Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
new file mode 100644
index 0000000..201c3b9
--- /dev/null
+++ b/drivers/serial/8250.c
@@ -0,0 +1,2632 @@
+/*
+ * linux/drivers/char/8250.c
+ *
+ * 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.
+ *
+ * $Id: 8250.c,v 1.90 2002/07/28 10:03:27 rmk Exp $
+ *
+ * A note about mapbase / membase
+ *
+ * mapbase is the physical address of the IO port.
+ * membase is an 'ioremapped' cookie.
+ */
+#include <linux/config.h>
+
+#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/mca.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/tty.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 <asm/io.h>
+#include <asm/irq.h>
+
+#include "8250.h"
+
+/*
+ * Configuration:
+ * share_irqs - whether we pass SA_SHIRQ to request_irq(). This option
+ * is unsafe when used on edge-triggered interrupts.
+ */
+unsigned int share_irqs = SERIAL8250_SHARE_IRQS;
+
+/*
+ * 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 256
+
+/*
+ * We default to IRQ0 for the "no irq" hack. Some
+ * machine types want others as well - they're free
+ * to redefine this in their header file.
+ */
+#define is_real_interrupt(irq) ((irq) != 0)
+
+/*
+ * This converts from our new CONFIG_ symbols to the symbols
+ * that asm/serial.h expects. You _NEED_ to comment out the
+ * linux/config.h include contained inside asm/serial.h for
+ * this to work.
+ */
+#undef CONFIG_SERIAL_MANY_PORTS
+#undef CONFIG_SERIAL_DETECT_IRQ
+#undef CONFIG_SERIAL_MULTIPORT
+#undef CONFIG_HUB6
+
+#ifdef CONFIG_SERIAL_8250_DETECT_IRQ
+#define CONFIG_SERIAL_DETECT_IRQ 1
+#endif
+#ifdef CONFIG_SERIAL_8250_MULTIPORT
+#define CONFIG_SERIAL_MULTIPORT 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 struct old_serial_port old_serial_port[] = {
+ SERIAL_PORT_DFNS /* defined in asm/serial.h */
+};
+
+#define UART_NR (ARRAY_SIZE(old_serial_port) + 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 uart_8250_port {
+ struct uart_port port;
+ struct timer_list timer; /* "no irq" timer */
+ struct list_head list; /* ports on this IRQ */
+ unsigned int capabilities; /* port capabilities */
+ unsigned int tx_loadsz; /* transmit fifo load size */
+ unsigned short rev;
+ unsigned char acr;
+ unsigned char ier;
+ unsigned char lcr;
+ unsigned char mcr;
+ unsigned char mcr_mask; /* mask of user bits */
+ unsigned char mcr_force; /* mask of forced bits */
+ unsigned char lsr_break_flag;
+
+ /*
+ * We provide a per-port pm hook.
+ */
+ void (*pm)(struct uart_port *port,
+ unsigned int state, unsigned int old);
+};
+
+struct irq_info {
+ spinlock_t lock;
+ struct list_head *head;
+};
+
+static struct irq_info irq_lists[NR_IRQS];
+
+/*
+ * 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,
+ .flags = UART_CAP_FIFO,
+ },
+ [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,
+ },
+};
+
+static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
+{
+ offset <<= up->port.regshift;
+
+ switch (up->port.iotype) {
+ case UPIO_HUB6:
+ outb(up->port.hub6 - 1 + offset, up->port.iobase);
+ return inb(up->port.iobase + 1);
+
+ case UPIO_MEM:
+ return readb(up->port.membase + offset);
+
+ case UPIO_MEM32:
+ return readl(up->port.membase + offset);
+
+ default:
+ return inb(up->port.iobase + offset);
+ }
+}
+
+static _INLINE_ void
+serial_out(struct uart_8250_port *up, int offset, int value)
+{
+ offset <<= up->port.regshift;
+
+ switch (up->port.iotype) {
+ case UPIO_HUB6:
+ outb(up->port.hub6 - 1 + offset, up->port.iobase);
+ outb(value, up->port.iobase + 1);
+ break;
+
+ case UPIO_MEM:
+ writeb(value, up->port.membase + offset);
+ break;
+
+ case UPIO_MEM32:
+ writel(value, up->port.membase + offset);
+ break;
+
+ default:
+ outb(value, up->port.iobase + offset);
+ }
+}
+
+/*
+ * We used to support using pause I/O for certain machines. We
+ * haven't supported this for a while, but just in case it's badly
+ * needed for certain old 386 machines, I've left these #define's
+ * in....
