]> git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/commitdiff
Merge 3.9-rc5 into tty-next
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 1 Apr 2013 19:01:10 +0000 (12:01 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 1 Apr 2013 19:01:10 +0000 (12:01 -0700)
We need the fixes here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1  2 
drivers/tty/serial/8250/8250_core.c
drivers/tty/serial/xilinx_uartps.c
drivers/usb/class/cdc-acm.c
drivers/usb/serial/io_edgeport.c
drivers/usb/serial/mos7840.c
drivers/usb/serial/quatech2.c
drivers/usb/serial/ti_usb_3410_5052.c
drivers/usb/serial/usb-serial.c

index 0000000000000000000000000000000000000000,35f9c96aada9c9f6d31238accab3ddd7887ed2fb..46528d57be72b710513a65ad2494ae839774981a
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,3450 +1,3454 @@@
 -      for (i = 0; i < nr_uarts; i++) {
+ /*
+  *  Driver for 8250/16550-type serial ports
+  *
+  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+  *
+  *  Copyright (C) 2001 Russell King.
+  *
+  * This program is free software; you can redistribute it and/or modify
+  * it under the terms of the GNU General Public License as published by
+  * the Free Software Foundation; either version 2 of the License, or
+  * (at your option) any later version.
+  *
+  * A note about mapbase / membase
+  *
+  *  mapbase is the physical address of the IO port.
+  *  membase is an 'ioremapped' cookie.
+  */
+ #if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+ #define SUPPORT_SYSRQ
+ #endif
+ #include <linux/module.h>
+ #include <linux/moduleparam.h>
+ #include <linux/ioport.h>
+ #include <linux/init.h>
+ #include <linux/console.h>
+ #include <linux/sysrq.h>
+ #include <linux/delay.h>
+ #include <linux/platform_device.h>
+ #include <linux/tty.h>
+ #include <linux/ratelimit.h>
+ #include <linux/tty_flip.h>
+ #include <linux/serial_reg.h>
+ #include <linux/serial_core.h>
+ #include <linux/serial.h>
+ #include <linux/serial_8250.h>
+ #include <linux/nmi.h>
+ #include <linux/mutex.h>
+ #include <linux/slab.h>
+ #ifdef CONFIG_SPARC
+ #include <linux/sunserialcore.h>
+ #endif
+ #include <asm/io.h>
+ #include <asm/irq.h>
+ #include "8250.h"
+ /*
+  * Configuration:
+  *   share_irqs - whether we pass IRQF_SHARED to request_irq().  This option
+  *                is unsafe when used on edge-triggered interrupts.
+  */
+ static unsigned int share_irqs = SERIAL8250_SHARE_IRQS;
+ static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS;
+ static struct uart_driver serial8250_reg;
+ static int serial_index(struct uart_port *port)
+ {
+       return (serial8250_reg.minor - 64) + port->line;
+ }
+ static unsigned int skip_txen_test; /* force skip of txen test at init time */
+ /*
+  * Debugging.
+  */
+ #if 0
+ #define DEBUG_AUTOCONF(fmt...)        printk(fmt)
+ #else
+ #define DEBUG_AUTOCONF(fmt...)        do { } while (0)
+ #endif
+ #if 0
+ #define DEBUG_INTR(fmt...)    printk(fmt)
+ #else
+ #define DEBUG_INTR(fmt...)    do { } while (0)
+ #endif
+ #define PASS_LIMIT    512
+ #define BOTH_EMPTY    (UART_LSR_TEMT | UART_LSR_THRE)
+ #ifdef CONFIG_SERIAL_8250_DETECT_IRQ
+ #define CONFIG_SERIAL_DETECT_IRQ 1
+ #endif
+ #ifdef CONFIG_SERIAL_8250_MANY_PORTS
+ #define CONFIG_SERIAL_MANY_PORTS 1
+ #endif
+ /*
+  * HUB6 is always on.  This will be removed once the header
+  * files have been cleaned.
+  */
+ #define CONFIG_HUB6 1
+ #include <asm/serial.h>
+ /*
+  * SERIAL_PORT_DFNS tells us about built-in ports that have no
+  * standard enumeration mechanism.   Platforms that can find all
+  * serial ports via mechanisms like ACPI or PCI need not supply it.
+  */
+ #ifndef SERIAL_PORT_DFNS
+ #define SERIAL_PORT_DFNS
+ #endif
+ static const struct old_serial_port old_serial_port[] = {
+       SERIAL_PORT_DFNS /* defined in asm/serial.h */
+ };
+ #define UART_NR       CONFIG_SERIAL_8250_NR_UARTS
+ #ifdef CONFIG_SERIAL_8250_RSA
+ #define PORT_RSA_MAX 4
+ static unsigned long probe_rsa[PORT_RSA_MAX];
+ static unsigned int probe_rsa_count;
+ #endif /* CONFIG_SERIAL_8250_RSA  */
+ struct irq_info {
+       struct                  hlist_node node;
+       int                     irq;
+       spinlock_t              lock;   /* Protects list not the hash */
+       struct list_head        *head;
+ };
+ #define NR_IRQ_HASH           32      /* Can be adjusted later */
+ static struct hlist_head irq_lists[NR_IRQ_HASH];
+ static DEFINE_MUTEX(hash_mutex);      /* Used to walk the hash */
+ /*
+  * Here we define the default xmit fifo size used for each type of UART.
+  */
+ static const struct serial8250_config uart_config[] = {
+       [PORT_UNKNOWN] = {
+               .name           = "unknown",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_8250] = {
+               .name           = "8250",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_16450] = {
+               .name           = "16450",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_16550] = {
+               .name           = "16550",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_16550A] = {
+               .name           = "16550A",
+               .fifo_size      = 16,
+               .tx_loadsz      = 16,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO,
+       },
+       [PORT_CIRRUS] = {
+               .name           = "Cirrus",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_16650] = {
+               .name           = "ST16650",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+               .flags          = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+       },
+       [PORT_16650V2] = {
+               .name           = "ST16650V2",
+               .fifo_size      = 32,
+               .tx_loadsz      = 16,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+                                 UART_FCR_T_TRIG_00,
+               .flags          = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+       },
+       [PORT_16750] = {
+               .name           = "TI16750",
+               .fifo_size      = 64,
+               .tx_loadsz      = 64,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
+                                 UART_FCR7_64BYTE,
+               .flags          = UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE,
+       },
+       [PORT_STARTECH] = {
+               .name           = "Startech",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1,
+       },
+       [PORT_16C950] = {
+               .name           = "16C950/954",
+               .fifo_size      = 128,
+               .tx_loadsz      = 128,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               /* UART_CAP_EFR breaks billionon CF bluetooth card. */
+               .flags          = UART_CAP_FIFO | UART_CAP_SLEEP,
+       },
+       [PORT_16654] = {
+               .name           = "ST16654",
+               .fifo_size      = 64,
+               .tx_loadsz      = 32,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+                                 UART_FCR_T_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+       },
+       [PORT_16850] = {
+               .name           = "XR16850",
+               .fifo_size      = 128,
+               .tx_loadsz      = 128,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+       },
+       [PORT_RSA] = {
+               .name           = "RSA",
+               .fifo_size      = 2048,
+               .tx_loadsz      = 2048,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11,
+               .flags          = UART_CAP_FIFO,
+       },
+       [PORT_NS16550A] = {
+               .name           = "NS16550A",
+               .fifo_size      = 16,
+               .tx_loadsz      = 16,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_NATSEMI,
+       },
+       [PORT_XSCALE] = {
+               .name           = "XScale",
+               .fifo_size      = 32,
+               .tx_loadsz      = 32,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE,
+       },
+       [PORT_OCTEON] = {
+               .name           = "OCTEON",
+               .fifo_size      = 64,
+               .tx_loadsz      = 64,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO,
+       },
+       [PORT_AR7] = {
+               .name           = "AR7",
+               .fifo_size      = 16,
+               .tx_loadsz      = 16,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE,
+       },
+       [PORT_U6_16550A] = {
+               .name           = "U6_16550A",
+               .fifo_size      = 64,
+               .tx_loadsz      = 64,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE,
+       },
+       [PORT_TEGRA] = {
+               .name           = "Tegra",
+               .fifo_size      = 32,
+               .tx_loadsz      = 8,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+                                 UART_FCR_T_TRIG_01,
+               .flags          = UART_CAP_FIFO | UART_CAP_RTOIE,
+       },
+       [PORT_XR17D15X] = {
+               .name           = "XR17D15X",
+               .fifo_size      = 64,
+               .tx_loadsz      = 64,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
+                                 UART_CAP_SLEEP,
+       },
+       [PORT_XR17V35X] = {
+               .name           = "XR17V35X",
+               .fifo_size      = 256,
+               .tx_loadsz      = 256,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11 |
+                                 UART_FCR_T_TRIG_11,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
+                                 UART_CAP_SLEEP,
+       },
+       [PORT_LPC3220] = {
+               .name           = "LPC3220",
+               .fifo_size      = 64,
+               .tx_loadsz      = 32,
+               .fcr            = UART_FCR_DMA_SELECT | UART_FCR_ENABLE_FIFO |
+                                 UART_FCR_R_TRIG_00 | UART_FCR_T_TRIG_00,
+               .flags          = UART_CAP_FIFO,
+       },
+       [PORT_BRCM_TRUMANAGE] = {
+               .name           = "TruManage",
+               .fifo_size      = 1,
+               .tx_loadsz      = 1024,
+               .flags          = UART_CAP_HFIFO,
+       },
+       [PORT_8250_CIR] = {
+               .name           = "CIR port"
+       },
+       [PORT_ALTR_16550_F32] = {
+               .name           = "Altera 16550 FIFO32",
+               .fifo_size      = 32,
+               .tx_loadsz      = 32,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE,
+       },
+       [PORT_ALTR_16550_F64] = {
+               .name           = "Altera 16550 FIFO64",
+               .fifo_size      = 64,
+               .tx_loadsz      = 64,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE,
+       },
+       [PORT_ALTR_16550_F128] = {
+               .name           = "Altera 16550 FIFO128",
+               .fifo_size      = 128,
+               .tx_loadsz      = 128,
+               .fcr            = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+               .flags          = UART_CAP_FIFO | UART_CAP_AFE,
+       },
+ };
+ /* Uart divisor latch read */
+ static int default_serial_dl_read(struct uart_8250_port *up)
+ {
+       return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8;
+ }
+ /* Uart divisor latch write */
+ static void default_serial_dl_write(struct uart_8250_port *up, int value)
+ {
+       serial_out(up, UART_DLL, value & 0xff);
+       serial_out(up, UART_DLM, value >> 8 & 0xff);
+ }
+ #if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
+ /* Au1x00/RT288x UART hardware has a weird register layout */
+ static const u8 au_io_in_map[] = {
+       [UART_RX]  = 0,
+       [UART_IER] = 2,
+       [UART_IIR] = 3,
+       [UART_LCR] = 5,
+       [UART_MCR] = 6,
+       [UART_LSR] = 7,
+       [UART_MSR] = 8,
+ };
+ static const u8 au_io_out_map[] = {
+       [UART_TX]  = 1,
+       [UART_IER] = 2,
+       [UART_FCR] = 4,
+       [UART_LCR] = 5,
+       [UART_MCR] = 6,
+ };
+ static unsigned int au_serial_in(struct uart_port *p, int offset)
+ {
+       offset = au_io_in_map[offset] << p->regshift;
+       return __raw_readl(p->membase + offset);
+ }
+ static void au_serial_out(struct uart_port *p, int offset, int value)
+ {
+       offset = au_io_out_map[offset] << p->regshift;
+       __raw_writel(value, p->membase + offset);
+ }
+ /* Au1x00 haven't got a standard divisor latch */
+ static int au_serial_dl_read(struct uart_8250_port *up)
+ {
+       return __raw_readl(up->port.membase + 0x28);
+ }
+ static void au_serial_dl_write(struct uart_8250_port *up, int value)
+ {
+       __raw_writel(value, up->port.membase + 0x28);
+ }
+ #endif
+ static unsigned int hub6_serial_in(struct uart_port *p, int offset)
+ {
+       offset = offset << p->regshift;
+       outb(p->hub6 - 1 + offset, p->iobase);
+       return inb(p->iobase + 1);
+ }
+ static void hub6_serial_out(struct uart_port *p, int offset, int value)
+ {
+       offset = offset << p->regshift;
+       outb(p->hub6 - 1 + offset, p->iobase);
+       outb(value, p->iobase + 1);
+ }
+ static unsigned int mem_serial_in(struct uart_port *p, int offset)
+ {
+       offset = offset << p->regshift;
+       return readb(p->membase + offset);
+ }
+ static void mem_serial_out(struct uart_port *p, int offset, int value)
+ {
+       offset = offset << p->regshift;
+       writeb(value, p->membase + offset);
+ }
+ static void mem32_serial_out(struct uart_port *p, int offset, int value)
+ {
+       offset = offset << p->regshift;
+       writel(value, p->membase + offset);
+ }
+ static unsigned int mem32_serial_in(struct uart_port *p, int offset)
+ {
+       offset = offset << p->regshift;
+       return readl(p->membase + offset);
+ }
+ static unsigned int io_serial_in(struct uart_port *p, int offset)
+ {
+       offset = offset << p->regshift;
+       return inb(p->iobase + offset);
+ }
+ static void io_serial_out(struct uart_port *p, int offset, int value)
+ {
+       offset = offset << p->regshift;
+       outb(value, p->iobase + offset);
+ }
+ static int serial8250_default_handle_irq(struct uart_port *port);
+ static int exar_handle_irq(struct uart_port *port);
+ static void set_io_from_upio(struct uart_port *p)
+ {
+       struct uart_8250_port *up =
+               container_of(p, struct uart_8250_port, port);
+       up->dl_read = default_serial_dl_read;
+       up->dl_write = default_serial_dl_write;
+       switch (p->iotype) {
+       case UPIO_HUB6:
+               p->serial_in = hub6_serial_in;
+               p->serial_out = hub6_serial_out;
+               break;
+       case UPIO_MEM:
+               p->serial_in = mem_serial_in;
+               p->serial_out = mem_serial_out;
+               break;
+       case UPIO_MEM32:
+               p->serial_in = mem32_serial_in;
+               p->serial_out = mem32_serial_out;
+               break;
+ #if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
+       case UPIO_AU:
+               p->serial_in = au_serial_in;
+               p->serial_out = au_serial_out;
+               up->dl_read = au_serial_dl_read;
+               up->dl_write = au_serial_dl_write;
+               break;
+ #endif
+       default:
+               p->serial_in = io_serial_in;
+               p->serial_out = io_serial_out;
+               break;
+       }
+       /* Remember loaded iotype */
+       up->cur_iotype = p->iotype;
+       p->handle_irq = serial8250_default_handle_irq;
+ }
+ static void
+ serial_port_out_sync(struct uart_port *p, int offset, int value)
+ {
+       switch (p->iotype) {
+       case UPIO_MEM:
+       case UPIO_MEM32:
+       case UPIO_AU:
+               p->serial_out(p, offset, value);
+               p->serial_in(p, UART_LCR);      /* safe, no side-effects */
+               break;
+       default:
+               p->serial_out(p, offset, value);
+       }
+ }
+ /*
+  * For the 16C950
+  */
+ static void serial_icr_write(struct uart_8250_port *up, int offset, int value)
+ {
+       serial_out(up, UART_SCR, offset);
+       serial_out(up, UART_ICR, value);
+ }
+ static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
+ {
+       unsigned int value;
+       serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
+       serial_out(up, UART_SCR, offset);
+       value = serial_in(up, UART_ICR);
+       serial_icr_write(up, UART_ACR, up->acr);
+       return value;
+ }
+ /*
+  * FIFO support.
