staging/easycap: kill telltale logic

This reason for this feature was

'some versions of the videodev module overwrite the data which has
been written by the call to usb_set_intfdata() in easycap_usb_probe(),
replacing it with a pointer to the embedded v4l2_device structure.
to detect this, the string in the easycap.telltale[] buffer is checked.'

The upstream version of v4l2_device_register sets driver data
only when it wasn't already set, therefore this is not needed

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Tomas Winkler 2011-07-05 21:07:47 +03:00 committed by Greg Kroah-Hartman
parent cbbd8a580e
commit cdaa898b5e
4 changed files with 3 additions and 122 deletions

View file

@ -280,8 +280,6 @@ struct inputset {
*/
/*---------------------------------------------------------------------------*/
struct easycap {
#define TELLTALE "expectedstring"
char telltale[16];
int isdongle;
int minor;

View file

@ -967,10 +967,6 @@ long easycap_unlocked_ioctl(struct file *file,
SAY("ERROR: peasycap is NULL\n");
return -1;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
p = peasycap->pusb_device;
if (!p) {
SAM("ERROR: peasycap->pusb_device is NULL\n");
@ -1004,12 +1000,6 @@ long easycap_unlocked_ioctl(struct file *file,
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
return -ERESTARTSYS;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
return -EFAULT;
}
p = peasycap->pusb_device;
if (!peasycap->pusb_device) {
SAM("ERROR: peasycap->pusb_device is NULL\n");
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);

View file

@ -158,10 +158,6 @@ static int easycap_open(struct inode *inode, struct file *file)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return -EFAULT;
}
if (!peasycap->pusb_device) {
SAM("ERROR: peasycap->pusb_device is NULL\n");
return -EFAULT;
@ -695,10 +691,6 @@ static int videodev_release(struct video_device *pvideo_device)
SAY("ending unsuccessfully\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return -EFAULT;
}
if (0 != kill_video_urbs(peasycap)) {
SAM("ERROR: kill_video_urbs() failed\n");
return -EFAULT;
@ -736,10 +728,6 @@ static void easycap_delete(struct kref *pkref)
SAM("ERROR: peasycap is NULL: cannot perform deletions\n");
return;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return;
}
kd = isdongle(peasycap);
/*---------------------------------------------------------------------------*/
/*
@ -962,10 +950,6 @@ static unsigned int easycap_poll(struct file *file, poll_table *wait)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return -EFAULT;
}
if (!peasycap->pusb_device) {
SAY("ERROR: peasycap->pusb_device is NULL\n");
return -EFAULT;
@ -996,11 +980,6 @@ static unsigned int easycap_poll(struct file *file, poll_table *wait)
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
return -ERESTARTSYS;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
return -ERESTARTSYS;
}
if (!peasycap->pusb_device) {
SAM("ERROR: peasycap->pusb_device is NULL\n");
mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
@ -2455,10 +2434,6 @@ static void easycap_vma_open(struct vm_area_struct *pvma)
SAY("ERROR: peasycap is NULL\n");
return;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return;
}
peasycap->vma_many++;
JOT(8, "%i=peasycap->vma_many\n", peasycap->vma_many);
return;
@ -2473,10 +2448,6 @@ static void easycap_vma_close(struct vm_area_struct *pvma)
SAY("ERROR: peasycap is NULL\n");
return;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return;
}
peasycap->vma_many--;
JOT(8, "%i=peasycap->vma_many\n", peasycap->vma_many);
return;
@ -2607,10 +2578,6 @@ static void easycap_complete(struct urb *purb)
SAY("ERROR: easycap_complete(): peasycap is NULL\n");
return;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return;
}
if (peasycap->video_eof)
return;
for (i = 0; i < VIDEO_ISOC_BUFFER_MANY; i++)
@ -3001,7 +2968,6 @@ static int easycap_usb_probe(struct usb_interface *intf,
struct easycap_format *peasycap_format;
int fmtidx;
struct inputset *inputset;
struct v4l2_device *pv4l2_device;
usbdev = interface_to_usbdev(intf);
@ -3055,7 +3021,6 @@ static int easycap_usb_probe(struct usb_interface *intf,
*/
/*---------------------------------------------------------------------------*/
peasycap->minor = -1;
strcpy(&peasycap->telltale[0], TELLTALE);
kref_init(&peasycap->kref);
JOM(8, "intf[%i]: after kref_init(..._video) "
"%i=peasycap->kref.refcount.counter\n",
@ -3268,23 +3233,6 @@ static int easycap_usb_probe(struct usb_interface *intf,
bInterfaceNumber);
return -ENODEV;
}
/*---------------------------------------------------------------------------*/
/*
* SOME VERSIONS OF THE videodev MODULE OVERWRITE THE DATA WHICH HAS
* BEEN WRITTEN BY THE CALL TO usb_set_intfdata() IN easycap_usb_probe(),
* REPLACING IT WITH A POINTER TO THE EMBEDDED v4l2_device STRUCTURE.
* TO DETECT THIS, THE STRING IN THE easycap.telltale[] BUFFER IS CHECKED.
*/
/*---------------------------------------------------------------------------*/
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
pv4l2_device = usb_get_intfdata(intf);
if (!pv4l2_device) {
SAY("ERROR: pv4l2_device is NULL\n");
return -ENODEV;
}
peasycap = (struct easycap *)
container_of(pv4l2_device, struct easycap, v4l2_device);
}
}
/*---------------------------------------------------------------------------*/
if ((USB_CLASS_VIDEO == bInterfaceClass) ||
@ -3776,14 +3724,12 @@ static int easycap_usb_probe(struct usb_interface *intf,
* THE VIDEO DEVICE CAN BE REGISTERED NOW, AS IT IS READY.
*/
/*--------------------------------------------------------------------------*/
if (0 != (v4l2_device_register(&(intf->dev),
&(peasycap->v4l2_device)))) {
if (v4l2_device_register(&intf->dev, &peasycap->v4l2_device)) {
SAM("v4l2_device_register() failed\n");
return -ENODEV;
} else {
JOM(4, "registered device instance: %s\n",
&(peasycap->v4l2_device.name[0]));
}
JOM(4, "registered device instance: %s\n",
peasycap->v4l2_device.name);
/*---------------------------------------------------------------------------*/
/*
* FIXME
@ -4160,7 +4106,6 @@ static void easycap_usb_disconnect(struct usb_interface *pusb_interface)
struct list_head *plist_head;
struct data_urb *pdata_urb;
int minor, m, kd;
struct v4l2_device *pv4l2_device;
JOT(4, "\n");
@ -4187,29 +4132,6 @@ static void easycap_usb_disconnect(struct usb_interface *pusb_interface)
return;
}
/*---------------------------------------------------------------------------*/
/*
* SOME VERSIONS OF THE videodev MODULE OVERWRITE THE DATA WHICH HAS
* BEEN WRITTEN BY THE CALL TO usb_set_intfdata() IN easycap_usb_probe(),
* REPLACING IT WITH A POINTER TO THE EMBEDDED v4l2_device STRUCTURE.
* TO DETECT THIS, THE STRING IN THE easycap.telltale[] BUFFER IS CHECKED.
*/
/*---------------------------------------------------------------------------*/
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
pv4l2_device = usb_get_intfdata(pusb_interface);
if (!pv4l2_device) {
SAY("ERROR: pv4l2_device is NULL\n");
return;
}
peasycap = (struct easycap *)
container_of(pv4l2_device, struct easycap, v4l2_device);
}
/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
/*---------------------------------------------------------------------------*/
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap: %p\n", peasycap);
return;
}
/*---------------------------------------------------------------------------*/
/*
* IF THE WAIT QUEUES ARE NOT CLEARED A DEADLOCK IS POSSIBLE. BEWARE.
*/

