diff options
| author | Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> | 2022-11-25 16:05:08 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-19 17:01:20 +0300 |
| commit | afd216ca17b1fd24f6b73a1490752c22ab42598c (patch) | |
| tree | 838c3b2b84b9700b87eea7109c82b725c446d93c | |
| parent | 3398cc4f2b1592148a2ebabc5a2df3e303d4e77c (diff) | |
| download | linux-afd216ca17b1fd24f6b73a1490752c22ab42598c.tar.xz | |
serial: 8250: Define IIR 64 byte bit & cleanup related code
16750 indicates 64 bytes FIFO with a IIR bit. Add define for it and
make related code more obvious.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221125130509.8482-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 14 | ||||
| -rw-r--r-- | include/uapi/linux/serial_reg.h | 1 |
2 files changed, 10 insertions, 5 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index a47ce3e974a2..33be7aad11ef 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1050,11 +1050,12 @@ 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) >> 5; + status1 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO | + UART_IIR_FIFO_ENABLED); serial_out(up, UART_FCR, 0); serial_out(up, UART_LCR, 0); - if (status1 == 7) + if (status1 == (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED)) up->port.type = PORT_16550A_FSL64; else DEBUG_AUTOCONF("Motorola 8xxx DUART "); @@ -1122,17 +1123,20 @@ 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) >> 5; + status1 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED); 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) >> 5; + status2 = serial_in(up, UART_IIR) & (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED); serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); + serial_out(up, UART_LCR, 0); DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2); - if (status1 == 6 && status2 == 7) { + if (status1 == UART_IIR_FIFO_ENABLED_16550A && + status2 == (UART_IIR_64BYTE_FIFO | UART_IIR_FIFO_ENABLED_16550A)) { up->port.type = PORT_16750; up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP; return; diff --git a/include/uapi/linux/serial_reg.h b/include/uapi/linux/serial_reg.h index 19aef5b0b049..08b3527e1b93 100644 --- a/include/uapi/linux/serial_reg.h +++ b/include/uapi/linux/serial_reg.h @@ -44,6 +44,7 @@ #define UART_IIR_RX_TIMEOUT 0x0c /* OMAP RX Timeout interrupt */ #define UART_IIR_XOFF 0x10 /* OMAP XOFF/Special Character */ #define UART_IIR_CTS_RTS_DSR 0x20 /* OMAP CTS/RTS/DSR Change */ +#define UART_IIR_64BYTE_FIFO 0x20 /* 16750 64 bytes FIFO */ #define UART_IIR_FIFO_ENABLED 0xc0 /* FIFOs enabled / port type identification */ #define UART_IIR_FIFO_ENABLED_8250 0x00 /* 8250: no FIFO */ #define UART_IIR_FIFO_ENABLED_16550 0x80 /* 16550: (broken/unusable) FIFO */ |