Merge commit 'v2.6.28-rc6' into core/debug
[linux-2.6] / arch / arm / mach-omap2 / serial.c
1 /*
2  * arch/arm/mach-omap2/serial.c
3  *
4  * OMAP2 serial support.
5  *
6  * Copyright (C) 2005-2008 Nokia Corporation
7  * Author: Paul Mundt <paul.mundt@nokia.com>
8  *
9  * Based off of arch/arm/mach-omap/omap1/serial.c
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License. See the file "COPYING" in the main directory of this archive
13  * for more details.
14  */
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/serial_8250.h>
18 #include <linux/serial_reg.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21
22 #include <mach/common.h>
23 #include <mach/board.h>
24
25 static struct clk *uart_ick[OMAP_MAX_NR_PORTS];
26 static struct clk *uart_fck[OMAP_MAX_NR_PORTS];
27
28 static struct plat_serial8250_port serial_platform_data[] = {
29         {
30                 .membase        = IO_ADDRESS(OMAP_UART1_BASE),
31                 .mapbase        = OMAP_UART1_BASE,
32                 .irq            = 72,
33                 .flags          = UPF_BOOT_AUTOCONF,
34                 .iotype         = UPIO_MEM,
35                 .regshift       = 2,
36                 .uartclk        = OMAP24XX_BASE_BAUD * 16,
37         }, {
38                 .membase        = IO_ADDRESS(OMAP_UART2_BASE),
39                 .mapbase        = OMAP_UART2_BASE,
40                 .irq            = 73,
41                 .flags          = UPF_BOOT_AUTOCONF,
42                 .iotype         = UPIO_MEM,
43                 .regshift       = 2,
44                 .uartclk        = OMAP24XX_BASE_BAUD * 16,
45         }, {
46                 .membase        = IO_ADDRESS(OMAP_UART3_BASE),
47                 .mapbase        = OMAP_UART3_BASE,
48                 .irq            = 74,
49                 .flags          = UPF_BOOT_AUTOCONF,
50                 .iotype         = UPIO_MEM,
51                 .regshift       = 2,
52                 .uartclk        = OMAP24XX_BASE_BAUD * 16,
53         }, {
54                 .flags          = 0
55         }
56 };
57
58 static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
59                                            int offset)
60 {
61         offset <<= up->regshift;
62         return (unsigned int)__raw_readb(up->membase + offset);
63 }
64
65 static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
66                                     int value)
67 {
68         offset <<= p->regshift;
69         __raw_writeb(value, p->membase + offset);
70 }
71
72 /*
73  * Internal UARTs need to be initialized for the 8250 autoconfig to work
74  * properly. Note that the TX watermark initialization may not be needed
75  * once the 8250.c watermark handling code is merged.
76  */
77 static inline void __init omap_serial_reset(struct plat_serial8250_port *p)
78 {
79         serial_write_reg(p, UART_OMAP_MDR1, 0x07);
80         serial_write_reg(p, UART_OMAP_SCR, 0x08);
81         serial_write_reg(p, UART_OMAP_MDR1, 0x00);
82         serial_write_reg(p, UART_OMAP_SYSC, (0x02 << 3) | (1 << 2) | (1 << 0));
83 }
84
85 void omap_serial_enable_clocks(int enable)
86 {
87         int i;
88         for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
89                 if (uart_ick[i] && uart_fck[i]) {
90                         if (enable) {
91                                 clk_enable(uart_ick[i]);
92                                 clk_enable(uart_fck[i]);
93                         } else {
94                                 clk_disable(uart_ick[i]);
95                                 clk_disable(uart_fck[i]);
96                         }
97                 }
98         }
99 }
100
101 void __init omap_serial_init(void)
102 {
103         int i;
104         const struct omap_uart_config *info;
105         char name[16];
106
107         /*
108          * Make sure the serial ports are muxed on at this point.
109          * You have to mux them off in device drivers later on
110          * if not needed.
111          */
112
113         info = omap_get_config(OMAP_TAG_UART, struct omap_uart_config);
114
115         if (info == NULL)
116                 return;
117
118         for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
119                 struct plat_serial8250_port *p = serial_platform_data + i;
120
121                 if (!(info->enabled_uarts & (1 << i))) {
122                         p->membase = NULL;
123                         p->mapbase = 0;
124                         continue;
125                 }
126
127                 sprintf(name, "uart%d_ick", i+1);
128                 uart_ick[i] = clk_get(NULL, name);
129                 if (IS_ERR(uart_ick[i])) {
130                         printk(KERN_ERR "Could not get uart%d_ick\n", i+1);
131                         uart_ick[i] = NULL;
132                 } else
133                         clk_enable(uart_ick[i]);
134
135                 sprintf(name, "uart%d_fck", i+1);
136                 uart_fck[i] = clk_get(NULL, name);
137                 if (IS_ERR(uart_fck[i])) {
138                         printk(KERN_ERR "Could not get uart%d_fck\n", i+1);
139                         uart_fck[i] = NULL;
140                 } else
141                         clk_enable(uart_fck[i]);
142
143                 omap_serial_reset(p);
144         }
145 }
146
147 static struct platform_device serial_device = {
148         .name                   = "serial8250",
149         .id                     = PLAT8250_DEV_PLATFORM,
150         .dev                    = {
151                 .platform_data  = serial_platform_data,
152         },
153 };
154
155 static int __init omap_init(void)
156 {
157         return platform_device_register(&serial_device);
158 }
159 arch_initcall(omap_init);