[PATCH v4 00/10] usb: gadget: audio: Multiple rates, notify

[PATCH v4 00/10] usb: gadget: audio: Multiple rates, notify

[Pavel Hofman]

This series implements:
* Support for multiple rates in the audio gadget
* Notification of gadget-side alsa processes about playback/capture
  start/stop on the host side via Playback/Capture Rate controls.
* Detection of the USB cable disconnection by handling SUSPEND call
  in f_uac1/2. The disconnection generates a stop notification.

Patches for the multirate support, originally authored by Julian Scheel,
were rebased and modified for the current code base. Julian has
acknowledged the presented patches.

The detection of cable disconnection was discussed with dwc2 maintainer
Minas Harutyunyan who confirmed that the suspend event can be used
(https://lore.kernel.org/all/5aada8e3-f385-0589-8d58-187abd1a924d@synopsys.com/T/).
Tests on dwc2 have confirmed reliable detection, the gadget correctly
reports playback/capture stop at cable disconnection.

The start/stop/current rate notification feature is accompanied by
example implementation of audio gadget controller
https://github.com/pavhofman/gaudio_ctl. The controller also handles
debouncing fast start/stop events when USB host audio driver is loaded
and/or audio daemon re/started.

Changes:
--------

v2:
* Fixed compilation of "usb: gadget: f_uac1: Support multiple sampling
  rates" - added changes for CONFIG_GADGET_UAC1

v3:
* Implemented most of changes suggested by John Keeping
* Patches for bInterval calculation moved to a separate patch series
* Patches for stopping substreams moved to a separate patch series
* audio: Replaced deprecated macro S_IRUGO
* u_audio: Moved dynamic srate from params to rtd
* f_uac2: removed current state srates from struct f_uac2_opts, using
  u_audio_get_playback/capture_srate() instead.
* f_uac2: Reworked macros for struct cntrl_ranges_lay3_xxx

v4:
* Fixed the unused-but-set-variable warnings
* Patch "usb: gadget: f_uac2: Rename Clock Sources to fixed names"
  squashed to patch "usb: gadget: f_uac2: Support multiple sampling
  rates"


Julian Scheel (3):
  usb: gadget: u_audio: Support multiple sampling rates
  usb: gadget: f_uac2: Support multiple sampling rates
  usb: gadget: f_uac1: Support multiple sampling rates

Pavel Hofman (7):
  usb: gadget:audio: Replace deprecated macro S_IRUGO
  usb: gadget: u_audio: Move dynamic srate from params to rtd
  usb: gadget: u_audio: Add capture/playback srate getter
  usb: gadget: u_audio: Rate ctl notifies about current srate
    (0=stopped)
  usb: gadget: u_audio: Add suspend call
  usb: gadget: f_uac2: Add suspend callback
  usb: gadget: f_uac1: Add suspend callback

 .../ABI/testing/configfs-usb-gadget-uac1      |   4 +-
 .../ABI/testing/configfs-usb-gadget-uac2      |   4 +-
 Documentation/usb/gadget-testing.rst          |   8 +-
 drivers/usb/gadget/function/f_uac1.c          | 190 ++++++++++++--
 drivers/usb/gadget/function/f_uac2.c          | 207 ++++++++++++---
 drivers/usb/gadget/function/u_audio.c         | 238 ++++++++++++++++--
 drivers/usb/gadget/function/u_audio.h         |  14 +-
 drivers/usb/gadget/function/u_uac1.h          |   5 +-
 drivers/usb/gadget/function/u_uac2.h          |   5 +-
 drivers/usb/gadget/function/uac_common.h      |   9 +
 drivers/usb/gadget/legacy/audio.c             |  78 +++---
 11 files changed, 632 insertions(+), 130 deletions(-)
 create mode 100644 drivers/usb/gadget/function/uac_common.h

-- 
2.25.1

[PATCH v4 01/10] usb: gadget:audio: Replace deprecated macro S_IRUGO

[Pavel Hofman]

Use octal digits as suggested by checkpatch instead of the deprecated
macro.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3: new patch
---
 drivers/usb/gadget/legacy/audio.c | 36 +++++++++++++++----------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index a748ed0842e8..5ec477ffab7f 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -22,32 +22,32 @@ USB_GADGET_COMPOSITE_OPTIONS();
 
 /* Playback(USB-IN) Default Stereo - Fl/Fr */
 static int p_chmask = UAC2_DEF_PCHMASK;
-module_param(p_chmask, uint, S_IRUGO);
+module_param(p_chmask, uint, 0444);
 MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");
 
 /* Playback Default 48 KHz */
 static int p_srate = UAC2_DEF_PSRATE;
-module_param(p_srate, uint, S_IRUGO);
+module_param(p_srate, uint, 0444);
 MODULE_PARM_DESC(p_srate, "Playback Sampling Rate");
 
 /* Playback Default 16bits/sample */
 static int p_ssize = UAC2_DEF_PSSIZE;
-module_param(p_ssize, uint, S_IRUGO);
+module_param(p_ssize, uint, 0444);
 MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");
 
 /* Capture(USB-OUT) Default Stereo - Fl/Fr */
 static int c_chmask = UAC2_DEF_CCHMASK;
-module_param(c_chmask, uint, S_IRUGO);
+module_param(c_chmask, uint, 0444);
 MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");
 
 /* Capture Default 64 KHz */
 static int c_srate = UAC2_DEF_CSRATE;
-module_param(c_srate, uint, S_IRUGO);
+module_param(c_srate, uint, 0444);
 MODULE_PARM_DESC(c_srate, "Capture Sampling Rate");
 
 /* Capture Default 16bits/sample */
 static int c_ssize = UAC2_DEF_CSSIZE;
-module_param(c_ssize, uint, S_IRUGO);
+module_param(c_ssize, uint, 0444);
 MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
 #else
 #ifndef CONFIG_GADGET_UAC1_LEGACY
@@ -55,58 +55,58 @@ MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
 
 /* Playback(USB-IN) Default Stereo - Fl/Fr */
 static int p_chmask = UAC1_DEF_PCHMASK;
-module_param(p_chmask, uint, S_IRUGO);
+module_param(p_chmask, uint, 0444);
 MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");
 
 /* Playback Default 48 KHz */
 static int p_srate = UAC1_DEF_PSRATE;
-module_param(p_srate, uint, S_IRUGO);
+module_param(p_srate, uint, 0444);
 MODULE_PARM_DESC(p_srate, "Playback Sampling Rate");
 
 /* Playback Default 16bits/sample */
 static int p_ssize = UAC1_DEF_PSSIZE;
-module_param(p_ssize, uint, S_IRUGO);
+module_param(p_ssize, uint, 0444);
 MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");
 
 /* Capture(USB-OUT) Default Stereo - Fl/Fr */
 static int c_chmask = UAC1_DEF_CCHMASK;
-module_param(c_chmask, uint, S_IRUGO);
+module_param(c_chmask, uint, 0444);
 MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");
 
 /* Capture Default 48 KHz */
 static int c_srate = UAC1_DEF_CSRATE;
-module_param(c_srate, uint, S_IRUGO);
+module_param(c_srate, uint, 0444);
 MODULE_PARM_DESC(c_srate, "Capture Sampling Rate");
 
 /* Capture Default 16bits/sample */
 static int c_ssize = UAC1_DEF_CSSIZE;
-module_param(c_ssize, uint, S_IRUGO);
+module_param(c_ssize, uint, 0444);
 MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
 #else /* CONFIG_GADGET_UAC1_LEGACY */
 #include "u_uac1_legacy.h"
 
 static char *fn_play = FILE_PCM_PLAYBACK;
-module_param(fn_play, charp, S_IRUGO);
+module_param(fn_play, charp, 0444);
 MODULE_PARM_DESC(fn_play, "Playback PCM device file name");
 
 static char *fn_cap = FILE_PCM_CAPTURE;
-module_param(fn_cap, charp, S_IRUGO);
+module_param(fn_cap, charp, 0444);
 MODULE_PARM_DESC(fn_cap, "Capture PCM device file name");
 
 static char *fn_cntl = FILE_CONTROL;
-module_param(fn_cntl, charp, S_IRUGO);
+module_param(fn_cntl, charp, 0444);
 MODULE_PARM_DESC(fn_cntl, "Control device file name");
 
 static int req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
-module_param(req_buf_size, int, S_IRUGO);
+module_param(req_buf_size, int, 0444);
 MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");
 
 static int req_count = UAC1_REQ_COUNT;
-module_param(req_count, int, S_IRUGO);
+module_param(req_count, int, 0444);
 MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");
 
 static int audio_buf_size = UAC1_AUDIO_BUF_SIZE;
-module_param(audio_buf_size, int, S_IRUGO);
+module_param(audio_buf_size, int, 0444);
 MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
 #endif /* CONFIG_GADGET_UAC1_LEGACY */
 #endif
-- 
2.25.1

[PATCH v4 02/10] usb: gadget: u_audio: Support multiple sampling rates

[Pavel Hofman]

From: Julian Scheel <julian@jusst.de>

Implement support for multiple sampling rates in u_audio part of the
audio gadget. The currently configured rates are exposed through
read-only amixer controls 'Capture Rate' and 'Playback Rate'.

Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3: removed unused variables in u_audio.c
---
 drivers/usb/gadget/function/f_uac1.c     |   2 +
 drivers/usb/gadget/function/f_uac2.c     |   2 +
 drivers/usb/gadget/function/u_audio.c    | 131 +++++++++++++++++++++++
 drivers/usb/gadget/function/u_audio.h    |  10 +-
 drivers/usb/gadget/function/uac_common.h |   9 ++
 5 files changed, 152 insertions(+), 2 deletions(-)
 create mode 100644 drivers/usb/gadget/function/uac_common.h

diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 03f50643fbba..ccb0e4f41e5d 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -1298,6 +1298,7 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	audio->in_ep_maxpsize = le16_to_cpu(as_in_ep_desc.wMaxPacketSize);
 	audio->params.c_chmask = audio_opts->c_chmask;
 	audio->params.c_srate = audio_opts->c_srate;
+	audio->params.c_srates[0] = audio_opts->c_srate;
 	audio->params.c_ssize = audio_opts->c_ssize;
 	if (FUIN_EN(audio_opts)) {
 		audio->params.p_fu.id = USB_IN_FU_ID;
@@ -1310,6 +1311,7 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	}
 	audio->params.p_chmask = audio_opts->p_chmask;
 	audio->params.p_srate = audio_opts->p_srate;
+	audio->params.p_srates[0] = audio_opts->p_srate;
 	audio->params.p_ssize = audio_opts->p_ssize;
 	if (FUOUT_EN(audio_opts)) {
 		audio->params.c_fu.id = USB_OUT_FU_ID;
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 36fa6ef0581b..1334691073a0 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1210,6 +1210,7 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 
 	agdev->params.p_chmask = uac2_opts->p_chmask;
 	agdev->params.p_srate = uac2_opts->p_srate;
+	agdev->params.p_srates[0] = uac2_opts->p_srate;
 	agdev->params.p_ssize = uac2_opts->p_ssize;
 	if (FUIN_EN(uac2_opts)) {
 		agdev->params.p_fu.id = USB_IN_FU_ID;
@@ -1221,6 +1222,7 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	}
 	agdev->params.c_chmask = uac2_opts->c_chmask;
 	agdev->params.c_srate = uac2_opts->c_srate;
+	agdev->params.c_srates[0] = uac2_opts->c_srate;
 	agdev->params.c_ssize = uac2_opts->c_ssize;
 	if (FUOUT_EN(uac2_opts)) {
 		agdev->params.c_fu.id = USB_OUT_FU_ID;
diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index 4561d7a183ff..50ccb36d22d7 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -32,6 +32,7 @@ enum {
 	UAC_P_PITCH_CTRL,
 	UAC_MUTE_CTRL,
 	UAC_VOLUME_CTRL,
+	UAC_RATE_CTRL,
 };
 
