diff options
| author | Sudhir Sreedharan <ssreedharan@mvista.com> | 2014-10-17 18:09:18 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-05 16:23:34 -0800 |
| commit | edf4edacb331caf326a2e0f15d81c549bd9bede7 (patch) | |
| tree | b895c7f580ed0ed57c8211aa77379bfb0338245f | |
| parent | 513e438581020334e0345561adeeeaefa36701be (diff) | |
tty: serial: 8250_core: restore the LCR register in set_sleep
In ST16650V2 based serial uarts, while initalizing the PM state,
LCR registers are being initialized to 0 in serial8250_set_sleep().
If console port is already initialized and being used, this will
throws garbage in the console.
Signed-off-by: Sudhir Sreedharan <ssreedharan@mvista.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index ca5cfdc1459a..b17048756941 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -595,6 +595,7 @@ static void serial8250_rpm_put_tx(struct uart_8250_port *p) */ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep) { + unsigned char lcr = 0, efr = 0; /* * Exar UARTs have a SLEEP register that enables or disables * each UART to enter sleep mode separately. On the XR17V35x the @@ -611,6 +612,8 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep) if (p->capabilities & UART_CAP_SLEEP) { if (p->capabilities & UART_CAP_EFR) { + lcr = serial_in(p, UART_LCR); + efr = serial_in(p, UART_EFR); serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); serial_out(p, UART_EFR, UART_EFR_ECB); serial_out(p, UART_LCR, 0); @@ -618,8 +621,8 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep) serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0); if (p->capabilities & UART_CAP_EFR) { serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); - serial_out(p, UART_EFR, 0); - serial_out(p, UART_LCR, 0); + serial_out(p, UART_EFR, efr); + serial_out(p, UART_LCR, lcr); } } out: |