1 /* linux/drivers/serial/s3c2412.c
2 *
3 * Driver for Samsung S3C2412 and S3C2413 SoC onboard UARTs.
4 *
5 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
6 * http://armlinux.simtec.co.uk/
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/module.h>
14 #include <linux/ioport.h>
15 #include <linux/io.h>
16 #include <linux/platform_device.h>
17 #include <linux/init.h>
18 #include <linux/serial_core.h>
19 #include <linux/serial.h>
20
21 #include <asm/irq.h>
22 #include <mach/hardware.h>
23
24 #include <plat/regs-serial.h>
25 #include <mach/regs-gpio.h>
26
27 #include "samsung.h"
28
s3c2412_serial_setsource(struct uart_port * port,struct s3c24xx_uart_clksrc * clk)29 static int s3c2412_serial_setsource(struct uart_port *port,
30 struct s3c24xx_uart_clksrc *clk)
31 {
32 unsigned long ucon = rd_regl(port, S3C2410_UCON);
33
34 ucon &= ~S3C2412_UCON_CLKMASK;
35
36 if (strcmp(clk->name, "uclk") == 0)
37 ucon |= S3C2440_UCON_UCLK;
38 else if (strcmp(clk->name, "pclk") == 0)
39 ucon |= S3C2440_UCON_PCLK;
40 else if (strcmp(clk->name, "usysclk") == 0)
41 ucon |= S3C2412_UCON_USYSCLK;
42 else {
43 printk(KERN_ERR "unknown clock source %s\n", clk->name);
44 return -EINVAL;
45 }
46
47 wr_regl(port, S3C2410_UCON, ucon);
48 return 0;
49 }
50
51
s3c2412_serial_getsource(struct uart_port * port,struct s3c24xx_uart_clksrc * clk)52 static int s3c2412_serial_getsource(struct uart_port *port,
53 struct s3c24xx_uart_clksrc *clk)
54 {
55 unsigned long ucon = rd_regl(port, S3C2410_UCON);
56
57 switch (ucon & S3C2412_UCON_CLKMASK) {
58 case S3C2412_UCON_UCLK:
59 clk->divisor = 1;
60 clk->name = "uclk";
61 break;
62
63 case S3C2412_UCON_PCLK:
64 case S3C2412_UCON_PCLK2:
65 clk->divisor = 1;
66 clk->name = "pclk";
67 break;
68
69 case S3C2412_UCON_USYSCLK:
70 clk->divisor = 1;
71 clk->name = "usysclk";
72 break;
73 }
74
75 return 0;
76 }
77
s3c2412_serial_resetport(struct uart_port * port,struct s3c2410_uartcfg * cfg)78 static int s3c2412_serial_resetport(struct uart_port *port,
79 struct s3c2410_uartcfg *cfg)
80 {
81 unsigned long ucon = rd_regl(port, S3C2410_UCON);
82
83 dbg("%s: port=%p (%08lx), cfg=%p\n",
84 __func__, port, port->mapbase, cfg);
85
86 /* ensure we don't change the clock settings... */
87
88 ucon &= S3C2412_UCON_CLKMASK;
89
90 wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
91 wr_regl(port, S3C2410_ULCON, cfg->ulcon);
92
93 /* reset both fifos */
94
95 wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
96 wr_regl(port, S3C2410_UFCON, cfg->ufcon);
97
98 return 0;
99 }
100
101 static struct s3c24xx_uart_info s3c2412_uart_inf = {
102 .name = "Samsung S3C2412 UART",
103 .type = PORT_S3C2412,
104 .fifosize = 64,
105 .has_divslot = 1,
106 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
107 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
108 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
109 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
110 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
111 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
112 .get_clksrc = s3c2412_serial_getsource,
113 .set_clksrc = s3c2412_serial_setsource,
114 .reset_port = s3c2412_serial_resetport,
115 };
116
117 /* device management */
118
s3c2412_serial_probe(struct platform_device * dev)119 static int s3c2412_serial_probe(struct platform_device *dev)
120 {
121 dbg("s3c2440_serial_probe: dev=%p\n", dev);
122 return s3c24xx_serial_probe(dev, &s3c2412_uart_inf);
123 }
124
125 static struct platform_driver s3c2412_serial_driver = {
126 .probe = s3c2412_serial_probe,
127 .remove = __devexit_p(s3c24xx_serial_remove),
128 .driver = {
129 .name = "s3c2412-uart",
130 .owner = THIS_MODULE,
131 },
132 };
133
134 s3c24xx_console_init(&s3c2412_serial_driver, &s3c2412_uart_inf);
135
s3c2412_serial_init(void)136 static inline int s3c2412_serial_init(void)
137 {
138 return s3c24xx_serial_init(&s3c2412_serial_driver, &s3c2412_uart_inf);
139 }
140
s3c2412_serial_exit(void)141 static inline void s3c2412_serial_exit(void)
142 {
143 platform_driver_unregister(&s3c2412_serial_driver);
144 }
145
146 module_init(s3c2412_serial_init);
147 module_exit(s3c2412_serial_exit);
148
149 MODULE_DESCRIPTION("Samsung S3C2412,S3C2413 SoC Serial port driver");
150 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
151 MODULE_LICENSE("GPL v2");
152 MODULE_ALIAS("platform:s3c2412-uart");
153