 /* Runtime data params for one stream */
@@ -62,6 +63,8 @@ struct uac_rtd_params {
   s16 volume;
   int mute;
 
+	struct snd_kcontrol *snd_kctl_rate; /* read-only current rate */
+
   spinlock_t lock; /* lock for control transfers */
 
 };
@@ -493,6 +496,44 @@ static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
 		dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
 }
 
+int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
+{
+	struct uac_params *params = &audio_dev->params;
+	int i;
+
+	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
+	for (i = 0; i < UAC_MAX_RATES; i++) {
+		if (params->c_srates[i] == srate) {
+			params->c_srate = srate;
+			return 0;
+		}
+		if (params->c_srates[i] == 0)
+			break;
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(u_audio_set_capture_srate);
+
+int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
+{
+	struct uac_params *params = &audio_dev->params;
+	int i;
+
+	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
+	for (i = 0; i < UAC_MAX_RATES; i++) {
+		if (params->p_srates[i] == srate) {
+			params->p_srate = srate;
+			return 0;
+		}
+		if (params->p_srates[i] == 0)
+			break;
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(u_audio_set_playback_srate);
+
 int u_audio_start_capture(struct g_audio *audio_dev)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
@@ -504,6 +545,7 @@ int u_audio_start_capture(struct g_audio *audio_dev)
 	struct uac_params *params = &audio_dev->params;
 	int req_len, i;
 
+	dev_dbg(dev, "start capture with rate %d\n", params->c_srate);
 	ep = audio_dev->out_ep;
 	prm = &uac->c_prm;
 	config_ep_by_speed(gadget, &audio_dev->func, ep);
@@ -596,6 +638,7 @@ int u_audio_start_playback(struct g_audio *audio_dev)
 	int req_len, i;
 	unsigned int p_pktsize;
 
+	dev_dbg(dev, "start playback with rate %d\n", params->p_srate);
 	ep = audio_dev->in_ep;
 	prm = &uac->p_prm;
 	config_ep_by_speed(gadget, &audio_dev->func, ep);
@@ -943,6 +986,68 @@ static int u_audio_volume_put(struct snd_kcontrol *kcontrol,
 	return change;
 }
 
+static int get_max_srate(const int *srates)
+{
+	int i, max_srate = 0;
+
+	for (i = 0; i < UAC_MAX_RATES; i++) {
+		if (srates[i] == 0)
+			break;
+		if (srates[i] > max_srate)
+			max_srate = srates[i];
+	}
+	return max_srate;
+}
+
+static int get_min_srate(const int *srates)
+{
+	int i, min_srate = INT_MAX;
+
+	for (i = 0; i < UAC_MAX_RATES; i++) {
+		if (srates[i] == 0)
+			break;
+		if (srates[i] < min_srate)
+			min_srate = srates[i];
+	}
+	return min_srate;
+}
+
+static int u_audio_rate_info(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_info *uinfo)
+{
+	const int *srates;
+	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev = uac->audio_dev;
+	struct uac_params *params = &audio_dev->params;
+
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+
+	if (prm == &uac->c_prm)
+		srates = params->c_srates;
+	else
+		srates = params->p_srates;
+	uinfo->value.integer.min = get_min_srate(srates);
+	uinfo->value.integer.max = get_max_srate(srates);
+	return 0;
+}
+
+static int u_audio_rate_get(struct snd_kcontrol *kcontrol,
+						 struct snd_ctl_elem_value *ucontrol)
+{
+	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev = uac->audio_dev;
+	struct uac_params *params = &audio_dev->params;
+
+	if (prm == &uac->c_prm)
+		ucontrol->value.integer.value[0] = params->c_srate;
+	else
+		ucontrol->value.integer.value[0] = params->p_srate;
+
+	return 0;
+}
 
 static struct snd_kcontrol_new u_audio_controls[]  = {
   [UAC_FBACK_CTRL] {
@@ -973,6 +1078,13 @@ static struct snd_kcontrol_new u_audio_controls[]  = {
 		.get =		u_audio_volume_get,
 		.put =		u_audio_volume_put,
 	},
+	[UAC_RATE_CTRL] {
+		.iface =	SNDRV_CTL_ELEM_IFACE_PCM,
+		.name =		"", /* will be filled later */
+		.access =	SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+		.info =		u_audio_rate_info,
+		.get =		u_audio_rate_get,
+	},
 };
 
 int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
@@ -1186,6 +1298,25 @@ int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
 			prm->volume_min = fu->volume_min;
 			prm->volume_res = fu->volume_res;
 		}
+
+		/* Add rate control */
+		snprintf(ctrl_name, sizeof(ctrl_name),
+				"%s Rate", direction);
+		u_audio_controls[UAC_RATE_CTRL].name = ctrl_name;
+
+		kctl = snd_ctl_new1(&u_audio_controls[UAC_RATE_CTRL], prm);
+		if (!kctl) {
+			err = -ENOMEM;
+			goto snd_fail;
+		}
+
+		kctl->id.device = pcm->device;
+		kctl->id.subdevice = 0;
+
+		err = snd_ctl_add(card, kctl);
+		if (err < 0)
+			goto snd_fail;
+		prm->snd_kctl_rate = kctl;
 	}
 
 	strscpy(card->driver, card_name, sizeof(card->driver));
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
index 8dfdae1721cd..76b5b8169444 100644
--- a/drivers/usb/gadget/function/u_audio.h
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -10,6 +10,7 @@
 #define __U_AUDIO_H
 
 #include <linux/usb/composite.h>
+#include "uac_common.h"
 
 /*
  * Same maximum frequency deviation on the slower side as in
@@ -40,13 +41,15 @@ struct uac_fu_params {
 struct uac_params {
 	/* playback */
 	int p_chmask;	/* channel mask */
-	int p_srate;	/* rate in Hz */
+	int p_srates[UAC_MAX_RATES];	/* available rates in Hz (0 terminated list) */
+	int p_srate;	/* selected rate in Hz */
 	int p_ssize;	/* sample size */
 	struct uac_fu_params p_fu;	/* Feature Unit parameters */
 
 	/* capture */
 	int c_chmask;	/* channel mask */
-	int c_srate;	/* rate in Hz */
+	int c_srates[UAC_MAX_RATES];	/* available rates in Hz (0 terminated list) */
+	int c_srate;	/* selected rate in Hz */
 	int c_ssize;	/* sample size */
 	struct uac_fu_params c_fu;	/* Feature Unit parameters */
 
@@ -117,6 +120,9 @@ void u_audio_stop_capture(struct g_audio *g_audio);
 int u_audio_start_playback(struct g_audio *g_audio);
 void u_audio_stop_playback(struct g_audio *g_audio);
 
+int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate);
+int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate);
+
 int u_audio_get_volume(struct g_audio *g_audio, int playback, s16 *val);
 int u_audio_set_volume(struct g_audio *g_audio, int playback, s16 val);
 int u_audio_get_mute(struct g_audio *g_audio, int playback, int *val);
diff --git a/drivers/usb/gadget/function/uac_common.h b/drivers/usb/gadget/function/uac_common.h
new file mode 100644
index 000000000000..3ecf89d6e814
--- /dev/null
+++ b/drivers/usb/gadget/function/uac_common.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ */
+
+#ifndef UAC_COMMON_H
+#define UAC_COMMON_H
+
+#define UAC_MAX_RATES 10 /* maximum number of rates configurable by f_uac1/2 */
+#endif
-- 
2.25.1

[PATCH v4 03/10] usb: gadget: u_audio: Move dynamic srate from params to rtd

[Pavel Hofman]

Parameters uac_params.p_srate/c_srate are dynamic now and are not part
of parametric configuration anymore. Move them to the
runtime struct uac_rtd_params for each stream.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Suggested-by: John Keeping <john@metanate.com>
---
v3: new patch

v4: added Suggested-by to commit msg
---
 drivers/usb/gadget/function/f_uac1.c  |  2 -
 drivers/usb/gadget/function/f_uac2.c  |  2 -
 drivers/usb/gadget/function/u_audio.c | 68 ++++++++++++++-------------
 drivers/usb/gadget/function/u_audio.h |  4 +-
 4 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index ccb0e4f41e5d..0397b27df42e 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -1297,7 +1297,6 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	audio->out_ep_maxpsize = le16_to_cpu(as_out_ep_desc.wMaxPacketSize);
 	audio->in_ep_maxpsize = le16_to_cpu(as_in_ep_desc.wMaxPacketSize);
 	audio->params.c_chmask = audio_opts->c_chmask;
-	audio->params.c_srate = audio_opts->c_srate;
 	audio->params.c_srates[0] = audio_opts->c_srate;
 	audio->params.c_ssize = audio_opts->c_ssize;
 	if (FUIN_EN(audio_opts)) {
@@ -1310,7 +1309,6 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 		audio->params.p_fu.volume_res = audio_opts->p_volume_res;
 	}
 	audio->params.p_chmask = audio_opts->p_chmask;
-	audio->params.p_srate = audio_opts->p_srate;
 	audio->params.p_srates[0] = audio_opts->p_srate;
 	audio->params.p_ssize = audio_opts->p_ssize;
 	if (FUOUT_EN(audio_opts)) {
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 1334691073a0..e518f210968c 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1209,7 +1209,6 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	agdev->gadget = gadget;
 
 	agdev->params.p_chmask = uac2_opts->p_chmask;
-	agdev->params.p_srate = uac2_opts->p_srate;
 	agdev->params.p_srates[0] = uac2_opts->p_srate;
 	agdev->params.p_ssize = uac2_opts->p_ssize;
 	if (FUIN_EN(uac2_opts)) {
@@ -1221,7 +1220,6 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		agdev->params.p_fu.volume_res = uac2_opts->p_volume_res;
 	}
 	agdev->params.c_chmask = uac2_opts->c_chmask;
-	agdev->params.c_srate = uac2_opts->c_srate;
 	agdev->params.c_srates[0] = uac2_opts->c_srate;
 	agdev->params.c_ssize = uac2_opts->c_ssize;
 	if (FUOUT_EN(uac2_opts)) {
diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index 50ccb36d22d7..dce894dcae07 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -64,6 +64,7 @@ struct uac_rtd_params {
   int mute;
 
 	struct snd_kcontrol *snd_kctl_rate; /* read-only current rate */
+	int srate; /* selected samplerate */
 
   spinlock_t lock; /* lock for control transfers */
 
@@ -153,8 +154,6 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 	struct snd_pcm_runtime *runtime;
 	struct uac_rtd_params *prm = req->context;
 	struct snd_uac_chip *uac = prm->uac;
-	struct g_audio *audio_dev = uac->audio_dev;
-	struct uac_params *params = &audio_dev->params;
 	unsigned int frames, p_pktsize;
 	unsigned long long pitched_rate_mil, p_pktsize_residue_mil,
 			residue_frames_mil, div_result;
@@ -199,15 +198,14 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 		 */
 		unsigned long long p_interval_mil = uac->p_interval * 1000000ULL;
 
