| /* |
| * Universal/legacy driver for 8250/16550-type serial ports |
| * |
| * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. |
| * |
| * Copyright (C) 2001 Russell King. |
| * |
| * Supports: ISA-compatible 8250/16550 ports |
| * PNP 8250/16550 ports |
| * early_serial_setup() ports |
| * userspace-configurable "phantom" ports |
| * "serial8250" platform devices |
| * serial8250_register_8250_port() ports |
| * |
| * 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. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/ioport.h> |
| #include <linux/init.h> |
| #include <linux/console.h> |
| #include <linux/sysrq.h> |
| #include <linux/delay.h> |
| #include <linux/platform_device.h> |
| #include <linux/tty.h> |
| #include <linux/ratelimit.h> |
| #include <linux/tty_flip.h> |
| #include <linux/serial.h> |
| #include <linux/serial_8250.h> |
| #include <linux/nmi.h> |
| #include <linux/mutex.h> |
| #include <linux/slab.h> |
| #include <linux/uaccess.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/io.h> |
| #ifdef CONFIG_SPARC |
| #include <linux/sunserialcore.h> |
| #endif |
| |
| #include <asm/irq.h> |
| |
| #include "8250.h" |
| |
| /* |
| * Configuration: |
| * share_irqs - whether we pass IRQF_SHARED to request_irq(). This option |
| * is unsafe when used on edge-triggered interrupts. |
| */ |
| static unsigned int share_irqs = SERIAL8250_SHARE_IRQS; |
| |
| static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS; |
| |
| static struct uart_driver serial8250_reg; |
| |
| static unsigned int skip_txen_test; /* force skip of txen test at init time */ |
| |
| #define PASS_LIMIT 512 |
| |
| #include <asm/serial.h> |
| /* |
| * SERIAL_PORT_DFNS tells us about built-in ports that have no |
| * standard enumeration mechanism. Platforms that can find all |
| * serial ports via mechanisms like ACPI or PCI need not supply it. |
| */ |
| #ifndef SERIAL_PORT_DFNS |
| #define SERIAL_PORT_DFNS |
| #endif |
| |
| static const struct old_serial_port old_serial_port[] = { |
| SERIAL_PORT_DFNS /* defined in asm/serial.h */ |
| }; |
| |
| #define UART_NR CONFIG_SERIAL_8250_NR_UARTS |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| |
| #define PORT_RSA_MAX 4 |
| static unsigned long probe_rsa[PORT_RSA_MAX]; |
| static unsigned int probe_rsa_count; |
| #endif /* CONFIG_SERIAL_8250_RSA */ |
| |
| struct irq_info { |
| struct hlist_node node; |
| int irq; |
| spinlock_t lock; /* Protects list not the hash */ |
| struct list_head *head; |
| }; |
| |
| #define NR_IRQ_HASH 32 /* Can be adjusted later */ |
| static struct hlist_head irq_lists[NR_IRQ_HASH]; |
| static DEFINE_MUTEX(hash_mutex); /* Used to walk the hash */ |
| |
| /* |
| * This is the serial driver's interrupt routine. |
| * |
| * Arjan thinks the old way was overly complex, so it got simplified. |
| * Alan disagrees, saying that need the complexity to handle the weird |
| * nature of ISA shared interrupts. (This is a special exception.) |
| * |
| * In order to handle ISA shared interrupts properly, we need to check |
| * that all ports have been serviced, and therefore the ISA interrupt |
| * line has been de-asserted. |
| * |
| * This means we need to loop through all ports. checking that they |
| * don't have an interrupt pending. |
| */ |
| static irqreturn_t serial8250_interrupt(int irq, void *dev_id) |
| { |
| struct irq_info *i = dev_id; |
| struct list_head *l, *end = NULL; |
| int pass_counter = 0, handled = 0; |
| |
| DEBUG_INTR("serial8250_interrupt(%d)...", irq); |
| |
| spin_lock(&i->lock); |
| |
| l = i->head; |
| do { |
| struct uart_8250_port *up; |
| struct uart_port *port; |
| |
| up = list_entry(l, struct uart_8250_port, list); |
| port = &up->port; |
| |
| if (port->handle_irq(port)) { |
| handled = 1; |
| end = NULL; |
| } else if (end == NULL) |
| end = l; |
| |
| l = l->next; |
| |
| if (l == i->head && pass_counter++ > PASS_LIMIT) { |
| /* If we hit this, we're dead. */ |
| printk_ratelimited(KERN_ERR |
| "serial8250: too much work for irq%d\n", irq); |
| break; |
| } |
| } while (l != end); |
| |
| spin_unlock(&i->lock); |
| |
| DEBUG_INTR("end.\n"); |
| |
| return IRQ_RETVAL(handled); |
| } |
| |
| /* |
| * To support ISA shared interrupts, we need to have one interrupt |
