serial: qcom-geni: Remove alias dependency from qcom serial driver

The absence of an alias in the device tree results in an invalid line
number, causing the driver probe to fail for GENI serial.

To prevent probe failures, 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@quicinc.com>
Link: https://lore.kernel.org/r/20250327070711.2585887-1-quic_vdadhani@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index a80ce7aaf309d1754cbae6469259291b79854c2a..0293b6210aa67678b7b688fc64b82cd30a27600e 100644 (file)
--- 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_IDA(port_ida);
+
 struct qcom_geni_device_data {
        bool console;
        enum geni_se_xfer_mode mode;
@@ -253,10 +255,24 @@ 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 = ida_alloc_range(&port_ida, max_alias_num + 1, nr_ports, GFP_KERNEL);
+               else
+                       line = ida_alloc_range(&port_ida, 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 +1777,7 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
                                                port->wakeup_irq);
                if (ret) {
                        device_init_wakeup(&pdev->dev, false);
+                       ida_free(&port_ida, uport->line);
                        uart_remove_one_port(drv, uport);
                        return ret;
                }
@@ -1772,10 +1789,12 @@ 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);
+       ida_free(&port_ida, uport->line);
        uart_remove_one_port(drv, &port->uport);
 }