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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 420 | giacomo | 1 | /* ------------------------------------------------------------------------- */ |
| 2 | /* i2c-elv.c i2c-hw access for philips style parallel port adapters */ |
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| 3 | /* ------------------------------------------------------------------------- */ |
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| 4 | /* Copyright (C) 1995-2000 Simon G. Vogl |
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| 5 | |||
| 6 | This program is free software; you can redistribute it and/or modify |
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| 7 | it under the terms of the GNU General Public License as published by |
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| 8 | the Free Software Foundation; either version 2 of the License, or |
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| 9 | (at your option) any later version. |
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| 10 | |||
| 11 | This program is distributed in the hope that it will be useful, |
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| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 14 | GNU General Public License for more details. |
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| 15 | |||
| 16 | You should have received a copy of the GNU General Public License |
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| 17 | along with this program; if not, write to the Free Software |
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| 18 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
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| 19 | /* ------------------------------------------------------------------------- */ |
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| 20 | |||
| 21 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even |
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| 22 | Frodo Looijaard <frodol@dds.nl> */ |
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| 23 | |||
| 24 | #include <linux/kernel.h> |
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| 25 | #include <linux/module.h> |
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| 26 | #include <linux/delay.h> |
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| 27 | #include <linux/slab.h> |
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| 28 | #include <linux/init.h> |
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| 29 | #include <linux/ioport.h> |
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| 30 | #include <linux/errno.h> |
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| 31 | #include <linux/i2c.h> |
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| 32 | #include <linux/i2c-algo-bit.h> |
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| 33 | #include <asm/io.h> |
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| 34 | |||
| 35 | #define DEFAULT_BASE 0x378 |
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| 36 | static int base=0; |
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| 37 | static unsigned char port_data = 0; |
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| 38 | |||
| 39 | /* ----- global defines ----------------------------------------------- */ |
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| 40 | #define DEB(x) /* should be reasonable open, close &c. */ |
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| 41 | #define DEB2(x) /* low level debugging - very slow */ |
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| 42 | #define DEBE(x) x /* error messages */ |
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| 43 | #define DEBINIT(x) x /* detection status messages */ |
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| 44 | |||
| 45 | /* --- Convenience defines for the parallel port: */ |
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| 46 | #define BASE (unsigned int)(data) |
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| 47 | #define DATA BASE /* Centronics data port */ |
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| 48 | #define STAT (BASE+1) /* Centronics status port */ |
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| 49 | #define CTRL (BASE+2) /* Centronics control port */ |
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| 50 | |||
| 51 | |||
| 52 | /* ----- local functions ---------------------------------------------- */ |
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| 53 | |||
| 54 | |||
| 55 | static void bit_elv_setscl(void *data, int state) |
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| 56 | { |
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| 57 | if (state) { |
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| 58 | port_data &= 0xfe; |
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| 59 | } else { |
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| 60 | port_data |=1; |
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| 61 | } |
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| 62 | outb(port_data, DATA); |
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| 63 | } |
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| 64 | |||
| 65 | static void bit_elv_setsda(void *data, int state) |
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| 66 | { |
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| 67 | if (state) { |
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| 68 | port_data &=0xfd; |
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| 69 | } else { |
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| 70 | port_data |=2; |
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| 71 | } |
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| 72 | outb(port_data, DATA); |
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| 73 | } |
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| 74 | |||
| 75 | static int bit_elv_getscl(void *data) |
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| 76 | { |
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| 77 | return ( 0 == ( (inb_p(STAT)) & 0x08 ) ); |
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| 78 | } |
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| 79 | |||
| 80 | static int bit_elv_getsda(void *data) |
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| 81 | { |
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| 82 | return ( 0 == ( (inb_p(STAT)) & 0x40 ) ); |
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| 83 | } |
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| 84 | |||
| 85 | static int bit_elv_init(void) |
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| 86 | { |
