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. */ 51static DEFINE_MUTEX(adlink_mpg24_i2c_lock); 52 53static 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 133i2c_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 143static 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 160static 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 196static u32 go7007_functionality(struct i2c_adapter *adapter) 197{ 198 return I2C_FUNC_SMBUS_BYTE_DATA; 199} 200 201static struct i2c_algorithm go7007_algo = { 202 .smbus_xfer = go7007_smbus_xfer, 203 .master_xfer = go7007_i2c_master_xfer, 204 .functionality = go7007_functionality, 205}; 206 207static struct i2c_adapter go7007_adap_templ = { 208 .owner = THIS_MODULE, 209 .name = "WIS GO7007SB", 210 .algo = &go7007_algo, 211}; 212 213int 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