[media] staging: easycap: Split device struct alloc and retrieval code

When the device is probed a driver struct is either
allocated or retrieved.
This operation is logically splitted in several functions.

Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 216 insertions, 168 deletions

diff --git a/drivers/staging/media/easycap/easycap_main.c b/drivers/staging/media/easycap/easycap_main.c
index d0fe34afc2e5..c4198be6344c 100644
--- a/drivers/staging/media/easycap/easycap_main.c
+++ b/drivers/staging/media/easycap/easycap_main.c
@@ -2842,6 +2842,209 @@ static void easycap_complete(struct urb *purb)
         return;
 }
 
+static struct easycap *alloc_easycap(u8 bInterfaceNumber)
+{
+        struct easycap *peasycap;
+        int i;
+
+        peasycap = kzalloc(sizeof(struct easycap), GFP_KERNEL);
+        if (!peasycap) {
+                SAY("ERROR: Could not allocate peasycap\n");
+                return NULL;
+        }
+
+        if (mutex_lock_interruptible(&mutex_dongle)) {
+                SAY("ERROR: cannot lock mutex_dongle\n");
+                kfree(peasycap);
+                return NULL;
+        }
+
+        /* Find a free dongle in easycapdc60_dongle array */
+        for (i = 0; i < DONGLE_MANY; i++) {
+
+                if ((!easycapdc60_dongle[i].peasycap) &&
+                    (!mutex_is_locked(&easycapdc60_dongle[i].mutex_video)) &&
+                    (!mutex_is_locked(&easycapdc60_dongle[i].mutex_audio))) {
+
+                        easycapdc60_dongle[i].peasycap = peasycap;
+                        peasycap->isdongle = i;
+                        JOM(8, "intf[%i]: peasycap-->easycap"
+                                "_dongle[%i].peasycap\n",
+                                bInterfaceNumber, i);
+                        break;
+                }
+        }
+
+        mutex_unlock(&mutex_dongle);
+
+        if (i >= DONGLE_MANY) {
+                SAM("ERROR: too many dongles\n");
+                kfree(peasycap);
+                return NULL;
+        }
+
+        return peasycap;
+}
+
+/*
+ * FIXME: Identify the appropriate pointer peasycap for interfaces
+ * 1 and 2. The address of peasycap->pusb_device is reluctantly used
+ * for this purpose.
+ */
+static struct easycap *get_easycap(struct usb_device *usbdev,
+                                   u8 bInterfaceNumber)
+{
+        int i;
+        struct easycap *peasycap;
+
+        for (i = 0; i < DONGLE_MANY; i++) {
+                if (easycapdc60_dongle[i].peasycap->pusb_device == usbdev) {
+                        peasycap = easycapdc60_dongle[i].peasycap;
+                        JOT(8, "intf[%i]: dongle[%i].peasycap\n",
+                                        bInterfaceNumber, i);
+                        break;
+                }
+        }
+        if (i >= DONGLE_MANY) {
+                SAY("ERROR: peasycap is unknown when probing interface %i\n",
+                        bInterfaceNumber);
+                return NULL;
+        }
+        if (!peasycap) {
+                SAY("ERROR: peasycap is NULL when probing interface %i\n",
+                        bInterfaceNumber);
+                return NULL;
+        }
+
+        return peasycap;
+}
+
+static void init_easycap(struct easycap *peasycap,
+                         struct usb_device *usbdev,
+                         struct usb_interface *intf,
+                         u8 bInterfaceNumber)
+{
+        /* Save usb_device and usb_interface */
+        peasycap->pusb_device = usbdev;
+        peasycap->pusb_interface = intf;
+
+        peasycap->minor = -1;
+        kref_init(&peasycap->kref);
+        JOM(8, "intf[%i]: after kref_init(..._video) "
+                "%i=peasycap->kref.refcount.counter\n",
+                bInterfaceNumber, peasycap->kref.refcount.counter);
+
+        /* module params */
+        peasycap->gain = (s8)clamp(easycap_gain, 0, 31);
+
+        init_waitqueue_head(&peasycap->wq_video);
+        init_waitqueue_head(&peasycap->wq_audio);
+        init_waitqueue_head(&peasycap->wq_trigger);
+
+        peasycap->allocation_video_struct = sizeof(struct easycap);
+
+        peasycap->microphone = false;
+