+ */
+#define serial_inp(up, offset) serial_in(up, offset)
+#define serial_outp(up, offset, value) serial_out(up, 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 inline void serial8250_clear_fifos(struct uart_8250_port *p)
+{
+ if (p->capabilities & UART_CAP_FIFO) {
+ serial_outp(p, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_outp(p, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+ serial_outp(p, UART_FCR, 0);
+ }
+}
+
+/*
+ * 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 inline void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
+{
+ if (p->capabilities & UART_CAP_SLEEP) {
+ if (p->capabilities & UART_CAP_EFR) {
+ serial_outp(p, UART_LCR, 0xBF);
+ serial_outp(p, UART_EFR, UART_EFR_ECB);
+ serial_outp(p, UART_LCR, 0);
+ }
+ serial_outp(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+ if (p->capabilities & UART_CAP_EFR) {
+ serial_outp(p, UART_LCR, 0xBF);
+ serial_outp(p, UART_EFR, 0);
+ serial_outp(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_inp(up, UART_RSA_MSR);
+ result = mode & UART_RSA_MSR_FIFO;
+
+ if (!result) {
+ serial_outp(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
+ mode = serial_inp(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_outp(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_inp(up, UART_RSA_MSR);
+ result = !(mode & UART_RSA_MSR_FIFO);
+
+ if (!result) {
+ serial_outp(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
+ mode = serial_inp(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_dll, old_dlm, old_lcr;
+ int count;
+
+ old_lcr = serial_inp(up, UART_LCR);
+ serial_outp(up, UART_LCR, 0);
+ old_fcr = serial_inp(up, UART_FCR);
+ old_mcr = serial_inp(up, UART_MCR);
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+ serial_outp(up, UART_MCR, UART_MCR_LOOP);
+ serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ old_dll = serial_inp(up, UART_DLL);
+ old_dlm = serial_inp(up, UART_DLM);
+ serial_outp(up, UART_DLL, 0x01);
+ serial_outp(up, UART_DLM, 0x00);
+ serial_outp(up, UART_LCR, 0x03);
+ for (count = 0; count < 256; count++)
+ serial_outp(up, UART_TX, count);
+ mdelay(20);/* FIXME - schedule_timeout */
+ for (count = 0; (serial_inp(up, UART_LSR) & UART_LSR_DR) &&
+ (count < 256); count++)
+ serial_inp(up, UART_RX);
+ serial_outp(up, UART_FCR, old_fcr);
+ serial_outp(up, UART_MCR, old_mcr);
+ serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_DLL, old_dll);
+ serial_outp(up, UART_DLM, old_dlm);
+ serial_outp(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_inp(p, UART_LCR);
+ serial_outp(p, UART_LCR, UART_LCR_DLAB);
+
+ old_dll = serial_inp(p, UART_DLL);
+ old_dlm = serial_inp(p, UART_DLM);
+
+ serial_outp(p, UART_DLL, 0);
+ serial_outp(p, UART_DLM, 0);
+
+ id = serial_inp(p, UART_DLL) | serial_inp(p, UART_DLM) << 8;
+
+ serial_outp(p, UART_DLL, old_dll);
+ serial_outp(p, UART_DLM, old_dlm);
+ serial_outp(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, 0xBF);
+ 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;
+ up->rev = rev | (id3 << 8);
+ 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) {
+ if (id2 == 0x10)
+ up->rev = id1 & 255;
+ 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_outp(up, UART_SCR, 0xa5);
+ status1 = serial_in(up, UART_SCR);
+ serial_outp(up, UART_SCR, 0x5a);
+ status2 = serial_in(up, UART_SCR);
+ serial_outp(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://www.exar.com/info.php?pdf=dan180_oct2004.pdf
+ */
+ if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * 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;
+
+ /*
+ * Check for presence of the EFR when DLAB is set.
+ * Only ST16C650V1 UARTs pass this test.
+ */
+ serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ if (serial_in(up, UART_EFR) == 0) {
+ serial_outp(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_outp(up, UART_EFR, 0);
+ return;
+ }
+
+ /*
+ * Maybe it requires 0xbf to be written to the LCR.
+ * (other ST16C650V2 UARTs, TI16C752A, etc)
+ */
+ serial_outp(up, UART_LCR, 0xBF);
+ 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
+ * On PowerPC we don't want to change baud_base, as we have
+ * a number of different divisors. -- Tom Rini
+ */
+ serial_outp(up, UART_LCR, 0);
+ status1 = serial_in(up, UART_MCR);
+ serial_outp(up, UART_LCR, 0xE0);
+ status2 = serial_in(up, 0x02); /* EXCR1 */
+
+ if (!((status2 ^ status1) & UART_MCR_LOOP)) {
+ serial_outp(up, UART_LCR, 0);
+ serial_outp(up, UART_MCR, status1 ^ UART_MCR_LOOP);
+ serial_outp(up, UART_LCR, 0xE0);
+ status2 = serial_in(up, 0x02); /* EXCR1 */
+ serial_outp(up, UART_LCR, 0);
+ serial_outp(up, UART_MCR, status1);
+
+ if ((status2 ^ status1) & UART_MCR_LOOP) {
+#ifndef CONFIG_PPC
+ serial_outp(up, UART_LCR, 0xE0);
+ status1 = serial_in(up, 0x04); /* EXCR1 */
+ status1 &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
+ status1 |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
+ serial_outp(up, 0x04, status1);
+ serial_outp(up, UART_LCR, 0);
+ up->port.uartclk = 921600*16;
+#endif
+
+ 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_outp(up, UART_LCR, 0);
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+ status1 = serial_in(up, UART_IIR) >> 5;
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+ status2 = serial_in(up, UART_IIR) >> 5;
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_outp(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_outp(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_outp(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;
+ 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_outp(up, UART_IER, iersave);
+}
+
+/*
+ * 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;
+ unsigned long flags;
+
+ if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
+ return;
+
+ DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%p): ",
+ up->port.line, up->port.iobase, up->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(&up->port.lock, flags);
+// save_flags(flags); cli();
+
+ up->capabilities = 0;
+
+ if (!(up->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_inp(up, UART_IER);
+ serial_outp(up, UART_IER, 0);
+#ifdef __i386__
+ outb(0xff, 0x080);
+#endif
+ scratch2 = serial_inp(up, UART_IER);
+ serial_outp(up, UART_IER, 0x0F);
+#ifdef __i386__
+ outb(0, 0x080);
+#endif
+ scratch3 = serial_inp(up, UART_IER);
+ serial_outp(up, UART_IER, scratch);
+ if (scratch2 != 0 || scratch3 != 0x0F) {
+ /*
+ * We failed; there's nothing here
+ */
+ 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 (!(up->port.flags & UPF_SKIP_TEST)) {
+ serial_outp(up, UART_MCR, UART_MCR_LOOP | 0x0A);
+ status1 = serial_inp(up, UART_MSR) & 0xF0;
+ serial_outp(up, UART_MCR, save_mcr);
+ if (status1 != 0x90) {
+ 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 its 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_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_EFR, 0);
+ serial_outp(up, UART_LCR, 0);
+
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ scratch = serial_in(up, UART_IIR) >> 6;
+
+ DEBUG_AUTOCONF("iir=%d ", scratch);
+
+ switch (scratch) {
+ case 0:
+ autoconfig_8250(up);
+ break;
+ case 1:
+ up->port.type = PORT_UNKNOWN;
+ break;
+ case 2:
+ up->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 (up->port.type == PORT_16550A && probeflags & PROBE_RSA) {
+ int i;
+
+ for (i = 0 ; i < probe_rsa_count; ++i) {
+ if (probe_rsa[i] == up->port.iobase &&
+ __enable_rsa(up)) {
+ up->port.type = PORT_RSA;
+ break;
+ }
+ }
+ }
+#endif
+ serial_outp(up, UART_LCR, save_lcr);
+
+ if (up->capabilities != uart_config[up->port.type].flags) {
+ printk(KERN_WARNING
+ "ttyS%d: detected caps %08x should be %08x\n",
+ up->port.line, up->capabilities,
+ uart_config[up->port.type].flags);
+ }
+
+ up->port.fifosize = uart_config[up->port.type].fifo_size;
+ up->capabilities = uart_config[up->port.type].flags;
+ up->tx_loadsz = uart_config[up->port.type].tx_loadsz;
+
+ if (up->port.type == PORT_UNKNOWN)
+ goto out;
+
+ /*
+ * Reset the UART.
