[PATCH 0/4] Add configfs HS/SS bInterval, optimized or fixed

[PATCH 0/4] Add configfs HS/SS bInterval, optimized or fixed

[Pavel Hofman]

The existing UAC2 gadget has hard-coded bInterval=4 for HS/SS EP IN and
EP OUT. This setting precludes using higher-bandwidth configurations
successfully (the srate/chmask/ssize combination is accepted, but data
are silently dropped). 

After discussing with John Keeping
(https://lore.kernel.org/all/YcHIsR4AFaL9g6N2@donbot/) this series
implements a compromise among the various requirements. Configfs params
c_hs_bint/p_hs_bint between 1 to 4 set fixed bInterval. If the params
are set to 0, maximum fitting max packet size and bInterval values for
the required bandwidth are calculated and used, minimizing thus CPU
load.

The default value is 0, i.e. the automated calculation. It was chosen to
simplify using the UAC2 gadget. Also, when existing installations
require minimum bInterval to achieve minimum latency, they had to be
modified in the code so far. Therefore it is assumed that having to set
the parameters to fixed bInterval values would be no major difference to
the current status.

Additionally, the code warns if the required bandwidth exceeds the used
max packet size/bInterval combination. The warning check if performed
for FS too even if the current configuration ends up using HS/SS. The
optimal solution would be preventing FS/HS/SS enumeration instead but
such feature will require more patches and is not part of this series.

The bInterval parameters are added to the legacy g_audio too as this
module is still used in many existing UAC2 gadget tutorials and the
added code is minimal.


With regards,

Pavel Hofman.

Pavel Hofman (4):
  usb: gadget: f_uac2: add HS/SS bInterval to configfs
  usb: gadget: audio: Add HS/SS bInterval params for UAC2
  usb: gadget: f_uac2: Optionally determine bInterval for HS and SS
  usb: gadget: f_uac2: Add speed names to bInterval dbg/warn

 .../ABI/testing/configfs-usb-gadget-uac2      |   2 +
 Documentation/usb/gadget-testing.rst          |   2 +
 drivers/usb/gadget/function/f_uac2.c          | 160 +++++++++++++-----
 drivers/usb/gadget/function/u_uac2.h          |   4 +
 drivers/usb/gadget/legacy/audio.c             |  15 ++
 5 files changed, 142 insertions(+), 41 deletions(-)

-- 
2.25.1

[PATCH 1/4] usb: gadget: f_uac2: Add HS/SS bInterval to configfs

[Pavel Hofman]

Allow configuring the HS/SS bInterval through configfs, via
parameters p_hs_bint/c_hs_bint separately for playback/capture.

The default param values are left at the original 4.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Suggested-by: John Keeping <john@metanate.com>
---
 .../ABI/testing/configfs-usb-gadget-uac2      |  2 ++
 Documentation/usb/gadget-testing.rst          |  2 ++
 drivers/usb/gadget/function/f_uac2.c          | 31 ++++++++++++++++---
 drivers/usb/gadget/function/u_uac2.h          |  4 +++
 4 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac2 b/Documentation/ABI/testing/configfs-usb-gadget-uac2
index 4c6bf63fcb22..33fb237b3ca5 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uac2
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uac2
@@ -8,6 +8,7 @@ Description:
 		c_chmask		capture channel mask
 		c_srate			list of capture sampling rates (comma-separated)
 		c_ssize			capture sample size (bytes)
+		c_hs_bint		capture bInterval for HS/SS (1-4)
 		c_sync			capture synchronization type
 					(async/adaptive)
 		c_mute_present		capture mute control enable
@@ -22,6 +23,7 @@ Description:
 		p_chmask		playback channel mask
 		p_srate			list of playback sampling rates (comma-separated)
 		p_ssize			playback sample size (bytes)
+		p_hs_bint		playback bInterval for HS/SS (1-4)
 		p_mute_present		playback mute control enable
 		p_volume_present	playback volume control enable
 		p_volume_min		playback volume control min value
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
index 6e8fdfaf19e7..bd91191683be 100644
--- a/Documentation/usb/gadget-testing.rst
+++ b/Documentation/usb/gadget-testing.rst
@@ -734,6 +734,7 @@ The uac2 function provides these attributes in its function directory:
 	c_volume_min     capture volume control min value (in 1/256 dB)
 	c_volume_max     capture volume control max value (in 1/256 dB)
 	c_volume_res     capture volume control resolution (in 1/256 dB)
+	c_hs_bint        capture bInterval for HS/SS (1-4)
 	fb_max           maximum extra bandwidth in async mode
 	p_chmask         playback channel mask
 	p_srate          list of playback sampling rates (comma-separated)
@@ -743,6 +744,7 @@ The uac2 function provides these attributes in its function directory:
 	p_volume_min     playback volume control min value (in 1/256 dB)
 	p_volume_max     playback volume control max value (in 1/256 dB)
 	p_volume_res     playback volume control resolution (in 1/256 dB)
+	p_hs_bint        playback bInterval for HS/SS (1-4)
 	req_number       the number of pre-allocated request for both capture
 	                 and playback
 	function_name    name of the interface
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index d874e0d34188..34bb6c9a9023 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -343,7 +343,7 @@ static struct usb_endpoint_descriptor hs_epout_desc = {
 