+  */
+ static void serial8250_clear_fifos(struct uart_8250_port *p)
+ {
+       if (p->capabilities & UART_CAP_FIFO) {
+               serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO);
+               serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO |
+                              UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+               serial_out(p, UART_FCR, 0);
+       }
+ }
+ void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p)
+ {
+       unsigned char fcr;
+       serial8250_clear_fifos(p);
+       fcr = uart_config[p->port.type].fcr;
+       serial_out(p, UART_FCR, fcr);
+ }
+ EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos);
+ /*
+  * IER sleep support.  UARTs which have EFRs need the "extended
+  * capability" bit enabled.  Note that on XR16C850s, we need to
+  * reset LCR to write to IER.
+  */
+ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
+ {
+       /*
+        * Exar UARTs have a SLEEP register that enables or disables
+        * each UART to enter sleep mode separately.  On the XR17V35x the
+        * register is accessible to each UART at the UART_EXAR_SLEEP
+        * offset but the UART channel may only write to the corresponding
+        * bit.
+        */
+       if ((p->port.type == PORT_XR17V35X) ||
+          (p->port.type == PORT_XR17D15X)) {
+               serial_out(p, UART_EXAR_SLEEP, 0xff);
+               return;
+       }
+       if (p->capabilities & UART_CAP_SLEEP) {
+               if (p->capabilities & UART_CAP_EFR) {
+                       serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+                       serial_out(p, UART_EFR, UART_EFR_ECB);
+                       serial_out(p, UART_LCR, 0);
+               }
+               serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+               if (p->capabilities & UART_CAP_EFR) {
+                       serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+                       serial_out(p, UART_EFR, 0);
+                       serial_out(p, UART_LCR, 0);
+               }
+       }
+ }
+ #ifdef CONFIG_SERIAL_8250_RSA
+ /*
+  * Attempts to turn on the RSA FIFO.  Returns zero on failure.
+  * We set the port uart clock rate if we succeed.
+  */
+ static int __enable_rsa(struct uart_8250_port *up)
+ {
+       unsigned char mode;
+       int result;
+       mode = serial_in(up, UART_RSA_MSR);
+       result = mode & UART_RSA_MSR_FIFO;
+       if (!result) {
+               serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
+               mode = serial_in(up, UART_RSA_MSR);
+               result = mode & UART_RSA_MSR_FIFO;
+       }
+       if (result)
+               up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
+       return result;
+ }
+ static void enable_rsa(struct uart_8250_port *up)
+ {
+       if (up->port.type == PORT_RSA) {
+               if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
+                       spin_lock_irq(&up->port.lock);
+                       __enable_rsa(up);
+                       spin_unlock_irq(&up->port.lock);
+               }
+               if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
+                       serial_out(up, UART_RSA_FRR, 0);
+       }
+ }
+ /*
+  * Attempts to turn off the RSA FIFO.  Returns zero on failure.
+  * It is unknown why interrupts were disabled in here.  However,
+  * the caller is expected to preserve this behaviour by grabbing
+  * the spinlock before calling this function.
+  */
+ static void disable_rsa(struct uart_8250_port *up)
+ {
+       unsigned char mode;
+       int result;
+       if (up->port.type == PORT_RSA &&
+           up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
+               spin_lock_irq(&up->port.lock);
+               mode = serial_in(up, UART_RSA_MSR);
+               result = !(mode & UART_RSA_MSR_FIFO);
+               if (!result) {
+                       serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
+                       mode = serial_in(up, UART_RSA_MSR);
+                       result = !(mode & UART_RSA_MSR_FIFO);
+               }
+               if (result)
+                       up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
+               spin_unlock_irq(&up->port.lock);
+       }
+ }
+ #endif /* CONFIG_SERIAL_8250_RSA */
+ /*
+  * This is a quickie test to see how big the FIFO is.
+  * It doesn't work at all the time, more's the pity.
+  */
+ static int size_fifo(struct uart_8250_port *up)
+ {
+       unsigned char old_fcr, old_mcr, old_lcr;
+       unsigned short old_dl;
+       int count;
+       old_lcr = serial_in(up, UART_LCR);
+       serial_out(up, UART_LCR, 0);
+       old_fcr = serial_in(up, UART_FCR);
+       old_mcr = serial_in(up, UART_MCR);
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+                   UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+       serial_out(up, UART_MCR, UART_MCR_LOOP);
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+       old_dl = serial_dl_read(up);
+       serial_dl_write(up, 0x0001);
+       serial_out(up, UART_LCR, 0x03);
+       for (count = 0; count < 256; count++)
+               serial_out(up, UART_TX, count);
+       mdelay(20);/* FIXME - schedule_timeout */
+       for (count = 0; (serial_in(up, UART_LSR) & UART_LSR_DR) &&
+            (count < 256); count++)
+               serial_in(up, UART_RX);
+       serial_out(up, UART_FCR, old_fcr);
+       serial_out(up, UART_MCR, old_mcr);
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+       serial_dl_write(up, old_dl);
+       serial_out(up, UART_LCR, old_lcr);
+       return count;
+ }
+ /*
+  * Read UART ID using the divisor method - set DLL and DLM to zero
+  * and the revision will be in DLL and device type in DLM.  We
+  * preserve the device state across this.
+  */
+ static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
+ {
+       unsigned char old_dll, old_dlm, old_lcr;
+       unsigned int id;
+       old_lcr = serial_in(p, UART_LCR);
+       serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A);
+       old_dll = serial_in(p, UART_DLL);
+       old_dlm = serial_in(p, UART_DLM);
+       serial_out(p, UART_DLL, 0);
+       serial_out(p, UART_DLM, 0);
+       id = serial_in(p, UART_DLL) | serial_in(p, UART_DLM) << 8;
+       serial_out(p, UART_DLL, old_dll);
+       serial_out(p, UART_DLM, old_dlm);
+       serial_out(p, UART_LCR, old_lcr);
+       return id;
+ }
+ /*
+  * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's.
+  * When this function is called we know it is at least a StarTech
+  * 16650 V2, but it might be one of several StarTech UARTs, or one of
+  * its clones.  (We treat the broken original StarTech 16650 V1 as a
+  * 16550, and why not?  Startech doesn't seem to even acknowledge its
+  * existence.)
+  *
+  * What evil have men's minds wrought...
+  */
+ static void autoconfig_has_efr(struct uart_8250_port *up)
+ {
+       unsigned int id1, id2, id3, rev;
+       /*
+        * Everything with an EFR has SLEEP
+        */
+       up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
+       /*
+        * First we check to see if it's an Oxford Semiconductor UART.
+        *
+        * If we have to do this here because some non-National
+        * Semiconductor clone chips lock up if you try writing to the
+        * LSR register (which serial_icr_read does)
+        */
+       /*
+        * Check for Oxford Semiconductor 16C950.
+        *
+        * EFR [4] must be set else this test fails.
+        *
+        * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca)
+        * claims that it's needed for 952 dual UART's (which are not
+        * recommended for new designs).
+        */
+       up->acr = 0;
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+       serial_out(up, UART_EFR, UART_EFR_ECB);
+       serial_out(up, UART_LCR, 0x00);
+       id1 = serial_icr_read(up, UART_ID1);
+       id2 = serial_icr_read(up, UART_ID2);
+       id3 = serial_icr_read(up, UART_ID3);
+       rev = serial_icr_read(up, UART_REV);
+       DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev);
+       if (id1 == 0x16 && id2 == 0xC9 &&
+           (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) {
+               up->port.type = PORT_16C950;
+               /*
+                * Enable work around for the Oxford Semiconductor 952 rev B
+                * chip which causes it to seriously miscalculate baud rates
+                * when DLL is 0.
+                */
+               if (id3 == 0x52 && rev == 0x01)
+                       up->bugs |= UART_BUG_QUOT;
+               return;
+       }
+       /*
+        * We check for a XR16C850 by setting DLL and DLM to 0, and then
+        * reading back DLL and DLM.  The chip type depends on the DLM
+        * value read back:
+        *  0x10 - XR16C850 and the DLL contains the chip revision.
+        *  0x12 - XR16C2850.
+        *  0x14 - XR16C854.
+        */
+       id1 = autoconfig_read_divisor_id(up);
+       DEBUG_AUTOCONF("850id=%04x ", id1);
+       id2 = id1 >> 8;
+       if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) {
+               up->port.type = PORT_16850;
+               return;
+       }
+       /*
+        * It wasn't an XR16C850.
+        *
+        * We distinguish between the '654 and the '650 by counting
+        * how many bytes are in the FIFO.  I'm using this for now,
+        * since that's the technique that was sent to me in the
+        * serial driver update, but I'm not convinced this works.
+        * I've had problems doing this in the past.  -TYT
+        */
+       if (size_fifo(up) == 64)
+               up->port.type = PORT_16654;
+       else
+               up->port.type = PORT_16650V2;
+ }
+ /*
+  * We detected a chip without a FIFO.  Only two fall into
+  * this category - the original 8250 and the 16450.  The
+  * 16450 has a scratch register (accessible with LCR=0)
+  */
+ static void autoconfig_8250(struct uart_8250_port *up)
+ {
+       unsigned char scratch, status1, status2;
+       up->port.type = PORT_8250;
+       scratch = serial_in(up, UART_SCR);
+       serial_out(up, UART_SCR, 0xa5);
+       status1 = serial_in(up, UART_SCR);
+       serial_out(up, UART_SCR, 0x5a);
+       status2 = serial_in(up, UART_SCR);
+       serial_out(up, UART_SCR, scratch);
+       if (status1 == 0xa5 && status2 == 0x5a)
+               up->port.type = PORT_16450;
+ }
+ static int broken_efr(struct uart_8250_port *up)
+ {
+       /*
+        * Exar ST16C2550 "A2" devices incorrectly detect as
+        * having an EFR, and report an ID of 0x0201.  See
+        * http://linux.derkeiler.com/Mailing-Lists/Kernel/2004-11/4812.html 
+        */
+       if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16)
+               return 1;
+       return 0;
+ }
+ static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
+ {
+       unsigned char status;
+       status = serial_in(up, 0x04); /* EXCR2 */
+ #define PRESL(x) ((x) & 0x30)
+       if (PRESL(status) == 0x10) {
+               /* already in high speed mode */
+               return 0;
+       } else {
+               status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
+               status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
+               serial_out(up, 0x04, status);
+       }
+       return 1;
+ }
+ /*
+  * We know that the chip has FIFOs.  Does it have an EFR?  The
+  * EFR is located in the same register position as the IIR and
+  * we know the top two bits of the IIR are currently set.  The
+  * EFR should contain zero.  Try to read the EFR.
+  */
+ static void autoconfig_16550a(struct uart_8250_port *up)
+ {
+       unsigned char status1, status2;
+       unsigned int iersave;
+       up->port.type = PORT_16550A;
+       up->capabilities |= UART_CAP_FIFO;
+       /*
+        * XR17V35x UARTs have an extra divisor register, DLD
+        * that gets enabled with when DLAB is set which will
+        * cause the device to incorrectly match and assign
+        * port type to PORT_16650.  The EFR for this UART is
+        * found at offset 0x09. Instead check the Deice ID (DVID)
+        * register for a 2, 4 or 8 port UART.
