mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
serial: avoid waking up closed serial ports on resume
When we boot, serial ports remain in low power mode until they're used either by userspace or for the kernel console. However, if you suspend the system, and then resume, all serial ports will be taken out of low power mode. This is bad news for embedded devices where this can mean higher power consumption. Only bring a serial port out of low power mode if the port is being used as the kernel console, or is in use by userspace. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
74a1974172
commit
9d778a6937
1 changed files with 2 additions and 2 deletions
|
@ -2029,8 +2029,6 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
|
||||||
}
|
}
|
||||||
port->suspended = 0;
|
port->suspended = 0;
|
||||||
|
|
||||||
uart_change_pm(state, 0);
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* Re-enable the console device after suspending.
|
* Re-enable the console device after suspending.
|
||||||
*/
|
*/
|
||||||
|
@ -2049,6 +2047,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
|
||||||
if (state->info && state->info->tty && termios.c_cflag == 0)
|
if (state->info && state->info->tty && termios.c_cflag == 0)
|
||||||
termios = *state->info->tty->termios;
|
termios = *state->info->tty->termios;
|
||||||
|
|
||||||
|
uart_change_pm(state, 0);
|
||||||
port->ops->set_termios(port, &termios, NULL);
|
port->ops->set_termios(port, &termios, NULL);
|
||||||
console_start(port->cons);
|
console_start(port->cons);
|
||||||
}
|
}
|
||||||
|
@ -2057,6 +2056,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
|
||||||
const struct uart_ops *ops = port->ops;
|
const struct uart_ops *ops = port->ops;
|
||||||
int ret;
|
int ret;
|
||||||
|
|
||||||
|
uart_change_pm(state, 0);
|
||||||
ops->set_mctrl(port, 0);
|
ops->set_mctrl(port, 0);
|
||||||
ret = ops->startup(port);
|
ret = ops->startup(port);
|
||||||
if (ret == 0) {
|
if (ret == 0) {
|
||||||
|
|
Loading…
Reference in a new issue