serial: switch uart_port::iotype to enum uart_iotype

The inline-defined constants look weird. Instead, define a proper enum
for them and type uart_port::iotype as that enum. This allows for proper
checking in switch-case labels (somewhere, a default or UPIO_UNKNOWN
label needs to be added/handled).

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250425111315.1036184-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

8 files changed, 22 insertions, 7 deletions

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 5a56f853cf6d..68994a964321 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -461,7 +461,7 @@ static int univ8250_console_match(struct console *co, char *name, int idx,
 				  char *options)
 {
 	char match[] = "uart";	/* 8250-specific earlycon name */
-	unsigned char iotype;
+	enum uart_iotype iotype;
 	resource_size_t addr;
 	int i;
 
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index 842422921765..dc0371857ecb 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -77,6 +77,8 @@ static void serial8250_early_out(struct uart_port *port, int offset, int value)
 		outb(value, port->iobase + offset);
 		break;
 #endif
+	default:
+		break;
 	}
 }
 
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 8ac452cea36c..8d9bb91d4bae 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2993,6 +2993,8 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
 		if (!request_region(port->iobase, size, "serial"))
 			return -EBUSY;
 		return 0;
+	case UPIO_UNKNOWN:
+		break;
 	}
 
 	return 0;
@@ -3025,6 +3027,8 @@ static void serial8250_release_std_resource(struct uart_8250_port *up)
 	case UPIO_PORT:
 		release_region(port->iobase, size);
 		break;
+	case UPIO_UNKNOWN:
+		break;
 	}
 }
 
diff --git a/drivers/tty/serial/8250/8250_rsa.c b/drivers/tty/serial/8250/8250_rsa.c
index 82f2593b4c59..4c8b9671bd41 100644
--- a/drivers/tty/serial/8250/8250_rsa.c
+++ b/drivers/tty/serial/8250/8250_rsa.c
@@ -43,6 +43,8 @@ static void rsa8250_release_resource(struct uart_8250_port *up)
 	case UPIO_PORT:
 		release_region(port->iobase + offset, size);
 		break;
+	default:
+		break;
 	}
 }
 
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 11d65097578c..421ac22555df 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2476,7 +2476,7 @@ static int pl011_console_setup(struct console *co, char *options)
 static int pl011_console_match(struct console *co, char *name, int idx,
 			       char *options)
 {
-	unsigned char iotype;
+	enum uart_iotype iotype;
 	resource_size_t addr;
 	int i;
 
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index fe5aed99d55a..dff6a6c57b5f 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -403,6 +403,8 @@ static inline void lpuart32_write(struct uart_port *port, u32 val,
 	case UPIO_MEM32BE:
 		iowrite32be(val, port->membase + off);
 		break;
+	default:
+		break;
 	}
 }
 
@@ -563,8 +565,9 @@ static dma_addr_t lpuart_dma_datareg_addr(struct lpuart_port *sport)
 		return sport->port.mapbase + UARTDATA;
 	case UPIO_MEM32BE:
 		return sport->port.mapbase + UARTDATA + sizeof(u32) - 1;
+	default:
+		return sport->port.mapbase + UARTDR;
 	}
-	return sport->port.mapbase + UARTDR;
 }
 
 static int lpuart_dma_tx_request(struct uart_port *port)
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 210fff7164c1..73e2866febc1 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -190,6 +190,8 @@ static void wr_reg(const struct uart_port *port, u32 reg, u32 val)
 	case UPIO_MEM32:
 		writel_relaxed(val, portaddr(port, reg));
 		break;
+	default:
+		break;
 	}
 }
 
@@ -2713,6 +2715,8 @@ static void wr_reg_barrier(const struct uart_port *port, u32 reg, u32 val)
 	case UPIO_MEM32:
 		writel(val, portaddr(port, reg));
 		break;
+	default:
+		break;
 	}
 }
 
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 88669972d9a0..5bc145643385 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2178,8 +2178,8 @@ uart_get_console(struct uart_port *ports, int nr, struct console *co)
  *
  * Returns: 0 on success or -%EINVAL on failure
  */
-int uart_parse_earlycon(char *p, unsigned char *iotype, resource_size_t *addr,
-			char **options)
+int uart_parse_earlycon(char *p, enum uart_iotype *iotype,
+			resource_size_t *addr, char **options)
 {
 	if (strncmp(p, "mmio,", 5) == 0) {
 		*iotype = UPIO_MEM;
@@ -3289,9 +3289,9 @@ bool uart_match_port(const struct uart_port *port1,
 	case UPIO_AU:
 	case UPIO_TSI:
 		return port1->mapbase == port2->mapbase;
+	default:
+		return false;
 	}
-
-	return false;
 }
 EXPORT_SYMBOL(uart_match_port);