staging/easycap: reduce code nesting in easycap_sound.c

Reshuffle error handling to reduce indentation nesting
This reduce number of lines exceeding 80 characters
from 41 to 15

use:
if (error)
	(return, goto, continue)
CODE

instead of:

if (good)
	<CODE>
else
	<EXCEPTION HANDLING>

Cc: Dan Carpenter <error27@gmail.com>
Cc: Mike Thomas <rmthomas@sciolus.org>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 205 insertions, 213 deletions

diff --git a/drivers/staging/easycap/easycap_sound.c b/drivers/staging/easycap/easycap_sound.c
index 5829e26969d..a3402b00a8b 100644
--- a/drivers/staging/easycap/easycap_sound.c
+++ b/drivers/staging/easycap/easycap_sound.c
@@ -142,122 +142,118 @@ easycap_alsa_complete(struct urb *purb)
                             strerror(purb->iso_frame_desc[i].status),
                             purb->iso_frame_desc[i].status);
                 }
-                if (!purb->iso_frame_desc[i].status) {
-                        more = purb->iso_frame_desc[i].actual_length;
-                        if (!more)
-                                peasycap->audio_mt++;
-                        else {
-                                if (peasycap->audio_mt) {
-                                        JOM(12, "%4i empty audio urb frames\n",
-                                            peasycap->audio_mt);
-                                        peasycap->audio_mt = 0;
-                                }
+                if (purb->iso_frame_desc[i].status) {
+                        JOM(12, "discarding audio samples because "
+                            "%i=purb->iso_frame_desc[i].status\n",
+                            purb->iso_frame_desc[i].status);
+                        continue;
+                }
+                more = purb->iso_frame_desc[i].actual_length;
+                if (more == 0) {
+                        peasycap->audio_mt++;
+                        continue;
+                }
+                if (0 > more) {
+                        SAM("MISTAKE: more is negative\n");
+                        return;
+                }
 
