| Rodolfo Giometti | 65131cd | 2008-11-12 13:27:14 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Silicon Labs C2 port Linux support for Eurotech Duramar 2150 |
| 3 | * |
| 4 | * Copyright (c) 2008 Rodolfo Giometti <giometti@linux.it> |
| 5 | * Copyright (c) 2008 Eurotech S.p.A. <info@eurotech.it> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms of the GNU General Public License version 2 as published by |
| 9 | * the Free Software Foundation |
| 10 | */ |
| 11 | |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/delay.h> |
| 17 | #include <linux/io.h> |
| 18 | #include <linux/c2port.h> |
| 19 | |
| 20 | #define DATA_PORT 0x325 |
| 21 | #define DIR_PORT 0x326 |
| 22 | #define C2D (1 << 0) |
| 23 | #define C2CK (1 << 1) |
| 24 | |
| 25 | static DEFINE_MUTEX(update_lock); |
| 26 | |
| 27 | /* |
| 28 | * C2 port operations |
| 29 | */ |
| 30 | |
| 31 | static void duramar2150_c2port_access(struct c2port_device *dev, int status) |
| 32 | { |
| 33 | u8 v; |
| 34 | |
| 35 | mutex_lock(&update_lock); |
| 36 | |
| 37 | v = inb(DIR_PORT); |
| 38 | |
| 39 | /* 0 = input, 1 = output */ |
| 40 | if (status) |
| 41 | outb(v | (C2D | C2CK), DIR_PORT); |
| 42 | else |
| 43 | /* When access is "off" is important that both lines are set |
| 44 | * as inputs or hi-impedence */ |
| 45 | outb(v & ~(C2D | C2CK), DIR_PORT); |
| 46 | |
| 47 | mutex_unlock(&update_lock); |
| 48 | } |
| 49 | |
| 50 | static void duramar2150_c2port_c2d_dir(struct c2port_device *dev, int dir) |
| 51 | { |
| 52 | u8 v; |
| 53 | |
| 54 | mutex_lock(&update_lock); |
| 55 | |
| 56 | v = inb(DIR_PORT); |
| 57 | |
| 58 | if (dir) |
| 59 | outb(v & ~C2D, DIR_PORT); |
| 60 | else |
| 61 | outb(v | C2D, DIR_PORT); |
| 62 | |
| 63 | mutex_unlock(&update_lock); |
| 64 | } |
| 65 | |
| 66 | static int duramar2150_c2port_c2d_get(struct c2port_device *dev) |
| 67 | { |
| 68 | return inb(DATA_PORT) & C2D; |
| 69 | } |
| 70 | |
| 71 | static void duramar2150_c2port_c2d_set(struct c2port_device *dev, int status) |
| 72 | { |
| 73 | u8 v; |
| 74 | |
| 75 | mutex_lock(&update_lock); |
| 76 | |
| 77 | v = inb(DATA_PORT); |
| 78 | |
| 79 | if (status) |
| 80 | outb(v | C2D, DATA_PORT); |
| 81 | else |
| 82 | outb(v & ~C2D, DATA_PORT); |
| 83 | |
| 84 | mutex_unlock(&update_lock); |
| 85 | } |
| 86 | |
| 87 | static void duramar2150_c2port_c2ck_set(struct c2port_device *dev, int status) |
| 88 | { |
| 89 | u8 v; |
| 90 | |
| 91 | mutex_lock(&update_lock); |
| 92 | |
| 93 | v = inb(DATA_PORT); |
| 94 | |
| 95 | if (status) |
| 96 | outb(v | C2CK, DATA_PORT); |
| 97 | else |
| 98 | outb(v & ~C2CK, DATA_PORT); |
| 99 | |
| 100 | mutex_unlock(&update_lock); |
| 101 | } |
| 102 | |
| 103 | static struct c2port_ops duramar2150_c2port_ops = { |
| 104 | .block_size = 512, /* bytes */ |
| 105 | .blocks_num = 30, /* total flash size: 15360 bytes */ |
| 106 | |
| 107 | .access = duramar2150_c2port_access, |
| 108 | .c2d_dir = duramar2150_c2port_c2d_dir, |
| 109 | .c2d_get = duramar2150_c2port_c2d_get, |
| 110 | .c2d_set = duramar2150_c2port_c2d_set, |
| 111 | .c2ck_set = duramar2150_c2port_c2ck_set, |
| 112 | }; |
| 113 | |
| 114 | static struct c2port_device *duramar2150_c2port_dev; |
| 115 | |
| 116 | /* |
| 117 | * Module stuff |
| 118 | */ |
| 119 | |
| 120 | static int __init duramar2150_c2port_init(void) |
| 121 | { |
| 122 | struct resource *res; |
| 123 | int ret = 0; |
| 124 | |
| 125 | res = request_region(0x325, 2, "c2port"); |
| 126 | if (!res) |
| 127 | return -EBUSY; |
| 128 | |
| 129 | duramar2150_c2port_dev = c2port_device_register("uc", |
| 130 | &duramar2150_c2port_ops, NULL); |
| 131 | if (!duramar2150_c2port_dev) { |
| 132 | ret = -ENODEV; |
| 133 | goto free_region; |
| 134 | } |
| 135 | |
| 136 | return 0; |
| 137 | |
| 138 | free_region: |
| 139 | release_region(0x325, 2); |
| 140 | return ret; |
| 141 | } |
| 142 | |
| 143 | static void __exit duramar2150_c2port_exit(void) |
| 144 | { |
| 145 | /* Setup the GPIOs as input by default (access = 0) */ |
| 146 | duramar2150_c2port_access(duramar2150_c2port_dev, 0); |
| 147 | |
| 148 | c2port_device_unregister(duramar2150_c2port_dev); |
| 149 | |
| 150 | release_region(0x325, 2); |
| 151 | } |
| 152 | |
| 153 | module_init(duramar2150_c2port_init); |
| 154 | module_exit(duramar2150_c2port_exit); |
| 155 | |
| 156 | MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); |
| 157 | MODULE_DESCRIPTION("Silicon Labs C2 port Linux support for Duramar 2150"); |
| 158 | MODULE_LICENSE("GPL"); |