serial: Add support for Fintek F81216A LPC to 4 UART

This patch lets you set the RS485 cappabilites of the device through
TIOCSRS485 and TIOCGRS485 as defined on Documentation/serial/serial-rs485.txt

In order to probe the device, the PNP id and the device id is used.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ricardo Ribalda Delgado 2014-07-31 21:22:26 +02:00 committed by Greg Kroah-Hartman
parent e676253b19
commit 28e3fb6c4d
3 changed files with 259 additions and 0 deletions

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@ -0,0 +1,249 @@
/*
* Probe for F81216A LPC to 4 UART
*
* Based on drivers/tty/serial/8250_pnp.c, by Russell King, et al
*
* Copyright (C) 2014 Ricardo Ribalda, Qtechnology A/S
*
*
* 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.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/pnp.h>
#include <linux/kernel.h>
#include <linux/serial_core.h>
#include "8250.h"
#define ADDR_PORT 0x4E
#define DATA_PORT 0x4F
#define ENTRY_KEY 0x77
#define EXIT_KEY 0xAA
#define CHIP_ID1 0x20
#define CHIP_ID1_VAL 0x02
#define CHIP_ID2 0x21
#define CHIP_ID2_VAL 0x16
#define VENDOR_ID1 0x23
#define VENDOR_ID1_VAL 0x19
#define VENDOR_ID2 0x24
#define VENDOR_ID2_VAL 0x34
#define LDN 0x7
#define RS485 0xF0
#define RTS_INVERT BIT(5)
#define RS485_URA BIT(4)
#define RXW4C_IRA BIT(3)
#define TXW4C_IRA BIT(2)
#define DRIVER_NAME "8250_fintek"
static int fintek_8250_enter_key(void){
if (!request_muxed_region(ADDR_PORT, 2, DRIVER_NAME))
return -EBUSY;
outb(ENTRY_KEY, ADDR_PORT);
outb(ENTRY_KEY, ADDR_PORT);
return 0;
}
static void fintek_8250_exit_key(void){
outb(EXIT_KEY, ADDR_PORT);
release_region(ADDR_PORT, 2);
}
static int fintek_8250_get_index(resource_size_t base_addr)
{
resource_size_t base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
int i;
for (i = 0; i < ARRAY_SIZE(base); i++)
if (base_addr == base[i])
return i;
return -ENODEV;
}
static int fintek_8250_check_id(void)
{
outb(CHIP_ID1, ADDR_PORT);
if (inb(DATA_PORT) != CHIP_ID1_VAL)
return -ENODEV;
outb(CHIP_ID2, ADDR_PORT);
if (inb(DATA_PORT) != CHIP_ID2_VAL)
return -ENODEV;
outb(VENDOR_ID1, ADDR_PORT);
if (inb(DATA_PORT) != VENDOR_ID1_VAL)
return -ENODEV;
outb(VENDOR_ID2, ADDR_PORT);
if (inb(DATA_PORT) != VENDOR_ID2_VAL)
return -ENODEV;
return 0;
}
static int fintek_8250_rs4850_config(struct uart_8250_port *uart,
struct serial_rs485 *rs485)
{
uint8_t config = 0;
int index = fintek_8250_get_index(uart->port.iobase);
if (index < 0)
return -EINVAL;
if (rs485->flags & SER_RS485_ENABLED)
memset(rs485->padding, 0, sizeof(rs485->padding));
else
memset(rs485, 0, sizeof(*rs485));
rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
SER_RS485_RTS_AFTER_SEND;
if (rs485->delay_rts_before_send) {
rs485->delay_rts_before_send = 1;
config |= TXW4C_IRA;
}
if (rs485->delay_rts_after_send) {
rs485->delay_rts_after_send = 1;
config |= RXW4C_IRA;
}
if ((!!(rs485->flags & SER_RS485_RTS_ON_SEND)) ==
(!!(rs485->flags & SER_RS485_RTS_AFTER_SEND)))
rs485->flags &= SER_RS485_ENABLED;
else
config |= RS485_URA;
if (rs485->flags & SER_RS485_RTS_ON_SEND)
config |= RTS_INVERT;
if (fintek_8250_enter_key())
return -EBUSY;
outb(LDN, ADDR_PORT);
outb(index, DATA_PORT);
