diff options
| author | Pavel Hofman <pavel.hofman@ivitera.com> | 2021-09-24 11:00:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-10-05 14:50:09 +0300 |
| commit | 0560c9c552c1815e7b480bc11fd785fefc82bb27 (patch) | |
| tree | e2020a19f40140b59471106f83e7999a956638df | |
| parent | 04d2b75537085cb0c85d73a2e0e50317bffa883f (diff) | |
| download | linux-0560c9c552c1815e7b480bc11fd785fefc82bb27.tar.xz | |
usb: gadget: f_uac2: fixed EP-IN wMaxPacketSize
Async feedback patches broke enumeration on Windows 10 previously fixed
by commit 789ea77310f0 ("usb: gadget: f_uac2: always increase endpoint
max_packet_size by one audio slot").
While the existing calculation for EP OUT capture for async mode yields
size+1 frame due to uac2_opts->fb_max > 0, playback side lost the +1
feature. Therefore the +1 frame addition must be re-introduced for
playback. Win10 enumerates the device only when both EP IN and EP OUT
max packet sizes are (at least) +1 frame.
Fixes: e89bb4288378 ("usb: gadget: u_audio: add real feedback implementation")
Cc: stable <stable@vger.kernel.org>
Tested-by: Henrik Enquist <henrik.enquist@gmail.com>
Tested-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20210924080027.5362-1-pavel.hofman@ivitera.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/function/f_uac2.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c index be864560bfea..ef55b8bb5870 100644 --- a/drivers/usb/gadget/function/f_uac2.c +++ b/drivers/usb/gadget/function/f_uac2.c @@ -674,11 +674,17 @@ 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)) + if (!is_playback && (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC)) { + // Win10 requires max packet size + 1 frame srate = srate * (1000 + uac2_opts->fb_max) / 1000; - - max_size_bw = num_channels(chmask) * ssize * - DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1))); + // 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)))); + } 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); + } ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw, max_size_ep)); |