1 /*
2 * Copyright (C) 2005-2006 Micronas USA Inc.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License (Version 2) as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software Foundation,
15 * Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
16 */
17
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/delay.h>
21 #include <linux/sched.h>
22 #include <linux/list.h>
23 #include <linux/unistd.h>
24 #include <linux/time.h>
25 #include <linux/device.h>
26 #include <linux/i2c.h>
27 #include <linux/mutex.h>
28 #include <linux/uaccess.h>
29 #include <asm/system.h>
30
31 #include "go7007-priv.h"
32 #include "wis-i2c.h"
33
34 /********************* Driver for on-board I2C adapter *********************/
35
36 /* #define GO7007_I2C_DEBUG */
37
38 #define SPI_I2C_ADDR_BASE 0x1400
39 #define STATUS_REG_ADDR (SPI_I2C_ADDR_BASE + 0x2)
40 #define I2C_CTRL_REG_ADDR (SPI_I2C_ADDR_BASE + 0x6)
41 #define I2C_DEV_UP_ADDR_REG_ADDR (SPI_I2C_ADDR_BASE + 0x7)
42 #define I2C_LO_ADDR_REG_ADDR (SPI_I2C_ADDR_BASE + 0x8)
43 #define I2C_DATA_REG_ADDR (SPI_I2C_ADDR_BASE + 0x9)
44 #define I2C_CLKFREQ_REG_ADDR (SPI_I2C_ADDR_BASE + 0xa)
45
46 #define I2C_STATE_MASK 0x0007
47 #define I2C_READ_READY_MASK 0x0008
48
49 /* There is only one I2C port on the TW2804 that feeds all four GO7007 VIPs
50 * on the Adlink PCI-MPG24, so access is shared between all of them. */
51 static DEFINE_MUTEX(adlink_mpg24_i2c_lock);
52
go7007_i2c_xfer(struct go7007 * go,u16 addr,int read,u16 command,int flags,u8 * data)53 static int go7007_i2c_xfer(struct go7007 *go, u16 addr, int read,
54 u16 command, int flags, u8 *data)
55 {
56 int i, ret = -1;
57 u16 val;
58
59 if (go->status == STATUS_SHUTDOWN)
60 return -1;
61
62 #ifdef GO7007_I2C_DEBUG
63 if (read)
64 printk(KERN_DEBUG "go7007-i2c: reading 0x%02x on 0x%02x\n",
65 command, addr);
66 else
67 printk(KERN_DEBUG
68 "go7007-i2c: writing 0x%02x to 0x%02x on 0x%02x\n",
69 *data, command, addr);
70 #endif
71
72 mutex_lock(&go->hw_lock);
73
74 if (go->board_id == GO7007_BOARDID_ADLINK_MPG24) {
75 /* Bridge the I2C port on this GO7007 to the shared bus */
76 mutex_lock(&adlink_mpg24_i2c_lock);
77 go7007_write_addr(go, 0x3c82, 0x0020);
78 }
79
80 /* Wait for I2C adapter to be ready */
81 for (i = 0; i < 10; ++i) {
82 if (go7007_read_addr(go, STATUS_REG_ADDR, &val) < 0)
83 goto i2c_done;
84 if (!(val & I2C_STATE_MASK))
85 break;
86 msleep(100);
87 }
88 if (i == 10) {
89 printk(KERN_ERR "go7007-i2c: I2C adapter is hung\n");
90 goto i2c_done;
91 }
92
93 /* Set target register (command) */
94 go7007_write_addr(go, I2C_CTRL_REG_ADDR, flags);
95 go7007_write_addr(go, I2C_LO_ADDR_REG_ADDR, command);
96
97 /* If we're writing, send the data and target address and we're done */
98 if (!read) {
99 go7007_write_addr(go, I2C_DATA_REG_ADDR, *data);
100 go7007_write_addr(go, I2C_DEV_UP_ADDR_REG_ADDR,
101 (addr << 9) | (command >> 8));
102 ret = 0;
103 goto i2c_done;
104 }
105
106 /* Otherwise, we're reading. First clear i2c_rx_data_rdy. */
107 if (go7007_read_addr(go, I2C_DATA_REG_ADDR, &val) < 0)
108 goto i2c_done;
109
110 /* Send the target address plus read flag */
111 go7007_write_addr(go, I2C_DEV_UP_ADDR_REG_ADDR,
112 (addr << 9) | 0x0100 | (command >> 8));
113
114 /* Wait for i2c_rx_data_rdy */
115 for (i = 0; i < 10; ++i) {
116 if (go7007_read_addr(go, STATUS_REG_ADDR, &val) < 0)
117 goto i2c_done;
118 if (val & I2C_READ_READY_MASK)