| * handler that ensures that the IRQ line has been deasserted |
| * before returning. Failing to do this will result in the IRQ |
| * line being stuck active, and, since ISA irqs are edge triggered, |
| * no more IRQs will be seen. |
| */ |
| static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up) |
| { |
| spin_lock_irq(&i->lock); |
| |
| if (!list_empty(i->head)) { |
| if (i->head == &up->list) |
| i->head = i->head->next; |
| list_del(&up->list); |
| } else { |
| BUG_ON(i->head != &up->list); |
| i->head = NULL; |
| } |
| spin_unlock_irq(&i->lock); |
| /* List empty so throw away the hash node */ |
| if (i->head == NULL) { |
| hlist_del(&i->node); |
| kfree(i); |
| } |
| } |
| |
| static int serial_link_irq_chain(struct uart_8250_port *up) |
| { |
| struct hlist_head *h; |
| struct hlist_node *n; |
| struct irq_info *i; |
| int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0; |
| |
| mutex_lock(&hash_mutex); |
| |
| h = &irq_lists[up->port.irq % NR_IRQ_HASH]; |
| |
| hlist_for_each(n, h) { |
| i = hlist_entry(n, struct irq_info, node); |
| if (i->irq == up->port.irq) |
| break; |
| } |
| |
| if (n == NULL) { |
| i = kzalloc(sizeof(struct irq_info), GFP_KERNEL); |
| if (i == NULL) { |
| mutex_unlock(&hash_mutex); |
| return -ENOMEM; |
| } |
| spin_lock_init(&i->lock); |
| i->irq = up->port.irq; |
| hlist_add_head(&i->node, h); |
| } |
| mutex_unlock(&hash_mutex); |
| |
| spin_lock_irq(&i->lock); |
| |
| if (i->head) { |
| list_add(&up->list, i->head); |
| spin_unlock_irq(&i->lock); |
| |
| ret = 0; |
| } else { |
| INIT_LIST_HEAD(&up->list); |
| i->head = &up->list; |
| spin_unlock_irq(&i->lock); |
| irq_flags |= up->port.irqflags; |
| ret = request_irq(up->port.irq, serial8250_interrupt, |
| irq_flags, "serial", i); |
| if (ret < 0) |
| serial_do_unlink(i, up); |
| } |
| |
| return ret; |
| } |
| |
| static void serial_unlink_irq_chain(struct uart_8250_port *up) |
| { |
| /* |
| * yes, some broken gcc emit "warning: 'i' may be used uninitialized" |
| * but no, we are not going to take a patch that assigns NULL below. |
| */ |
| struct irq_info *i; |
| struct hlist_node *n; |
| struct hlist_head *h; |
| |
| mutex_lock(&hash_mutex); |
| |
| h = &irq_lists[up->port.irq % NR_IRQ_HASH]; |
| |
| hlist_for_each(n, h) { |
| i = hlist_entry(n, struct irq_info, node); |
| if (i->irq == up->port.irq) |
| break; |
| } |
| |
| BUG_ON(n == NULL); |
| BUG_ON(i->head == NULL); |
| |
| if (list_empty(i->head)) |
| free_irq(up->port.irq, i); |
| |
| serial_do_unlink(i, up); |
| mutex_unlock(&hash_mutex); |
| } |
| |
| /* |
| * This function is used to handle ports that do not have an |
| * interrupt. This doesn't work very well for 16450's, but gives |
| * barely passable results for a 16550A. (Although at the expense |
| * of much CPU overhead). |
| */ |
| static void serial8250_timeout(unsigned long data) |
| { |
| struct uart_8250_port *up = (struct uart_8250_port *)data; |
| |
| up->port.handle_irq(&up->port); |
| mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port)); |
| } |
| |
| static void serial8250_backup_timeout(unsigned long data) |
| { |
| struct uart_8250_port *up = (struct uart_8250_port *)data; |
| unsigned int iir, ier = 0, lsr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&up->port.lock, flags); |
| |
| /* |
| * Must disable interrupts or else we risk racing with the interrupt |
| * based handler. |
| */ |
| if (up->port.irq) { |
| ier = serial_in(up, UART_IER); |
| serial_out(up, UART_IER, 0); |
| } |
| |
| iir = serial_in(up, UART_IIR); |
| |
| /* |
| * This should be a safe test for anyone who doesn't trust the |
| * IIR bits on their UART, but it's specifically designed for |
| * the "Diva" UART used on the management processor on many HP |
| * ia64 and parisc boxes. |
| */ |
| lsr = serial_in(up, UART_LSR); |
| up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; |
| if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) && |
| (!uart_circ_empty(&up->port.state->xmit) || up->port.x_char) && |
| (lsr & UART_LSR_THRE)) { |
| iir &= ~(UART_IIR_ID | UART_IIR_NO_INT); |
| iir |= UART_IIR_THRI; |
| } |
| |
| if (!(iir & UART_IIR_NO_INT)) |
| serial8250_tx_chars(up); |
| |
| if (up->port.irq) |
| serial_out(up, UART_IER, ier); |
| |