 	/* .bmAttributes = DYNAMIC */
 	/* .wMaxPacketSize = DYNAMIC */
-	.bInterval = 4,
+	/* .bInterval = DYNAMIC */
 };
 
 static struct usb_endpoint_descriptor ss_epout_desc = {
@@ -353,7 +353,7 @@ static struct usb_endpoint_descriptor ss_epout_desc = {
 	.bEndpointAddress = USB_DIR_OUT,
 	/* .bmAttributes = DYNAMIC */
 	/* .wMaxPacketSize = DYNAMIC */
-	.bInterval = 4,
+	/* .bInterval = DYNAMIC */
 };
 
 static struct usb_ss_ep_comp_descriptor ss_epout_desc_comp = {
@@ -477,7 +477,7 @@ static struct usb_endpoint_descriptor hs_epin_desc = {
 
 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 	/* .wMaxPacketSize = DYNAMIC */
-	.bInterval = 4,
+	/* .bInterval = DYNAMIC */
 };
 
 static struct usb_endpoint_descriptor ss_epin_desc = {
@@ -487,7 +487,7 @@ static struct usb_endpoint_descriptor ss_epin_desc = {
 	.bEndpointAddress = USB_DIR_IN,
 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 	/* .wMaxPacketSize = DYNAMIC */
-	.bInterval = 4,
+	/* .bInterval = DYNAMIC */
 };
 
 static struct usb_ss_ep_comp_descriptor ss_epin_desc_comp = {
@@ -965,6 +965,16 @@ static int afunc_validate_opts(struct g_audio *agdev, struct device *dev)
 			return -EINVAL;
 	}
 
+	if ((opts->p_hs_bint < 1) || (opts->p_hs_bint > 4)) {
+		dev_err(dev, "Error: incorrect playback HS/SS bInterval (1-4)\n");
+		return -EINVAL;
+	}
+
+	if ((opts->c_hs_bint < 1) || (opts->c_hs_bint > 4)) {
+		dev_err(dev, "Error: incorrect capture HS/SS bInterval (1-4)\n");
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -1125,6 +1135,11 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		std_ac_if_desc.bNumEndpoints = 1;
 	}
 
+	hs_epin_desc.bInterval = uac2_opts->p_hs_bint;
+	ss_epin_desc.bInterval = uac2_opts->p_hs_bint;
+	hs_epout_desc.bInterval = uac2_opts->c_hs_bint;
+	ss_epout_desc.bInterval = uac2_opts->c_hs_bint;
+
 	/* Calculate wMaxPacketSize according to audio bandwidth */
 	ret = set_ep_max_packet_size(uac2_opts, &fs_epin_desc, USB_SPEED_FULL,
 				     true);
@@ -1801,10 +1816,12 @@ static struct configfs_item_operations f_uac2_item_ops = {
 	.release	= f_uac2_attr_release,
 };
 
