aboutsummaryrefslogtreecommitdiff
path: root/drivers/w1/matrox_w1.c
blob: e565416458eadce0d2425e7e63c025cece6f35a7 (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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
/*
 * 	matrox_w1.c
 *
 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 * 
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <asm/atomic.h>
#include <asm/types.h>
#include <asm/io.h>

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/pci_ids.h>
#include <linux/pci.h>
#include <linux/timer.h>

#include "w1.h"
#include "w1_int.h"
#include "w1_log.h"

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire prtocol) over VGA DDC(matrox gpio).");

static struct pci_device_id matrox_w1_tbl[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) },
	{ },
};
MODULE_DEVICE_TABLE(pci, matrox_w1_tbl);

static int __devinit matrox_w1_probe(struct pci_dev *, const struct pci_device_id *);
static void __devexit matrox_w1_remove(struct pci_dev *);

static struct pci_driver matrox_w1_pci_driver = {
	.name = "matrox_w1",
	.id_table = matrox_w1_tbl,
	.probe = matrox_w1_probe,
	.remove = __devexit_p(matrox_w1_remove),
};

/* 
 * Matrox G400 DDC registers.
 */

#define MATROX_G400_DDC_CLK		(1<<4)
#define MATROX_G400_DDC_DATA		(1<<1)

#define MATROX_BASE			0x3C00
#define MATROX_STATUS			0x1e14

#define MATROX_PORT_INDEX_OFFSET	0x00
#define MATROX_PORT_DATA_OFFSET		0x0A

#define MATROX_GET_CONTROL		0x2A
#define MATROX_GET_DATA			0x2B
#define MATROX_CURSOR_CTL		0x06

struct matrox_device
{
	void __iomem *base_addr;
	void __iomem *port_index;
	void __iomem *port_data;
	u8 data_mask;

	unsigned long phys_addr;
	void __iomem *virt_addr;
	unsigned long found;

	struct w1_bus_master *bus_master;
};

static u8 matrox_w1_read_ddc_bit(unsigned long);
static void matrox_w1_write_ddc_bit(unsigned long, u8);

/*
 * These functions read and write DDC Data bit.
 *
 * Using tristate pins, since i can't find any open-drain pin in whole motherboard.
 * Unfortunately we can't connect to Intel's 82801xx IO controller
 * since we don't know motherboard schema, wich has pretty unused(may be not) GPIO.
 *
 * I've heard that PIIX also has open drain pin.
 *
 * Port mapping.
 */
static __inline__ u8 matrox_w1_read_reg(struct matrox_device *dev, u8 reg)
{
	u8 ret;

	writeb(reg, dev->port_index);
	ret = readb(dev->port_data);
	barrier();

	return ret;
}

static __inline__ void matrox_w1_write_reg(struct matrox_device *dev, u8 reg, u8 val)
{
	writeb(reg, dev->port_index);
	writeb(val, dev->port_data);
	wmb();
}

static void matrox_w1_write_ddc_bit(unsigned long data, u8 bit)
{
	u8 ret;
	struct matrox_device *dev = (struct matrox_device *) data;

	if (bit)
		bit = 0;
	else
		bit = dev->data_mask;

	ret = matrox_w1_read_reg(dev, MATROX_GET_CONTROL);
	matrox_w1_write_reg(dev, MATROX_GET_CONTROL, ((ret & ~dev->data_mask) | bit));
	matrox_w1_write_reg(dev, MATROX_GET_DATA, 0x00);
}

static u8 matrox_w1_read_ddc_bit(unsigned long data)
{
	u8 ret;
	struct matrox_device *dev = (struct matrox_device *) data;

	ret = matrox_w1_read_reg(dev, MATROX_GET_DATA);

	return ret;
}

static void matrox_w1_hw_init(struct matrox_device *dev)
{
	matrox_w1_write_reg(dev, MATROX_GET_DATA, 0xFF);
	matrox_w1_write_reg(dev, MATROX_GET_CONTROL, 0x00);
}

static int __devinit matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
	struct matrox_device *dev;
	int err;

	assert(pdev != NULL);
	assert(ent != NULL);

	if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400)
		return -ENODEV;

	dev = kmalloc(sizeof(struct matrox_device) +
		       sizeof(struct w1_bus_master), GFP_KERNEL);
	if (!dev) {
		dev_err(&pdev->dev,
			"%s: Failed to create new matrox_device object.\n",
			__func__);
		return -ENOMEM;
	}

	memset(dev, 0, sizeof(struct matrox_device) + sizeof(struct w1_bus_master));

	dev->bus_master = (struct w1_bus_master *)(dev + 1);

	/* 
	 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c 
	 */

	dev->phys_addr = pci_resource_start(pdev, 1);

	dev->virt_addr = ioremap_nocache(dev->phys_addr, 16384);
	if (!dev->virt_addr) {
		dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n",
			__func__, dev->phys_addr, 16384);
		err = -EIO;
		goto err_out_free_device;
	}

	dev->base_addr = dev->virt_addr + MATROX_BASE;
	dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET;
	dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET;
	dev->data_mask = (MATROX_G400_DDC_DATA);

	matrox_w1_hw_init(dev);

	dev->bus_master->data = (unsigned long) dev;
	dev->bus_master->read_bit = &matrox_w1_read_ddc_bit;
	dev->bus_master->write_bit = &matrox_w1_write_ddc_bit;

	err = w1_add_master_device(dev->bus_master);
	if (err)
		goto err_out_free_device;

	pci_set_drvdata(pdev, dev);

	dev->found = 1;

	dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n");

	return 0;

err_out_free_device:
	kfree(dev);

	return err;
}

static void __devexit matrox_w1_remove(struct pci_dev *pdev)
{
	struct matrox_device *dev = pci_get_drvdata(pdev);

	assert(dev != NULL);

	if (dev->found) {
		w1_remove_master_device(dev->bus_master);
		iounmap(dev->virt_addr);
	}
	kfree(dev);
}

static int __init matrox_w1_init(void)
{
	return pci_register_driver(&matrox_w1_pci_driver);
}

static void __exit matrox_w1_fini(void)
{
	pci_unregister_driver(&matrox_w1_pci_driver);
}

module_init(matrox_w1_init);
module_exit(matrox_w1_fini);