ALSA: usb: stream: refactor uac3 audio interface parsing
authorRuslan Bilovol <ruslan.bilovol@gmail.com>
Fri, 4 May 2018 01:24:00 +0000 (04:24 +0300)
committerTakashi Iwai <tiwai@suse.de>
Fri, 4 May 2018 07:39:12 +0000 (09:39 +0200)
Offload snd_usb_parse_audio_interface() function
which became quite long after adding UAC3 spec support.

Move class-specific parts of uac3 parsing to separate
function which now produce audioformat structure that
is ready to be fed to snd_usb_add_audio_stream().

Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/usb/stream.c

index 3369226..764be07 100644 (file)
@@ -807,19 +807,154 @@ found_clock:
        return fp;
 }
 
+static struct audioformat *
+snd_usb_get_audioformat_uac3(struct snd_usb_audio *chip,
+                            struct usb_host_interface *alts,
+                            int iface_no, int altset_idx,
+                            int altno, int stream)
+{
+       struct usb_device *dev = chip->dev;
+       struct uac3_input_terminal_descriptor *input_term;
+       struct uac3_output_terminal_descriptor *output_term;
+       struct uac3_cluster_header_descriptor *cluster;
+       struct uac3_as_header_descriptor *as;
+       struct uac3_hc_descriptor_header hc_header;
+       struct snd_pcm_chmap_elem *chmap;
+       unsigned int num_channels;
+       struct audioformat *fp;
+       u16 cluster_id, wLength;
+       int clock = 0;
+       int err;
+
+       as = snd_usb_find_csint_desc(alts->extra, alts->extralen,
+                                    NULL, UAC_AS_GENERAL);
+       if (!as) {
+               dev_err(&dev->dev,
+                       "%u:%d : UAC_AS_GENERAL descriptor not found\n",
+                       iface_no, altno);
+               return NULL;
+       }
+
+       if (as->bLength < sizeof(*as)) {
+               dev_err(&dev->dev,
+                       "%u:%d : invalid UAC_AS_GENERAL desc\n",
+                       iface_no, altno);
+               return NULL;
+       }
+
+       cluster_id = le16_to_cpu(as->wClusterDescrID);
+       if (!cluster_id) {
+               dev_err(&dev->dev,
+                       "%u:%d : no cluster descriptor\n",
+                       iface_no, altno);
+               return NULL;
+       }
+
+       /*
+        * Get number of channels and channel map through
+        * High Capability Cluster Descriptor
+        *
+        * First step: get High Capability header and
+        * read size of Cluster Descriptor
+        */
+       err = snd_usb_ctl_msg(chip->dev,
+                       usb_rcvctrlpipe(chip->dev, 0),
+                       UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
+                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+                       cluster_id,
+                       snd_usb_ctrl_intf(chip),
+                       &hc_header, sizeof(hc_header));
+       if (err < 0)
+               return ERR_PTR(err);
+       else if (err != sizeof(hc_header)) {
+               dev_err(&dev->dev,
+                       "%u:%d : can't get High Capability descriptor\n",
+                       iface_no, altno);
+               return ERR_PTR(-EIO);
+       }
+
+       /*
+        * Second step: allocate needed amount of memory
+        * and request Cluster Descriptor
+        */
+       wLength = le16_to_cpu(hc_header.wLength);
+       cluster = kzalloc(wLength, GFP_KERNEL);
+       if (!cluster)
+               return ERR_PTR(-ENOMEM);
+       err = snd_usb_ctl_msg(chip->dev,
+                       usb_rcvctrlpipe(chip->dev, 0),
+                       UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
+                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+                       cluster_id,
+                       snd_usb_ctrl_intf(chip),
+                       cluster, wLength);
+       if (err < 0) {
+               kfree(cluster);
+               return ERR_PTR(err);
+       } else if (err != wLength) {
+               dev_err(&dev->dev,
+                       "%u:%d : can't get Cluster Descriptor\n",
+                       iface_no, altno);
+               kfree(cluster);
+               return ERR_PTR(-EIO);
+       }
+
+       num_channels = cluster->bNrChannels;
+       chmap = convert_chmap_v3(cluster);
+       kfree(cluster);
+
+       /*
+        * lookup the terminal associated to this interface
+        * to extract the clock
+        */
+       input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
+                                                           as->bTerminalLink);
+       if (input_term) {
+               clock = input_term->bCSourceID;
+               goto found_clock;
+       }
+
+       output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
+                                                            as->bTerminalLink);
+       if (output_term) {
+               clock = output_term->bCSourceID;
+               goto found_clock;
+       }
+
+       dev_err(&dev->dev, "%u:%d : bogus bTerminalLink %d\n",
+                       iface_no, altno, as->bTerminalLink);
+       return NULL;
+
+found_clock:
+       fp = audio_format_alloc_init(chip, alts, UAC_VERSION_3, iface_no,
+                                    altset_idx, altno, num_channels, clock);
+       if (!fp)
+               return ERR_PTR(-ENOMEM);
+
+       fp->attributes = parse_uac_endpoint_attributes(chip, alts,
+                                                      UAC_VERSION_3,
+                                                      iface_no);
+       fp->chmap = chmap;
+
+       /* ok, let's parse further... */
+       if (snd_usb_parse_audio_format_v3(chip, fp, as, stream) < 0) {
+               kfree(fp->rate_table);
+               kfree(fp);
+               return NULL;
+       }
+
+       return fp;
+}
+
 int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
 {
        struct usb_device *dev;
        struct usb_interface *iface;
        struct usb_host_interface *alts;
        struct usb_interface_descriptor *altsd;
-       struct uac3_as_header_descriptor *as = NULL;
        int i, altno, err, stream;
-       u64 format = 0;
-       unsigned int num_channels = 0;
        struct audioformat *fp = NULL;
-       int num, protocol, clock = 0;
-       struct snd_pcm_chmap_elem *chmap_v3 = NULL;
+       int num, protocol;
 
        dev = chip->dev;
 