| spin_unlock_irqrestore(&up->port.lock, flags); |
| |
| /* Standard timer interval plus 0.2s to keep the port running */ |
| mod_timer(&up->timer, |
| jiffies + uart_poll_timeout(&up->port) + HZ / 5); |
| } |
| |
| static int univ8250_setup_irq(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| int retval = 0; |
| |
| /* |
| * The above check will only give an accurate result the first time |
| * the port is opened so this value needs to be preserved. |
| */ |
| if (up->bugs & UART_BUG_THRE) { |
| pr_debug("ttyS%d - using backup timer\n", serial_index(port)); |
| |
| up->timer.function = serial8250_backup_timeout; |
| up->timer.data = (unsigned long)up; |
| mod_timer(&up->timer, jiffies + |
| uart_poll_timeout(port) + HZ / 5); |
| } |
| |
| /* |
| * If the "interrupt" for this port doesn't correspond with any |
| * hardware interrupt, we use a timer-based system. The original |
| * driver used to do this with IRQ0. |
| */ |
| if (!port->irq) { |
| up->timer.data = (unsigned long)up; |
| mod_timer(&up->timer, jiffies + uart_poll_timeout(port)); |
| } else |
| retval = serial_link_irq_chain(up); |
| |
| return retval; |
| } |
| |
| static void univ8250_release_irq(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| |
| del_timer_sync(&up->timer); |
| up->timer.function = serial8250_timeout; |
| if (port->irq) |
| serial_unlink_irq_chain(up); |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| static int serial8250_request_rsa_resource(struct uart_8250_port *up) |
| { |
| unsigned long start = UART_RSA_BASE << up->port.regshift; |
| unsigned int size = 8 << up->port.regshift; |
| struct uart_port *port = &up->port; |
| int ret = -EINVAL; |
| |
| switch (port->iotype) { |
| case UPIO_HUB6: |
| case UPIO_PORT: |
| start += port->iobase; |
| if (request_region(start, size, "serial-rsa")) |
| ret = 0; |
| else |
| ret = -EBUSY; |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static void serial8250_release_rsa_resource(struct uart_8250_port *up) |
| { |
| unsigned long offset = UART_RSA_BASE << up->port.regshift; |
| unsigned int size = 8 << up->port.regshift; |
| struct uart_port *port = &up->port; |
| |
| switch (port->iotype) { |
| case UPIO_HUB6: |
| case UPIO_PORT: |
| release_region(port->iobase + offset, size); |
| break; |
| } |
| } |
| #endif |
| |
| static const struct uart_ops *base_ops; |
| static struct uart_ops univ8250_port_ops; |
| |
| static const struct uart_8250_ops univ8250_driver_ops = { |
| .setup_irq = univ8250_setup_irq, |
| .release_irq = univ8250_release_irq, |
| }; |
| |
| static struct uart_8250_port serial8250_ports[UART_NR]; |
| |
| /** |
| * serial8250_get_port - retrieve struct uart_8250_port |
| * @line: serial line number |
| * |
| * This function retrieves struct uart_8250_port for the specific line. |
| * This struct *must* *not* be used to perform a 8250 or serial core operation |
| * which is not accessible otherwise. Its only purpose is to make the struct |
| * accessible to the runtime-pm callbacks for context suspend/restore. |
| * The lock assumption made here is none because runtime-pm suspend/resume |
| * callbacks should not be invoked if there is any operation performed on the |
| * port. |
| */ |
| struct uart_8250_port *serial8250_get_port(int line) |
| { |
| return &serial8250_ports[line]; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_get_port); |
| |
| static void (*serial8250_isa_config)(int port, struct uart_port *up, |
| unsigned short *capabilities); |
| |
| void serial8250_set_isa_configurator( |
| void (*v)(int port, struct uart_port *up, unsigned short *capabilities)) |
| { |
| serial8250_isa_config = v; |
| } |
| EXPORT_SYMBOL(serial8250_set_isa_configurator); |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| |
| static void univ8250_config_port(struct uart_port *port, int flags) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| up->probe &= ~UART_PROBE_RSA; |
| if (port->type == PORT_RSA) { |
| if (serial8250_request_rsa_resource(up) == 0) |
| up->probe |= UART_PROBE_RSA; |
| } else if (flags & UART_CONFIG_TYPE) { |
| int i; |
| |
| for (i = 0; i < probe_rsa_count; i++) { |
| if (probe_rsa[i] == up->port.iobase) { |
| if (serial8250_request_rsa_resource(up) == 0) |
| up->probe |= UART_PROBE_RSA; |
