tty: serial: meson: Move request the register region to probe
authorYu Tu <yu.tu@amlogic.com>
Fri, 25 Feb 2022 07:39:17 +0000 (15:39 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 26 Feb 2022 09:03:20 +0000 (10:03 +0100)
This simplifies resetting the UART controller during probe
and will make it easier to integrate the common clock code
which will require the registers at probe time as well.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/meson_uart.c

index 45e00d9..6b80e41 100644 (file)
@@ -395,24 +395,11 @@ static int meson_uart_verify_port(struct uart_port *port,
 
 static void meson_uart_release_port(struct uart_port *port)
 {
-       devm_iounmap(port->dev, port->membase);
-       port->membase = NULL;
-       devm_release_mem_region(port->dev, port->mapbase, port->mapsize);
+       /* nothing to do */
 }
 
 static int meson_uart_request_port(struct uart_port *port)
 {
-       if (!devm_request_mem_region(port->dev, port->mapbase, port->mapsize,
-                                    dev_name(port->dev))) {
-               dev_err(port->dev, "Memory region busy\n");
-               return -EBUSY;
-       }
-
-       port->membase = devm_ioremap(port->dev, port->mapbase,
-                                            port->mapsize);
-       if (!port->membase)
-               return -ENOMEM;
-
        return 0;
 }
 
@@ -733,6 +720,18 @@ static int meson_uart_probe(struct platform_device *pdev)
        if (!port)
                return -ENOMEM;
 
+       if (!devm_request_mem_region(&pdev->dev, res_mem->start,
+                                    resource_size(res_mem),
+                                    dev_name(&pdev->dev))) {
+               dev_err(&pdev->dev, "Memory region busy\n");
+               return -EBUSY;
+       }
+
+       port->membase = devm_ioremap(&pdev->dev, res_mem->start,
+                                    resource_size(res_mem));
+       if (IS_ERR(port->membase))
+               return PTR_ERR(port->membase);
+
        ret = meson_uart_probe_clocks(pdev, port);
        if (ret)
                return ret;
@@ -754,10 +753,7 @@ static int meson_uart_probe(struct platform_device *pdev)
        platform_set_drvdata(pdev, port);
 
        /* reset port before registering (and possibly registering console) */
-       if (meson_uart_request_port(port) >= 0) {
-               meson_uart_reset(port);
-               meson_uart_release_port(port);
-       }
+       meson_uart_reset(port);
 
        ret = uart_add_one_port(&meson_uart_driver, port);
        if (ret)