-                                p1 = (u8 *)(purb->transfer_buffer +
-                                        purb->iso_frame_desc[i].offset);
-
-                                /*
-                                 *  COPY more BYTES FROM ISOC BUFFER
-                                 *  TO THE DMA BUFFER, CONVERTING
-                                 *  8-BIT MONO TO 16-BIT SIGNED
-                                 *  LITTLE-ENDIAN SAMPLES IF NECESSARY
-                                 */
-                                while (more) {
-                                        if (0 > more) {
-                                                SAM("MISTAKE: more is negative\n");
-                                                return;
-                                        }
-                                        much = dma_bytes - peasycap->dma_fill;
-                                        if (0 > much) {
-                                                SAM("MISTAKE: much is negative\n");
-                                                return;
-                                        }
-                                        if (0 == much) {
-                                                peasycap->dma_fill = 0;
-                                                peasycap->dma_next = fragment_bytes;
-                                                JOM(8, "wrapped dma buffer\n");
-                                        }
-                                        if (!peasycap->microphone) {
-                                                if (much > more)
-                                                        much = more;
-                                                memcpy(prt->dma_area +
-                                                       peasycap->dma_fill,
-                                                       p1, much);
-                                                p1 += much;
-                                                more -= much;
-                                        } else {
+                if (peasycap->audio_mt) {
+                        JOM(12, "%4i empty audio urb frames\n",
+                            peasycap->audio_mt);
+                        peasycap->audio_mt = 0;
+                }
+
+                p1 = (u8 *)(purb->transfer_buffer +
+                                purb->iso_frame_desc[i].offset);
+
+                /*
+                 *  COPY more BYTES FROM ISOC BUFFER
+                 *  TO THE DMA BUFFER, CONVERTING
+                 *  8-BIT MONO TO 16-BIT SIGNED
+                 *  LITTLE-ENDIAN SAMPLES IF NECESSARY
+                 */
+                while (more) {
+                        much = dma_bytes - peasycap->dma_fill;
+                        if (0 > much) {
+                                SAM("MISTAKE: much is negative\n");
+                                return;
+                        }
+                        if (0 == much) {
+                                peasycap->dma_fill = 0;
+                                peasycap->dma_next = fragment_bytes;
+                                JOM(8, "wrapped dma buffer\n");
+                        }
+                        if (!peasycap->microphone) {
+                                if (much > more)
+                                        much = more;
+                                memcpy(prt->dma_area + peasycap->dma_fill,
+                                        p1, much);
+                                p1 += much;
+                                more -= much;
+                        } else {
 #ifdef UPSAMPLE
-                                                if (much % 16)
-                                                        JOM(8, "MISTAKE? much"
-                                                            " is not divisible by 16\n");
-                                                if (much > (16 * more))
-                                                        much = 16 *
-                                                               more;
-                                                p2 = (u8 *)(prt->dma_area + peasycap->dma_fill);
-
-                                                for (j = 0;  j < (much/16);  j++) {
-                                                        newaudio =  ((int) *p1) - 128;
-                                                        newaudio = 128 * newaudio;
-
-                                                        delta = (newaudio - oldaudio) / 4;
-                                                        tmp = oldaudio + delta;
-
-                                                        for (k = 0;  k < 4;  k++) {
-                                                                *p2 = (0x00FF & tmp);
-                                                                *(p2 + 1) = (0xFF00 & tmp) >> 8;
-                                                                p2 += 2;
-                                                                *p2 = (0x00FF & tmp);
-                                                                *(p2 + 1) = (0xFF00 & tmp) >> 8;
-                                                                p2 += 2;
-                                                                tmp += delta;
-                                                        }
-                                                        p1++;
-                                                        more--;
-                                                        oldaudio = tmp;
-                                                }
+                                if (much % 16)
+                                        JOM(8, "MISTAKE? much"
+                                            " is not divisible by 16\n");
+                                if (much > (16 * more))
+                                        much = 16 * more;
+                                p2 = (u8 *)(prt->dma_area + peasycap->dma_fill);
+
+                                for (j = 0;  j < (much / 16);  j++) {
+                                        newaudio =  ((int) *p1) - 128;
+                                        newaudio = 128 * newaudio;
+
+                                        delta = (newaudio - oldaudio) / 4;
+                                        tmp = oldaudio + delta;
+
+                                        for (k = 0;  k < 4;  k++) {
+                                                *p2 = (0x00FF & tmp);
+                                                *(p2 + 1) = (0xFF00 & tmp) >> 8;
+                                                p2 += 2;
+                                                *p2 = (0x00FF & tmp);
+                                                *(p2 + 1) = (0xFF00 & tmp) >> 8;
+                                                p2 += 2;
+                                                tmp += delta;
+                                        }
+                                        p1++;
+                                        more--;
+                                        oldaudio = tmp;
+                                }
 #else /*!UPSAMPLE*/
-                                                if (much > (2 * more))
-                                                        much = 2 * more;
-                                                p2 = (u8 *)(prt->dma_area + peasycap->dma_fill);
-
-                                                for (j = 0;  j < (much / 2);  j++) {
-                                                        tmp = ((int) *p1) - 128;
-                                                        tmp = 128 * tmp;
-                                                        *p2 = (0x00FF & tmp);
-                                                        *(p2 + 1) = (0xFF00 & tmp) >> 8;
-                                                        p1++;
-                                                        p2 += 2;
-                                                        more--;
-                                                }
+                                if (much > (2 * more))
+                                        much = 2 * more;
+                                p2 = (u8 *)(prt->dma_area + peasycap->dma_fill);
+
+                                for (j = 0;  j < (much / 2);  j++) {
+                                        tmp = ((int) *p1) - 128;
+                                        tmp = 128 * tmp;
+                                        *p2 = (0x00FF & tmp);
+                                        *(p2 + 1) = (0xFF00 & tmp) >> 8;
+                                        p1++;
+                                        p2 += 2;
+                                        more--;
+                                }
 #endif /*UPSAMPLE*/
-                                        }
-                                        peasycap->dma_fill += much;
-                                        if (peasycap->dma_fill >= peasycap->dma_next) {
-                                                isfragment = peasycap->dma_fill / fragment_bytes;
-                                                if (0 > isfragment) {
-                                                        SAM("MISTAKE: isfragment is "
-                                                            "negative\n");
-                                                        return;
-                                                }
-                                                peasycap->dma_read = (isfragment - 1) * fragment_bytes;
-                                                peasycap->dma_next = (isfragment + 1) * fragment_bytes;
-                                                if (dma_bytes < peasycap->dma_next)
-                                                        peasycap->dma_next = fragment_bytes;
-
-                                                if (0 <= peasycap->dma_read) {
-                                                        JOM(8, "snd_pcm_period_elap"
-                                                            "sed(), %i="
-                                                            "isfragment\n",
-                                                            isfragment);
-                                                        snd_pcm_period_elapsed(pss);
-                                                }
-                                        }
+                        }
+                        peasycap->dma_fill += much;
+                        if (peasycap->dma_fill >= peasycap->dma_next) {
+                                isfragment = peasycap->dma_fill / fragment_bytes;
+                                if (0 > isfragment) {
+                                        SAM("MISTAKE: isfragment is negative\n");
+                                        return;
+                                }
+                                peasycap->dma_read = (isfragment - 1) * fragment_bytes;
+                                peasycap->dma_next = (isfragment + 1) * fragment_bytes;
+                                if (dma_bytes < peasycap->dma_next)
+                                        peasycap->dma_next = fragment_bytes;
+
+                                if (0 <= peasycap->dma_read) {
+                                        JOM(8, "snd_pcm_period_elapsed(), %i="
+                                            "isfragment\n", isfragment);
+                                        snd_pcm_period_elapsed(pss);
                                 }
                         }
-                } else {
-                        JOM(12, "discarding audio samples because "
-                            "%i=purb->iso_frame_desc[i].status\n",
-                            purb->iso_frame_desc[i].status);
                 }
 
