Commit 2ff477b7 authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Greg Kroah-Hartman
Browse files

serial: 8250_port: Introduce UART_IIR_FIFO_ENABLED_16750 



The UART_IIR_64BYTE_FIFO is always being used in conjunction with
UART_IIR_FIFO_ENABLED. Introduce a joined UART_IIR_FIFO_ENABLED_16750
definition and use it.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230911144308.4169752-1-andriy.shevchenko@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d81ffb87

drivers/tty/serial/8250/8250_port.c

+5 −6
Original line number Diff line number Diff line
@@ -1008,12 +1008,11 @@ static void autoconfig_16550a(struct uart_8250_port *up) 
			serial_out(up, UART_LCR, 0);

			serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |

				   UART_FCR7_64BYTE);

			status1 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO |

							     UART_IIR_FIFO_ENABLED);

			status1 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;

			serial_out(up, UART_FCR, 0);

			serial_out(up, UART_LCR, 0);



			if (status1 == (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED))

			if (status1 == UART_IIR_FIFO_ENABLED_16750)

				up->port.type = PORT_16550A_FSL64;

			else

				DEBUG_AUTOCONF("Motorola 8xxx DUART ");
@@ -1081,12 +1080,12 @@ static void autoconfig_16550a(struct uart_8250_port *up) 
	 */

	serial_out(up, UART_LCR, 0);

	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);

	status1 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED);

	status1 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;

	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);



	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);

	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);

	status2 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED);

	status2 = serial_in(up, UART_IIR) & UART_IIR_FIFO_ENABLED_16750;

	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);



	serial_out(up, UART_LCR, 0);
@@ -1094,7 +1093,7 @@ static void autoconfig_16550a(struct uart_8250_port *up) 
	DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);



	if (status1 == UART_IIR_FIFO_ENABLED_16550A &&

	    status2 == (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED_16550A)) {

	    status2 == UART_IIR_FIFO_ENABLED_16750) {

		up->port.type = PORT_16750;

		up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;

		return;

include/uapi/linux/serial_reg.h

+1 −0
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ 
#define  UART_IIR_FIFO_ENABLED_8250	0x00	/* 8250: no FIFO */

#define  UART_IIR_FIFO_ENABLED_16550	0x80	/* 16550: (broken/unusable) FIFO */

#define  UART_IIR_FIFO_ENABLED_16550A	0xc0	/* 16550A: FIFO enabled */

#define  UART_IIR_FIFO_ENABLED_16750	0xe0	/* 16750: 64 bytes FIFO enabled */



#define UART_FCR	2	/* Out: FIFO Control Register */

#define UART_FCR_ENABLE_FIFO	0x01 /* Enable the FIFO */