| break; |
| } |
| } |
| } |
| |
| base_ops->config_port(port, flags); |
| |
| if (port->type != PORT_RSA && up->probe & UART_PROBE_RSA) |
| serial8250_release_rsa_resource(up); |
| } |
| |
| static int univ8250_request_port(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| int ret; |
| |
| ret = base_ops->request_port(port); |
| if (ret == 0 && port->type == PORT_RSA) { |
| ret = serial8250_request_rsa_resource(up); |
| if (ret < 0) |
| base_ops->release_port(port); |
| } |
| |
| return ret; |
| } |
| |
| static void univ8250_release_port(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| if (port->type == PORT_RSA) |
| serial8250_release_rsa_resource(up); |
| base_ops->release_port(port); |
| } |
| |
| static void univ8250_rsa_support(struct uart_ops *ops) |
| { |
| ops->config_port = univ8250_config_port; |
| ops->request_port = univ8250_request_port; |
| ops->release_port = univ8250_release_port; |
| } |
| |
| #else |
| #define univ8250_rsa_support(x) do { } while (0) |
| #endif /* CONFIG_SERIAL_8250_RSA */ |
| |
| static void __init serial8250_isa_init_ports(void) |
| { |
| struct uart_8250_port *up; |
| static int first = 1; |
| int i, irqflag = 0; |
| |
| if (!first) |
| return; |
| first = 0; |
| |
| if (nr_uarts > UART_NR) |
| nr_uarts = UART_NR; |
| |
| for (i = 0; i < nr_uarts; i++) { |
| struct uart_8250_port *up = &serial8250_ports[i]; |
| struct uart_port *port = &up->port; |
| |
| port->line = i; |
| serial8250_init_port(up); |
| if (!base_ops) |
| base_ops = port->ops; |
| port->ops = &univ8250_port_ops; |
| |
| init_timer(&up->timer); |
| up->timer.function = serial8250_timeout; |
| |
| up->ops = &univ8250_driver_ops; |
| |
| /* |
| * ALPHA_KLUDGE_MCR needs to be killed. |
| */ |
| up->mcr_mask = ~ALPHA_KLUDGE_MCR; |
| up->mcr_force = ALPHA_KLUDGE_MCR; |
| } |
| |
| /* chain base port ops to support Remote Supervisor Adapter */ |
| univ8250_port_ops = *base_ops; |
| univ8250_rsa_support(&univ8250_port_ops); |
| |
| if (share_irqs) |
| irqflag = IRQF_SHARED; |
| |
| for (i = 0, up = serial8250_ports; |
| i < ARRAY_SIZE(old_serial_port) && i < nr_uarts; |
| i++, up++) { |
| struct uart_port *port = &up->port; |
| |
| port->iobase = old_serial_port[i].port; |
| port->irq = irq_canonicalize(old_serial_port[i].irq); |
| port->irqflags = old_serial_port[i].irqflags; |
| port->uartclk = old_serial_port[i].baud_base * 16; |
| port->flags = old_serial_port[i].flags; |
| port->hub6 = old_serial_port[i].hub6; |
| port->membase = old_serial_port[i].iomem_base; |
| port->iotype = old_serial_port[i].io_type; |
| port->regshift = old_serial_port[i].iomem_reg_shift; |
| serial8250_set_defaults(up); |
| |
| port->irqflags |= irqflag; |
| if (serial8250_isa_config != NULL) |
| serial8250_isa_config(i, &up->port, &up->capabilities); |
| } |
| } |
| |
| static void __init |
| serial8250_register_ports(struct uart_driver *drv, struct device *dev) |
| { |
| int i; |
| |
| for (i = 0; i < nr_uarts; i++) { |
| struct uart_8250_port *up = &serial8250_ports[i]; |
| |
| if (up->port.type == PORT_8250_CIR) |
| continue; |
| |
| if (up->port.dev) |
| continue; |
| |
| up->port.dev = dev; |
| |
| if (skip_txen_test) |
| up->port.flags |= UPF_NO_TXEN_TEST; |
| |
| uart_add_one_port(drv, &up->port); |
| } |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_CONSOLE |
| |
| static void univ8250_console_write(struct console *co, const char *s, |
| unsigned int count) |
| { |
| struct uart_8250_port *up = &serial8250_ports[co->index]; |
| |
| serial8250_console_write(up, s, count); |
| } |
| |
| static int univ8250_console_setup(struct console *co, char *options) |
| { |
| struct uart_port *port; |
| int retval; |
| |
| /* |
| * 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; |
| /* link port to console */ |
| port->cons = co; |
| |
| retval = serial8250_console_setup(port, options, false); |
| if (retval != 0) |
| port->cons = NULL; |
| return retval; |
| } |
| |
| /** |
| * univ8250_console_match - non-standard console matching |
| * @co: registering console |
| * @name: name from console command line |
| * @idx: index from console command line |
| * @options: ptr to option string from console command line |
| * |
| * Only attempts to match console command lines of the form: |