+        */
+       if (up->port.flags & UPF_EXAR_EFR) {
+               status1 = serial_in(up, UART_EXAR_DVID);
+               if (status1 == 0x82 || status1 == 0x84 || status1 == 0x88) {
+                       DEBUG_AUTOCONF("Exar XR17V35x ");
+                       up->port.type = PORT_XR17V35X;
+                       up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
+                                               UART_CAP_SLEEP;
+                       return;
+               }
+       }
+       /*
+        * Check for presence of the EFR when DLAB is set.
+        * Only ST16C650V1 UARTs pass this test.
+        */
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+       if (serial_in(up, UART_EFR) == 0) {
+               serial_out(up, UART_EFR, 0xA8);
+               if (serial_in(up, UART_EFR) != 0) {
+                       DEBUG_AUTOCONF("EFRv1 ");
+                       up->port.type = PORT_16650;
+                       up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
+               } else {
+                       DEBUG_AUTOCONF("Motorola 8xxx DUART ");
+               }
+               serial_out(up, UART_EFR, 0);
+               return;
+       }
+       /*
+        * Maybe it requires 0xbf to be written to the LCR.
+        * (other ST16C650V2 UARTs, TI16C752A, etc)
+        */
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+       if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
+               DEBUG_AUTOCONF("EFRv2 ");
+               autoconfig_has_efr(up);
+               return;
+       }
+       /*
+        * Check for a National Semiconductor SuperIO chip.
+        * Attempt to switch to bank 2, read the value of the LOOP bit
+        * from EXCR1. Switch back to bank 0, change it in MCR. Then
+        * switch back to bank 2, read it from EXCR1 again and check
+        * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2
+        */
+       serial_out(up, UART_LCR, 0);
+       status1 = serial_in(up, UART_MCR);
+       serial_out(up, UART_LCR, 0xE0);
+       status2 = serial_in(up, 0x02); /* EXCR1 */
+       if (!((status2 ^ status1) & UART_MCR_LOOP)) {
+               serial_out(up, UART_LCR, 0);
+               serial_out(up, UART_MCR, status1 ^ UART_MCR_LOOP);
+               serial_out(up, UART_LCR, 0xE0);
+               status2 = serial_in(up, 0x02); /* EXCR1 */
+               serial_out(up, UART_LCR, 0);
+               serial_out(up, UART_MCR, status1);
+               if ((status2 ^ status1) & UART_MCR_LOOP) {
+                       unsigned short quot;
+                       serial_out(up, UART_LCR, 0xE0);
+                       quot = serial_dl_read(up);
+                       quot <<= 3;
+                       if (ns16550a_goto_highspeed(up))
+                               serial_dl_write(up, quot);
+                       serial_out(up, UART_LCR, 0);
+                       up->port.uartclk = 921600*16;
+                       up->port.type = PORT_NS16550A;
+                       up->capabilities |= UART_NATSEMI;
+                       return;
+               }
+       }
+       /*
+        * No EFR.  Try to detect a TI16750, which only sets bit 5 of
+        * the IIR when 64 byte FIFO mode is enabled when DLAB is set.
+        * Try setting it with and without DLAB set.  Cheap clones
+        * set bit 5 without DLAB set.
+        */
+       serial_out(up, UART_LCR, 0);
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+       status1 = serial_in(up, UART_IIR) >> 5;
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+       status2 = serial_in(up, UART_IIR) >> 5;
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+       serial_out(up, UART_LCR, 0);
+       DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);
+       if (status1 == 6 && status2 == 7) {
+               up->port.type = PORT_16750;
+               up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;
+               return;
+       }
+       /*
+        * Try writing and reading the UART_IER_UUE bit (b6).
+        * If it works, this is probably one of the Xscale platform's
+        * internal UARTs.
+        * We're going to explicitly set the UUE bit to 0 before
+        * trying to write and read a 1 just to make sure it's not
+        * already a 1 and maybe locked there before we even start start.
+        */
+       iersave = serial_in(up, UART_IER);
+       serial_out(up, UART_IER, iersave & ~UART_IER_UUE);
+       if (!(serial_in(up, UART_IER) & UART_IER_UUE)) {
+               /*
+                * OK it's in a known zero state, try writing and reading
+                * without disturbing the current state of the other bits.
+                */
+               serial_out(up, UART_IER, iersave | UART_IER_UUE);
+               if (serial_in(up, UART_IER) & UART_IER_UUE) {
+                       /*
+                        * It's an Xscale.
+                        * We'll leave the UART_IER_UUE bit set to 1 (enabled).
+                        */
+                       DEBUG_AUTOCONF("Xscale ");
+                       up->port.type = PORT_XSCALE;
+                       up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE;
+                       return;
+               }
+       } else {
+               /*
+                * If we got here we couldn't force the IER_UUE bit to 0.
+                * Log it and continue.
+                */
+               DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 ");
+       }
+       serial_out(up, UART_IER, iersave);
+       /*
+        * Exar uarts have EFR in a weird location
+        */
+       if (up->port.flags & UPF_EXAR_EFR) {
+               DEBUG_AUTOCONF("Exar XR17D15x ");
+               up->port.type = PORT_XR17D15X;
+               up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
+                                   UART_CAP_SLEEP;
+               return;
+       }
+       /*
+        * We distinguish between 16550A and U6 16550A by counting
+        * how many bytes are in the FIFO.
+        */
+       if (up->port.type == PORT_16550A && size_fifo(up) == 64) {
+               up->port.type = PORT_U6_16550A;
+               up->capabilities |= UART_CAP_AFE;
+       }
+ }
+ /*
+  * This routine is called by rs_init() to initialize a specific serial
+  * port.  It determines what type of UART chip this serial port is
+  * using: 8250, 16450, 16550, 16550A.  The important question is
+  * whether or not this UART is a 16550A or not, since this will
+  * determine whether or not we can use its FIFO features or not.
+  */
+ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
+ {
+       unsigned char status1, scratch, scratch2, scratch3;
+       unsigned char save_lcr, save_mcr;
+       struct uart_port *port = &up->port;
+       unsigned long flags;
+       unsigned int old_capabilities;
+       if (!port->iobase && !port->mapbase && !port->membase)
+               return;
+       DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04lx, 0x%p): ",
+                      serial_index(port), port->iobase, port->membase);
+       /*
+        * We really do need global IRQs disabled here - we're going to
+        * be frobbing the chips IRQ enable register to see if it exists.
+        */
+       spin_lock_irqsave(&port->lock, flags);
+       up->capabilities = 0;
+       up->bugs = 0;
+       if (!(port->flags & UPF_BUGGY_UART)) {
+               /*
+                * Do a simple existence test first; if we fail this,
+                * there's no point trying anything else.
+                *
+                * 0x80 is used as a nonsense port to prevent against
+                * false positives due to ISA bus float.  The
+                * assumption is that 0x80 is a non-existent port;
+                * which should be safe since include/asm/io.h also
+                * makes this assumption.
+                *
+                * Note: this is safe as long as MCR bit 4 is clear
+                * and the device is in "PC" mode.
+                */
+               scratch = serial_in(up, UART_IER);
+               serial_out(up, UART_IER, 0);
+ #ifdef __i386__
+               outb(0xff, 0x080);
+ #endif
+               /*
+                * Mask out IER[7:4] bits for test as some UARTs (e.g. TL
+                * 16C754B) allow only to modify them if an EFR bit is set.
+                */
+               scratch2 = serial_in(up, UART_IER) & 0x0f;
+               serial_out(up, UART_IER, 0x0F);
+ #ifdef __i386__
+               outb(0, 0x080);
+ #endif
+               scratch3 = serial_in(up, UART_IER) & 0x0f;
+               serial_out(up, UART_IER, scratch);
+               if (scratch2 != 0 || scratch3 != 0x0F) {
+                       /*
+                        * We failed; there's nothing here
+                        */
+                       spin_unlock_irqrestore(&port->lock, flags);
+                       DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
+                                      scratch2, scratch3);
+                       goto out;
+               }
+       }
+       save_mcr = serial_in(up, UART_MCR);
+       save_lcr = serial_in(up, UART_LCR);
+       /*
+        * Check to see if a UART is really there.  Certain broken
+        * internal modems based on the Rockwell chipset fail this
+        * test, because they apparently don't implement the loopback
+        * test mode.  So this test is skipped on the COM 1 through
+        * COM 4 ports.  This *should* be safe, since no board
+        * manufacturer would be stupid enough to design a board
+        * that conflicts with COM 1-4 --- we hope!
+        */
+       if (!(port->flags & UPF_SKIP_TEST)) {
+               serial_out(up, UART_MCR, UART_MCR_LOOP | 0x0A);
+               status1 = serial_in(up, UART_MSR) & 0xF0;
+               serial_out(up, UART_MCR, save_mcr);
+               if (status1 != 0x90) {
+                       spin_unlock_irqrestore(&port->lock, flags);
+                       DEBUG_AUTOCONF("LOOP test failed (%02x) ",
+                                      status1);
+                       goto out;
+               }
+       }
+       /*
+        * We're pretty sure there's a port here.  Lets find out what
+        * type of port it is.  The IIR top two bits allows us to find
+        * out if it's 8250 or 16450, 16550, 16550A or later.  This
+        * determines what we test for next.
+        *
+        * We also initialise the EFR (if any) to zero for later.  The
+        * EFR occupies the same register location as the FCR and IIR.
+        */
+       serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+       serial_out(up, UART_EFR, 0);
+       serial_out(up, UART_LCR, 0);
+       serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+       scratch = serial_in(up, UART_IIR) >> 6;
+       switch (scratch) {
+       case 0:
+               autoconfig_8250(up);
+               break;
+       case 1:
+               port->type = PORT_UNKNOWN;
+               break;
+       case 2:
+               port->type = PORT_16550;
+               break;
+       case 3:
+               autoconfig_16550a(up);
+               break;
+       }
+ #ifdef CONFIG_SERIAL_8250_RSA
+       /*
+        * Only probe for RSA ports if we got the region.
+        */
+       if (port->type == PORT_16550A && probeflags & PROBE_RSA) {
+               int i;
+               for (i = 0 ; i < probe_rsa_count; ++i) {
+                       if (probe_rsa[i] == port->iobase && __enable_rsa(up)) {
+                               port->type = PORT_RSA;
+                               break;
+                       }
+               }
+       }
+ #endif
+       serial_out(up, UART_LCR, save_lcr);
+       port->fifosize = uart_config[up->port.type].fifo_size;
+       old_capabilities = up->capabilities; 
+       up->capabilities = uart_config[port->type].flags;
+       up->tx_loadsz = uart_config[port->type].tx_loadsz;
+       if (port->type == PORT_UNKNOWN)
+               goto out_lock;
+       /*
+        * Reset the UART.
+        */
+ #ifdef CONFIG_SERIAL_8250_RSA
+       if (port->type == PORT_RSA)
+               serial_out(up, UART_RSA_FRR, 0);
+ #endif
+       serial_out(up, UART_MCR, save_mcr);
+       serial8250_clear_fifos(up);
+       serial_in(up, UART_RX);
+       if (up->capabilities & UART_CAP_UUE)
+               serial_out(up, UART_IER, UART_IER_UUE);
+       else
+               serial_out(up, UART_IER, 0);
+ out_lock:
+       spin_unlock_irqrestore(&port->lock, flags);
+       if (up->capabilities != old_capabilities) {
+               printk(KERN_WARNING
+                      "ttyS%d: detected caps %08x should be %08x\n",
+                      serial_index(port), old_capabilities,
+                      up->capabilities);
+       }
+ out:
+       DEBUG_AUTOCONF("iir=%d ", scratch);
+       DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name);
+ }
+ static void autoconfig_irq(struct uart_8250_port *up)
+ {
+       struct uart_port *port = &up->port;
+       unsigned char save_mcr, save_ier;
+       unsigned char save_ICP = 0;
+       unsigned int ICP = 0;
+       unsigned long irqs;
+       int irq;
+       if (port->flags & UPF_FOURPORT) {
+               ICP = (port->iobase & 0xfe0) | 0x1f;
+               save_ICP = inb_p(ICP);
+               outb_p(0x80, ICP);
+               inb_p(ICP);
+       }
+       /* forget possible initially masked and pending IRQ */
+       probe_irq_off(probe_irq_on());
+       save_mcr = serial_in(up, UART_MCR);
+       save_ier = serial_in(up, UART_IER);
+       serial_out(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
+       irqs = probe_irq_on();
+       serial_out(up, UART_MCR, 0);
+       udelay(10);
+       if (port->flags & UPF_FOURPORT) {
+               serial_out(up, UART_MCR,
+                           UART_MCR_DTR | UART_MCR_RTS);
+       } else {
+               serial_out(up, UART_MCR,
+                           UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
+       }
+       serial_out(up, UART_IER, 0x0f); /* enable all intrs */
+       serial_in(up, UART_LSR);
+       serial_in(up, UART_RX);
+       serial_in(up, UART_IIR);
+       serial_in(up, UART_MSR);
+       serial_out(up, UART_TX, 0xFF);
+       udelay(20);
+       irq = probe_irq_off(irqs);
+       serial_out(up, UART_MCR, save_mcr);
+       serial_out(up, UART_IER, save_ier);
+       if (port->flags & UPF_FOURPORT)
+               outb_p(save_ICP, ICP);
+       port->irq = (irq > 0) ? irq : 0;
+ }
+ static inline void __stop_tx(struct uart_8250_port *p)
+ {
+       if (p->ier & UART_IER_THRI) {
+               p->ier &= ~UART_IER_THRI;
+               serial_out(p, UART_IER, p->ier);
+       }
+ }
+ static void serial8250_stop_tx(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       __stop_tx(up);
+       /*
+        * We really want to stop the transmitter from sending.
