| /* |
| * 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. |
| */ |
| |
| #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/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 <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; |
| |
| /* |
| * 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) |
| |
| #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 uart_8250_port { |
| struct uart_port port; |
| struct timer_list timer; /* "no irq" timer */ |
| struct list_head list; /* ports on this IRQ */ |
| unsigned short capabilities; /* port capabilities */ |
| unsigned short bugs; /* port bugs */ |
| unsigned int tx_loadsz; /* transmit fifo load size */ |
| 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, |
| }, |
| }; |
| |
| #ifdef CONFIG_SERIAL_8250_AU1X00 |
| |
| /* Au1x00 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, |
| }; |
| |
| /* sane hardware needs no mapping */ |
| static inline int map_8250_in_reg(struct uart_8250_port *up, int offset) |
| { |
| if (up->port.iotype != UPIO_AU) |
| return offset; |
| return au_io_in_map[offset]; |
| } |
| |
| static inline int map_8250_out_reg(struct uart_8250_port *up, int offset) |
| { |
| if (up->port.iotype != UPIO_AU) |
| return offset; |
| return au_io_out_map[offset]; |
| } |
| |
| #else |
| |
| /* sane hardware needs no mapping */ |
| #define map_8250_in_reg(up, offset) (offset) |
| #define map_8250_out_reg(up, offset) (offset) |
| |
| #endif |
| |
| static unsigned int serial_in(struct uart_8250_port *up, int offset) |
| { |
| unsigned int tmp; |
| offset = map_8250_in_reg(up, 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); |
| |
| #ifdef CONFIG_SERIAL_8250_AU1X00 |
| case UPIO_AU: |
| return __raw_readl(up->port.membase + offset); |
| #endif |
| |
| case UPIO_TSI: |
| if (offset == UART_IIR) { |
| tmp = readl(up->port.membase + (UART_IIR & ~3)); |
| return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */ |
| } else |
| return readb(up->port.membase + offset); |
| |
| default: |
| return inb(up->port.iobase + offset); |
| } |
| } |
| |
| static void |
| serial_out(struct uart_8250_port *up, int offset, int value) |
| { |
| offset = map_8250_out_reg(up, 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; |
| |
| #ifdef CONFIG_SERIAL_8250_AU1X00 |
| case UPIO_AU: |
| __raw_writel(value, up->port.membase + offset); |
| break; |
| #endif |
| case UPIO_TSI: |
| if (!((offset == UART_IER) && (value & UART_IER_UUE))) |
| writeb(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) |
| |
| /* Uart divisor latch read */ |
| static inline int _serial_dl_read(struct uart_8250_port *up) |
| { |
| return serial_inp(up, UART_DLL) | serial_inp(up, UART_DLM) << 8; |
| } |
| |
| /* Uart divisor latch write */ |
| static inline void _serial_dl_write(struct uart_8250_port *up, int value) |
| { |
| serial_outp(up, UART_DLL, value & 0xff); |
| serial_outp(up, UART_DLM, value >> 8 & 0xff); |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_AU1X00 |
| /* Au1x00 haven't got a standard divisor latch */ |
| static int serial_dl_read(struct uart_8250_port *up) |
| { |
| if (up->port.iotype == UPIO_AU) |
| return __raw_readl(up->port.membase + 0x28); |
| else |
| return _serial_dl_read(up); |
| } |
| |
| static void serial_dl_write(struct uart_8250_port *up, int value) |
| { |
| if (up->port.iotype == UPIO_AU) |
| __raw_writel(value, up->port.membase + 0x28); |
| else |
| _serial_dl_write(up, value); |
| } |
| #else |
| #define serial_dl_read(up) _serial_dl_read(up) |
| #define serial_dl_write(up, value) _serial_dl_write(up, value) |
| #endif |
| |
| /* |
| * 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_lcr; |
| unsigned short old_dl; |
| 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_dl = serial_dl_read(up); |
| serial_dl_write(up, 0x0001); |
| 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_dl_write(up, old_dl); |
| 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; |
| |
| /* |
| * 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_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 |
| */ |
| 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) { |
| unsigned short quot; |
| |
| serial_outp(up, UART_LCR, 0xE0); |
| |
| quot = serial_dl_read(up); |
| quot <<= 3; |
| |
| 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_dl_write(up, quot); |
| |
| serial_outp(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_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; |
| up->bugs = 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 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_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 |
| |
| #ifdef CONFIG_SERIAL_8250_AU1X00 |
| /* if access method is AU, it is a 16550 with a quirk */ |