| * console=uart[8250],io|mmio|mmio16|mmio32,<addr>[,<options>] |
| * console=uart[8250],0x<addr>[,<options>] |
| * This form is used to register an initial earlycon boot console and |
| * replace it with the serial8250_console at 8250 driver init. |
| * |
| * Performs console setup for a match (as required by interface) |
| * If no <options> are specified, then assume the h/w is already setup. |
| * |
| * Returns 0 if console matches; otherwise non-zero to use default matching |
| */ |
| static int univ8250_console_match(struct console *co, char *name, int idx, |
| char *options) |
| { |
| char match[] = "uart"; /* 8250-specific earlycon name */ |
| unsigned char iotype; |
| unsigned long addr; |
| int i; |
| |
| if (strncmp(name, match, 4) != 0) |
| return -ENODEV; |
| |
| if (uart_parse_earlycon(options, &iotype, &addr, &options)) |
| return -ENODEV; |
| |
| /* try to match the port specified on the command line */ |
| for (i = 0; i < nr_uarts; i++) { |
| struct uart_port *port = &serial8250_ports[i].port; |
| |
| if (port->iotype != iotype) |
| continue; |
| if ((iotype == UPIO_MEM || iotype == UPIO_MEM16 || |
| iotype == UPIO_MEM32 || iotype == UPIO_MEM32BE) |
| && (port->mapbase != addr)) |
| continue; |
| if (iotype == UPIO_PORT && port->iobase != addr) |
| continue; |
| |
| co->index = i; |
| port->cons = co; |
| return serial8250_console_setup(port, options, true); |
| } |
| |
| return -ENODEV; |
| } |
| |
| static struct console univ8250_console = { |
| .name = "ttyS", |
| .write = univ8250_console_write, |
| .device = uart_console_device, |
| .setup = univ8250_console_setup, |
| .match = univ8250_console_match, |
| .flags = CON_PRINTBUFFER | CON_ANYTIME, |
| .index = -1, |
| .data = &serial8250_reg, |
| }; |
| |
| static int __init univ8250_console_init(void) |
| { |
| if (nr_uarts == 0) |
| return -ENODEV; |
| |
| serial8250_isa_init_ports(); |
| register_console(&univ8250_console); |
| return 0; |
| } |
| console_initcall(univ8250_console_init); |
| |
| #define SERIAL8250_CONSOLE (&univ8250_console) |
| #else |
| #define SERIAL8250_CONSOLE NULL |
| #endif |
| |
| static struct uart_driver serial8250_reg = { |
| .owner = THIS_MODULE, |
| .driver_name = "serial", |
| .dev_name = "ttyS", |
| .major = TTY_MAJOR, |
| .minor = 64, |
| .cons = SERIAL8250_CONSOLE, |
| }; |
| |
| /* |
| * early_serial_setup - early registration for 8250 ports |
| * |
| * Setup an 8250 port structure prior to console initialisation. Use |
| * after console initialisation will cause undefined behaviour. |
| */ |
| int __init early_serial_setup(struct uart_port *port) |
| { |
| struct uart_port *p; |
| |
| if (port->line >= ARRAY_SIZE(serial8250_ports) || nr_uarts == 0) |
| return -ENODEV; |
| |
| serial8250_isa_init_ports(); |
| p = &serial8250_ports[port->line].port; |
| p->iobase = port->iobase; |
| p->membase = port->membase; |
| p->irq = port->irq; |
| p->irqflags = port->irqflags; |
| p->uartclk = port->uartclk; |
| p->fifosize = port->fifosize; |
| p->regshift = port->regshift; |
| p->iotype = port->iotype; |
| p->flags = port->flags; |
| p->mapbase = port->mapbase; |
| p->mapsize = port->mapsize; |
| p->private_data = port->private_data; |
| p->type = port->type; |
| p->line = port->line; |
| |
| serial8250_set_defaults(up_to_u8250p(p)); |
| |
| if (port->serial_in) |
| p->serial_in = port->serial_in; |
| if (port->serial_out) |
| p->serial_out = port->serial_out; |
| if (port->handle_irq) |
| p->handle_irq = port->handle_irq; |
| |
| return 0; |
| } |
| |
| /** |
| * serial8250_suspend_port - suspend one serial port |
| * @line: serial line number |
| * |
| * Suspend one serial port. |
| */ |
| void serial8250_suspend_port(int line) |
| { |
| struct uart_8250_port *up = &serial8250_ports[line]; |
| struct uart_port *port = &up->port; |
| |
| if (!console_suspend_enabled && uart_console(port) && |
| port->type != PORT_8250) { |
| unsigned char canary = 0xa5; |
| serial_out(up, UART_SCR, canary); |
| if (serial_in(up, UART_SCR) == canary) |
| up->canary = canary; |
| } |
| |
| uart_suspend_port(&serial8250_reg, port); |
| } |
| EXPORT_SYMBOL(serial8250_suspend_port); |
| |
| /** |
| * serial8250_resume_port - resume one serial port |
| * @line: serial line number |
