diff options
Diffstat (limited to 'drivers/serial/8250.c')
-rw-r--r-- | drivers/serial/8250.c | 152 |
1 files changed, 73 insertions, 79 deletions
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index d2bcd1f87cd..179c1f065e6 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -31,7 +31,6 @@ #include <linux/init.h> #include <linux/console.h> #include <linux/sysrq.h> -#include <linux/mca.h> #include <linux/delay.h> #include <linux/platform_device.h> #include <linux/tty.h> @@ -41,6 +40,7 @@ #include <linux/serial.h> #include <linux/serial_8250.h> #include <linux/nmi.h> +#include <linux/mutex.h> #include <asm/io.h> #include <asm/irq.h> @@ -54,6 +54,8 @@ */ static unsigned int share_irqs = SERIAL8250_SHARE_IRQS; +static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS; + /* * Debugging. */ @@ -296,7 +298,7 @@ static inline int map_8250_out_reg(struct uart_8250_port *up, int offset) #endif -static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset) +static unsigned int serial_in(struct uart_8250_port *up, int offset) { offset = map_8250_in_reg(up, offset) << up->port.regshift; @@ -321,7 +323,7 @@ static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset) } } -static _INLINE_ void +static void serial_out(struct uart_8250_port *up, int offset, int value) { offset = map_8250_out_reg(up, offset) << up->port.regshift; @@ -1131,7 +1133,7 @@ static void serial8250_enable_ms(struct uart_port *port) serial_out(up, UART_IER, up->ier); } -static _INLINE_ void +static void receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs) { struct tty_struct *tty = up->port.info->tty; @@ -1140,19 +1142,6 @@ receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs) char flag; do { - /* The following is not allowed by the tty layer and - unsafe. It should be fixed ASAP */ - if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) { - if (tty->low_latency) { - spin_unlock(&up->port.lock); - tty_flip_buffer_push(tty); - spin_lock(&up->port.lock); - } - /* - * If this failed then we will throw away the - * bytes but must do so to clear interrupts - */ - } ch = serial_inp(up, UART_RX); flag = TTY_NORMAL; up->port.icount.rx++; @@ -1217,7 +1206,7 @@ receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs) *status = lsr; } -static _INLINE_ void transmit_chars(struct uart_8250_port *up) +static void transmit_chars(struct uart_8250_port *up) { struct circ_buf *xmit = &up->port.info->xmit; int count; @@ -1255,25 +1244,24 @@ static _INLINE_ void transmit_chars(struct uart_8250_port *up) __stop_tx(up); } -static _INLINE_ void check_modem_status(struct uart_8250_port *up) +static unsigned int check_modem_status(struct uart_8250_port *up) { - int status; + unsigned int status = serial_in(up, UART_MSR); - status = serial_in(up, UART_MSR); + if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI) { + if (status & UART_MSR_TERI) + up->port.icount.rng++; + if (status & UART_MSR_DDSR) + up->port.icount.dsr++; + if (status & UART_MSR_DDCD) + uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); + if (status & UART_MSR_DCTS) + uart_handle_cts_change(&up->port, status & UART_MSR_CTS); - if ((status & UART_MSR_ANY_DELTA) == 0) - return; - - if (status & UART_MSR_TERI) - up->port.icount.rng++; - if (status & UART_MSR_DDSR) - up->port.icount.dsr++; - if (status & UART_MSR_DDCD) - uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); - if (status & UART_MSR_DCTS) - uart_handle_cts_change(&up->port, status & UART_MSR_CTS); + wake_up_interruptible(&up->port.info->delta_msr_wait); + } - wake_up_interruptible(&up->port.info->delta_msr_wait); + return status; } /* @@ -1282,7 +1270,11 @@ static _INLINE_ void check_modem_status(struct uart_8250_port *up) static inline void serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs) { - unsigned int status = serial_inp(up, UART_LSR); + unsigned int status; + + spin_lock(&up->port.lock); + + status = serial_inp(up, UART_LSR); DEBUG_INTR("status = %x...", status); @@ -1291,6 +1283,8 @@ serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs) check_modem_status(up); if (status & UART_LSR_THRE) transmit_chars(up); + + spin_unlock(&up->port.lock); } /* @@ -1326,9 +1320,7 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *r iir = serial_in(up, UART_IIR); if (!(iir & UART_IIR_NO_INT)) { - spin_lock(&up->port.lock); serial8250_handle_port(up, regs); - spin_unlock(&up->port.lock); handled = 1; @@ -1427,11 +1419,8 @@ static void serial8250_timeout(unsigned long data) unsigned int iir; iir = serial_in(up, UART_IIR); - if (!(iir & UART_IIR_NO_INT)) { - spin_lock(&up->port.lock); + if (!