ALSA: usb-audio: UAC2: do clock validity check earlier

Move the check that parse_audio_format_rates_v2() do after receiving the clock source entity ID directly into the find function and add a validation flag to the function. This patch does not introduce any logic flow change. It is provided to allow introducing automatic clock switching easier later. By moving this uac_clock_source_is_valid callsite, 2 additional callsites can be avoided. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: usb-audio: UAC2: do clock validity check earlier
Move the check that parse_audio_format_rates_v2() do after receiving the clock source entity ID directly into the find function and add a validation flag to the function. This patch does not introduce any logic flow change. It is provided to allow introducing automatic clock switching easier later. By moving this uac_clock_source_is_valid callsite, 2 additional callsites can be avoided. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Eldad Zack · Takashi Iwai
1 parent f6a8bc70f8
Showing 3 changed files with 21 additions and 18 deletions Side-by-side Diff
sound/usb/clock.c
sound/usb/clock.h
sound/usb/format.c
@@ -131,7 +131,8 @@
 }
  
 static int __uac_clock_find_source(struct snd_usb_audio *chip,
-				   int entity_id, unsigned long *visited)
+				   int entity_id, unsigned long *visited,
+				   bool validate)
 {
 	struct uac_clock_source_descriptor *source;
 	struct uac_clock_selector_descriptor *selector;
@@ -148,8 +149,15 @@
  
 	/* 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);
-	if (source)
-		return source->bClockID;
+	if (source) {
+		entity_id = source->bClockID;
+		if (validate && !uac_clock_source_is_valid(chip, entity_id)) {
+			snd_printk(KERN_ERR "usb-audio:%d: clock source %d is not valid, cannot use\n",
+				   chip->dev->devnum, entity_id);
+			return -ENXIO;
+		}
+		return entity_id;
+	}
  
 	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
 	if (selector) {
@@ -164,7 +172,7 @@
 		/* Selector values are one-based */
  
 		if (ret > selector->bNrInPins || ret < 1) {
-			printk(KERN_ERR
+			snd_printk(KERN_ERR
 				"%s(): selector reported illegal value, id %d, ret %d\n",
 				__func__, selector->bClockID, ret);
  
  
@@ -172,14 +180,14 @@
 		}
  
 		return __uac_clock_find_source(chip, selector->baCSourceID[ret-1],
-					       visited);
+					       visited, validate);
 	}
  
 	/* FIXME: multipliers only act as pass-thru element for now */
 	multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
 	if (multiplier)
 		return __uac_clock_find_source(chip, multiplier->bCSourceID,
-						visited);
+						visited, validate);
  
 	return -EINVAL;
 }
  
@@ -195,11 +203,12 @@
  *
  * Returns the clock source UnitID (>=0) on success, or an error.
  */
-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id)
+int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
+			      bool validate)
 {
 	DECLARE_BITMAP(visited, 256);
 	memset(visited, 0, sizeof(visited));
-	return __uac_clock_find_source(chip, entity_id, visited);
+	return __uac_clock_find_source(chip, entity_id, visited, validate);
 }
  
 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
  
@@ -275,17 +284,10 @@
 	struct usb_device *dev = chip->dev;
 	__le32 data;
 	int err, cur_rate, prev_rate;
-	int clock = snd_usb_clock_find_source(chip, fmt->clock);
+	int clock = snd_usb_clock_find_source(chip, fmt->clock, true);
  
 	if (clock < 0)
 		return clock;
-
-	if (!uac_clock_source_is_valid(chip, clock)) {
-		/* TODO: should we try to find valid clock setups by ourself? */
-		snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n",
-			   dev->devnum, iface, fmt->altsetting, clock);
-		return -ENXIO;
-	}
  
 	prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
  
@@ -5,7 +5,8 @@
 			     struct usb_host_interface *alts,
 			     struct audioformat *fmt, int rate);
  
-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id);
+int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
+			     bool validate);
  
