tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright 1998-2009 VIA Technologies, Inc. All Rights Reserved.
3 * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
4
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public
7 * License as published by the Free Software Foundation;
8 * either version 2, or (at your option) any later version.
9
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
12 * the implied warranty of MERCHANTABILITY or FITNESS FOR
13 * A PARTICULAR PURPOSE.See the GNU General Public License
14 * for more details.
15
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc.,
19 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 */
21
22#include <linux/platform_device.h>
23#include <linux/delay.h>
24#include <linux/spinlock.h>
25#include <linux/module.h>
26#include <linux/via-core.h>
27#include <linux/via_i2c.h>
28
29/*
30 * There can only be one set of these, so there's no point in having
31 * them be dynamically allocated...
32 */
33#define VIAFB_NUM_I2C 5
34static struct via_i2c_stuff via_i2c_par[VIAFB_NUM_I2C];
35static struct viafb_dev *i2c_vdev; /* Passed in from core */
36
37static void via_i2c_setscl(void *data, int state)
38{
39 u8 val;
40 struct via_port_cfg *adap_data = data;
41 unsigned long flags;
42
43 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
44 val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;
45 if (state)
46 val |= 0x20;
47 else
48 val &= ~0x20;
49 switch (adap_data->type) {
50 case VIA_PORT_I2C:
51 val |= 0x01;
52 break;
53 case VIA_PORT_GPIO:
54 val |= 0x80;
55 break;
56 default:
57 printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");
58 }
59 via_write_reg(adap_data->io_port, adap_data->ioport_index, val);
60 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
61}
62
63static int via_i2c_getscl(void *data)
64{
65 struct via_port_cfg *adap_data = data;
66 unsigned long flags;
67 int ret = 0;
68
69 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
70 if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x08)
71 ret = 1;
72 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
73 return ret;
74}
75
76static int via_i2c_getsda(void *data)
77{
78 struct via_port_cfg *adap_data = data;
79 unsigned long flags;
80 int ret = 0;
81
82 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
83 if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x04)
84 ret = 1;
85 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
86 return ret;
87}
88
89static void via_i2c_setsda(void *data, int state)
90{
91 u8 val;
92 struct via_port_cfg *adap_data = data;
93 unsigned long flags;
94
95 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
96 val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;
97 if (state)
98 val |= 0x10;
99 else
100 val &= ~0x10;
101 switch (adap_data->type) {
102 case VIA_PORT_I2C:
103 val |= 0x01;
104 break;
105 case VIA_PORT_GPIO:
106 val |= 0x40;
107 break;
108 default:
109 printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");
110 }
111 via_write_reg(adap_data->io_port, adap_data->ioport_index, val);
112 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
113}
114
115int viafb_i2c_readbyte(u8 adap, u8 slave_addr, u8 index, u8 *pdata)
116{
117 int ret;
118 u8 mm1[] = {0x00};
119 struct i2c_msg msgs[2];
120
121 if (!via_i2c_par[adap].is_active)
122 return -ENODEV;
123 *pdata = 0;
124 msgs[0].flags = 0;
125 msgs[1].flags = I2C_M_RD;
126 msgs[0].addr = msgs[1].addr = slave_addr / 2;
127 mm1[0] = index;
128 msgs[0].len = 1; msgs[1].len = 1;
129 msgs[0].buf = mm1; msgs[1].buf = pdata;
130 ret = i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);
131 if (ret == 2)
132 ret = 0;
133 else if (ret >= 0)
134 ret = -EIO;
135
136 return ret;
137}
138
139int viafb_i2c_writebyte(u8 adap, u8 slave_addr, u8 index, u8 data)
140{
141 int ret;
142 u8 msg[2] = { index, data };
143 struct i2c_msg msgs;
144
145 if (!via_i2c_par[adap].is_active)
146 return -ENODEV;
147 msgs.flags = 0;
148 msgs.addr = slave_addr / 2;
149 msgs.len = 2;
150 msgs.buf = msg;
151 ret = i2c_transfer(&via_i2c_par[adap].adapter, &msgs, 1);
152 if (ret == 1)
153 ret = 0;
154 else if (ret >= 0)
155 ret = -EIO;
156
157 return ret;
158}
159
160int viafb_i2c_readbytes(u8 adap, u8 slave_addr, u8 index, u8 *buff, int buff_len)
161{
162 int ret;
163 u8 mm1[] = {0x00};
164 struct i2c_msg msgs[2];
165
166 if (!via_i2c_par[adap].is_active)
167 return -ENODEV;
168 msgs[0].flags = 0;
169 msgs[1].flags = I2C_M_RD;
170 msgs[0].addr = msgs[1].addr = slave_addr / 2;
171 mm1[0] = index;
172 msgs[0].len = 1; msgs[1].len = buff_len;
173 msgs[0].buf = mm1; msgs[1].buf = buff;
174 ret = i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);
175 if (ret == 2)
176 ret = 0;
177 else if (ret >= 0)
178 ret = -EIO;
179
180 return ret;
181}
182
183/*
184 * Allow other viafb subdevices to look up a specific adapter
185 * by port name.