+        */
+       if (port->type == PORT_16C950) {
+               up->acr |= UART_ACR_TXDIS;
+               serial_icr_write(up, UART_ACR, up->acr);
+       }
+ }
+ static void serial8250_start_tx(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       if (up->dma && !serial8250_tx_dma(up)) {
+               return;
+       } else if (!(up->ier & UART_IER_THRI)) {
+               up->ier |= UART_IER_THRI;
+               serial_port_out(port, UART_IER, up->ier);
+               if (up->bugs & UART_BUG_TXEN) {
+                       unsigned char lsr;
+                       lsr = serial_in(up, UART_LSR);
+                       up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+                       if (lsr & UART_LSR_TEMT)
+                               serial8250_tx_chars(up);
+               }
+       }
+       /*
+        * Re-enable the transmitter if we disabled it.
+        */
+       if (port->type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
+               up->acr &= ~UART_ACR_TXDIS;
+               serial_icr_write(up, UART_ACR, up->acr);
+       }
+ }
+ static void serial8250_stop_rx(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       up->ier &= ~UART_IER_RLSI;
+       up->port.read_status_mask &= ~UART_LSR_DR;
+       serial_port_out(port, UART_IER, up->ier);
+ }
+ static void serial8250_enable_ms(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       /* no MSR capabilities */
+       if (up->bugs & UART_BUG_NOMSR)
+               return;
+       up->ier |= UART_IER_MSI;
+       serial_port_out(port, UART_IER, up->ier);
+ }
+ /*
+  * serial8250_rx_chars: processes according to the passed in LSR
+  * value, and returns the remaining LSR bits not handled
+  * by this Rx routine.
+  */
+ unsigned char
+ serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
+ {
+       struct uart_port *port = &up->port;
+       unsigned char ch;
+       int max_count = 256;
+       char flag;
+       do {
+               if (likely(lsr & UART_LSR_DR))
+                       ch = serial_in(up, UART_RX);
+               else
+                       /*
+                        * Intel 82571 has a Serial Over Lan device that will
+                        * set UART_LSR_BI without setting UART_LSR_DR when
+                        * it receives a break. To avoid reading from the
+                        * receive buffer without UART_LSR_DR bit set, we
+                        * just force the read character to be 0
+                        */
+                       ch = 0;
+               flag = TTY_NORMAL;
+               port->icount.rx++;
+               lsr |= up->lsr_saved_flags;
+               up->lsr_saved_flags = 0;
+               if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
+                       if (lsr & UART_LSR_BI) {
+                               lsr &= ~(UART_LSR_FE | UART_LSR_PE);
+                               port->icount.brk++;
+                               /*
+                                * We do the SysRQ and SAK checking
+                                * here because otherwise the break
+                                * may get masked by ignore_status_mask
+                                * or read_status_mask.
+                                */
+                               if (uart_handle_break(port))
+                                       goto ignore_char;
+                       } else if (lsr & UART_LSR_PE)
+                               port->icount.parity++;
+                       else if (lsr & UART_LSR_FE)
+                               port->icount.frame++;
+                       if (lsr & UART_LSR_OE)
+                               port->icount.overrun++;
+                       /*
+                        * Mask off conditions which should be ignored.
+                        */
+                       lsr &= port->read_status_mask;
+                       if (lsr & UART_LSR_BI) {
+                               DEBUG_INTR("handling break....");
+                               flag = TTY_BREAK;
+                       } else if (lsr & UART_LSR_PE)
+                               flag = TTY_PARITY;
+                       else if (lsr & UART_LSR_FE)
+                               flag = TTY_FRAME;
+               }
+               if (uart_handle_sysrq_char(port, ch))
+                       goto ignore_char;
+               uart_insert_char(port, lsr, UART_LSR_OE, ch, flag);
+ ignore_char:
+               lsr = serial_in(up, UART_LSR);
+       } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
+       spin_unlock(&port->lock);
+       tty_flip_buffer_push(&port->state->port);
+       spin_lock(&port->lock);
+       return lsr;
+ }
+ EXPORT_SYMBOL_GPL(serial8250_rx_chars);
+ void serial8250_tx_chars(struct uart_8250_port *up)
+ {
+       struct uart_port *port = &up->port;
+       struct circ_buf *xmit = &port->state->xmit;
+       int count;
+       if (port->x_char) {
+               serial_out(up, UART_TX, port->x_char);
+               port->icount.tx++;
+               port->x_char = 0;
+               return;
+       }
+       if (uart_tx_stopped(port)) {
+               serial8250_stop_tx(port);
+               return;
+       }
+       if (uart_circ_empty(xmit)) {
+               __stop_tx(up);
+               return;
+       }
+       count = up->tx_loadsz;
+       do {
+               serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+               xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+               port->icount.tx++;
+               if (uart_circ_empty(xmit))
+                       break;
+               if (up->capabilities & UART_CAP_HFIFO) {
+                       if ((serial_port_in(port, UART_LSR) & BOTH_EMPTY) !=
+                           BOTH_EMPTY)
+                               break;
+               }
+       } while (--count > 0);
+       if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+               uart_write_wakeup(port);
+       DEBUG_INTR("THRE...");
+       if (uart_circ_empty(xmit))
+               __stop_tx(up);
+ }
+ EXPORT_SYMBOL_GPL(serial8250_tx_chars);
+ unsigned int serial8250_modem_status(struct uart_8250_port *up)
+ {
+       struct uart_port *port = &up->port;
+       unsigned int status = serial_in(up, UART_MSR);
+       status |= up->msr_saved_flags;
+       up->msr_saved_flags = 0;
+       if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
+           port->state != NULL) {
+               if (status & UART_MSR_TERI)
+                       port->icount.rng++;
+               if (status & UART_MSR_DDSR)
+                       port->icount.dsr++;
+               if (status & UART_MSR_DDCD)
+                       uart_handle_dcd_change(port, status & UART_MSR_DCD);
+               if (status & UART_MSR_DCTS)
+                       uart_handle_cts_change(port, status & UART_MSR_CTS);
+               wake_up_interruptible(&port->state->port.delta_msr_wait);
+       }
+       return status;
+ }
+ EXPORT_SYMBOL_GPL(serial8250_modem_status);
+ /*
+  * This handles the interrupt from one port.
+  */
+ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
+ {
+       unsigned char status;
+       unsigned long flags;
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       int dma_err = 0;
+       if (iir & UART_IIR_NO_INT)
+               return 0;
+       spin_lock_irqsave(&port->lock, flags);
+       status = serial_port_in(port, UART_LSR);
+       DEBUG_INTR("status = %x...", status);
+       if (status & (UART_LSR_DR | UART_LSR_BI)) {
+               if (up->dma)
+                       dma_err = serial8250_rx_dma(up, iir);
+               if (!up->dma || dma_err)
+                       status = serial8250_rx_chars(up, status);
+       }
+       serial8250_modem_status(up);
+       if (status & UART_LSR_THRE)
+               serial8250_tx_chars(up);
+       spin_unlock_irqrestore(&port->lock, flags);
+       return 1;
+ }
+ EXPORT_SYMBOL_GPL(serial8250_handle_irq);
+ static int serial8250_default_handle_irq(struct uart_port *port)
+ {
+       unsigned int iir = serial_port_in(port, UART_IIR);
+       return serial8250_handle_irq(port, iir);
+ }
+ /*
+  * These Exar UARTs have an extra interrupt indicator that could
+  * fire for a few unimplemented interrupts.  One of which is a
+  * wakeup event when coming out of sleep.  Put this here just
+  * to be on the safe side that these interrupts don't go unhandled.
+  */
+ static int exar_handle_irq(struct uart_port *port)
+ {
+       unsigned char int0, int1, int2, int3;
+       unsigned int iir = serial_port_in(port, UART_IIR);
+       int ret;
+       ret = serial8250_handle_irq(port, iir);
+       if ((port->type == PORT_XR17V35X) ||
+          (port->type == PORT_XR17D15X)) {
+               int0 = serial_port_in(port, 0x80);
+               int1 = serial_port_in(port, 0x81);
+               int2 = serial_port_in(port, 0x82);
+               int3 = serial_port_in(port, 0x83);
+       }
+       return ret;
+ }
+ /*
+  * This is the serial driver's interrupt routine.
+  *
+  * Arjan thinks the old way was overly complex, so it got simplified.
+  * Alan disagrees, saying that need the complexity to handle the weird
+  * nature of ISA shared interrupts.  (This is a special exception.)
+  *
+  * In order to handle ISA shared interrupts properly, we need to check
+  * that all ports have been serviced, and therefore the ISA interrupt
+  * line has been de-asserted.
+  *
+  * This means we need to loop through all ports. checking that they
+  * don't have an interrupt pending.
+  */
+ static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
+ {
+       struct irq_info *i = dev_id;
+       struct list_head *l, *end = NULL;
+       int pass_counter = 0, handled = 0;
+       DEBUG_INTR("serial8250_interrupt(%d)...", irq);
+       spin_lock(&i->lock);
+       l = i->head;
+       do {
+               struct uart_8250_port *up;
+               struct uart_port *port;
+               up = list_entry(l, struct uart_8250_port, list);
+               port = &up->port;
+               if (port->handle_irq(port)) {
+                       handled = 1;
+                       end = NULL;
+               } else if (end == NULL)
+                       end = l;
+               l = l->next;
+               if (l == i->head && pass_counter++ > PASS_LIMIT) {
+                       /* If we hit this, we're dead. */
+                       printk_ratelimited(KERN_ERR
+                               "serial8250: too much work for irq%d\n", irq);
+                       break;
+               }
+       } while (l != end);
+       spin_unlock(&i->lock);
+       DEBUG_INTR("end.\n");
+       return IRQ_RETVAL(handled);
+ }
+ /*
+  * To support ISA shared interrupts, we need to have one interrupt
+  * handler that ensures that the IRQ line has been deasserted
+  * before returning.  Failing to do this will result in the IRQ
+  * line being stuck active, and, since ISA irqs are edge triggered,
+  * no more IRQs will be seen.
+  */
+ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
+ {
+       spin_lock_irq(&i->lock);
+       if (!list_empty(i->head)) {
+               if (i->head == &up->list)
+                       i->head = i->head->next;
+               list_del(&up->list);
+       } else {
+               BUG_ON(i->head != &up->list);
+               i->head = NULL;
+       }
+       spin_unlock_irq(&i->lock);
+       /* List empty so throw away the hash node */
+       if (i->head == NULL) {
+               hlist_del(&i->node);
+               kfree(i);
+       }
+ }
+ static int serial_link_irq_chain(struct uart_8250_port *up)
+ {
+       struct hlist_head *h;
+       struct hlist_node *n;
+       struct irq_info *i;
+       int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
+       mutex_lock(&hash_mutex);
+       h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+       hlist_for_each(n, h) {
+               i = hlist_entry(n, struct irq_info, node);
+               if (i->irq == up->port.irq)
+                       break;
+       }
+       if (n == NULL) {
+               i = kzalloc(sizeof(struct irq_info), GFP_KERNEL);
+               if (i == NULL) {
+                       mutex_unlock(&hash_mutex);
+                       return -ENOMEM;
+               }
+               spin_lock_init(&i->lock);
+               i->irq = up->port.irq;
+               hlist_add_head(&i->node, h);
+       }
+       mutex_unlock(&hash_mutex);
+       spin_lock_irq(&i->lock);
+       if (i->head) {
+               list_add(&up->list, i->head);
+               spin_unlock_irq(&i->lock);
+               ret = 0;
+       } else {
+               INIT_LIST_HEAD(&up->list);
+               i->head = &up->list;
+               spin_unlock_irq(&i->lock);
+               irq_flags |= up->port.irqflags;
+               ret = request_irq(up->port.irq, serial8250_interrupt,
+                                 irq_flags, "serial", i);
+               if (ret < 0)
+                       serial_do_unlink(i, up);
+       }
+       return ret;
+ }
+ static void serial_unlink_irq_chain(struct uart_8250_port *up)
+ {
+       struct irq_info *i;
+       struct hlist_node *n;
+       struct hlist_head *h;
+       mutex_lock(&hash_mutex);
+       h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+       hlist_for_each(n, h) {
+               i = hlist_entry(n, struct irq_info, node);
+               if (i->irq == up->port.irq)
+                       break;
+       }
+       BUG_ON(n == NULL);
+       BUG_ON(i->head == NULL);
+       if (list_empty(i->head))
+               free_irq(up->port.irq, i);
+       serial_do_unlink(i, up);
+       mutex_unlock(&hash_mutex);
+ }
+ /*
+  * This function is used to handle ports that do not have an
+  * interrupt.  This doesn't work very well for 16450's, but gives
+  * barely passable results for a 16550A.  (Although at the expense
+  * of much CPU overhead).
