From 71be4f81e97fe1f42c48a6dfc411dc6d3c18687f Mon Sep 17 00:00:00 2001 From: Aleksey Gorelov Date: Thu, 19 Jun 2008 15:22:17 -0700 Subject: [PATCH] USB: debug port converter does not accept more than 8 byte packets USB debug port only supports 8 byte rx/tx packets. Although spec implies that "if a packet larger than eight bytes is received from the remote computer, the device must break the larger packet into eight-byte packets before sending the data to the Debug Port", the real PLX NET20DC device does not handle it right - data is corrupted on debug port end if serial interface sends >8 byte urbs. Patch below fixes the issue by limiting tx urb to 8 byte. Signed off by: Aleks Gorelov Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/usb_debug.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/usb/serial/usb_debug.c b/drivers/usb/serial/usb_debug.c index f9fc926..9ca4d4d 100644 --- a/drivers/usb/serial/usb_debug.c +++ b/drivers/usb/serial/usb_debug.c @@ -15,6 +15,8 @@ #include #include +#define USB_DEBUG_MAX_PACKET_SIZE 8 + static struct usb_device_id id_table [] = { { USB_DEVICE(0x0525, 0x127a) }, { }, @@ -29,6 +31,12 @@ static struct usb_driver debug_driver = { .no_dynamic_id = 1, }; +int usb_debug_open(struct usb_serial_port *port, struct file *filp) +{ + port->bulk_out_size = USB_DEBUG_MAX_PACKET_SIZE; + return usb_serial_generic_open(port, filp); +} + static struct usb_serial_driver debug_device = { .driver = { .owner = THIS_MODULE, @@ -36,6 +44,7 @@ static struct usb_serial_driver debug_device = { }, .id_table = id_table, .num_ports = 1, + .open = usb_debug_open, }; static int __init debug_init(void) -- 2.7.4