ALSA: usb-audio: Tidy up mixer_us16x08.c

A few more cleanups and improvements that have been overlooked:

- Use ARRAY_SIZE() macro appropriately
- Code shuffling for minor optimization
- Omit superfluous variable initializations
- Get rid of superfluous NULL checks
- Add const to snd_us16x08_control_params definitions

No functional changes.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 50 insertions, 82 deletions

diff --git a/sound/usb/mixer_us16x08.c b/sound/usb/mixer_us16x08.c
index f7289541fbce..dc48eedea92e 100644
--- a/sound/usb/mixer_us16x08.c
+++ b/sound/usb/mixer_us16x08.c
@@ -176,15 +176,9 @@ static int snd_us16x08_recv_urb(struct snd_usb_audio *chip,
  */
 static int snd_us16x08_send_urb(struct snd_usb_audio *chip, char *buf, int size)
 {
-        int err = 0;
-
-        if (chip) {
-                err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
+        return snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
                         SND_US16X08_URB_REQUEST, SND_US16X08_URB_REQUESTTYPE,
                         0, 0, buf, size);
-        }
-
-        return err;
 }
 
 static int snd_us16x08_route_info(struct snd_kcontrol *kcontrol,
@@ -212,10 +206,7 @@ static int snd_us16x08_route_put(struct snd_kcontrol *kcontrol,
         struct snd_usb_audio *chip = elem->head.mixer->chip;
         int index = ucontrol->id.index;
         char buf[sizeof(route_msg)];
-        int val, val_org, err = 0;
-
-        /* prepare the message buffer from template */
-        memcpy(buf, route_msg, sizeof(route_msg));
+        int val, val_org, err;
 
         /*  get the new value (no bias for routes) */
         val = ucontrol->value.enumerated.item[0];
@@ -224,6 +215,9 @@ static int snd_us16x08_route_put(struct snd_kcontrol *kcontrol,
         if (val < 0 || val > 9)
                 return -EINVAL;
 
+        /* prepare the message buffer from template */
+        memcpy(buf, route_msg, sizeof(route_msg));
+
         if (val < 2) {
                 /* input comes from a master channel */
                 val_org = val;
@@ -279,12 +273,9 @@ static int snd_us16x08_master_put(struct snd_kcontrol *kcontrol,
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
         struct snd_usb_audio *chip = elem->head.mixer->chip;
         char buf[sizeof(mix_msg_out)];
-        int val, err = 0;
+        int val, err;
         int index = ucontrol->id.index;
 
-        /* prepare the message buffer from template */
-        memcpy(buf, mix_msg_out, sizeof(mix_msg_out));
-
         /* new control value incl. bias*/
         val = ucontrol->value.integer.value[0];
 
@@ -293,6 +284,9 @@ static int snd_us16x08_master_put(struct snd_kcontrol *kcontrol,
                 || val > SND_US16X08_KCMAX(kcontrol))
                 return -EINVAL;
 
+        /* prepare the message buffer from template */
+        memcpy(buf, mix_msg_out, sizeof(mix_msg_out));
+
         buf[8] = val - SND_US16X08_KCBIAS(kcontrol);
         buf[6] = elem->head.id;
 
@@ -392,9 +386,6 @@ static int snd_us16x08_channel_put(struct snd_kcontrol *kcontrol,
         int val, err;
         int index = ucontrol->id.index;
 
-        /* prepare URB message from template */
-        memcpy(buf, mix_msg_in, sizeof(mix_msg_in));
-
         val = ucontrol->value.integer.value[0];
 
         /* sanity check */
@@ -402,6 +393,9 @@ static int snd_us16x08_channel_put(struct snd_kcontrol *kcontrol,
                 || val > SND_US16X08_KCMAX(kcontrol))
                 return -EINVAL;
 