+ */
+#ifdef CONFIG_SERIAL_8250_RSA
+ if (up->port.type == PORT_RSA)
+ serial_outp(up, UART_RSA_FRR, 0);
+#endif
+ serial_outp(up, UART_MCR, save_mcr);
+ serial8250_clear_fifos(up);
+ (void)serial_in(up, UART_RX);
+ serial_outp(up, UART_IER, 0);
+
+ out:
+ spin_unlock_irqrestore(&up->port.lock, flags);
+// restore_flags(flags);
+ DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
+}
+
+static void autoconfig_irq(struct uart_8250_port *up)
+{
+ unsigned char save_mcr, save_ier;
+ unsigned char save_ICP = 0;
+ unsigned int ICP = 0;
+ unsigned long irqs;
+ int irq;
+
+ if (up->port.flags & UPF_FOURPORT) {
+ ICP = (up->port.iobase & 0xfe0) | 0x1f;
+ save_ICP = inb_p(ICP);
+ outb_p(0x80, ICP);
+ (void) inb_p(ICP);
+ }
+
+ /* forget possible initially masked and pending IRQ */
+ probe_irq_off(probe_irq_on());
+ save_mcr = serial_inp(up, UART_MCR);
+ save_ier = serial_inp(up, UART_IER);
+ serial_outp(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
+
+ irqs = probe_irq_on();
+ serial_outp(up, UART_MCR, 0);
+ udelay (10);
+ if (up->port.flags & UPF_FOURPORT) {
+ serial_outp(up, UART_MCR,
+ UART_MCR_DTR | UART_MCR_RTS);
+ } else {
+ serial_outp(up, UART_MCR,
+ UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
+ }
+ serial_outp(up, UART_IER, 0x0f); /* enable all intrs */
+ (void)serial_inp(up, UART_LSR);
+ (void)serial_inp(up, UART_RX);
+ (void)serial_inp(up, UART_IIR);
+ (void)serial_inp(up, UART_MSR);
+ serial_outp(up, UART_TX, 0xFF);
+ udelay (20);
+ irq = probe_irq_off(irqs);
+
+ serial_outp(up, UART_MCR, save_mcr);
+ serial_outp(up, UART_IER, save_ier);
+
+ if (up->port.flags & UPF_FOURPORT)
+ outb_p(save_ICP, ICP);
+
+ up->port.irq = (irq > 0) ? irq : 0;
+}
+
+static void serial8250_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ if (up->ier & UART_IER_THRI) {
+ up->ier &= ~UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+
+ /*
+ * We only do this from uart_stop - if we run out of
+ * characters to send, we don't want to prevent the
+ * FIFO from emptying.
+ */
+ if (up->port.type == PORT_16C950 && tty_stop) {
+ up->acr |= UART_ACR_TXDIS;
+ serial_icr_write(up, UART_ACR, up->acr);
+ }
+}
+
+static void serial8250_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ if (!(up->ier & UART_IER_THRI)) {
+ up->ier |= UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+ /*
+ * We only do this from uart_start
+ */
+ if (tty_start && up->port.type == PORT_16C950) {
+ 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 = (struct uart_8250_port *)port;
+
+ up->ier &= ~UART_IER_RLSI;
+ up->port.read_status_mask &= ~UART_LSR_DR;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static void serial8250_enable_ms(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ up->ier |= UART_IER_MSI;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static _INLINE_ void
+receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs)
+{
+ struct tty_struct *tty = up->port.info->tty;
+ unsigned char ch, lsr = *status;
+ int max_count = 256;
+ char flag;
+
+ do {
+ /* The following is not allowed by the tty layer and
+ unsafe. It should be fixed ASAP */
+ if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
+ if (tty->low_latency) {
+ spin_unlock(&up->port.lock);
+ tty_flip_buffer_push(tty);
+ spin_lock(&up->port.lock);
+ }
+ /* If this failed then we will throw away the
+ bytes but must do so to clear interrupts */
+ }
+ ch = serial_inp(up, UART_RX);
+ flag = TTY_NORMAL;
+ up->port.icount.rx++;
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+ /*
+ * Recover the break flag from console xmit
+ */
+ if (up->port.line == up->port.cons->index) {
+ lsr |= up->lsr_break_flag;
+ up->lsr_break_flag = 0;
+ }
+#endif
+
+ if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE |
+ UART_LSR_FE | UART_LSR_OE))) {
+ /*
+ * For statistics only
+ */
+ if (lsr & UART_LSR_BI) {
+ lsr &= ~(UART_LSR_FE | UART_LSR_PE);
+ up->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(&up->port))
+ goto ignore_char;
+ } else if (lsr & UART_LSR_PE)
+ up->port.icount.parity++;
+ else if (lsr & UART_LSR_FE)
+ up->port.icount.frame++;
+ if (lsr & UART_LSR_OE)
+ up->port.icount.overrun++;
+
+ /*
+ * Mask off conditions which should be ingored.
