1 /***************************************************************************
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
10 * Copyright (C) 2006 by Linus Nielsen Feltzing
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
18 * KIND, either express or implied.
20 ****************************************************************************/
26 #include "generic_i2c.h"
28 #define MAX_I2C_INTERFACES 5
30 static int i2c_num_ifs
= 0;
31 static const struct i2c_interface
*i2c_if
[MAX_I2C_INTERFACES
];
33 static void i2c_start(const struct i2c_interface
*iface
)
40 iface
->delay_hd_sta();
44 static void i2c_stop(const struct i2c_interface
*iface
)
50 iface
->delay_su_sto();
54 static void i2c_ack(const struct i2c_interface
*iface
, bool ack
)
63 iface
->delay_su_dat();
69 static int i2c_getack(const struct i2c_interface
*iface
)
74 iface
->delay_su_dat();
78 ret
= 0; /* ack failed */
84 iface
->delay_hd_dat();
88 static unsigned char i2c_inb(const struct i2c_interface
*iface
, bool ack
)
91 unsigned char byte
= 0;
95 /* clock in each bit, MSB first */
96 for ( i
=0x80; i
; i
>>=1 ) {
102 iface
->delay_hd_dat();
110 static int i2c_outb(const struct i2c_interface
*iface
, unsigned char byte
)
116 /* clock out each bit, MSB first */
117 for (i
=0x80; i
; i
>>=1) {
122 iface
->delay_su_dat();
124 iface
->delay_thigh();
126 iface
->delay_hd_dat();
131 return i2c_getack(iface
);
134 int i2c_write_data(int bus_index
, int bus_address
, int address
,
135 const unsigned char* buf
, int count
)
139 const struct i2c_interface
*iface
= i2c_if
[bus_index
];
142 if (!i2c_outb(iface
, bus_address
& 0xfe))
150 if (!i2c_outb(iface
, address
))
157 for(i
= 0;i
< count
;i
++)
159 if (!i2c_outb(iface
, buf
[i
]))
171 int i2c_read_data(int bus_index
, int bus_address
, int address
,
172 unsigned char* buf
, int count
)
176 const struct i2c_interface
*iface
= i2c_if
[bus_index
];
181 if (!i2c_outb(iface
, bus_address
& 0xfe))
186 if (!i2c_outb(iface
, address
))
194 if (!i2c_outb(iface
, bus_address
| 1))
200 for(i
= 0;i
< count
-1;i
++)
201 buf
[i
] = i2c_inb(iface
, true);
203 buf
[i
] = i2c_inb(iface
, false);
210 /* returns bus index which can be used as a handle, or <0 on error */
211 int i2c_add_node(const struct i2c_interface
*iface
)
215 if (i2c_num_ifs
== MAX_I2C_INTERFACES
)
218 bus_index
= i2c_num_ifs
++;
219 i2c_if
[bus_index
] = iface
;