Hello Takashi Iwai,
The patch 481f17c41803: "ALSA: usb-audio: Handle error for the
current selector gracefully" from May 18, 2021, leads to the
following static checker warning:
sound/usb/clock.c:338 __uac_clock_find_source()
error: uninitialized symbol 'cur'.
sound/usb/clock.c
254 static int __uac_clock_find_source(struct snd_usb_audio *chip,
255 const struct audioformat *fmt, int entity_id,
256 unsigned long *visited, bool validate)
257 {
258 union uac23_clock_source_desc *source;
259 union uac23_clock_selector_desc *selector;
260 union uac23_clock_multiplier_desc *multiplier;
261 int ret, i, cur, err, pins, clock_id;
^^^
262 const u8 *sources;
263 int proto = fmt->protocol;
264
265 entity_id &= 0xff;
266
267 if (test_and_set_bit(entity_id, visited)) {
268 usb_audio_warn(chip,
269 "%s(): recursive clock topology detected, id %d.\n",
270 __func__, entity_id);
271 return -EINVAL;
272 }
273
274 /* first, see if the ID we're looking for is a clock source already */
275 source = snd_usb_find_clock_source(chip, entity_id, proto);
276 if (source) {
277 entity_id = GET_VAL(source, proto, bClockID);
278 if (validate && !uac_clock_source_is_valid(chip, fmt,
279 entity_id)) {
280 usb_audio_err(chip,
281 "clock source %d is not valid, cannot use\n",
282 entity_id);
283 return -ENXIO;
284 }
285 return entity_id;
286 }
287
288 selector = snd_usb_find_clock_selector(chip, entity_id, proto);
289 if (selector) {
290 pins = GET_VAL(selector, proto, bNrInPins);
291 clock_id = GET_VAL(selector, proto, bClockID);
292 sources = GET_VAL(selector, proto, baCSourceID);
293
294 if (pins == 1) {
295 ret = 1;
296 goto find_source;
297 }
298
299 /* the entity ID we are looking for is a selector.
300 * find out what it currently selects */
301 ret = uac_clock_selector_get_val(chip, clock_id);
302 if (ret < 0) {
303 if (!chip->autoclock)
304 return ret;
305 goto find_others;
^^^^^^^^^^^^^^^^^
Assume we hit one of these gotos
306 }
307
308 /* Selector values are one-based */
309
310 if (ret > pins || ret < 1) {
311 usb_audio_err(chip,
312 "%s(): selector reported illegal value, id %d, ret %d\n",
313 __func__, clock_id, ret);
314
315 if (!chip->autoclock)
316 return -EINVAL;
317 ret = 0;
318 goto find_others;
^^^^^^^^^^^^^^^^^
319 }
320
321 find_source:
322 cur = ret;
323 ret = __uac_clock_find_source(chip, fmt,
324 sources[ret - 1],
325 visited, validate);
326 if (ret > 0) {
327 err = uac_clock_selector_set_val(chip, entity_id, cur);
328 if (err < 0)
329 return err;
330 }
331
332 if (!validate || ret > 0 || !chip->autoclock)
333 return ret;
334
335 find_others:
336 /* The current clock source is invalid, try others. */
337 for (i = 1; i <= pins; i++) {
338 if (i == cur)
^^^^^^^^
339 continue;
340
341 ret = __uac_clock_find_source(chip, fmt,
342 sources[i - 1],
343
regards,
dan carpenter