+ */
+ lsr &= up->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(&up->port, ch, regs))
+ goto ignore_char;
+ if ((lsr & up->port.ignore_status_mask) == 0) {
+ tty_insert_flip_char(tty, ch, flag);
+ }
+ if ((lsr & UART_LSR_OE) &&
+ tty->flip.count < TTY_FLIPBUF_SIZE) {
+ /*
+ * Overrun is special, since it's reported
+ * immediately, and doesn't affect the current
+ * character.
+ */
+ tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ }
+ ignore_char:
+ lsr = serial_inp(up, UART_LSR);
+ } while ((lsr & UART_LSR_DR) && (max_count-- > 0));
+ spin_unlock(&up->port.lock);
+ tty_flip_buffer_push(tty);
+ spin_lock(&up->port.lock);
+ *status = lsr;
+}
+
+static _INLINE_ void transmit_chars(struct uart_8250_port *up)
+{
+ struct circ_buf *xmit = &up->port.info->xmit;
+ int count;
+
+ if (up->port.x_char) {
+ serial_outp(up, UART_TX, up->port.x_char);
+ up->port.icount.tx++;
+ up->port.x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+ serial8250_stop_tx(&up->port, 0);
+ return;
+ }
+
+ count = up->tx_loadsz;
+ do {
+ serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ up->port.icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&up->port);
+
+ DEBUG_INTR("THRE...");
+
+ if (uart_circ_empty(xmit))
+ serial8250_stop_tx(&up->port, 0);
+}
+
+static _INLINE_ void check_modem_status(struct uart_8250_port *up)
+{
+ int status;
+
+ status = serial_in(up, UART_MSR);
+
+ if ((status & UART_MSR_ANY_DELTA) == 0)
+ return;
+
+ if (status & UART_MSR_TERI)
+ up->port.icount.rng++;
+ if (status & UART_MSR_DDSR)
+ up->port.icount.dsr++;
+ if (status & UART_MSR_DDCD)
+ uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
+ if (status & UART_MSR_DCTS)
+ uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
+
+ wake_up_interruptible(&up->port.info->delta_msr_wait);
+}
+
+/*
+ * This handles the interrupt from one port.
+ */
+static inline void
+serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
+{
+ unsigned int status = serial_inp(up, UART_LSR);
+
+ DEBUG_INTR("status = %x...", status);
+
+ if (status & UART_LSR_DR)
+ receive_chars(up, &status, regs);
+ check_modem_status(up);
+ if (status & UART_LSR_THRE)
+ transmit_chars(up);
+}
+
+/*
+ * 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 pt_regs *regs)
+{
+ 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;
+ unsigned int iir;
+
+ up = list_entry(l, struct uart_8250_port, list);
+
+ iir = serial_in(up, UART_IIR);
+ if (!(iir & UART_IIR_NO_INT)) {
+ spin_lock(&up->port.lock);
+ serial8250_handle_port(up, regs);
+ spin_unlock(&up->port.lock);
+
+ handled = 1;
+
+ 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(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);
+}
+
+static int serial_link_irq_chain(struct uart_8250_port *up)
+{
+ struct irq_info *i = irq_lists + up->port.irq;
+ int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
+
+ 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);
+
+ 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 = irq_lists + up->port.irq;
+
+ BUG_ON(i->head == NULL);
+
+ if (list_empty(i->head))
+ free_irq(up->port.irq, i);
+
+ serial_do_unlink(i, up);
+}
+
+/*
+ * 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;
+ unsigned int timeout;
+ unsigned int iir;
+
+ iir = serial_in(up, UART_IIR);
+ if (!(iir & UART_IIR_NO_INT)) {
+ spin_lock(&up->port.lock);
+ serial8250_handle_port(up, NULL);
+ spin_unlock(&up->port.lock);
+ }
+
+ timeout = up->port.timeout;
+ timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
+ mod_timer(&up->timer, jiffies + timeout);
+}
+
+static unsigned int serial8250_tx_empty(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ unsigned int ret;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ return ret;
+}
+
+static unsigned int serial8250_get_mctrl(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ unsigned char status;
+ unsigned int ret;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ status = serial_in(up, UART_MSR);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ 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 = (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_out(up, UART_MCR, mcr);
+}
+
+static void serial8250_break_ctl(struct uart_port *port, int break_state)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (break_state == -1)
+ up->lcr |= UART_LCR_SBC;
+ else
+ up->lcr &= ~UART_LCR_SBC;
+ serial_out(up, UART_LCR, up->lcr);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static int serial8250_startup(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ int retval;
+
+ up->capabilities = uart_config[up->port.type].flags;
+ up->mcr = 0;
+
+ if (up->port.type == PORT_16C950) {
+ /* Wake up and initialize UART */
+ up->acr = 0;
+ serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_EFR, UART_EFR_ECB);
+ serial_outp(up, UART_IER, 0);
+ serial_outp(up, UART_LCR, 0);
+ serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
+ serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_EFR, UART_EFR_ECB);
+ serial_outp(up, 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 reeanbled in set_termios())
+ */
+ serial8250_clear_fifos(up);
+
+ /*
+ * Clear the interrupt registers.