| if (up->port.type == PORT_16550A && up->port.iotype == UPIO_AU) |
| up->bugs |= UART_BUG_NOMSR; |
| #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); |
| if (up->capabilities & UART_CAP_UUE) |
| serial_outp(up, UART_IER, UART_IER_UUE); |
| else |
| 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 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 = (struct uart_8250_port *)port; |
| |
| __stop_tx(up); |
| |
| /* |
| * We really want to stop the transmitter from sending. |
| */ |
| if (up->port.type == PORT_16C950) { |
| up->acr |= UART_ACR_TXDIS; |
| serial_icr_write(up, UART_ACR, up->acr); |
| } |
| } |
| |
| static void transmit_chars(struct uart_8250_port *up); |
| |
| static void serial8250_start_tx(struct uart_port *port) |
| { |
| 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); |
| |
| if (up->bugs & UART_BUG_TXEN) { |
| unsigned char lsr, iir; |
| lsr = serial_in(up, UART_LSR); |
| iir = serial_in(up, UART_IIR); |
| if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) |
| transmit_chars(up); |
| } |
| } |
| |
| /* |
| * Re-enable the transmitter if we disabled it. |
| */ |
| if (up->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 = (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; |
| |
| /* no MSR capabilities */ |
| if (up->bugs & UART_BUG_NOMSR) |
| return; |
| |
| up->ier |= UART_IER_MSI; |
| serial_out(up, UART_IER, up->ier); |
| } |
| |
| static 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 { |
| 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 ignored. |
| */ |
| 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; |
| |
| uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag); |
| |
| 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 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_tx_stopped(&up->port)) { |
| serial8250_stop_tx(&up->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); |
| 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)) |
| __stop_tx(up); |
| } |
| |
| static unsigned int check_modem_status(struct uart_8250_port *up) |
| { |
| unsigned int status = serial_in(up, UART_MSR); |
| |
| if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI) { |
| if (status & UART_MSR_TERI) |
| up->port.icount.rng++; |
| if (status & UART_MSR_DDSR) |
| up->port.icount.dsr++; |
| if (status & UART_MSR_DDCD) |
| uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); |
| if (status & UART_MSR_DCTS) |
| uart_handle_cts_change(&up->port, status & UART_MSR_CTS); |
| |
| wake_up_interruptible(&up->port.info->delta_msr_wait); |
| } |
| |
| return status; |
| } |
| |
| /* |
| * 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; |
| |
| spin_lock(&up->port.lock); |
| |
| 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); |
| |
| spin_unlock(&up->port.lock); |
| } |
| |
| /* |
| * 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)) { |
| serial8250_handle_port(up, regs); |
| |
| 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 ? IRQF_SHARED : 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)) |
| serial8250_handle_port(up, NULL); |
| |
| 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 int status; |
| unsigned int ret; |
| |
| status = check_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 = (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; |
| unsigned char lsr, iir; |
| 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 reenabled 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); |
| |
| /* |
| * Do a quick test to see if we receive an |
| * interrupt when we enable the TX irq. |
| */ |
| serial_outp(up, UART_IER, UART_IER_THRI); |
| lsr = serial_in(up, UART_LSR); |
| iir = serial_in(up, UART_IIR); |
| serial_outp(up, 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", |
| port->line); |
| } |
| } else { |
| up->bugs &= ~UART_BUG_TXEN; |
| } |
| |
| 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 = 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 (!(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); |
| |
| /* |
| * Oxford Semi 952 rev B workaround |
| */ |
| if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0) |
| 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 (!(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 | 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_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 (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_AU: |
| size = 0x100000; |
| /* fall thru */ |
| 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_AU: |
| size = 0x100000; |
| /* fall thru */ |
| 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; |
| |
| /* |
| * 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 < nr_uarts; 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 < nr_uarts; |