View file

@ -92,10 +92,6 @@ easycap_alsa_complete(struct urb *purb)
SAY("ERROR: peasycap is NULL\n");
return;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return;
}
much = 0;
if (peasycap->audio_idle) {
JOM(16, "%i=audio_idle %i=audio_isoc_streaming\n",
@ -310,10 +306,6 @@ static int easycap_alsa_open(struct snd_pcm_substream *pss)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
if (peasycap->psnd_card != psnd_card) {
SAM("ERROR: bad peasycap->psnd_card\n");
return -EFAULT;
@ -350,10 +342,6 @@ static int easycap_alsa_close(struct snd_pcm_substream *pss)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
pss->private_data = NULL;
peasycap->psubstream = NULL;
JOT(4, "ending successfully\n");
@ -441,10 +429,6 @@ static int easycap_alsa_prepare(struct snd_pcm_substream *pss)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
JOM(16, "ALSA decides %8i Hz=rate\n", pss->runtime->rate);
JOM(16, "ALSA decides %8ld =period_size\n", pss->runtime->period_size);
@ -488,11 +472,6 @@ static int easycap_alsa_trigger(struct snd_pcm_substream *pss, int cmd)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
switch (cmd) {
case SNDRV_PCM_TRIGGER_START: {
peasycap->audio_idle = 0;
@ -523,10 +502,6 @@ static snd_pcm_uframes_t easycap_alsa_pointer(struct snd_pcm_substream *pss)
SAY("ERROR: peasycap is NULL\n");
return -EFAULT;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
if ((0 != peasycap->audio_eof) || (0 != peasycap->audio_idle)) {
JOM(8, "returning -EIO because "
"%i=audio_idle %i=audio_eof\n",
@ -584,10 +559,6 @@ int easycap_alsa_probe(struct easycap *peasycap)
SAY("ERROR: peasycap is NULL\n");
return -ENODEV;
}
if (memcmp(&peasycap->telltale[0], TELLTALE, strlen(TELLTALE))) {
SAY("ERROR: bad peasycap\n");
return -EFAULT;
}
if (0 > peasycap->minor) {
SAY("ERROR: no minor\n");
return -ENODEV;