From: Johan Hovold johan@kernel.org
commit df7b16d1c00ecb3da3a30c999cdb39f273c99a2f upstream.
This reverts commit 3c18e9baee0ef97510dcda78c82285f52626764b.
These devices do not appear to send a zero-length packet when the transfer size is a multiple of the bulk-endpoint max-packet size. This means that incoming data may not be processed by the driver until a short packet is received or the receive buffer is full.
Revert back to using endpoint-sized receive buffers to avoid stalled reads.
Reported-by: Paul Größel pb.g@gmx.de Link: https://bugzilla.kernel.org/show_bug.cgi?id=214131 Fixes: 3c18e9baee0e ("USB: serial: ch341: fix character loss at high transfer rates") Cc: stable@vger.kernel.org Cc: Willy Tarreau w@1wt.eu Link: https://lore.kernel.org/r/20210824121926.19311-1-johan@kernel.org Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/serial/ch341.c | 1 - 1 file changed, 1 deletion(-)
--- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -851,7 +851,6 @@ static struct usb_serial_driver ch341_de .owner = THIS_MODULE, .name = "ch341-uart", }, - .bulk_in_size = 512, .id_table = id_table, .num_ports = 1, .open = ch341_open,