1 /* 2 * Hardware monitoring driver for ZL6100 and compatibles 3 * 4 * Copyright (c) 2011 Ericsson AB. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License 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., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/err.h> 25 #include <linux/slab.h> 26 #include <linux/i2c.h> 27 #include <linux/ktime.h> 28 #include <linux/delay.h> 29 #include "pmbus.h" 30 31 enum chips { zl2004, zl2005, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105, 32 zl9101, zl9117 }; 33 34 struct zl6100_data { 35 int id; 36 ktime_t access; /* chip access time */ 37 int delay; /* Delay between chip accesses in uS */ 38 struct pmbus_driver_info info; 39 }; 40 41 #define to_zl6100_data(x) container_of(x, struct zl6100_data, info) 42 43 #define ZL6100_MFR_CONFIG 0xd0 44 #define ZL6100_DEVICE_ID 0xe4 45 46 #define ZL6100_MFR_XTEMP_ENABLE (1 << 7) 47 48 #define ZL6100_WAIT_TIME 1000 /* uS */ 49 50 static ushort delay = ZL6100_WAIT_TIME; 51 module_param(delay, ushort, 0644); 52 MODULE_PARM_DESC(delay, "Delay between chip accesses in uS"); 53 54 /* Some chips need a delay between accesses */ 55 static inline void zl6100_wait(const struct zl6100_data *data) 56 { 57 if (data->delay) { 58 s64 delta = ktime_us_delta(ktime_get(), data->access); 59 if (delta < data->delay) 60 udelay(data->delay - delta); 61 } 62 } 63 64 static int zl6100_read_word_data(struct i2c_client *client, int page, int reg) 65 { 66 const struct pmbus_driver_info *info = pmbus_get_driver_info(client); 67 struct zl6100_data *data = to_zl6100_data(info); 68 int ret; 69 70 if (page || reg >= PMBUS_VIRT_BASE) 71 return -ENXIO; 72 73 if (data->id == zl2005) { 74 /* 75 * Limit register detection is not reliable on ZL2005. 76 * Make sure registers are not erroneously detected. 77 */ 78 switch (reg) { 79 case PMBUS_VOUT_OV_WARN_LIMIT: 80 case PMBUS_VOUT_UV_WARN_LIMIT: 81 case PMBUS_IOUT_OC_WARN_LIMIT: 82 return -ENXIO; 83 } 84 } 85 86 zl6100_wait(data); 87 ret = pmbus_read_word_data(client, page, reg); 88 data->access = ktime_get(); 89 90 return ret; 91 } 92 93 static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg) 94 { 95 const struct pmbus_driver_info *info = pmbus_get_driver_info(client); 96 struct zl6100_data *data = to_zl6100_data(info); 97 int ret; 98 99 if (page > 0) 100 return -ENXIO; 101 102 zl6100_wait(data); 103 ret = pmbus_read_byte_data(client, page, reg); 104 data->access = ktime_get(); 105 106 return ret; 107 } 108 109 static int zl6100_write_word_data(struct i2c_client *client, int page, int reg, 110 u16 word) 111 { 112 const struct pmbus_driver_info *info = pmbus_get_driver_info(client); 113 struct zl6100_data *data = to_zl6100_data(info); 114 int ret; 115 116 if (page || reg >= PMBUS_VIRT_BASE) 117 return -ENXIO; 118 119 zl6100_wait(data); 120 ret = pmbus_write_word_data(client, page, reg, word); 121 data->access = ktime_get(); 122 123 return ret; 124 } 125 126 static int zl6100_write_byte(struct i2c_client *client, int page, u8 value) 127 { 128 const struct pmbus_driver_info *info = pmbus_get_driver_info(client); 129 struct zl6100_data *data = to_zl6100_data(info); 130 int ret; 131 132 if (page > 0) 133 return -ENXIO; 134 135 zl6100_wait(data); 136 ret = pmbus_write_byte(client, page, value); 137 data->access = ktime_get(); 138 139 return ret; 140 } 141 142 static const struct i2c_device_id zl6100_id[] = { 143 {"bmr450", zl2005}, 144 {"bmr451", zl2005}, 145 {"bmr462", zl2008}, 146 {"bmr463", zl2008}, 147 {"bmr464", zl2008}, 148 {"zl2004", zl2004}, 149 {"zl2005", zl2005}, 150 {"zl2006", zl2006}, 151 {"zl2008", zl2008}, 152 {"zl2105", zl2105}, 153 {"zl2106", zl2106}, 154 {"zl6100", zl6100}, 155 {"zl6105", zl6105}, 156 {"zl9101", zl9101}, 157 {"zl9117", zl9117}, 158 { } 159 }; 160 MODULE_DEVICE_TABLE(i2c, zl6100_id); 161 162 static int zl6100_probe(struct i2c_client *client, 163 const struct i2c_device_id *id) 164 { 165 int ret; 166 struct zl6100_data *data; 167 struct pmbus_driver_info *info; 168 u8 device_id[I2C_SMBUS_BLOCK_MAX + 1]; 169 const struct i2c_device_id *mid; 170 171 if (!i2c_check_functionality(client->adapter, 172 I2C_FUNC_SMBUS_READ_WORD_DATA 173 | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) 174 return -ENODEV; 175 176 ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID, 177 device_id); 178 if (ret < 0) { 179 dev_err(&client->dev, "Failed to read device ID\n"); 180 return ret; 181 } 182 device_id[ret] = '\0'; 183 dev_info(&client->dev, "Device ID %s\n", device_id); 184 185 mid = NULL; 186 for (mid = zl6100_id; mid->name[0]; mid++) { 187 if (!strncasecmp(mid->name, device_id, strlen(mid->name))) 188 break; 189 } 190 if (!mid->name[0]) { 191 dev_err(&client->dev, "Unsupported device\n"); 192 return -ENODEV; 193 } 194 if (id->driver_data != mid->driver_data) 195 dev_notice(&client->dev, 196 "Device mismatch: Configured %s, detected %s\n", 197 id->name, mid->name); 198 199 data = devm_kzalloc(&client->dev, sizeof(struct zl6100_data), 200 GFP_KERNEL); 201 if (!data) 202 return -ENOMEM; 203 204 data->id = mid->driver_data; 205 206 /* 207 * According to information from the chip vendor, all currently 208 * supported chips are known to require a wait time between I2C 209 * accesses. 210 */ 211 data->delay = delay; 212 213 /* 214 * Since there was a direct I2C device access above, wait before 215 * accessing the chip again. 216 */ 217 data->access = ktime_get(); 218 zl6100_wait(data); 219 220 info = &data->info; 221 222 info->pages = 1; 223 info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT 224 | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT 225 | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT 226 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP; 227 228 ret = i2c_smbus_read_word_data(client, ZL6100_MFR_CONFIG); 229 if (ret < 0) 230 return ret; 231 232 if (ret & ZL6100_MFR_XTEMP_ENABLE) 233 info->func[0] |= PMBUS_HAVE_TEMP2; 234 235 data->access = ktime_get(); 236 zl6100_wait(data); 237 238 info->read_word_data = zl6100_read_word_data; 239 info->read_byte_data = zl6100_read_byte_data; 240 info->write_word_data = zl6100_write_word_data; 241 info->write_byte = zl6100_write_byte; 242 243 return pmbus_do_probe(client, mid, info); 244 } 245 246 static struct i2c_driver zl6100_driver = { 247 .driver = { 248 .name = "zl6100", 249 }, 250 .probe = zl6100_probe, 251 .remove = pmbus_do_remove, 252 .id_table = zl6100_id, 253 }; 254 255 module_i2c_driver(zl6100_driver); 256 257 MODULE_AUTHOR("Guenter Roeck"); 258 MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles"); 259 MODULE_LICENSE("GPL"); 260