+#define uac2_kstrtou8 kstrtou8
 #define uac2_kstrtou32 kstrtou32
 #define uac2_kstrtos16 kstrtos16
 #define uac2_kstrtobool(s, base, res) kstrtobool((s), (res))
 
+static const char *u8_fmt = "%u\n";
 static const char *u32_fmt = "%u\n";
 static const char *s16_fmt = "%hd\n";
 static const char *bool_fmt = "%u\n";
@@ -2004,10 +2021,12 @@ CONFIGFS_ATTR(f_uac2_opts_, name)
 UAC2_ATTRIBUTE(u32, p_chmask);
 UAC2_RATE_ATTRIBUTE(p_srate);
 UAC2_ATTRIBUTE(u32, p_ssize);
+UAC2_ATTRIBUTE(u8, p_hs_bint);
 UAC2_ATTRIBUTE(u32, c_chmask);
 UAC2_RATE_ATTRIBUTE(c_srate);
 UAC2_ATTRIBUTE_SYNC(c_sync);
 UAC2_ATTRIBUTE(u32, c_ssize);
+UAC2_ATTRIBUTE(u8, c_hs_bint);
 UAC2_ATTRIBUTE(u32, req_number);
 
 UAC2_ATTRIBUTE(bool, p_mute_present);
@@ -2028,9 +2047,11 @@ static struct configfs_attribute *f_uac2_attrs[] = {
 	&f_uac2_opts_attr_p_chmask,
 	&f_uac2_opts_attr_p_srate,
 	&f_uac2_opts_attr_p_ssize,
+	&f_uac2_opts_attr_p_hs_bint,
 	&f_uac2_opts_attr_c_chmask,
 	&f_uac2_opts_attr_c_srate,
 	&f_uac2_opts_attr_c_ssize,
+	&f_uac2_opts_attr_c_hs_bint,
 	&f_uac2_opts_attr_c_sync,
 	&f_uac2_opts_attr_req_number,
 	&f_uac2_opts_attr_fb_max,
@@ -2083,9 +2104,11 @@ static struct usb_function_instance *afunc_alloc_inst(void)
 	opts->p_chmask = UAC2_DEF_PCHMASK;
 	opts->p_srates[0] = UAC2_DEF_PSRATE;
 	opts->p_ssize = UAC2_DEF_PSSIZE;
+	opts->p_hs_bint = UAC2_DEF_PHSBINT;
 	opts->c_chmask = UAC2_DEF_CCHMASK;
 	opts->c_srates[0] = UAC2_DEF_CSRATE;
 	opts->c_ssize = UAC2_DEF_CSSIZE;
+	opts->c_hs_bint = UAC2_DEF_CHSBINT;
 	opts->c_sync = UAC2_DEF_CSYNC;
 
 	opts->p_mute_present = UAC2_DEF_MUTE_PRESENT;
diff --git a/drivers/usb/gadget/function/u_uac2.h b/drivers/usb/gadget/function/u_uac2.h
index ed96c7c853e4..733a0e0945fb 100644
--- a/drivers/usb/gadget/function/u_uac2.h
+++ b/drivers/usb/gadget/function/u_uac2.h
@@ -19,9 +19,11 @@
 #define UAC2_DEF_PCHMASK 0x3
 #define UAC2_DEF_PSRATE 48000
 #define UAC2_DEF_PSSIZE 2
+#define UAC2_DEF_PHSBINT 4
 #define UAC2_DEF_CCHMASK 0x3
 #define UAC2_DEF_CSRATE 64000
 #define UAC2_DEF_CSSIZE 2
+#define UAC2_DEF_CHSBINT 4
 #define UAC2_DEF_CSYNC		USB_ENDPOINT_SYNC_ASYNC
 
