From f61051cd2fc58546f28c226933942d4360810ffb Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 7 Jan 2006 23:11:23 +0000 Subject: [SERIAL] Fix clocal wakeup problem Jim Alexander reported a problem where "if one calls open() in blocking mode with CLOCAL off, the 8250.c driver under the 2.6 kernel (or at least 2.6.8 and 2.6.10) does not wake up the blocked process when DCD is asserted." Fix this by enabling modem status interrupts immediately before we read the carrier detect status. Thanks to Jim for reporting the problem and testing the fix. Signed-off-by: Russell King --- drivers/serial/serial_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 34c576dfad8d..9589509fc5bd 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -1440,6 +1440,7 @@ uart_block_til_ready(struct file *filp, struct uart_state *state) * modem is ready for us. */ spin_lock_irq(&port->lock); + port->ops->enable_ms(port); mctrl = port->ops->get_mctrl(port); spin_unlock_irq(&port->lock); if (mctrl & TIOCM_CAR) -- cgit v1.2.3-59-g8ed1b From a61c2d78ce61e67baf27c43f6721db87a27ac762 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Sat, 7 Jan 2006 23:18:19 +0000 Subject: [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 --- Documentation/kernel-parameters.txt | 2 ++ drivers/serial/8250.c | 28 ++++++++++++++++++---------- drivers/serial/Kconfig | 10 ++++++++++ 3 files changed, 30 insertions(+), 10 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index acb010bb087b..0dc848bf0b56 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -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: diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 1891cf5bdeef..e8454611cb65 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -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"); diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 812bae62c8ec..3fd5b999fdac 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -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 -- cgit v1.2.3-59-g8ed1b