 #ifdef UPSAMPLE
@@ -271,18 +267,18 @@ easycap_alsa_complete(struct urb *purb)
  */
 /*---------------------------------------------------------------------------*/
 resubmit:
-        if (peasycap->audio_isoc_streaming) {
-                rc = usb_submit_urb(purb, GFP_ATOMIC);
-                if (rc) {
-                        if ((-ENODEV != rc) && (-ENOENT != rc)) {
-                                SAM("ERROR: while %i=audio_idle, "
-                                    "usb_submit_urb() failed "
-                                    "with rc: -%s :%d\n", peasycap->audio_idle,
-                                    strerror(rc), rc);
-                        }
-                        if (0 < peasycap->audio_isoc_streaming)
-                                (peasycap->audio_isoc_streaming)--;
+        if (peasycap->audio_isoc_streaming == 0)
+                return;
+
+        rc = usb_submit_urb(purb, GFP_ATOMIC);
+        if (rc) {
+                if ((-ENODEV != rc) && (-ENOENT != rc)) {
+                        SAM("ERROR: while %i=audio_idle, usb_submit_urb failed "
+                            "with rc: -%s :%d\n",
+                                peasycap->audio_idle, strerror(rc), rc);
                 }
+                if (0 < peasycap->audio_isoc_streaming)
+                        peasycap->audio_isoc_streaming--;
         }
         return;
 }
@@ -643,10 +639,9 @@ int easycap_alsa_probe(struct easycap *peasycap)
                 SAM("ERROR: Cannot do ALSA snd_card_register()\n");
                 snd_card_free(psnd_card);
                 return -EFAULT;
-        } else {
-                ;
-                SAM("registered %s\n", &psnd_card->id[0]);
         }
+
+        SAM("registered %s\n", &psnd_card->id[0]);
         return 0;
 }
 #endif /*! CONFIG_EASYCAP_OSS */
@@ -737,83 +732,79 @@ submit_audio_urbs(struct easycap *peasycap)
                 SAM("ERROR: peasycap->pusb_device is NULL\n");
                 return -EFAULT;
         }
-        if (!peasycap->audio_isoc_streaming) {
-                JOM(4, "initial submission of all audio urbs\n");
-                rc = usb_set_interface(peasycap->pusb_device,
-                                       peasycap->audio_interface,
-                                       peasycap->audio_altsetting_on);
-                JOM(8, "usb_set_interface(.,%i,%i) returned %i\n",
-                    peasycap->audio_interface,
-                    peasycap->audio_altsetting_on, rc);
-
-                isbad = 0;
-                nospc = 0;
-                m = 0;
-                list_for_each(plist_head, (peasycap->purb_audio_head)) {
-                        pdata_urb = list_entry(plist_head, struct data_urb, list_head);
-                        if (pdata_urb) {
-                                purb = pdata_urb->purb;
-                                if (purb) {
-                                        isbuf = pdata_urb->isbuf;
-
-                                        purb->interval = 1;
-                                        purb->dev = peasycap->pusb_device;
-                                        purb->pipe = usb_rcvisocpipe(peasycap->pusb_device,
-                                                        peasycap->audio_endpointnumber);
-                                        purb->transfer_flags = URB_ISO_ASAP;
-                                        purb->transfer_buffer = peasycap->audio_isoc_buffer[isbuf].pgo;
-                                        purb->transfer_buffer_length = peasycap->audio_isoc_buffer_size;
+
+        if (peasycap->audio_isoc_streaming) {
+                JOM(4, "already streaming audio urbs\n");
+                return 0;
+        }
+
+        JOM(4, "initial submission of all audio urbs\n");
+        rc = usb_set_interface(peasycap->pusb_device,
+                               peasycap->audio_interface,
+                               peasycap->audio_altsetting_on);
+        JOM(8, "usb_set_interface(.,%i,%i) returned %i\n",
+            peasycap->audio_interface,
+            peasycap->audio_altsetting_on, rc);
+
+        isbad = 0;
+        nospc = 0;
+        m = 0;
+        list_for_each(plist_head, peasycap->purb_audio_head) {
+                pdata_urb = list_entry(plist_head, struct data_urb, list_head);
+                if (pdata_urb && pdata_urb->purb) {
+                        purb = pdata_urb->purb;
+                        isbuf = pdata_urb->isbuf;
+
+                        purb->interval = 1;
+                        purb->dev = peasycap->pusb_device;
+                        purb->pipe = usb_rcvisocpipe(peasycap->pusb_device,
+                                        peasycap->audio_endpointnumber);
+                        purb->transfer_flags = URB_ISO_ASAP;
+                        purb->transfer_buffer = peasycap->audio_isoc_buffer[isbuf].pgo;
+                        purb->transfer_buffer_length = peasycap->audio_isoc_buffer_size;
 #ifdef CONFIG_EASYCAP_OSS
-                                        purb->complete = easyoss_complete;
+                        purb->complete = easyoss_complete;
 #else /* CONFIG_EASYCAP_OSS */
-                                        purb->complete = easycap_alsa_complete;
+                        purb->complete = easycap_alsa_complete;
 #endif /* CONFIG_EASYCAP_OSS */
-                                        purb->context = peasycap;
-                                        purb->start_frame = 0;
-                                        purb->number_of_packets = peasycap->audio_isoc_framesperdesc;
-                                        for (j = 0;  j < peasycap->audio_isoc_framesperdesc; j++) {
-                                                purb->iso_frame_desc[j].offset = j * peasycap->audio_isoc_maxframesize;
-                                                purb->iso_frame_desc[j].length = peasycap->audio_isoc_maxframesize;
-                                        }
+                        purb->context = peasycap;
+                        purb->start_frame = 0;
+                        purb->number_of_packets = peasycap->audio_isoc_framesperdesc;
+                        for (j = 0;  j < peasycap->audio_isoc_framesperdesc; j++) {
+                                purb->iso_frame_desc[j].offset = j * peasycap->audio_isoc_maxframesize;
+                                purb->iso_frame_desc[j].length = peasycap->audio_isoc_maxframesize;
+                        }
 
