158 lines
3.5 KiB
C
158 lines
3.5 KiB
C
|
/*
|
||
|
* Simple CLPS711X serial driver
|
||
|
*
|
||
|
* (C) Copyright 2012 Alexander Shiyan <shc_work@mail.ru>
|
||
|
*
|
||
|
* 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 <common.h>
|
||
|
#include <malloc.h>
|
||
|
#include <init.h>
|
||
|
#include <io.h>
|
||
|
#include <linux/clk.h>
|
||
|
#include <linux/err.h>
|
||
|
|
||
|
#include <mach/clps711x.h>
|
||
|
|
||
|
struct clps711x_uart {
|
||
|
void __iomem *UBRLCR;
|
||
|
void __iomem *SYSCON;
|
||
|
void __iomem *SYSFLG;
|
||
|
void __iomem *UARTDR;
|
||
|
struct clk *uart_clk;
|
||
|
struct console_device cdev;
|
||
|
};
|
||
|
|
||
|
static int clps711x_setbaudrate(struct console_device *cdev, int baudrate)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
int divisor;
|
||
|
u32 tmp;
|
||
|
|
||
|
divisor = (clk_get_rate(s->uart_clk) / 16) / baudrate;
|
||
|
|
||
|
tmp = readl(s->UBRLCR) & ~UBRLCR_BAUD_MASK;
|
||
|
tmp |= divisor - 1;
|
||
|
writel(tmp, s->UBRLCR);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static void clps711x_init_port(struct console_device *cdev)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
u32 tmp;
|
||
|
|
||
|
/* Disable the UART */
|
||
|
writel(readl(s->SYSCON) & ~SYSCON_UARTEN, s->SYSCON);
|
||
|
|
||
|
/* Setup Line Control Register */
|
||
|
tmp = readl(s->UBRLCR) & UBRLCR_BAUD_MASK;
|
||
|
tmp |= UBRLCR_FIFOEN | UBRLCR_WRDLEN8; /* FIFO on, 8N1 mode */
|
||
|
writel(tmp, s->UBRLCR);
|
||
|
|
||
|
/* Set default baudrate on initialization */
|
||
|
clps711x_setbaudrate(cdev, CONFIG_BAUDRATE);
|
||
|
|
||
|
/* Enable the UART */
|
||
|
writel(readl(s->SYSCON) | SYSCON_UARTEN, s->SYSCON);
|
||
|
}
|
||
|
|
||
|
static void clps711x_putc(struct console_device *cdev, char c)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
|
||
|
/* Wait until there is space in the FIFO */
|
||
|
while (readl(s->SYSFLG) & SYSFLG_UTXFF)
|
||
|
barrier();
|
||
|
|
||
|
/* Send the character */
|
||
|
writew(c, s->UARTDR);
|
||
|
}
|
||
|
|
||
|
static int clps711x_getc(struct console_device *cdev)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
u16 data;
|
||
|
|
||
|
/* Wait until there is data in the FIFO */
|
||
|
while (readl(s->SYSFLG) & SYSFLG_URXFE)
|
||
|
barrier();
|
||
|
|
||
|
data = readw(s->UARTDR);
|
||
|
|
||
|
/* Check for an error flag */
|
||
|
if (data & (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR))
|
||
|
return -1;
|
||
|
|
||
|
return (int)data;
|
||
|
}
|
||
|
|
||
|
static int clps711x_tstc(struct console_device *cdev)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
|
||
|
return !(readl(s->SYSFLG) & SYSFLG_URXFE);
|
||
|
}
|
||
|
|
||
|
static void clps711x_flush(struct console_device *cdev)
|
||
|
{
|
||
|
struct clps711x_uart *s = cdev->dev->priv;
|
||
|
|
||
|
while (readl(s->SYSFLG) & SYSFLG_UBUSY)
|
||
|
barrier();
|
||
|
}
|
||
|
|
||
|
static int clps711x_probe(struct device_d *dev)
|
||
|
{
|
||
|
struct clps711x_uart *s;
|
||
|
|
||
|
BUG_ON(dev->num_resources != 4);
|
||
|
|
||
|
s = xzalloc(sizeof(struct clps711x_uart));
|
||
|
s->uart_clk = clk_get(dev, NULL);
|
||
|
BUG_ON(IS_ERR(s->uart_clk));
|
||
|
|
||
|
s->UBRLCR = dev_get_mem_region(dev, 0);
|
||
|
s->SYSCON = dev_get_mem_region(dev, 1);
|
||
|
s->SYSFLG = dev_get_mem_region(dev, 2);
|
||
|
s->UARTDR = dev_get_mem_region(dev, 3);
|
||
|
|
||
|
dev->priv = s;
|
||
|
s->cdev.dev = dev;
|
||
|
s->cdev.f_caps = CONSOLE_STDIN | CONSOLE_STDOUT | CONSOLE_STDERR;
|
||
|
s->cdev.tstc = clps711x_tstc;
|
||
|
s->cdev.putc = clps711x_putc;
|
||
|
s->cdev.getc = clps711x_getc;
|
||
|
s->cdev.flush = clps711x_flush;
|
||
|
s->cdev.setbrg = clps711x_setbaudrate;
|
||
|
clps711x_init_port(&s->cdev);
|
||
|
|
||
|
return console_register(&s->cdev);
|
||
|
}
|
||
|
|
||
|
static void clps711x_remove(struct device_d *dev)
|
||
|
{
|
||
|
struct clps711x_uart *s = dev->priv;
|
||
|
|
||
|
clps711x_flush(&s->cdev);
|
||
|
console_unregister(&s->cdev);
|
||
|
free(s);
|
||
|
}
|
||
|
|
||
|
static struct driver_d clps711x_driver = {
|
||
|
.name = "clps711x_serial",
|
||
|
.probe = clps711x_probe,
|
||
|
.remove = clps711x_remove,
|
||
|
};
|
||
|
|
||
|
static int clps711x_init(void)
|
||
|
{
|
||
|
return platform_driver_register(&clps711x_driver);
|
||
|
}
|
||
|
console_initcall(clps711x_init);
|