ALSA: usb-audio: Refactoring UAC2/3 clock setup code
authorTakashi Iwai <tiwai@suse.de>
Tue, 18 May 2021 15:21:11 +0000 (17:21 +0200)
committerTakashi Iwai <tiwai@suse.de>
Wed, 19 May 2021 14:22:10 +0000 (16:22 +0200)
This patch just does refactoring of the UAC2/3 clock setup code.
There should be no functional changes.  The major changes are:

* Provide union objects for pointing both UAC2 and UAC3 objects
* Unify clock source, selector and multiplier helper functions
* Unify __uac_clock_find_source() to deal with both UAC2 and UAC3
  equally

Link: https://lore.kernel.org/r/20210518152112.8016-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/usb/clock.c

index 17bbde7..48a79f1 100644 (file)
 #include "clock.h"
 #include "quirks.h"
 
+union uac23_clock_source_desc {
+       struct uac_clock_source_descriptor v2;
+       struct uac3_clock_source_descriptor v3;
+};
+
+union uac23_clock_selector_desc {
+       struct uac_clock_selector_descriptor v2;
+       struct uac3_clock_selector_descriptor v3;
+};
+
+union uac23_clock_multiplier_desc {
+       struct uac_clock_multiplier_descriptor v2;
+       struct uac_clock_multiplier_descriptor v3;
+};
+
+#define GET_VAL(p, proto, field) \
+       ((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
+
 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
-                                bool (*validator)(void *, int), u8 type)
+                                bool (*validator)(void *, int, int),
+                                u8 type, int proto)
 {
        void *cs = NULL;
 
        while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
                                             cs, type))) {
-               if (validator(cs, id))
+               if (validator(cs, id, proto))
                        return cs;
        }
 
        return NULL;
 }
 
-static bool validate_clock_source_v2(void *p, int id)
+static bool validate_clock_source(void *p, int id, int proto)
 {
-       struct uac_clock_source_descriptor *cs = p;
-       return cs->bClockID == id;
-}
+       union uac23_clock_source_desc *cs = p;
 
-static bool validate_clock_source_v3(void *p, int id)
-{
-       struct uac3_clock_source_descriptor *cs = p;
-       return cs->bClockID == id;
+       return GET_VAL(cs, proto, bClockID) == id;
 }
 
-static bool validate_clock_selector_v2(void *p, int id)
+static bool validate_clock_selector(void *p, int id, int proto)
 {
-       struct uac_clock_selector_descriptor *cs = p;
-       return cs->bClockID == id;
-}
+       union uac23_clock_selector_desc *cs = p;
 
-static bool validate_clock_selector_v3(void *p, int id)
-{
-       struct uac3_clock_selector_descriptor *cs = p;
-       return cs->bClockID == id;
+       return GET_VAL(cs, proto, bClockID) == id;
 }
 
-static bool validate_clock_multiplier_v2(void *p, int id)
+static bool validate_clock_multiplier(void *p, int id, int proto)
 {
-       struct uac_clock_multiplier_descriptor *cs = p;
-       return cs->bClockID == id;
-}
+       union uac23_clock_multiplier_desc *cs = p;
 
-static bool validate_clock_multiplier_v3(void *p, int id)
-{
-       struct uac3_clock_multiplier_descriptor *cs = p;
-       return cs->bClockID == id;
+       return GET_VAL(cs, proto, bClockID) == id;
 }
 
-#define DEFINE_FIND_HELPER(name, obj, validator, type)         \
-static obj *name(struct usb_host_interface *iface, int id)     \
-{                                                              \
-       return find_uac_clock_desc(iface, id, validator, type); \
+#define DEFINE_FIND_HELPER(name, obj, validator, type2, type3)         \
+static obj *name(struct snd_usb_audio *chip, int id, int proto)        \
+{                                                                      \
+       return find_uac_clock_desc(chip->ctrl_intf, id, validator,      \
+                                  proto == UAC_VERSION_3 ? (type3) : (type2), \
+                                  proto);                              \
 }
 
 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
-                  struct uac_clock_source_descriptor,
-                  validate_clock_source_v2, UAC2_CLOCK_SOURCE);
-DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
-                  struct uac3_clock_source_descriptor,
-                  validate_clock_source_v3, UAC3_CLOCK_SOURCE);
-
+                  union uac23_clock_source_desc, validate_clock_source,
+                  UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
-                  struct uac_clock_selector_descriptor,
-                  validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
-DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
-                  struct uac3_clock_selector_descriptor,
-                  validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
-
+                  union uac23_clock_selector_desc, validate_clock_selector,
+                  UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
-                  struct uac_clock_multiplier_descriptor,
-                  validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
-DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
-                  struct uac3_clock_multiplier_descriptor,
-                  validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
+                  union uac23_clock_multiplier_desc, validate_clock_multiplier,
+                  UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
 
 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
 {
@@ -159,14 +154,13 @@ static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
        int count;
        unsigned char data;
        struct usb_device *dev = chip->dev;
+       union uac23_clock_source_desc *cs_desc;
 