-		pitched_rate_mil = (unsigned long long)
-				params->p_srate * prm->pitch;
+		pitched_rate_mil = (unsigned long long) prm->srate * prm->pitch;
 		div_result = pitched_rate_mil;
 		do_div(div_result, uac->p_interval);
 		do_div(div_result, 1000000);
 		frames = (unsigned int) div_result;
 
 		pr_debug("p_srate %d, pitch %d, interval_mil %llu, frames %d\n",
-				params->p_srate, prm->pitch, p_interval_mil, frames);
+				prm->srate, prm->pitch, p_interval_mil, frames);
 
 		p_pktsize = min_t(unsigned int,
 					uac->p_framesize * frames,
@@ -284,7 +282,6 @@ static void u_audio_iso_fback_complete(struct usb_ep *ep,
 	struct uac_rtd_params *prm = req->context;
 	struct snd_uac_chip *uac = prm->uac;
 	struct g_audio *audio_dev = uac->audio_dev;
-	struct uac_params *params = &audio_dev->params;
 	int status = req->status;
 
 	/* i/f shutting down */
@@ -306,7 +303,7 @@ static void u_audio_iso_fback_complete(struct usb_ep *ep,
 			__func__, status, req->actual, req->length);
 
 	u_audio_set_fback_frequency(audio_dev->gadget->speed, audio_dev->out_ep,
-				    params->c_srate, prm->pitch,
+				    prm->srate, prm->pitch,
 				    req->buf);
 
 	if (usb_ep_queue(ep, req, GFP_ATOMIC))
@@ -390,16 +387,14 @@ static int uac_pcm_open(struct snd_pcm_substream *substream)
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct g_audio *audio_dev;
 	struct uac_params *params;
+	struct uac_rtd_params *prm;
 	int p_ssize, c_ssize;
-	int p_srate, c_srate;
 	int p_chmask, c_chmask;
 
 	audio_dev = uac->audio_dev;
 	params = &audio_dev->params;
 	p_ssize = params->p_ssize;
 	c_ssize = params->c_ssize;
-	p_srate = params->p_srate;
-	c_srate = params->c_srate;
 	p_chmask = params->p_chmask;
 	c_chmask = params->c_chmask;
 	uac->p_residue_mil = 0;
@@ -407,19 +402,18 @@ static int uac_pcm_open(struct snd_pcm_substream *substream)
 	runtime->hw = uac_pcm_hardware;
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		runtime->hw.rate_min = p_srate;
 		runtime->hw.formats = uac_ssize_to_fmt(p_ssize);
 		runtime->hw.channels_min = num_channels(p_chmask);
-		runtime->hw.period_bytes_min = 2 * uac->p_prm.max_psize
-						/ runtime->hw.periods_min;
+		prm = &uac->p_prm;
 	} else {
-		runtime->hw.rate_min = c_srate;
 		runtime->hw.formats = uac_ssize_to_fmt(c_ssize);
 		runtime->hw.channels_min = num_channels(c_chmask);
-		runtime->hw.period_bytes_min = 2 * uac->c_prm.max_psize
-						/ runtime->hw.periods_min;
+		prm = &uac->c_prm;
 	}
 
+	runtime->hw.period_bytes_min = 2 * prm->max_psize
+					/ runtime->hw.periods_min;
+	runtime->hw.rate_min = prm->srate;
 	runtime->hw.rate_max = runtime->hw.rate_min;
 	runtime->hw.channels_max = runtime->hw.channels_min;
 
@@ -499,12 +493,18 @@ static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
 int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
 {
 	struct uac_params *params = &audio_dev->params;
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct uac_rtd_params *prm;
 	int i;
+	unsigned long flags;
 
 	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
+	prm = &uac->c_prm;
 	for (i = 0; i < UAC_MAX_RATES; i++) {
 		if (params->c_srates[i] == srate) {
-			params->c_srate = srate;
+			spin_lock_irqsave(&prm->lock, flags);
+			prm->srate = srate;
+			spin_unlock_irqrestore(&prm->lock, flags);
 			return 0;
 		}
 		if (params->c_srates[i] == 0)
@@ -518,12 +518,18 @@ EXPORT_SYMBOL_GPL(u_audio_set_capture_srate);
 int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
 {
 	struct uac_params *params = &audio_dev->params;
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct uac_rtd_params *prm;
 	int i;
+	unsigned long flags;
 
 	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
+	prm = &uac->p_prm;
 	for (i = 0; i < UAC_MAX_RATES; i++) {
 		if (params->p_srates[i] == srate) {
-			params->p_srate = srate;
+			spin_lock_irqsave(&prm->lock, flags);
+			prm->srate = srate;
+			spin_unlock_irqrestore(&prm->lock, flags);
 			return 0;
 		}
 		if (params->p_srates[i] == 0)
@@ -545,9 +551,9 @@ int u_audio_start_capture(struct g_audio *audio_dev)
 	struct uac_params *params = &audio_dev->params;
 	int req_len, i;
 
-	dev_dbg(dev, "start capture with rate %d\n", params->c_srate);
-	ep = audio_dev->out_ep;
 	prm = &uac->c_prm;
+	dev_dbg(dev, "start capture with rate %d\n", prm->srate);
+	ep = audio_dev->out_ep;
 	config_ep_by_speed(gadget, &audio_dev->func, ep);
 	req_len = ep->maxpacket;
 
@@ -604,7 +610,7 @@ int u_audio_start_capture(struct g_audio *audio_dev)
 	 */
 	prm->pitch = 1000000;
 	u_audio_set_fback_frequency(audio_dev->gadget->speed, ep,
-				    params->c_srate, prm->pitch,
+				    prm->srate, prm->pitch,
 				    req_fback->buf);
 
 	if (usb_ep_queue(ep_fback, req_fback, GFP_ATOMIC))
@@ -638,9 +644,9 @@ int u_audio_start_playback(struct g_audio *audio_dev)
 	int req_len, i;
 	unsigned int p_pktsize;
 
-	dev_dbg(dev, "start playback with rate %d\n", params->p_srate);
-	ep = audio_dev->in_ep;
 	prm = &uac->p_prm;
+	dev_dbg(dev, "start playback with rate %d\n", prm->srate);
+	ep = audio_dev->in_ep;
 	config_ep_by_speed(gadget, &audio_dev->func, ep);
 
 	ep_desc = ep->desc;
@@ -661,7 +667,7 @@ int u_audio_start_playback(struct g_audio *audio_dev)
 	uac->p_interval = factor / (1 << (ep_desc->bInterval - 1));
 	p_pktsize = min_t(unsigned int,
 				uac->p_framesize *
-					(params->p_srate / uac->p_interval),
+					(prm->srate / uac->p_interval),
 				ep->maxpacket);
 
 	req_len = p_pktsize;
@@ -1037,15 +1043,11 @@ static int u_audio_rate_get(struct snd_kcontrol *kcontrol,
 						 struct snd_ctl_elem_value *ucontrol)
 {
 	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
-	struct snd_uac_chip *uac = prm->uac;
-	struct g_audio *audio_dev = uac->audio_dev;
-	struct uac_params *params = &audio_dev->params;
-
-	if (prm == &uac->c_prm)
-		ucontrol->value.integer.value[0] = params->c_srate;
-	else
-		ucontrol->value.integer.value[0] = params->p_srate;
+	unsigned long flags;
 
+	spin_lock_irqsave(&prm->lock, flags);
+	ucontrol->value.integer.value[0] = prm->srate;
+	spin_unlock_irqrestore(&prm->lock, flags);
 	return 0;
 }
 
@@ -1117,6 +1119,7 @@ int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
     spin_lock_init(&prm->lock);
     uac->c_prm.uac = uac;
 		prm->max_psize = g_audio->out_ep_maxpsize;
+		prm->srate = params->c_srates[0];
 
 		prm->reqs = kcalloc(params->req_number,
 				    sizeof(struct usb_request *),
@@ -1141,6 +1144,7 @@ int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
 		spin_lock_init(&prm->lock);
 		uac->p_prm.uac = uac;
 		prm->max_psize = g_audio->in_ep_maxpsize;
+		prm->srate = params->p_srates[0];
 
 		prm->reqs = kcalloc(params->req_number,
 				    sizeof(struct usb_request *),
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
index 76b5b8169444..84579fe81b92 100644
--- a/drivers/usb/gadget/function/u_audio.h
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -42,17 +42,17 @@ struct uac_params {
 	/* playback */
 	int p_chmask;	/* channel mask */
 	int p_srates[UAC_MAX_RATES];	/* available rates in Hz (0 terminated list) */
-	int p_srate;	/* selected rate in Hz */
 	int p_ssize;	/* sample size */
 	struct uac_fu_params p_fu;	/* Feature Unit parameters */
 
 	/* capture */
 	int c_chmask;	/* channel mask */
 	int c_srates[UAC_MAX_RATES];	/* available rates in Hz (0 terminated list) */
-	int c_srate;	/* selected rate in Hz */
 	int c_ssize;	/* sample size */
 	struct uac_fu_params c_fu;	/* Feature Unit parameters */
 
+	/* rates are dynamic, in uac_rtd_params */
+
 	int req_number; /* number of preallocated requests */
 	int fb_max;	/* upper frequency drift feedback limit per-mil */
 };
-- 
2.25.1

[PATCH v4 04/10] usb: gadget: u_audio: Add capture/playback srate getter

[Pavel Hofman]

UAC1/UAC2 functions will need to query u_audio about the currently set
srate. Add the getter functions.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3: new patch
---
 drivers/usb/gadget/function/u_audio.c | 28 +++++++++++++++++++++++++++
 drivers/usb/gadget/function/u_audio.h |  2 ++
 2 files changed, 30 insertions(+)

diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index dce894dcae07..283a449a9538 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -515,6 +515,20 @@ int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
 }
 EXPORT_SYMBOL_GPL(u_audio_set_capture_srate);
 
+int u_audio_get_capture_srate(struct g_audio *audio_dev, u32 *val)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct uac_rtd_params *prm;
+	unsigned long flags;
+
+	prm = &uac->c_prm;
+	spin_lock_irqsave(&prm->lock, flags);
+	*val = prm->srate;
+	spin_unlock_irqrestore(&prm->lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(u_audio_get_capture_srate);
+
 int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
 {
 	struct uac_params *params = &audio_dev->params;
@@ -540,6 +554,20 @@ int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
 }
 EXPORT_SYMBOL_GPL(u_audio_set_playback_srate);
 
+int u_audio_get_playback_srate(struct g_audio *audio_dev, u32 *val)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct uac_rtd_params *prm;
+	unsigned long flags;
+
+	prm = &uac->p_prm;
+	spin_lock_irqsave(&prm->lock, flags);
+	*val = prm->srate;
+	spin_unlock_irqrestore(&prm->lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(u_audio_get_playback_srate);
+
 int u_audio_start_capture(struct g_audio *audio_dev)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
index 84579fe81b92..5e6ed0f31cc3 100644
--- a/drivers/usb/gadget/function/u_audio.h
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -120,7 +120,9 @@ void u_audio_stop_capture(struct g_audio *g_audio);
 int u_audio_start_playback(struct g_audio *g_audio);
 void u_audio_stop_playback(struct g_audio *g_audio);
 
+int u_audio_get_capture_srate(struct g_audio *audio_dev, u32 *val);
 int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate);
+int u_audio_get_playback_srate(struct g_audio *audio_dev, u32 *val);
 int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate);
 
 int u_audio_get_volume(struct g_audio *g_audio, int playback, s16 *val);
-- 
2.25.1

[PATCH v4 05/10] usb: gadget: f_uac2: Support multiple sampling rates

[Pavel Hofman]

From: Julian Scheel <julian@jusst.de>

A list of sampling rates can be specified via configfs. All enabled
sampling rates are sent to the USB host on request. When the host
selects a sampling rate, the internal active rate (stored in
struct f_uac2) is updated.

