tty/serial: Add support for Altera serial port

Add support for Altera 8250/16550 compatible serial port.
Signed-off-by: Ley Foon Tan <lftan@altera.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/tty/serial/of-serial.txt

@@ -11,6 +11,9 @@ Required properties:
 	- "nvidia,tegra20-uart"
 	- "nxp,lpc3220-uart"
 	- "ibm,qpace-nwp-serial"
+	- "altr,16550-FIFO32"
+	- "altr,16550-FIFO64"
+	- "altr,16550-FIFO128"
 	- "serial" if the port type is unknown.
 - reg : offset and length of the register set for the device.
 - interrupts : should contain uart interrupt.

drivers/tty/serial/8250/8250.c

@@ -301,7 +301,28 @@ static const struct serial8250_config uart_config[] = {
 	},
 	[PORT_8250_CIR] = {
 		.name		= "CIR port"
-	}
+	},
+	[PORT_ALTR_16550_F32] = {
+		.name		= "Altera 16550 FIFO32",
+		.fifo_size	= 32,
+		.tx_loadsz	= 32,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_ALTR_16550_F64] = {
+		.name		= "Altera 16550 FIFO64",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_ALTR_16550_F128] = {
+		.name		= "Altera 16550 FIFO128",
+		.fifo_size	= 128,
+		.tx_loadsz	= 128,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
 };
 
 /* Uart divisor latch read */

drivers/tty/serial/of_serial.c

@@ -241,6 +241,12 @@ static struct of_device_id of_platform_serial_table[] = {
 	{ .compatible = "ns16850",  .data = (void *)PORT_16850, },
 	{ .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
 	{ .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
+	{ .compatible = "altr,16550-FIFO32",
+		.data = (void *)PORT_ALTR_16550_F32, },
+	{ .compatible = "altr,16550-FIFO64",
+		.data = (void *)PORT_ALTR_16550_F64, },
+	{ .compatible = "altr,16550-FIFO128",
+		.data = (void *)PORT_ALTR_16550_F128, },
 #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
 	{ .compatible = "ibm,qpace-nwp-serial",
 		.data = (void *)PORT_NWPSERIAL, },

include/uapi/linux/serial_core.h

@@ -51,7 +51,10 @@
 #define PORT_8250_CIR	23	/* CIR infrared port, has its own driver */
 #define PORT_XR17V35X	24	/* Exar XR17V35x UARTs */
 #define PORT_BRCM_TRUMANAGE	25
-#define PORT_MAX_8250	25	/* max port ID */
+#define PORT_ALTR_16550_F32 26	/* Altera 16550 UART with 32 FIFOs */
+#define PORT_ALTR_16550_F64 27	/* Altera 16550 UART with 64 FIFOs */
+#define PORT_ALTR_16550_F128 28 /* Altera 16550 UART with 128 FIFOs */
+#define PORT_MAX_8250	28	/* max port ID */
 
 /*
  * ARM specific type numbers.  These are not currently guaranteed