+        /* prepare URB message from template */
+        memcpy(buf, mix_msg_in, sizeof(mix_msg_in));
+
         /* add the bias to the new value */
         buf[8] = val - SND_US16X08_KCBIAS(kcontrol);
         buf[6] = elem->head.id;
@@ -434,8 +428,7 @@ static int snd_us16x08_comp_get(struct snd_kcontrol *kcontrol,
         struct snd_ctl_elem_value *ucontrol)
 {
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
-        struct snd_us16x08_comp_store *store =
-                ((struct snd_us16x08_comp_store *) elem->private_data);
+        struct snd_us16x08_comp_store *store = elem->private_data;
         int index = ucontrol->id.index;
         int val_idx = COMP_STORE_IDX(elem->head.id);
 
@@ -449,18 +442,11 @@ static int snd_us16x08_comp_put(struct snd_kcontrol *kcontrol,
 {
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
         struct snd_usb_audio *chip = elem->head.mixer->chip;
-        struct snd_us16x08_comp_store *store =
-                ((struct snd_us16x08_comp_store *) elem->private_data);
+        struct snd_us16x08_comp_store *store = elem->private_data;
         int index = ucontrol->id.index;
         char buf[sizeof(comp_msg)];
         int val_idx, val;
-        int err = 0;
-
-        /* prepare compressor URB message from template  */
-        memcpy(buf, comp_msg, sizeof(comp_msg));
-
-        /* new control value incl. bias*/
-        val_idx = elem->head.id - SND_US16X08_ID_COMP_BASE;
+        int err;
 
         val = ucontrol->value.integer.value[0];
 
@@ -469,8 +455,14 @@ static int snd_us16x08_comp_put(struct snd_kcontrol *kcontrol,
                 || val > SND_US16X08_KCMAX(kcontrol))
                 return -EINVAL;
 
+        /* new control value incl. bias*/
+        val_idx = elem->head.id - SND_US16X08_ID_COMP_BASE;
+
         store->val[val_idx][index] = ucontrol->value.integer.value[0];
 
+        /* prepare compressor URB message from template  */
+        memcpy(buf, comp_msg, sizeof(comp_msg));
+
         /* place comp values in message buffer watch bias! */
         buf[8] = store->val[
                 COMP_STORE_IDX(SND_US16X08_ID_COMP_THRESHOLD)][index]
@@ -502,10 +494,9 @@ static int snd_us16x08_comp_put(struct snd_kcontrol *kcontrol,
 static int snd_us16x08_eqswitch_get(struct snd_kcontrol *kcontrol,
         struct snd_ctl_elem_value *ucontrol)
 {
-        int val = 0;
+        int val;
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
-        struct snd_us16x08_eq_store *store =
-                ((struct snd_us16x08_eq_store *) elem->private_data);
+        struct snd_us16x08_eq_store *store = elem->private_data;
         int index = ucontrol->id.index;
 
         /* get low switch from cache is enough, cause all bands are together */
@@ -521,10 +512,8 @@ static int snd_us16x08_eqswitch_put(struct snd_kcontrol *kcontrol,
 {
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
         struct snd_usb_audio *chip = elem->head.mixer->chip;
-        struct snd_us16x08_eq_store *store =
-                ((struct snd_us16x08_eq_store *) elem->private_data);
+        struct snd_us16x08_eq_store *store = elem->private_data;
         int index = ucontrol->id.index;
-
         char buf[sizeof(eqs_msq)];
         int val, err = 0;
         int b_idx;
@@ -564,10 +553,9 @@ static int snd_us16x08_eqswitch_put(struct snd_kcontrol *kcontrol,
 static int snd_us16x08_eq_get(struct snd_kcontrol *kcontrol,
         struct snd_ctl_elem_value *ucontrol)
 {
-        int val = 0;
+        int val;
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
-        struct snd_us16x08_eq_store *store =
-                ((struct snd_us16x08_eq_store *) elem->private_data);
+        struct snd_us16x08_eq_store *store = elem->private_data;
         int index = ucontrol->id.index;
         int b_idx = EQ_STORE_BAND_IDX(elem->head.id) - 1;
         int p_idx = EQ_STORE_PARAM_IDX(elem->head.id);
@@ -584,17 +572,13 @@ static int snd_us16x08_eq_put(struct snd_kcontrol *kcontrol,
 {
         struct usb_mixer_elem_info *elem = kcontrol->private_data;
         struct snd_usb_audio *chip = elem->head.mixer->chip;
-        struct snd_us16x08_eq_store *store =
-                ((struct snd_us16x08_eq_store *) elem->private_data);
+        struct snd_us16x08_eq_store *store = elem->private_data;
         int index = ucontrol->id.index;
         char buf[sizeof(eqs_msq)];
-        int val, err = 0;
+        int val, err;
         int b_idx = EQ_STORE_BAND_IDX(elem->head.id) - 1;
         int p_idx = EQ_STORE_PARAM_IDX(elem->head.id);
 
