From: David Daney <ddaney@xxxxxxxxxxxxxxxxxx> Add flag value UPF_FIXED_TYPE which specifies that the UART type is known and should not be probed. For this case the UARTs properties are just copied out of the uart_config entry. Signed-off-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx> --- drivers/serial/8250.c | 8 ++++++++ drivers/serial/serial_core.c | 7 +++++-- include/linux/serial_core.h | 2 ++ 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 7b7850b..e26c090 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -3010,6 +3010,14 @@ int serial8250_register_port(struct uart_port *port) uart->port.private_data = port->private_data; if (port->dev) uart->port.dev = port->dev; + + if (port->flags & UPF_FIXED_TYPE) { + uart->port.type = port->type; + uart->port.fifosize = uart_config[port->type].fifo_size; + uart->capabilities = uart_config[port->type].flags; + uart->tx_loadsz = uart_config[port->type].tx_loadsz; + } + set_io_fns_from_upio(&uart->port); /* Possibly override default I/O functions. */ if (port->serial_in_fn) diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 6bdf336..1f6685e 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -2198,11 +2198,14 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, * Now do the auto configuration stuff. Note that config_port * is expected to claim the resources and map the port for us. */ - flags = UART_CONFIG_TYPE; + flags = 0; if (port->flags & UPF_AUTO_IRQ) flags |= UART_CONFIG_IRQ; if (port->flags & UPF_BOOT_AUTOCONF) { - port->type = PORT_UNKNOWN; + if (!(port->flags & UPF_FIXED_TYPE)) { + port->type = PORT_UNKNOWN; + flags |= UART_CONFIG_TYPE; + } port->ops->config_port(port, flags); } diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 40509b0..54e0dce 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -290,6 +290,8 @@ struct uart_port { #define UPF_MAGIC_MULTIPLIER ((__force upf_t) (1 << 16)) #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) #define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) +/* The exact UART type is known and should not be probed. */ +#define UPF_FIXED_TYPE ((__force upf_t) (1 << 27)) #define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) #define UPF_FIXED_PORT ((__force upf_t) (1 << 29)) #define UPF_DEAD ((__force upf_t) (1 << 30)) -- 1.5.5.1