+  */
+ static void serial8250_timeout(unsigned long data)
+ {
+       struct uart_8250_port *up = (struct uart_8250_port *)data;
+       up->port.handle_irq(&up->port);
+       mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port));
+ }
+ static void serial8250_backup_timeout(unsigned long data)
+ {
+       struct uart_8250_port *up = (struct uart_8250_port *)data;
+       unsigned int iir, ier = 0, lsr;
+       unsigned long flags;
+       spin_lock_irqsave(&up->port.lock, flags);
+       /*
+        * Must disable interrupts or else we risk racing with the interrupt
+        * based handler.
+        */
+       if (up->port.irq) {
+               ier = serial_in(up, UART_IER);
+               serial_out(up, UART_IER, 0);
+       }
+       iir = serial_in(up, UART_IIR);
+       /*
+        * This should be a safe test for anyone who doesn't trust the
+        * IIR bits on their UART, but it's specifically designed for
+        * the "Diva" UART used on the management processor on many HP
+        * ia64 and parisc boxes.
+        */
+       lsr = serial_in(up, UART_LSR);
+       up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+       if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) &&
+           (!uart_circ_empty(&up->port.state->xmit) || up->port.x_char) &&
+           (lsr & UART_LSR_THRE)) {
+               iir &= ~(UART_IIR_ID | UART_IIR_NO_INT);
+               iir |= UART_IIR_THRI;
+       }
+       if (!(iir & UART_IIR_NO_INT))
+               serial8250_tx_chars(up);
+       if (up->port.irq)
+               serial_out(up, UART_IER, ier);
+       spin_unlock_irqrestore(&up->port.lock, flags);
+       /* Standard timer interval plus 0.2s to keep the port running */
+       mod_timer(&up->timer,
+               jiffies + uart_poll_timeout(&up->port) + HZ / 5);
+ }
+ static unsigned int serial8250_tx_empty(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned long flags;
+       unsigned int lsr;
+       spin_lock_irqsave(&port->lock, flags);
+       lsr = serial_port_in(port, UART_LSR);
+       up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+       spin_unlock_irqrestore(&port->lock, flags);
+       return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0;
+ }
+ static unsigned int serial8250_get_mctrl(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned int status;
+       unsigned int ret;
+       status = serial8250_modem_status(up);
+       ret = 0;
+       if (status & UART_MSR_DCD)
+               ret |= TIOCM_CAR;
+       if (status & UART_MSR_RI)
+               ret |= TIOCM_RNG;
+       if (status & UART_MSR_DSR)
+               ret |= TIOCM_DSR;
+       if (status & UART_MSR_CTS)
+               ret |= TIOCM_CTS;
+       return ret;
+ }
+ static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned char mcr = 0;
+       if (mctrl & TIOCM_RTS)
+               mcr |= UART_MCR_RTS;
+       if (mctrl & TIOCM_DTR)
+               mcr |= UART_MCR_DTR;
+       if (mctrl & TIOCM_OUT1)
+               mcr |= UART_MCR_OUT1;
+       if (mctrl & TIOCM_OUT2)
+               mcr |= UART_MCR_OUT2;
+       if (mctrl & TIOCM_LOOP)
+               mcr |= UART_MCR_LOOP;
+       mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr;
+       serial_port_out(port, UART_MCR, mcr);
+ }
+ static void serial8250_break_ctl(struct uart_port *port, int break_state)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned long flags;
+       spin_lock_irqsave(&port->lock, flags);
+       if (break_state == -1)
+               up->lcr |= UART_LCR_SBC;
+       else
+               up->lcr &= ~UART_LCR_SBC;
+       serial_port_out(port, UART_LCR, up->lcr);
+       spin_unlock_irqrestore(&port->lock, flags);
+ }
+ /*
+  *    Wait for transmitter & holding register to empty
+  */
+ static void wait_for_xmitr(struct uart_8250_port *up, int bits)
+ {
+       unsigned int status, tmout = 10000;
+       /* Wait up to 10ms for the character(s) to be sent. */
+       for (;;) {
+               status = serial_in(up, UART_LSR);
+               up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
+               if ((status & bits) == bits)
+                       break;
+               if (--tmout == 0)
+                       break;
+               udelay(1);
+       }
+       /* Wait up to 1s for flow control if necessary */
+       if (up->port.flags & UPF_CONS_FLOW) {
+               unsigned int tmout;
+               for (tmout = 1000000; tmout; tmout--) {
+                       unsigned int msr = serial_in(up, UART_MSR);
+                       up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
+                       if (msr & UART_MSR_CTS)
+                               break;
+                       udelay(1);
+                       touch_nmi_watchdog();
+               }
+       }
+ }
+ #ifdef CONFIG_CONSOLE_POLL
+ /*
+  * Console polling routines for writing and reading from the uart while
+  * in an interrupt or debug context.
+  */
+ static int serial8250_get_poll_char(struct uart_port *port)
+ {
+       unsigned char lsr = serial_port_in(port, UART_LSR);
+       if (!(lsr & UART_LSR_DR))
+               return NO_POLL_CHAR;
+       return serial_port_in(port, UART_RX);
+ }
+ static void serial8250_put_poll_char(struct uart_port *port,
+                        unsigned char c)
+ {
+       unsigned int ier;
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       /*
+        *      First save the IER then disable the interrupts
+        */
+       ier = serial_port_in(port, UART_IER);
+       if (up->capabilities & UART_CAP_UUE)
+               serial_port_out(port, UART_IER, UART_IER_UUE);
+       else
+               serial_port_out(port, UART_IER, 0);
+       wait_for_xmitr(up, BOTH_EMPTY);
+       /*
+        *      Send the character out.
+        *      If a LF, also do CR...
+        */
+       serial_port_out(port, UART_TX, c);
+       if (c == 10) {
+               wait_for_xmitr(up, BOTH_EMPTY);
+               serial_port_out(port, UART_TX, 13);
+       }
+       /*
+        *      Finally, wait for transmitter to become empty
+        *      and restore the IER
+        */
+       wait_for_xmitr(up, BOTH_EMPTY);
+       serial_port_out(port, UART_IER, ier);
+ }
+ #endif /* CONFIG_CONSOLE_POLL */
+ static int serial8250_startup(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned long flags;
+       unsigned char lsr, iir;
+       int retval;
+       if (port->type == PORT_8250_CIR)
+               return -ENODEV;
+       if (!port->fifosize)
+               port->fifosize = uart_config[port->type].fifo_size;
+       if (!up->tx_loadsz)
+               up->tx_loadsz = uart_config[port->type].tx_loadsz;
+       if (!up->capabilities)
+               up->capabilities = uart_config[port->type].flags;
+       up->mcr = 0;
+       if (port->iotype != up->cur_iotype)
+               set_io_from_upio(port);
+       if (port->type == PORT_16C950) {
+               /* Wake up and initialize UART */
+               up->acr = 0;
+               serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+               serial_port_out(port, UART_EFR, UART_EFR_ECB);
+               serial_port_out(port, UART_IER, 0);
+               serial_port_out(port, UART_LCR, 0);
+               serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
+               serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+               serial_port_out(port, UART_EFR, UART_EFR_ECB);
+               serial_port_out(port, UART_LCR, 0);
+       }
+ #ifdef CONFIG_SERIAL_8250_RSA
+       /*
+        * If this is an RSA port, see if we can kick it up to the
+        * higher speed clock.
+        */
+       enable_rsa(up);
+ #endif
+       /*
+        * Clear the FIFO buffers and disable them.
+        * (they will be reenabled in set_termios())
+        */
+       serial8250_clear_fifos(up);
+       /*
+        * Clear the interrupt registers.
+        */
+       serial_port_in(port, UART_LSR);
+       serial_port_in(port, UART_RX);
+       serial_port_in(port, UART_IIR);
+       serial_port_in(port, UART_MSR);
+       /*
+        * At this point, there's no way the LSR could still be 0xff;
+        * if it is, then bail out, because there's likely no UART
+        * here.
+        */
+       if (!(port->flags & UPF_BUGGY_UART) &&
+           (serial_port_in(port, UART_LSR) == 0xff)) {
+               printk_ratelimited(KERN_INFO "ttyS%d: LSR safety check engaged!\n",
+                                  serial_index(port));
+               return -ENODEV;
+       }
+       /*
+        * For a XR16C850, we need to set the trigger levels
+        */
+       if (port->type == PORT_16850) {
+               unsigned char fctr;
+               serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+               fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
+               serial_port_out(port, UART_FCTR,
+                               fctr | UART_FCTR_TRGD | UART_FCTR_RX);
+               serial_port_out(port, UART_TRG, UART_TRG_96);
+               serial_port_out(port, UART_FCTR,
+                               fctr | UART_FCTR_TRGD | UART_FCTR_TX);
+               serial_port_out(port, UART_TRG, UART_TRG_96);
+               serial_port_out(port, UART_LCR, 0);
+       }
+       if (port->irq) {
+               unsigned char iir1;
+               /*
+                * Test for UARTs that do not reassert THRE when the
+                * transmitter is idle and the interrupt has already
+                * been cleared.  Real 16550s should always reassert
+                * this interrupt whenever the transmitter is idle and
+                * the interrupt is enabled.  Delays are necessary to
+                * allow register changes to become visible.
+                */
+               spin_lock_irqsave(&port->lock, flags);
+               if (up->port.irqflags & IRQF_SHARED)
+                       disable_irq_nosync(port->irq);
+               wait_for_xmitr(up, UART_LSR_THRE);
+               serial_port_out_sync(port, UART_IER, UART_IER_THRI);
+               udelay(1); /* allow THRE to set */
+               iir1 = serial_port_in(port, UART_IIR);
+               serial_port_out(port, UART_IER, 0);
+               serial_port_out_sync(port, UART_IER, UART_IER_THRI);
+               udelay(1); /* allow a working UART time to re-assert THRE */
+               iir = serial_port_in(port, UART_IIR);
+               serial_port_out(port, UART_IER, 0);
+               if (port->irqflags & IRQF_SHARED)
+                       enable_irq(port->irq);
+               spin_unlock_irqrestore(&port->lock, flags);
+               /*
+                * If the interrupt is not reasserted, or we otherwise
+                * don't trust the iir, setup a timer to kick the UART
+                * on a regular basis.
+                */
+               if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) ||
+                   up->port.flags & UPF_BUG_THRE) {
+                       up->bugs |= UART_BUG_THRE;
+                       pr_debug("ttyS%d - using backup timer\n",
+                                serial_index(port));
+               }
+       }
+       /*
+        * The above check will only give an accurate result the first time
+        * the port is opened so this value needs to be preserved.
+        */
+       if (up->bugs & UART_BUG_THRE) {
+               up->timer.function = serial8250_backup_timeout;
+               up->timer.data = (unsigned long)up;
+               mod_timer(&up->timer, jiffies +
+                       uart_poll_timeout(port) + HZ / 5);
+       }
+       /*
+        * If the "interrupt" for this port doesn't correspond with any
+        * hardware interrupt, we use a timer-based system.  The original
+        * driver used to do this with IRQ0.
+        */
+       if (!port->irq) {
+               up->timer.data = (unsigned long)up;
+               mod_timer(&up->timer, jiffies + uart_poll_timeout(port));
+       } else {
+               retval = serial_link_irq_chain(up);
+               if (retval)
+                       return retval;
+       }
+       /*
+        * Now, initialize the UART
+        */
+       serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+       spin_lock_irqsave(&port->lock, flags);
+       if (up->port.flags & UPF_FOURPORT) {
+               if (!up->port.irq)
+                       up->port.mctrl |= TIOCM_OUT1;
+       } else
+               /*
+                * Most PC uarts need OUT2 raised to enable interrupts.
+                */
+               if (port->irq)
+                       up->port.mctrl |= TIOCM_OUT2;
+       serial8250_set_mctrl(port, port->mctrl);
+       /* Serial over Lan (SoL) hack:
+          Intel 8257x Gigabit ethernet chips have a
+          16550 emulation, to be used for Serial Over Lan.
+          Those chips take a longer time than a normal
+          serial device to signalize that a transmission
+          data was queued. Due to that, the above test generally
+          fails. One solution would be to delay the reading of
+          iir. However, this is not reliable, since the timeout
+          is variable. So, let's just don't test if we receive
+          TX irq. This way, we'll never enable UART_BUG_TXEN.
+        */
+       if (skip_txen_test || up->port.flags & UPF_NO_TXEN_TEST)
+               goto dont_test_tx_en;
+       /*
+        * Do a quick test to see if we receive an
+        * interrupt when we enable the TX irq.
+        */
+       serial_port_out(port, UART_IER, UART_IER_THRI);
+       lsr = serial_port_in(port, UART_LSR);
+       iir = serial_port_in(port, UART_IIR);
+       serial_port_out(port, UART_IER, 0);
+       if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) {
+               if (!(up->bugs & UART_BUG_TXEN)) {
+                       up->bugs |= UART_BUG_TXEN;
+                       pr_debug("ttyS%d - enabling bad tx status workarounds\n",
+                                serial_index(port));
+               }
+       } else {
+               up->bugs &= ~UART_BUG_TXEN;
+       }
+ dont_test_tx_en:
+       spin_unlock_irqrestore(&port->lock, flags);
+       /*
+        * Clear the interrupt registers again for luck, and clear the
+        * saved flags to avoid getting false values from polling
+        * routines or the previous session.