186 */
187struct i2c_adapter *viafb_find_i2c_adapter(enum viafb_i2c_adap which)
188{
189 struct via_i2c_stuff *stuff = &via_i2c_par[which];
190
191 return &stuff->adapter;
192}
193EXPORT_SYMBOL_GPL(viafb_find_i2c_adapter);
194
195
196static int create_i2c_bus(struct i2c_adapter *adapter,
197 struct i2c_algo_bit_data *algo,
198 struct via_port_cfg *adap_cfg,
199 struct pci_dev *pdev)
200{
201 algo->setsda = via_i2c_setsda;
202 algo->setscl = via_i2c_setscl;
203 algo->getsda = via_i2c_getsda;
204 algo->getscl = via_i2c_getscl;
205 algo->udelay = 10;
206 algo->timeout = 2;
207 algo->data = adap_cfg;
208
209 sprintf(adapter->name, "viafb i2c io_port idx 0x%02x",
210 adap_cfg->ioport_index);
211 adapter->owner = THIS_MODULE;
212 adapter->class = I2C_CLASS_DDC;
213 adapter->algo_data = algo;
214 if (pdev)
215 adapter->dev.parent = &pdev->dev;
216 else
217 adapter->dev.parent = NULL;
218 /* i2c_set_adapdata(adapter, adap_cfg); */
219
220 /* Raise SCL and SDA */
221 via_i2c_setsda(adap_cfg, 1);
222 via_i2c_setscl(adap_cfg, 1);
223 udelay(20);
224
225 return i2c_bit_add_bus(adapter);
226}
227
228static int viafb_i2c_probe(struct platform_device *platdev)
229{
230 int i, ret;
231 struct via_port_cfg *configs;
232
233 i2c_vdev = platdev->dev.platform_data;
234 configs = i2c_vdev->port_cfg;
235
236 for (i = 0; i < VIAFB_NUM_PORTS; i++) {
237 struct via_port_cfg *adap_cfg = configs++;
238 struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];
239
240 i2c_stuff->is_active = 0;
241 if (adap_cfg->type == 0 || adap_cfg->mode != VIA_MODE_I2C)
242 continue;
243 ret = create_i2c_bus(&i2c_stuff->adapter,
244 &i2c_stuff->algo, adap_cfg,
245 NULL); /* FIXME: PCIDEV */
246 if (ret < 0) {
247 printk(KERN_ERR "viafb: cannot create i2c bus %u:%d\n",
248 i, ret);
249 continue; /* Still try to make the rest */
250 }
251 i2c_stuff->is_active = 1;
252 }
253
254 return 0;
255}
256
257static int viafb_i2c_remove(struct platform_device *platdev)
258{
259 int i;
260
261 for (i = 0; i < VIAFB_NUM_PORTS; i++) {
262 struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];
263 /*
264 * Only remove those entries in the array that we've
265 * actually used (and thus initialized algo_data)
266 */
267 if (i2c_stuff->is_active)
268 i2c_del_adapter(&i2c_stuff->adapter);
269 }
270 return 0;
271}
272
273static struct platform_driver via_i2c_driver = {
274 .driver = {
275 .name = "viafb-i2c",
276 },
277 .probe = viafb_i2c_probe,
278 .remove = viafb_i2c_remove,
279};
280
281int viafb_i2c_init(void)
282{
283 return platform_driver_register(&via_i2c_driver);
284}
285
286void viafb_i2c_exit(void)
287{
288 platform_driver_unregister(&via_i2c_driver);
289}