@@ -900,149 +1035,17 @@ int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
                                                           stream, bm_quirk);
                        break;
                }
-               case UAC_VERSION_3: {
-                       struct uac3_input_terminal_descriptor *input_term;
-                       struct uac3_output_terminal_descriptor *output_term;
-                       struct uac3_cluster_header_descriptor *cluster;
-                       struct uac3_hc_descriptor_header hc_header;
-                       u16 cluster_id, wLength;
-
-                       as = snd_usb_find_csint_desc(alts->extra,
-                                                       alts->extralen,
-                                                       NULL, UAC_AS_GENERAL);
-
-                       if (!as) {
-                               dev_err(&dev->dev,
-                                       "%u:%d : UAC_AS_GENERAL descriptor not found\n",
-                                       iface_no, altno);
-                               continue;
-                       }
-
-                       if (as->bLength < sizeof(*as)) {
-                               dev_err(&dev->dev,
-                                       "%u:%d : invalid UAC_AS_GENERAL desc\n",
-                                       iface_no, altno);
-                               continue;
-                       }
-
-                       cluster_id = le16_to_cpu(as->wClusterDescrID);
-                       if (!cluster_id) {
-                               dev_err(&dev->dev,
-                                       "%u:%d : no cluster descriptor\n",
-                                       iface_no, altno);
-                               continue;
-                       }
-
-                       /*
-                        * Get number of channels and channel map through
-                        * High Capability Cluster Descriptor
-                        *
-                        * First step: get High Capability header and
-                        * read size of Cluster Descriptor
-                        */
-                       err = snd_usb_ctl_msg(chip->dev,
-                                       usb_rcvctrlpipe(chip->dev, 0),
-                                       UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
-                                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                                       cluster_id,
-                                       snd_usb_ctrl_intf(chip),
-                                       &hc_header, sizeof(hc_header));
-                       if (err < 0)
-                               return err;
-                       else if (err != sizeof(hc_header)) {
-                               dev_err(&dev->dev,
-                                       "%u:%d : can't get High Capability descriptor\n",
-                                       iface_no, altno);
-                               return -EIO;
-                       }
-
-                       /*
-                        * Second step: allocate needed amount of memory
-                        * and request Cluster Descriptor
-                        */
-                       wLength = le16_to_cpu(hc_header.wLength);
-                       cluster = kzalloc(wLength, GFP_KERNEL);
-                       if (!cluster)
-                               return -ENOMEM;
-                       err = snd_usb_ctl_msg(chip->dev,
-                                       usb_rcvctrlpipe(chip->dev, 0),
-                                       UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
-                                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                                       cluster_id,
-                                       snd_usb_ctrl_intf(chip),
-                                       cluster, wLength);
-                       if (err < 0) {
-                               kfree(cluster);
-                               return err;
-                       } else if (err != wLength) {
-                               dev_err(&dev->dev,
-                                       "%u:%d : can't get Cluster Descriptor\n",
-                                       iface_no, altno);
-                               kfree(cluster);
-                               return -EIO;
-                       }
-
-                       num_channels = cluster->bNrChannels;
-                       chmap_v3 = convert_chmap_v3(cluster);
-
-                       kfree(cluster);
-
-                       format = le64_to_cpu(as->bmFormats);
-
-                       /* lookup the terminal associated to this interface
-                        * to extract the clock */
-                       input_term = snd_usb_find_input_terminal_descriptor(
-                                                       chip->ctrl_intf,
-                                                       as->bTerminalLink);
-
-                       if (input_term) {
-                               clock = input_term->bCSourceID;
-                               break;
-                       }
-
-                       output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
-                                                                             as->bTerminalLink);
-                       if (output_term) {
-                               clock = output_term->bCSourceID;
-                               break;
-                       }
-
-                       dev_err(&dev->dev,
-                               "%u:%d : bogus bTerminalLink %d\n",
-                               iface_no, altno, as->bTerminalLink);
-                       continue;
-               }
-               }
-
-               if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
-                       if (!fp)
-                               continue;
-                       else if (IS_ERR(fp))
-                               return PTR_ERR(fp);
-
-                       goto skip_uac3;
+               case UAC_VERSION_3:
+                       fp = snd_usb_get_audioformat_uac3(chip, alts,
+                                               iface_no, i, altno, stream);
+                       break;
                }
 
-               fp = audio_format_alloc_init(chip, alts, protocol, iface_no, i,
-                                            altno, num_channels, clock);
                if (!fp)
-                       return -ENOMEM;
-
-               fp->attributes = parse_uac_endpoint_attributes(chip, alts,
-                                                              protocol,
-                                                              iface_no);
-               fp->chmap = chmap_v3;
-
-               /* ok, let's parse further... */
-               if (snd_usb_parse_audio_format_v3(chip, fp, as,
-                                                       stream) < 0) {
-                       kfree(fp->rate_table);
-                       kfree(fp);
-                       fp = NULL;
                        continue;
-               }
+               else if (IS_ERR(fp))
+                       return PTR_ERR(fp);
 
-skip_uac3:
                dev_dbg(&dev->dev, "%u:%d: add audio endpoint %#x\n", iface_no, altno, fp->endpoint);
                err = snd_usb_add_audio_stream(chip, stream, fp);
                if (err < 0) {