[media] pwc: Get rid of error_status and unplugged variables

Having 2 ways of tracking disconnection is too much, remove both and
instead simply set pdev->udev to NULL on disconnect. Also check for
pdev->udev being NULL in all possible entry paths.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/pwc/pwc-if.c

@@ -570,14 +570,7 @@ static void pwc_isoc_cleanup(struct pwc_device *pdev)
 
 	pwc_iso_stop(pdev);
 	pwc_iso_free(pdev);
-
-	/* Stop camera, but only if we are sure the camera is still there (unplug
-	   is signalled by EPIPE)
-	 */
-	if (pdev->error_status != EPIPE) {
-		PWC_DEBUG_OPEN("Setting alternate interface 0.\n");
-		usb_set_interface(pdev->udev, 0, 0);
-	}
+	usb_set_interface(pdev->udev, 0, 0);
 
 	pdev->iso_init = 0;
 	PWC_DEBUG_OPEN("<< pwc_isoc_cleanup()\n");
@@ -719,6 +712,9 @@ static int pwc_video_open(struct file *file)
 	PWC_DEBUG_OPEN(">> video_open called(vdev = 0x%p).\n", vdev);
 
 	pdev = video_get_drvdata(vdev);
+	if (!pdev->udev)
+		return -ENODEV;
+
 	if (pdev->vopen) {
 		PWC_DEBUG_OPEN("I'm busy, someone is using the device.\n");
 		return -EBUSY;
@@ -760,7 +756,6 @@ static int pwc_video_open(struct file *file)
 
 	/* Reset buffers & parameters */
 	pdev->visoc_errors = 0;
-	pdev->error_status = 0;
 	pwc_construct(pdev); /* set min/max sizes correct */
 
 	/* Set some defaults */
@@ -837,7 +832,7 @@ static int pwc_video_close(struct file *file)
 	pwc_free_buffers(pdev);
 
 	/* Turn off LEDS and power down camera, but only when not unplugged */
-	if (!pdev->unplugged) {
+	if (pdev->udev) {
 		/* Turn LEDs off */
 		if (pwc_set_leds(pdev, 0, 0) < 0)
 			PWC_DEBUG_MODULE("Failed to set LED on/off time.\n");
@@ -859,8 +854,8 @@ static ssize_t pwc_video_read(struct file *file, char __user *buf,
 	struct video_device *vdev = file->private_data;
 	struct pwc_device *pdev = video_get_drvdata(vdev);
 
-	if (pdev->error_status)
-		return -pdev->error_status;
+	if (!pdev->udev)
+		return -ENODEV;
 
 	return vb2_read(&pdev->vb_queue, buf, count, ppos,
 			file->f_flags & O_NONBLOCK);
@@ -871,7 +866,7 @@ static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
 	struct video_device *vdev = file->private_data;
 	struct pwc_device *pdev = video_get_drvdata(vdev);
 
-	if (pdev->error_status)
+	if (!pdev->udev)
 		return POLL_ERR;
 
 	return vb2_poll(&pdev->vb_queue, file, wait);
@@ -923,8 +918,8 @@ static int buffer_prepare(struct vb2_buffer *vb)
 	struct pwc_device *pdev = vb2_get_drv_priv(vb->vb2_queue);
 
 	/* Don't allow queing new buffers after device disconnection */
-	if (pdev->error_status)
-		return -pdev->error_status;
+	if (!pdev->udev)
+		return -ENODEV;
 
 	return 0;
 }
@@ -964,14 +959,18 @@ static int start_streaming(struct vb2_queue *vq)
 {
 	struct pwc_device *pdev = vb2_get_drv_priv(vq);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	return pwc_isoc_init(pdev);
 }
 
 static int stop_streaming(struct vb2_queue *vq)
 {
 	struct pwc_device *pdev = vb2_get_drv_priv(vq);
 