+        peasycap->video_interface = -1;
+        peasycap->video_altsetting_on = -1;
+        peasycap->video_altsetting_off = -1;
+        peasycap->video_endpointnumber = -1;
+        peasycap->video_isoc_maxframesize = -1;
+        peasycap->video_isoc_buffer_size = -1;
+
+        peasycap->audio_interface = -1;
+        peasycap->audio_altsetting_on = -1;
+        peasycap->audio_altsetting_off = -1;
+        peasycap->audio_endpointnumber = -1;
+        peasycap->audio_isoc_maxframesize = -1;
+        peasycap->audio_isoc_buffer_size = -1;
+
+        peasycap->frame_buffer_many = FRAME_BUFFER_MANY;
+}
+
+static int populate_inputset(struct easycap *peasycap)
+{
+        struct inputset *inputset;
+        struct easycap_format *peasycap_format;
+        struct v4l2_pix_format *pix;
+        int m, i, k, mask, fmtidx;
+        s32 value;
+
+        inputset = peasycap->inputset;
+
+        /* FIXME: peasycap->ntsc is not yet initialized */
+        fmtidx = peasycap->ntsc ? NTSC_M : PAL_BGHIN;
+
+        m = 0;
+        mask = 0;
+        for (i = 0; easycap_standard[i].mask != 0xffff; i++) {
+                if (fmtidx == easycap_standard[i].v4l2_standard.index) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].standard_offset = i;
+                        mask = easycap_standard[i].mask;
+                }
+        }
+
+        if (m != 1) {
+                SAM("ERROR: inputset->standard_offset unpopulated, %i=m\n", m);
+                return -ENOENT;
+        }
+
+        peasycap_format = &easycap_format[0];
+        m = 0;
+        for (i = 0; peasycap_format->v4l2_format.fmt.pix.width; i++) {
+                pix = &peasycap_format->v4l2_format.fmt.pix;
+                if (((peasycap_format->mask & 0x0F) == (mask & 0x0F))
+                        && pix->field == V4L2_FIELD_NONE
+                        && pix->pixelformat == V4L2_PIX_FMT_UYVY
+                        && pix->width  == 640 && pix->height == 480) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].format_offset = i;
+                        break;
+                }
+                peasycap_format++;
+        }
+        if (m != 1) {
+                SAM("ERROR: inputset[]->format_offset unpopulated\n");
+                return -ENOENT;
+        }
+
+        m = 0;
+        for (i = 0; easycap_control[i].id != 0xffffffff; i++) {
+                value = easycap_control[i].default_value;
+                if (V4L2_CID_BRIGHTNESS == easycap_control[i].id) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].brightness = value;
+                } else if (V4L2_CID_CONTRAST == easycap_control[i].id) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].contrast = value;
+                } else if (V4L2_CID_SATURATION == easycap_control[i].id) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].saturation = value;
+                } else if (V4L2_CID_HUE == easycap_control[i].id) {
+                        m++;
+                        for (k = 0; k < INPUT_MANY; k++)
+                                inputset[k].hue = value;
+                }
+        }
+
+        if (m != 4) {
+                SAM("ERROR: inputset[]->brightness underpopulated\n");
+                return -ENOENT;
+        }
+
+        for (k = 0; k < INPUT_MANY; k++)
+                inputset[k].input = k;
+        JOM(4, "populated inputset[]\n");
+
+        return 0;
+}
+
 static const struct v4l2_file_operations v4l2_fops = {
         .owner          = THIS_MODULE,
         .open           = easycap_open_noinode,
@@ -2863,7 +3066,6 @@ static int easycap_usb_probe(struct usb_interface *intf,
         struct usb_interface_descriptor *interface;
         struct urb *purb;
         struct easycap *peasycap;
-        int ndong;
         struct data_urb *pdata_urb;
         int i, j, k, m, rc;
         u8 bInterfaceNumber;
@@ -2874,11 +3076,6 @@ static int easycap_usb_probe(struct usb_interface *intf,
         int okepn[8];
         int okmps[8];
         int maxpacketsize;
-        u16 mask;
-        s32 value;
-        struct easycap_format *peasycap_format;
-        int fmtidx;
-        struct inputset *inputset;
 
         usbdev = interface_to_usbdev(intf);
 
