diff options
Diffstat (limited to 'drivers/usb/serial/usb_debug.c')
| -rw-r--r-- | drivers/usb/serial/usb_debug.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/usb/serial/usb_debug.c b/drivers/usb/serial/usb_debug.c index 6c9cbb59552a..614800972dc3 100644 --- a/drivers/usb/serial/usb_debug.c +++ b/drivers/usb/serial/usb_debug.c @@ -15,7 +15,19 @@ #include <linux/usb.h> #include <linux/usb/serial.h> +#define URB_DEBUG_MAX_IN_FLIGHT_URBS 4000 #define USB_DEBUG_MAX_PACKET_SIZE 8 +#define USB_DEBUG_BRK_SIZE 8 +static char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = { + 0x00, + 0xff, + 0x01, + 0xfe, + 0x00, + 0xfe, + 0x01, + 0xff, +}; static struct usb_device_id id_table [] = { { USB_DEVICE(0x0525, 0x127a) }, @@ -38,6 +50,32 @@ static int usb_debug_open(struct tty_struct *tty, struct usb_serial_port *port, return usb_serial_generic_open(tty, port, filp); } +/* This HW really does not support a serial break, so one will be + * emulated when ever the break state is set to true. + */ +static void usb_debug_break_ctl(struct tty_struct *tty, int break_state) +{ + struct usb_serial_port *port = tty->driver_data; + if (!break_state) + return; + usb_serial_generic_write(tty, port, USB_DEBUG_BRK, USB_DEBUG_BRK_SIZE); +} + +static void usb_debug_read_bulk_callback(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + + if (urb->actual_length == USB_DEBUG_BRK_SIZE && + memcmp(urb->transfer_buffer, USB_DEBUG_BRK, + USB_DEBUG_BRK_SIZE) == 0) { + usb_serial_handle_break(port); + usb_serial_generic_resubmit_read_urb(port, GFP_ATOMIC); + return; + } + + usb_serial_generic_read_bulk_callback(urb); +} + static struct usb_serial_driver debug_device = { .driver = { .owner = THIS_MODULE, @@ -46,6 +84,9 @@ static struct usb_serial_driver debug_device = { .id_table = id_table, .num_ports = 1, .open = usb_debug_open, + .max_in_flight_urbs = URB_DEBUG_MAX_IN_FLIGHT_URBS, + .break_ctl = usb_debug_break_ctl, + .read_bulk_callback = usb_debug_read_bulk_callback, }; static int __init debug_init(void) |