[PATCH 4.19 10/38] ALSA: usb-audio: Add clock validity quirk for Denon MC7000/MCX8000

From: Greg Kroah-Hartman
Date: Tue Feb 18 2020 - 14:56:01 EST


From: Alexander Tsoy <alexander@xxxxxxx>

commit 9f35a31283775e6f6af73fb2c95c686a4c0acac7 upstream.

It should be safe to ignore clock validity check result if the following
conditions are met:
- only one single sample rate is supported;
- the terminal is directly connected to the clock source;
- the clock type is internal.

This is to deal with some Denon DJ controllers that always reports that
clock is invalid.

Tested-by: Tobias Oszlanyi <toszlanyi@xxxxxxxx>
Signed-off-by: Alexander Tsoy <alexander@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200212235450.697348-1-alexander@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/usb/clock.c | 91 ++++++++++++++++++++++++++++++++++++-----------------
sound/usb/clock.h | 4 +-
sound/usb/format.c | 3 -
3 files changed, 66 insertions(+), 32 deletions(-)

--- a/sound/usb/clock.c
+++ b/sound/usb/clock.c
@@ -165,8 +165,34 @@ static int uac_clock_selector_set_val(st
return ret;
}

+/*
+ * Assume the clock is valid if clock source supports only one single sample
+ * rate, the terminal is connected directly to it (there is no clock selector)
+ * and clock type is internal. This is to deal with some Denon DJ controllers
+ * that always reports that clock is invalid.
+ */
+static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
+ struct audioformat *fmt,
+ int source_id)
+{
+ 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;
+
+ return (fmt->nr_rates == 1 &&
+ (fmt->clock & 0xff) == cs_desc->bClockID &&
+ (cs_desc->bmAttributes & 0x3) !=
+ UAC_CLOCK_SOURCE_TYPE_EXT);
+ }
+
+ return false;
+}
+
static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
- int protocol,
+ struct audioformat *fmt,
int source_id)
{
int err;
@@ -174,7 +200,7 @@ static bool uac_clock_source_is_valid(st
struct usb_device *dev = chip->dev;
u32 bmControls;

- if (protocol == UAC_VERSION_3) {
+ if (fmt->protocol == UAC_VERSION_3) {
struct uac3_clock_source_descriptor *cs_desc =
snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);

@@ -208,10 +234,14 @@ static bool uac_clock_source_is_valid(st
return false;
}

- return data ? true : false;
+ if (data)
+ return true;
+ else
+ return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
}

-static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
+static int __uac_clock_find_source(struct snd_usb_audio *chip,
+ struct audioformat *fmt, int entity_id,
unsigned long *visited, bool validate)
{
struct uac_clock_source_descriptor *source;
@@ -231,7 +261,7 @@ static int __uac_clock_find_source(struc
source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
if (source) {
entity_id = source->bClockID;
- if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
+ if (validate && !uac_clock_source_is_valid(chip, fmt,
entity_id)) {
usb_audio_err(chip,
"clock source %d is not valid, cannot use\n",
@@ -262,8 +292,9 @@ static int __uac_clock_find_source(struc
}

cur = ret;
- ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
- visited, validate);
+ ret = __uac_clock_find_source(chip, fmt,
+ selector->baCSourceID[ret - 1],
+ visited, validate);
if (!validate || ret > 0 || !chip->autoclock)
return ret;

@@ -274,8 +305,9 @@ static int __uac_clock_find_source(struc
if (i == cur)
continue;

- ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
- visited, true);
+ ret = __uac_clock_find_source(chip, fmt,
+ selector->baCSourceID[i - 1],
+ visited, true);
if (ret < 0)
continue;