-                                        rc = usb_submit_urb(purb, GFP_KERNEL);
-                                        if (rc) {
-                                                isbad++;
-                                                SAM("ERROR: usb_submit_urb() failed"
-                                                    " for urb with rc: -%s: %d\n",
-                                                    strerror(rc), rc);
-                                        } else {
-                                                m++;
-                                        }
-                                } else {
-                                        isbad++;
-                                }
-                        } else {
+                        rc = usb_submit_urb(purb, GFP_KERNEL);
+                        if (rc) {
                                 isbad++;
+                                SAM("ERROR: usb_submit_urb() failed"
+                                    " for urb with rc: -%s: %d\n",
+                                    strerror(rc), rc);
+                        } else {
+                                m++;
                         }
-                }
-                if (nospc) {
-                        SAM("-ENOSPC=usb_submit_urb() for %i urbs\n", nospc);
-                        SAM(".....  possibly inadequate USB bandwidth\n");
-                        peasycap->audio_eof = 1;
-                }
-                if (isbad) {
-                        JOM(4, "attempting cleanup instead of submitting\n");
-                        list_for_each(plist_head, (peasycap->purb_audio_head)) {
-                                pdata_urb = list_entry(plist_head, struct data_urb, list_head);
-                                if (pdata_urb) {
-                                        purb = pdata_urb->purb;
-                                        if (purb)
-                                                usb_kill_urb(purb);
-                                }
-                        }
-                        peasycap->audio_isoc_streaming = 0;
                 } else {
-                        peasycap->audio_isoc_streaming = m;
-                        JOM(4, "submitted %i audio urbs\n", m);
+                        isbad++;
                 }
-        } else
-                JOM(4, "already streaming audio urbs\n");
+        }
+        if (nospc) {
+                SAM("-ENOSPC=usb_submit_urb() for %i urbs\n", nospc);
+                SAM(".....  possibly inadequate USB bandwidth\n");
+                peasycap->audio_eof = 1;
+        }
+        if (isbad) {
+                JOM(4, "attempting cleanup instead of submitting\n");
+                list_for_each(plist_head, (peasycap->purb_audio_head)) {
+                        pdata_urb = list_entry(plist_head, struct data_urb, list_head);
+                        if (pdata_urb && pdata_urb->purb)
+                                usb_kill_urb(pdata_urb->purb);
+                }
+                peasycap->audio_isoc_streaming = 0;
+        } else {
+                peasycap->audio_isoc_streaming = m;
+                JOM(4, "submitted %i audio urbs\n", m);
+        }
 