-	pwc_isoc_cleanup(pdev);
+	if (pdev->udev)
+		pwc_isoc_cleanup(pdev);
 	pwc_cleanup_queued_bufs(pdev);
 
 	return 0;
@@ -1389,15 +1388,12 @@ static void usb_pwc_disconnect(struct usb_interface *intf)
 	struct pwc_device *pdev  = usb_get_intfdata(intf);
 
 	mutex_lock(&pdev->modlock);
-	usb_set_intfdata (intf, NULL);
-
-	/* We got unplugged; this is signalled by an EPIPE error code */
-	pdev->error_status = EPIPE;
-	pdev->unplugged = 1;
 
+	usb_set_intfdata(intf, NULL);
 	/* No need to keep the urbs around after disconnection */
 	pwc_isoc_cleanup(pdev);
 	pwc_cleanup_queued_bufs(pdev);
+	pdev->udev = NULL;
 
 	mutex_unlock(&pdev->modlock);
 

drivers/media/video/pwc/pwc-v4l.c

@@ -288,6 +288,9 @@ static int pwc_vidioc_set_fmt(struct pwc_device *pdev, struct v4l2_format *f)
 {
 	int ret, fps, snapshot, compression, pixelformat;
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	ret = pwc_vidioc_try_fmt(pdev, f);
 	if (ret<0)
 		return ret;
@@ -346,6 +349,9 @@ static int pwc_querycap(struct file *file, void *fh, struct v4l2_capability *cap
 	struct video_device *vdev = video_devdata(file);
 	struct pwc_device *pdev = video_drvdata(file);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	strcpy(cap->driver, PWC_NAME);
 	strlcpy(cap->card, vdev->name, sizeof(cap->card));
 	usb_make_path(pdev->udev, cap->bus_info, sizeof(cap->bus_info));
@@ -414,6 +420,9 @@ static int pwc_g_ctrl(struct file *file, void *fh, struct v4l2_control *c)
 	struct pwc_device *pdev = video_drvdata(file);
 	int ret;
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	switch (c->id) {
 	case V4L2_CID_BRIGHTNESS:
 		c->value = pwc_get_brightness(pdev);
@@ -517,6 +526,9 @@ static int pwc_s_ctrl(struct file *file, void *fh, struct v4l2_control *c)
 	struct pwc_device *pdev = video_drvdata(file);
 	int ret;
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	switch (c->id) {
 	case V4L2_CID_BRIGHTNESS:
 		c->value <<= 9;
@@ -692,27 +704,39 @@ static int pwc_qbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 {
 	struct pwc_device *pdev = video_drvdata(file);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	return vb2_qbuf(&pdev->vb_queue, buf);
 }
 
 static int pwc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 {
 	struct pwc_device *pdev = video_drvdata(file);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	return vb2_dqbuf(&pdev->vb_queue, buf, file->f_flags & O_NONBLOCK);
 }
 
 static int pwc_streamon(struct file *file, void *fh, enum v4l2_buf_type i)
 {
 	struct pwc_device *pdev = video_drvdata(file);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	return vb2_streamon(&pdev->vb_queue, i);
 }
 
 static int pwc_streamoff(struct file *file, void *fh, enum v4l2_buf_type i)
 {
 	struct pwc_device *pdev = video_drvdata(file);
 
+	if (!pdev->udev)
+		return -ENODEV;
+
 	return vb2_streamoff(&pdev->vb_queue, i);
 }
 

drivers/media/video/pwc/pwc.h

@@ -161,7 +161,6 @@ struct pwc_device
 	int release;		/* release number */
 	int features;		/* feature bits */
 	char serial[30];	/* serial number (string) */
-	int error_status;	/* set when something goes wrong */
 	int usb_init;		/* set when the cam has been initialized */
 
 	/*** Video data ***/
@@ -180,7 +179,6 @@ struct pwc_device
 	char vsnapshot;		/* snapshot mode */
 	char vsync;		/* used by isoc handler */
 	char vmirror;		/* for ToUCaM series */
-	char unplugged;
 
 	int cmd_len;
 	unsigned char cmd_buf[13];