[alsa-devel] [PATCH v2] ALSA: usb-audio: Fix parameter block size for UAC2 control requests
Julian Scheel
julian at jusst.de
Fri Aug 14 16:14:45 CEST 2015
USB Audio Class version 2.0 supports three different parameter block sizes for
CUR requests, which are 1 byte (5.2.3.1 Layout 1 Parameter Block), 2 bytes
(5.2.3.2 Layout 2 Parameter Block) and 4 bytes (5.2.3.3 Layout 3 Parameter
Block). Use the correct size according to the specific control as it was
already done for UACv1. The allocated block size for control requests is
increased to support the 4 byte worst case.
Signed-off-by: Julian Scheel <julian at jusst.de>
---
Changes in v2:
- Removed superfluous int32 checks
- Check control value length in function
- Compare against 0
- Use a tmp variable to access audio_feature_info[control-1]
Thanks for review by Takashi Iwai :)
---
sound/usb/mixer.c | 64 ++++++++++++++++++++++++++++++++++++++-----------------
sound/usb/mixer.h | 2 ++
2 files changed, 46 insertions(+), 20 deletions(-)
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 4a49944..7046f54 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -282,6 +282,21 @@ static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
return val;
}
+static int uac2_ctl_value_size(int val_type)
+{
+ switch (val_type) {
+ case USB_MIXER_S32:
+ case USB_MIXER_U32:
+ return 4;
+ case USB_MIXER_S16:
+ case USB_MIXER_U16:
+ return 2;
+ default:
+ return 1;
+ }
+ return 0; /* unreachable */
+}
+
/*
* retrieve a mixer value
@@ -328,14 +343,14 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
int validx, int *value_ret)
{
struct snd_usb_audio *chip = cval->head.mixer->chip;
- unsigned char buf[2 + 3 * sizeof(__u16)]; /* enough space for one range */
+ unsigned char buf[4 + 3 * sizeof(__u32)]; /* enough space for one range */
unsigned char *val;
int idx = 0, ret, size;
__u8 bRequest;
if (request == UAC_GET_CUR) {
bRequest = UAC2_CS_CUR;
- size = sizeof(__u16);
+ size = uac2_ctl_value_size(cval->val_type);
} else {
bRequest = UAC2_CS_RANGE;
size = sizeof(buf);
@@ -446,7 +461,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
int request, int validx, int value_set)
{
struct snd_usb_audio *chip = cval->head.mixer->chip;
- unsigned char buf[2];
+ unsigned char buf[4];
int idx = 0, val_len, err, timeout = 10;
validx += cval->idx_off;
@@ -454,8 +469,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
if (cval->head.mixer->protocol == UAC_VERSION_1) {
val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
} else { /* UAC_VERSION_2 */
- /* audio class v2 controls are always 2 bytes in size */
- val_len = sizeof(__u16);
+ val_len = uac2_ctl_value_size(cval->val_type);
/* FIXME */
if (request != UAC_SET_CUR) {
@@ -469,6 +483,8 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
value_set = convert_bytes_value(cval, value_set);
buf[0] = value_set & 0xff;
buf[1] = (value_set >> 8) & 0xff;
+ buf[2] = (value_set >> 16) & 0xff;
+ buf[3] = (value_set >> 24) & 0xff;
err = snd_usb_autoresume(chip);
if (err < 0)
return -EIO;
@@ -799,24 +815,25 @@ static int check_input_term(struct mixer_build *state, int id,
/* feature unit control information */
struct usb_feature_control_info {
const char *name;
- unsigned int type; /* control type (mute, volume, etc.) */
+ int type; /* data type for uac1 */
+ int type_uac2; /* data type for uac2 if different from uac1, else -1 */
};
static struct usb_feature_control_info audio_feature_info[] = {
- { "Mute", USB_MIXER_INV_BOOLEAN },
- { "Volume", USB_MIXER_S16 },
- { "Tone Control - Bass", USB_MIXER_S8 },
- { "Tone Control - Mid", USB_MIXER_S8 },
- { "Tone Control - Treble", USB_MIXER_S8 },
- { "Graphic Equalizer", USB_MIXER_S8 }, /* FIXME: not implemeted yet */
- { "Auto Gain Control", USB_MIXER_BOOLEAN },
- { "Delay Control", USB_MIXER_U16 }, /* FIXME: U32 in UAC2 */
- { "Bass Boost", USB_MIXER_BOOLEAN },
- { "Loudness", USB_MIXER_BOOLEAN },
+ { "Mute", USB_MIXER_INV_BOOLEAN, -1 },
+ { "Volume", USB_MIXER_S16, -1 },
+ { "Tone Control - Bass", USB_MIXER_S8, -1 },
+ { "Tone Control - Mid", USB_MIXER_S8, -1 },
+ { "Tone Control - Treble", USB_MIXER_S8, -1 },
+ { "Graphic Equalizer", USB_MIXER_S8, -1 }, /* FIXME: not implemeted yet */
+ { "Auto Gain Control", USB_MIXER_BOOLEAN, -1 },
+ { "Delay Control", USB_MIXER_U16, USB_MIXER_U32 },
+ { "Bass Boost", USB_MIXER_BOOLEAN, -1 },
+ { "Loudness", USB_MIXER_BOOLEAN, -1 },
/* UAC2 specific */
- { "Input Gain Control", USB_MIXER_S16 },
- { "Input Gain Pad Control", USB_MIXER_S16 },
- { "Phase Inverter Control", USB_MIXER_BOOLEAN },
+ { "Input Gain Control", USB_MIXER_S16, -1 },
+ { "Input Gain Pad Control", USB_MIXER_S16, -1 },
+ { "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
};
/* private_free callback */
@@ -1216,6 +1233,7 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
int readonly_mask)
{
struct uac_feature_unit_descriptor *desc = raw_desc;
+ struct usb_feature_control_info *ctl_info;
unsigned int len = 0;
int mapped_name = 0;
int nameid = uac_feature_unit_iFeature(desc);
@@ -1241,7 +1259,13 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
cval->control = control;
cval->cmask = ctl_mask;
- cval->val_type = audio_feature_info[control-1].type;
+ ctl_info = &audio_feature_info[control-1];
+ if (state->mixer->protocol == UAC_VERSION_1)
+ cval->val_type = ctl_info->type;
+ else /* UAC_VERSION_2 */
+ cval->val_type = ctl_info->type_uac2 >= 0 ?
+ ctl_info->type_uac2 : ctl_info->type;
+
if (ctl_mask == 0) {
cval->channels = 1; /* master channel */
cval->master_readonly = readonly_mask;
diff --git a/sound/usb/mixer.h b/sound/usb/mixer.h
index d3268f0..3417ef3 100644
--- a/sound/usb/mixer.h
+++ b/sound/usb/mixer.h
@@ -33,6 +33,8 @@ enum {
USB_MIXER_U8,
USB_MIXER_S16,
USB_MIXER_U16,
+ USB_MIXER_S32,
+ USB_MIXER_U32,
};
typedef void (*usb_mixer_elem_dump_func_t)(struct snd_info_buffer *buffer,
--
2.5.0
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