| * |
| * Resume one serial port. |
| */ |
| void serial8250_resume_port(int line) |
| { |
| struct uart_8250_port *up = &serial8250_ports[line]; |
| struct uart_port *port = &up->port; |
| |
| up->canary = 0; |
| |
| if (up->capabilities & UART_NATSEMI) { |
| /* Ensure it's still in high speed mode */ |
| serial_port_out(port, UART_LCR, 0xE0); |
| |
| ns16550a_goto_highspeed(up); |
| |
| serial_port_out(port, UART_LCR, 0); |
| port->uartclk = 921600*16; |
| } |
| uart_resume_port(&serial8250_reg, port); |
| } |
| EXPORT_SYMBOL(serial8250_resume_port); |
| |
| /* |
| * Register a set of serial devices attached to a platform device. The |
| * list is terminated with a zero flags entry, which means we expect |
| * all entries to have at least UPF_BOOT_AUTOCONF set. |
| */ |
| static int serial8250_probe(struct platform_device *dev) |
| { |
| struct plat_serial8250_port *p = dev_get_platdata(&dev->dev); |
| struct uart_8250_port uart; |
| int ret, i, irqflag = 0; |
| |
| memset(&uart, 0, sizeof(uart)); |
| |
| if (share_irqs) |
| irqflag = IRQF_SHARED; |
| |
| for (i = 0; p && p->flags != 0; p++, i++) { |
| uart.port.iobase = p->iobase; |
| uart.port.membase = p->membase; |
| uart.port.irq = p->irq; |
| uart.port.irqflags = p->irqflags; |
| uart.port.uartclk = p->uartclk; |
| uart.port.regshift = p->regshift; |
| uart.port.iotype = p->iotype; |
| uart.port.flags = p->flags; |
| uart.port.mapbase = p->mapbase; |
| uart.port.hub6 = p->hub6; |
| uart.port.private_data = p->private_data; |
| uart.port.type = p->type; |
| uart.port.serial_in = p->serial_in; |
| uart.port.serial_out = p->serial_out; |
| uart.port.handle_irq = p->handle_irq; |
| uart.port.handle_break = p->handle_break; |
| uart.port.set_termios = p->set_termios; |
| uart.port.pm = p->pm; |
| uart.port.dev = &dev->dev; |
| uart.port.irqflags |= irqflag; |
| ret = serial8250_register_8250_port(&uart); |
| if (ret < 0) { |
| dev_err(&dev->dev, "unable to register port at index %d " |
| "(IO%lx MEM%llx IRQ%d): %d\n", i, |
| p->iobase, (unsigned long long)p->mapbase, |
| p->irq, ret); |
| } |
| } |
| return 0; |
| } |
| |
| /* |
| * Remove serial ports registered against a platform device. |
| */ |
| static int serial8250_remove(struct platform_device *dev) |
| { |
| int i; |
| |
| for (i = 0; i < nr_uarts; i++) { |
| struct uart_8250_port *up = &serial8250_ports[i]; |
| |
| if (up->port.dev == &dev->dev) |
| serial8250_unregister_port(i); |
| } |
| return 0; |
| } |
| |
| static int serial8250_suspend(struct platform_device *dev, pm_message_t state) |
| { |
| int i; |
| |
| for (i = 0; i < UART_NR; i++) { |
| struct uart_8250_port *up = &serial8250_ports[i]; |
| |
| if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev) |
| uart_suspend_port(&serial8250_reg, &up->port); |
| } |
| |
| return 0; |
| } |
| |
| static int serial8250_resume(struct platform_device *dev) |
| { |
| int i; |
| |
| for (i = 0; i < UART_NR; i++) { |
| struct uart_8250_port *up = &serial8250_ports[i]; |
| |
| if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev) |
| serial8250_resume_port(i); |
| } |
| |
| return 0; |
| } |
| |
| static struct platform_driver serial8250_isa_driver = { |
| .probe = serial8250_probe, |
| .remove = serial8250_remove, |
| .suspend = serial8250_suspend, |
| .resume = serial8250_resume, |
| .driver = { |
| .name = "serial8250", |
| }, |
| }; |
| |
| /* |
| * This "device" covers _all_ ISA 8250-compatible serial devices listed |
| * in the table in include/asm/serial.h |
| */ |
| static struct platform_device *serial8250_isa_devs; |
| |
| /* |
| * serial8250_register_8250_port and serial8250_unregister_port allows for |
| * 16x50 serial ports to be configured at run-time, to support PCMCIA |
| * modems and PCI multiport cards. |
| */ |
| static DEFINE_MUTEX(serial_mutex); |
| |
| static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *port) |
| { |
| int i; |
| |
| /* |
| * First, find a port entry which matches. |
| */ |
| for (i = 0; i < nr_uarts; i++) |
| if (uart_match_port(&serial8250_ports[i].port, port)) |
| return &serial8250_ports[i]; |
| |
| /* try line number first if still available */ |
| i = port->line; |
| if (i < nr_uarts && serial8250_ports[i].port.type == PORT_UNKNOWN && |