+ */
+ (void) serial_inp(up, UART_LSR);
+ (void) serial_inp(up, UART_RX);
+ (void) serial_inp(up, UART_IIR);
+ (void) serial_inp(up, 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 (!(up->port.flags & UPF_BUGGY_UART) &&
+ (serial_inp(up, UART_LSR) == 0xff)) {
+ printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
+ return -ENODEV;
+ }
+
+ /*
+ * For a XR16C850, we need to set the trigger levels
+ */
+ if (up->port.type == PORT_16850) {
+ unsigned char fctr;
+
+ serial_outp(up, UART_LCR, 0xbf);
+
+ fctr = serial_inp(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
+ serial_outp(up, UART_FCTR, fctr | UART_FCTR_TRGD | UART_FCTR_RX);
+ serial_outp(up, UART_TRG, UART_TRG_96);
+ serial_outp(up, UART_FCTR, fctr | UART_FCTR_TRGD | UART_FCTR_TX);
+ serial_outp(up, UART_TRG, UART_TRG_96);
+
+ serial_outp(up, UART_LCR, 0);
+ }
+
+ /*
+ * 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 (!is_real_interrupt(up->port.irq)) {
+ unsigned int timeout = up->port.timeout;
+
+ timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
+
+ up->timer.data = (unsigned long)up;
+ mod_timer(&up->timer, jiffies + timeout);
+ } else {
+ retval = serial_link_irq_chain(up);
+ if (retval)
+ return retval;
+ }
+
+ /*
+ * Now, initialize the UART
+ */
+ serial_outp(up, UART_LCR, UART_LCR_WLEN8);
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (up->port.flags & UPF_FOURPORT) {
+ if (!is_real_interrupt(up->port.irq))
+ up->port.mctrl |= TIOCM_OUT1;
+ } else
+ /*
+ * Most PC uarts need OUT2 raised to enable interrupts.
+ */
+ if (is_real_interrupt(up->port.irq))
+ up->port.mctrl |= TIOCM_OUT2;
+
+ serial8250_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ /*
+ * 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_outp(up, UART_IER, up->ier);
+
+ if (up->port.flags & UPF_FOURPORT) {
+ unsigned int icp;
+ /*
+ * Enable interrupts on the AST Fourport board
+ */
+ icp = (up->port.iobase & 0xfe0) | 0x01f;
+ outb_p(0x80, icp);
+ (void) inb_p(icp);
+ }
+
+ /*
+ * And clear the interrupt registers again for luck.
+ */
+ (void) serial_inp(up, UART_LSR);
+ (void) serial_inp(up, UART_RX);
+ (void) serial_inp(up, UART_IIR);
+ (void) serial_inp(up, UART_MSR);
+
+ return 0;
+}
+
+static void serial8250_shutdown(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+
+ /*
+ * Disable interrupts from this port
+ */
+ up->ier = 0;
+ serial_outp(up, UART_IER, 0);
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (up->port.flags & UPF_FOURPORT) {
+ /* reset interrupts on the AST Fourport board */
+ inb((up->port.iobase & 0xfe0) | 0x1f);
+ up->port.mctrl |= TIOCM_OUT1;
+ } else
+ up->port.mctrl &= ~TIOCM_OUT2;
+
+ serial8250_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ /*
+ * Disable break condition and FIFOs
+ */
+ serial_out(up, UART_LCR, serial_inp(up, 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.
+ */
+ (void) serial_in(up, UART_RX);
+
+ if (!is_real_interrupt(up->port.irq))
+ del_timer_sync(&up->timer);
+ else
+ 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;
+}
+
+static void
+serial8250_set_termios(struct uart_port *port, struct termios *termios,
+ struct termios *old)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned char cval, fcr = 0;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ cval = 0x00;
+ break;
+ case CS6:
+ cval = 0x01;
+ break;
+ case CS7:
+ cval = 0x02;
+ break;
+ default:
+ case CS8:
+ cval = 0x03;
+ break;
+ }
+
+ if (termios->c_cflag & CSTOPB)
+ cval |= 0x04;
+ if (termios->c_cflag & PARENB)
+ cval |= UART_LCR_PARITY;
+ 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, 0, port->uartclk/16);
+ quot = serial8250_get_divisor(port, baud);
+
+ /*
+ * Work around a bug in the Oxford Semiconductor 952 rev B
+ * chip which causes it to seriously miscalculate baud rates
+ * when DLL is 0.
+ */
+ if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
+ up->rev == 0x5201)
+ quot ++;
+
+ if (up->capabilities & UART_CAP_FIFO && up->port.fifosize > 1) {
+ if (baud < 2400)
+ fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
+ else
+ fcr = uart_config[up->port.type].fcr;
+ }
+
+ /*
+ * 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 && up->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(&up->port.lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+ if (termios->c_iflag & INPCK)
+ up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ up->port.read_status_mask |= UART_LSR_BI;
+
+ /*
+ * Characteres to ignore
+ */
+ up->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+ if (termios->c_iflag & IGNBRK) {
+ up->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)
+ up->port.ignore_status_mask |= UART_LSR_OE;
+ }
+
+ /*
+ * ignore all characters if CREAD is not set
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ up->port.ignore_status_mask |= UART_LSR_DR;
+
+ /*
+ * CTS flow control flag and modem status interrupts
+ */
+ up->ier &= ~UART_IER_MSI;
+ if (UART_ENABLE_MS(&up->port, termios->c_cflag))
+ up->ier |= UART_IER_MSI;
+ if (up->capabilities & UART_CAP_UUE)
+ up->ier |= UART_IER_UUE | UART_IER_RTOIE;
+
+ serial_out(up, 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_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_EFR, efr);
+ }
+
+ if (up->capabilities & UART_NATSEMI) {
+ /* Switch to bank 2 not bank 1, to avoid resetting EXCR2 */
+ serial_outp(up, UART_LCR, 0xe0);
+ } else {
+ serial_outp(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
+ }
+
+ serial_outp(up, UART_DLL, quot & 0xff); /* LS of divisor */
+ serial_outp(up, UART_DLM, quot >> 8); /* MS of divisor */
+
+ /*
+ * 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 (up->port.type == PORT_16750)
+ serial_outp(up, UART_FCR, fcr);
+
+ serial_outp(up, UART_LCR, cval); /* reset DLAB */
+ up->lcr = cval; /* Save LCR */
+ if (up->port.type != PORT_16750) {
+ if (fcr & UART_FCR_ENABLE_FIFO) {
+ /* emulated UARTs (Lucent Venus 167x) need two steps */
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ }
+ serial_outp(up, UART_FCR, fcr); /* set fcr */
+ }
+ serial8250_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static void
+serial8250_pm(struct uart_port *port, unsigned int state,
+ unsigned int oldstate)
+{
+ struct uart_8250_port *p = (struct uart_8250_port *)port;
+
+ serial8250_set_sleep(p, state != 0);
+
+ if (p->pm)
+ p->pm(port, state, oldstate);
+}
+
+/*
+ * Resource handling.
