[alsa-devel] [PATCH] ALSA: usb-audio: Fix parameter block size for UAC2 control requests
Julian Scheel
julian at jusst.de
Fri Aug 14 15:45:58 CEST 2015
Am 14.08.2015 um 15:17 schrieb Takashi Iwai:
> On Thu, 13 Aug 2015 13:04:46 +0200,
> Julian Scheel wrote:
>>
>> 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>
>> ---
>> sound/usb/mixer.c | 83 +++++++++++++++++++++++++++++++++++++++++--------------
>> sound/usb/mixer.h | 2 ++
>> 2 files changed, 65 insertions(+), 20 deletions(-)
>>
>> diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
>> index 4a49944..675725b 100644
>> --- a/sound/usb/mixer.c
>> +++ b/sound/usb/mixer.c
>> @@ -233,6 +233,14 @@ static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
>> if (val >= 0x8000)
>> val -= 0x10000;
>> break;
>> + case USB_MIXER_U32:
>> + val &= 0xffffffff;
>> + break;
>> + case USB_MIXER_S32:
>> + val &= 0xffffffff;
>> + if (val >= 0x80000000)
>> + val -= 0x100000000;
>> + break;
>
> All these are superfluous, as int on Linux is always 32bit.
Of course. Thanks.
>> }
>> return val;
>> }
>> @@ -253,6 +261,9 @@ static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
>> case USB_MIXER_S16:
>> case USB_MIXER_U16:
>> return val & 0xffff;
>> + case USB_MIXER_S32:
>> + case USB_MIXER_U32:
>> + return val & 0xffffffff;
>
> Ditto.
>
>
>> }
>> return 0; /* not reached */
>> }
>> @@ -328,14 +339,26 @@ 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);
>> + switch (cval->val_type) {
>> + case USB_MIXER_S32:
>> + case USB_MIXER_U32:
>> + size = 4;
>> + break;
>> + case USB_MIXER_S16:
>> + case USB_MIXER_U16:
>> + size = 2;
>> + break;
>> + default:
>> + size = 1;
>> + break;
>
> Please split this into a small helper function,
> e.g. uac2_ctl_value_size(). The same stuff is used in below, too.
Ack.
>> + }
>> } else {
>> bRequest = UAC2_CS_RANGE;
>> size = sizeof(buf);
>> @@ -446,7 +469,7 @@ 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 +477,19 @@ 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);
>> + switch (cval->val_type) {
>> + case USB_MIXER_S32:
>> + case USB_MIXER_U32:
>> + val_len = 4;
>> + break;
>> + case USB_MIXER_S16:
>> + case USB_MIXER_U16:
>> + val_len = 2;
>> + break;
>> + default:
>> + val_len = 1;
>> + break;
>> + }
>>
>> /* FIXME */
>> if (request != UAC_SET_CUR) {
>> @@ -469,6 +503,8 @@ 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;
>
> It's not smart but OK, just a subtle matter...
Hm, what would you like better?
>> err = snd_usb_autoresume(chip);
>> if (err < 0)
>> return -EIO;
>> @@ -799,24 +835,25 @@ 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 */
>> @@ -1241,7 +1278,13 @@ 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;
>> + if (state->mixer->protocol == UAC_VERSION_1)
>> + cval->val_type = audio_feature_info[control-1].type;
>> + else /* UAC_VERSION_2 */
>> + cval->val_type = audio_feature_info[control-1].type_uac2 > -1 ?
>
> Usually ">= 0" is used.
Ack.
>> + audio_feature_info[control-1].type_uac2 :
>> + audio_feature_info[control-1].type;
>
> Since audio_feature_info[control-1] is referred so many times, it's
> better to put in a temporary variable.
Ack.
Thanks for reviewing!
-Julian
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