@@ -2916,76 +3113,16 @@ static int easycap_usb_probe(struct usb_interface *intf,
          * interfaces 1 and 2 are probed.
          */
         if (0 == bInterfaceNumber) {
-                peasycap = kzalloc(sizeof(struct easycap), GFP_KERNEL);
-                if (!peasycap) {
-                        SAY("ERROR: Could not allocate peasycap\n");
-                        return -ENOMEM;
-                }
-
-                /* Perform urgent initializations */
-                peasycap->minor = -1;
-                kref_init(&peasycap->kref);
-                JOM(8, "intf[%i]: after kref_init(..._video) "
-                                "%i=peasycap->kref.refcount.counter\n",
-                                bInterfaceNumber, peasycap->kref.refcount.counter);
-
-                /* module params */
-                peasycap->gain = (s8)clamp(easycap_gain, 0, 31);
-
-                init_waitqueue_head(&peasycap->wq_video);
-                init_waitqueue_head(&peasycap->wq_audio);
-                init_waitqueue_head(&peasycap->wq_trigger);
-
-                if (mutex_lock_interruptible(&mutex_dongle)) {
-                        SAY("ERROR: cannot down mutex_dongle\n");
-                        return -ERESTARTSYS;
-                }
-
-                for (ndong = 0; ndong < DONGLE_MANY; ndong++) {
-                        if ((!easycapdc60_dongle[ndong].peasycap) &&
-                                        (!mutex_is_locked(&easycapdc60_dongle
-                                                [ndong].mutex_video)) &&
-                                        (!mutex_is_locked(&easycapdc60_dongle
-                                                [ndong].mutex_audio))) {
-                                easycapdc60_dongle[ndong].peasycap = peasycap;
-                                peasycap->isdongle = ndong;
-                                JOM(8, "intf[%i]: peasycap-->easycap"
-                                                "_dongle[%i].peasycap\n",
-                                                bInterfaceNumber, ndong);
-                                break;
-                        }
-                }
-
-                if (DONGLE_MANY <= ndong) {
-                        SAM("ERROR: too many dongles\n");
-                        mutex_unlock(&mutex_dongle);
+                /*
+                 * Alloc structure and save it in a free slot in
+                 * easycapdc60_dongle array
+                 */
+                peasycap = alloc_easycap(bInterfaceNumber);
+                if (!peasycap)
                         return -ENOMEM;
-                }
-                mutex_unlock(&mutex_dongle);
 
-                peasycap->allocation_video_struct = sizeof(struct easycap);
-
-                /* and further initialize the structure */
-                peasycap->pusb_device = usbdev;
-                peasycap->pusb_interface = intf;
-
-                peasycap->microphone = false;
-
-                peasycap->video_interface = -1;
-                peasycap->video_altsetting_on = -1;
-                peasycap->video_altsetting_off = -1;
-                peasycap->video_endpointnumber = -1;
-                peasycap->video_isoc_maxframesize = -1;
-                peasycap->video_isoc_buffer_size = -1;
-
-                peasycap->audio_interface = -1;
-                peasycap->audio_altsetting_on = -1;
-                peasycap->audio_altsetting_off = -1;
-                peasycap->audio_endpointnumber = -1;
-                peasycap->audio_isoc_maxframesize = -1;
-                peasycap->audio_isoc_buffer_size = -1;
-
-                peasycap->frame_buffer_many = FRAME_BUFFER_MANY;
+                /* Perform basic struct initialization */
+                init_easycap(peasycap, usbdev, intf, bInterfaceNumber);
 