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| 87 | if (!request_region(base, (base == 0x3bc) ? 3 : 8, |
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| 88 | "i2c (ELV adapter)")) |
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| 89 | return -ENODEV; |
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| 90 | |||
| 91 | if (inb(base+1) & 0x80) { /* BUSY should be high */ |
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| 92 | DEBINIT(printk(KERN_DEBUG "i2c-elv.o: Busy was low.\n")); |
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| 93 | goto fail; |
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| 94 | } |
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| 95 | |||
| 96 | outb(0x0c,base+2); /* SLCT auf low */ |
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| 97 | udelay(400); |
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| 98 | if (!(inb(base+1) && 0x10)) { |
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| 99 | outb(0x04,base+2); |
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| 100 | DEBINIT(printk(KERN_DEBUG "i2c-elv.o: Select was high.\n")); |
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| 101 | goto fail; |
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| 102 | } |
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| 103 | |||
| 104 | port_data = 0; |
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| 105 | bit_elv_setsda((void*)base,1); |
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| 106 | bit_elv_setscl((void*)base,1); |
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| 107 | return 0; |
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| 108 | |||
| 109 | fail: |
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| 110 | release_region(base , (base == 0x3bc) ? 3 : 8); |
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| 111 | return -ENODEV; |
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| 112 | } |
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| 113 | |||
| 114 | /* ------------------------------------------------------------------------ |
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| 115 | * Encapsulate the above functions in the correct operations structure. |
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| 116 | * This is only done when more than one hardware adapter is supported. |
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| 117 | */ |
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| 118 | static struct i2c_algo_bit_data bit_elv_data = { |
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| 119 | .setsda = bit_elv_setsda, |
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| 120 | .setscl = bit_elv_setscl, |
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| 121 | .getsda = bit_elv_getsda, |
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| 122 | .getscl = bit_elv_getscl, |
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| 123 | .udelay = 80, |
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| 124 | .mdelay = 80, |
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| 125 | .timeout = HZ |
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| 126 | }; |
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| 127 | |||
| 128 | static struct i2c_adapter bit_elv_ops = { |
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| 129 | .owner = THIS_MODULE, |
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| 130 | .algo_data = &bit_elv_data, |
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| 131 | .name = "ELV Parallel port adaptor", |
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| 132 | }; |
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| 133 | |||
| 134 | static int __init i2c_bitelv_init(void) |
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| 135 | { |
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| 136 | printk(KERN_INFO "i2c ELV parallel port adapter driver\n"); |
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| 137 | if (base==0) { |
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| 138 | /* probe some values */ |
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| 139 | base=DEFAULT_BASE; |
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| 140 | bit_elv_data.data=(void*)DEFAULT_BASE; |
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| 141 | if (bit_elv_init()==0) { |
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| 142 | if(i2c_bit_add_bus(&bit_elv_ops) < 0) |
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| 143 | return -ENODEV; |
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| 144 | } else { |
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| 145 | return -ENODEV; |
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| 146 | } |
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| 147 | } else { |
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| 148 | i2c_set_adapdata(&bit_elv_ops, (void *)base); |
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| 149 | if (bit_elv_init()==0) { |
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| 150 | if(i2c_bit_add_bus(&bit_elv_ops) < 0) |
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| 151 | return -ENODEV; |
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| 152 | } else { |
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| 153 | return -ENODEV; |
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| 154 | } |
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| 155 | } |
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| 156 | printk(KERN_DEBUG "i2c-elv.o: found device at %#x.\n",base); |
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| 157 | return 0; |
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| 158 | } |
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| 159 | |||
| 160 | static void __exit i2c_bitelv_exit(void) |
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| 161 | { |
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| 162 | i2c_bit_del_bus(&bit_elv_ops); |
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| 163 | release_region(base , (base == 0x3bc) ? 3 : 8); |
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| 164 | } |
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| 165 | |||
| 166 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
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| 167 | MODULE_DESCRIPTION("I2C-Bus adapter routines for ELV parallel port adapter"); |
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| 168 | MODULE_LICENSE("GPL"); |
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| 169 | |||
| 170 | MODULE_PARM(base, "i"); |
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| 171 | |||
| 172 | module_init(i2c_bitelv_init); |
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| 173 | module_exit(i2c_bitelv_exit); |