         return 0;
 }
@@ -834,29 +825,30 @@ kill_audio_urbs(struct easycap *peasycap)
                 SAY("ERROR: peasycap is NULL\n");
                 return -EFAULT;
         }
-        if (peasycap->audio_isoc_streaming) {
-                if (peasycap->purb_audio_head) {
-                        peasycap->audio_isoc_streaming = 0;
-                        JOM(4, "killing audio urbs\n");
-                        m = 0;
-                        list_for_each(plist_head, (peasycap->purb_audio_head)) {
-                                pdata_urb = list_entry(plist_head, struct data_urb, list_head);
-                                if (pdata_urb) {
-                                        if (pdata_urb->purb) {
-                                                usb_kill_urb(pdata_urb->purb);
-                                                m++;
-                                        }
-                                }
-                        }
-                        JOM(4, "%i audio urbs killed\n", m);
-                } else {
-                        SAM("ERROR: peasycap->purb_audio_head is NULL\n");
-                        return -EFAULT;
-                }
-        } else {
+
+        if (!peasycap->audio_isoc_streaming) {
                 JOM(8, "%i=audio_isoc_streaming, no audio urbs killed\n",
                     peasycap->audio_isoc_streaming);
+                return 0;
+        }
+
+        if (!peasycap->purb_audio_head) {
+                SAM("ERROR: peasycap->purb_audio_head is NULL\n");
+                return -EFAULT;
         }
+
+        peasycap->audio_isoc_streaming = 0;
+        JOM(4, "killing audio urbs\n");
+        m = 0;
+        list_for_each(plist_head, (peasycap->purb_audio_head)) {
+                pdata_urb = list_entry(plist_head, struct data_urb, list_head);
+                if (pdata_urb && pdata_urb->purb) {
+                        usb_kill_urb(pdata_urb->purb);
+                        m++;
+                }
+        }
+        JOM(4, "%i audio urbs killed\n", m);
+
         return 0;
 }
 /*****************************************************************************/