diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c index 6d8ef3aa99b5..3b225430bfad 100644 --- a/sound/usb/mixer_scarlett_gen2.c +++ b/sound/usb/mixer_scarlett_gen2.c @@ -118,6 +118,8 @@ #define SCARLETT2_MIXER_MAX_VALUE \ ((SCARLETT2_MIXER_MAX_DB - SCARLETT2_MIXER_MIN_DB) * 2) +#include + /* map from (dB + 80) * 2 to mixer value * for dB in 0 .. 172: int(8192 * pow(10, ((dB - 160) / 2 / 20))) */ @@ -591,6 +593,8 @@ static int scarlett2_usb( u16 req_buf_size = sizeof(struct scarlett2_usb_packet) + req_size; u16 resp_buf_size = sizeof(struct scarlett2_usb_packet) + resp_size; struct scarlett2_usb_packet *req = NULL, *resp = NULL; + int retries = 0; + const int max_retries = 5; int err = 0; req = kmalloc(req_buf_size, GFP_KERNEL); @@ -614,6 +618,7 @@ static int scarlett2_usb( if (req_size) memcpy(req->data, req_data, req_size); +retry: err = snd_usb_ctl_msg(mixer->chip->dev, usb_sndctrlpipe(mixer->chip->dev, 0), SCARLETT2_USB_VENDOR_SPECIFIC_CMD_REQ, @@ -624,6 +629,10 @@ static int scarlett2_usb( req_buf_size); if (err != req_buf_size) { + if (err == -EPROTO && ++retries <= max_retries) { + msleep(5 * (1 << (retries - 1))); + goto retry; + } usb_audio_err( mixer->chip, "Scarlett Gen 2 USB request result cmd %x was %d\n",