aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/video/via/via_i2c.c
blob: 2291765f2f8efe06929d4799e6b50c7fa8bd3637 (plain) (blame)
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
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
/*
 * Copyright 1998-2009 VIA Technologies, Inc. All Rights Reserved.
 * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.

 * 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, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; 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 <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include "via-core.h"
#include "via_i2c.h"

/*
 * There can only be one set of these, so there's no point in having
 * them be dynamically allocated...
 */
#define VIAFB_NUM_I2C		5
static struct via_i2c_stuff via_i2c_par[VIAFB_NUM_I2C];
struct viafb_dev *i2c_vdev;  /* Passed in from core */

static void via_i2c_setscl(void *data, int state)
{
	u8 val;
	struct via_port_cfg *adap_data = data;
	unsigned long flags;

	spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
	val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;
	if (state)
		val |= 0x20;
	else
		val &= ~0x20;
	switch (adap_data->type) {
	case VIA_PORT_I2C:
		val |= 0x01;
		break;
	case VIA_PORT_GPIO:
		val |= 0x80;
		break;
	default:
		printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");
	}
	via_write_reg(adap_data->io_port, adap_data->ioport_index, val);
	spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
}

static int via_i2c_getscl(void *data)
{
	struct via_port_cfg *adap_data = data;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
	if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x08)
		ret = 1;
	spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
	return ret;
}

static int via_i2c_getsda(void *data)
{
	struct via_port_cfg *adap_data = data;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
	if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x04)
		ret = 1;
	spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
	return ret;
}

static void via_i2c_setsda(void *data, int state)
{
	u8 val;
	struct via_port_cfg *adap_data = data;
	unsigned long flags;

	spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
	val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;
	if (state)
		val |= 0x10;
	else
		val &= ~0x10;
	switch (adap_data->type) {
	case VIA_PORT_I2C:
		val |= 0x01;
		break;
	case VIA_PORT_GPIO:
		val |= 0x40;
		break;
	default:
		printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");
	}
	via_write_reg(adap_data->io_port, adap_data->ioport_index, val);
	spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
}

int viafb_i2c_readbyte(u8 adap, u8 slave_addr, u8 index, u8 *pdata)
{
	u8 mm1[] = {0x00};
	struct i2c_msg msgs[2];

	if (!via_i2c_par[adap].is_active)
		return -ENODEV;
	*pdata = 0;
	msgs[0].flags = 0;
	msgs[1].flags = I2C_M_RD;
	msgs[0].addr = msgs[1].addr = slave_addr / 2;
	mm1[0] = index;
	msgs[0].len = 1; msgs[1].len = 1;
	msgs[0].buf = mm1; msgs[1].buf = pdata;
	return i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);
}

int viafb_i2c_writebyte(u8 adap, u8 slave_addr, u8 index, u8 data)
{
	u8 msg[2] = { index, data };
	struct i2c_msg msgs;

	if (!via_i2c_par[adap].is_active)
		return -ENODEV;
	msgs.flags = 0;
	msgs.addr = slave_addr / 2;
	msgs.len = 2;
	msgs.buf = msg;
	return i2c_transfer(&via_i2c_par[adap].adapter, &msgs, 1);
}

int viafb_i2c_readbytes(u8 adap, u8 slave_addr, u8 index, u8 *buff, int buff_len)
{
	u8 mm1[] = {0x00};
	struct i2c_msg msgs[2];

	if (!via_i2c_par[adap].is_active)
		return -ENODEV;
	msgs[0].flags = 0;
	msgs[1].flags = I2C_M_RD;
	msgs[0].addr = msgs[1].addr = slave_addr / 2;
	mm1[0] = index;
	msgs[0].len = 1; msgs[1].len = buff_len;
	msgs[0].buf = mm1; msgs[1].buf = buff;
	return i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);
}

/*
 * Allow other viafb subdevices to look up a specific adapter
 * by port name.
 */
struct i2c_adapter *viafb_find_i2c_adapter(enum viafb_i2c_adap which)
{
	struct via_i2c_stuff *stuff = &via_i2c_par[which];

	return &stuff->adapter;
}
EXPORT_SYMBOL_GPL(viafb_find_i2c_adapter);


static int create_i2c_bus(struct i2c_adapter *adapter,
			  struct i2c_algo_bit_data *algo,
			  struct via_port_cfg *adap_cfg,
			  struct pci_dev *pdev)
{
	algo->setsda = via_i2c_setsda;
	algo->setscl = via_i2c_setscl;
	algo->getsda = via_i2c_getsda;
	algo->getscl = via_i2c_getscl;
	algo->udelay = 40;
	algo->timeout = 20;
	algo->data = adap_cfg;

	sprintf(adapter->name, "viafb i2c io_port idx 0x%02x",
		adap_cfg->ioport_index);
	adapter->owner = THIS_MODULE;
	adapter->id = 0x01FFFF;
	adapter->class = I2C_CLASS_DDC;
	adapter->algo_data = algo;
	if (pdev)
		adapter->dev.parent = &pdev->dev;
	else
		adapter->dev.parent = NULL;
	/* i2c_set_adapdata(adapter, adap_cfg); */

	/* Raise SCL and SDA */
	via_i2c_setsda(adap_cfg, 1);
	via_i2c_setscl(adap_cfg, 1);
	udelay(20);

	return i2c_bit_add_bus(adapter);
}

static int viafb_i2c_probe(struct platform_device *platdev)
{
	int i, ret;
	struct via_port_cfg *configs;

	i2c_vdev = platdev->dev.platform_data;
	configs = i2c_vdev->port_cfg;

	for (i = 0; i < VIAFB_NUM_PORTS; i++) {
		struct via_port_cfg *adap_cfg = configs++;
		struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];

		i2c_stuff->is_active = 0;
		if (adap_cfg->type == 0 || adap_cfg->mode != VIA_MODE_I2C)
			continue;
		ret = create_i2c_bus(&i2c_stuff->adapter,
				     &i2c_stuff->algo, adap_cfg,
				NULL); /* FIXME: PCIDEV */
		if (ret < 0) {
			printk(KERN_ERR "viafb: cannot create i2c bus %u:%d\n",
				i, ret);
			continue;  /* Still try to make the rest */
		}
		i2c_stuff->is_active = 1;
	}

	return 0;
}

static int viafb_i2c_remove(struct platform_device *platdev)
{
	int i;

	for (i = 0; i < VIAFB_NUM_PORTS; i++) {
		struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];
		/*
		 * Only remove those entries in the array that we've
		 * actually used (and thus initialized algo_data)
		 */
		if (i2c_stuff->is_active)
			i2c_del_adapter(&i2c_stuff->adapter);
	}
	return 0;
}

static struct platform_driver via_i2c_driver = {
	.driver = {
		.name = "viafb-i2c",
	},
	.probe = viafb_i2c_probe,
	.remove = viafb_i2c_remove,
};

int viafb_i2c_init(void)
{
	return platform_driver_register(&via_i2c_driver);
}

void viafb_i2c_exit(void)
{
	platform_driver_unregister(&via_i2c_driver);
}