 #define UAC2_DEF_MUTE_PRESENT	1
@@ -38,10 +40,12 @@ struct f_uac2_opts {
 	int				p_chmask;
 	int				p_srates[UAC_MAX_RATES];
 	int				p_ssize;
+	u8				p_hs_bint;
 	int				c_chmask;
 	int				c_srates[UAC_MAX_RATES];
 	int				c_ssize;
 	int				c_sync;
+	u8				c_hs_bint;
 
 	bool			p_mute_present;
 	bool			p_volume_present;
-- 
2.25.1

[PATCH 2/4] usb: gadget: audio: Add HS/SS bInterval params for UAC2

[Pavel Hofman]

Allow configuring the existing f_uac2 configfs bInterval params through
parameters of the gaudio module.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
 drivers/usb/gadget/legacy/audio.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index c89c777a1aa3..76ea6decf7b6 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -36,6 +36,12 @@ static int p_ssize = UAC2_DEF_PSSIZE;
 module_param(p_ssize, uint, 0444);
 MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");
 
+/* Playback bInterval for HS/SS (1-4: fixed, 0: auto) */
+static u8 p_hs_bint = UAC2_DEF_PHSBINT;
+module_param(p_hs_bint, byte, 0444);
+MODULE_PARM_DESC(p_hs_bint,
+		"Playback bInterval for HS/SS (1-4: fixed, 0: auto)");
+
 /* Capture(USB-OUT) Default Stereo - Fl/Fr */
 static int c_chmask = UAC2_DEF_CCHMASK;
 module_param(c_chmask, uint, 0444);
@@ -51,6 +57,13 @@ MODULE_PARM_DESC(c_srate, "Capture Sampling Rates (array)");
 static int c_ssize = UAC2_DEF_CSSIZE;
 module_param(c_ssize, uint, 0444);
 MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
+
+/* capture bInterval for HS/SS (1-4: fixed, 0: auto) */
+static u8 c_hs_bint = UAC2_DEF_CHSBINT;
+module_param(c_hs_bint, byte, 0444);
+MODULE_PARM_DESC(c_hs_bint,
+		"Capture bInterval for HS/SS (1-4: fixed, 0: auto)");
+
 #else
 #ifndef CONFIG_GADGET_UAC1_LEGACY
 #include "u_uac1.h"
@@ -274,12 +287,14 @@ static int audio_bind(struct usb_composite_dev *cdev)
 		uac2_opts->p_srates[i] = p_srates[i];
 
 	uac2_opts->p_ssize = p_ssize;
+	uac2_opts->p_hs_bint = p_hs_bint;
 	uac2_opts->c_chmask = c_chmask;
 
 	for (i = 0; i < c_srates_cnt; ++i)
 		uac2_opts->c_srates[i] = c_srates[i];
 
 	uac2_opts->c_ssize = c_ssize;
+	uac2_opts->c_hs_bint = c_hs_bint;
 	uac2_opts->req_number = UAC2_DEF_REQ_NUM;
 #else
 #ifndef CONFIG_GADGET_UAC1_LEGACY
-- 
2.25.1

[PATCH 3/4] usb: gadget: f_uac2: Optionally determine bInterval for HS and SS

[Pavel Hofman]

Allow setting configfs params p_hs_bint/c_hs_bint to 0. If they are set
to 0, determine the largest bInterval (4 to 1) for which the required
bandwidth of the max samplerate fits the max allowed packet size. If the
required bandwidth exceeds max bandwidth for single-packet mode
(ep->mc=1), keep bInterval at 1.

The FS speed is left at fixed bInterval=1.

