// SPDX-License-Identifier: GPL-2.0+
/*
* Universal/legacy platform driver for 8250/16550-type serial ports
*
* Supports:
* ISA-compatible 8250/16550 ports
* ACPI 8250/16550 ports
* PNP 8250/16550 ports
* "serial8250" platform devices
*/
#include <linux/acpi.h>
#include <linux/array_size.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/once.h>
#include <linux/platform_device.h>
#include <linux/serial_8250.h>
#ifdef CONFIG_SPARC
#include <linux/sunserialcore.h>
#endif
#include "8250.h"
/*
* Configuration:
* share_irqs: Whether we pass IRQF_SHARED to request_irq().
* This option is unsafe when used on edge-triggered interrupts.
* skip_txen_test: Force skip of txen test at init time.
*/
unsigned int share_irqs = SERIAL8250_SHARE_IRQS;
unsigned int skip_txen_test;
unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS;
#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 */
};
serial8250_isa_config_fn serial8250_isa_config;
void serial8250_set_isa_configurator(serial8250_isa_config_fn v)
{
serial8250_isa_config = v;
}
EXPORT_SYMBOL(serial8250_set_isa_configurator);
static void __init __serial8250_isa_init_ports(void)
{
int i, irqflag = 0;
if (nr_uarts > UART_NR)
nr_uarts = UART_NR;
/*
* Set up initial ISA ports based on nr_uart module param, or else
* default to CONFIG_SERIAL_8250_RUNTIME_UARTS. Note that we do not
* need to increase nr_uarts when setting up the initial ISA ports.
*/
for (i = 0; i < nr_uarts; i++)
serial8250_setup_port(i);
/* chain base port ops to support Remote Supervisor Adapter */
univ8250_port_ops = *univ8250_port_base_ops;
univ8250_rsa_support(&univ8250_port_ops);
if (share_irqs)
irqflag = IRQF_SHARED;
for (i = 0; i < ARRAY_SIZE(old_serial_port) && i < nr_uarts; i++) {
struct uart_8250_port *up = serial8250_get_port(i);
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);
}
}
void __init serial8250_isa_init_ports(void)
{
DO_ONCE(__serial8250_isa_init_ports);
}
/*
* Generic 16550A platform devices
*/
static int serial8250_probe_acpi(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct uart_8250_port uart = { };
struct resource *regs;
unsigned char iotype;
int ret, line;
regs = platform_get_mem_or_io(pdev, 0);
if (!regs)
return dev_err_probe(dev, -EINVAL, "no registers defined\n");
switch (resource_type(regs)) {
case IORESOURCE_IO:
uart.port.iobase = regs->start;
iotype = UPIO_PORT;
break;
case IORESOURCE_MEM:
uart.port.mapbase = regs->start;
uart.port.mapsize = resource_size(regs);
uart.port.flags = UPF_IOREMAP;
iotype = UPIO_MEM;
break;
default:
return -EINVAL;
}
/* default clock frequency */
uart.port.uartclk = 1843200;
uart.port.type = PORT_16550A;
uart.port.dev = &pdev->dev;
uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
ret = uart_read_and_validate_port_properties(&uart.port);
/* no interrupt -> fall back to polling */
if (ret == -ENXIO)
ret = 0;
if (ret)
return ret;
/*
* The previous call may not set iotype correctly when reg-io-width
* property is absent and it doesn't support IO port resource.
*/
uart.port.iotype = iotype;
line = serial8250_register_8250_port(&uart);
if (line < 0)
return line;
return 0;
}
static int serial8250_probe_platform(struct platform_device *dev, struct plat_serial8250_port *p)
{
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.mapsize = p->mapsize;
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.bugs = p->bugs;
uart.port.serial_in = p->serial_in;
uart.port.serial_out = p->serial_out;
uart.dl_read = p->dl_read;
uart.dl_write = p->dl_write;
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;
}
/*
* 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 *pdev)
{
struct device *dev = &pdev->dev;
struct plat_serial8250_port *p;
p = dev_get_platdata(dev);
if (p)
return serial8250_probe_platform(pdev, p);
/*
* Probe platform UART devices defined using standard hardware
* discovery mechanism like ACPI or DT. Support only ACPI based
* serial device for now.
*/
if (has_acpi_companion(dev))
return serial8250_probe_acpi(pdev);
return 0;
}
/*
* Remove serial ports registered against a platform device.
*/
static void serial8250_remove(struct platform_device *dev)
{
int i;
for (i = 0; i < nr_uarts; i++) {
struct uart_8250_port *up = serial8250_get_port(i);
if (up->port.dev == &dev->dev)
serial8250_unregister_port(i);
}
}
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_get_port(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_get_port(i);
if (up->port.type != PORT_UNKNOWN && up->port.dev == &dev->dev)
serial8250_resume_port(i);
}
return 0;
}
static const struct acpi_device_id acpi_platform_serial_table[] = {
{ "RSCV0003" }, /* RISC-V Generic 16550A UART */
{ }
};
MODULE_DEVICE_TABLE(acpi, acpi_platform_serial_table);
static struct platform_driver serial8250_isa_driver = {
.probe = serial8250_probe,
.remove_new = serial8250_remove,
.suspend = serial8250_suspend,
.resume = serial8250_resume,
.driver = {
.name = "serial8250",
.acpi_match_table = acpi_platform_serial_table,
},
};
/*
* This "device" covers _all_ ISA 8250-compatible serial devices listed
* in the table in include/asm/serial.h.
*/
struct platform_device *serial8250_isa_devs;
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 %s\n",
nr_uarts, str_enabled_disabled(share_irqs));
#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;
}
module_init(serial8250_init);
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_exit(serial8250_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic 8250/16x50 serial platform 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");
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);
}
#else
MODULE_ALIAS("8250_core");
#endif
#endif
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