-        /* copy URB buffer from EQ template */
-        memcpy(buf, eqs_msq, sizeof(eqs_msq));
-
         val = ucontrol->value.integer.value[0];
 
         /* sanity check */
@@ -602,6 +586,9 @@ static int snd_us16x08_eq_put(struct snd_kcontrol *kcontrol,
                 || val > SND_US16X08_KCMAX(kcontrol))
                 return -EINVAL;
 
+        /* copy URB buffer from EQ template */
+        memcpy(buf, eqs_msq, sizeof(eqs_msq));
+
         store->val[b_idx][p_idx][index] = val;
         buf[20] = store->val[b_idx][3][index];
         buf[17] = store->val[b_idx][2][index];
@@ -713,12 +700,6 @@ static int snd_us16x08_meter_get(struct snd_kcontrol *kcontrol,
         u8 meter_urb[64];
         char tmp[sizeof(mix_init_msg2)] = {0};
 
-        if (elem) {
-                store = (struct snd_us16x08_meter_store *) elem->private_data;
-                chip = elem->head.mixer->chip;
-        } else
-                return 0;
-
         switch (kcontrol->private_value) {
         case 0:
                 snd_us16x08_send_urb(chip, (char *)mix_init_msg1,
@@ -983,11 +964,11 @@ static struct snd_kcontrol_new snd_us16x08_meter_ctl = {
 /* setup compressor store and assign default value */
 static struct snd_us16x08_comp_store *snd_us16x08_create_comp_store(void)
 {
-        int i = 0;
-        struct snd_us16x08_comp_store *tmp =
-                kmalloc(sizeof(struct snd_us16x08_comp_store), GFP_KERNEL);
+        int i;
+        struct snd_us16x08_comp_store *tmp;
 
-        if (tmp == NULL)
+        tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+        if (!tmp)
                 return NULL;
 
         for (i = 0; i < SND_US16X08_MAX_CHANNELS; i++) {
@@ -1006,10 +987,10 @@ static struct snd_us16x08_comp_store *snd_us16x08_create_comp_store(void)
 static struct snd_us16x08_eq_store *snd_us16x08_create_eq_store(void)
 {
         int i, b_idx;
-        struct snd_us16x08_eq_store *tmp =
-                kmalloc(sizeof(struct snd_us16x08_eq_store), GFP_KERNEL);
+        struct snd_us16x08_eq_store *tmp;
 
-        if (tmp == NULL)
+        tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+        if (!tmp)
                 return NULL;
 
         for (i = 0; i < SND_US16X08_MAX_CHANNELS; i++) {
@@ -1042,15 +1023,14 @@ static struct snd_us16x08_eq_store *snd_us16x08_create_eq_store(void)
 
 static struct snd_us16x08_meter_store *snd_us16x08_create_meter_store(void)
 {
-        struct snd_us16x08_meter_store *tmp =
-                kzalloc(sizeof(struct snd_us16x08_meter_store), GFP_KERNEL);
+        struct snd_us16x08_meter_store *tmp;
 
+        tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
         if (!tmp)
                 return NULL;
         tmp->comp_index = 1;
         tmp->comp_active_index = 0;
         return tmp;
-
 }
 