The gadget no longer supports only one frequency. Therefore USB strings
corresponding to the clock sources are renamed from specific Hz value to
general names Input clock/Output clock.

Config strings with single value stay compatible with the previous
version.

Multiple samplerates passed as configuration arrays to g_audio module
when built for f_uac2.

Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3:
* audio.c: fixed unused variables for CONFIG_UAC1 variants
* audio: used 0444 instead of S_IRUGO
* f_uac2: renamed ctl_id -> clock_id + added explaining
  comment
* f_uac2: removed current state srates from struct f_uac2_opts, using
  u_audio_get_playback/capture_srate() instead.
* f_uac2: renamed UAC_RATE2_ATTRIBUTE -> UAC2_RATE_ATTRIBUTE, moved from
  u_uac2.h to f_uac2.c
* renamed confusing cntrl_range_lay3 to cntrl_subrange_lay3
* struct cntrl_ranges_lay3_xxx is created with DECLARE_UAC2_CNTRL_RANGES_LAY3
* fixed ranges_size calculation, renamed to specific ranges_lay3_size
* updated commit message

v3 patch "usb: gadget: f_uac2: Rename Clock Sources to fixed names":
* Renamed commit message
* Corrected STR_CLKSRC_IN/OUT capitalization

v4:
* patch "usb: gadget: f_uac2: Rename Clock Sources to fixed names" squashed to
  this patch, which also resolved unused-but-set-variable warning.
* updated commit msg
---
 .../ABI/testing/configfs-usb-gadget-uac2      |   4 +-
 Documentation/usb/gadget-testing.rst          |   4 +-
 drivers/usb/gadget/function/f_uac2.c          | 198 ++++++++++++++----
 drivers/usb/gadget/function/u_uac2.h          |   5 +-
 drivers/usb/gadget/legacy/audio.c             |  25 ++-
 5 files changed, 182 insertions(+), 54 deletions(-)

diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac2 b/Documentation/ABI/testing/configfs-usb-gadget-uac2
index 7fb3dbe26857..9d2f59ab9701 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uac2
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uac2
@@ -6,7 +6,7 @@ Description:
 
 		=====================	=======================================
 		c_chmask		capture channel mask
-		c_srate			capture sampling rate
+		c_srate			list of capture sampling rates (comma-separated)
 		c_ssize			capture sample size (bytes)
 		c_sync			capture synchronization type
 					(async/adaptive)
@@ -20,7 +20,7 @@ Description:
 					(in 1/256 dB)
 		fb_max			maximum extra bandwidth in async mode
 		p_chmask		playback channel mask
-		p_srate			playback sampling rate
+		p_srate			list of playback sampling rates (comma-separated)
 		p_ssize			playback sample size (bytes)
 		p_mute_present		playback mute control enable
 		p_volume_present	playback volume control enable
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
index cbbd948c626f..419f6e5e890a 100644
--- a/Documentation/usb/gadget-testing.rst
+++ b/Documentation/usb/gadget-testing.rst
@@ -726,7 +726,7 @@ The uac2 function provides these attributes in its function directory:
 
 	================ ====================================================
 	c_chmask         capture channel mask
-	c_srate          capture sampling rate
+	c_srate          list of capture sampling rates (comma-separated)
 	c_ssize          capture sample size (bytes)
 	c_sync           capture synchronization type (async/adaptive)
 	c_mute_present   capture mute control enable
@@ -736,7 +736,7 @@ The uac2 function provides these attributes in its function directory:
 	c_volume_res     capture volume control resolution (in 1/256 dB)
 	fb_max           maximum extra bandwidth in async mode
 	p_chmask         playback channel mask
-	p_srate          playback sampling rate
+	p_srate          list of playback sampling rates (comma-separated)
 	p_ssize          playback sample size (bytes)
 	p_mute_present   playback mute control enable
 	p_volume_present playback volume control enable
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index e518f210968c..058a6a0b5444 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -70,6 +70,8 @@ struct f_uac2 {
 	/* Interrupt IN endpoint of AC interface */
 	struct usb_ep	*int_ep;
 	atomic_t	int_count;
+	/* transient state, only valid during handling of a single control request */
+	int clock_id;
 };
 
 static inline struct f_uac2 *func_to_uac2(struct usb_function *f)
@@ -104,14 +106,11 @@ enum {
 	STR_AS_IN_ALT1,
 };
 
-static char clksrc_in[8];
-static char clksrc_out[8];
-
 static struct usb_string strings_fn[] = {
 	[STR_ASSOC].s = "Source/Sink",
 	[STR_IF_CTRL].s = "Topology Control",
-	[STR_CLKSRC_IN].s = clksrc_in,
-	[STR_CLKSRC_OUT].s = clksrc_out,
+	[STR_CLKSRC_IN].s = "Input Clock",
+	[STR_CLKSRC_OUT].s = "Output Clock",
 	[STR_USB_IT].s = "USBH Out",
 	[STR_IO_IT].s = "USBD Out",
 	[STR_USB_OT].s = "USBH In",
@@ -166,7 +165,7 @@ static struct uac_clock_source_descriptor in_clk_src_desc = {
 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
 	/* .bClockID = DYNAMIC */
 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
-	.bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
+	.bmControls = (CONTROL_RDWR << CLK_FREQ_CTRL),
 	.bAssocTerminal = 0,
 };
 
@@ -178,7 +177,7 @@ static struct uac_clock_source_descriptor out_clk_src_desc = {
 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
 	/* .bClockID = DYNAMIC */
 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
-	.bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
+	.bmControls = (CONTROL_RDWR << CLK_FREQ_CTRL),
 	.bAssocTerminal = 0,
 };
 
@@ -634,13 +633,36 @@ struct cntrl_cur_lay3 {
 	__le32	dCUR;
 };
 
-struct cntrl_range_lay3 {
-	__le16	wNumSubRanges;
+struct cntrl_subrange_lay3 {
 	__le32	dMIN;
 	__le32	dMAX;
 	__le32	dRES;
 } __packed;
 
+#define ranges_lay3_size(c) (sizeof(c.wNumSubRanges) + c.wNumSubRanges	\
+		* sizeof(struct cntrl_subrange_lay3))
+
+#define DECLARE_UAC2_CNTRL_RANGES_LAY3(k, n)		\
+	struct cntrl_ranges_lay3_##k {			\
+	__le16	wNumSubRanges;				\
+	struct cntrl_subrange_lay3 r[n];		\
+} __packed
+
+DECLARE_UAC2_CNTRL_RANGES_LAY3(srates, UAC_MAX_RATES);
+
+static int get_max_srate(const int *srates)
+{
+	int i, max_srate = 0;
+
+	for (i = 0; i < UAC_MAX_RATES; i++) {
+		if (srates[i] == 0)
+			break;
+		if (srates[i] > max_srate)
+			max_srate = srates[i];
+	}
+	return max_srate;
+}
+
 static int set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 	struct usb_endpoint_descriptor *ep_desc,
 	enum usb_device_speed speed, bool is_playback)
@@ -667,11 +689,11 @@ static int set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 
 	if (is_playback) {
 		chmask = uac2_opts->p_chmask;
-		srate = uac2_opts->p_srate;
+		srate = get_max_srate(uac2_opts->p_srates);
 		ssize = uac2_opts->p_ssize;
 	} else {
 		chmask = uac2_opts->c_chmask;
-		srate = uac2_opts->c_srate;
+		srate = get_max_srate(uac2_opts->c_srates);
 		ssize = uac2_opts->c_ssize;
 	}
 
@@ -912,10 +934,10 @@ static int afunc_validate_opts(struct g_audio *agdev, struct device *dev)
 	} else if ((opts->c_ssize < 1) || (opts->c_ssize > 4)) {
 		dev_err(dev, "Error: incorrect capture sample size\n");
 		return -EINVAL;
-	} else if (!opts->p_srate) {
+	} else if (!opts->p_srates[0]) {
 		dev_err(dev, "Error: incorrect playback sampling rate\n");
 		return -EINVAL;
-	} else if (!opts->c_srate) {
+	} else if (!opts->c_srates[0]) {
 		dev_err(dev, "Error: incorrect capture sampling rate\n");
 		return -EINVAL;
 	}
@@ -1037,9 +1059,6 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		*bma = cpu_to_le32(control);
 	}
 
-	snprintf(clksrc_in, sizeof(clksrc_in), "%uHz", uac2_opts->p_srate);
-	snprintf(clksrc_out, sizeof(clksrc_out), "%uHz", uac2_opts->c_srate);
-
 	ret = usb_interface_id(cfg, fn);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
@@ -1209,7 +1228,8 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	agdev->gadget = gadget;
 
 	agdev->params.p_chmask = uac2_opts->p_chmask;
-	agdev->params.p_srates[0] = uac2_opts->p_srate;
+	memcpy(agdev->params.p_srates, uac2_opts->p_srates,
+			sizeof(agdev->params.p_srates));
 	agdev->params.p_ssize = uac2_opts->p_ssize;
 	if (FUIN_EN(uac2_opts)) {
 		agdev->params.p_fu.id = USB_IN_FU_ID;
@@ -1220,7 +1240,8 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		agdev->params.p_fu.volume_res = uac2_opts->p_volume_res;
 	}
 	agdev->params.c_chmask = uac2_opts->c_chmask;
-	agdev->params.c_srates[0] = uac2_opts->c_srate;
+	memcpy(agdev->params.c_srates, uac2_opts->c_srates,
+			sizeof(agdev->params.c_srates));
 	agdev->params.c_ssize = uac2_opts->c_ssize;
 	if (FUOUT_EN(uac2_opts)) {
 		agdev->params.c_fu.id = USB_OUT_FU_ID;
@@ -1423,10 +1444,10 @@ in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	u8 entity_id = (w_index >> 8) & 0xff;
 	u8 control_selector = w_value >> 8;
 	int value = -EOPNOTSUPP;
-	int p_srate, c_srate;
+	u32 p_srate, c_srate;
 
-	p_srate = opts->p_srate;
-	c_srate = opts->c_srate;
+	u_audio_get_playback_srate(agdev, &p_srate);
+	u_audio_get_capture_srate(agdev, &c_srate);
 
 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
 		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
@@ -1500,28 +1521,39 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	u8 entity_id = (w_index >> 8) & 0xff;
 	u8 control_selector = w_value >> 8;
 	int value = -EOPNOTSUPP;
-	int p_srate, c_srate;
-
-	p_srate = opts->p_srate;
-	c_srate = opts->c_srate;
 
