This fixes the wMaxPacketSize of the audio gadget so it is in line with
USB Audio Format specification - section 2.3.1.2.1
Cc: Jack Pham <jackp@xxxxxxxxxxxxxx>
Cc: Pavel Hofman <pavel.hofman@xxxxxxxxxxx>
Fixes: e89bb4288378 ("usb: gadget: u_audio: add real feedback implementation")
Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
---
There was a mistake in my previous mail, rounding depends on the
synchronisation, not the stream direction.
drivers/usb/gadget/function/f_uac2.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index ae29ff2b2b68..c152efa30def 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -554,7 +554,7 @@ 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)
{
- int chmask, srate, ssize;
+ int chmask, srate, ssize, spf;
u16 max_size_bw, max_size_ep;
unsigned int factor;
@@ -584,11 +584,12 @@ static int set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
ssize = uac2_opts->c_ssize;
}
- if (!is_playback && (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC))
- srate = srate * (1000 + uac2_opts->fb_max) / 1000;
+ if (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ADAPTIVE)
+ spf = DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1)));
+ else
+ spf = (srate / (factor / (1 << (ep_desc->bInterval - 1)))) + 1;
- max_size_bw = num_channels(chmask) * ssize *
- DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1)));
+ max_size_bw = num_channels(chmask) * ssize * spf;
ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw,
max_size_ep));
--
2.33.0
