[PATCH v1] serial: qcom-geni: Remove alias dependency from qcom serial driver

[Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx>]

Remove the dependency on aliases in the device tree configuration for the
qcom serial driver. Currently, the absence of an alias results in an
invalid line number, causing the driver probe to fail for geni serial.

To prevent probe failures, implement logic to dynamically assign line
numbers if an alias is not present in the device tree for non-console
ports.

Signed-off-by: Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx>
---
 drivers/tty/serial/qcom_geni_serial.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index a80ce7aaf309..2457f39dfc84 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -98,6 +98,8 @@
 
 #define DMA_RX_BUF_SIZE		2048
 
+static DEFINE_IDR(port_idr);
+
 struct qcom_geni_device_data {
 	bool console;
 	enum geni_se_xfer_mode mode;
@@ -253,10 +255,25 @@ static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
 	struct qcom_geni_serial_port *port;
 	int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
 
-	if (line < 0 || line >= nr_ports)
-		return ERR_PTR(-ENXIO);
+	if (console) {
+		if (line < 0 || line >= nr_ports)
+			return ERR_PTR(-ENXIO);
+
+		port = &qcom_geni_console_port;
+	} else {
+		int max_alias_num = of_alias_get_highest_id("serial");
+
+		if (line < 0 || line >= nr_ports)
+			line = idr_alloc(&port_idr, (void *)port, max_alias_num + 1, nr_ports,
+					 GFP_KERNEL);
+		else
+			line = idr_alloc(&port_idr, (void *)port, line, nr_ports, GFP_KERNEL);
+
+		if (line < 0)
+			return ERR_PTR(-ENXIO);
 
-	port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
+		port = &qcom_geni_uart_ports[line];
+	}
 	return port;
 }
 
@@ -1761,6 +1778,7 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 						port->wakeup_irq);
 		if (ret) {
 			device_init_wakeup(&pdev->dev, false);
+			idr_remove(&port_idr, uport->line);
 			uart_remove_one_port(drv, uport);
 			return ret;
 		}
@@ -1772,10 +1790,12 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 static void qcom_geni_serial_remove(struct platform_device *pdev)
 {
 	struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
+	struct uart_port *uport = &port->uport;
 	struct uart_driver *drv = port->private_data.drv;
 
 	dev_pm_clear_wake_irq(&pdev->dev);
 	device_init_wakeup(&pdev->dev, false);
+	idr_remove(&port_idr, uport->line);
 	uart_remove_one_port(drv, &port->uport);
 }
 
-- 
2.34.1