+ */
+static int serial8250_request_std_resource(struct uart_8250_port *up)
+{
+ unsigned int size = 8 << up->port.regshift;
+ int ret = 0;
+
+ switch (up->port.iotype) {
+ case UPIO_MEM:
+ if (!up->port.mapbase)
+ break;
+
+ if (!request_mem_region(up->port.mapbase, size, "serial")) {
+ ret = -EBUSY;
+ break;
+ }
+
+ if (up->port.flags & UPF_IOREMAP) {
+ up->port.membase = ioremap(up->port.mapbase, size);
+ if (!up->port.membase) {
+ release_mem_region(up->port.mapbase, size);
+ ret = -ENOMEM;
+ }
+ }
+ break;
+
+ case UPIO_HUB6:
+ case UPIO_PORT:
+ if (!request_region(up->port.iobase, size, "serial"))
+ ret = -EBUSY;
+ break;
+ }
+ return ret;
+}
+
+static void serial8250_release_std_resource(struct uart_8250_port *up)
+{
+ unsigned int size = 8 << up->port.regshift;
+
+ switch (up->port.iotype) {
+ case UPIO_MEM:
+ if (!up->port.mapbase)
+ break;
+
+ if (up->port.flags & UPF_IOREMAP) {
+ iounmap(up->port.membase);
+ up->port.membase = NULL;
+ }
+
+ release_mem_region(up->port.mapbase, size);
+ break;
+
+ case UPIO_HUB6:
+ case UPIO_PORT:
+ release_region(up->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;
+ int ret = 0;
+
+ switch (up->port.iotype) {
+ case UPIO_MEM:
+ ret = -EINVAL;
+ break;
+
+ case UPIO_HUB6:
+ case UPIO_PORT:
+ start += up->port.iobase;
+ if (!request_region(start, size, "serial-rsa"))
+ 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;
+
+ switch (up->port.iotype) {
+ case UPIO_MEM:
+ break;
+
+ case UPIO_HUB6:
+ case UPIO_PORT:
+ release_region(up->port.iobase + offset, size);
+ break;
+ }
+}
+
+static void serial8250_release_port(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ serial8250_release_std_resource(up);
+ if (up->port.type == PORT_RSA)
+ serial8250_release_rsa_resource(up);
+}
+
+static int serial8250_request_port(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ int ret = 0;
+
+ ret = serial8250_request_std_resource(up);
+ if (ret == 0 && up->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 = (struct uart_8250_port *)port;
+ int probeflags = PROBE_ANY;
+ int ret;
+
+ /*
+ * Don't probe for MCA ports on non-MCA machines.
+ */
+ if (up->port.flags & UPF_BOOT_ONLYMCA && !MCA_bus)
+ return;
+
+ /*
+ * Find the region that we can probe for. This in turn
+ * tells us whether we can probe for the type of port.
+ */
+ ret = serial8250_request_std_resource(up);
+ if (ret < 0)
+ return;
+
+ ret = serial8250_request_rsa_resource(up);
+ if (ret < 0)
+ probeflags &= ~PROBE_RSA;
+
+ if (flags & UART_CONFIG_TYPE)
+ autoconfig(up, probeflags);
+ if (up->port.type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
+ autoconfig_irq(up);
+
+ if (up->port.type != PORT_RSA && probeflags & PROBE_RSA)
+ serial8250_release_rsa_resource(up);
+ if (up->port.type == PORT_UNKNOWN)
+ serial8250_release_std_resource(up);
+}
+
+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,
+ .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,
+};
+
+static struct uart_8250_port serial8250_ports[UART_NR];
+
+static void __init serial8250_isa_init_ports(void)
+{
+ struct uart_8250_port *up;
+ static int first = 1;
+ int i;
+
+ if (!first)
+ return;
+ first = 0;
+
+ for (i = 0; i < UART_NR; i++) {
+ struct uart_8250_port *up = &serial8250_ports[i];
+
+ up->port.line = i;
+ spin_lock_init(&up->port.lock);
+
+ init_timer(&up->timer);
+ up->timer.function = serial8250_timeout;
+
+ /*
+ * ALPHA_KLUDGE_MCR needs to be killed.