If for any speed the required bandwidth exceeds the max bandwidth
corresponding to the selected/determined bInterval, print a warning.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
 .../ABI/testing/configfs-usb-gadget-uac2      |   4 +-
 Documentation/usb/gadget-testing.rst          |   4 +-
 drivers/usb/gadget/function/f_uac2.c          | 126 ++++++++++++------
 drivers/usb/gadget/function/u_uac2.h          |   4 +-
 4 files changed, 91 insertions(+), 47 deletions(-)

diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac2 b/Documentation/ABI/testing/configfs-usb-gadget-uac2
index 33fb237b3ca5..3371c39f651d 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uac2
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uac2
@@ -8,7 +8,7 @@ Description:
 		c_chmask		capture channel mask
 		c_srate			list of capture sampling rates (comma-separated)
 		c_ssize			capture sample size (bytes)
-		c_hs_bint		capture bInterval for HS/SS (1-4)
+		c_hs_bint		capture bInterval for HS/SS (1-4: fixed, 0: auto)
 		c_sync			capture synchronization type
 					(async/adaptive)
 		c_mute_present		capture mute control enable
@@ -23,7 +23,7 @@ Description:
 		p_chmask		playback channel mask
 		p_srate			list of playback sampling rates (comma-separated)
 		p_ssize			playback sample size (bytes)
-		p_hs_bint		playback bInterval for HS/SS (1-4)
+		p_hs_bint		playback bInterval for HS/SS (1-4: fixed, 0: auto)
 		p_mute_present		playback mute control enable
 		p_volume_present	playback volume control enable
 		p_volume_min		playback volume control min value
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
index bd91191683be..c6d034abce3a 100644
--- a/Documentation/usb/gadget-testing.rst
+++ b/Documentation/usb/gadget-testing.rst
@@ -734,7 +734,7 @@ The uac2 function provides these attributes in its function directory:
 	c_volume_min     capture volume control min value (in 1/256 dB)
 	c_volume_max     capture volume control max value (in 1/256 dB)
 	c_volume_res     capture volume control resolution (in 1/256 dB)
-	c_hs_bint        capture bInterval for HS/SS (1-4)
+	c_hs_bint        capture bInterval for HS/SS (1-4: fixed, 0: auto)
 	fb_max           maximum extra bandwidth in async mode
 	p_chmask         playback channel mask
 	p_srate          list of playback sampling rates (comma-separated)
@@ -744,7 +744,7 @@ The uac2 function provides these attributes in its function directory:
 	p_volume_min     playback volume control min value (in 1/256 dB)
 	p_volume_max     playback volume control max value (in 1/256 dB)
 	p_volume_res     playback volume control resolution (in 1/256 dB)
-	p_hs_bint        playback bInterval for HS/SS (1-4)
+	p_hs_bint        playback bInterval for HS/SS (1-4: fixed, 0: auto)
 	req_number       the number of pre-allocated request for both capture
 	                 and playback
 	function_name    name of the interface
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 34bb6c9a9023..48d6fb26bb19 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -664,29 +664,11 @@ static int get_max_srate(const int *srates)
 	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)
+static int get_max_bw_for_bint(const struct f_uac2_opts *uac2_opts,
+	u8 bint, unsigned int factor, bool is_playback)
 {
 	int chmask, srate, ssize;
-	u16 max_size_bw, max_size_ep;
-	unsigned int factor;
-
-	switch (speed) {
-	case USB_SPEED_FULL:
-		max_size_ep = 1023;
-		factor = 1000;
-		break;
-
-	case USB_SPEED_HIGH:
-	case USB_SPEED_SUPER:
-		max_size_ep = 1024;
-		factor = 8000;
-		break;
-
-	default:
-		return -EINVAL;
-	}
+	u16 max_size_bw;
 