 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
 		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
-			struct cntrl_range_lay3 r;
+			struct cntrl_ranges_lay3_srates rs;
+			int i;
+			int wNumSubRanges = 0;
+			int srate;
+			int *srates;
 
 			if (entity_id == USB_IN_CLK_ID)
-				r.dMIN = cpu_to_le32(p_srate);
+				srates = opts->p_srates;
 			else if (entity_id == USB_OUT_CLK_ID)
-				r.dMIN = cpu_to_le32(c_srate);
+				srates = opts->c_srates;
 			else
 				return -EOPNOTSUPP;
-
-			r.dMAX = r.dMIN;
-			r.dRES = 0;
-			r.wNumSubRanges = cpu_to_le16(1);
-
-			value = min_t(unsigned int, w_length, sizeof(r));
-			memcpy(req->buf, &r, value);
+			for (i = 0; i < UAC_MAX_RATES; i++) {
+				srate = srates[i];
+				if (srate == 0)
+					break;
+
+				rs.r[wNumSubRanges].dMIN = cpu_to_le32(srate);
+				rs.r[wNumSubRanges].dMAX = cpu_to_le32(srate);
+				rs.r[wNumSubRanges].dRES = 0;
+				wNumSubRanges++;
+				dev_dbg(&agdev->gadget->dev,
+					"%s(): clk %d: rate ID %d: %d\n",
+					__func__, entity_id, wNumSubRanges, srate);
+			}
+			rs.wNumSubRanges = cpu_to_le16(wNumSubRanges);
+			value = min_t(unsigned int, w_length, ranges_lay3_size(rs));
+			dev_dbg(&agdev->gadget->dev, "%s(): sending %d rates, size %d\n",
+				__func__, rs.wNumSubRanges, value);
+			memcpy(req->buf, &rs, value);
 		} else {
 			dev_err(&agdev->gadget->dev,
 				"%s:%d control_selector=%d TODO!\n",
@@ -1580,6 +1612,25 @@ ac_rq_in(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 		return -EOPNOTSUPP;
 }
 
+static void uac2_cs_control_sam_freq(struct usb_ep *ep, struct usb_request *req)
+{
+	struct usb_function *fn = ep->driver_data;
+	struct g_audio *agdev = func_to_g_audio(fn);
+	struct f_uac2 *uac2 = func_to_uac2(fn);
+	u32 val;
+
+	if (req->actual != 4)
+		return;
+
+	val = le32_to_cpu(*((u32 *)req->buf));
+	dev_dbg(&agdev->gadget->dev, "%s val: %d.\n", __func__, val);
+	if (uac2->clock_id == USB_IN_CLK_ID) {
+		u_audio_set_playback_srate(agdev, val);
+	} else if (uac2->clock_id == USB_OUT_CLK_ID) {
+		u_audio_set_capture_srate(agdev, val);
+	}
+}
+
 static void
 out_rq_cur_complete(struct usb_ep *ep, struct usb_request *req)
 {
@@ -1631,6 +1682,7 @@ out_rq_cur_complete(struct usb_ep *ep, struct usb_request *req)
 static int
 out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
+	struct usb_composite_dev *cdev = fn->config->cdev;
 	struct usb_request *req = fn->config->cdev->req;
 	struct g_audio *agdev = func_to_g_audio(fn);
 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
@@ -1640,10 +1692,17 @@ out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	u16 w_value = le16_to_cpu(cr->wValue);
 	u8 entity_id = (w_index >> 8) & 0xff;
 	u8 control_selector = w_value >> 8;
+	u8 clock_id = w_index >> 8;
 
 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
-		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ)
+		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
+			dev_dbg(&agdev->gadget->dev,
+				"control_selector UAC2_CS_CONTROL_SAM_FREQ, clock: %d\n", clock_id);
+			cdev->gadget->ep0->driver_data = fn;
+			uac2->clock_id = clock_id;
+			req->complete = uac2_cs_control_sam_freq;
 			return w_length;
+		}
 	} else if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
 		memcpy(&uac2->setup_cr, cr, sizeof(*cr));
@@ -1836,11 +1895,70 @@ end:									\
 									\
 CONFIGFS_ATTR(f_uac2_opts_, name)
 
+#define UAC2_RATE_ATTRIBUTE(name)					\
+static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
+					 char *page)			\
+{									\
+	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
+	int result = 0;							\
+	int i;								\
+									\
+	mutex_lock(&opts->lock);					\
+	page[0] = '\0';							\
+	for (i = 0; i < UAC_MAX_RATES; i++) {				\
+		if (opts->name##s[i] == 0)				\
+			break;						\
+		result += sprintf(page + strlen(page), "%u,",		\
+				opts->name##s[i]);			\
+	}								\
+	if (strlen(page) > 0)						\
+		page[strlen(page) - 1] = '\n';				\
+	mutex_unlock(&opts->lock);					\
+									\
+	return result;							\
+}									\
+									\
+static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
+					  const char *page, size_t len)	\
+{									\
+	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
+	char *split_page = NULL;					\
+	int ret = -EINVAL;						\
+	char *token;							\
+	u32 num;							\
+	int i;								\
+									\
+	mutex_lock(&opts->lock);					\
+	if (opts->refcnt) {						\
+		ret = -EBUSY;						\
+		goto end;						\
+	}								\
+									\
+	i = 0;								\
+	memset(opts->name##s, 0x00, sizeof(opts->name##s));		\
+	split_page = kstrdup(page, GFP_KERNEL);				\
+	while ((token = strsep(&split_page, ",")) != NULL) {		\
+		ret = kstrtou32(token, 0, &num);			\
+		if (ret)						\
+			goto end;					\
+									\
+		opts->name##s[i++] = num;				\
+		ret = len;						\
+	};								\
+									\
+end:									\
+	kfree(split_page);						\
+	mutex_unlock(&opts->lock);					\
+	return ret;							\
+}									\
+									\
+CONFIGFS_ATTR(f_uac2_opts_, name)
+
 UAC2_ATTRIBUTE(u32, p_chmask);
-UAC2_ATTRIBUTE(u32, p_srate);
+UAC2_RATE_ATTRIBUTE(p_srate);
 UAC2_ATTRIBUTE(u32, p_ssize);
 UAC2_ATTRIBUTE(u32, c_chmask);
-UAC2_ATTRIBUTE(u32, c_srate);
+UAC2_RATE_ATTRIBUTE(c_srate);
 UAC2_ATTRIBUTE_SYNC(c_sync);
 UAC2_ATTRIBUTE(u32, c_ssize);
 UAC2_ATTRIBUTE(u32, req_number);
@@ -1913,10 +2031,10 @@ static struct usb_function_instance *afunc_alloc_inst(void)
 				    &f_uac2_func_type);
 
 	opts->p_chmask = UAC2_DEF_PCHMASK;
-	opts->p_srate = UAC2_DEF_PSRATE;
+	opts->p_srates[0] = UAC2_DEF_PSRATE;
 	opts->p_ssize = UAC2_DEF_PSSIZE;
 	opts->c_chmask = UAC2_DEF_CCHMASK;
-	opts->c_srate = UAC2_DEF_CSRATE;
+	opts->c_srates[0] = UAC2_DEF_CSRATE;
 	opts->c_ssize = UAC2_DEF_CSSIZE;
 	opts->c_sync = UAC2_DEF_CSYNC;
 
diff --git a/drivers/usb/gadget/function/u_uac2.h b/drivers/usb/gadget/function/u_uac2.h
index e0c8e3513bfd..6bfcf6d0e863 100644
--- a/drivers/usb/gadget/function/u_uac2.h
+++ b/drivers/usb/gadget/function/u_uac2.h
@@ -14,6 +14,7 @@
 #define U_UAC2_H
 
 #include <linux/usb/composite.h>
+#include "uac_common.h"
 
 #define UAC2_DEF_PCHMASK 0x3
 #define UAC2_DEF_PSRATE 48000
@@ -35,10 +36,10 @@
 struct f_uac2_opts {
 	struct usb_function_instance	func_inst;
 	int				p_chmask;
-	int				p_srate;
+	int				p_srates[UAC_MAX_RATES];
 	int				p_ssize;
 	int				c_chmask;
-	int				c_srate;
+	int				c_srates[UAC_MAX_RATES];
 	int				c_ssize;
 	int				c_sync;
 
diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index 5ec477ffab7f..d14b9f2d4c07 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -26,9 +26,10 @@ module_param(p_chmask, uint, 0444);
 MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");
 
 /* Playback Default 48 KHz */
-static int p_srate = UAC2_DEF_PSRATE;
-module_param(p_srate, uint, 0444);
-MODULE_PARM_DESC(p_srate, "Playback Sampling Rate");
+static int p_srates[UAC_MAX_RATES] = {UAC2_DEF_PSRATE};
+static int p_srates_cnt = 1;
+module_param_array_named(p_srate, p_srates, uint, &p_srates_cnt, 0444);
+MODULE_PARM_DESC(p_srate, "Playback Sampling Rates (array)");
 
 /* Playback Default 16bits/sample */
 static int p_ssize = UAC2_DEF_PSSIZE;
@@ -41,9 +42,10 @@ module_param(c_chmask, uint, 0444);
 MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");
 
 /* Capture Default 64 KHz */
-static int c_srate = UAC2_DEF_CSRATE;
-module_param(c_srate, uint, 0444);
-MODULE_PARM_DESC(c_srate, "Capture Sampling Rate");
+static int c_srates[UAC_MAX_RATES] = {UAC2_DEF_CSRATE};
+static int c_srates_cnt = 1;
+module_param_array_named(c_srate, c_srates, uint, &c_srates_cnt, 0444);
+MODULE_PARM_DESC(c_srate, "Capture Sampling Rates (array)");
 
 /* Capture Default 16bits/sample */
 static int c_ssize = UAC2_DEF_CSSIZE;
@@ -237,6 +239,7 @@ static int audio_bind(struct usb_composite_dev *cdev)
 {
 #ifndef CONFIG_GADGET_UAC1
 	struct f_uac2_opts	*uac2_opts;
+	int i;
 #else
 #ifndef CONFIG_GADGET_UAC1_LEGACY
 	struct f_uac1_opts	*uac1_opts;
@@ -263,10 +266,16 @@ static int audio_bind(struct usb_composite_dev *cdev)
 #ifndef CONFIG_GADGET_UAC1
 	uac2_opts = container_of(fi_uac2, struct f_uac2_opts, func_inst);
 	uac2_opts->p_chmask = p_chmask;
-	uac2_opts->p_srate = p_srate;
+
+	for (i = 0; i < p_srates_cnt; ++i)
+		uac2_opts->p_srates[i] = p_srates[i];
+
 	uac2_opts->p_ssize = p_ssize;
 	uac2_opts->c_chmask = c_chmask;
-	uac2_opts->c_srate = c_srate;
+
+	for (i = 0; i < c_srates_cnt; ++i)
+		uac2_opts->c_srates[i] = c_srates[i];
+
 	uac2_opts->c_ssize = c_ssize;
 	uac2_opts->req_number = UAC2_DEF_REQ_NUM;
 #else
-- 
2.25.1

[PATCH v4 06/10] usb: gadget: f_uac1: Support multiple sampling rates

[Pavel Hofman]

From: Julian Scheel <julian@jusst.de>

A list of sampling rates can be specified via configfs. All enabled
sampling rates are sent to the USB host on request. When the host
selects a sampling rate the internal active rate is updated.

