linux/drivers/serial/s3c6400.c

153 lines
3.7 KiB
C

/* linux/drivers/serial/s3c6400.c
*
* Driver for Samsung S3C6400 and S3C6410 SoC onboard UARTs.
*
* Copyright 2008 Openmoko, Inc.
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <plat/regs-serial.h>
#include "samsung.h"
static int s3c6400_serial_setsource(struct uart_port *port,
struct s3c24xx_uart_clksrc *clk)
{
unsigned long ucon = rd_regl(port, S3C2410_UCON);
if (strcmp(clk->name, "uclk0") == 0) {
ucon &= ~S3C6400_UCON_CLKMASK;
ucon |= S3C6400_UCON_UCLK0;
} else if (strcmp(clk->name, "uclk1") == 0)
ucon |= S3C6400_UCON_UCLK1;
else if (strcmp(clk->name, "pclk") == 0) {
/* See notes about transitioning from UCLK to PCLK */
ucon &= ~S3C6400_UCON_UCLK0;
} else {
printk(KERN_ERR "unknown clock source %s\n", clk->name);
return -EINVAL;
}
wr_regl(port, S3C2410_UCON, ucon);
return 0;
}
static int s3c6400_serial_getsource(struct uart_port *port,
struct s3c24xx_uart_clksrc *clk)
{
u32 ucon = rd_regl(port, S3C2410_UCON);
clk->divisor = 1;
switch (ucon & S3C6400_UCON_CLKMASK) {
case S3C6400_UCON_UCLK0:
clk->name = "uclk0";
break;
case S3C6400_UCON_UCLK1:
clk->name = "uclk1";
break;
case S3C6400_UCON_PCLK:
case S3C6400_UCON_PCLK2:
clk->name = "pclk";
break;
}
return 0;
}
static int s3c6400_serial_resetport(struct uart_port *port,
struct s3c2410_uartcfg *cfg)
{
unsigned long ucon = rd_regl(port, S3C2410_UCON);
dbg("s3c6400_serial_resetport: port=%p (%08lx), cfg=%p\n",
port, port->mapbase, cfg);
/* ensure we don't change the clock settings... */
ucon &= S3C6400_UCON_CLKMASK;
wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
wr_regl(port, S3C2410_ULCON, cfg->ulcon);
/* reset both fifos */
wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
wr_regl(port, S3C2410_UFCON, cfg->ufcon);
return 0;
}
static struct s3c24xx_uart_info s3c6400_uart_inf = {
.name = "Samsung S3C6400 UART",
.type = PORT_S3C6400,
.fifosize = 64,
.has_divslot = 1,
.rx_fifomask = S3C2440_UFSTAT_RXMASK,
.rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
.rx_fifofull = S3C2440_UFSTAT_RXFULL,
.tx_fifofull = S3C2440_UFSTAT_TXFULL,
.tx_fifomask = S3C2440_UFSTAT_TXMASK,
.tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
.get_clksrc = s3c6400_serial_getsource,
.set_clksrc = s3c6400_serial_setsource,
.reset_port = s3c6400_serial_resetport,
};
/* device management */
static int s3c6400_serial_probe(struct platform_device *dev)
{
dbg("s3c6400_serial_probe: dev=%p\n", dev);
return s3c24xx_serial_probe(dev, &s3c6400_uart_inf);
}
static struct platform_driver s3c6400_serial_drv = {
.probe = s3c6400_serial_probe,
.remove = s3c24xx_serial_remove,
.driver = {
.name = "s3c6400-uart",
.owner = THIS_MODULE,
},
};
s3c24xx_console_init(&s3c6400_serial_drv, &s3c6400_uart_inf);
static int __init s3c6400_serial_init(void)
{
return s3c24xx_serial_init(&s3c6400_serial_drv, &s3c6400_uart_inf);
}
static void __exit s3c6400_serial_exit(void)
{
platform_driver_unregister(&s3c6400_serial_drv);
}
module_init(s3c6400_serial_init);
module_exit(s3c6400_serial_exit);
MODULE_DESCRIPTION("Samsung S3C6400,S3C6410 SoC Serial port driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:s3c6400-uart");