@@ -295,14 +327,16 @@ static int __uac_clock_find_source(struc
/* 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, validate);
+ return __uac_clock_find_source(chip, fmt,
+ multiplier->bCSourceID,
+ visited, validate);

return -EINVAL;
}

-static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
- unsigned long *visited, bool validate)
+static int __uac3_clock_find_source(struct snd_usb_audio *chip,
+ struct audioformat *fmt, int entity_id,
+ unsigned long *visited, bool validate)
{
struct uac3_clock_source_descriptor *source;
struct uac3_clock_selector_descriptor *selector;
@@ -321,7 +355,7 @@ static int __uac3_clock_find_source(stru
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, UAC_VERSION_3,
+ if (validate && !uac_clock_source_is_valid(chip, fmt,
entity_id)) {
usb_audio_err(chip,
"clock source %d is not valid, cannot use\n",
@@ -352,7 +386,8 @@ static int __uac3_clock_find_source(stru
}

cur = ret;
- ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
+ ret = __uac3_clock_find_source(chip, fmt,
+ selector->baCSourceID[ret - 1],
visited, validate);
if (!validate || ret > 0 || !chip->autoclock)
return ret;
@@ -364,8 +399,9 @@ static int __uac3_clock_find_source(stru
if (i == cur)
continue;

- ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
- visited, true);
+ ret = __uac3_clock_find_source(chip, fmt,
+ selector->baCSourceID[i - 1],
+ visited, true);
if (ret < 0)
continue;

@@ -386,7 +422,8 @@ static int __uac3_clock_find_source(stru
multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
entity_id);
if (multiplier)
- return __uac3_clock_find_source(chip, multiplier->bCSourceID,
+ return __uac3_clock_find_source(chip, fmt,
+ multiplier->bCSourceID,
visited, validate);

return -EINVAL;
@@ -403,18 +440,18 @@ static int __uac3_clock_find_source(stru
*
* Returns the clock source UnitID (>=0) on success, or an error.
*/
-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
- int entity_id, bool validate)
+int snd_usb_clock_find_source(struct snd_usb_audio *chip,
+ struct audioformat *fmt, bool validate)
{
DECLARE_BITMAP(visited, 256);
memset(visited, 0, sizeof(visited));

- switch (protocol) {
+ switch (fmt->protocol) {
case UAC_VERSION_2:
- return __uac_clock_find_source(chip, entity_id, visited,
+ return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
validate);
case UAC_VERSION_3:
- return __uac3_clock_find_source(chip, entity_id, visited,
+ return __uac3_clock_find_source(chip, fmt, fmt->clock, visited,
validate);
default:
return -EINVAL;
@@ -515,8 +552,7 @@ static int set_sample_rate_v2v3(struct s
* automatic clock selection if the current clock is not
* valid.
*/
- clock = snd_usb_clock_find_source(chip, fmt->protocol,
- fmt->clock, true);
+ clock = snd_usb_clock_find_source(chip, fmt, true);
if (clock < 0) {
/* We did not find a valid clock, but that might be
* because the current sample rate does not match an
@@ -524,8 +560,7 @@ static int set_sample_rate_v2v3(struct s
* and we will do another validation after setting the
* rate.
*/
- clock = snd_usb_clock_find_source(chip, fmt->protocol,
- fmt->clock, false);
+ clock = snd_usb_clock_find_source(chip, fmt, false);
if (clock < 0)
return clock;
}
@@ -591,7 +626,7 @@ static int set_sample_rate_v2v3(struct s

validation:
/* validate clock after rate change */
- if (!uac_clock_source_is_valid(chip, fmt->protocol, clock))
+ if (!uac_clock_source_is_valid(chip, fmt, clock))
return -ENXIO;
return 0;
}
--- a/sound/usb/clock.h
+++ b/sound/usb/clock.h
@@ -6,7 +6,7 @@ int snd_usb_init_sample_rate(struct snd_
struct usb_host_interface *alts,
struct audioformat *fmt, int rate);

-int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
- int entity_id, bool validate);
+int snd_usb_clock_find_source(struct snd_usb_audio *chip,
+ struct audioformat *fmt, bool validate);

#endif /* __USBAUDIO_CLOCK_H */
--- a/sound/usb/format.c
+++ b/sound/usb/format.c
@@ -306,8 +306,7 @@ static int parse_audio_format_rates_v2v3
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->protocol,
- fp->clock, false);
+ int clock = snd_usb_clock_find_source(chip, fp, false);

if (clock < 0) {
dev_err(&dev->dev,