Config strings with single value stay compatible with the previous version.

Multiple samplerates passed as configuration arrays to g_audio module
when built for f_uac1.

Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3:
* audio.c: fixed unused variables for CONFIG_UAC1 variants
* audio: used 0444 instead of S_IRUGO
* f_uac1: moved current state srates from struct f_uac1_opts to f_uac1
* f_uac1: renamed UAC_RATE1_ATTRIBUTE -> UAC1_RATE_ATTRIBUTE, moved from
  u_uac1.h to f_uac1.c
* updated commit message
---
 .../ABI/testing/configfs-usb-gadget-uac1      |   4 +-
 Documentation/usb/gadget-testing.rst          |   4 +-
 drivers/usb/gadget/function/f_uac1.c          | 181 +++++++++++++++---
 drivers/usb/gadget/function/u_uac1.h          |   5 +-
 drivers/usb/gadget/legacy/audio.c             |  25 ++-
 5 files changed, 179 insertions(+), 40 deletions(-)

diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac1 b/Documentation/ABI/testing/configfs-usb-gadget-uac1
index d4b8cf40a9e4..09725e273e9b 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uac1
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uac1
@@ -6,7 +6,7 @@ Description:
 
 		=====================	=======================================
 		c_chmask		capture channel mask
-		c_srate			capture sampling rate
+		c_srate			list of capture sampling rates (comma-separated)
 		c_ssize			capture sample size (bytes)
 		c_mute_present		capture mute control enable
 		c_volume_present	capture volume control enable
@@ -17,7 +17,7 @@ Description:
 		c_volume_res		capture volume control resolution
 					(in 1/256 dB)
 		p_chmask		playback channel mask
-		p_srate			playback sampling rate
+		p_srate			list of playback sampling rates (comma-separated)
 		p_ssize			playback sample size (bytes)
 		p_mute_present		playback mute control enable
 		p_volume_present	playback volume control enable
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
index 419f6e5e890a..046842b00c89 100644
--- a/Documentation/usb/gadget-testing.rst
+++ b/Documentation/usb/gadget-testing.rst
@@ -916,7 +916,7 @@ The uac1 function provides these attributes in its function directory:
 
 	================ ====================================================
 	c_chmask         capture channel mask
-	c_srate          capture sampling rate
+	c_srate          list of capture sampling rates (comma-separated)
 	c_ssize          capture sample size (bytes)
 	c_mute_present   capture mute control enable
 	c_volume_present capture volume control enable
@@ -924,7 +924,7 @@ The uac1 function provides these attributes in its function directory:
 	c_volume_max     capture volume control max value (in 1/256 dB)
 	c_volume_res     capture volume control resolution (in 1/256 dB)
 	p_chmask         playback channel mask
-	p_srate          playback sampling rate
+	p_srate          list of playback sampling rates (comma-separated)
 	p_ssize          playback sample size (bytes)
 	p_mute_present   playback mute control enable
 	p_volume_present playback volume control enable
diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 0397b27df42e..73df76a6fbe0 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -3,6 +3,7 @@
  * f_uac1.c -- USB Audio Class 1.0 Function (using u_audio API)
  *
  * Copyright (C) 2016 Ruslan Bilovol <ruslan.bilovol@gmail.com>
+ * Copyright (C) 2021 Julian Scheel <julian@jusst.de>
  *
  * This driver doesn't expect any real Audio codec to be present
  * on the device - the audio streams are simply sinked to and
@@ -42,6 +43,9 @@ struct f_uac1 {
 	/* Interrupt IN endpoint of AC interface */
 	struct usb_ep	*int_ep;
 	atomic_t	int_count;
+	int ctl_id;		/* EP id */
+	int c_srate;	/* current capture srate */
+	int p_srate;	/* current playback prate */
 };
 
 static inline struct f_uac1 *func_to_uac1(struct usb_function *f)
@@ -188,16 +192,18 @@ static struct uac1_as_header_descriptor as_in_header_desc = {
 	.wFormatTag =		cpu_to_le16(UAC_FORMAT_TYPE_I_PCM),
 };
 
-DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
+DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(UAC_MAX_RATES);
+#define uac_format_type_i_discrete_descriptor			\
+	uac_format_type_i_discrete_descriptor_##UAC_MAX_RATES
 
-static struct uac_format_type_i_discrete_descriptor_1 as_out_type_i_desc = {
-	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
+static struct uac_format_type_i_discrete_descriptor as_out_type_i_desc = {
+	.bLength =		0, /* filled on rate setup */
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
 	.bFormatType =		UAC_FORMAT_TYPE_I,
 	.bSubframeSize =	2,
 	.bBitResolution =	16,
-	.bSamFreqType =		1,
+	.bSamFreqType =		0, /* filled on rate setup */
 };
 
 /* Standard ISO OUT Endpoint Descriptor */
@@ -221,14 +227,14 @@ static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
 	.wLockDelay =		cpu_to_le16(1),
 };
 
-static struct uac_format_type_i_discrete_descriptor_1 as_in_type_i_desc = {
-	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
+static struct uac_format_type_i_discrete_descriptor as_in_type_i_desc = {
+	.bLength =		0, /* filled on rate setup */
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
 	.bFormatType =		UAC_FORMAT_TYPE_I,
 	.bSubframeSize =	2,
 	.bBitResolution =	16,
-	.bSamFreqType =		1,
+	.bSamFreqType =		0, /* filled on rate setup */
 };
 
 /* Standard ISO OUT Endpoint Descriptor */
@@ -333,6 +339,30 @@ static struct usb_gadget_strings *uac1_strings[] = {
  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
  */
 
+static void uac_cs_attr_sample_rate(struct usb_ep *ep, struct usb_request *req)
+{
+	struct usb_function *fn = ep->driver_data;
+	struct usb_composite_dev *cdev = fn->config->cdev;
+	struct g_audio *agdev = func_to_g_audio(fn);
+	struct f_uac1 *uac1 = func_to_uac1(fn);
+	u8 *buf = (u8 *)req->buf;
+	u32 val = 0;
+
+	if (req->actual != 3) {
+		WARN(cdev, "Invalid data size for UAC_EP_CS_ATTR_SAMPLE_RATE.\n");
+		return;
+	}
+
+	val = buf[0] | (buf[1] << 8) | (buf[2] << 16);
+	if (uac1->ctl_id == (USB_DIR_IN | 2)) {
+		uac1->p_srate = val;
+		u_audio_set_playback_srate(agdev, uac1->p_srate);
+	} else if (uac1->ctl_id == (USB_DIR_OUT | 1)) {
+		uac1->c_srate = val;
+		u_audio_set_capture_srate(agdev, uac1->c_srate);
+	}
+}
+
 static void audio_notify_complete(struct usb_ep *_ep, struct usb_request *req)
 {
 	struct g_audio *audio = req->context;
@@ -707,18 +737,27 @@ static int audio_set_endpoint_req(struct usb_function *f,
 		const struct usb_ctrlrequest *ctrl)
 {
 	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request	*req = f->config->cdev->req;
+	struct f_uac1		*uac1 = func_to_uac1(f);
 	int			value = -EOPNOTSUPP;
 	u16			ep = le16_to_cpu(ctrl->wIndex);
 	u16			len = le16_to_cpu(ctrl->wLength);
 	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u8			cs = w_value >> 8;
 
 	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 			ctrl->bRequest, w_value, len, ep);
 
 	switch (ctrl->bRequest) {
-	case UAC_SET_CUR:
+	case UAC_SET_CUR: {
+		if (cs == UAC_EP_CS_ATTR_SAMPLE_RATE) {
+			cdev->gadget->ep0->driver_data = f;
+			uac1->ctl_id = ep;
+			req->complete = uac_cs_attr_sample_rate;
+		}
 		value = len;
 		break;
+	}
 
 	case UAC_SET_MIN:
 		break;
@@ -743,16 +782,33 @@ static int audio_get_endpoint_req(struct usb_function *f,
 		const struct usb_ctrlrequest *ctrl)
 {
 	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request *req = f->config->cdev->req;
+	struct f_uac1 *uac1 = func_to_uac1(f);
+	u8 *buf = (u8 *)req->buf;
 	int value = -EOPNOTSUPP;
-	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
+	u8 ep = le16_to_cpu(ctrl->wIndex);
 	u16 len = le16_to_cpu(ctrl->wLength);
 	u16 w_value = le16_to_cpu(ctrl->wValue);
+	u8 cs = w_value >> 8;
+	u32 val = 0;
 
 	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 			ctrl->bRequest, w_value, len, ep);
 
 	switch (ctrl->bRequest) {
-	case UAC_GET_CUR:
+	case UAC_GET_CUR: {
+		if (cs == UAC_EP_CS_ATTR_SAMPLE_RATE) {
+			if (ep == (USB_DIR_IN | 2))
+				val = uac1->p_srate;
+			else if (ep == (USB_DIR_OUT | 1))
+				val = uac1->c_srate;
+			buf[2] = (val >> 16) & 0xff;
+			buf[1] = (val >> 8) & 0xff;
+			buf[0] = val & 0xff;
+		}
+		value = len;
+		break;
+	}
 	case UAC_GET_MIN:
 	case UAC_GET_MAX:
 	case UAC_GET_RES:
@@ -1074,10 +1130,10 @@ static int f_audio_validate_opts(struct g_audio *audio, struct device *dev)
 	} else if ((opts->c_ssize < 1) || (opts->c_ssize > 4)) {
 		dev_err(dev, "Error: incorrect capture sample size\n");
 		return -EINVAL;
-	} else if (!opts->p_srate) {
+	} else if (!opts->p_srates[0]) {
 		dev_err(dev, "Error: incorrect playback sampling rate\n");
 		return -EINVAL;
-	} else if (!opts->c_srate) {
+	} else if (!opts->c_srates[0]) {
 		dev_err(dev, "Error: incorrect capture sampling rate\n");
 		return -EINVAL;
 	}
@@ -1118,10 +1174,9 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	struct f_uac1_opts		*audio_opts;
 	struct usb_ep			*ep = NULL;
 	struct usb_string		*us;
-	u8				*sam_freq;
-	int				rate;
 	int				ba_iface_id;
 	int				status;
+	int				idx, i;
 
 	status = f_audio_validate_opts(audio, dev);
 	if (status)
@@ -1213,12 +1268,25 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	}
 
 	/* Set sample rates */
-	rate = audio_opts->c_srate;
-	sam_freq = as_out_type_i_desc.tSamFreq[0];
-	memcpy(sam_freq, &rate, 3);
-	rate = audio_opts->p_srate;
-	sam_freq = as_in_type_i_desc.tSamFreq[0];
-	memcpy(sam_freq, &rate, 3);
+	for (i = 0, idx = 0; i < UAC_MAX_RATES; i++) {
+		if (audio_opts->c_srates[i] == 0)
+			break;
+		memcpy(as_out_type_i_desc.tSamFreq[idx++],
+				&audio_opts->c_srates[i], 3);
+	}
+	as_out_type_i_desc.bLength = UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(idx);
+	as_out_type_i_desc.bSamFreqType = idx;
+
+	for (i = 0, idx = 0; i < UAC_MAX_RATES; i++) {
+		if (audio_opts->p_srates[i] == 0)
+			break;
+		memcpy(as_in_type_i_desc.tSamFreq[idx++],
+				&audio_opts->p_srates[i], 3);
+	}
+	as_in_type_i_desc.bLength = UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(idx);
+	as_in_type_i_desc.bSamFreqType = idx;
+	uac1->p_srate = audio_opts->p_srates[0];
+	uac1->c_srate = audio_opts->c_srates[0];
 