(iir & UART_IIR_NO_INT)) serial8250_handle_port(up, NULL); - spin_unlock(&up->port.lock); - } timeout = up->port.timeout; timeout = timeout > 6 ? (timeout / 2 - 2) : 1; @@ -1454,10 +1443,10 @@ static unsigned int serial8250_tx_empty(struct uart_port *port) static unsigned int serial8250_get_mctrl(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; - unsigned char status; + unsigned int status; unsigned int ret; - status = serial_in(up, UART_MSR); + status = check_modem_status(up); ret = 0; if (status & UART_MSR_DCD) @@ -2037,12 +2026,6 @@ static void serial8250_config_port(struct uart_port *port, int flags) int ret; /* - * Don't probe for MCA ports on non-MCA machines. - */ - if (up->port.flags & UPF_BOOT_ONLYMCA && !MCA_bus) - return; - - /* * Find the region that we can probe for. This in turn * tells us whether we can probe for the type of port. */ @@ -2118,7 +2101,7 @@ 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 +2120,7 @@ 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 +2142,7 @@ 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; @@ -2174,7 +2157,7 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev) /* * Wait for transmitter & holding register to empty */ -static inline void wait_for_xmitr(struct uart_8250_port *up) +static inline void wait_for_xmitr(struct uart_8250_port *up, int bits) { unsigned int status, tmout = 10000; @@ -2188,7 +2171,7 @@ static inline void wait_for_xmitr(struct uart_8250_port *up) if (--tmout == 0) break; udelay(1); - } while ((status & BOTH_EMPTY) != BOTH_EMPTY); + } while ((status & bits) != bits); /* Wait up to 1s for flow control if necessary */ if (up->port.flags & UPF_CONS_FLOW) { @@ -2228,7 +2211,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) * Now, do each character */ for (i = 0; i < count; i++, s++) { - wait_for_xmitr(up); + wait_for_xmitr(up, UART_LSR_THRE); /* * Send the character out. @@ -2236,7 +2219,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) */ serial_out(up, UART_TX, *s); if (*s == 10) { - wait_for_xmitr(up); + wait_for_xmitr(up, UART_LSR_THRE); serial_out(up, UART_TX, 13); } } @@ -2245,8 +2228,8 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) * Finally, wait for transmitter to become empty * and restore the IER */ - wait_for_xmitr(up); - serial_out(up, UART_IER, ier); + wait_for_xmitr(up, BOTH_EMPTY); + serial_out(up, UART_IER, ier | UART_IER_THRI); } static int serial8250_console_setup(struct console *co, char *options) @@ -2262,7 +2245,7 @@ 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) @@ -2298,11 +2281,9 @@ 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 (p->iotype == port->iotype && - p->iobase == port->iobase && - p->membase == port->membase) + if (uart_match_port(p, port)) return line; } return -ENODEV; @@ -2422,7 +2403,7 @@ 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) @@ -2466,6 +2447,7 @@ static struct platform_driver serial8250_isa_driver = { .resume = serial8250_resume, .driver = { .name = "serial8250", + .owner = THIS_MODULE, }, }; @@ -2480,7 +2462,7 @@ static struct platform_device *serial8250_isa_devs; * 16x50 serial ports to be configured at run-time, to support PCMCIA * modems and PCI multiport cards. */ -static DECLARE_MUTEX(serial_sem); +static DEFINE_MUTEX(serial_mutex); static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *port) { @@ -2489,7 +2471,7 @@ 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]; @@ -2498,7 +2480,7 @@ 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]; @@ -2507,7 +2489,7 @@ 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]; @@ -2535,7 +2517,7 @@ int serial8250_register_port(struct uart_port *port) if (port->uartclk == 0) return -EINVAL; - down(&serial_sem); + mutex_lock(&serial_mutex); uart = serial8250_find_match_or_unused(port); if (uart) { @@ -2557,7 +2539,7 @@ int serial8250_register_port(struct uart_port *port) if (ret == 0) ret = uart->port.line; } - up(&serial_sem); + mutex_unlock(&serial_mutex); return ret; } @@ -2574,7 +2556,7 @@ void serial8250_unregister_port(int line) { struct uart_8250_port *uart = &serial8250_ports[line]; - down(&serial_sem); + mutex_lock(&serial_mutex); uart_remove_one_port(&serial8250_reg, &uart->port); if (serial8250_isa_devs) { uart->port.flags &= ~UPF_BOOT_AUTOCONF; @@ -2584,7 +2566,7 @@ void serial8250_unregister_port(int line) } else { uart->port.dev = NULL; } - up(&serial_sem); + mutex_unlock(&serial_mutex); } EXPORT_SYMBOL(serial8250_unregister_port); @@ -2592,8 +2574,11 @@ 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++) @@ -2603,21 +2588,27 @@ static int __init serial8250_init(void) if (ret) goto out; - serial8250_isa_devs = platform_device_register_simple("serial8250", - PLAT8250_DEV_LEGACY, NULL, 0); - if (IS_ERR(serial8250_isa_devs)) { - ret = PTR_ERR(serial8250_isa_devs); - goto unreg; + serial8250_isa_devs = platform_device_alloc("serial8250", + PLAT8250_DEV_LEGACY); + if (!serial8250_isa_devs) { + ret = -ENOMEM; + goto unreg_uart_drv; } + ret = platform_device_add(serial8250_isa_devs); + if (ret) + goto put_dev; + serial8250_register_ports(&serial8250_reg, &serial8250_isa_devs->dev); ret = platform_driver_register(&serial8250_isa_driver); if (ret == 0) goto out; - platform_device_unregister(serial8250_isa_devs); - unreg: + platform_device_del(serial8250_isa_devs); + put_dev: + platform_device_put(serial8250_isa_devs); + unreg_uart_drv: uart_unregister_driver(&serial8250_reg); out: return ret; @@ -2653,6 +2644,9 @@ 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"); |