From 0238d2b4a4c7bb1b2268e1ef789629878e16ab02 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Thu, 12 Jul 2018 09:57:00 +0800 Subject: [PATCH] serial: 8250: introduce get_divisor() and set_divisor() hook Add these two hooks so that they can be overridden with driver specific implementations. Signed-off-by: Jisheng Zhang Reviewed-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_core.c | 4 ++++ drivers/tty/serial/8250/8250_port.c | 27 +++++++++++++++++++++++---- include/linux/serial_core.h | 7 +++++++ 3 files changed, 34 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 9342fc2ee7df..a0bb77290747 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1023,6 +1023,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up) uart->port.get_mctrl = up->port.get_mctrl; if (up->port.set_mctrl) uart->port.set_mctrl = up->port.set_mctrl; + if (up->port.get_divisor) + uart->port.get_divisor = up->port.get_divisor; + if (up->port.set_divisor) + uart->port.set_divisor = up->port.set_divisor; if (up->port.startup) uart->port.startup = up->port.startup; if (up->port.shutdown) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 709fe6b4265c..ce0dc17f18ee 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2498,9 +2498,9 @@ static unsigned int npcm_get_divisor(struct uart_8250_port *up, return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2; } -static unsigned int serial8250_get_divisor(struct uart_port *port, - unsigned int baud, - unsigned int *frac) +static unsigned int serial8250_do_get_divisor(struct uart_port *port, + unsigned int baud, + unsigned int *frac) { struct uart_8250_port *up = up_to_u8250p(port); unsigned int quot; @@ -2532,6 +2532,16 @@ static unsigned int serial8250_get_divisor(struct uart_port *port, return quot; } +static unsigned int serial8250_get_divisor(struct uart_port *port, + unsigned int baud, + unsigned int *frac) +{ + if (port->get_divisor) + return port->get_divisor(port, baud, frac); + + return serial8250_do_get_divisor(port, baud, frac); +} + static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, tcflag_t c_cflag) { @@ -2570,7 +2580,7 @@ static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, return cval; } -static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, +static void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud, unsigned int quot, unsigned int quot_frac) { struct uart_8250_port *up = up_to_u8250p(port); @@ -2603,6 +2613,15 @@ static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, } } +static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, + unsigned int quot, unsigned int quot_frac) +{ + if (port->set_divisor) + port->set_divisor(port, baud, quot, quot_frac); + else + serial8250_do_set_divisor(port, baud, quot, quot_frac); +} + static unsigned int serial8250_get_baud_rate(struct uart_port *port, struct ktermios *termios, struct ktermios *old) diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 06ea4eeb09ab..406edae44ca3 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -127,6 +127,13 @@ struct uart_port { struct ktermios *); unsigned int (*get_mctrl)(struct uart_port *); void (*set_mctrl)(struct uart_port *, unsigned int); + unsigned int (*get_divisor)(struct uart_port *, + unsigned int baud, + unsigned int *frac); + void (*set_divisor)(struct uart_port *, + unsigned int baud, + unsigned int quot, + unsigned int quot_frac); int (*startup)(struct uart_port *port); void (*shutdown)(struct uart_port *port); void (*throttle)(struct uart_port *port); -- 2.45.2