 	/* allocate instance-specific interface IDs, and patch descriptors */
 	status = usb_interface_id(c, f);
@@ -1297,7 +1365,8 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	audio->out_ep_maxpsize = le16_to_cpu(as_out_ep_desc.wMaxPacketSize);
 	audio->in_ep_maxpsize = le16_to_cpu(as_in_ep_desc.wMaxPacketSize);
 	audio->params.c_chmask = audio_opts->c_chmask;
-	audio->params.c_srates[0] = audio_opts->c_srate;
+	memcpy(audio->params.c_srates, audio_opts->c_srates,
+			sizeof(audio->params.c_srates));
 	audio->params.c_ssize = audio_opts->c_ssize;
 	if (FUIN_EN(audio_opts)) {
 		audio->params.p_fu.id = USB_IN_FU_ID;
@@ -1309,7 +1378,8 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 		audio->params.p_fu.volume_res = audio_opts->p_volume_res;
 	}
 	audio->params.p_chmask = audio_opts->p_chmask;
-	audio->params.p_srates[0] = audio_opts->p_srate;
+	memcpy(audio->params.p_srates, audio_opts->p_srates,
+			sizeof(audio->params.p_srates));
 	audio->params.p_ssize = audio_opts->p_ssize;
 	if (FUOUT_EN(audio_opts)) {
 		audio->params.c_fu.id = USB_OUT_FU_ID;
@@ -1414,11 +1484,70 @@ end:									\
 									\
 CONFIGFS_ATTR(f_uac1_opts_, name)
 
+#define UAC1_RATE_ATTRIBUTE(name)					\
+static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
+					 char *page)			\
+{									\
+	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
+	int result = 0;							\
+	int i;								\
+									\
+	mutex_lock(&opts->lock);					\
+	page[0] = '\0';							\
+	for (i = 0; i < UAC_MAX_RATES; i++) {				\
+		if (opts->name##s[i] == 0)				\
+			break;						\
+		result += sprintf(page + strlen(page), "%u,",		\
+				opts->name##s[i]);			\
+	}								\
+	if (strlen(page) > 0)						\
+		page[strlen(page) - 1] = '\n';				\
+	mutex_unlock(&opts->lock);					\
+									\
+	return result;							\
+}									\
+									\
+static ssize_t f_uac1_opts_##name##_store(struct config_item *item,	\
+					  const char *page, size_t len)	\
+{									\
+	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
+	char *split_page = NULL;					\
+	int ret = -EINVAL;						\
+	char *token;							\
+	u32 num;							\
+	int i;								\
+									\
+	mutex_lock(&opts->lock);					\
+	if (opts->refcnt) {						\
+		ret = -EBUSY;						\
+		goto end;						\
+	}								\
+									\
+	i = 0;								\
+	memset(opts->name##s, 0x00, sizeof(opts->name##s));		\
+	split_page = kstrdup(page, GFP_KERNEL);				\
+	while ((token = strsep(&split_page, ",")) != NULL) {		\
+		ret = kstrtou32(token, 0, &num);			\
+		if (ret)						\
+			goto end;					\
+									\
+		opts->name##s[i++] = num;				\
+		ret = len;						\
+	};								\
+									\
+end:									\
+	kfree(split_page);						\
+	mutex_unlock(&opts->lock);					\
+	return ret;							\
+}									\
+									\
+CONFIGFS_ATTR(f_uac1_opts_, name)
+
 UAC1_ATTRIBUTE(u32, c_chmask);
-UAC1_ATTRIBUTE(u32, c_srate);
+UAC1_RATE_ATTRIBUTE(c_srate);
 UAC1_ATTRIBUTE(u32, c_ssize);
 UAC1_ATTRIBUTE(u32, p_chmask);
-UAC1_ATTRIBUTE(u32, p_srate);
+UAC1_RATE_ATTRIBUTE(p_srate);
 UAC1_ATTRIBUTE(u32, p_ssize);
 UAC1_ATTRIBUTE(u32, req_number);
 
@@ -1487,10 +1616,10 @@ static struct usb_function_instance *f_audio_alloc_inst(void)
 				    &f_uac1_func_type);
 
 	opts->c_chmask = UAC1_DEF_CCHMASK;
-	opts->c_srate = UAC1_DEF_CSRATE;
+	opts->c_srates[0] = UAC1_DEF_CSRATE;
 	opts->c_ssize = UAC1_DEF_CSSIZE;
 	opts->p_chmask = UAC1_DEF_PCHMASK;
-	opts->p_srate = UAC1_DEF_PSRATE;
+	opts->p_srates[0] = UAC1_DEF_PSRATE;
 	opts->p_ssize = UAC1_DEF_PSSIZE;
 
 	opts->p_mute_present = UAC1_DEF_MUTE_PRESENT;
diff --git a/drivers/usb/gadget/function/u_uac1.h b/drivers/usb/gadget/function/u_uac1.h
index 589fae861141..b6cd6171d306 100644
--- a/drivers/usb/gadget/function/u_uac1.h
+++ b/drivers/usb/gadget/function/u_uac1.h
@@ -9,6 +9,7 @@
 #define __U_UAC1_H
 
 #include <linux/usb/composite.h>
+#include "uac_common.h"
 
 #define UAC1_OUT_EP_MAX_PACKET_SIZE	200
 #define UAC1_DEF_CCHMASK	0x3
@@ -30,10 +31,10 @@
 struct f_uac1_opts {
 	struct usb_function_instance	func_inst;
 	int				c_chmask;
-	int				c_srate;
+	int				c_srates[UAC_MAX_RATES];
 	int				c_ssize;
 	int				p_chmask;
-	int				p_srate;
+	int				p_srates[UAC_MAX_RATES];
 	int				p_ssize;
 
 	bool			p_mute_present;
diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index d14b9f2d4c07..c89c777a1aa3 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -61,9 +61,10 @@ module_param(p_chmask, uint, 0444);
 MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");
 
 /* Playback Default 48 KHz */
-static int p_srate = UAC1_DEF_PSRATE;
-module_param(p_srate, uint, 0444);
-MODULE_PARM_DESC(p_srate, "Playback Sampling Rate");
+static int p_srates[UAC_MAX_RATES] = {UAC1_DEF_PSRATE};
+static int p_srates_cnt = 1;
+module_param_array_named(p_srate, p_srates, uint, &p_srates_cnt, 0444);
+MODULE_PARM_DESC(p_srate, "Playback Sampling Rates (array)");
 
 /* Playback Default 16bits/sample */
 static int p_ssize = UAC1_DEF_PSSIZE;
@@ -76,9 +77,10 @@ module_param(c_chmask, uint, 0444);
 MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");
 
 /* Capture Default 48 KHz */
-static int c_srate = UAC1_DEF_CSRATE;
-module_param(c_srate, uint, 0444);
-MODULE_PARM_DESC(c_srate, "Capture Sampling Rate");
+static int c_srates[UAC_MAX_RATES] = {UAC1_DEF_CSRATE};
+static int c_srates_cnt = 1;
+module_param_array_named(c_srate, c_srates, uint, &c_srates_cnt, 0444);
+MODULE_PARM_DESC(c_srate, "Capture Sampling Rates (array)");
 
 /* Capture Default 16bits/sample */
 static int c_ssize = UAC1_DEF_CSSIZE;
@@ -243,6 +245,7 @@ static int audio_bind(struct usb_composite_dev *cdev)
 #else
 #ifndef CONFIG_GADGET_UAC1_LEGACY
 	struct f_uac1_opts	*uac1_opts;
+	int i;
 #else
 	struct f_uac1_legacy_opts	*uac1_opts;
 #endif
@@ -282,10 +285,16 @@ static int audio_bind(struct usb_composite_dev *cdev)
 #ifndef CONFIG_GADGET_UAC1_LEGACY
 	uac1_opts = container_of(fi_uac1, struct f_uac1_opts, func_inst);
 	uac1_opts->p_chmask = p_chmask;
-	uac1_opts->p_srate = p_srate;
+
+	for (i = 0; i < p_srates_cnt; ++i)
+		uac1_opts->p_srates[i] = p_srates[i];
+
 	uac1_opts->p_ssize = p_ssize;
 	uac1_opts->c_chmask = c_chmask;
-	uac1_opts->c_srate = c_srate;
+
+	for (i = 0; i < c_srates_cnt; ++i)
+		uac1_opts->c_srates[i] = c_srates[i];
+
 	uac1_opts->c_ssize = c_ssize;
 	uac1_opts->req_number = UAC1_DEF_REQ_NUM;
 #else /* CONFIG_GADGET_UAC1_LEGACY */
-- 
2.25.1

[PATCH v4 07/10] usb: gadget: u_audio: Rate ctl notifies about current srate (0=stopped)

[Pavel Hofman]

The Playback/Capture ctl currently reports rate value set by USB
control selector UAC2_CS_CONTROL_SAM_FREQ (fixed for UAC1). When the
stops playback/capture, the reported value does not change.  The gadget
side has no information whether the host has started/stopped
capture/playback.

This patch sets the value reported by the respective rate ctl to zero
when the host side has stopped playback/capture. Also, it calls
snd_ctl_notify when start/stop  occurs, so that a subscribed client can
act appropriately.

Tests have confirmed that USB hosts change UAC2_CS_CONTROL_SAM_FREQ
before switching altsetting to activate playback/capture, resulting in
correct order (params->c/p_srate is set to requested rate before
u_audio_start_capture/playback is called).

