serial: 8250_dw: Move device tree code to separate function

Trivial cleanup. This makes it easier to add different
methods to enumerate the device, for example ACPI 5.0
enumeration.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index e1749012e8e388c4450701f8fa3d643966541bc6..d96e02e25be4300997169300eeb0ee40b79d33dd 100644 (file)
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -87,25 +87,51 @@ static int dw8250_handle_irq(struct uart_port *p)
        return 0;
 }
 
+static int dw8250_probe_of(struct uart_port *p)
+{
+       struct device_node      *np = p->dev->of_node;
+       u32                     val;
+
+       if (!of_property_read_u32(np, "reg-io-width", &val)) {
+               switch (val) {
+               case 1:
+                       break;
+               case 4:
+                       p->iotype = UPIO_MEM32;
+                       p->serial_in = dw8250_serial_in32;
+                       p->serial_out = dw8250_serial_out32;
+                       break;
+               default:
+                       dev_err(p->dev, "unsupported reg-io-width (%u)\n", val);
+                       return -EINVAL;
+               }
+       }
+
+       if (!of_property_read_u32(np, "reg-shift", &val))
+               p->regshift = val;
+
+       if (of_property_read_u32(np, "clock-frequency", &val)) {
+               dev_err(p->dev, "no clock-frequency property set\n");
+               return -EINVAL;
+       }
+       p->uartclk = val;
+
+       return 0;
+}
+
 static int dw8250_probe(struct platform_device *pdev)
 {
        struct uart_8250_port uart = {};
        struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-       struct device_node *np = pdev->dev.of_node;
-       u32 val;
        struct dw8250_data *data;
+       int err;
 
        if (!regs || !irq) {
                dev_err(&pdev->dev, "no registers/irq defined\n");
                return -EINVAL;
        }
 
-       data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
-       if (!data)
-               return -ENOMEM;
-       uart.port.private_data = data;
-
        spin_lock_init(&uart.port.lock);
        uart.port.mapbase = regs->start;
        uart.port.irq = irq->start;
@@ -121,30 +147,20 @@ static int dw8250_probe(struct platform_device *pdev)
        uart.port.iotype = UPIO_MEM;
        uart.port.serial_in = dw8250_serial_in;
        uart.port.serial_out = dw8250_serial_out;
-       if (!of_property_read_u32(np, "reg-io-width", &val)) {
-               switch (val) {
-               case 1:
-                       break;
-               case 4:
-                       uart.port.iotype = UPIO_MEM32;
-                       uart.port.serial_in = dw8250_serial_in32;
-                       uart.port.serial_out = dw8250_serial_out32;
-                       break;
-               default:
-                       dev_err(&pdev->dev, "unsupported reg-io-width (%u)\n",
-                               val);
-                       return -EINVAL;
-               }
+
+       if (pdev->dev.of_node) {
+               err = dw8250_probe_of(&uart.port);
+               if (err)
+                       return err;
+       } else {
+               return -ENODEV;
        }
 
-       if (!of_property_read_u32(np, "reg-shift", &val))
-               uart.port.regshift = val;
+       data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
 
-       if (of_property_read_u32(np, "clock-frequency", &val)) {
-               dev_err(&pdev->dev, "no clock-frequency property set\n");
-               return -EINVAL;
-       }
-       uart.port.uartclk = val;
+       uart.port.private_data = data;
 
        data->line = serial8250_register_8250_port(&uart);
        if (data->line < 0)
@@ -187,17 +203,17 @@ static int dw8250_resume(struct platform_device *pdev)
 #define dw8250_resume NULL
 #endif /* CONFIG_PM */
 
-static const struct of_device_id dw8250_match[] = {
+static const struct of_device_id dw8250_of_match[] = {
        { .compatible = "snps,dw-apb-uart" },
        { /* Sentinel */ }
 };
-MODULE_DEVICE_TABLE(of, dw8250_match);
+MODULE_DEVICE_TABLE(of, dw8250_of_match);
 
 static struct platform_driver dw8250_platform_driver = {
        .driver = {
                .name           = "dw-apb-uart",
                .owner          = THIS_MODULE,
-               .of_match_table = dw8250_match,
+               .of_match_table = dw8250_of_match,
        },
        .probe                  = dw8250_probe,
        .remove                 = dw8250_remove,