serial: 8250_bcm7271: Switch to use uart_read_port_properties()

Since we have now a common helper to read port properties
use it instead of sparse home grown solution.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240304123035.758700-7-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_bcm7271.c

@@ -935,17 +935,14 @@ static void brcmuart_init_debugfs(struct brcmuart_priv *priv,
 static int brcmuart_probe(struct platform_device *pdev)
 {
 	struct resource *regs;
-	struct device_node *np = pdev->dev.of_node;
 	const struct of_device_id *of_id = NULL;
 	struct uart_8250_port *new_port;
 	struct device *dev = &pdev->dev;
 	struct brcmuart_priv *priv;
 	struct clk *baud_mux_clk;
 	struct uart_8250_port up;
-	int irq;
 	void __iomem *membase = NULL;
 	resource_size_t mapbase = 0;
-	u32 clk_rate = 0;
 	int ret;
 	int x;
 	int dma_irq;
@@ -953,15 +950,12 @@ static int brcmuart_probe(struct platform_device *pdev)
 		"uart", "dma_rx", "dma_tx", "dma_intr2", "dma_arb"
 	};
 
-	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
-		return irq;
 	priv = devm_kzalloc(dev, sizeof(struct brcmuart_priv),
 			GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
-	of_id = of_match_node(brcmuart_dt_ids, np);
+	of_id = of_match_node(brcmuart_dt_ids, dev->of_node);
 	if (!of_id || !of_id->data)
 		priv->rate_table = brcmstb_rate_table;
 	else
@@ -1011,7 +1005,23 @@ static int brcmuart_probe(struct platform_device *pdev)
 		}
 	}
 
-	of_property_read_u32(np, "clock-frequency", &clk_rate);
+	dev_dbg(dev, "DMA is %senabled\n", priv->dma_enabled ? "" : "not ");
+
+	memset(&up, 0, sizeof(up));
+	up.port.type = PORT_BCM7271;
+	up.port.dev = dev;
+	up.port.mapbase = mapbase;
+	up.port.membase = membase;
+	up.port.handle_irq = brcmuart_handle_irq;
+	up.port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_FIXED_TYPE;
+	up.port.private_data = priv;
+
+	ret = uart_read_port_properties(&up.port);
+	if (ret)
+		goto release_dma;
+
+	up.port.regshift = 2;
+	up.port.iotype = device_is_big_endian(dev) ? UPIO_MEM32BE : UPIO_MEM32;
 
 	/* See if a Baud clock has been specified */
 	baud_mux_clk = devm_clk_get_optional_enabled(dev, "sw_baud");
@@ -1023,39 +1033,11 @@ static int brcmuart_probe(struct platform_device *pdev)
 
 		priv->baud_mux_clk = baud_mux_clk;
 		init_real_clk_rates(dev, priv);
-		clk_rate = priv->default_mux_rate;
+		up.port.uartclk = priv->default_mux_rate;
 	} else {
 		dev_dbg(dev, "BAUD MUX clock not specified\n");
 	}
 
-	if (clk_rate == 0) {
-		ret = dev_err_probe(dev, -EINVAL, "clock-frequency or clk not defined\n");
-		goto release_dma;
-	}
-
-	dev_dbg(dev, "DMA is %senabled\n", priv->dma_enabled ? "" : "not ");
-
-	memset(&up, 0, sizeof(up));
-	up.port.type = PORT_BCM7271;
-	up.port.uartclk = clk_rate;
-	up.port.dev = dev;
-	up.port.mapbase = mapbase;
-	up.port.membase = membase;
-	up.port.irq = irq;
-	up.port.handle_irq = brcmuart_handle_irq;
-	up.port.regshift = 2;
-	up.port.iotype = of_device_is_big_endian(np) ?
-		UPIO_MEM32BE : UPIO_MEM32;
-	up.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF
-		| UPF_FIXED_PORT | UPF_FIXED_TYPE;
-	up.port.dev = dev;
-	up.port.private_data = priv;
-
-	/* Check for a fixed line number */
-	ret = of_alias_get_id(np, "serial");
-	if (ret >= 0)
-		up.port.line = ret;
-
 	/* setup HR timer */
 	hrtimer_init(&priv->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 	priv->hrt.function = brcmuart_hrtimer_func;