+        */
+       serial_port_in(port, UART_LSR);
+       serial_port_in(port, UART_RX);
+       serial_port_in(port, UART_IIR);
+       serial_port_in(port, UART_MSR);
+       up->lsr_saved_flags = 0;
+       up->msr_saved_flags = 0;
+       /*
+        * Request DMA channels for both RX and TX.
+        */
+       if (up->dma) {
+               retval = serial8250_request_dma(up);
+               if (retval) {
+                       pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
+                                           serial_index(port));
+                       up->dma = NULL;
+               }
+       }
+       /*
+        * Finally, enable interrupts.  Note: Modem status interrupts
+        * are set via set_termios(), which will be occurring imminently
+        * anyway, so we don't enable them here.
+        */
+       up->ier = UART_IER_RLSI | UART_IER_RDI;
+       serial_port_out(port, UART_IER, up->ier);
+       if (port->flags & UPF_FOURPORT) {
+               unsigned int icp;
+               /*
+                * Enable interrupts on the AST Fourport board
+                */
+               icp = (port->iobase & 0xfe0) | 0x01f;
+               outb_p(0x80, icp);
+               inb_p(icp);
+       }
+       return 0;
+ }
+ static void serial8250_shutdown(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned long flags;
+       /*
+        * Disable interrupts from this port
+        */
+       up->ier = 0;
+       serial_port_out(port, UART_IER, 0);
+       if (up->dma)
+               serial8250_release_dma(up);
+       spin_lock_irqsave(&port->lock, flags);
+       if (port->flags & UPF_FOURPORT) {
+               /* reset interrupts on the AST Fourport board */
+               inb((port->iobase & 0xfe0) | 0x1f);
+               port->mctrl |= TIOCM_OUT1;
+       } else
+               port->mctrl &= ~TIOCM_OUT2;
+       serial8250_set_mctrl(port, port->mctrl);
+       spin_unlock_irqrestore(&port->lock, flags);
+       /*
+        * Disable break condition and FIFOs
+        */
+       serial_port_out(port, UART_LCR,
+                       serial_port_in(port, UART_LCR) & ~UART_LCR_SBC);
+       serial8250_clear_fifos(up);
+ #ifdef CONFIG_SERIAL_8250_RSA
+       /*
+        * Reset the RSA board back to 115kbps compat mode.
+        */
+       disable_rsa(up);
+ #endif
+       /*
+        * Read data port to reset things, and then unlink from
+        * the IRQ chain.
+        */
+       serial_port_in(port, UART_RX);
+       del_timer_sync(&up->timer);
+       up->timer.function = serial8250_timeout;
+       if (port->irq)
+               serial_unlink_irq_chain(up);
+ }
+ static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
+ {
+       unsigned int quot;
+       /*
+        * Handle magic divisors for baud rates above baud_base on
+        * SMSC SuperIO chips.
+        */
+       if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+           baud == (port->uartclk/4))
+               quot = 0x8001;
+       else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+                baud == (port->uartclk/8))
+               quot = 0x8002;
+       else
+               quot = uart_get_divisor(port, baud);
+       return quot;
+ }
+ void
+ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
+                         struct ktermios *old)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       unsigned char cval, fcr = 0;
+       unsigned long flags;
+       unsigned int baud, quot;
+       int fifo_bug = 0;
+       switch (termios->c_cflag & CSIZE) {
+       case CS5:
+               cval = UART_LCR_WLEN5;
+               break;
+       case CS6:
+               cval = UART_LCR_WLEN6;
+               break;
+       case CS7:
+               cval = UART_LCR_WLEN7;
+               break;
+       default:
+       case CS8:
+               cval = UART_LCR_WLEN8;
+               break;
+       }
+       if (termios->c_cflag & CSTOPB)
+               cval |= UART_LCR_STOP;
+       if (termios->c_cflag & PARENB) {
+               cval |= UART_LCR_PARITY;
+               if (up->bugs & UART_BUG_PARITY)
+                       fifo_bug = 1;
+       }
+       if (!(termios->c_cflag & PARODD))
+               cval |= UART_LCR_EPAR;
+ #ifdef CMSPAR
+       if (termios->c_cflag & CMSPAR)
+               cval |= UART_LCR_SPAR;
+ #endif
+       /*
+        * Ask the core to calculate the divisor for us.
+        */
+       baud = uart_get_baud_rate(port, termios, old,
+                                 port->uartclk / 16 / 0xffff,
+                                 port->uartclk / 16);
+       quot = serial8250_get_divisor(port, baud);
+       /*
+        * Oxford Semi 952 rev B workaround
+        */
+       if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0)
+               quot++;
+       if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
+               fcr = uart_config[port->type].fcr;
+               if (baud < 2400 || fifo_bug) {
+                       fcr &= ~UART_FCR_TRIGGER_MASK;
+                       fcr |= UART_FCR_TRIGGER_1;
+               }
+       }
+       /*
+        * MCR-based auto flow control.  When AFE is enabled, RTS will be
+        * deasserted when the receive FIFO contains more characters than
+        * the trigger, or the MCR RTS bit is cleared.  In the case where
+        * the remote UART is not using CTS auto flow control, we must
+        * have sufficient FIFO entries for the latency of the remote
+        * UART to respond.  IOW, at least 32 bytes of FIFO.
+        */
+       if (up->capabilities & UART_CAP_AFE && port->fifosize >= 32) {
+               up->mcr &= ~UART_MCR_AFE;
+               if (termios->c_cflag & CRTSCTS)
+                       up->mcr |= UART_MCR_AFE;
+       }
+       /*
+        * Ok, we're now changing the port state.  Do it with
+        * interrupts disabled.
+        */
+       spin_lock_irqsave(&port->lock, flags);
+       /*
+        * Update the per-port timeout.
+        */
+       uart_update_timeout(port, termios->c_cflag, baud);
+       port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+       if (termios->c_iflag & INPCK)
+               port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+       if (termios->c_iflag & (BRKINT | PARMRK))
+               port->read_status_mask |= UART_LSR_BI;
+       /*
+        * Characteres to ignore
+        */
+       port->ignore_status_mask = 0;
+       if (termios->c_iflag & IGNPAR)
+               port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+       if (termios->c_iflag & IGNBRK) {
+               port->ignore_status_mask |= UART_LSR_BI;
+               /*
+                * If we're ignoring parity and break indicators,
+                * ignore overruns too (for real raw support).
+                */
+               if (termios->c_iflag & IGNPAR)
+                       port->ignore_status_mask |= UART_LSR_OE;
+       }
+       /*
+        * ignore all characters if CREAD is not set
+        */
+       if ((termios->c_cflag & CREAD) == 0)
+               port->ignore_status_mask |= UART_LSR_DR;
+       /*
+        * CTS flow control flag and modem status interrupts
+        */
+       up->ier &= ~UART_IER_MSI;
+       if (!(up->bugs & UART_BUG_NOMSR) &&
+                       UART_ENABLE_MS(&up->port, termios->c_cflag))
+               up->ier |= UART_IER_MSI;
+       if (up->capabilities & UART_CAP_UUE)
+               up->ier |= UART_IER_UUE;
+       if (up->capabilities & UART_CAP_RTOIE)
+               up->ier |= UART_IER_RTOIE;
+       serial_port_out(port, UART_IER, up->ier);
+       if (up->capabilities & UART_CAP_EFR) {
+               unsigned char efr = 0;
+               /*
+                * TI16C752/Startech hardware flow control.  FIXME:
+                * - TI16C752 requires control thresholds to be set.
+                * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
+                */
+               if (termios->c_cflag & CRTSCTS)
+                       efr |= UART_EFR_CTS;
+               serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+               if (port->flags & UPF_EXAR_EFR)
+                       serial_port_out(port, UART_XR_EFR, efr);
+               else
+                       serial_port_out(port, UART_EFR, efr);
+       }
+       /* Workaround to enable 115200 baud on OMAP1510 internal ports */
+       if (is_omap1510_8250(up)) {
+               if (baud == 115200) {
+                       quot = 1;
+                       serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1);
+               } else
+                       serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0);
+       }
+       /*
+        * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2,
+        * otherwise just set DLAB
+        */
+       if (up->capabilities & UART_NATSEMI)
+               serial_port_out(port, UART_LCR, 0xe0);
+       else
+               serial_port_out(port, UART_LCR, cval | UART_LCR_DLAB);
+       serial_dl_write(up, quot);
+       /*
+        * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
+        * is written without DLAB set, this mode will be disabled.
+        */
+       if (port->type == PORT_16750)
+               serial_port_out(port, UART_FCR, fcr);
+       serial_port_out(port, UART_LCR, cval);          /* reset DLAB */
+       up->lcr = cval;                                 /* Save LCR */
+       if (port->type != PORT_16750) {
+               /* emulated UARTs (Lucent Venus 167x) need two steps */
+               if (fcr & UART_FCR_ENABLE_FIFO)
+                       serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
+               serial_port_out(port, UART_FCR, fcr);           /* set fcr */
+       }
+       serial8250_set_mctrl(port, port->mctrl);
+       spin_unlock_irqrestore(&port->lock, flags);
+       /* Don't rewrite B0 */
+       if (tty_termios_baud_rate(termios))
+               tty_termios_encode_baud_rate(termios, baud, baud);
+ }
+ EXPORT_SYMBOL(serial8250_do_set_termios);
+ static void
+ serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
+                      struct ktermios *old)
+ {
+       if (port->set_termios)
+               port->set_termios(port, termios, old);
+       else
+               serial8250_do_set_termios(port, termios, old);
+ }
+ static void
+ serial8250_set_ldisc(struct uart_port *port, int new)
+ {
+       if (new == N_PPS) {
+               port->flags |= UPF_HARDPPS_CD;
+               serial8250_enable_ms(port);
+       } else
+               port->flags &= ~UPF_HARDPPS_CD;
+ }
+ void serial8250_do_pm(struct uart_port *port, unsigned int state,
+                     unsigned int oldstate)
+ {
+       struct uart_8250_port *p =
+               container_of(port, struct uart_8250_port, port);
+       serial8250_set_sleep(p, state != 0);
+ }
+ EXPORT_SYMBOL(serial8250_do_pm);
+ static void
+ serial8250_pm(struct uart_port *port, unsigned int state,
+             unsigned int oldstate)
+ {
+       if (port->pm)
+               port->pm(port, state, oldstate);
+       else
+               serial8250_do_pm(port, state, oldstate);
+ }
+ static unsigned int serial8250_port_size(struct uart_8250_port *pt)
+ {
+       if (pt->port.iotype == UPIO_AU)
+               return 0x1000;
+       if (is_omap1_8250(pt))
+               return 0x16 << pt->port.regshift;
+       return 8 << pt->port.regshift;
+ }
+ /*
+  * Resource handling.
+  */
+ static int serial8250_request_std_resource(struct uart_8250_port *up)
+ {
+       unsigned int size = serial8250_port_size(up);
+       struct uart_port *port = &up->port;
+       int ret = 0;
+       switch (port->iotype) {
+       case UPIO_AU:
+       case UPIO_TSI:
+       case UPIO_MEM32:
+       case UPIO_MEM:
+               if (!port->mapbase)
+                       break;
+               if (!request_mem_region(port->mapbase, size, "serial")) {
+                       ret = -EBUSY;
+                       break;
+               }
+               if (port->flags & UPF_IOREMAP) {
+                       port->membase = ioremap_nocache(port->mapbase, size);
+                       if (!port->membase) {
+                               release_mem_region(port->mapbase, size);
+                               ret = -ENOMEM;
+                       }
+               }
+               break;
+       case UPIO_HUB6:
+       case UPIO_PORT:
+               if (!request_region(port->iobase, size, "serial"))
+                       ret = -EBUSY;
+               break;
+       }
+       return ret;
+ }
+ static void serial8250_release_std_resource(struct uart_8250_port *up)
+ {
+       unsigned int size = serial8250_port_size(up);
+       struct uart_port *port = &up->port;
+       switch (port->iotype) {
+       case UPIO_AU:
+       case UPIO_TSI:
+       case UPIO_MEM32:
+       case UPIO_MEM:
+               if (!port->mapbase)
+                       break;
+               if (port->flags & UPF_IOREMAP) {
+                       iounmap(port->membase);
+                       port->membase = NULL;
+               }
+               release_mem_region(port->mapbase, size);
+               break;
+       case UPIO_HUB6:
+       case UPIO_PORT:
+               release_region(port->iobase, size);
+               break;
+       }
+ }
+ static int serial8250_request_rsa_resource(struct uart_8250_port *up)
+ {
+       unsigned long start = UART_RSA_BASE << up->port.regshift;
+       unsigned int size = 8 << up->port.regshift;
+       struct uart_port *port = &up->port;
+       int ret = -EINVAL;
+       switch (port->iotype) {
+       case UPIO_HUB6:
+       case UPIO_PORT:
+               start += port->iobase;
+               if (request_region(start, size, "serial-rsa"))
+                       ret = 0;
+               else
+                       ret = -EBUSY;
+               break;
+       }
+       return ret;
+ }
+ static void serial8250_release_rsa_resource(struct uart_8250_port *up)
+ {
+       unsigned long offset = UART_RSA_BASE << up->port.regshift;
+       unsigned int size = 8 << up->port.regshift;
+       struct uart_port *port = &up->port;
+       switch (port->iotype) {
+       case UPIO_HUB6:
+       case UPIO_PORT:
+               release_region(port->iobase + offset, size);
+               break;
+       }
+ }
+ static void serial8250_release_port(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       serial8250_release_std_resource(up);
+       if (port->type == PORT_RSA)
+               serial8250_release_rsa_resource(up);
+ }
+ static int serial8250_request_port(struct uart_port *port)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       int ret;
+       if (port->type == PORT_8250_CIR)
+               return -ENODEV;
+       ret = serial8250_request_std_resource(up);
+       if (ret == 0 && port->type == PORT_RSA) {
+               ret = serial8250_request_rsa_resource(up);
+               if (ret < 0)
+                       serial8250_release_std_resource(up);
+       }
+       return ret;
+ }
+ static void serial8250_config_port(struct uart_port *port, int flags)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       int probeflags = PROBE_ANY;
+       int ret;
+       if (port->type == PORT_8250_CIR)
+               return;
+       /*
+        * Find the region that we can probe for.  This in turn
+        * tells us whether we can probe for the type of port.
