[SERIAL] Make the number of UARTs registered configurable.

Also add a nr_uarts module option to the 8250 code to override
this, up to a maximum of CONFIG_SERIAL_8250_NR_UARTS

This should appease people who complain about a proliferation
of /dev/ttyS & /sysfs nodes whilst at the same time allowing
a single kernel image to support the rarer occasions of
lots of devices.

Signed-off-by: Dave Jones <davej@redhat.com>
This commit is contained in:
Dave Jones 2006-01-07 23:18:19 +00:00 committed by Russell King
parent f61051cd2f
commit a61c2d78ce
3 changed files with 30 additions and 10 deletions

View File

@ -998,6 +998,8 @@ running once the system is up.
nowb [ARM]
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
opl3= [HW,OSS]
Format: <io>

View File

@ -54,6 +54,8 @@
*/
static unsigned int share_irqs = SERIAL8250_SHARE_IRQS;
static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS;
/*
* Debugging.
*/
@ -2118,7 +2120,7 @@ static void __init serial8250_isa_init_ports(void)
return;
first = 0;
for (i = 0; i < UART_NR; i++) {
for (i = 0; i < nr_uarts; i++) {
struct uart_8250_port *up = &serial8250_ports[i];
up->port.line = i;
@ -2137,7 +2139,7 @@ static void __init serial8250_isa_init_ports(void)
}
for (i = 0, up = serial8250_ports;
i < ARRAY_SIZE(old_serial_port) && i < UART_NR;
i < ARRAY_SIZE(old_serial_port) && i < nr_uarts;
i++, up++) {
up->port.iobase = old_serial_port[i].port;
up->port.irq = irq_canonicalize(old_serial_port[i].irq);
@ -2159,7 +2161,7 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
serial8250_isa_init_ports();
for (i = 0; i < UART_NR; i++) {
for (i = 0; i < nr_uarts; i++) {
struct uart_8250_port *up = &serial8250_ports[i];
up->port.dev = dev;
@ -2262,7 +2264,7 @@ static int serial8250_console_setup(struct console *co, char *options)
* if so, search for the first available port that does have
* console support.
*/
if (co->index >= UART_NR)
if (co->index >= nr_uarts)
co->index = 0;
port = &serial8250_ports[co->index].port;
if (!port->iobase && !port->membase)
@ -2298,7 +2300,7 @@ static int __init find_port(struct uart_port *p)
int line;
struct uart_port *port;
for (line = 0; line < UART_NR; line++) {
for (line = 0; line < nr_uarts; line++) {
port = &serial8250_ports[line].port;
if (uart_match_port(p, port))
return line;
@ -2420,7 +2422,7 @@ static int __devexit serial8250_remove(struct platform_device *dev)
{
int i;
for (i = 0; i < UART_NR; i++) {
for (i = 0; i < nr_uarts; i++) {
struct uart_8250_port *up = &serial8250_ports[i];
if (up->port.dev == &dev->dev)
@ -2487,7 +2489,7 @@ static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *
/*
* First, find a port entry which matches.
*/
for (i = 0; i < UART_NR; i++)
for (i = 0; i < nr_uarts; i++)
if (uart_match_port(&serial8250_ports[i].port, port))
return &serial8250_ports[i];
@ -2496,7 +2498,7 @@ static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *
* free entry. We look for one which hasn't been previously
* used (indicated by zero iobase).
*/
for (i = 0; i < UART_NR; i++)
for (i = 0; i < nr_uarts; i++)
if (serial8250_ports[i].port.type == PORT_UNKNOWN &&
serial8250_ports[i].port.iobase == 0)
return &serial8250_ports[i];
@ -2505,7 +2507,7 @@ static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *
* That also failed. Last resort is to find any entry which
* doesn't have a real port associated with it.
*/
for (i = 0; i < UART_NR; i++)
for (i = 0; i < nr_uarts; i++)
if (serial8250_ports[i].port.type == PORT_UNKNOWN)
return &serial8250_ports[i];
@ -2590,8 +2592,11 @@ static int __init serial8250_init(void)
{
int ret, i;
if (nr_uarts > UART_NR)
nr_uarts = UART_NR;
printk(KERN_INFO "Serial: 8250/16550 driver $Revision: 1.90 $ "
"%d ports, IRQ sharing %sabled\n", (int) UART_NR,
"%d ports, IRQ sharing %sabled\n", nr_uarts,
share_irqs ? "en" : "dis");
for (i = 0; i < NR_IRQS; i++)
@ -2651,6 +2656,9 @@ module_param(share_irqs, uint, 0644);
MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices"
" (unsafe)");
module_param(nr_uarts, uint, 0644);
MODULE_PARM_DESC(nr_uarts, "Maximum number of UARTs supported. (1-" __MODULE_STRING(CONFIG_SERIAL_8250_NR_UARTS) ")");
#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");

View File

@ -95,6 +95,16 @@ config SERIAL_8250_NR_UARTS
PCI enumeration and any ports that may be added at run-time
via hot-plug, or any ISA multi-port serial cards.
config SERIAL_8250_RUNTIME_UARTS
int "Number of 8250/16550 serial ports to register at runtime"
depends on SERIAL_8250
default "4"
help
Set this to the maximum number of serial ports you want
the kernel to register at boot time. This can be overriden
with the module parameter "nr_uarts", or boot-time parameter
8250.nr_uarts
config SERIAL_8250_EXTENDED
bool "Extended 8250/16550 serial driver options"
depends on SERIAL_8250