From: Sebastian Frias Date: Fri, 18 Dec 2015 16:40:05 +0000 (+0100) Subject: 8250: use callbacks to access UART_DLL/UART_DLM X-Git-Tag: v3.2.80~111 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=8fb7e4488e20229828e54187b6aa3ed5cd7cb315 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 Reviewed-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: - Adjust filename - We're using serial_{in,out}p for 8-bit I/O] Signed-off-by: Ben Hutchings --- diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index 33601f891fd7..07cfec56db00 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -777,22 +777,16 @@ 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_inp(p, UART_LCR); serial_outp(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_inp(p, UART_DLL); - old_dlm = serial_inp(p, UART_DLM); - - serial_outp(p, UART_DLL, 0); - serial_outp(p, UART_DLM, 0); - - id = serial_inp(p, UART_DLL) | serial_inp(p, UART_DLM) << 8; - - serial_outp(p, UART_DLL, old_dll); - serial_outp(p, UART_DLM, old_dlm); serial_outp(p, UART_LCR, old_lcr); return id;