aboutsummaryrefslogtreecommitdiff
path: root/drivers/tty/serial/s3c2412.c
blob: 2234bf9ced45bc4fde8bcfba3d170ce69d229f34 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
/*
 * Driver for Samsung S3C2412 and S3C2413 SoC onboard UARTs.
 *
 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
 *	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 <mach/regs-gpio.h>

#include "samsung.h"

static int s3c2412_serial_setsource(struct uart_port *port,
				     struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	ucon &= ~S3C2412_UCON_CLKMASK;

	if (strcmp(clk->name, "uclk") == 0)
		ucon |= S3C2440_UCON_UCLK;
	else if (strcmp(clk->name, "pclk") == 0)
		ucon |= S3C2440_UCON_PCLK;
	else if (strcmp(clk->name, "usysclk") == 0)
		ucon |= S3C2412_UCON_USYSCLK;
	else {
		printk(KERN_ERR "unknown clock source %s\n", clk->name);
		return -EINVAL;
	}

	wr_regl(port, S3C2410_UCON, ucon);
	return 0;
}


static int s3c2412_serial_getsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	switch (ucon & S3C2412_UCON_CLKMASK) {
	case S3C2412_UCON_UCLK:
		clk->divisor = 1;
		clk->name = "uclk";
		break;

	case S3C2412_UCON_PCLK:
	case S3C2412_UCON_PCLK2:
		clk->divisor = 1;
		clk->name = "pclk";
		break;

	case S3C2412_UCON_USYSCLK:
		clk->divisor = 1;
		clk->name = "usysclk";
		break;
	}

	return 0;
}

static int s3c2412_serial_resetport(struct uart_port *port,
				    struct s3c2410_uartcfg *cfg)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	dbg("%s: port=%p (%08lx), cfg=%p\n",
	    __func__, port, port->mapbase, cfg);

	/* ensure we don't change the clock settings... */

	ucon &= S3C2412_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 s3c2412_uart_inf = {
	.name		= "Samsung S3C2412 UART",
	.type		= PORT_S3C2412,
	.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	= s3c2412_serial_getsource,
	.set_clksrc	= s3c2412_serial_setsource,
	.reset_port	= s3c2412_serial_resetport,
};

/* device management */

static int s3c2412_serial_probe(struct platform_device *dev)
{
	dbg("s3c2440_serial_probe: dev=%p\n", dev);
	return s3c24xx_serial_probe(dev, &s3c2412_uart_inf);
}

static struct platform_driver s3c2412_serial_driver = {
	.probe		= s3c2412_serial_probe,
	.remove		= __devexit_p(s3c24xx_serial_remove),
	.driver		= {
		.name	= "s3c2412-uart",
		.owner	= THIS_MODULE,
	},
};

static inline int s3c2412_serial_init(void)
{
	return s3c24xx_serial_init(&s3c2412_serial_driver, &s3c2412_uart_inf);
}

static inline void s3c2412_serial_exit(void)
{
	platform_driver_unregister(&s3c2412_serial_driver);
}

module_init(s3c2412_serial_init);
module_exit(s3c2412_serial_exit);

MODULE_DESCRIPTION("Samsung S3C2412,S3C2413 SoC Serial port driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:s3c2412-uart");