summaryrefslogtreecommitdiffstats
path: root/drivers/i2c/busses/i2c-hydra.c
blob: c527de17db4f25d8c539cefd2f3d2661b4e12fbf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/*
    i2c Support for the Apple `Hydra' Mac I/O

    Copyright (c) 1999-2004 Geert Uytterhoeven <geert@linux-m68k.org>

    Based on i2c Support for Via Technologies 82C586B South Bridge
    Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <linux/init.h>
#include <linux/io.h>
#include <asm/hydra.h>


#define HYDRA_CPD_PD0	0x00000001	/* CachePD lines */
#define HYDRA_CPD_PD1	0x00000002
#define HYDRA_CPD_PD2	0x00000004
#define HYDRA_CPD_PD3	0x00000008

#define HYDRA_SCLK	HYDRA_CPD_PD0
#define HYDRA_SDAT	HYDRA_CPD_PD1
#define HYDRA_SCLK_OE	0x00000010
#define HYDRA_SDAT_OE	0x00000020

static inline void pdregw(void *data, u32 val)
{
	struct Hydra *hydra = (struct Hydra *)data;
	writel(val, &hydra->CachePD);
}

static inline u32 pdregr(void *data)
{
	struct Hydra *hydra = (struct Hydra *)data;
	return readl(&hydra->CachePD);
}

static void hydra_bit_setscl(void *data, int state)
{
	u32 val = pdregr(data);
	if (state)
		val &= ~HYDRA_SCLK_OE;
	else {
		val &= ~HYDRA_SCLK;
		val |= HYDRA_SCLK_OE;
	}
	pdregw(data, val);
}

static void hydra_bit_setsda(void *data, int state)
{
	u32 val = pdregr(data);
	if (state)
		val &= ~HYDRA_SDAT_OE;
	else {
		val &= ~HYDRA_SDAT;
		val |= HYDRA_SDAT_OE;
	}
	pdregw(data, val);
}

static int hydra_bit_getscl(void *data)
{
	return (pdregr(data) & HYDRA_SCLK) != 0;
}

static int hydra_bit_getsda(void *data)
{
	return (pdregr(data) & HYDRA_SDAT) != 0;
}

/* ------------------------------------------------------------------------ */

static struct i2c_algo_bit_data hydra_bit_data = {
	.setsda		= hydra_bit_setsda,
	.setscl		= hydra_bit_setscl,
	.getsda		= hydra_bit_getsda,
	.getscl		= hydra_bit_getscl,
	.udelay		= 5,
	.timeout	= HZ
};

static struct i2c_adapter hydra_adap = {
	.owner		= THIS_MODULE,
	.name		= "Hydra i2c",
	.algo_data	= &hydra_bit_data,
};

static DEFINE_PCI_DEVICE_TABLE(hydra_ids) = {
	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_HYDRA) },
	{ 0, }
};

MODULE_DEVICE_TABLE (pci, hydra_ids);

static int __devinit hydra_probe(struct pci_dev *dev,
				 const struct pci_device_id *id)
{
	unsigned long base = pci_resource_start(dev, 0);
	int res;

	if (!request_mem_region(base+offsetof(struct Hydra, CachePD), 4,
				hydra_adap.name))
		return -EBUSY;

	hydra_bit_data.data = pci_ioremap_bar(dev, 0);
	if (hydra_bit_data.data == NULL) {
		release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
		return -ENODEV;
	}

	pdregw(hydra_bit_data.data, 0);		/* clear SCLK_OE and SDAT_OE */
	hydra_adap.dev.parent = &dev->dev;
	res = i2c_bit_add_bus(&hydra_adap);
	if (res < 0) {
		iounmap(hydra_bit_data.data);
		release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
		return res;
	}
	return 0;
}

static void __devexit hydra_remove(struct pci_dev *dev)
{
	pdregw(hydra_bit_data.data, 0);		/* clear SCLK_OE and SDAT_OE */
	i2c_del_adapter(&hydra_adap);
	iounmap(hydra_bit_data.data);
	release_mem_region(pci_resource_start(dev, 0)+
			   offsetof(struct Hydra, CachePD), 4);
}


static struct pci_driver hydra_driver = {
	.name		= "hydra_smbus",
	.id_table	= hydra_ids,
	.probe		= hydra_probe,
	.remove		= __devexit_p(hydra_remove),
};

static int __init i2c_hydra_init(void)
{
	return pci_register_driver(&hydra_driver);
}


static void __exit i2c_hydra_exit(void)
{
	pci_unregister_driver(&hydra_driver);
}



MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
MODULE_DESCRIPTION("i2c for Apple Hydra Mac I/O");
MODULE_LICENSE("GPL");

module_init(i2c_hydra_init);
module_exit(i2c_hydra_exit);

OpenPOWER on IntegriCloud