outb(RS485, ADDR_PORT);
outb(config, DATA_PORT);
fintek_8250_exit_key();
return 0;
}
static int
fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
{
int line;
struct uart_8250_port uart;
int ret;
if (!pnp_port_valid(dev, 0))
return -ENODEV;
if (fintek_8250_get_index(pnp_port_start(dev, 0)) < 0)
return -ENODEV;
/* Enable configuration registers*/
if (fintek_8250_enter_key())
return -EBUSY;
/*Check ID*/
ret = fintek_8250_check_id();
fintek_8250_exit_key();
if (ret)
return ret;
memset(&uart, 0, sizeof(uart));
if (!pnp_irq_valid(dev, 0))
return -ENODEV;
uart.port.irq = pnp_irq(dev, 0);
uart.port.iobase = pnp_port_start(dev, 0);
uart.port.iotype = UPIO_PORT;
uart.rs485_config = fintek_8250_rs4850_config;
uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
uart.port.flags |= UPF_SHARE_IRQ;
uart.port.uartclk = 1843200;
uart.port.dev = &dev->dev;
line = serial8250_register_8250_port(&uart);
if (line < 0)
return -ENODEV;
pnp_set_drvdata(dev, (void *)((long)line + 1));
return 0;
}
static void fintek_8250_remove(struct pnp_dev *dev)
{
long line = (long)pnp_get_drvdata(dev);
if (line)
serial8250_unregister_port(line - 1);
}
#ifdef CONFIG_PM
static int fintek_8250_suspend(struct pnp_dev *dev, pm_message_t state)
{
long line = (long)pnp_get_drvdata(dev);
if (!line)
return -ENODEV;
serial8250_suspend_port(line - 1);
return 0;
}
static int fintek_8250_resume(struct pnp_dev *dev)
{
long line = (long)pnp_get_drvdata(dev);
if (!line)
return -ENODEV;
serial8250_resume_port(line - 1);
return 0;
}
#else
#define fintek_8250_suspend NULL
#define fintek_8250_resume NULL
#endif /* CONFIG_PM */
static const struct pnp_device_id fintek_dev_table[] = {
/* Qtechnology Panel PC / IO1000 */
{ "PNP0501"},
{}
};
MODULE_DEVICE_TABLE(pnp, fintek_dev_table);
static struct pnp_driver fintek_8250_driver = {
.name = DRIVER_NAME,
.probe = fintek_8250_probe,
.remove = fintek_8250_remove,
.suspend = fintek_8250_suspend,
.resume = fintek_8250_resume,
.id_table = fintek_dev_table,
};
static int fintek_8250_init(void)
{
return pnp_register_driver(&fintek_8250_driver);
}
module_init(fintek_8250_init);
static void fintek_8250_exit(void)
{
pnp_unregister_driver(&fintek_8250_driver);
}
module_exit(fintek_8250_exit);
MODULE_DESCRIPTION("Fintek F812164 module");
MODULE_AUTHOR("Ricardo Ribalda <ricardo.ribalda@gmail.com>");
MODULE_LICENSE("GPL");

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@ -298,3 +298,12 @@ config SERIAL_8250_RT288X
If you have a Ralink RT288x/RT305x SoC based board and want to use the
serial port, say Y to this option. The driver can handle up to 2 serial
ports. If unsure, say N.
config SERIAL_8250_FINTEK
tristate "Support for Fintek F81216A LPC to 4 UART"
depends on SERIAL_8250 && PNP
help
Selecting this option will add support for the Fintek F81216A
LPC to 4 UART. This device has some RS485 functionality not available
through the PNP driver. If unsure, say N.

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@ -20,3 +20,4 @@ obj-$(CONFIG_SERIAL_8250_HUB6) += 8250_hub6.o
obj-$(CONFIG_SERIAL_8250_FSL) += 8250_fsl.o
obj-$(CONFIG_SERIAL_8250_DW) += 8250_dw.o
obj-$(CONFIG_SERIAL_8250_EM) += 8250_em.o
obj-$(CONFIG_SERIAL_8250_FINTEK) += 8250_fintek.o