 /* release elem->private_free as well; called only once for each *_store */
@@ -1067,7 +1047,7 @@ static void elem_private_free(struct snd_kcontrol *kctl)
 static int add_new_ctl(struct usb_mixer_interface *mixer,
         const struct snd_kcontrol_new *ncontrol,
         int index, int val_type, int channels,
-        const char *name, const void *opt,
+        const char *name, void *opt,
         bool do_private_free,
         struct usb_mixer_elem_info **elem_ret)
 {
@@ -1088,7 +1068,7 @@ static int add_new_ctl(struct usb_mixer_interface *mixer,
         elem->head.id = index;
         elem->val_type = val_type;
         elem->channels = channels;
-        elem->private_data = (void *) opt;
+        elem->private_data = opt;
 
         kctl = snd_ctl_new1(ncontrol, elem);
         if (!kctl) {
@@ -1113,10 +1093,8 @@ static int add_new_ctl(struct usb_mixer_interface *mixer,
         return 0;
 }
 
-static struct snd_us16x08_control_params control_params;
-
 /* table of EQ controls */
-static struct snd_us16x08_control_params eq_controls[] = {
+static const struct snd_us16x08_control_params eq_controls[] = {
         { /* EQ switch */
                 .kcontrol_new = &snd_us16x08_eq_switch_ctl,
                 .control_id = SND_US16X08_ID_EQENABLE,
@@ -1197,7 +1175,7 @@ static struct snd_us16x08_control_params eq_controls[] = {
 };
 
 /* table of compressor controls */
-static struct snd_us16x08_control_params comp_controls[] = {
+static const struct snd_us16x08_control_params comp_controls[] = {
         { /* Comp enable */
                 .kcontrol_new = &snd_us16x08_compswitch_ctl,
                 .control_id = SND_US16X08_ID_COMP_SWITCH,
@@ -1243,7 +1221,7 @@ static struct snd_us16x08_control_params comp_controls[] = {
 };
 
 /* table of channel controls */
-static struct snd_us16x08_control_params channel_controls[] = {
+static const struct snd_us16x08_control_params channel_controls[] = {
         { /* Phase */
                 .kcontrol_new = &snd_us16x08_ch_boolean_ctl,
                 .control_id = SND_US16X08_ID_PHASE,
@@ -1279,7 +1257,7 @@ static struct snd_us16x08_control_params channel_controls[] = {
 };
 
 /* table of master controls */
-static struct snd_us16x08_control_params master_controls[] = {
+static const struct snd_us16x08_control_params master_controls[] = {
         { /* Master */
                 .kcontrol_new = &snd_us16x08_master_ctl,
                 .control_id = SND_US16X08_ID_FADER,
@@ -1347,10 +1325,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
                         return -ENOMEM;
 
                 /* add master controls */
-                for (i = 0;
-                        i < sizeof(master_controls)
-                        / sizeof(control_params);
-                        i++) {
+                for (i = 0; i < ARRAY_SIZE(master_controls); i++) {
 
                         err = add_new_ctl(mixer,
                                 master_controls[i].kcontrol_new,
@@ -1368,10 +1343,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
                 }
 
                 /* add channel controls */
-                for (i = 0;
-                        i < sizeof(channel_controls)
-                        / sizeof(control_params);
-                        i++) {
+                for (i = 0; i < ARRAY_SIZE(channel_controls); i++) {
 
                         err = add_new_ctl(mixer,
                                 channel_controls[i].kcontrol_new,
@@ -1396,8 +1368,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
                         return -ENOMEM;
 
                 /* add EQ controls */
-                for (i = 0; i < sizeof(eq_controls) /
-                        sizeof(control_params); i++) {
+                for (i = 0; i < ARRAY_SIZE(eq_controls); i++) {
 
                         err = add_new_ctl(mixer,
                                 eq_controls[i].kcontrol_new,
@@ -1413,10 +1384,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
                 }
 
                 /* add compressor controls */
-                for (i = 0;
-                        i < sizeof(comp_controls)
-                        / sizeof(control_params);
-                        i++) {
+                for (i = 0; i < ARRAY_SIZE(comp_controls); i++) {
 
                         err = add_new_ctl(mixer,
                                 comp_controls[i].kcontrol_new,