The gadget rate notifications are used by user-space audio gadget
controller gaudio_ctl https://github.com/pavhofman/gaudio_ctl.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3:
* using prm->srate instead of params->c_srate/p_srate due to the added commit
  "[v3] usb: gadget: u_audio: Move dynamic srate from params to rtd"
---
 drivers/usb/gadget/function/u_audio.c | 28 ++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index 283a449a9538..fab1bc439002 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -65,6 +65,7 @@ struct uac_rtd_params {
 
 	struct snd_kcontrol *snd_kctl_rate; /* read-only current rate */
 	int srate; /* selected samplerate */
+	int active; /* playback/capture running */
 
   spinlock_t lock; /* lock for control transfers */
 
@@ -490,6 +491,21 @@ static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
 		dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
 }
 
+static void set_active(struct uac_rtd_params *prm, bool active)
+{
+	// notifying through the Rate ctrl
+	struct snd_kcontrol *kctl = prm->snd_kctl_rate;
+	unsigned long flags;
+
+	spin_lock_irqsave(&prm->lock, flags);
+	if (prm->active != active) {
+		prm->active = active;
+		snd_ctl_notify(prm->uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
+				&kctl->id);
+	}
+	spin_unlock_irqrestore(&prm->lock, flags);
+}
+
 int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
 {
 	struct uac_params *params = &audio_dev->params;
@@ -607,6 +623,8 @@ int u_audio_start_capture(struct g_audio *audio_dev)
 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 	}
 
+	set_active(&uac->c_prm, true);
+
 	ep_fback = audio_dev->in_ep_fback;
 	if (!ep_fback)
 		return 0;
@@ -652,6 +670,7 @@ void u_audio_stop_capture(struct g_audio *audio_dev)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
 
+	set_active(&uac->c_prm, false);
 	if (audio_dev->in_ep_fback)
 		free_ep_fback(&uac->c_prm, audio_dev->in_ep_fback);
 	free_ep(&uac->c_prm, audio_dev->out_ep);
@@ -723,6 +742,8 @@ int u_audio_start_playback(struct g_audio *audio_dev)
 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 	}
 
+	set_active(&uac->p_prm, true);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(u_audio_start_playback);
@@ -731,6 +752,7 @@ void u_audio_stop_playback(struct g_audio *audio_dev)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
 
+	set_active(&uac->p_prm, false);
 	free_ep(&uac->p_prm, audio_dev->in_ep);
 }
 EXPORT_SYMBOL_GPL(u_audio_stop_playback);
@@ -1074,7 +1096,11 @@ static int u_audio_rate_get(struct snd_kcontrol *kcontrol,
 	unsigned long flags;
 
 	spin_lock_irqsave(&prm->lock, flags);
-	ucontrol->value.integer.value[0] = prm->srate;
+	if (prm->active)
+		ucontrol->value.integer.value[0] = prm->srate;
+	else
+		/* not active: reporting zero rate */
+		ucontrol->value.integer.value[0] = 0;
 	spin_unlock_irqrestore(&prm->lock, flags);
 	return 0;
 }
-- 
2.25.1

[PATCH v4 08/10] usb: gadget: u_audio: Add suspend call

[Pavel Hofman]

Add exported method u_audio_suspend which sets stream status to
inactive and sends notifications. The method does not free any
resources.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3:
* fixed commit title
* removed stopping substreams (moved to a separate patch series)
* calling set_active(false) instead of the removed set_srate(0)
* updated commit msg
---
 drivers/usb/gadget/function/u_audio.c | 9 +++++++++
 drivers/usb/gadget/function/u_audio.h | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index fab1bc439002..2bb569895a90 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -757,6 +757,15 @@ void u_audio_stop_playback(struct g_audio *audio_dev)
 }
 EXPORT_SYMBOL_GPL(u_audio_stop_playback);
 
+void u_audio_suspend(struct g_audio *audio_dev)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+
+	set_active(&uac->p_prm, false);
+	set_active(&uac->c_prm, false);
+}
+EXPORT_SYMBOL_GPL(u_audio_suspend);
+
 int u_audio_get_volume(struct g_audio *audio_dev, int playback, s16 *val)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
index 5e6ed0f31cc3..9512b8fccfaa 100644
--- a/drivers/usb/gadget/function/u_audio.h
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -130,4 +130,6 @@ int u_audio_set_volume(struct g_audio *g_audio, int playback, s16 val);
 int u_audio_get_mute(struct g_audio *g_audio, int playback, int *val);
 int u_audio_set_mute(struct g_audio *g_audio, int playback, int val);
 
+void u_audio_suspend(struct g_audio *g_audio);
+
 #endif /* __U_AUDIO_H */
-- 
2.25.1

[PATCH v4 09/10] usb: gadget: f_uac2: Add suspend callback

[Pavel Hofman]

When USB cable gets disconnected, the undergoing playback/capture
stalls, without any notification to u_audio about the change.
Experiments with a dwc2 gadget revealed that Suspend interrupt is
thrown at cable disconnection, which the gadget framework translates to
calling suspend callback of a function, if it is defined.

Add the suspend callback to f_uac2 function, calling
corresponding method of u_audio in order to stop the respective PCM
streams and to notify subscribed clients at cable disconnection.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3: fixed commit title and msg
---
 drivers/usb/gadget/function/f_uac2.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 058a6a0b5444..6be60529cb25 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1432,6 +1432,14 @@ afunc_disable(struct usb_function *fn)
 		usb_ep_disable(uac2->int_ep);
 }
 
+static void
+afunc_suspend(struct usb_function *fn)
+{
+	struct f_uac2 *uac2 = func_to_uac2(fn);
+
+	u_audio_suspend(&uac2->g_audio);
+}
+
 static int
 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
@@ -2103,6 +2111,7 @@ static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
 	uac2->g_audio.func.set_alt = afunc_set_alt;
 	uac2->g_audio.func.get_alt = afunc_get_alt;
 	uac2->g_audio.func.disable = afunc_disable;
+	uac2->g_audio.func.suspend = afunc_suspend;
 	uac2->g_audio.func.setup = afunc_setup;
 	uac2->g_audio.func.free_func = afunc_free;
 
-- 
2.25.1

[PATCH v4 10/10] usb: gadget: f_uac1: Add suspend callback

[Pavel Hofman]

Add suspend callback to f_uac1 function, calling corresponding method
of u_audio in order to stop the respective PCM streams and to notify
subscribed clients about the stop.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
v3: fixed commit title and msg
---
 drivers/usb/gadget/function/f_uac1.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 73df76a6fbe0..1484e5c231d3 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -961,6 +961,14 @@ static void f_audio_disable(struct usb_function *f)
 		usb_ep_disable(uac1->int_ep);
 }
 
+static void
+f_audio_suspend(struct usb_function *f)
+{
+	struct f_uac1 *uac1 = func_to_uac1(f);
+
+	u_audio_suspend(&uac1->g_audio);
+}
+
 /*-------------------------------------------------------------------------*/
 static struct uac_feature_unit_descriptor *build_fu_desc(int chmask)
 {
@@ -1691,6 +1699,7 @@ static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 	uac1->g_audio.func.get_alt = f_audio_get_alt;
 	uac1->g_audio.func.setup = f_audio_setup;
 	uac1->g_audio.func.disable = f_audio_disable;
+	uac1->g_audio.func.suspend = f_audio_suspend;
 	uac1->g_audio.func.free_func = f_audio_free;
 
 	return &uac1->g_audio.func;
-- 
2.25.1

Re: [PATCH v4 05/10] usb: gadget: f_uac2: Support multiple sampling rates

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 5946 bytes --]

Hi Pavel,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on usb/usb-testing]
[also build test WARNING on next-20220112]
[cannot apply to linus/master balbi-usb/testing/next peter-chen-usb/for-usb-next v5.16]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Pavel-Hofman/usb-gadget-audio-Multiple-rates-notify/20220110-154453
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: i386-randconfig-s001 (https://download.01.org/0day-ci/archive/20220112/202201122317.eiQOLXzP-lkp(a)intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-dirty
        # https://github.com/0day-ci/linux/commit/275344f5925d7804375e3572fd2fbd1febb029a6
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Pavel-Hofman/usb-gadget-audio-Multiple-rates-notify/20220110-154453
        git checkout 275344f5925d7804375e3572fd2fbd1febb029a6
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash drivers/usb/gadget/function/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
>> drivers/usb/gadget/function/f_uac2.c:1553:33: sparse: sparse: restricted __le16 degrades to integer
   drivers/usb/gadget/function/f_uac2.c:1625:15: sparse: sparse: cast to restricted __le32

vim +1553 drivers/usb/gadget/function/f_uac2.c

  1511	
  1512	static int
  1513	in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
  1514	{
  1515		struct usb_request *req = fn->config->cdev->req;
  1516		struct g_audio *agdev = func_to_g_audio(fn);
  1517		struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
  1518		u16 w_length = le16_to_cpu(cr->wLength);
  1519		u16 w_index = le16_to_cpu(cr->wIndex);
  1520		u16 w_value = le16_to_cpu(cr->wValue);
  1521		u8 entity_id = (w_index >> 8) & 0xff;
  1522		u8 control_selector = w_value >> 8;
  1523		int value = -EOPNOTSUPP;
  1524	
  1525		if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
  1526			if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
  1527				struct cntrl_ranges_lay3_srates rs;
  1528				int i;
  1529				int wNumSubRanges = 0;
  1530				int srate;
  1531				int *srates;
  1532	
  1533				if (entity_id == USB_IN_CLK_ID)
  1534					srates = opts->p_srates;
  1535				else if (entity_id == USB_OUT_CLK_ID)
  1536					srates = opts->c_srates;
  1537				else
  1538					return -EOPNOTSUPP;
  1539				for (i = 0; i < UAC_MAX_RATES; i++) {
  1540					srate = srates[i];
  1541					if (srate == 0)
  1542						break;
  1543	
  1544					rs.r[wNumSubRanges].dMIN = cpu_to_le32(srate);
  1545					rs.r[wNumSubRanges].dMAX = cpu_to_le32(srate);
  1546					rs.r[wNumSubRanges].dRES = 0;
  1547					wNumSubRanges++;
  1548					dev_dbg(&agdev->gadget->dev,
  1549						"%s(): clk %d: rate ID %d: %d\n",
  1550						__func__, entity_id, wNumSubRanges, srate);
  1551				}
  1552				rs.wNumSubRanges = cpu_to_le16(wNumSubRanges);
> 1553				value = min_t(unsigned int, w_length, ranges_lay3_size(rs));
  1554				dev_dbg(&agdev->gadget->dev, "%s(): sending %d rates, size %d\n",
  1555					__func__, rs.wNumSubRanges, value);
  1556				memcpy(req->buf, &rs, value);
  1557			} else {
  1558				dev_err(&agdev->gadget->dev,
  1559					"%s:%d control_selector=%d TODO!\n",
  1560					__func__, __LINE__, control_selector);
  1561			}
  1562		} else if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
  1563				(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
  1564			unsigned int is_playback = 0;
  1565	
  1566			if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
  1567				is_playback = 1;
  1568	
  1569			if (control_selector == UAC_FU_VOLUME) {
  1570				struct cntrl_range_lay2 r;
  1571				s16 max_db, min_db, res_db;
  1572	
  1573				if (is_playback) {
  1574					max_db = opts->p_volume_max;
  1575					min_db = opts->p_volume_min;
  1576					res_db = opts->p_volume_res;
  1577				} else {
  1578					max_db = opts->c_volume_max;
  1579					min_db = opts->c_volume_min;
  1580					res_db = opts->c_volume_res;
  1581				}
  1582	
  1583				r.wMAX = cpu_to_le16(max_db);
  1584				r.wMIN = cpu_to_le16(min_db);
  1585				r.wRES = cpu_to_le16(res_db);
  1586				r.wNumSubRanges = cpu_to_le16(1);
  1587	
  1588				value = min_t(unsigned int, w_length, sizeof(r));
  1589				memcpy(req->buf, &r, value);
  1590			} else {
  1591				dev_err(&agdev->gadget->dev,
  1592					"%s:%d control_selector=%d TODO!\n",
  1593					__func__, __LINE__, control_selector);
  1594			}
  1595		} else {
  1596			dev_err(&agdev->gadget->dev,
  1597				"%s:%d entity_id=%d control_selector=%d TODO!\n",
  1598				__func__, __LINE__, entity_id, control_selector);
  1599		}
  1600	
  1601		return value;
  1602	}
  1603	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org