| serial8250_ports[i].port.iobase == 0) |
| 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_8250_port - register a serial port |
| * @up: serial port template |
| * |
| * Configure the serial port specified by the request. If the |
| * port exists and is in use, it is hung up and unregistered |
| * first. |
| * |
| * The port is then probed and if necessary the IRQ is autodetected |
| * If this fails an error is returned. |
| * |
| * On success the port is ready to use and the line number is returned. |
| */ |
| int serial8250_register_8250_port(struct uart_8250_port *up) |
| { |
| struct uart_8250_port *uart; |
| int ret = -ENOSPC; |
| |
| if (up->port.uartclk == 0) |
| return -EINVAL; |
| |
| mutex_lock(&serial_mutex); |
| |
| uart = serial8250_find_match_or_unused(&up->port); |
| if (uart && uart->port.type != PORT_8250_CIR) { |
| if (uart->port.dev) |
| uart_remove_one_port(&serial8250_reg, &uart->port); |
| |
| uart->port.iobase = up->port.iobase; |
| uart->port.membase = up->port.membase; |
| uart->port.irq = up->port.irq; |
| uart->port.irqflags = up->port.irqflags; |
| uart->port.uartclk = up->port.uartclk; |
| uart->port.fifosize = up->port.fifosize; |
| uart->port.regshift = up->port.regshift; |
| uart->port.iotype = up->port.iotype; |
| uart->port.flags = up->port.flags | UPF_BOOT_AUTOCONF; |
| uart->bugs = up->bugs; |
| uart->port.mapbase = up->port.mapbase; |
| uart->port.mapsize = up->port.mapsize; |
| uart->port.private_data = up->port.private_data; |
| uart->tx_loadsz = up->tx_loadsz; |
| uart->capabilities = up->capabilities; |
| uart->port.throttle = up->port.throttle; |
| uart->port.unthrottle = up->port.unthrottle; |
| uart->port.rs485_config = up->port.rs485_config; |
| uart->port.rs485 = up->port.rs485; |
| uart->dma = up->dma; |
| |
| /* Take tx_loadsz from fifosize if it wasn't set separately */ |
| if (uart->port.fifosize && !uart->tx_loadsz) |
| uart->tx_loadsz = uart->port.fifosize; |
| |
| if (up->port.dev) |
| uart->port.dev = up->port.dev; |
| |
| if (skip_txen_test) |
| uart->port.flags |= UPF_NO_TXEN_TEST; |
| |
| if (up->port.flags & UPF_FIXED_TYPE) |
| uart->port.type = up->port.type; |
| |
| serial8250_set_defaults(uart); |
| |
| /* Possibly override default I/O functions. */ |
| if (up->port.serial_in) |
| uart->port.serial_in = up->port.serial_in; |
| if (up->port.serial_out) |
| uart->port.serial_out = up->port.serial_out; |
| if (up->port.handle_irq) |
| uart->port.handle_irq = up->port.handle_irq; |
| /* Possibly override set_termios call */ |
| if (up->port.set_termios) |
| uart->port.set_termios = up->port.set_termios; |
| if (up->port.set_mctrl) |
| uart->port.set_mctrl = up->port.set_mctrl; |
| if (up->port.startup) |
| uart->port.startup = up->port.startup; |
| if (up->port.shutdown) |
| uart->port.shutdown = up->port.shutdown; |
| if (up->port.pm) |
| uart->port.pm = up->port.pm; |
| if (up->port.handle_break) |
| uart->port.handle_break = up->port.handle_break; |
| if (up->dl_read) |
| uart->dl_read = up->dl_read; |
| if (up->dl_write) |
| uart->dl_write = up->dl_write; |
| |
| if (uart->port.type != PORT_8250_CIR) { |
| if (serial8250_isa_config != NULL) |
| serial8250_isa_config(0, &uart->port, |
| &uart->capabilities); |
| |
| ret = uart_add_one_port(&serial8250_reg, |
| &uart->port); |
| if (ret == 0) |
| ret = uart->port.line; |
| } else { |
| dev_info(uart->port.dev, |
| "skipping CIR port at 0x%lx / 0x%llx, IRQ %d\n", |
| uart->port.iobase, |
| (unsigned long long)uart->port.mapbase, |
| uart->port.irq); |
| |
| ret = 0; |
| } |
| } |
| mutex_unlock(&serial_mutex); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(serial8250_register_8250_port); |
| |
| /** |
| * serial8250_unregister_port - remove a 16x50 serial port at runtime |
| * @line: serial line number |
| * |
| * Remove one serial port. This may not be called from interrupt |
| * context. We hand the port back to the our control. |
| */ |
| void serial8250_unregister_port(int line) |
| { |
| struct uart_8250_port *uart = &serial8250_ports[line]; |
| |
| mutex_lock(&serial_mutex); |
| |
| if (uart->em485) { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&uart->port.lock, flags); |
| serial8250_em485_destroy(uart); |
| spin_unlock_irqrestore(&uart->port.lock, flags); |