 #endif /* __USBAUDIO_CLOCK_H */
@@ -280,7 +280,7 @@
 	struct usb_device *dev = chip->dev;
 	unsigned char tmp[2], *data;
 	int nr_triplets, data_size, ret = 0;
-	int clock = snd_usb_clock_find_source(chip, fp->clock);
+	int clock = snd_usb_clock_find_source(chip, fp->clock, false);
  
 	if (clock < 0) {
 		snd_printk(KERN_ERR "%s(): unable to find clock source (clock %d)\n",
...	...	@@ -131,7 +131,8 @@
131	131	}
132	132
133	133	static int __uac_clock_find_source(struct snd_usb_audio *chip,
134		- int entity_id, unsigned long *visited)
	134	+ int entity_id, unsigned long *visited,
	135	+ bool validate)
135	136	{
136	137	struct uac_clock_source_descriptor *source;
137	138	struct uac_clock_selector_descriptor *selector;
...	...	@@ -148,8 +149,15 @@
148	149
149	150	/* first, see if the ID we're looking for is a clock source already */
150	151	source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
151		- if (source)
152		- return source->bClockID;
	152	+ if (source) {
	153	+ entity_id = source->bClockID;
	154	+ if (validate && !uac_clock_source_is_valid(chip, entity_id)) {
	155	+ snd_printk(KERN_ERR "usb-audio:%d: clock source %d is not valid, cannot use\n",
	156	+ chip->dev->devnum, entity_id);
	157	+ return -ENXIO;
	158	+ }
	159	+ return entity_id;
	160	+ }
153	161
154	162	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
155	163	if (selector) {
...	...	@@ -164,7 +172,7 @@
164	172	/* Selector values are one-based */
165	173
166	174	if (ret > selector->bNrInPins \|\| ret < 1) {
167		- printk(KERN_ERR
	175	+ snd_printk(KERN_ERR
168	176	"%s(): selector reported illegal value, id %d, ret %d\n",
169	177	__func__, selector->bClockID, ret);
170	178
171	179
...	...	@@ -172,14 +180,14 @@
172	180	}
173	181
174	182	return __uac_clock_find_source(chip, selector->baCSourceID[ret-1],
175		- visited);
	183	+ visited, validate);
176	184	}
177	185
178	186	/* FIXME: multipliers only act as pass-thru element for now */
179	187	multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
180	188	if (multiplier)
181	189	return __uac_clock_find_source(chip, multiplier->bCSourceID,
182		- visited);
	190	+ visited, validate);
183	191
184	192	return -EINVAL;
185	193	}
186	194
...	...	@@ -195,11 +203,12 @@
195	203	*
196	204	* Returns the clock source UnitID (>=0) on success, or an error.
197	205	*/
198		-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id)
	206	+int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
	207	+ bool validate)
199	208	{
200	209	DECLARE_BITMAP(visited, 256);
201	210	memset(visited, 0, sizeof(visited));
202		- return __uac_clock_find_source(chip, entity_id, visited);
	211	+ return __uac_clock_find_source(chip, entity_id, visited, validate);
203	212	}
204	213
205	214	static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
206	215
...	...	@@ -275,17 +284,10 @@
275	284	struct usb_device *dev = chip->dev;
276	285	__le32 data;
277	286	int err, cur_rate, prev_rate;
278		- int clock = snd_usb_clock_find_source(chip, fmt->clock);
	287	+ int clock = snd_usb_clock_find_source(chip, fmt->clock, true);
279	288
280	289	if (clock < 0)
281	290	return clock;
282		-
283		- if (!uac_clock_source_is_valid(chip, clock)) {
284		- /* TODO: should we try to find valid clock setups by ourself? */
285		- snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n",
286		- dev->devnum, iface, fmt->altsetting, clock);
287		- return -ENXIO;
288		- }
289	291
290	292	prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
291	293
...	...	@@ -5,7 +5,8 @@
5	5	struct usb_host_interface *alts,
6	6	struct audioformat *fmt, int rate);
7	7
8		-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id);
	8	+int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
	9	+ bool validate);
9	10
10	11	#endif /* __USBAUDIO_CLOCK_H */
...	...	@@ -280,7 +280,7 @@
280	280	struct usb_device *dev = chip->dev;
281	281	unsigned char tmp[2], *data;
282	282	int nr_triplets, data_size, ret = 0;
283		- int clock = snd_usb_clock_find_source(chip, fp->clock);
	283	+ int clock = snd_usb_clock_find_source(chip, fp->clock, false);
284	284
285	285	if (clock < 0) {
286	286	snd_printk(KERN_ERR "%s(): unable to find clock source (clock %d)\n",