| 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 < nr_uarts; 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, int bits) |
| { |
| 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 & bits) != bits); |
| |
| /* 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); |
| } |
| } |
| |
| static void serial8250_console_putchar(struct uart_port *port, int ch) |
| { |
| struct uart_8250_port *up = (struct uart_8250_port *)port; |
| |
| wait_for_xmitr(up, UART_LSR_THRE); |
| serial_out(up, 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]; |
| unsigned long flags; |
| unsigned int ier; |
| int locked = 1; |
| |
| touch_nmi_watchdog(); |
| |
| local_irq_save(flags); |
| if (up->port.sysrq) { |
| /* serial8250_handle_port() already took the lock */ |
| locked = 0; |
| } else if (oops_in_progress) { |
| locked = spin_trylock(&up->port.lock); |
| } else |
| spin_lock(&up->port.lock); |
| |
| /* |
| * First save the IER 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); |
| |
| uart_console_write(&up->port, s, count, serial8250_console_putchar); |
| |
| /* |
| * Finally, wait for transmitter to become empty |
| * and restore the IER |
| */ |
| wait_for_xmitr(up, BOTH_EMPTY); |
| serial_out(up, UART_IER, ier); |
| |
| if (locked) |
| spin_unlock(&up->port.lock); |
| local_irq_restore(flags); |
| } |
| |
| 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 >= nr_uarts) |
| 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 < nr_uarts; line++) { |
| port = &serial8250_ports[line].port; |
| if (uart_match_port(p, port)) |
| 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", |
| .dev_name = "ttyS", |
| .major = TTY_MAJOR, |
| .minor = 64, |
| .nr = UART_NR, |
| .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) |
| { |
| 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 platform_device *dev) |
| { |
| struct plat_serial8250_port *p = dev->dev.platform_data; |
| struct uart_port port; |
| int ret, i; |
| |
| memset(&port, 0, sizeof(struct uart_port)); |
| |
| for (i = 0; p && p->flags != 0; p++, i++) { |
| 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.hub6 = p->hub6; |
| port.dev = &dev->dev; |
| if (share_irqs) |
| port.flags |= UPF_SHARE_IRQ; |
| ret = serial8250_register_port(&port); |
| if (ret < 0) { |
| dev_err(&dev->dev, "unable to register port at index %d " |
| "(IO%lx MEM%lx IRQ%d): %d\n", i, |
| p->iobase, p->mapbase, p->irq, ret); |
| } |
| } |
| return 0; |
| } |
| |
| /* |
| * Remove serial ports registered against a platform device. |
| */ |
| static int __devexit serial8250_remove(struct platform_device *dev) |
| { |
| int i; |
| |
| for (i = 0; i < nr_uarts; 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) |
| uart_resume_port(&serial8250_reg, &up->port); |
| } |
| |
| return 0; |
| } |
| |
| static struct platform_driver serial8250_isa_driver = { |
| .probe = serial8250_probe, |
| .remove = __devexit_p(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_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++) |
| 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++) |
| 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 < nr_uarts; 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; |
| |
| mutex_lock(&serial_mutex); |
| |
| 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; |
| } |
| mutex_unlock(&serial_mutex); |
| |
| 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]; |
| |
| 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_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, i; |
| |
| if (nr_uarts > UART_NR) |
| nr_uarts = UART_NR; |
| |
| printk(KERN_INFO "Serial: 8250/16550 driver $Revision: 1.90 $ " |
| "%d ports, IRQ sharing %sabled\n", nr_uarts, |
| 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_alloc("serial8250", |
| PLAT8250_DEV_LEGACY); |
| if (!serial8250_isa_devs) { |
| ret = -ENOMEM; |
| goto unreg_uart_drv; |
| } |
| |
| ret = platform_device_add(serial8250_isa_devs); |
| if (ret) |
| goto put_dev; |
| |
| serial8250_register_ports(&serial8250_reg, &serial8250_isa_devs->dev); |
| |
| ret = platform_driver_register(&serial8250_isa_driver); |
| if (ret == 0) |
| goto out; |
| |
| platform_device_del(serial8250_isa_devs); |
| put_dev: |
| platform_device_put(serial8250_isa_devs); |
| unreg_uart_drv: |
| 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; |
| |
| platform_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)"); |
| |
| module_param(nr_uarts, uint, 0644); |
| MODULE_PARM_DESC(nr_uarts, "Maximum number of UARTs supported. (1-" __MODULE_STRING(CONFIG_SERIAL_8250_NR_UARTS) ")"); |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444); |
| MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA"); |
| #endif |
| MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR); |