+ */
+ up->mcr_mask = ~ALPHA_KLUDGE_MCR;
+ up->mcr_force = ALPHA_KLUDGE_MCR;
+
+ up->port.ops = &serial8250_pops;
+ }
+
+ for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port);
+ i++, up++) {
+ up->port.iobase = old_serial_port[i].port;
+ up->port.irq = irq_canonicalize(old_serial_port[i].irq);
+ up->port.uartclk = old_serial_port[i].baud_base * 16;
+ up->port.flags = old_serial_port[i].flags;
+ up->port.hub6 = old_serial_port[i].hub6;
+ up->port.membase = old_serial_port[i].iomem_base;
+ up->port.iotype = old_serial_port[i].io_type;
+ up->port.regshift = old_serial_port[i].iomem_reg_shift;
+ if (share_irqs)
+ up->port.flags |= UPF_SHARE_IRQ;
+ }
+}
+
+static void __init
+serial8250_register_ports(struct uart_driver *drv, struct device *dev)
+{
+ int i;
+
+ serial8250_isa_init_ports();
+
+ for (i = 0; i < UART_NR; i++) {
+ struct uart_8250_port *up = &serial8250_ports[i];
+
+ up->port.dev = dev;
+ uart_add_one_port(drv, &up->port);
+ }
+}
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+
+#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
+
+/*
+ * Wait for transmitter & holding register to empty
+ */
+static inline void wait_for_xmitr(struct uart_8250_port *up)
+{
+ unsigned int status, tmout = 10000;
+
+ /* Wait up to 10ms for the character(s) to be sent. */
+ do {
+ status = serial_in(up, UART_LSR);
+
+ if (status & UART_LSR_BI)
+ up->lsr_break_flag = UART_LSR_BI;
+
+ if (--tmout == 0)
+ break;
+ udelay(1);
+ } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
+
+ /* Wait up to 1s for flow control if necessary */
+ if (up->port.flags & UPF_CONS_FLOW) {
+ tmout = 1000000;
+ while (--tmout &&
+ ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
+ udelay(1);
+ }
+}
+
+/*
+ * 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];
+ unsigned int ier;
+ int i;
+
+ /*
+ * First save the UER then disable the interrupts
+ */
+ ier = serial_in(up, UART_IER);
+
+ if (up->capabilities & UART_CAP_UUE)
+ serial_out(up, UART_IER, UART_IER_UUE);
+ else
+ serial_out(up, UART_IER, 0);
+
+ /*
+ * Now, do each character
+ */
+ for (i = 0; i < count; i++, s++) {
+ wait_for_xmitr(up);
+
+ /*
+ * Send the character out.
+ * If a LF, also do CR...
+ */
+ serial_out(up, UART_TX, *s);
+ if (*s == 10) {
+ wait_for_xmitr(up);
+ serial_out(up, UART_TX, 13);
+ }
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ wait_for_xmitr(up);
+ serial_out(up, UART_IER, ier);
+}
+
+static int 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.
+ */
+ 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 struct uart_driver serial8250_reg;
+static struct console serial8250_console = {
+ .name = "ttyS",
+ .write = serial8250_console_write,
+ .device = uart_console_device,
+ .setup = serial8250_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .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);
+
+static int __init find_port(struct uart_port *p)
+{
+ int line;
+ struct uart_port *port;
+
+ for (line = 0; line < UART_NR; line++) {
+ port = &serial8250_ports[line].port;
+ if (p->iotype == port->iotype &&
+ p->iobase == port->iobase &&
+ p->membase == port->membase)
+ return line;
+ }
+ return -ENODEV;
+}
+
+int __init serial8250_start_console(struct uart_port *port, char *options)
+{
+ int line;
+
+ line = find_port(port);
+ if (line < 0)
+ return -ENODEV;
+
+ add_preferred_console("ttyS", line, options);
+ printk("Adding console on ttyS%d at %s 0x%lx (options '%s')\n",
+ line, port->iotype == UPIO_MEM ? "MMIO" : "I/O port",
+ port->iotype == UPIO_MEM ? (unsigned long) port->mapbase :
+ (unsigned long) port->iobase, options);
+ if (!(serial8250_console.flags & CON_ENABLED)) {
+ serial8250_console.flags &= ~CON_PRINTBUFFER;
+ register_console(&serial8250_console);
+ }
+ return line;
+}
+
+#define SERIAL8250_CONSOLE &serial8250_console
+#else
+#define SERIAL8250_CONSOLE NULL
+#endif
+
+static struct uart_driver serial8250_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial",
+ .devfs_name = "tts/",
+ .dev_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .nr = UART_NR,
+ .cons = SERIAL8250_CONSOLE,
+};
+
+int __init early_serial_setup(struct uart_port *port)
+{
+ if (port->line >= ARRAY_SIZE(serial8250_ports))
+ return -ENODEV;
+
+ serial8250_isa_init_ports();
+ serial8250_ports[port->line].port = *port;
+ serial8250_ports[port->line].port.ops = &serial8250_pops;
+ return 0;
+}
+
+/**
+ * serial8250_suspend_port - suspend one serial port
+ * @line: serial line number
+ * @level: the level of port suspension, as per uart_suspend_port
+ *
+ * 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
+ * @level: the level of port resumption, as per uart_resume_port
+ *
+ * Resume one serial port.
+ */
+void serial8250_resume_port(int line)
+{
+ uart_resume_port(&serial8250_reg, &serial8250_ports[line].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 __devinit serial8250_probe(struct device *dev)
+{
+ struct plat_serial8250_port *p = dev->platform_data;
+ struct uart_port port;
+
+ memset(&port, 0, sizeof(struct uart_port));
+
+ for (; p && p->flags != 0; p++) {
+ port.iobase = p->iobase;
+ port.membase = p->membase;
+ port.irq = p->irq;
+ port.uartclk = p->uartclk;
+ port.regshift = p->regshift;
+ port.iotype = p->iotype;
+ port.flags = p->flags;
+ port.mapbase = p->mapbase;
+ port.dev = dev;
+ if (share_irqs)
+ port.flags |= UPF_SHARE_IRQ;
+ serial8250_register_port(&port);
+ }
+ return 0;
+}
+
+/*
+ * Remove serial ports registered against a platform device.