+        */
+       ret = serial8250_request_std_resource(up);
+       if (ret < 0)
+               return;
+       ret = serial8250_request_rsa_resource(up);
+       if (ret < 0)
+               probeflags &= ~PROBE_RSA;
+       if (port->iotype != up->cur_iotype)
+               set_io_from_upio(port);
+       if (flags & UART_CONFIG_TYPE)
+               autoconfig(up, probeflags);
+       /* if access method is AU, it is a 16550 with a quirk */
+       if (port->type == PORT_16550A && port->iotype == UPIO_AU)
+               up->bugs |= UART_BUG_NOMSR;
+       if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
+               autoconfig_irq(up);
+       if (port->type != PORT_RSA && probeflags & PROBE_RSA)
+               serial8250_release_rsa_resource(up);
+       if (port->type == PORT_UNKNOWN)
+               serial8250_release_std_resource(up);
+       /* Fixme: probably not the best place for this */
+       if ((port->type == PORT_XR17V35X) ||
+          (port->type == PORT_XR17D15X))
+               port->handle_irq = exar_handle_irq;
+ }
+ static int
+ serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
+ {
+       if (ser->irq >= nr_irqs || ser->irq < 0 ||
+           ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
+           ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
+           ser->type == PORT_STARTECH)
+               return -EINVAL;
+       return 0;
+ }
+ static const char *
+ serial8250_type(struct uart_port *port)
+ {
+       int type = port->type;
+       if (type >= ARRAY_SIZE(uart_config))
+               type = 0;
+       return uart_config[type].name;
+ }
+ static struct uart_ops serial8250_pops = {
+       .tx_empty       = serial8250_tx_empty,
+       .set_mctrl      = serial8250_set_mctrl,
+       .get_mctrl      = serial8250_get_mctrl,
+       .stop_tx        = serial8250_stop_tx,
+       .start_tx       = serial8250_start_tx,
+       .stop_rx        = serial8250_stop_rx,
+       .enable_ms      = serial8250_enable_ms,
+       .break_ctl      = serial8250_break_ctl,
+       .startup        = serial8250_startup,
+       .shutdown       = serial8250_shutdown,
+       .set_termios    = serial8250_set_termios,
+       .set_ldisc      = serial8250_set_ldisc,
+       .pm             = serial8250_pm,
+       .type           = serial8250_type,
+       .release_port   = serial8250_release_port,
+       .request_port   = serial8250_request_port,
+       .config_port    = serial8250_config_port,
+       .verify_port    = serial8250_verify_port,
+ #ifdef CONFIG_CONSOLE_POLL
+       .poll_get_char = serial8250_get_poll_char,
+       .poll_put_char = serial8250_put_poll_char,
+ #endif
+ };
+ static struct uart_8250_port serial8250_ports[UART_NR];
+ static void (*serial8250_isa_config)(int port, struct uart_port *up,
+       unsigned short *capabilities);
+ void serial8250_set_isa_configurator(
+       void (*v)(int port, struct uart_port *up, unsigned short *capabilities))
+ {
+       serial8250_isa_config = v;
+ }
+ EXPORT_SYMBOL(serial8250_set_isa_configurator);
+ static void __init serial8250_isa_init_ports(void)
+ {
+       struct uart_8250_port *up;
+       static int first = 1;
+       int i, irqflag = 0;
+       if (!first)
+               return;
+       first = 0;
+       if (nr_uarts > UART_NR)
+               nr_uarts = UART_NR;
 -      if (co->index >= nr_uarts)
++      for (i = 0; i < UART_NR; i++) {
+               struct uart_8250_port *up = &serial8250_ports[i];
+               struct uart_port *port = &up->port;
+               port->line = i;
+               spin_lock_init(&port->lock);
+               init_timer(&up->timer);
+               up->timer.function = serial8250_timeout;
+               up->cur_iotype = 0xFF;
+               /*
+                * ALPHA_KLUDGE_MCR needs to be killed.
+                */
+               up->mcr_mask = ~ALPHA_KLUDGE_MCR;
+               up->mcr_force = ALPHA_KLUDGE_MCR;
+               port->ops = &serial8250_pops;
+       }
+       if (share_irqs)
+               irqflag = IRQF_SHARED;
+       for (i = 0, up = serial8250_ports;
+            i < ARRAY_SIZE(old_serial_port) && i < nr_uarts;
+            i++, up++) {
+               struct uart_port *port = &up->port;
+               port->iobase   = old_serial_port[i].port;
+               port->irq      = irq_canonicalize(old_serial_port[i].irq);
+               port->irqflags = old_serial_port[i].irqflags;
+               port->uartclk  = old_serial_port[i].baud_base * 16;
+               port->flags    = old_serial_port[i].flags;
+               port->hub6     = old_serial_port[i].hub6;
+               port->membase  = old_serial_port[i].iomem_base;
+               port->iotype   = old_serial_port[i].io_type;
+               port->regshift = old_serial_port[i].iomem_reg_shift;
+               set_io_from_upio(port);
+               port->irqflags |= irqflag;
+               if (serial8250_isa_config != NULL)
+                       serial8250_isa_config(i, &up->port, &up->capabilities);
+       }
+ }
+ static void
+ serial8250_init_fixed_type_port(struct uart_8250_port *up, unsigned int type)
+ {
+       up->port.type = type;
+       if (!up->port.fifosize)
+               up->port.fifosize = uart_config[type].fifo_size;
+       if (!up->tx_loadsz)
+               up->tx_loadsz = uart_config[type].tx_loadsz;
+       if (!up->capabilities)
+               up->capabilities = uart_config[type].flags;
+ }
+ static void __init
+ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
+ {
+       int i;
+       for (i = 0; i < nr_uarts; i++) {
+               struct uart_8250_port *up = &serial8250_ports[i];
+               if (up->port.dev)
+                       continue;
+               up->port.dev = dev;
+               if (up->port.flags & UPF_FIXED_TYPE)
+                       serial8250_init_fixed_type_port(up, up->port.type);
+               uart_add_one_port(drv, &up->port);
+       }
+ }
+ #ifdef CONFIG_SERIAL_8250_CONSOLE
+ static void serial8250_console_putchar(struct uart_port *port, int ch)
+ {
+       struct uart_8250_port *up =
+               container_of(port, struct uart_8250_port, port);
+       wait_for_xmitr(up, UART_LSR_THRE);
+       serial_port_out(port, UART_TX, ch);
+ }
+ /*
+  *    Print a string to the serial port trying not to disturb
+  *    any possible real use of the port...
+  *
+  *    The console_lock must be held when we get here.
+  */
+ static void
+ serial8250_console_write(struct console *co, const char *s, unsigned int count)
+ {
+       struct uart_8250_port *up = &serial8250_ports[co->index];
+       struct uart_port *port = &up->port;
+       unsigned long flags;
+       unsigned int ier;
+       int locked = 1;
+       touch_nmi_watchdog();
+       local_irq_save(flags);
+       if (port->sysrq) {
+               /* serial8250_handle_irq() already took the lock */
+               locked = 0;
+       } else if (oops_in_progress) {
+               locked = spin_trylock(&port->lock);
+       } else
+               spin_lock(&port->lock);
+       /*
+        *      First save the IER then disable the interrupts
+        */
+       ier = serial_port_in(port, UART_IER);
+       if (up->capabilities & UART_CAP_UUE)
+               serial_port_out(port, UART_IER, UART_IER_UUE);
+       else
+               serial_port_out(port, UART_IER, 0);
+       uart_console_write(port, s, count, serial8250_console_putchar);
+       /*
+        *      Finally, wait for transmitter to become empty
+        *      and restore the IER
+        */
+       wait_for_xmitr(up, BOTH_EMPTY);
+       serial_port_out(port, UART_IER, ier);
+       /*
+        *      The receive handling will happen properly because the
+        *      receive ready bit will still be set; it is not cleared
+        *      on read.  However, modem control will not, we must
+        *      call it if we have saved something in the saved flags
+        *      while processing with interrupts off.
+        */
+       if (up->msr_saved_flags)
+               serial8250_modem_status(up);
+       if (locked)
+               spin_unlock(&port->lock);
+       local_irq_restore(flags);
+ }
+ static int __init serial8250_console_setup(struct console *co, char *options)
+ {
+       struct uart_port *port;
+       int baud = 9600;
+       int bits = 8;
+       int parity = 'n';
+       int flow = 'n';
+       /*
+        * Check whether an invalid uart number has been specified, and
+        * if so, search for the first available port that does have
+        * console support.
+        */
 -      for (line = 0; line < nr_uarts; line++) {
++      if (co->index >= UART_NR)
+               co->index = 0;
+       port = &serial8250_ports[co->index].port;
+       if (!port->iobase && !port->membase)
+               return -ENODEV;
+       if (options)
+               uart_parse_options(options, &baud, &parity, &bits, &flow);
+       return uart_set_options(port, co, baud, parity, bits, flow);
+ }
+ static int serial8250_console_early_setup(void)
+ {
+       return serial8250_find_port_for_earlycon();
+ }
+ static struct console serial8250_console = {
+       .name           = "ttyS",
+       .write          = serial8250_console_write,
+       .device         = uart_console_device,
+       .setup          = serial8250_console_setup,
+       .early_setup    = serial8250_console_early_setup,
+       .flags          = CON_PRINTBUFFER | CON_ANYTIME,
+       .index          = -1,
+       .data           = &serial8250_reg,
+ };
+ static int __init serial8250_console_init(void)
+ {
+       serial8250_isa_init_ports();
+       register_console(&serial8250_console);
+       return 0;
+ }
+ console_initcall(serial8250_console_init);
+ int serial8250_find_port(struct uart_port *p)
+ {
+       int line;
+       struct uart_port *port;
 -      for (i = 0; i < nr_uarts; i++) {
++      for (line = 0; line < UART_NR; line++) {
+               port = &serial8250_ports[line].port;
+               if (uart_match_port(p, port))
+                       return line;
+       }
+       return -ENODEV;
+ }
+ #define SERIAL8250_CONSOLE    &serial8250_console
+ #else
+ #define SERIAL8250_CONSOLE    NULL
+ #endif
+ static struct uart_driver serial8250_reg = {
+       .owner                  = THIS_MODULE,
+       .driver_name            = "serial",
+       .dev_name               = "ttyS",
+       .major                  = TTY_MAJOR,
+       .minor                  = 64,
+       .cons                   = SERIAL8250_CONSOLE,
+ };
+ /*
+  * early_serial_setup - early registration for 8250 ports
+  *
+  * Setup an 8250 port structure prior to console initialisation.  Use
+  * after console initialisation will cause undefined behaviour.
+  */
+ int __init early_serial_setup(struct uart_port *port)
+ {
+       struct uart_port *p;
+       if (port->line >= ARRAY_SIZE(serial8250_ports))
+               return -ENODEV;
+       serial8250_isa_init_ports();
+       p = &serial8250_ports[port->line].port;
+       p->iobase       = port->iobase;
+       p->membase      = port->membase;
+       p->irq          = port->irq;
+       p->irqflags     = port->irqflags;
+       p->uartclk      = port->uartclk;
+       p->fifosize     = port->fifosize;
+       p->regshift     = port->regshift;
+       p->iotype       = port->iotype;
+       p->flags        = port->flags;
+       p->mapbase      = port->mapbase;
+       p->private_data = port->private_data;
+       p->type         = port->type;
+       p->line         = port->line;
+       set_io_from_upio(p);
+       if (port->serial_in)
+               p->serial_in = port->serial_in;
+       if (port->serial_out)
+               p->serial_out = port->serial_out;
+       if (port->handle_irq)
+               p->handle_irq = port->handle_irq;
+       else
+               p->handle_irq = serial8250_default_handle_irq;
+       return 0;
+ }
+ /**
+  *    serial8250_suspend_port - suspend one serial port
+  *    @line:  serial line number
+  *
+  *    Suspend one serial port.
+  */
+ void serial8250_suspend_port(int line)
+ {
+       uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
+ }
+ /**
+  *    serial8250_resume_port - resume one serial port
+  *    @line:  serial line number
+  *
+  *    Resume one serial port.
