFIG_PM
         .suspend = gspca_suspend,
-        .resume = gspca_resume,
+        .resume  = gspca_resume,
 #endif
 };
 
@@ -455,12 +300,14 @@ static struct usb_driver sd_driver = {
 static int __init sd_mod_init(void)
 {
         int ret;
+
         ret = usb_register(&sd_driver);
         if (ret < 0)
                 return ret;
         PDEBUG(D_PROBE, "registered");
         return 0;
 }
+
 static void __exit sd_mod_exit(void)
 {
         usb_deregister(&sd_driver);