-       if (fmt->protocol == UAC_VERSION_2) {
-               struct uac_clock_source_descriptor *cs_desc =
-                       snd_usb_find_clock_source(chip->ctrl_intf, source_id);
-
-               if (!cs_desc)
-                       return false;
+       cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
+       if (!cs_desc)
+               return false;
 
+       if (fmt->protocol == UAC_VERSION_2) {
                /*
                 * Assume the clock is valid if clock source supports only one
                 * single sample rate, the terminal is connected directly to it
@@ -175,8 +169,8 @@ static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
                 * reports that clock is invalid.
                 */
                if (fmt->nr_rates == 1 &&
-                   (fmt->clock & 0xff) == cs_desc->bClockID &&
-                   (cs_desc->bmAttributes & 0x3) !=
+                   (fmt->clock & 0xff) == cs_desc->v2.bClockID &&
+                   (cs_desc->v2.bmAttributes & 0x3) !=
                                UAC_CLOCK_SOURCE_TYPE_EXT)
                        return true;
        }
@@ -222,22 +216,16 @@ static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
        unsigned char data;
        struct usb_device *dev = chip->dev;
        u32 bmControls;
+       union uac23_clock_source_desc *cs_desc;
 
-       if (fmt->protocol == UAC_VERSION_3) {
-               struct uac3_clock_source_descriptor *cs_desc =
-                       snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
-
-               if (!cs_desc)
-                       return false;
-               bmControls = le32_to_cpu(cs_desc->bmControls);
-       } else { /* UAC_VERSION_1/2 */
-               struct uac_clock_source_descriptor *cs_desc =
-                       snd_usb_find_clock_source(chip->ctrl_intf, source_id);
+       cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
+       if (!cs_desc)
+               return false;
 
-               if (!cs_desc)
-                       return false;
-               bmControls = cs_desc->bmControls;
-       }
+       if (fmt->protocol == UAC_VERSION_3)
+               bmControls = le32_to_cpu(cs_desc->v3.bmControls);
+       else
+               bmControls = cs_desc->v2.bmControls;
 
        /* If a clock source can't tell us whether it's valid, we assume it is */
        if (!uac_v2v3_control_is_readable(bmControls,
@@ -267,9 +255,12 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
                                   const struct audioformat *fmt, int entity_id,
                                   unsigned long *visited, bool validate)
 {
-       struct uac_clock_source_descriptor *source;
-       struct uac_clock_selector_descriptor *selector;
-       struct uac_clock_multiplier_descriptor *multiplier;
+       union uac23_clock_source_desc *source;
+       union uac23_clock_selector_desc *selector;
+       union uac23_clock_multiplier_desc *multiplier;
+       int ret, i, cur, err, pins, clock_id;
+       const u8 *sources;
+       int proto = fmt->protocol;
 
        entity_id &= 0xff;
 
@@ -281,9 +272,9 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
        }
 
        /* first, see if the ID we're looking for is a clock source already */
-       source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
+       source = snd_usb_find_clock_source(chip, entity_id, proto);
        if (source) {
-               entity_id = source->bClockID;
+               entity_id = GET_VAL(source, proto, bClockID);
                if (validate && !uac_clock_source_is_valid(chip, fmt,
                                                                entity_id)) {
                        usb_audio_err(chip,
@@ -294,27 +285,29 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
                return entity_id;
        }
 
-       selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
+       selector = snd_usb_find_clock_selector(chip, entity_id, proto);
        if (selector) {
-               int ret, i, cur, err;
+               pins = GET_VAL(selector, proto, bNrInPins);
+               clock_id = GET_VAL(selector, proto, bClockID);
+               sources = GET_VAL(selector, proto, baCSourceID);
 
-               if (selector->bNrInPins == 1) {
+               if (pins == 1) {
                        ret = 1;
                        goto find_source;
                }
 
                /* the entity ID we are looking for is a selector.
                 * find out what it currently selects */
-               ret = uac_clock_selector_get_val(chip, selector->bClockID);
+               ret = uac_clock_selector_get_val(chip, clock_id);
                if (ret < 0)
                        return ret;
 
                /* Selector values are one-based */
 
-               if (ret > selector->bNrInPins || ret < 1) {
+               if (ret > pins || ret < 1) {
                        usb_audio_err(chip,
                                "%s(): selector reported illegal value, id %d, ret %d\n",
-                               __func__, selector->bClockID, ret);
+                               __func__, clock_id, ret);
 
                        return -EINVAL;
                }
@@ -322,7 +315,7 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
        find_source:
                cur = ret;
                ret = __uac_clock_find_source(chip, fmt,
-                                             selector->baCSourceID[ret - 1],
+                                             sources[ret - 1],
                                              visited, validate);
                if (ret > 0) {
                        err = uac_clock_selector_set_val(chip, entity_id, cur);
@@ -334,12 +327,12 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
                        return ret;
 
                /* The current clock source is invalid, try others. */
-               for (i = 1; i <= selector->bNrInPins; i++) {
+               for (i = 1; i <= pins; i++) {
                        if (i == cur)
                                continue;
 
