serial: 8250: extract serial8250_startup_special()

Let the serial8250_do_startup() code handle the special ports (16C950,
DA830, RSA) startup in a separate function:
serial8250_startup_special().

And instead of multiple if-else-if, use switch-case. So that it can be
easily checked for PORT_RSA now too.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250611100319.186924-14-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 476f5fc5023754b8f764a60f0fcac88e343e1c55..21ff56a31b56c7f74e680cd823b7347e15449bb8 100644 (file)
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2111,27 +2111,13 @@ static void serial8250_put_poll_char(struct uart_port *port,
 
 #endif /* CONFIG_CONSOLE_POLL */
 
-int serial8250_do_startup(struct uart_port *port)
+static void serial8250_startup_special(struct uart_port *port)
 {
        struct uart_8250_port *up = up_to_u8250p(port);
        unsigned long flags;
-       unsigned char iir;
-       int retval;
-       u16 lsr;
-
-       if (!port->fifosize)
-               port->fifosize = uart_config[port->type].fifo_size;
-       if (!up->tx_loadsz)
-               up->tx_loadsz = uart_config[port->type].tx_loadsz;
-       if (!up->capabilities)
-               up->capabilities = uart_config[port->type].flags;
-       up->mcr = 0;
-
-       if (port->iotype != up->cur_iotype)
-               set_io_from_upio(port);
 
-       serial8250_rpm_get(up);
-       if (port->type == PORT_16C950) {
+       switch (port->type) {
+       case PORT_16C950:
                /*
                 * Wake up and initialize UART
                 *
@@ -2148,9 +2134,8 @@ int serial8250_do_startup(struct uart_port *port)
                serial_port_out(port, UART_EFR, UART_EFR_ECB);
                serial_port_out(port, UART_LCR, 0);
                uart_port_unlock_irqrestore(port, flags);
-       }
-
-       if (port->type == PORT_DA830) {
+               break;
+       case PORT_DA830:
                /*
                 * Reset the port
                 *
@@ -2167,9 +2152,35 @@ int serial8250_do_startup(struct uart_port *port)
                                UART_DA830_PWREMU_MGMT_UTRST |
                                UART_DA830_PWREMU_MGMT_URRST |
                                UART_DA830_PWREMU_MGMT_FREE);
+               break;
+       case PORT_RSA:
+               rsa_enable(up);
+               break;
        }
+}
+
+int serial8250_do_startup(struct uart_port *port)
+{
+       struct uart_8250_port *up = up_to_u8250p(port);
+       unsigned long flags;
+       unsigned char iir;
+       int retval;
+       u16 lsr;
+
+       if (!port->fifosize)
+               port->fifosize = uart_config[port->type].fifo_size;
+       if (!up->tx_loadsz)
+               up->tx_loadsz = uart_config[port->type].tx_loadsz;
+       if (!up->capabilities)
+               up->capabilities = uart_config[port->type].flags;
+       up->mcr = 0;
+
+       if (port->iotype != up->cur_iotype)
+               set_io_from_upio(port);
+
+       serial8250_rpm_get(up);
 
-       rsa_enable(up);
+       serial8250_startup_special(port);
 
        /*
         * Clear the FIFO buffers and disable them.