forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1296 lines
33 KiB
1296 lines
33 KiB
// SPDX-License-Identifier: GPL-2.0+ |
|
/* |
|
* 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 |
|
*/ |
|
|
|
#include <linux/acpi.h> |
|
#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; |
|
|
|
pr_debug("%s(%d): start\n", __func__, 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) |
|
break; |
|
} while (l != end); |
|
|
|
spin_unlock(&i->lock); |
|
|
|
pr_debug("%s(%d): end\n", __func__, irq); |
|
|
|
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; |
|
|
|
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); |
|
ret = request_irq(up->port.irq, serial8250_interrupt, |
|
up->port.irqflags, up->port.name, 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(struct timer_list *t) |
|
{ |
|
struct uart_8250_port *up = from_timer(up, t, timer); |
|
|
|
up->port.handle_irq(&up->port); |
|
mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port)); |
|
} |
|
|
|
static void serial8250_backup_timeout(struct timer_list *t) |
|
{ |
|
struct uart_8250_port *up = from_timer(up, t, timer); |
|
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("%s - using backup timer\n", port->name); |
|
|
|
up->timer.function = serial8250_backup_timeout; |
|
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) { |
|
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, |
|
u32 *capabilities); |
|
|
|
void serial8250_set_isa_configurator( |
|
void (*v)(int port, struct uart_port *up, u32 *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 inline void serial8250_apply_quirks(struct uart_8250_port *up) |
|
{ |
|
up->port.quirks |= skip_txen_test ? UPQ_NO_TXEN_TEST : 0; |
|
} |
|
|
|
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; |
|
|
|
timer_setup(&up->timer, serial8250_timeout, 0); |
|
|
|
up->ops = &univ8250_driver_ops; |
|
|
|
/* |
|
* ALPHA_KLUDGE_MCR needs to be killed. |
|
*/ |
|
up->mcr_mask = ~ALPHA_KLUDGE_MCR; |
|
up->mcr_force = ALPHA_KLUDGE_MCR; |
|
serial8250_set_defaults(up); |
|
} |
|
|
|
/* 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 = 0; |
|
port->uartclk = old_serial_port[i].baud_base * 16; |
|
port->flags = old_serial_port[i].flags; |
|
port->hub6 = 0; |
|
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; |
|
|
|
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; |
|
|
|
serial8250_apply_quirks(up); |
|
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; |
|
} |
|
|
|
static int univ8250_console_exit(struct console *co) |
|
{ |
|
struct uart_port *port; |
|
|
|
port = &serial8250_ports[co->index].port; |
|
return serial8250_console_exit(port); |
|
} |
|
|
|
/** |
|
* 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; |
|
resource_size_t 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, |
|
.exit = univ8250_console_exit, |
|
.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.has_sysrq = p->has_sysrq; |
|
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.set_ldisc = p->set_ldisc; |
|
uart.port.get_mctrl = p->get_mctrl; |
|
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; |
|
} |
|
|
|
static void serial_8250_overrun_backoff_work(struct work_struct *work) |
|
{ |
|
struct uart_8250_port *up = |
|
container_of(to_delayed_work(work), struct uart_8250_port, |
|
overrun_backoff); |
|
struct uart_port *port = &up->port; |
|
unsigned long flags; |
|
|
|
spin_lock_irqsave(&port->lock, flags); |
|
up->ier |= UART_IER_RLSI | UART_IER_RDI; |
|
up->port.read_status_mask |= UART_LSR_DR; |
|
serial_out(up, UART_IER, up->ier); |
|
spin_unlock_irqrestore(&port->lock, flags); |
|
} |
|
|
|
/** |
|
* 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) { |
|
struct mctrl_gpios *gpios; |
|
|
|
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->rs485_start_tx = up->rs485_start_tx; |
|
uart->rs485_stop_tx = up->rs485_stop_tx; |
|
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; |
|
ret = uart_get_rs485_mode(&uart->port); |
|
if (ret) |
|
goto err; |
|
} |
|
|
|
if (up->port.flags & UPF_FIXED_TYPE) |
|
uart->port.type = up->port.type; |
|
|
|
/* |
|
* Only call mctrl_gpio_init(), if the device has no ACPI |
|
* companion device |
|
*/ |
|
if (!has_acpi_companion(uart->port.dev)) { |
|
gpios = mctrl_gpio_init(&uart->port, 0); |
|
if (IS_ERR(gpios)) { |
|
ret = PTR_ERR(gpios); |
|
goto err; |
|
} else { |
|
uart->gpios = gpios; |
|
} |
|
} |
|
|
|
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_ldisc) |
|
uart->port.set_ldisc = up->port.set_ldisc; |
|
if (up->port.get_mctrl) |
|
uart->port.get_mctrl = up->port.get_mctrl; |
|
if (up->port.set_mctrl) |
|
uart->port.set_mctrl = up->port.set_mctrl; |
|
if (up->port.get_divisor) |
|
uart->port.get_divisor = up->port.get_divisor; |
|
if (up->port.set_divisor) |
|
uart->port.set_divisor = up->port.set_divisor; |
|
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); |
|
|
|
serial8250_apply_quirks(uart); |
|
ret = uart_add_one_port(&serial8250_reg, |
|
&uart->port); |
|
if (ret) |
|
goto err; |
|
|
|
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; |
|
} |
|
|
|
/* Initialise interrupt backoff work if required */ |
|
if (up->overrun_backoff_time_ms > 0) { |
|
uart->overrun_backoff_time_ms = |
|
up->overrun_backoff_time_ms; |
|
INIT_DELAYED_WORK(&uart->overrun_backoff, |
|
serial_8250_overrun_backoff_work); |
|
} else { |
|
uart->overrun_backoff_time_ms = 0; |
|
} |
|
} |
|
|
|
mutex_unlock(&serial_mutex); |
|
|
|
return ret; |
|
|
|
err: |
|
uart->port.dev = NULL; |
|
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; |
|
uart->port.type = PORT_UNKNOWN; |
|
uart->port.dev = &serial8250_isa_devs->dev; |
|
uart->capabilities = 0; |
|
serial8250_apply_quirks(uart); |
|
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_hw(share_irqs, uint, other, 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_hw_array(probe_rsa, ulong, ioport, &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
|
|
|