                        ret = __uac_clock_find_source(chip, fmt,
-                                                     selector->baCSourceID[i - 1],
+                                                     sources[i - 1],
                                                      visited, true);
                        if (ret < 0)
                                continue;
@@ -358,112 +351,11 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip,
        }
 
        /* FIXME: multipliers only act as pass-thru element for now */
-       multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
+       multiplier = snd_usb_find_clock_multiplier(chip, entity_id, proto);
        if (multiplier)
                return __uac_clock_find_source(chip, fmt,
-                                              multiplier->bCSourceID,
-                                              visited, validate);
-
-       return -EINVAL;
-}
-
-static int __uac3_clock_find_source(struct snd_usb_audio *chip,
-                                   const struct audioformat *fmt, int entity_id,
-                                   unsigned long *visited, bool validate)
-{
-       struct uac3_clock_source_descriptor *source;
-       struct uac3_clock_selector_descriptor *selector;
-       struct uac3_clock_multiplier_descriptor *multiplier;
-
-       entity_id &= 0xff;
-
-       if (test_and_set_bit(entity_id, visited)) {
-               usb_audio_warn(chip,
-                        "%s(): recursive clock topology detected, id %d.\n",
-                        __func__, entity_id);
-               return -EINVAL;
-       }
-
-       /* first, see if the ID we're looking for is a clock source already */
-       source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
-       if (source) {
-               entity_id = source->bClockID;
-               if (validate && !uac_clock_source_is_valid(chip, fmt,
-                                                               entity_id)) {
-                       usb_audio_err(chip,
-                               "clock source %d is not valid, cannot use\n",
-                               entity_id);
-                       return -ENXIO;
-               }
-               return entity_id;
-       }
-
-       selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
-       if (selector) {
-               int ret, i, cur, err;
-
-               /* the entity ID we are looking for is a selector.
-                * find out what it currently selects */
-               ret = uac_clock_selector_get_val(chip, selector->bClockID);
-               if (ret < 0)
-                       return ret;
-
-               /* Selector values are one-based */
-
-               if (ret > selector->bNrInPins || ret < 1) {
-                       usb_audio_err(chip,
-                               "%s(): selector reported illegal value, id %d, ret %d\n",
-                               __func__, selector->bClockID, ret);
-
-                       return -EINVAL;
-               }
-
-               cur = ret;
-               ret = __uac3_clock_find_source(chip, fmt,
-                                              selector->baCSourceID[ret - 1],
+                                              GET_VAL(multiplier, proto, bCSourceID),
                                               visited, validate);
-               if (ret > 0) {
-                       err = uac_clock_selector_set_val(chip, entity_id, cur);
-                       if (err < 0)
-                               return err;
-               }
-
-               if (!validate || ret > 0 || !chip->autoclock)
-                       return ret;
-
-               /* The current clock source is invalid, try others. */
-               for (i = 1; i <= selector->bNrInPins; i++) {
-                       int err;
-
-                       if (i == cur)
-                               continue;
-
-                       ret = __uac3_clock_find_source(chip, fmt,
-                                                      selector->baCSourceID[i - 1],
-                                                      visited, true);
-                       if (ret < 0)
-                               continue;
-
-                       err = uac_clock_selector_set_val(chip, entity_id, i);
-                       if (err < 0)
-                               continue;
-
-                       usb_audio_info(chip,
-                                "found and selected valid clock source %d\n",
-                                ret);
-                       return ret;
-               }
-
-               return -ENXIO;
-       }
-
-       /* FIXME: multipliers only act as pass-thru element for now */
-       multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
-                                                     entity_id);
-       if (multiplier)
-               return __uac3_clock_find_source(chip, fmt,
-                                               multiplier->bCSourceID,
-                                               visited, validate);
 
        return -EINVAL;
 }
@@ -487,10 +379,8 @@ int snd_usb_clock_find_source(struct snd_usb_audio *chip,
 
        switch (fmt->protocol) {
        case UAC_VERSION_2:
-               return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
-                                              validate);
        case UAC_VERSION_3:
-               return __uac3_clock_find_source(chip, fmt, fmt->clock, visited,
+               return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
                                               validate);
        default:
                return -EINVAL;
@@ -593,18 +483,13 @@ int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
        u32 bmControls;
        __le32 data;
        int err;
+       union uac23_clock_source_desc *cs_desc;
 
-       if (fmt->protocol == UAC_VERSION_3) {
-               struct uac3_clock_source_descriptor *cs_desc;
-
-               cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
-               bmControls = le32_to_cpu(cs_desc->bmControls);
-       } else {
-               struct uac_clock_source_descriptor *cs_desc;
-
-               cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
-               bmControls = cs_desc->bmControls;
-       }
+       cs_desc = snd_usb_find_clock_source(chip, clock, fmt->protocol);
+       if (fmt->protocol == UAC_VERSION_3)
+               bmControls = le32_to_cpu(cs_desc->v3.bmControls);
+       else
+               bmControls = cs_desc->v2.bmControls;
 
        writeable = uac_v2v3_control_is_writeable(bmControls,
                                                  UAC2_CS_CONTROL_SAM_FREQ);