                 /* Dynamically fill in the available formats */
                 rc = easycap_video_fillin_formats();
@@ -2996,103 +3133,14 @@ static int easycap_usb_probe(struct usb_interface *intf,
                 JOM(4, "%i formats available\n", rc);
 
                 /* Populate easycap.inputset[] */
-                inputset = peasycap->inputset;
-                fmtidx = peasycap->ntsc ? NTSC_M : PAL_BGHIN;
-                m = 0;
-                mask = 0;
-                for (i = 0; 0xFFFF != easycap_standard[i].mask; i++) {
-                        if (fmtidx == easycap_standard[i].v4l2_standard.index) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].standard_offset = i;
-
-                                mask = easycap_standard[i].mask;
-                        }
-                }
-                if (1 != m) {
-                        SAM("ERROR: "
-                            "inputset->standard_offset unpopulated, %i=m\n", m);
-                        return -ENOENT;
-                }
-
-                peasycap_format = &easycap_format[0];
-                m = 0;
-                for (i = 0; peasycap_format->v4l2_format.fmt.pix.width; i++) {
-                        struct v4l2_pix_format *pix =
-                                &peasycap_format->v4l2_format.fmt.pix;
-                        if (((peasycap_format->mask & 0x0F) == (mask & 0x0F)) &&
-                            pix->field == V4L2_FIELD_NONE &&
-                            pix->pixelformat == V4L2_PIX_FMT_UYVY &&
-                            pix->width  == 640 && pix->height == 480) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].format_offset = i;
-                                break;
-                        }
-                        peasycap_format++;
-                }
-                if (1 != m) {
-                        SAM("ERROR: inputset[]->format_offset unpopulated\n");
-                        return -ENOENT;
-                }
-
-                m = 0;
-                for (i = 0; 0xFFFFFFFF != easycap_control[i].id; i++) {
-                        value = easycap_control[i].default_value;
-                        if (V4L2_CID_BRIGHTNESS == easycap_control[i].id) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].brightness = value;
-                        } else if (V4L2_CID_CONTRAST == easycap_control[i].id) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].contrast = value;
-                        } else if (V4L2_CID_SATURATION == easycap_control[i].id) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].saturation = value;
-                        } else if (V4L2_CID_HUE == easycap_control[i].id) {
-                                m++;
-                                for (k = 0; k < INPUT_MANY; k++)
-                                        inputset[k].hue = value;
-                        }
-                }
-
-                if (4 != m) {
-                        SAM("ERROR: inputset[]->brightness underpopulated\n");
-                        return -ENOENT;
-                }
-                for (k = 0; k < INPUT_MANY; k++)
-                        inputset[k].input = k;
-                JOM(4, "populated inputset[]\n");
+                rc = populate_inputset(peasycap);
+                if (rc < 0)
+                        return rc;
                 JOM(4, "finished initialization\n");
         } else {
-
-                /*
-                 * FIXME: Identify the appropriate pointer
-                 * peasycap for interfaces 1 and 2.
-                 * The address of peasycap->pusb_device
-                 * is reluctantly used for this purpose.
-                 */
-                for (ndong = 0; ndong < DONGLE_MANY; ndong++) {
-                        if (usbdev == easycapdc60_dongle[ndong].peasycap->
-                                                                        pusb_device) {
-                                peasycap = easycapdc60_dongle[ndong].peasycap;
-                                JOT(8, "intf[%i]: dongle[%i].peasycap\n",
-                                                bInterfaceNumber, ndong);
-                                break;
-                        }
-                }
-                if (DONGLE_MANY <= ndong) {
-                        SAY("ERROR: peasycap is unknown when probing interface %i\n",
-                                                                bInterfaceNumber);
+                peasycap = get_easycap(usbdev, bInterfaceNumber);
+                if (!peasycap)
                         return -ENODEV;
-                }
-                if (!peasycap) {
-                        SAY("ERROR: peasycap is NULL when probing interface %i\n",
-                                                                bInterfaceNumber);
-                        return -ENODEV;
-                }
         }
 
         if ((USB_CLASS_VIDEO == bInterfaceClass) ||