From: Chuck Ebbert <cebbert@xxxxxxxxxx> Allow users to force skipping the TXEN test at init time. Applies to all serial ports. Intended for debugging only. There is a blacklist for devices where we need to skip the test but the list is not complete. This lets users force skipping the test so we can determine if they need to be added to the list. Some HP machines with weird serial consoles have this problem and there may be more. Signed-off-by: Chuck Ebbert <cebbert@xxxxxxxxxx> Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/serial/8250.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff -puN drivers/serial/8250.c~serial-add-parameter-to-force-skipping-the-test-for-the-txen-bug drivers/serial/8250.c --- a/drivers/serial/8250.c~serial-add-parameter-to-force-skipping-the-test-for-the-txen-bug +++ a/drivers/serial/8250.c @@ -64,6 +64,8 @@ static int serial_index(struct uart_port return (serial8250_reg.minor - 64) + port->line; } +static unsigned int skip_txen_test; /* force skip of txen test at init time */ + /* * Debugging. */ @@ -2108,7 +2110,7 @@ static int serial8250_startup(struct uar is variable. So, let's just don't test if we receive TX irq. This way, we'll never enable UART_BUG_TXEN. */ - if (up->port.flags & UPF_NO_TXEN_TEST) + if (skip_txen_test || up->port.flags & UPF_NO_TXEN_TEST) goto dont_test_tx_en; /* @@ -3248,6 +3250,9 @@ MODULE_PARM_DESC(share_irqs, "Share IRQs module_param(nr_uarts, uint, 0644); MODULE_PARM_DESC(nr_uarts, "Maximum number of UARTs supported. (1-" __MODULE_STRING(CONFIG_SERIAL_8250_NR_UARTS) ")"); +module_param(skip_txen_test, uint, 0644); +MODULE_PARM_DESC(skip_txen_test, "Skip checking for the TXEN bug at init time"); + #ifdef CONFIG_SERIAL_8250_RSA module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444); MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA"); _ -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
