From: San Mehat <san@xxxxxxxxxx> serial_core: Add wake_peer uart operation Add wake_peer which is called before starting UART TX. The idea here is to provide a mechanism where we can wakeup our peer before sending data. Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Jiri Slaby <jslaby@xxxxxxx> Cc: linux-serial@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: Android Kernel Team <kernel-team@xxxxxxxxxxx> Cc: John Stultz <john.stultz@xxxxxxxxxx> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> Signed-off-by: San Mehat <san@xxxxxxxxxx> [Kiran: Added context to commit message] Signed-off-by: Kiran Raparthy <kiran.kumar@xxxxxxxxxx> --- This is one of the number of patches from the Android AOSP common.git tree, which is used on almost all Android devices. I wanted to submit it for review to see if it should go upstream. drivers/tty/serial/serial_core.c | 3 +++ include/linux/serial_core.h | 1 + 2 files changed, 4 insertions(+) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index df3a8c7..dc45c4b 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -95,6 +95,9 @@ static void __uart_start(struct tty_struct *tty) struct uart_state *state = tty->driver_data; struct uart_port *port = state->uart_port; + if (port->ops->wake_peer) + port->ops->wake_peer(port); + if (!uart_tx_stopped(port)) port->ops->start_tx(port); } diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 21c2e05..219b6a3 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -66,6 +66,7 @@ struct uart_ops { void (*set_ldisc)(struct uart_port *, int new); void (*pm)(struct uart_port *, unsigned int state, unsigned int oldstate); + void (*wake_peer)(struct uart_port *); /* * Return a string describing the type of the port -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html