119 break;
120 msleep(100);
121 }
122 if (i == 10) {
123 printk(KERN_ERR "go7007-i2c: I2C adapter is hung\n");
124 goto i2c_done;
125 }
126
127 /* Retrieve the read byte */
128 if (go7007_read_addr(go, I2C_DATA_REG_ADDR, &val) < 0)
129 goto i2c_done;
130 *data = val;
131 ret = 0;
132
133 i2c_done:
134 if (go->board_id == GO7007_BOARDID_ADLINK_MPG24) {
135 /* Isolate the I2C port on this GO7007 from the shared bus */
136 go7007_write_addr(go, 0x3c82, 0x0000);
137 mutex_unlock(&adlink_mpg24_i2c_lock);
138 }
139 mutex_unlock(&go->hw_lock);
140 return ret;
141 }
142
go7007_smbus_xfer(struct i2c_adapter * adapter,u16 addr,unsigned short flags,char read_write,u8 command,int size,union i2c_smbus_data * data)143 static int go7007_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
144 unsigned short flags, char read_write,
145 u8 command, int size, union i2c_smbus_data *data)
146 {
147 struct go7007 *go = i2c_get_adapdata(adapter);
148
149 if (size != I2C_SMBUS_BYTE_DATA)
150 return -1;
151 return go7007_i2c_xfer(go, addr, read_write == I2C_SMBUS_READ, command,
152 flags & I2C_CLIENT_SCCB ? 0x10 : 0x00, &data->byte);
153 }
154
155 /* VERY LIMITED I2C master xfer function -- only needed because the
156 * SMBus functions only support 8-bit commands and the SAA7135 uses
157 * 16-bit commands. The I2C interface on the GO7007, as limited as
158 * it is, does support this mode. */
159
go7007_i2c_master_xfer(struct i2c_adapter * adapter,struct i2c_msg msgs[],int num)160 static int go7007_i2c_master_xfer(struct i2c_adapter *adapter,
161 struct i2c_msg msgs[], int num)
162 {
163 struct go7007 *go = i2c_get_adapdata(adapter);
164 int i;
165
166 for (i = 0; i < num; ++i) {
167 /* We can only do two things here -- write three bytes, or
168 * write two bytes and read one byte. */
169 if (msgs[i].len == 2) {
170 if (i + 1 == num || msgs[i].addr != msgs[i + 1].addr ||
171 (msgs[i].flags & I2C_M_RD) ||
172 !(msgs[i + 1].flags & I2C_M_RD) ||
173 msgs[i + 1].len != 1)
174 return -1;
175 if (go7007_i2c_xfer(go, msgs[i].addr, 1,
176 (msgs[i].buf[0] << 8) | msgs[i].buf[1],
177 0x01, &msgs[i + 1].buf[0]) < 0)
178 return -1;
179 ++i;
180 } else if (msgs[i].len == 3) {
181 if (msgs[i].flags & I2C_M_RD)
182 return -1;
183 if (msgs[i].len != 3)
184 return -1;
185 if (go7007_i2c_xfer(go, msgs[i].addr, 0,
186 (msgs[i].buf[0] << 8) | msgs[i].buf[1],
187 0x01, &msgs[i].buf[2]) < 0)
188 return -1;
189 } else
190 return -1;
191 }
192
193 return 0;
194 }
195
go7007_functionality(struct i2c_adapter * adapter)196 static u32 go7007_functionality(struct i2c_adapter *adapter)
197 {
198 return I2C_FUNC_SMBUS_BYTE_DATA;
199 }
200
201 static struct i2c_algorithm go7007_algo = {
202 .smbus_xfer = go7007_smbus_xfer,
203 .master_xfer = go7007_i2c_master_xfer,
204 .functionality = go7007_functionality,
205 };
206
207 static struct i2c_adapter go7007_adap_templ = {
208 .owner = THIS_MODULE,
209 .name = "WIS GO7007SB",
210 .algo = &go7007_algo,
211 };
212
go7007_i2c_init(struct go7007 * go)213 int go7007_i2c_init(struct go7007 *go)
214 {
215 memcpy(&go->i2c_adapter, &go7007_adap_templ,
216 sizeof(go7007_adap_templ));
217 go->i2c_adapter.dev.parent = go->dev;
218 i2c_set_adapdata(&go->i2c_adapter, go);
219 if (i2c_add_adapter(&go->i2c_adapter) < 0) {
220 printk(KERN_ERR
221 "go7007-i2c: error: i2c_add_adapter failed\n");
222 return -1;
223 }
224 return 0;
225 }
226