diff options
| author | Sebastian Frias <sf84@laposte.net> | 2015-12-18 19:40:05 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-12 19:08:49 +0300 |
| commit | fc0768092cebd0b70a08f5423263669ea3849ef9 (patch) | |
| tree | 51d4ad440fd55842f944c3b7ecbb5094553d663b /drivers/tty/serial/8250 | |
| parent | 456db805f77c45611caa217996dcb93f24afb2e5 (diff) | |
| download | linux-fc0768092cebd0b70a08f5423263669ea3849ef9.tar.xz | |
8250: use callbacks to access UART_DLL/UART_DLM
commit 0b41ce991052022c030fd868e03877700220b090 upstream.
Some UART HW has a single register combining UART_DLL/UART_DLM
(this was probably forgotten in the change that introduced the
callbacks, commit b32b19b8ffc05cbd3bf91c65e205f6a912ca15d9)
Fixes: b32b19b8ffc0 ("[SERIAL] 8250: set divisor register correctly ...")
Signed-off-by: Sebastian Frias <sf84@laposte.net>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250')
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 18 |
1 files changed, 6 insertions, 12 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 52d82d2ac726..56ccbcefdd85 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -713,22 +713,16 @@ static int size_fifo(struct uart_8250_port *up) */ static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p) { - unsigned char old_dll, old_dlm, old_lcr; - unsigned int id; + unsigned char old_lcr; + unsigned int id, old_dl; old_lcr = serial_in(p, UART_LCR); serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A); + old_dl = serial_dl_read(p); + serial_dl_write(p, 0); + id = serial_dl_read(p); + serial_dl_write(p, old_dl); - old_dll = serial_in(p, UART_DLL); - old_dlm = serial_in(p, UART_DLM); - - serial_out(p, UART_DLL, 0); - serial_out(p, UART_DLM, 0); - - id = serial_in(p, UART_DLL) | serial_in(p, UART_DLM) << 8; - - serial_out(p, UART_DLL, old_dll); - serial_out(p, UART_DLM, old_dlm); serial_out(p, UART_LCR, old_lcr); return id; |