 	if (is_playback) {
 		chmask = uac2_opts->p_chmask;
@@ -704,14 +686,76 @@ static int set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 		srate = srate * (1000 + uac2_opts->fb_max) / 1000;
 		// updated srate is always bigger, therefore DIV_ROUND_UP always yields +1
 		max_size_bw = num_channels(chmask) * ssize *
-			(DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1))));
+			(DIV_ROUND_UP(srate, factor / (1 << (bint - 1))));
 	} else {
 		// adding 1 frame provision for Win10
 		max_size_bw = num_channels(chmask) * ssize *
-			(DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1))) + 1);
+			(DIV_ROUND_UP(srate, factor / (1 << (bint - 1))) + 1);
 	}
-	ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw,
-						    max_size_ep));
+	return max_size_bw;
+}
+
+static int set_ep_max_packet_size_bint(struct device *dev, const struct f_uac2_opts *uac2_opts,
+	struct usb_endpoint_descriptor *ep_desc,
+	enum usb_device_speed speed, bool is_playback)
+{
+	u16 max_size_bw, max_size_ep;
+	u8 bint, opts_bint;
+	char *dir;
+
+	switch (speed) {
+	case USB_SPEED_FULL:
+		max_size_ep = 1023;
+		// fixed
+		bint = ep_desc->bInterval;
+		max_size_bw = get_max_bw_for_bint(uac2_opts, bint, 1000, is_playback);
+		break;
+
+	case USB_SPEED_HIGH:
+	case USB_SPEED_SUPER:
+		max_size_ep = 1024;
+		if (is_playback)
+			opts_bint = uac2_opts->p_hs_bint;
+		else
+			opts_bint = uac2_opts->c_hs_bint;
+
+		if (opts_bint > 0) {
+			/* fixed bint */
+			bint = opts_bint;
+			max_size_bw = get_max_bw_for_bint(uac2_opts, bint, 8000, is_playback);
+		} else {
+			/* checking bInterval from 4 to 1 whether the required bandwidth fits */
+			for (bint = 4; bint > 0; --bint) {
+				max_size_bw = get_max_bw_for_bint(
+					uac2_opts, bint, 8000, is_playback);
+				if (max_size_bw <= max_size_ep)
+					break;
+			}
+		}
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	if (is_playback)
+		dir = "Playback";
+	else
+		dir = "Capture";
+
+	if (max_size_bw <= max_size_ep)
+		dev_dbg(dev,
+			"%s: Will use maxpctksize %d and bInterval %d\n",
+			dir, max_size_bw, bint);
+	else {
+		dev_warn(dev,
+			"%s: Req. maxpcktsize %d at bInterval %d > max ISOC %d, may drop data!\n",
+			dir, max_size_bw, bint, max_size_ep);
+		max_size_bw = max_size_ep;
+	}
+
+	ep_desc->wMaxPacketSize = cpu_to_le16(max_size_bw);
+	ep_desc->bInterval = bint;
 
 	return 0;
 }
@@ -965,13 +1009,13 @@ static int afunc_validate_opts(struct g_audio *agdev, struct device *dev)
 			return -EINVAL;
 	}
 
-	if ((opts->p_hs_bint < 1) || (opts->p_hs_bint > 4)) {
-		dev_err(dev, "Error: incorrect playback HS/SS bInterval (1-4)\n");
+	if ((opts->p_hs_bint < 0) || (opts->p_hs_bint > 4)) {
+		dev_err(dev, "Error: incorrect playback HS/SS bInterval (1-4: fixed, 0: auto)\n");
 		return -EINVAL;
 	}
 
-	if ((opts->c_hs_bint < 1) || (opts->c_hs_bint > 4)) {
-		dev_err(dev, "Error: incorrect capture HS/SS bInterval (1-4)\n");
+	if ((opts->c_hs_bint < 0) || (opts->c_hs_bint > 4)) {
+		dev_err(dev, "Error: incorrect capture HS/SS bInterval (1-4: fixed, 0: auto)\n");
 		return -EINVAL;
 	}
 
@@ -1141,43 +1185,43 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	ss_epout_desc.bInterval = uac2_opts->c_hs_bint;
 
 	/* Calculate wMaxPacketSize according to audio bandwidth */
-	ret = set_ep_max_packet_size(uac2_opts, &fs_epin_desc, USB_SPEED_FULL,
-				     true);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &fs_epin_desc,
+					USB_SPEED_FULL, true);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
 	}
 
-	ret = set_ep_max_packet_size(uac2_opts, &fs_epout_desc, USB_SPEED_FULL,
-				     false);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &fs_epout_desc,
+					USB_SPEED_FULL, false);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
 	}
 