+ */
+static int __devexit serial8250_remove(struct device *dev)
+{
+ int i;
+
+ for (i = 0; i < UART_NR; i++) {
+ struct uart_8250_port *up = &serial8250_ports[i];
+
+ if (up->port.dev == dev)
+ serial8250_unregister_port(i);
+ }
+ return 0;
+}
+
+static int serial8250_suspend(struct device *dev, pm_message_t state, u32 level)
+{
+ int i;
+
+ if (level != SUSPEND_DISABLE)
+ return 0;
+
+ 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)
+ uart_suspend_port(&serial8250_reg, &up->port);
+ }
+
+ return 0;
+}
+
+static int serial8250_resume(struct device *dev, u32 level)
+{
+ int i;
+
+ if (level != RESUME_ENABLE)
+ return 0;
+
+ 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)
+ uart_resume_port(&serial8250_reg, &up->port);
+ }
+
+ return 0;
+}
+
+static struct device_driver serial8250_isa_driver = {
+ .name = "serial8250",
+ .bus = &platform_bus_type,
+ .probe = serial8250_probe,
+ .remove = __devexit_p(serial8250_remove),
+ .suspend = serial8250_suspend,
+ .resume = serial8250_resume,
+};
+
+/*
+ * 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_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 DECLARE_MUTEX(serial_sem);
+
+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 < 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 < 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_port - register a serial port
+ * @port: 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_port(struct uart_port *port)
+{
+ struct uart_8250_port *uart;
+ int ret = -ENOSPC;
+
+ if (port->uartclk == 0)
+ return -EINVAL;
+
+ down(&serial_sem);
+
+ uart = serial8250_find_match_or_unused(port);
+ if (uart) {
+ uart_remove_one_port(&serial8250_reg, &uart->port);
+
+ uart->port.iobase = port->iobase;
+ uart->port.membase = port->membase;
+ uart->port.irq = port->irq;
+ uart->port.uartclk = port->uartclk;
+ uart->port.fifosize = port->fifosize;
+ uart->port.regshift = port->regshift;
+ uart->port.iotype = port->iotype;
+ uart->port.flags = port->flags | UPF_BOOT_AUTOCONF;
+ uart->port.mapbase = port->mapbase;
+ if (port->dev)
+ uart->port.dev = port->dev;
+
+ ret = uart_add_one_port(&serial8250_reg, &uart->port);
+ if (ret == 0)
+ ret = uart->port.line;
+ }
+ up(&serial_sem);
+
+ return ret;
+}
+EXPORT_SYMBOL(serial8250_register_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];
+
+ down(&serial_sem);
+ 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_add_one_port(&serial8250_reg, &uart->port);
+ } else {
+ uart->port.dev = NULL;
+ }
+ up(&serial_sem);
+}
+EXPORT_SYMBOL(serial8250_unregister_port);
+
+static int __init serial8250_init(void)
+{
+ int ret, i;
+
+ printk(KERN_INFO "Serial: 8250/16550 driver $Revision: 1.90 $ "
+ "%d ports, IRQ sharing %sabled\n", (int) UART_NR,
+ share_irqs ? "en" : "dis");
+
+ for (i = 0; i < NR_IRQS; i++)
+ spin_lock_init(&irq_lists[i].lock);
+
+ ret = uart_register_driver(&serial8250_reg);
+ if (ret)
+ goto out;
+
+ serial8250_isa_devs = platform_device_register_simple("serial8250",
+ -1, NULL, 0);
+ if (IS_ERR(serial8250_isa_devs)) {
+ ret = PTR_ERR(serial8250_isa_devs);
+ goto unreg;
+ }
+
+ serial8250_register_ports(&serial8250_reg, &serial8250_isa_devs->dev);
+
+ ret = driver_register(&serial8250_isa_driver);
+ if (ret == 0)
+ goto out;
+
+ platform_device_unregister(serial8250_isa_devs);
+ unreg:
+ uart_unregister_driver(&serial8250_reg);
+ 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;
+
+ driver_unregister(&serial8250_isa_driver);
+ platform_device_unregister(isa_dev);
+
+ uart_unregister_driver(&serial8250_reg);
+}
+
+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 $Revision: 1.90 $");
+
+module_param(share_irqs, uint, 0644);
+MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices"
+ " (unsafe)");
+
+#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);
+
+/**
+ * register_serial - configure a 16x50 serial port at runtime
+ * @req: request structure
+ *
+ * Configure the serial port specified by the request. If the
+ * port exists and is in use an error is returned. If the port
+ * is not currently in the table it is added.
+ *
+ * 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 register_serial(struct serial_struct *req)
+{
+ struct uart_port port;
+
+ port.iobase = req->port;
+ port.membase = req->iomem_base;
+ port.irq = req->irq;
+ port.uartclk = req->baud_base * 16;
+ port.fifosize = req->xmit_fifo_size;
+ port.regshift = req->iomem_reg_shift;
+ port.iotype = req->io_type;
+ port.flags = req->flags | UPF_BOOT_AUTOCONF;
+ port.mapbase = req->iomap_base;
+ port.dev = NULL;
+
+ if (share_irqs)
+ port.flags |= UPF_SHARE_IRQ;
+
+ if (HIGH_BITS_OFFSET)
+ port.iobase |= (long) req->port_high << HIGH_BITS_OFFSET;
+
+ /*
+ * If a clock rate wasn't specified by the low level driver, then
+ * default to the standard clock rate. This should be 115200 (*16)
+ * and should not depend on the architecture's BASE_BAUD definition.
+ * However, since this API will be deprecated, it's probably a
+ * better idea to convert the drivers to use the new API
+ * (serial8250_register_port and serial8250_unregister_port).
+ */
+ if (port.uartclk == 0) {
+ printk(KERN_WARNING
+ "Serial: registering port at [%08x,%08lx,%p] irq %d with zero baud_base\n",
+ port.iobase, port.mapbase, port.membase, port.irq);
+ printk(KERN_WARNING "Serial: see %s:%d for more information\n",
+ __FILE__, __LINE__);
+ dump_stack();
+
+ /*
+ * Fix it up for now, but this is only a temporary measure.
+ */
+ port.uartclk = BASE_BAUD * 16;
+ }
+
+ return serial8250_register_port(&port);
+}
+EXPORT_SYMBOL(register_serial);
+
+/**
+ * unregister_serial - 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 our local PM control.
+ */
+void unregister_serial(int line)
+{
+ serial8250_unregister_port(line);
+}
+EXPORT_SYMBOL(unregister_serial);