ALSA: usb-audio: Use unsigned char for iface and altsettings fields

Just for consistency, use unsigned char for iface and altsetting in
allover places.  Also rearrange the field positions of
snd_usb_endpiont and tidy up with some comments.

Tested-by: Keith Milner <kamilner@superlative.org>
Tested-by: Dylan Robinson <dylan_robinson@motu.com>
Link: https://lore.kernel.org/r/20201123085347.19667-35-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/card.h b/sound/usb/card.h
index 3e16b92..6a027c3 100644 (file)
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -16,7 +16,7 @@ struct audioformat {
        unsigned int fmt_type;          /* USB audio format type (1-3) */
        unsigned int fmt_bits;          /* number of significant bits */
        unsigned int frame_size;        /* samples per frame for non-audio */
-       int iface;                      /* interface number */
+       unsigned char iface;            /* interface number */
        unsigned char altsetting;       /* corresponding alternate setting */
        unsigned char altset_idx;       /* array index of altenate setting */
        unsigned char attributes;       /* corresponding attributes of cs endpoint */
@@ -63,7 +63,12 @@ struct snd_usb_endpoint {
        atomic_t running;       /* running status */
        int ep_num;             /* the referenced endpoint number */
        int type;               /* SND_USB_ENDPOINT_TYPE_* */
-       unsigned long flags;
+
+       unsigned char iface;            /* interface number */
+       unsigned char altsetting;       /* corresponding alternate setting */
+       unsigned char ep_idx;           /* endpoint array index */
+
+       unsigned long flags;    /* running bit flags */
 
        void (*prepare_data_urb) (struct snd_usb_substream *subs,
                                  struct urb *urb);
@@ -112,8 +117,6 @@ struct snd_usb_endpoint {
        unsigned int syncinterval;      /* P for adaptive mode, 0 otherwise */
        unsigned char silence_value;
        unsigned int stride;
-       int iface, altsetting;
-       unsigned char ep_idx;           /* endpoint array index */
        int skip_packets;               /* quirks for devices to ignore the first n packets
                                           in a stream */
        bool implicit_fb_sync;          /* syncs with implicit feedback */

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 5f1d5f1..162da7a 100644 (file)
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -762,7 +762,7 @@ void snd_usb_endpoint_close(struct snd_usb_audio *chip,
                      ep->ep_num, ep->opened);
        if (!--ep->opened) {
                endpoint_set_interface(chip, ep, false);
-               ep->iface = -1;
+               ep->iface = 0;
                ep->altsetting = 0;
                ep->cur_audiofmt = NULL;
                ep->cur_rate = 0;