-	ret = set_ep_max_packet_size(uac2_opts, &hs_epin_desc, USB_SPEED_HIGH,
-				     true);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &hs_epin_desc,
+					USB_SPEED_HIGH, true);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
 	}
 
-	ret = set_ep_max_packet_size(uac2_opts, &hs_epout_desc, USB_SPEED_HIGH,
-				     false);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &hs_epout_desc,
+					USB_SPEED_HIGH, false);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
 	}
 
-	ret = set_ep_max_packet_size(uac2_opts, &ss_epin_desc, USB_SPEED_SUPER,
-				     true);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &ss_epin_desc,
+					USB_SPEED_SUPER, true);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
 	}
 
-	ret = set_ep_max_packet_size(uac2_opts, &ss_epout_desc, USB_SPEED_SUPER,
-				     false);
+	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &ss_epout_desc,
+					USB_SPEED_SUPER, false);
 	if (ret < 0) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return ret;
diff --git a/drivers/usb/gadget/function/u_uac2.h b/drivers/usb/gadget/function/u_uac2.h
index 733a0e0945fb..0510c9bad58d 100644
--- a/drivers/usb/gadget/function/u_uac2.h
+++ b/drivers/usb/gadget/function/u_uac2.h
@@ -19,11 +19,11 @@
 #define UAC2_DEF_PCHMASK 0x3
 #define UAC2_DEF_PSRATE 48000
 #define UAC2_DEF_PSSIZE 2
-#define UAC2_DEF_PHSBINT 4
+#define UAC2_DEF_PHSBINT 0
 #define UAC2_DEF_CCHMASK 0x3
 #define UAC2_DEF_CSRATE 64000
 #define UAC2_DEF_CSSIZE 2
-#define UAC2_DEF_CHSBINT 4
+#define UAC2_DEF_CHSBINT 0
 #define UAC2_DEF_CSYNC		USB_ENDPOINT_SYNC_ASYNC
 
 #define UAC2_DEF_MUTE_PRESENT	1
-- 
2.25.1

[PATCH 4/4] usb: gadget: f_uac2: Add speed names to bInterval dbg/warn

[Pavel Hofman]

Add speed names for better clarity of dgb/warn messages from max packet
size/bInterval checks.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
---
 drivers/usb/gadget/function/f_uac2.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 48d6fb26bb19..ce3ca7e62e2a 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -124,6 +124,16 @@ static struct usb_string strings_fn[] = {
 	{ },
 };
 
+static const char *const speed_names[] = {
+	[USB_SPEED_UNKNOWN] = "UNKNOWN",
+	[USB_SPEED_LOW] = "LS",
+	[USB_SPEED_FULL] = "FS",
+	[USB_SPEED_HIGH] = "HS",
+	[USB_SPEED_WIRELESS] = "W",
+	[USB_SPEED_SUPER] = "SS",
+	[USB_SPEED_SUPER_PLUS] = "SS+",
+};
+
 static struct usb_gadget_strings str_fn = {
 	.language = 0x0409,	/* en-us */
 	.strings = strings_fn,
@@ -745,12 +755,12 @@ static int set_ep_max_packet_size_bint(struct device *dev, const struct f_uac2_o
 
 	if (max_size_bw <= max_size_ep)
 		dev_dbg(dev,
-			"%s: Will use maxpctksize %d and bInterval %d\n",
-			dir, max_size_bw, bint);
+			"%s %s: Would use maxpctksize %d and bInterval %d\n",
+			speed_names[speed], dir, max_size_bw, bint);
 	else {
 		dev_warn(dev,
-			"%s: Req. maxpcktsize %d at bInterval %d > max ISOC %d, may drop data!\n",
-			dir, max_size_bw, bint, max_size_ep);
+			"%s %s: Req. maxpcktsize %d at bInterval %d > max ISOC %d, may drop data!\n",
+			speed_names[speed], dir, max_size_bw, bint, max_size_ep);
 		max_size_bw = max_size_ep;
 	}
 
-- 
2.25.1