| } |
| |
| uart_remove_one_port(&serial8250_reg, &uart->port); |
| if (serial8250_isa_devs) { |
| uart->port.flags &= ~UPF_BOOT_AUTOCONF; |
| if (skip_txen_test) |
| uart->port.flags |= UPF_NO_TXEN_TEST; |
| uart->port.type = PORT_UNKNOWN; |
| uart->port.dev = &serial8250_isa_devs->dev; |
| uart->capabilities = 0; |
| 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; |
| |
| if (nr_uarts == 0) |
| return -ENODEV; |
| |
| serial8250_isa_init_ports(); |
| |
| pr_info("Serial: 8250/16550 driver, %d ports, IRQ sharing %sabled\n", |
| nr_uarts, share_irqs ? "en" : "dis"); |
| |
| #ifdef CONFIG_SPARC |
| ret = sunserial_register_minors(&serial8250_reg, UART_NR); |
| #else |
| serial8250_reg.nr = UART_NR; |
| ret = uart_register_driver(&serial8250_reg); |
| #endif |
| if (ret) |
| goto out; |
| |
| ret = serial8250_pnp_init(); |
| if (ret) |
| goto unreg_uart_drv; |
| |
| serial8250_isa_devs = platform_device_alloc("serial8250", |
| PLAT8250_DEV_LEGACY); |
| if (!serial8250_isa_devs) { |
| ret = -ENOMEM; |
| goto unreg_pnp; |
| } |
| |
| ret = platform_device_add(serial8250_isa_devs); |
| if (ret) |
| goto put_dev; |
| |
| serial8250_register_ports(&serial8250_reg, &serial8250_isa_devs->dev); |
| |
| ret = platform_driver_register(&serial8250_isa_driver); |
| if (ret == 0) |
| goto out; |
| |
| platform_device_del(serial8250_isa_devs); |
| put_dev: |
| platform_device_put(serial8250_isa_devs); |
| unreg_pnp: |
| serial8250_pnp_exit(); |
| unreg_uart_drv: |
| #ifdef CONFIG_SPARC |
| sunserial_unregister_minors(&serial8250_reg, UART_NR); |
| #else |
| uart_unregister_driver(&serial8250_reg); |
| #endif |
| out: |
| return ret; |
| } |
| |
| static void __exit serial8250_exit(void) |
| { |
| struct platform_device *isa_dev = serial8250_isa_devs; |
| |
| /* |
| * This tells serial8250_unregister_port() not to re-register |
| * the ports (thereby making serial8250_isa_driver permanently |
| * in use.) |
| */ |
| serial8250_isa_devs = NULL; |
| |
| platform_driver_unregister(&serial8250_isa_driver); |
| platform_device_unregister(isa_dev); |
| |
| serial8250_pnp_exit(); |
| |
| #ifdef CONFIG_SPARC |
| sunserial_unregister_minors(&serial8250_reg, UART_NR); |
| #else |
| uart_unregister_driver(&serial8250_reg); |
| #endif |
| } |
| |
| module_init(serial8250_init); |
| module_exit(serial8250_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("Generic 8250/16x50 serial driver"); |
| |
| module_param(share_irqs, uint, 0644); |
| MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices (unsafe)"); |
| |
| module_param(nr_uarts, uint, 0644); |
| MODULE_PARM_DESC(nr_uarts, "Maximum number of UARTs supported. (1-" __MODULE_STRING(CONFIG_SERIAL_8250_NR_UARTS) ")"); |
| |
| module_param(skip_txen_test, uint, 0644); |
| MODULE_PARM_DESC(skip_txen_test, "Skip checking for the TXEN bug at init time"); |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444); |
| MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA"); |
| #endif |
| MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR); |
| |
| #ifdef CONFIG_SERIAL_8250_DEPRECATED_OPTIONS |
| #ifndef MODULE |
| /* This module was renamed to 8250_core in 3.7. Keep the old "8250" name |
| * working as well for the module options so we don't break people. We |
| * need to keep the names identical and the convenient macros will happily |
| * refuse to let us do that by failing the build with redefinition errors |
| * of global variables. So we stick them inside a dummy function to avoid |
| * those conflicts. The options still get parsed, and the redefined |
| * MODULE_PARAM_PREFIX lets us keep the "8250." syntax alive. |
| * |
| * This is hacky. I'm sorry. |
| */ |
| static void __used s8250_options(void) |
| { |
| #undef MODULE_PARAM_PREFIX |
| #define MODULE_PARAM_PREFIX "8250_core." |
| |
| module_param_cb(share_irqs, ¶m_ops_uint, &share_irqs, 0644); |
| module_param_cb(nr_uarts, ¶m_ops_uint, &nr_uarts, 0644); |
| module_param_cb(skip_txen_test, ¶m_ops_uint, &skip_txen_test, 0644); |
| #ifdef CONFIG_SERIAL_8250_RSA |
| __module_param_call(MODULE_PARAM_PREFIX, probe_rsa, |
| ¶m_array_ops, .arr = &__param_arr_probe_rsa, |
| 0444, -1, 0); |
| #endif |
| } |
| #else |
| MODULE_ALIAS("8250_core"); |
| #endif |
| #endif |