+  */
+ void serial8250_resume_port(int line)
+ {
+       struct uart_8250_port *up = &serial8250_ports[line];
+       struct uart_port *port = &up->port;
+       if (up->capabilities & UART_NATSEMI) {
+               /* Ensure it's still in high speed mode */
+               serial_port_out(port, UART_LCR, 0xE0);
+               ns16550a_goto_highspeed(up);
+               serial_port_out(port, UART_LCR, 0);
+               port->uartclk = 921600*16;
+       }
+       uart_resume_port(&serial8250_reg, port);
+ }
+ /*
+  * Register a set of serial devices attached to a platform device.  The
+  * list is terminated with a zero flags entry, which means we expect
+  * all entries to have at least UPF_BOOT_AUTOCONF set.
+  */
+ static int serial8250_probe(struct platform_device *dev)
+ {
+       struct plat_serial8250_port *p = dev->dev.platform_data;
+       struct uart_8250_port uart;
+       int ret, i, irqflag = 0;
+       memset(&uart, 0, sizeof(uart));
+       if (share_irqs)
+               irqflag = IRQF_SHARED;
+       for (i = 0; p && p->flags != 0; p++, i++) {
+               uart.port.iobase        = p->iobase;
+               uart.port.membase       = p->membase;
+               uart.port.irq           = p->irq;
+               uart.port.irqflags      = p->irqflags;
+               uart.port.uartclk       = p->uartclk;
+               uart.port.regshift      = p->regshift;
+               uart.port.iotype        = p->iotype;
+               uart.port.flags         = p->flags;
+               uart.port.mapbase       = p->mapbase;
+               uart.port.hub6          = p->hub6;
+               uart.port.private_data  = p->private_data;
+               uart.port.type          = p->type;
+               uart.port.serial_in     = p->serial_in;
+               uart.port.serial_out    = p->serial_out;
+               uart.port.handle_irq    = p->handle_irq;
+               uart.port.handle_break  = p->handle_break;
+               uart.port.set_termios   = p->set_termios;
+               uart.port.pm            = p->pm;
+               uart.port.dev           = &dev->dev;
+               uart.port.irqflags      |= irqflag;
+               ret = serial8250_register_8250_port(&uart);
+               if (ret < 0) {
+                       dev_err(&dev->dev, "unable to register port at index %d "
+                               "(IO%lx MEM%llx IRQ%d): %d\n", i,
+                               p->iobase, (unsigned long long)p->mapbase,
+                               p->irq, ret);
+               }
+       }
+       return 0;
+ }
+ /*
+  * Remove serial ports registered against a platform device.
+  */
+ static int serial8250_remove(struct platform_device *dev)
+ {
+       int i;
 -      for (i = 0; i < nr_uarts; i++)
++      for (i = 0; i < UART_NR; i++) {
+               struct uart_8250_port *up = &serial8250_ports[i];
+               if (up->port.dev == &dev->dev)
+                       serial8250_unregister_port(i);
+       }
+       return 0;
+ }
+ static int serial8250_suspend(struct platform_device *dev, pm_message_t state)
+ {
+       int i;
+       for (i = 0; i < UART_NR; i++) {
+               struct uart_8250_port *up = &serial8250_ports[i];
+               if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev)
+                       uart_suspend_port(&serial8250_reg, &up->port);
+       }
+       return 0;
+ }
+ static int serial8250_resume(struct platform_device *dev)
+ {
+       int i;
+       for (i = 0; i < UART_NR; i++) {
+               struct uart_8250_port *up = &serial8250_ports[i];
+               if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev)
+                       serial8250_resume_port(i);
+       }
+       return 0;
+ }
+ static struct platform_driver serial8250_isa_driver = {
+       .probe          = serial8250_probe,
+       .remove         = serial8250_remove,
+       .suspend        = serial8250_suspend,
+       .resume         = serial8250_resume,
+       .driver         = {
+               .name   = "serial8250",
+               .owner  = THIS_MODULE,
+       },
+ };
+ /*
+  * This "device" covers _all_ ISA 8250-compatible serial devices listed
+  * in the table in include/asm/serial.h
+  */
+ static struct platform_device *serial8250_isa_devs;
+ /*
+  * serial8250_register_8250_port and serial8250_unregister_port allows for
+  * 16x50 serial ports to be configured at run-time, to support PCMCIA
+  * modems and PCI multiport cards.
+  */
+ static DEFINE_MUTEX(serial_mutex);
+ static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *port)
+ {
+       int i;
+       /*
+        * First, find a port entry which matches.
+        */
 -      for (i = 0; i < nr_uarts; i++)
++      for (i = 0; i < UART_NR; i++)
+               if (uart_match_port(&serial8250_ports[i].port, port))
+                       return &serial8250_ports[i];
+       /*
+        * We didn't find a matching entry, so look for the first
+        * free entry.  We look for one which hasn't been previously
+        * used (indicated by zero iobase).
+        */
 -      for (i = 0; i < nr_uarts; i++)
++      for (i = 0; i < UART_NR; i++)
+               if (serial8250_ports[i].port.type == PORT_UNKNOWN &&
+                   serial8250_ports[i].port.iobase == 0)
+                       return &serial8250_ports[i];
+       /*
+        * 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++)
+               if (serial8250_ports[i].port.type == PORT_UNKNOWN)
+                       return &serial8250_ports[i];
+       return NULL;
+ }
+ /**
+  *    serial8250_register_8250_port - register a serial port
+  *    @up: serial port template
+  *
+  *    Configure the serial port specified by the request. If the
+  *    port exists and is in use, it is hung up and unregistered
+  *    first.
+  *
+  *    The port is then probed and if necessary the IRQ is autodetected
+  *    If this fails an error is returned.
+  *
+  *    On success the port is ready to use and the line number is returned.
+  */
+ int serial8250_register_8250_port(struct uart_8250_port *up)
+ {
+       struct uart_8250_port *uart;
+       int ret = -ENOSPC;
+       if (up->port.uartclk == 0)
+               return -EINVAL;
+       mutex_lock(&serial_mutex);
+       uart = serial8250_find_match_or_unused(&up->port);
+       if (uart && uart->port.type != PORT_8250_CIR) {
+               if (uart->port.dev)
+                       uart_remove_one_port(&serial8250_reg, &uart->port);
+               uart->port.iobase       = up->port.iobase;
+               uart->port.membase      = up->port.membase;
+               uart->port.irq          = up->port.irq;
+               uart->port.irqflags     = up->port.irqflags;
+               uart->port.uartclk      = up->port.uartclk;
+               uart->port.fifosize     = up->port.fifosize;
+               uart->port.regshift     = up->port.regshift;
+               uart->port.iotype       = up->port.iotype;
+               uart->port.flags        = up->port.flags | UPF_BOOT_AUTOCONF;
+               uart->bugs              = up->bugs;
+               uart->port.mapbase      = up->port.mapbase;
+               uart->port.private_data = up->port.private_data;
+               uart->port.fifosize     = up->port.fifosize;
+               uart->tx_loadsz         = up->tx_loadsz;
+               uart->capabilities      = up->capabilities;
++              /* Take tx_loadsz from fifosize if it wasn't set separately */
++              if (uart->port.fifosize && !uart->tx_loadsz)
++                      uart->tx_loadsz = uart->port.fifosize;
++
+               if (up->port.dev)
+                       uart->port.dev = up->port.dev;
+               if (up->port.flags & UPF_FIXED_TYPE)
+                       serial8250_init_fixed_type_port(uart, up->port.type);
+               set_io_from_upio(&uart->port);
+               /* Possibly override default I/O functions.  */
+               if (up->port.serial_in)
+                       uart->port.serial_in = up->port.serial_in;
+               if (up->port.serial_out)
+                       uart->port.serial_out = up->port.serial_out;
+               if (up->port.handle_irq)
+                       uart->port.handle_irq = up->port.handle_irq;
+               /*  Possibly override set_termios call */
+               if (up->port.set_termios)
+                       uart->port.set_termios = up->port.set_termios;
+               if (up->port.pm)
+                       uart->port.pm = up->port.pm;
+               if (up->port.handle_break)
+                       uart->port.handle_break = up->port.handle_break;
+               if (up->dl_read)
+                       uart->dl_read = up->dl_read;
+               if (up->dl_write)
+                       uart->dl_write = up->dl_write;
+               if (up->dma)
+                       uart->dma = up->dma;
+               if (serial8250_isa_config != NULL)
+                       serial8250_isa_config(0, &uart->port,
+                                       &uart->capabilities);
+               ret = uart_add_one_port(&serial8250_reg, &uart->port);
+               if (ret == 0)
+                       ret = uart->port.line;
+       }
+       mutex_unlock(&serial_mutex);
+       return ret;
+ }
+ EXPORT_SYMBOL(serial8250_register_8250_port);
+ /**
+  *    serial8250_unregister_port - remove a 16x50 serial port at runtime
+  *    @line: serial line number
+  *
+  *    Remove one serial port.  This may not be called from interrupt
+  *    context.  We hand the port back to the our control.
+  */
+ void serial8250_unregister_port(int line)
+ {
+       struct uart_8250_port *uart = &serial8250_ports[line];
+       mutex_lock(&serial_mutex);
+       uart_remove_one_port(&serial8250_reg, &uart->port);
+       if (serial8250_isa_devs) {
+               uart->port.flags &= ~UPF_BOOT_AUTOCONF;
+               uart->port.type = PORT_UNKNOWN;
+               uart->port.dev = &serial8250_isa_devs->dev;
+               uart->capabilities = uart_config[uart->port.type].flags;
+               uart_add_one_port(&serial8250_reg, &uart->port);
+       } else {
+               uart->port.dev = NULL;
+       }
+       mutex_unlock(&serial_mutex);
+ }
+ EXPORT_SYMBOL(serial8250_unregister_port);
+ static int __init serial8250_init(void)
+ {
+       int ret;
+       serial8250_isa_init_ports();
+       printk(KERN_INFO "Serial: 8250/16550 driver, "
+               "%d ports, IRQ sharing %sabled\n", nr_uarts,
+               share_irqs ? "en" : "dis");
+ #ifdef CONFIG_SPARC
+       ret = sunserial_register_minors(&serial8250_reg, UART_NR);
+ #else
+       serial8250_reg.nr = UART_NR;
+       ret = uart_register_driver(&serial8250_reg);
+ #endif
+       if (ret)
+               goto out;
+       ret = serial8250_pnp_init();
+       if (ret)
+               goto unreg_uart_drv;
+       serial8250_isa_devs = platform_device_alloc("serial8250",
+                                                   PLAT8250_DEV_LEGACY);
+       if (!serial8250_isa_devs) {
+               ret = -ENOMEM;
+               goto unreg_pnp;
+       }
+       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_del(serial8250_isa_devs);
+ put_dev:
+       platform_device_put(serial8250_isa_devs);
+ unreg_pnp:
+       serial8250_pnp_exit();
+ unreg_uart_drv:
+ #ifdef CONFIG_SPARC
+       sunserial_unregister_minors(&serial8250_reg, UART_NR);
+ #else
+       uart_unregister_driver(&serial8250_reg);
+ #endif
+ out:
+       return ret;
+ }
+ static void __exit serial8250_exit(void)
+ {
+       struct platform_device *isa_dev = serial8250_isa_devs;
+       /*
+        * This tells serial8250_unregister_port() not to re-register
+        * the ports (thereby making serial8250_isa_driver permanently
+        * in use.)
+        */
+       serial8250_isa_devs = NULL;
+       platform_driver_unregister(&serial8250_isa_driver);
+       platform_device_unregister(isa_dev);
+       serial8250_pnp_exit();
+ #ifdef CONFIG_SPARC
+       sunserial_unregister_minors(&serial8250_reg, UART_NR);
+ #else
+       uart_unregister_driver(&serial8250_reg);
+ #endif
+ }
+ module_init(serial8250_init);
+ module_exit(serial8250_exit);
+ EXPORT_SYMBOL(serial8250_suspend_port);
+ EXPORT_SYMBOL(serial8250_resume_port);
+ MODULE_LICENSE("GPL");
+ MODULE_DESCRIPTION("Generic 8250/16x50 serial driver");
+ 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) ")");
+ 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");
+ #endif
+ MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR);
+ #ifdef CONFIG_SERIAL_8250_DEPRECATED_OPTIONS
+ #ifndef MODULE
+ /* This module was renamed to 8250_core in 3.7.  Keep the old "8250" name
+  * working as well for the module options so we don't break people.  We
+  * need to keep the names identical and the convenient macros will happily
+  * refuse to let us do that by failing the build with redefinition errors
+  * of global variables.  So we stick them inside a dummy function to avoid
+  * those conflicts.  The options still get parsed, and the redefined
+  * MODULE_PARAM_PREFIX lets us keep the "8250." syntax alive.
+  *
+  * This is hacky.  I'm sorry.
+  */
+ static void __used s8250_options(void)
+ {
+ #undef MODULE_PARAM_PREFIX
+ #define MODULE_PARAM_PREFIX "8250_core."
+       module_param_cb(share_irqs, &param_ops_uint, &share_irqs, 0644);
+       module_param_cb(nr_uarts, &param_ops_uint, &nr_uarts, 0644);
+       module_param_cb(skip_txen_test, &param_ops_uint, &skip_txen_test, 0644);
+ #ifdef CONFIG_SERIAL_8250_RSA
+       __module_param_call(MODULE_PARAM_PREFIX, probe_rsa,
+               &param_array_ops, .arr = &__param_arr_probe_rsa,
+               0444, -1);
+ #endif
+ }
+ #else
+ MODULE_ALIAS("8250_core");
+ #endif
+ #endif
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge